Science.gov

Sample records for developing attractive magnetic

  1. Magnetic bearings grow more attractive

    SciTech Connect

    Not Available

    1993-10-01

    Advances in materials and electronics have enabled designers to devise simpler, smaller magnetic bearings. As a result, costs have dropped, widening the applications for these very-low-friction devices. Avcon (Advanced Controls Technology) has patented a permanent-magnet bias actively controlled bearing. Here high-energy rare earth permanent-magnet materials supply the basic bearing load levitation, while servo-driven electromagnets generate stabilization and centering forces for motion contol. Previous heavy-duty magnetic bearings used electromagnets entirely for suspension and control, which led to large bearings and control systems with higher power requirements. Avcon has developed several types of permanent-magnet bias bearings. The simplest is the radial repulsion bearing. Avcon's homopolar permanent-magnet bias active bearing is the most versatile of the company's designs.

  2. Physical attractiveness and personality development.

    PubMed

    Shea, J; Crossman, S M; Adams, G R

    1978-05-01

    A test of the relationship between physical attractiveness and ego development was completed through an interview study of 294 men and women college students. Ss responded to personality measures assessing identity formation, locus of control, and ego functioning and were rated on facial attractiveness and body form scales. Contrary to the physical attractiveness stereotype, attractive and unattractive Ss did not differ in their personality styles. PMID:650605

  3. Nonlinear dynamics of attractive magnetic bearings

    NASA Technical Reports Server (NTRS)

    Hebbale, K. V.; Taylor, D. L.

    1987-01-01

    The nonlinear dynamics of a ferromagnetic shaft suspended by the force of attraction of 1, 2, or 4 independent electromagnets is presented. Each model includes a state variable feedback controller which has been designed using the pole placement method. The constitutive relationships for the magnets are derived analytically from magnetic circuit theory, and the effects of induced eddy currents due to the rotation of the journal are included using Maxwell's field relations. A rotor suspended by four electro-magnets with closed loop feedback is shown to have nine equilibrium points within the bearing clearance space. As the rotor spin speed increases, the system is shown to pass through a Hopf bifurcation (a flutter instability). Using center manifold theory, this bifurcation can be shown to be of the subcritical type, indicating an unstable limit cycle below the critical speed. The bearing is very sensitive to initial conditions, and the equilibrium position is easily upset by transient excitation. The results are confirmed by numerical simulation.

  4. Magnet Trade Books: Attracting and Repelling Concepts

    ERIC Educational Resources Information Center

    Barrow, Lloyd H.; Robinson, Richard D.

    2007-01-01

    A series of magnet trade books were analyzed against a validated list of magnet concepts (Barrow, 1990a) and their Flesch (1974) Readability was determined. These trade books were used to supplement a second grade unit on magnetism locally constructed from AIM's "Mostly Magnets" (1991). All trade books accurately described how like and unlike…

  5. Physical Attraction: The Mysteries of Magnetism

    SciTech Connect

    Stohr, Joachim

    2004-12-14

    Most people have intuitive associations with the word 'magnetism' based on everyday life: refrigerator magnets, the compass, north and south poles, or someone's 'magnetic personality'. Few people, however, realize how complicated the phenomenon really is, how much research still deals with the topic today, and how much it penetrates our modern industrialized world - from electricity, wireless communication at the speed of light to magnetic sensors in cars and data storage in computers. Stohr's lecture will provide a glimpse at the magic and science behind magnetism: its long history, scientific breakthroughs in its understanding, and its use in our modern society. In the process Stohr will show how research at SSRL/SLAC is addressing some of the forefront issues in magnetism research and technology today.

  6. Magnetic water treatment: A coming attraction?

    SciTech Connect

    Fryer, L.

    1995-10-01

    United Airlines and pharmaceutical company Eli Lilly and Company are among a number of users that are controlling scale and corrosion in cooling tower loops with magnetic water treatment, a controversial technology that has met with skepticism, disbelief, and claims of fraud. Experts and hundreds of published papers disagree on whether magnetic water treatment works, and if so, how. No scientific theory has proven how magnets can treat water, nor are there documented, reproducible laboratory test results. Field experience is mixed, with some installations working well and others failing. Despite the controversy and the lack of an adequately documented theoretical underpinning, the existence of large, apparently successful installations lends credence to the view that at least some magnetic water treatment systems are effective. The stakes are high. Most large HVAC systems are currently treated with chemicals. These chemicals generally work well, but they are costly, in many cases are environmentally damaging, and are subject to increasingly strict regulations. A reliable, low-cost, and more environmentally benign alternative that eliminates or sharply reduces the need for chemical treatment would have obvious benefits. Based on the review of the literature, discussions with users, vendors, and independent analysts, and tours of several apparently successful installations, E Source believes that this technology works in some cases and warrants further investigation. They caution prospective users to shop carefully and to select vendors with an established track record.

  7. Magnetism and Electricity Activity "Attracts" Student Interest

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2010-01-01

    Electricity and magnetism are intimately linked, this relationship forming the basis of the modern electric utility system and the generation of bulk electrical energy. There is rich literature from which to teach students the basics, but nothing drives the point home like having them learn from firsthand experience--and that is what this…

  8. The Magnetic Attraction of Honeybee Navigation.

    ERIC Educational Resources Information Center

    Ayres, David

    1991-01-01

    Discussed are the division of labor, defenses, genetics and evolution, communication, and navigation power of honeybees. The scientific and cross-curricular themes that can be offered using the economically important honeybee are described. Research that suggests that bees may be flying magnets is also discussed. (KR)

  9. Nano Goes Magnetic to Attract Big Business

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Glenn Research Center has combined state-of-the-art electrical designs with complex, computer-aided analyses to develop some of today s most advanced power systems, in space and on Earth. The center s Power and On-Board Propulsion Technology Division is the brain behind many of these power systems. For space, this division builds technologies that help power the International Space Station, the Hubble Space Telescope, and Earth-orbiting satellites. For Earth, it has woven advanced aerospace power concepts into commercial energy applications that include solar and nuclear power generation, battery and fuel cell energy storage, communications and telecommunications satellites, cryocoolers, hybrid and electric vehicles, and heating and air-conditioning systems.

  10. Attracting Capital: Magnets, Charters, and School Referendum Success

    ERIC Educational Resources Information Center

    Shober, Arnold F.

    2011-01-01

    Does school choice enhance the ability of school districts to raise revenue? School districts use charter and magnet schools to attract and retain students, but does choice improve the odds for school districts seeking increased taxing authority at the polls? If those parents who choose schools are attentive to district policies, then increasing…

  11. Hidden Attraction - The History and Mystery of Magnetism

    NASA Astrophysics Data System (ADS)

    Verschuur, Gerrit L.

    1996-04-01

    Long one of nature's most fascinating phenomena, magnetism was once the subject of many superstitions. Magnets were thought useful to thieves, effective as a love potion, and as a cure for gout or spasms. They could remove sorcery from women and put demons to flight and even reconcile married couples. It was said that a lodestone pickled in the salt of sucking fish had the power to attract gold. Today, these beliefs have been put aside, but magnetism is no less remarkable for our modern understanding of it. In Hidden Attraction , Gerrit L. Verschuur, a noted astronomer and National Book Award nominee for The Invisible Universe , traces the history of our fascination with magnetism, from the mystery and superstition that propelled the first alchemical experiments with lodestone, through the more tangible works of Faraday, Maxwell, Hertz and other great pioneers of magnetism (scientists responsible for the extraordinary advances in modern science and technology, including radio, the telephone, and computers, that characterize the twentieth century), to state-of-the-art theories that see magnetism as a basic force in the universe. Boasting many informative illustrations, this is an adventure of the mind, using the specific phenomenon of magnetism to show how we have moved from an era of superstitions to one in which the Theory of Everything looms on the horizon.

  12. Attraction, merger, reflection, and annihilation in magnetic droplet soliton scattering

    NASA Astrophysics Data System (ADS)

    Maiden, M. D.; Bookman, L. D.; Hoefer, M. A.

    2014-05-01

    The interaction behaviors of solitons are defining characteristics of these nonlinear, coherent structures. Due to recent experimental observations, thin ferromagnetic films offer a promising medium in which to study the scattering properties of two-dimensional magnetic droplet solitons, particle-like, precessing dipoles. Here, a rich set of two-droplet interaction behaviors are classified through micromagnetic simulations. Repulsive and attractive interaction dynamics are generically determined by the relative phase and speeds of the two droplets and can be classified into four types: (1) merger into a breather bound state, (2) counterpropagation trapped along the axis of symmetry, (3) reflection, and (4) violent droplet annihilation into spin wave radiation and a breather. Utilizing a nonlinear method of images, it is demonstrated that these dynamics describe repulsive/attractive scattering of a single droplet off of a magnetic boundary with pinned/free spin boundary conditions, respectively. These results explain the mechanism by which propagating and stationary droplets can be stabilized in a confined ferromagnet.

  13. Same-Sex Attraction and Successful Adolescent Development

    ERIC Educational Resources Information Center

    Busseri, Michael A.; Willoughby, Teena; Chalmers, Heather; Bogaert, Anthony R.

    2006-01-01

    This study investigated the relation of adolescent same-sex attraction to "successful development" (Baltes, P. B., "Am. Psychol." 32:366-380, 1997). Based on a survey of high-school adolescents, four groups were defined according to the nature of self-reported sexual attraction: exclusively heterosexual (EHA; n=3594); mostly heterosexual (MHA;…

  14. The Magnetic Dipole as an Attractive Fusion Reactor

    NASA Astrophysics Data System (ADS)

    Dawson, John M.

    1997-11-01

    Stability for low β plasma confined by closed B field lines is PV^γ = C_0, P = pressure, V = flux tube volume, γ is c_p/cv = 5/3. Kesner(J. Kesner, Innovative Confinement Concepts Workshop, Mar. 3-6, 1997) proposed a levitated current ring with the plasma stabilized by this condition as an alternate fusion reactor. Such a reactor has many attractive features; at radii large compared to the ring radius, V goes like r^4; the stability condition is Pr^20/3 = C_1. If nr^4 = C_2, then interchanges keep the density constant. The temperature can drop according to Tr^8/3 = C_3. If the chamber is ten times the ring radius, the density can drop from 10^14 near the ring to 10^10 at the edge and the temperature can drop from 50 keV near the ring to 100 eV at the edge. This plasma should present no problems for a divertor. Reacting plasma near the ring will heat it, upsetting the stability relation and cause convection to carry burnt plasma out; it will cool as it expands. At the same time the convection will bring in fresh fuel from the outside which will be compressed and heated to ignition. A super conducting ring design that can float in reacting D-He^3 for 16 hours exists(J.M. Dawson, FUSION, edited by Edward Teller, Vol. 1, Magnetic Confinement, Part, Ch. 16, Academic Press, 1981).

  15. On the analytical form of the Earth's magnetic attraction expressed as a function of time

    NASA Technical Reports Server (NTRS)

    Carlheim-Gyllenskold, V.

    1983-01-01

    An attempt is made to express the Earth's magnetic attraction in simple analytical form using observations during the 16th to 19th centuries. Observations of the magnetic inclination in the 16th and 17th centuries are discussed.

  16. Corrigendum: Like a Magnet: Catharsis Beliefs Attract Angry People to Violent Video Games.

    PubMed

    2016-07-01

    Bushman, B. J., & Whitaker, J. L. (2010). Like a magnet: Catharsis beliefs attract angry people to violent video games. Psychological Science, 21, 790-792. (Original DOI: 10.1177/0956797610369494). PMID:27207875

  17. A study on the changes in attractive force of magnetic attachments for overdenture

    PubMed Central

    Lee, Jong-Hyuk; Choi, Yu-Sung

    2016-01-01

    PURPOSE Although magnetic attachment is used frequently for overdenture, it is reported that attractive force can be decreased by abrasion and corrosion. The purpose of this study was to establish the clinical basis about considerations and long term prognosis of overdenture using magnetic attachments by investigating the change in attractive force of magnetic attachment applied to the patients. MATERIALS AND METHODS Among the patients treated with overdenture using magnetic attachments in Dankook University Dental Hospital, attractive force records of 61 magnetic attachments of 20 subjects who re-visited from July 2013 to June 2014 were analyzed. Dental magnet tester (Aichi Micro Intelligent Co., Aichi, Japan) was used for measurement. The magnetic attachments used in this study were Magfit IP-B Flat, Magfit DX400, Magfit DX600 and Magfit DX800 (Aichi Steel Co., Aichi, Japan) filled with Neodymium (NdFeB), a rare-earth magnet. RESULTS Reduction ratio of attractive force had no significant correlation with conditional variables to which attachments were applied, and was higher when the maintenance period was longer (P<.05, r=.361). Reduction ratio of attractive force was significantly higher in the subject group in which attachments were used over 9 years than within 9 years (P<.05). Furthermore, 16.39% of total magnetic attachments showed detachment of keeper or assembly. CONCLUSION Attractive force of magnetic attachment is maintained regardless of conditional variables and reduction ratio increased as the maintenance period became longer. Further study on adhesive material, attachment method and design improvement to prevent detachment of magnetic attachment is needed. PMID:26949482

  18. Reproductive strategy, sexual development and attraction to facial characteristics.

    PubMed

    Cornwell, R Elisabeth; Law Smith, Miriam J; Boothroyd, Lynda G; Moore, Fhionna R; Davis, Hasker P; Stirrat, Michael; Tiddeman, Bernard; Perrett, David I

    2006-12-29

    Sexual reproduction strategies vary both between and within species in the level of investment in offspring. Life-history theories suggest that the rate of sexual maturation is critically linked to reproductive strategy, with high investment being associated with few offspring and delayed maturation. For humans, age of puberty and age of first sex are two developmental milestones that have been associated with reproductive strategies. Stress during early development can retard or accelerate sexual maturation and reproduction. Early age of menarche is associated with absence of younger siblings, absence of a father figure during early life and increased weight. Father absence during early life is also associated with early marriage, pregnancy and divorce. Choice of partner characteristics is critical to successful implementation of sexual strategies. It has been suggested that sexually dimorphic traits (including those evident in the face) signal high-quality immune function and reproductive status. Masculinity in males has also been associated with low investment in mate and offspring. Thus, women's reproductive strategy should be matched to the probability of male investment, hence to male masculinity. Our review leads us to predict associations between the rate of sexual maturation and adult preferences for facial characteristics (enhanced sexual dimorphism and attractiveness). We find for men, engaging in sex at an early age is related to an increased preference for feminized female faces. Similarly, for women, the earlier the age of first sex the greater the preference for masculinity in opposite-sex faces. When we controlled sexual dimorphism in male faces, the speed of sexual development in women was not associated with differences in preference for male facial attractiveness. These developmental influences on partner choice were not mediated by self-rated attractiveness or parental relationships. We conclude that individuals assort in preferences based on

  19. Crossover from impurity to valence band in diluted magnetic semiconductors: Role of Coulomb attraction by acceptors

    SciTech Connect

    Popescu, Florentin; Sen, Cengiz; Dagotto, Elbio R; Moreo, Adriana

    2007-01-01

    The crossover between an impurity band (IB) and a valence band (VB) regime as a function of the magnetic impurity concentration in a model for diluted magnetic semiconductors (DMSs) is studied systematically by taking into consideration the Coulomb attraction between the carriers and the magnetic impurities. The density of states and the ferromagnetic transition temperature of a spin-fermion model applied to DMSs are evaluated using dynamical mean-field theory and Monte Carlo (MC) calculations. It is shown that the addition of a square-well-like attractive potential can generate an IB at small enough Mn doping x for values of the p-d exchange J that are not strong enough to generate one by themselves. We observe that the IB merges with the VB when x>=xc where xc is a function of J and the Coulomb strength V. Using MC simulations, we demonstrate that the range of the Coulomb attraction plays an important role. While the on-site attraction, which has been used in previous numerical simulations, effectively renormalizes J for all values of x, an unphysical result, a nearest-neighbor range attraction renormalizes J only at very low dopings, i.e., until the bound holes wave functions start to overlap. Thus, our results indicate that the Coulomb attraction can be neglected to study Mn-doped GaSb, GaAs, and GaP in the relevant doping regimes, but it should be included in the case of Mn-doped GaN, which is expected to be in the IB regime.

  20. Developing Bisexual Attract-and-Kill for Polyphagous Insects: Ecological Rationale versus Pragmatics.

    PubMed

    Gregg, Peter C; Del Socorro, Alice P; Hawes, Anthony J; Binns, Matthew R

    2016-07-01

    We discuss the principles of bisexual attract-and-kill, in which females as well as males are targeted with an attractant, such as a blend of plant volatiles, combined with a toxicant. While the advantages of this strategy have been apparent for over a century, there are few products available to farmers for inclusion in integrated pest management schemes. We describe the development, registration, and commercialization of one such product, Magnet(®), which was targeted against Helicoverpa armigera and H. punctigera in Australian cotton. We advocate an empirical rather than theoretical approach to selecting and blending plant volatiles for such products, and emphasise the importance of field studies on ecologically realistic scales of time and space. The properties required of insecticide partners also are discussed. We describe the studies that were necessary to provide data for registration of the Magnet(®) product. These included evidence of efficacy, including local and area-wide impacts on the target pest, non-target impacts, and safety for consumers and applicators. In the decade required for commercial development, the target market for Magnet(®) has been greatly reduced by the widespread adoption of transgenic insect-resistant cotton in Australia. We discuss potential applications in resistance management for transgenic cotton, and for other pests in cotton and other crops. PMID:27380035

  1. Magnetic Refrigeration Development

    NASA Technical Reports Server (NTRS)

    Deardoff, D. D.; Johnson, D. L.

    1984-01-01

    Magnetic refrigeration is being developed to determine whether it may be used as an alternative to the Joule-Thomson circuit of a closed cycle refrigerator for providing 4 K refrigeration. An engineering model 4-15 K magnetic refrigerator has been designed and is being fabricated. This article describes the overall design of the magnetic refrigerator.

  2. Experimental signature of the attractive Coulomb force between positive and negative magnetic monopoles in spin ice

    NASA Astrophysics Data System (ADS)

    Paulsen, C.; Giblin, S. R.; Lhotel, E.; Prabhakaran, D.; Balakrishnan, G.; Matsuhira, K.; Bramwell, S. T.

    2016-07-01

    A non-Ohmic current that grows exponentially with the square root of applied electric field is well known from thermionic field emission (the Schottky effect), electrolytes (the second Wien effect) and semiconductors (the Poole-Frenkel effect). It is a universal signature of the attractive Coulomb force between positive and negative electrical charges, which is revealed as the charges are driven in opposite directions by the force of an applied electric field. Here we apply thermal quenches to spin ice to prepare metastable populations of bound pairs of positive and negative emergent magnetic monopoles at millikelvin temperatures. We find that the application of a magnetic field results in a universal exponential-root field growth of magnetic current, thus confirming the microscopic Coulomb force between the magnetic monopole quasiparticles and establishing a magnetic analogue of the Poole-Frenkel effect. At temperatures above 300 mK, gradual restoration of kinetic monopole equilibria causes the non-Ohmic current to smoothly evolve into the high-field Wien effect for magnetic monopoles, as confirmed by comparison to a recent and rigorous theory of the Wien effect in spin ice. Our results extend the universality of the exponential-root field form into magnetism and illustrate the power of emergent particle kinetics to describe far-from-equilibrium response in complex systems.

  3. Physical Attractiveness and Ethnicity: Implications for Stereotyping and Social Development.

    ERIC Educational Resources Information Center

    Stephan, Cookie White; Langlois, Judith H.

    1980-01-01

    In response to color slides of second grade children, 131 university students rated the children's physical attractiveness. Data suggest that the societal stereotype of black Americans was present in the evaluation of black children by black adults. Some indication of ethnocentrism among Anglo and Mexican-American adults was found. (Author/RH)

  4. High Temperature Superconducting Magnets with Active Control for Attraction Levitation Transport Applications

    NASA Technical Reports Server (NTRS)

    Jones, Harry; Jenkins, Richard G.; Goodall, Roger M.; Macleod, Colin; ElAbbar, Abdallah A.; Campbell, Archie M.

    1996-01-01

    A research program, involving 3 British universities, directed at quantifying the controllability of High Temperature Superconducting (HTS) magnets for use in attraction levitation transport systems will be described. The work includes measurement of loss mechanisms for iron cored HTS magnets which need to produce a flux density of approx. 1 tesla in the airgap between the magnet poles and a ferromagnetic rail. This flux density needs to be maintained and this is done by introducing small variations of the magnet current using a feedback loop, at frequencies up to 10 Hz to compensate for load changes, track variation etc. The test magnet assemblies constructed so far will be described and the studies and modelling of designs for a practical levitation demonstrator (using commercially obtained HTS tape) will be discussed with particular emphasis on how the field distribution and its components, e.g., the component vector normal to the broad face of the tape, can radically affect design philosophy compared to the classical electrical engineering approach. Although specifically aimed at levitation transport the controllability data obtained have implications for a much wider range of applications.

  5. Organic synthesis via magnetic attraction: benign and sustainable protocols using magnetic nanoferrites

    EPA Science Inventory

    Magnetic nano-catalysts have been prepared using simple modification of iron ferrites wherein their quasi-homogeneous state, because of nm size range, facilitates the catalysis process as increased surface is available for reaction; the easy separation of the catalysts by externa...

  6. Halbach Magnetic Rotor Development

    NASA Technical Reports Server (NTRS)

    Gallo, Christopher A.

    2008-01-01

    The NASA John H. Glenn Research Center has a wealth of experience in Halbach array technology through the Fundamental Aeronautics Program. The goals of the program include improving aircraft efficiency, reliability, and safety. The concept of a Halbach magnetically levitated electric aircraft motor will help reduce harmful emissions, reduce the Nation s dependence on fossil fuels, increase efficiency and reliability, reduce maintenance and decrease operating noise levels. Experimental hardware systems were developed in the GRC Engineering Development Division to validate the basic principles described herein and the theoretical work that was performed. A number of Halbach Magnetic rotors have been developed and tested under this program. A separate test hardware setup was developed to characterize each of the rotors. A second hardware setup was developed to test the levitation characteristics of the rotors. Each system focused around a unique Halbach array rotor. Each rotor required original design and fabrication techniques. A 4 in. diameter rotor was developed to test the radial levitation effects for use as a magnetic bearing. To show scalability from the 4 in. rotor, a 1 in. rotor was developed to also test radial levitation effects. The next rotor to be developed was 20 in. in diameter again to show scalability from the 4 in. rotor. An axial rotor was developed to determine the force that could be generated to position the rotor axially while it is rotating. With both radial and axial magnetic bearings, the rotor would be completely suspended magnetically. The purpose of this report is to document the development of a series of Halbach magnetic rotors to be used in testing. The design, fabrication and assembly of the rotors will be discussed as well as the hardware developed to test the rotors.

  7. Magnetic field dosimeter development

    SciTech Connect

    Lemon, D.K.; Skorpik, J.R.; Eick, J.L.

    1980-09-01

    In recent years there has been increased concern over potential health hazards related to exposure of personnel to magnetic fields. If exposure standards are to be established, then a means for measuring magnetic field dose must be available. To meet this need, the Department of Energy has funded development of prototype dosimeters at the Battelle Pacific Northwest Laboratory. This manual reviews the principle of operation of the dosimeter and also contains step-by-step instructions for its operation.

  8. A peristaltic micro pump driven by a rotating motor with magnetically attracted steel balls.

    PubMed

    Du, Min; Ye, Xiongying; Wu, Kang; Zhou, Zhaoying

    2009-01-01

    In this paper, we present a membrane peristaltic micro pump driven by a rotating motor with magnetically attracted steel balls for lab-on-a-chip applications. The fabrication process is based on standard soft lithography technology and bonding of a PDMS layer with a PMMA substrate. A linear flow rate range ∼490 μL/min was obtained by simply varying the rotation speed of a DC motor, and a maximum back pressure of 592 Pa was achieved at a rotation speed of 43 rpm. The flow rate of the pump can also be adjusted by using steel balls with different diameters or changing the number of balls. Nevertheless, the micro pump can also work in high speed mode. A high back pressure up to 10 kPa was achieved at 500 rpm using a high speed DC motor, and an utmost flow rate up to 5 mL/min was reached. PMID:22574035

  9. A Peristaltic Micro Pump Driven by a Rotating Motor with Magnetically Attracted Steel Balls

    PubMed Central

    Du, Min; Ye, Xiongying; Wu, Kang; Zhou, Zhaoying

    2009-01-01

    In this paper, we present a membrane peristaltic micro pump driven by a rotating motor with magnetically attracted steel balls for lab-on-a-chip applications. The fabrication process is based on standard soft lithography technology and bonding of a PDMS layer with a PMMA substrate. A linear flow rate range ∼490 μL/min was obtained by simply varying the rotation speed of a DC motor, and a maximum back pressure of 592 Pa was achieved at a rotation speed of 43 rpm. The flow rate of the pump can also be adjusted by using steel balls with different diameters or changing the number of balls. Nevertheless, the micro pump can also work in high speed mode. A high back pressure up to 10 kPa was achieved at 500 rpm using a high speed DC motor, and an utmost flow rate up to 5 mL/min was reached. PMID:22574035

  10. History and development of food-based attractants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adult tephrids require sugar and protein for survival and for development of eggs, and volatile chemicals from these substances are the basis for food-based lures developed as baits for these pests. In this chapter, we discuss food-based lures that mimic food sources for adults other than host fruit...

  11. Magnetic Suspension Technology Development

    NASA Technical Reports Server (NTRS)

    Britcher, Colin

    1998-01-01

    This Cooperative Agreement, intended to support focused research efforts in the area of magnetic suspension systems, was initiated between NASA Langley Research Center (LaRC) and Old Dominion University (ODU) starting January 1, 1997. The original proposal called for a three-year effort, but funding for the second year proved to be unavailable, leading to termination of the agreement following a 5-month no-cost extension. This report covers work completed during the entire 17-month period of the award. This research built on work that had taken place over recent years involving both NASA LARC and the Principal Investigator (PI). The research was of a rather fundamental nature, although specific applications were kept in mind at all times, such as wind tunnel Magnetic Suspension and Balance Systems (MSBS), space payload pointing and vibration isolation systems, magnetic bearings for unconventional applications, magnetically levitated ground transportation and electromagnetic launch systems. Fundamental work was undertaken in areas such as the development of optimized magnetic configurations, analysis and modelling of eddy current effects, control strategies for magnetically levitated wind tunnel models and system calibration procedures. Despite the termination of this Cooperative Agreement, several aspects of the research work are currently continuing with alternative forms of support.

  12. A 2 Tesla Full Scale High Performance Periodic Permanent Magnet Model for Attractive (228 KN) and repulsive Maglev

    NASA Technical Reports Server (NTRS)

    Stekly, Z. J. J.; Gardner, C.; Domigan, P.; Baker, J.; Hass, M.; McDonald, C.; Wu, C.; Farrell, R. A.

    1996-01-01

    Two 214.5 cm. long high performance periodic (26 cm period) permanent magnet half-assemblies were designed and constructed for use as a wiggler using Nd-B-Fe and vanadium permendur as hard and soft magnetic materials by Field Effects, a division of Intermagnetics General Corporation. Placing these assemblies in a supporting structure with a 2.1 cm pole to pole separation resulted in a periodic field with a maximum value of 2.04 T. This is believed to be the highest field ever achieved by this type of device. The attractive force between the two 602 kg magnet assemblies is 228 kN, providing enough force for suspension of a 45,500 kg vehicle. If used in an attractive maglev system with an appropriate flat iron rail, one assembly will generate the same force with a gap of 1.05 cm leading to a lift to weight ratio of 38.6, not including the vehicle attachment structure. This permanent magnet compares well with superconducting systems which have lift to weight ratios in the range of 5 to 10. This paper describes the magnet assemblies and their measured magnetic performance. The measured magnetic field and resulting attractive magnetic force have a negative spring characteristic. Appropriate control coils are necessary to provide stable operation. The estimated performance of the assemblies in a stable repulsive mode, with eddy currents in a conducting guideway, is also discussed.

  13. Discovery and Development of Chemical Attractants Used to Trap Pestiferous Social Wasps (Hymenoptera: Vespidae).

    PubMed

    Landolt, Peter; Zhang, Qing-He

    2016-07-01

    Chemical attractants for trapping temperate social wasps have been discovered during the screening of chemicals as attractants for flies, the study of pentatomid bug pheromones, and the testing of volatiles of fermented sweet baits. Wasp attraction to these chemicals seems to be related to either food-finding or prey-finding behavior. Of these attractive chemicals, commercial lures marketed in North America for trapping wasps generally contain heptyl butyrate, or the combination of acetic acid and 2-methyl-1-butanol. Heptyl butyrate is a very good attractant for two major pest wasp species in North America and minor wasp pests in the Vespula rufa species group. The combination of acetic acid with isobutanol attracted nearly all North American pest species of social wasps, including yellowjackets (Vespula and Dolichovespula), a hornet (Vespa crabro), and several paper wasps (Polistes spp.). The testing of wasp chemical attractants in different geographic areas demonstrated responses of many wasp taxa and showed a broad potential scope for the marketing of trap lures. Comparisons of compounds structurally similar to isobutanol revealed similar activity with 2-methyl-1-butanol, which is now used commercially because of a vapor pressure that is more favorable than isobutanol for formulations and dispensers. Doses and concentrations needed for good wasp catches were determined for heptyl butyrate, acetic acid, isobutanol, and 2-methyl-1-butanol, either formulated in water or dispensed from a controlled release device. Trap designs were developed based on consumer considerations; visual appeal, ease and safety of use, and low environmental impact. The resultant lures and traps are marketed in numerous physical and on-line retail outlets throughout the United States and southern Canada. PMID:27435228

  14. Attracting, Developing and Retaining Effective Teachers: Background Report for the United States

    ERIC Educational Resources Information Center

    Walsh, Kate; Wilcox, Danielle; Palmaffy, Tyce; Tracy, Christopher; Yiamouyiannis, Zeus; Ostermeier, Amy; Garcia, Lenore Yaffee

    2004-01-01

    This report presents a balanced picture of the debate on teacher quality in the U.S. and focuses on the aspects of teacher policy dealing with attracting, recruiting, developing and retaining effective teachers by synthesizing relevant research, identifying innovative and successful policy practices, facilitating exchanges of lessons among…

  15. Development of superconductive magnets

    NASA Technical Reports Server (NTRS)

    Laurence, J. C.

    1970-01-01

    Survey of superconductive magnets considers - stabilization problems, advances in materials and their uses, and design evolution. Uses of superconducting magnets in particle accelerators and bubble chambers, as well as possible applications in magnetohydrodynamic and thermonuclear power generation and levitation are discussed.

  16. Adventures in Fruit Fly Attractants – Multiple Phases of Bob Heath’s Research to Develop the Food-based Attractant for Tropical Tephritids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research was initiated in 1991 to develop a dry trap with female-targeted synthetic attractant for tropical tephritids to replace glass McPhail traps and liquid protein baits that had been the standard for over thirty years. Both the male-produced pheromone and the liquid protein baits were to be e...

  17. Developing Students' Ideas about Magnets

    ERIC Educational Resources Information Center

    Cheng, Meng-Fei

    2009-01-01

    This paper illustrates a series of activities designed to encourage fourth to sixth-grade students to develop their conceptions of magnets. Through scaffolding activities and facilitation from the teacher, students will be able to generate, evaluate, and refine their explanations for how magnets work. Students can gradually develop sophisticated…

  18. Mating attraction by Stenotus rubrovittatus (Heteroptera: Miridae) females and its relationship to ovarian development.

    PubMed

    Okutani-Akamatsu, Yasuyo; Watanabe, Tomonari; Azuma, Masaaki

    2007-08-01

    Stenotus rubrovittatus (Matsumura) (Heteroptera: Miridae) causes brown or black marks on rice, Oryza sativa L., grains (pecky rice), and it is becoming of increasing importance in Japan. Attractiveness of adult females or males of S. rubrovittatus to conspecific individuals was examined in the field in 2003 and 2004. Unmated female-baited traps captured significantly more males than did the unmated male-baited traps. However, the numbers of females captured by female- or male-baited traps were low, and they were not significantly different from the numbers caught by the control traps. No nymphs were captured by any traps. In 2004, we examined the effects of age and mating experience on female attraction ability with the goal of understanding the role of reproductive development in the observed behavior. The daily number of males captured by young unmated female (3-d-old)-baited traps increased from the first day until the fourth day of experiments, and then capture started to decrease. The peak in the number of captured males corresponded to the preoviposition period. When we observed ovarian development of S. rubrovittatus females under 25 degrees C and a photoperiod of 16:8 (L:D) h, we found that vitellogenesis had already started in approximately 30-50% of 1-d-old individuals. By the fifth day after emergence, 50-70% of individuals had mature eggs. These results indicated that the attractiveness of females is the strongest when egg laying becomes possible. Therefore, S. rubrovittatus females attract males selectively for mating, and it is probable that females use a sex pheromone for the attraction. PMID:17849880

  19. Science Can Be Attractive.

    ERIC Educational Resources Information Center

    Leyden, Michael B.

    1994-01-01

    Discusses the properties of neodymium magnets and magnets in general and how magnets can be used to teach students important scientific principles, such as attraction, repulsion, and polarity; the role of magnetic forces in electronic communications and computers; the magnetic properties of the earth and compasses; and the relationship between…

  20. Flywheel Magnetic Suspension Developments

    NASA Technical Reports Server (NTRS)

    Palazzolo, Alan; Kenny, Andrew; Sifford, Curtiss; Thomas, Erwin; Bhuiyan, Mohammad; Provenza, Andrew; Kascak, Albert; Montague, Gerald; Lei, Shuliang; Kim, Yeonkyu; Sun, Guangyoung; Chon, ChonHee; Tucker, Randy; Preuss, Jason; Li, Ming; Minihan, Thomas

    2002-01-01

    The paper provides an overview of many areas of the flywheel magnetic suspension (MS) R&D being performed at the Texas A&M Vibration Control and Electromechanics Lab (TAMU-VCEL). This includes system response prediction, actuator optimization and redundancy, controller realizations and stages, sensor enhancements and backup bearing reliability.

  1. Feasibility of using high temperature superconducting magnets and conventional magnetic loop antennas to attract or repel objects at the space station

    NASA Astrophysics Data System (ADS)

    Randhawa, Manjit S.

    1989-02-01

    A study was undertaken to see if magnetic forces can be used at the Space Station to attract or repel spacecrafts such as the Orbital Manuevering Vehicle (OMV) or the Orbiter. A large magnet, in the form of a current loop, is assumed to be placed at the Space Station and another one on the spacecraft. The expression for the force between the two dipoles (loops) is obtained. Using a force of 15 Newtons (3.4 pounds) in order to move the spacecraft, the number of ampere-turn needed in the current loops was calculated at various distances between them. The expression for the force of attraction between a current loop and a soft magnetic material was also examined and the number of amp-turn needed to provide a force of one-tenth of a pound at various distances is also calculated. This one tenth of a pound force would be used in a life line system for the retrieval of an adrift crewman or tool at the Space Station. The feasibility of using conventional antenna on the Station and the incoming vehicle for attraction or repulsion was also examined.

  2. Feasibility of using high temperature superconducting magnets and conventional magnetic loop antennas to attract or repel objects at the space station

    NASA Technical Reports Server (NTRS)

    Randhawa, Manjit S.

    1989-01-01

    A study was undertaken to see if magnetic forces can be used at the Space Station to attract or repel spacecrafts such as the Orbital Manuevering Vehicle (OMV) or the Orbiter. A large magnet, in the form of a current loop, is assumed to be placed at the Space Station and another one on the spacecraft. The expression for the force between the two dipoles (loops) is obtained. Using a force of 15 Newtons (3.4 pounds) in order to move the spacecraft, the number of ampere-turn needed in the current loops was calculated at various distances between them. The expression for the force of attraction between a current loop and a soft magnetic material was also examined and the number of amp-turn needed to provide a force of one-tenth of a pound at various distances is also calculated. This one tenth of a pound force would be used in a life line system for the retrieval of an adrift crewman or tool at the Space Station. The feasibility of using conventional antenna on the Station and the incoming vehicle for attraction or repulsion was also examined.

  3. How Magnets Attract and Repel: Interessement in a Technology Commercialization Competition

    ERIC Educational Resources Information Center

    Spinuzzi, Clay; Nelson, Scott; Thomson, Keela S.; Lorenzini, Francesca; French, Rosemary A.; Pogue, Gregory; London, Noelle

    2016-01-01

    K6015, a South Korean firm seeking to commercialize its magnet technology in the US market, entered a technology commercialization training program structured as a competition. Through this program, K6015 (and others in the program) used several genres to progressively interest different sets of stakeholders. To understand how K6015 applied these…

  4. Attracting Diverse Students to a Magnet School: Risking Aspirations or Swallowing One's Beliefs

    ERIC Educational Resources Information Center

    Taggart, Amanda; Shoho, Alan R.

    2013-01-01

    This case study focuses on the ethics of advocating for a social justice perspective versus jeopardizing one's career aspirations. There are numerous subplots to this case involving the start-up of a new magnet school, including its leaders' concerns for meeting accountability measures and representing racially diverse, limited English proficient,…

  5. Magnetic attraction leading to a small bowel obstruction in a child.

    PubMed

    Fenton, Stephen J; Torgenson, Marcus; Holsti, Maija; Black, Richard E

    2007-12-01

    Foreign body ingestion in small children is common yet only 1% of cases require operative management of associated complications (Arana et al. in Eur J Pediatr 160:468-472, 2001). A 6-year-old boy was referred to our institution with a 12 h history of abdominal pain. This pain was diffuse and crampy in nature and associated with multiple episodes of non-bilious, non-bloody emesis. On evaluation he was stable and his abdomen demonstrated slight distention and tenderness without peritoneal signs. Plain abdominal radiographs demonstrated some distended loops of small bowel and a radio-opaque foreign object within the mid-abdomen. A small bowel obstruction secondary to foreign body ingestion was diagnosed and an emergent laparotomy performed. Upon exploration, a transition zone was noted near the ileocecal valve. Further exploration revealed the obstruction to be caused secondary to the apposition of two small (8 mm) magnets, one in the proximal ileum and the other near the ileocecal valve, resulting in an internal hernia. The magnets were easily separated relieving the obstruction and both were removed via two small bowel enterotomies. After being presented with the magnets, his parents suspected that they came from the clothes of a Polly Pocket (Mattel, Inc., El Segundo, CA) doll. The patient had an uneventful post-operative course and was discharged to home on the second post-operative day. This case demonstrates the complications that may occur with multiple magnet ingestion. It highlights the need for close observation and early surgical intervention in children with a suspected history of foreign body ingestion, a clinical picture of gastrointestinal distress, and radiographic evidence of a radio-opaque foreign object. PMID:17694401

  6. [Development and transition of magnetic attachments--a literature review].

    PubMed

    Hirata, M

    1997-12-01

    In the 1950 s, a new method of using magnets for the retainers of removable partial dentures (RPDs) was developed. It utilized magnetic attractive force instead of mechanical friction. However, the magnets used in those days were Alnico, Ferrite and/or Pt-Cobalt magnets and their retentive force was not strong enough to stabilize the dentures. Therefore, they gradually went out of use. In the middle of the 1970 s, Samarium Cobalt magnets, which have strong magnetic characteristics, were developed and introduced into dental field. In 1976, Sasaki first applied the samarium cobalt magnets to the retainers of PPDs. While in 1981, Mizutani, et al. first used well-fitted ferromagnetic alloy and the magnet for the purpose of stabilizing the RPD. Since then, many researchers have developed devices such as the magnetic retainer and the closed field magnetic attachment placed on the market in 1992. Now, as for the popular retainer of RPD, one can easily use a smaller yet stronger magnetic attachment which uses Neodium rather than Samarium Cobalt magnet. PMID:9483897

  7. Attracting, Developing, and Maintaining Human Capital: A New Model for Economic Development

    ERIC Educational Resources Information Center

    America's Promise Alliance (NJ1), 2011

    2011-01-01

    "Investing in Kids: Early Childhood Programs and Local Economic Development," a 2011 book by Timothy Bartik, Senior Economist at the W.E. Upjohn Institute for Employment Research, provides a new evidence-based approach for effective economic development. This approach is designed to support business growth and job creation by improving worker…

  8. Vancomycin-sensitive bacteria trigger development of colitis-associated colon cancer by attracting neutrophils.

    PubMed

    Tanaka, Yuriko; Ito, Sachiko; Isobe, Ken-ichi

    2016-01-01

    Inflammatory bowel disease confers an increased risk of developing colitis-associated colon cancer (CAC). During the active colitis or developing tumor stage, commensal bacteria show dynamic translocation. However, whether alteration of the bacterial composition in the gut causes CAC is still unclear. To clarify the effect of commensal bacteria on CAC development, we employed an azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced murine CAC model treated with or without antibiotics. In addition, we analyzed the effects of antibiotics on infiltration of myeloid cells, colonic inflammatory responses, and colorectal cancer formation. We found that vancomycin treatment dramatically suppressed tumor development. In addition, AOM/DSS treatment greatly induced the infiltration of Gr-1(high)/CD11b(high) neutrophils to the colon, which led to the production of tumor necrosis factor α and inducible nitric oxide synthase. Vancomycin treatment suppressed the infiltration of neutrophils induced by AOM/DSS. Moreover, vancomycin treatment greatly reduced the colon injury and DNA damage caused by AOM/DSS-induced NO radicals. Our results indicate that vancomycin-sensitive bacteria induced colon inflammation and DNA damage by attracting neutrophils into damaged colon tissue, thus promoting tumor formation. PMID:27050089

  9. Vancomycin-sensitive bacteria trigger development of colitis-associated colon cancer by attracting neutrophils

    PubMed Central

    Tanaka, Yuriko; Ito, Sachiko; Isobe, Ken-ichi

    2016-01-01

    Inflammatory bowel disease confers an increased risk of developing colitis-associated colon cancer (CAC). During the active colitis or developing tumor stage, commensal bacteria show dynamic translocation. However, whether alteration of the bacterial composition in the gut causes CAC is still unclear. To clarify the effect of commensal bacteria on CAC development, we employed an azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced murine CAC model treated with or without antibiotics. In addition, we analyzed the effects of antibiotics on infiltration of myeloid cells, colonic inflammatory responses, and colorectal cancer formation. We found that vancomycin treatment dramatically suppressed tumor development. In addition, AOM/DSS treatment greatly induced the infiltration of Gr-1high/CD11bhigh neutrophils to the colon, which led to the production of tumor necrosis factor α and inducible nitric oxide synthase. Vancomycin treatment suppressed the infiltration of neutrophils induced by AOM/DSS. Moreover, vancomycin treatment greatly reduced the colon injury and DNA damage caused by AOM/DSS-induced NO radicals. Our results indicate that vancomycin-sensitive bacteria induced colon inflammation and DNA damage by attracting neutrophils into damaged colon tissue, thus promoting tumor formation. PMID:27050089

  10. Attracting IPPs

    SciTech Connect

    Burr, M.T.

    1995-10-01

    Brazil faces a need to expand electric generation capacity by 25 gigawatts (GW) through the year 2004. This means that about 10,350 MW plants need to be installed during each of the next eight years. The situation is particularly serious in the populous, industrialized south and southeastern regions. As a result, the new government is taking measures to attract private power developers and accelerate privatization. This progress is encouraging, but a number of fundamental issues must be addressed before IPPs can begin meeting the power demands. Stumbling blocks remain: regulatory hurdles, market imbalances, credit worthiness concerns and a history of political and economic volatility.

  11. Development of a mosquito attractant blend of small molecules against host-seeking Aedes aegypti.

    PubMed

    Saratha, R; Mathew, Nisha

    2016-04-01

    A mosquito's dependence on olfaction in the hunt for human host could be efficiently exploited to protect humans from mosquito bites. The present study is undertaken to make the most attractant compound blend for Aedes aegypti mosquitoes to lure them to traps. Eleven molecules (M1-M11) at different dilutions were screened for attractancy against non-blood-fed adult female mosquitoes in an olfactometer. The results showed that the attractancy was dependent on both the chemical nature of the molecule and the strength of the odor. Out of 11 molecules screened, 9 showed significant attractancy (P < 0.05) when tested individually. The attractancy was in the order of M11 > M7 > M6 > M10 > M9 > M3 > M2 > M1 > M4 with attractancy indices (AIs) 86.11, 55.93, 55.17, 54, 52.94, 52, 50, 43.64, and 32, respectively, at the optimum dilutions. Seven blends (I-VII) were made and were screened for attractancy against Ae. aegypti. All the blends showed significant attractancy (P < 0.05). The attractancy was in the order of blend VII > III > IV > I > VI > V > II with AIs 96.63, 89.19, 65, 57.89, 56.1, 47.13, and 44.44, respectively. Among the seven blends, blend VII with constituent molecules M6, M9, M10, and M11 is the most promising with an AI value of 96.63. This blend will be useful in luring the host-seeking mosquitoes to traps. The field efficacy of these attractant blends may be explored in the future. PMID:26693718

  12. The financial attractiveness assessment of large waste management projects registered as clean development mechanism

    SciTech Connect

    Bufoni, André Luiz

    2015-09-15

    Highlights: • Projects are not financially attractive without registration as CDMs. • WM benchmarks and indicators are converging and reducing in variance. • A sensitivity analysis reveal that revenue has more of an effect on the financial results. • Results indicate that an extensive database would reduce WM project risk and capital costs. • Disclosure standards would make information more comparable worldwide. - Abstract: This study illustrates the financial analyses for demonstration and assessment of additionality presented in the project design (PDD) and enclosed documents of the 431 large Clean Development Mechanisms (CDM) classified as the ‘waste handling and disposal sector’ (13) over the past ten years (2004–2014). The expected certified emissions reductions (CER) of these projects total 63.54 million metric tons of CO{sub 2}eq, where eight countries account for 311 projects and 43.36 million metric tons. All of the projects declare themselves ‘not financially attractive’ without CER with an estimated sum of negative results of approximately a half billion US$. The results indicate that WM benchmarks and indicators are converging and reducing in variance, and the sensitivity analysis reveals that revenues have a greater effect on the financial results. This work concludes that an extensive financial database with simple standards for disclosure would greatly diminish statement problems and make information more comparable, reducing the risk and capital costs of WM projects.

  13. The financial attractiveness assessment of large waste management projects registered as clean development mechanism.

    PubMed

    Bufoni, André Luiz; Oliveira, Luciano Basto; Rosa, Luiz Pinguelli

    2015-09-01

    This study illustrates the financial analyses for demonstration and assessment of additionality presented in the project design (PDD) and enclosed documents of the 431 large Clean Development Mechanisms (CDM) classified as the 'waste handling and disposal sector' (13) over the past ten years (2004-2014). The expected certified emissions reductions (CER) of these projects total 63.54 million metric tons of CO2eq, where eight countries account for 311 projects and 43.36 million metric tons. All of the projects declare themselves 'not financially attractive' without CER with an estimated sum of negative results of approximately a half billion US$. The results indicate that WM benchmarks and indicators are converging and reducing in variance, and the sensitivity analysis reveals that revenues have a greater effect on the financial results. This work concludes that an extensive financial database with simple standards for disclosure would greatly diminish statement problems and make information more comparable, reducing the risk and capital costs of WM projects. PMID:26123976

  14. Slip instability development and earthquake nucleation as a dynamical system's fixed-point attraction

    NASA Astrophysics Data System (ADS)

    Viesca, R. C.

    2014-12-01

    A fault's transition from slow creep to the propagation of an earthquake-generating dynamic rupture is thought to start as a quasi-static slip instability. Here we examine how such an instability develops on a sliding interface whose strength is governed by a slip rate- and state-dependent friction, where the state variable evolves according to the aging law. We find that the development occurs as the attraction of a dynamical system to a fixed point. The fixed points are such that the state of slip and the rate at which velocity diverges (and its spatial distribution) are known. The fixed points are independent of the manner of external forcing and the values of slip rate and state before the onset of instability. For a fault under uniform normal stress and frictional properties, the sole parameter that determines the fixed point (to within a translational invariance) is the ratio of the frictional parameters, a/b (where, for steady-state rate weakening, 0develop in a chaotic fashion. The fixed-point solutions, as well as the critical thresholds concerning their stability, depend on the configuration of slip (e.g., in/anti-plane or mixed-mode slip) and the elastic environment in which the interface is embedded (e.g., a slip surface between elastic half-spaces or one lying below and parallel to a free surface); solving for a fixed point reduces to the solution of an equivalent problem of an equilibrium slip-weakening fracture; and fixed-point stability is determined by linear stability analysis. Solutions of

  15. Facial attractiveness.

    PubMed

    Thornhill; Gangestad

    1999-12-01

    Humans in societies around the world discriminate between potential mates on the basis of attractiveness in ways that can dramatically affect their lives. From an evolutionary perspective, a reasonable working hypothesis is that the psychological mechanisms underlying attractiveness judgments are adaptations that have evolved in the service of choosing a mate so as to increase gene propagation throughout evolutionary history. The main hypothesis that has directed evolutionary psychology research into facial attractiveness is that these judgments reflect information about what can be broadly defined as an individual's health. This has been investigated by examining whether attractiveness judgments show special design for detecting cues that allow us to make assessments of overall phenotypic condition. This review examines the three major lines of research that have been pursued in order to answer the question of whether attractiveness reflects non-obvious indicators of phenotypic condition. These are studies that have examined facial symmetry, averageness, and secondary sex characteristics as hormone markers. PMID:10562724

  16. The discovery and development of chemical attractants used to trap pestiferous wasps (Hymenoptera: Vespidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Social wasps are a stinging hazard, including in fruit crops where they also do direct feeding damage to trees and fruits, and at tall structures such as towers where some species form mating and overwintering aggregations. Chemical attractants are of use against these wasps as lures for traps and b...

  17. Developing tools to eradicate ecologically destructive ants on Rose Atoll: effectiveness and attractiveness of formicidal baits

    USGS Publications Warehouse

    Peck, Robert; Banko, Paul; Pendleton, Frank

    2014-01-01

    A key factor contributing to the decline in the population of Pisonia grandis on Rose Atoll is an infestation of the non-native scale, Pulvinaria urbicola (Homoptera: Coccidae). Ants, in facultative relationships with scale insects, may facilitate scale population growth and increase their effect on plant hosts. Three ant species found on Rose Atoll, Tetramorium bicarinatum, T. simillimum, and Pheidole oceanica, are capable of tending Pulvinaria on Pisonia and may have contributed to the demise of the trees on the atoll. Replicated trials conducted on Rose Atoll during 17–21 March 2013 tested the effectiveness and relative attractiveness of five formicidal baits potentially to be used to eradicate these ants on the atoll. Three baits contained toxins (hydramethylnon in Amdro® and Maxforce®, indoxacarb in Provaunt®) and two baits contained an insect growth regulator (IGR; pyriproxyfen in Distance® and s-methoprene in Tango®). Amdro, Distance, and Maxforce are granular baits while Provaunt and Tango were mixed with adjuvants to form a gel-like matrix. Results varied among ant species and baits, but Provaunt was highly effective against workers of both Tetramorium species while Amdro and Maxforce were highly effective against T. simillimum and P. oceanica. Limited time on the island prevented the evaluation of the effectiveness of the IGR baits. The relative attractiveness of the baits generally mirrored their ability to kill worker ants. Tetramorium simillimum was attracted to all five baits; T. bicarinatum was attracted to Provaunt, Distance, and Tango; and P. oceanica was attracted to the three granular baits. These results and the small area of Rose Atoll suggest that island-wide application of formicidal baits may result in eradication of these ants, but an application strategy targeting all three species would more likely succeed with the use of multiple baits.

  18. Nb3Sn accelerator magnet development around the world

    SciTech Connect

    Michael J. Lamm

    2003-06-23

    During the past 30 years superconducting magnet systems have enabled accelerators to achieve energies and luminosities that would have been impractical if not impossible with resistive magnets. By far, NbTi has been the preferred conductor for this application because of its ductility and insensitivity of Jc to mechanical strain. This is despite the fact that Nb{sub 3}Sn has a more favorable Jc vs. B dependence and can operate at much higher temperatures. Unfortunately, NbTi conductor is reaching the limit of it usefulness for high field applications. Despite incremental increases in Jc and operation at superfluid temperatures, magnets are limited to approximately a 10 T field. Improvements in conductor performance combined with future requirements for accelerator magnets to have bore fields greater than 10 T or operate in areas of large beam-induced heat loads now make Nb{sub 3}Sn look attractive. Thus, laboratories in several countries are actively engaged in programs to develop Nb{sub 3}Sn accelerator magnets for future accelerator applications. A summary of this important research activity is presented along with a brief history of Nb{sub 3}Sn accelerator magnet development and a discussion of requirements for future accelerator magnets.

  19. Development of a magnetically suspended momentum wheel

    NASA Technical Reports Server (NTRS)

    Hamilton, S. B.

    1973-01-01

    An engineering model of a magnetically suspended momentum wheel was designed, fabricated, and tested under laboratory conditions. The basic unit consisted of two magnet bearings, a sculptured aluminum rotor, brushless dc spin motor, and electronics. The magnet bearings, utilizing rare-earth cobltrat-samarium magnets were active radially and passive axially. The results of the program showed that momentum wheels with magnetic bearings are feasible and operable, and that magnetic bearings of this type are capable of being used for applications where high capacity, high stiffness, and low power consumption are required. The tests performed developed criteria for improved performance for future designs.

  20. Present Status of the KSTAR Superconducting Magnet System Development

    NASA Astrophysics Data System (ADS)

    Kim, Keeman; H, K. Park; K, R. Park; B, S. Lim; S, I. Lee; M, K. Kim; Y, Chu; W, H. Chung; S, H. Baek; J Y, Choi; H, Yonekawa; A, Chertovskikh; Y, B. Chang; J, S. Kim; C, S. Kim; D, J. Kim; N, H. Song; K, P. Kim; Y, J. Song; I, S. Woo; W, S. Han; D, K. Lee; Y, K. Oh; K, W. Cho; J, S. Park; G, S. Lee; H, J. Lee; T, K. Ko; S, J. Lee

    2004-10-01

    The mission of Korea Superconducting Tokamak Advanced Research (KSTAR) project is to develop an advanced steady-state superconducting tokamak for establishing a scientific and technological basis for an attractive fusion reactor. Because one of the KSTAR mission is to achieve a steady-state operation, the use of superconducting coils is an obvious choice for the magnet system. The KSTAR superconducting magnet system consists of 16 Toroidal Field (TF) coils and 14 Poloidal Field (PF) coils. Internally-cooled Cable-In-Conduit Conductors (CICC) are put into use in both the TF and PF coil systems. The TF coil system provides a field of 3.5 T at the plasma center and the PF coil system is able to provide a flux swing of 17 V-sec. The major achievement in KSTAR magnet-system development includes the development of CICC, the development of a full-size TF model coil, the development of a coil system for background magnetic-field generation, the construction of a large-scale superconducting magnet and CICC test facility. TF and PF coils are in the stage of fabrication to pave the way for the scheduled completion of KSTAR by the end of 2006.

  1. Eigenvalue Attraction

    NASA Astrophysics Data System (ADS)

    Movassagh, Ramis

    2016-02-01

    We prove that the complex conjugate (c.c.) eigenvalues of a smoothly varying real matrix attract (Eq. 15). We offer a dynamical perspective on the motion and interaction of the eigenvalues in the complex plane, derive their governing equations and discuss applications. C.c. pairs closest to the real axis, or those that are ill-conditioned, attract most strongly and can collide to become exactly real. As an application we consider random perturbations of a fixed matrix M. If M is Normal, the total expected force on any eigenvalue is shown to be only the attraction of its c.c. (Eq. 24) and when M is circulant the strength of interaction can be related to the power spectrum of white noise. We extend this by calculating the expected force (Eq. 41) for real stochastic processes with zero-mean and independent intervals. To quantify the dominance of the c.c. attraction, we calculate the variance of other forces. We apply the results to the Hatano-Nelson model and provide other numerical illustrations. It is our hope that the simple dynamical perspective herein might help better understanding of the aggregation and low density of the eigenvalues of real random matrices on and near the real line respectively. In the appendix we provide a Matlab code for plotting the trajectories of the eigenvalues.

  2. Online learning and control of attraction basins for the development of sensorimotor control strategies.

    PubMed

    de Rengervé, Antoine; Andry, Pierre; Gaussier, Philippe

    2015-04-01

    Imitation and learning from humans require an adequate sensorimotor controller to learn and encode behaviors. We present the Dynamic Muscle Perception-Action(DM-PerAc) model to control a multiple degrees-of-freedom (DOF) robot arm. In the original PerAc model, path-following or place-reaching behaviors correspond to the sensorimotor attractors resulting from the dynamics of learned sensorimotor associations. The DM-PerAc model, inspired by human muscles, permits one to combine impedance-like control with the capability of learning sensorimotor attraction basins. We detail a solution to learn incrementally online the DM-PerAc visuomotor controller. Postural attractors are learned by adapting the muscle activations in the model depending on movement errors. Visuomotor categories merging visual and proprioceptive signals are associated with these muscle activations. Thus, the visual and proprioceptive signals activate the motor action generating an attractor which satisfies both visual and proprioceptive constraints. This visuomotor controller can serve as a basis for imitative behaviors. In addition, the muscle activation patterns can define directions of movement instead of postural attractors. Such patterns can be used in state-action couples to generate trajectories like in the PerAc model. We discuss a possible extension of the DM-PerAc controller by adapting the Fukuyori's controller based on the Langevin's equation. This controller can serve not only to reach attractors which were not explicitly learned, but also to learn the state/action couples to define trajectories. PMID:25576394

  3. Acoustic Attraction

    NASA Astrophysics Data System (ADS)

    Oviatt, Eric; Patsiaouris, Konstantinos; Denardo, Bruce

    2009-11-01

    A sound source of finite size produces a diverging traveling wave in an unbounded fluid. A rigid body that is small compared to the wavelength experiences an attractive radiation force (toward the source). An attractive force is also exerted on the fluid itself. The effect can be demonstrated with a styrofoam ball suspended near a loudspeaker that is producing sound of high amplitude and low frequency (for example, 100 Hz). The behavior can be understood and roughly calculated as a time-averaged Bernoulli effect. A rigorous scattering calculation yields a radiation force that is within a factor of two of the Bernoulli result. For a spherical wave, the force decreases as the inverse fifth power of the distance from the source. Applications of the phenomenon include ultrasonic filtration of liquids and the growth of supermassive black holes that emit sound waves in a surrounding plasma. An experiment is being conducted in an anechoic chamber with a 1-inch diameter aluminum ball that is suspended from an analytical balance. Directly below the ball is a baffled loudspeaker that exerts an attractive force that is measured by the balance.

  4. Development of a CO2 releasing co-formulation 1 based on starch, Saccharomyces cerevisiae and Beauveria bassiana attractive towards western corn rootworm larvae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    CO2 is known as an attractant for many soil-dwelling pests. To implement an attract-and-kill strategy for soil pest control, CO2 emitting formulations need to be developed. This work aimed at the development of a slow release bead system in order to bridge the gap between application and hatching of...

  5. An Application of Project-Based Learning on the Development of Young Local Tour Guides on Tai Phuan's Culture and Tourist Attractions in Sisatchanalai District, Sukhothai Province

    ERIC Educational Resources Information Center

    Kerdpol, Sakon

    2016-01-01

    This paper presents an investigation of a research entitled, " An Application of Project-based Learning on the Development of Young Local Tour Guides on Tai Phuan's Culture and Tourist Attractions in Sisatchanalai District, Sukhothai Province. It was intended to develop young local tour guides on Tai Phuan's culture and tourist attractions in…

  6. Development of high temperature superconductors for magnetic field applications

    NASA Astrophysics Data System (ADS)

    Larbalestier, D. C.

    The key requirement for magnetic field applications of high temperature superconductor (HTS) materials is to have conductors with high transport critical current density available for magnet builders. After 3 or 4 years of being without any such object, conductor makers have had recent success in producing simple conductor prototypes. These have permitted the construction of simple HTS magnets having self fields exceeding 1 tesla at 4K. Thus the scientific feasibility of making powerful HTS magnets has been demonstrated. Attention to the technological aspects of making HTS conductors for magnets with strong flux pinning and reduced superconducting granularity is now sensible and attractive. However, extrinsic defects such as filament sausaging, cracking, misaligned grains and other perturbation to long range current flow must be controlled at a low level if the benefit of intrinsic improvements to the critical current density is to be maintained in the conductor form. Due to the great complexity of the HTS materials, there is sometimes confusion as to whether a given sample has an intrinsically or extrinsically limited critical current density. Systematic microstructure variation experiments and resistive transition analysis are shown to be particularly helpful in this phase of conductor development.

  7. Development of high temperature superconductors for magnetic field applications

    SciTech Connect

    Larbalestier, D.C.

    1991-12-31

    The key requirement for magnetic field applications of high temperature superconductor (HTS) materials is to have conductors with high transport critical current density available for magnet builders. After 3 or 4 years of being without any such object, conductor makers have had recent success in producing simple conductor prototypes. These have permitted the construction of simple HTS magnets having self fields exceeding 1 tesla at 4K. Thus the scientific feasibility of making powerful HTS magnets has been demonstrated. Attention to the technological aspects of making HTS conductors for magnets with strong flux pinning and reduced superconducting granularity is now sensible and attractive. However, extrinsic defects such as filament sausaging, cracking, misaligned grains and other perturbation to long range current flow must be controlled at a low level if the benefit of intrinsic improvements to the critical current density is to be maintained in the conductor form. Due to the great complexity of the HTS materials, there is sometimes confusion as to whether a given sample has an intrinsically or extrinsically limited critical current density. Systematic microstructure variation experiments and resistive transition analysis are shown to be particularly helpful in this phase of conductor development.

  8. Development of high temperature superconductors for magnetic field applications

    SciTech Connect

    Larbalestier, D.C.

    1991-01-01

    The key requirement for magnetic field applications of high temperature superconductor (HTS) materials is to have conductors with high transport critical current density available for magnet builders. After 3 or 4 years of being without any such object, conductor makers have had recent success in producing simple conductor prototypes. These have permitted the construction of simple HTS magnets having self fields exceeding 1 tesla at 4K. Thus the scientific feasibility of making powerful HTS magnets has been demonstrated. Attention to the technological aspects of making HTS conductors for magnets with strong flux pinning and reduced superconducting granularity is now sensible and attractive. However, extrinsic defects such as filament sausaging, cracking, misaligned grains and other perturbation to long range current flow must be controlled at a low level if the benefit of intrinsic improvements to the critical current density is to be maintained in the conductor form. Due to the great complexity of the HTS materials, there is sometimes confusion as to whether a given sample has an intrinsically or extrinsically limited critical current density. Systematic microstructure variation experiments and resistive transition analysis are shown to be particularly helpful in this phase of conductor development.

  9. Proximity detector circuits: an attractive alternative to tunnel diode oscillators for contactless measurements in pulsed magnetic fields

    SciTech Connect

    Altarawneh, Moaz M; Mielke, Charles H

    2009-01-01

    A new radio frequency oscillator circuit based on a proximity detector integrated circuit is described as an alternative for the traditional tunnel diode oscillator used for pulsed magnetic field measurements at low temperatures. The new circuit has been successfully applied to measure the superconducting upper critical field in Ba{sub 0.55}K{sub 0.45}Fe{sub 2}As{sub 2} single crystfl.ls up to 60 T. The new circuit design avoids many of the problems associated with tunnel diode circuits while keeping the advantages of contact less measurements in pulsed magnets.

  10. Attractiveness and Psychological Development. Teacher Education Forum; Volume 4, Number 21.

    ERIC Educational Resources Information Center

    Algozzine, Robert; Salvia, John

    An investigation of the relationship between appearance and psychological development is presented in this paper. The central hypothesis of the investigation is that appearance is an important stimulus property in the psychological development of children, and as such has an effect on an individual's response to his environment as well as the…

  11. Electromagnetic Attraction.

    ERIC Educational Resources Information Center

    Milson, James L.

    1990-01-01

    Three activities involving electromagnetism are presented. Discussed are investigations involving the construction of an electromagnet, the effect of the number of turns of wire in the magnet, and the effect of the number of batteries in the circuit. Extension activities are suggested. (CW)

  12. Development of electroplated magnetic materials for MEMS

    NASA Technical Reports Server (NTRS)

    Myung, N. V.; Sumadjo, P. T. A.; Park, D. Y.

    2002-01-01

    Soft ferromagnetic materials have thus far found the most utility in magnetic-MEMS, because the technologies necessary for depositing and micromachining them have been well developed previously by the data storage industry.

  13. Development of HTS magnets for application

    NASA Astrophysics Data System (ADS)

    Hatanaka, Kichiji; Fukuda, Mitsuhiro; Yorita, Tetsuhiko; Ueda, Hiroshi; Yasuda, Yuusuke; Kamakura, Keita; Morita, Yoshiya; Yamane, Hiroyoshi; Kawaguchi, Takeo

    2014-09-01

    We have been developing magnets utilizing high-temperature superconducting (HTS) wires for this decade. We built three model magnets, a mirror coil for an ECR ion source, a set of coils for a scanning magnet and a super-ferric dipole magnet to generate magnetic field of 3 T. They were excited with AC/pulse currents as well as DC currents. Recently we fabricated a cylindrical magnet for a practical use which polarizes ultracold neutrons (UCN). It consists of 10 double pancakes and the field strength at the center is higher than 3.5 T which is required to fully polarize 210 neV neutrons. It was successfully cooled and excited. The magnet was used to polarized UCN generated by the RCNP-KEK superthermal UCN source, One dipole magnet has been manufactured which is used as a switching magnet after the RCNP ring cyclotron and is excited by pulse currents. It becomes possible to deliver beams to two experimental halls by time sharing. Their designs and performances are presented in the talk.

  14. Electrochemical separation is an attractive strategy for development of radionuclide generators for medical applications.

    PubMed

    Chakravarty, Rubel; Dash, Ashutosh; Pillai, M R A

    2012-07-01

    Electrochemical separation techniques are not widely used in radionuclide generator technology and only a few studies have been reported [1-4]. Nevertheless, this strategy is useful when other parent-daughter separation techniques are not effective or not possible. Such situations are frequent when low specific activity (LSA) parent radionuclides are used for instance with adsorption chromatographic separations, which can result in lower concentration of the daughter radionuclide in the eluent. In addition, radiation instability of the column matrix in many cases can affect the performance of the generator when long lived parent radionuclides are used. Intricate knowledge of the chemistry involved in the electrochemical separation is crucial to develop a reproducible technology that ensures that the pure daughter radionuclide can be obtained in a reasonable time of operation. Crucial parameters to be critically optimized include the applied potential, choice of electrolyte, selection of electrodes, temperature of electrolyte bath and the time of electrolysis in order to ensure that the daughter radionuclide can be reproducibly recovered in high yields and high purity. The successful electrochemical generator technologies which have been developed and are discussed in this paper include the (90)Sr/(90)Y, (188)W/(188)Re and (99)Mo/(99m)Tc generators. Electrochemical separation not only acts as a separation technique but also is an effective concentration methodology which yields high radioactive concentrations of the daughter products. The lower consumption of reagents and minimal generation of radioactive wastes using such electrochemical techniques are compatible with 'green chemistry' principles. PMID:22642386

  15. Development of a complex floral trait: The pollinator-attracting petal spots of the beetle daisy, Gorteria diffusa (Asteraceae).

    PubMed

    Thomas, Meredith M; Rudall, Paula J; Ellis, Allan G; Savolainen, Vincent; Glover, Beverley J

    2009-12-01

    Angiosperms possess a variety of complex floral traits that attract animal pollinators. Dark petal spots have evolved independently many times across the angiosperm phylogeny and have been shown to attract insect pollinators from several lineages. Here we present new data on the ontogeny and morphological complexity of the elaborate insect-mimicking petal spots of the South African daisy species, Gorteria diffusa (Asteraceae), commonly known as the beetle daisy, although it is fly-pollinated. Using light and scanning electron microscopy and histology, we identified three distinct specialized cell types of the petal epidermis that compose the petal spot. Sophisticated patterning of pigments, cuticular elaborations, and multicellular papillate trichomes make the G. diffusa petal spot a uniquely complex three-dimensional floral ornament. Examination of young inflorescence meristems revealed that G. diffusa ray florets develop (and probably also initiate) basipetally, in the opposite direction to the disc florets-a developmental phenomenon that has been found in some other daisies, but which contradicts conventional theories of daisy inflorescence architecture. Using these ontogenetic and morphological data, we have identified the mechanism by which G. diffusa patterns its insect-mimicking petal spots, and we propose a testable model for the genetic regulation of petal spot identity. PMID:21622334

  16. Development of HTS Magnet for Rotating Gantry

    NASA Astrophysics Data System (ADS)

    Tasaki, Kenji; Koyanagi, Kei; Takayama, S. Shigeki; Ishii, Yusuke; Kurusu, Tsutomu; Amemiya, Naoyuki; Ogitsu, Toru; iwata, Yoshiyuki; Noda, Koji

    The effectiveness of heavy-ion radiotherapy for cancer treatment has been recognized by medical experts and the public. However, due to the large size of the equipment, this therapy has not been widely adopted. In particular, the rotating gantries used to irradiate patients with the heavy-ion beams from any direction may be as heavy as 600 tons in our estimation. By employing high-temperature superconducting (HTS) wires in these rotating gantries and increasing the magnetic field generated by the deflecting coils, the total weight of the rotating gantry can be reduced to around the weight of those used for proton radiotherapy. A project for developing an HTS deflecting magnet for heavy-ion radiotherapy has been underway since 2013, supported by the Japanese Ministry of Economy, Trade and Industry (METI) and the Japan Agency for Medical Research and Development (AMED). The aim of this project is to develop fundamental technologies for designing and fabricating HTS deflecting magnets, such as irregular magnetic field estimating techniques, design technology for HTS magnets, high-precision HTS coil winding technology, AC loss estimating techniques, and thermal runaway estimating techniques and to fabricate a small model of an HTS deflecting magnet and evaluate its performance. In this paper, the project's progress will be described.

  17. Postmortem Attraction of Sarcosaprophagous Diptera to Tramadol-Treated Rats and Morphometric Aspects of the Developed Larvae.

    PubMed

    AbouZied, E M

    2016-06-01

    The presence of some specific drugs in animal tissues may affect the time of minimal postmortem intervals estimated during forensic entomological investigations. To test the effects of a specific drug on decomposition, a field study was conducted at Fayoum University campus, Egypt, from March to May 2013, using tramadol, a synthetic analgesic opioid used to treat moderate to severe pain in humans. Albino rats were used as the animal model during this study. The duration of the fresh stage of tramadol treated rat (Ttr) carcasses was significantly shorter (2.4 ± 0.27 days) compared to tramadol free rat (Tfr) carcasses (6.4 ± 0.49 days). The dry carcass stage of Ttr lasted longer (10.3 ± 0.99 days) as compared to (7.4 ± 0.18 days) the Tfr carcass. The decomposition process of the (Ttr) carcass was not significantly faster (24.9 ± 1.58 days) as compared to (Tfr) carcasses (29.5 ± 1.69). Lucilia cuprina (Wiedemann), Chrysomya albiceps (Wiedemann), and Musca domestica L. were less attracted to Ttr carcass-baited traps than traps with Tfr carcasses. However, females of Sarcophaga spp. showed a greater attraction to Ttr carcasses. Females of another sarcophagid fly, Wohlfahrtia spp. exhibited similar attraction tendencies to both types of trap baits. Larvae of S. argyrostoma (Robineau-Desvoidy) collected from Ttr carcasses developed to a significantly longer total body length (10.4 ± 0.04 mm) as compared to the average length of the larvae collected from Tfr carcasses (8.9 ± 0.34 mm). During days 9-13 after rat death, the relative lengths of larvae from Ttr carcasses were not significantly different from Tfr carcasses. Larvae fed on Ttr carcasses pupated 2 days later than the control larvae. PMID:26931613

  18. The Changing Attractiveness of European Higher Education in the Next Decade: Current Developments, Future Challenges and Major Policy Issues

    ERIC Educational Resources Information Center

    Kwiek, Marek

    2009-01-01

    This article focuses on the different senses of the attractiveness of European systems and institutions for students, academics, the labour market and the economy, drawing attention to emergent tensions between different university stakeholders. Universities not only need to be attractive to increasingly differentiated student populations, but…

  19. The Role of Sexually Explicit Material (SEM) in the Sexual Development of Black Young Same-Sex-Attracted Men

    PubMed Central

    Morgan, Anthony; Ogunbajo, Adedotun; Trent, Maria; Harper, Gary W.; Fortenberry, J. Dennis

    2015-01-01

    Sexually explicit material (SEM) (including Internet, video, and print) may play a key role in the lives of Black same-sex sexually active youth by providing the only information to learn about sexual development. There is limited school-and/or family-based sex education to serve as models for sexual behaviors for Black youth. We describe the role SEM plays in the sexual development of a sample of Black same-sex attracted (SSA) young adolescent men ages 15–19. Adolescents recruited from clinics, social networking sites, and through snowball sampling were invited to participate in a 90-min, semi-structured qualitative interview. Most participants described using SEM prior to their first same-sex sexual experience. Participants described using SEM primarily for sexual development, including learning about sexual organs and function, the mechanics of same-gender sex, and to negotiate one’s sexual identity. Secondary functions were to determine readiness for sex; to learn about sexual performance, including understanding sexual roles and responsibilities (e.g., “top” or “bottom”); to introduce sexual performance scripts; and to develop models for how sex should feel (e.g., pleasure and pain). Youth also described engaging in sexual behaviors (including condom non-use and/or swallowing ejaculate) that were modeled on SEM. Comprehensive sexuality education programs should be designed to address the unmet needs of young, Black SSA young men, with explicit focus on sexual roles and behaviors that may be inaccurately portrayed and/or involve sexual risk-taking (such as unprotected anal intercourse and swallowing ejaculate) in SEM. This work also calls for development of Internet-based HIV/STI prevention strategies targeting young Black SSA men who maybe accessing SEM. PMID:25677334

  20. The role of sexually explicit material in the sexual development of same-sex-attracted Black adolescent males.

    PubMed

    Arrington-Sanders, Renata; Harper, Gary W; Morgan, Anthony; Ogunbajo, Adedotun; Trent, Maria; Fortenberry, J Dennis

    2015-04-01

    Sexually explicit material (SEM) (including Internet, video, and print) may play a key role in the lives of Black same-sex sexually active youth by providing the only information to learn about sexual development. There is limited school- and/or family-based sex education to serve as models for sexual behaviors for Black youth. We describe the role SEM plays in the sexual development of a sample of Black same-sex attracted (SSA) young adolescent males ages 15-19. Adolescents recruited from clinics, social networking sites, and through snowball sampling were invited to participate in a 90-min, semi-structured qualitative interview. Most participants described using SEM prior to their first same-sex sexual experience. Participants described using SEM primarily for sexual development, including learning about sexual organs and function, the mechanics of same-gender sex, and to negotiate one's sexual identity. Secondary functions were to determine readiness for sex; to learn about sexual performance, including understanding sexual roles and responsibilities (e.g., "top" or "bottom"); to introduce sexual performance scripts; and to develop models for how sex should feel (e.g., pleasure and pain). Youth also described engaging in sexual behaviors (including condom non-use and/or swallowing ejaculate) that were modeled on SEM. Comprehensive sexuality education programs should be designed to address the unmet needs of young, Black SSA men, with explicit focus on sexual roles and behaviors that may be inaccurately portrayed and/or involve sexual risk-taking (such as unprotected anal intercourse and swallowing ejaculate) in SEM. This work also calls for development of Internet-based HIV/STI prevention strategies targeting young Black SSA men who may be accessing SEM. PMID:25677334

  1. Development of high magnetic field superconducting magnet technology and applications in China

    NASA Astrophysics Data System (ADS)

    Wang, Qiuliang; Dai, Yingming; Zhao, Baozhi; Song, Shouseng; Lei, Yuanzhong; Wang, Houseng; Ye, Bai; Hu, Xinning; Huang, Tianbing; Wang, Hui; He, Chu; Shang, Muxi; Wang, Chao; Cui, Chunyan; Zhao, Shangwu; Zhang, Quan; Diao, Yanhua; Peng, Yan; Xu, Guoxin; Deng, Fanping; Weng, Peide; Kuang, Guangli; Gao, Bingjun; Lin, Liangzhen; Yan, Luguang

    2007-07-01

    High magnetic field superconducting magnet technology has been developed in the recent years for all kinds of applications in China. The superconducting magnets on the basis of the conduction-cooled high (HTS) and lower temperature superconductor (LTS) through GM cryocooler are designed, fabricated and operated for the magnetic separator, superconducting magnet energy storage system (SMES), material processing, gyrotron, electromagnetic launcher, space anti-matter detection, magnetic surgery system (MSS), heavy ion accelerator dipole magnet and test bed for characteristics of superconducting material in Institute of Electrical Engineering, Chinese Academy of Sciences (IEECAS). The EAST superconducting Tokamak is being fabricated in Institute of Plasma Physics, Chinese Academy of Sciences. In the paper, we report the successful development of high magnetic field superconducting magnet technology in China. Some new research projects, such as 40 T hybrid magnet, 25 T high magnetic field superconducting magnet, split-pair magnets for the pallation Neutron Source, high temperature superconducting coils for MSS and MRI are introduced.

  2. Correlates of Interpersonal Attraction.

    ERIC Educational Resources Information Center

    Prisbell, Marshall

    A study assessed the relationship of the independent variables of interpersonal attraction to the dependent variables of feeling good, relational safety, and uncertainty level. Subjects were 75 elementary and secondary school teachers, 61 communication students, 18 child development professionals, and 8 service club members. Each subject completed…

  3. Attractive characteristics of mirrors

    NASA Astrophysics Data System (ADS)

    Post, R. F.; Ryutov, D. D.

    1994-12-01

    A summary of the attractive characteristics of mirror devices is presented. Recent progress in development of axisymmetric mirror devices is described. Potentialities of mirrors as a basis for D(3)He fusion power generators and high-flux neutron sources for fusion material tests are discussed.

  4. Translational Development Strategy for Magnetic Seizure Therapy

    PubMed Central

    Rowny, Stefan; Benzl, Karla; Lisanby, Sarah H.

    2009-01-01

    Electroconvulsive therapy (ECT) has unparalleled antidepressant efficacy, but its cognitive side effects may be persistent. Research suggests that the side effects may be at least partially dissociable from the therapeutic effects of ECT, suggesting that distinct cortical networks may underlie them and introducing a role for focal seizure induction as a means of minimizing side effects. In magnetic seizure therapy (MST), magnetic fields avoid tissue impedance and induce electrical currents confined to superficial cortex, facilitating focal seizure induction. The translational development strategy for MST has included: (1) device development, (2) feasibility in animals and initial human trials, (3) testing in nonhuman primates on safety and mechanisms of action (with neuroanatomical, neurophysiological and cognitive endpoints), (4) safety testing in patients, (5) initial efficacy testing in patients, (6) dosage optimization, and (7) randomized comparison with ECT. These stages have been iterative, with results of early clinical testing prompting device enhancements that were, in turn, tested in nonhuman primates prior to human trials. Safety testing was aided by development of a nonhuman primate model of human ECT, and the validation of a cognitive battery for the monkey that is sensitive to the range of effects of ECT on human memory. Human testing has been facilitated by the development of an international consortium of centers addressing various aspects of technique and dose/response relationships. Challenges facing MST are common to other device based therapies: characterizing dose/response relationships, optimizing efficacy, and developing efficient and reliable methods to induce lasting therapeutic change in the circuitry underlying depression. PMID:19348798

  5. Development of superconducting magnet systems for HIFExperiments

    SciTech Connect

    Sabbi, Gian Luca; Faltens, A.; Leitzke, A.; Seidl, P.; Lund, S.; Martovets ky, N.; Chiesa, L.; Gung, C.; Minervini, J.; Schultz, J.; Goodzeit, C.; Hwang, P.; Hinson, W.; Meinke, R.

    2004-07-27

    The U.S. Heavy Ion Fusion program is developing superconducting focusing quadrupoles for near-term experiments and future driver accelerators. Following the fabrication and testing of several models, a baseline quadrupole design was selected and further optimized. The first prototype of the optimized design achieved a conductor-limited gradient of 132 T/m in a 70 mm bore, with measured field harmonics within 10 parts in 10{sup 4}. In parallel, a compact focusing doublet was fabricated and tested using two of the first-generation quadrupoles. After assembly in the cryostat, both magnets reached their conductor-limited quench current. Further optimization steps are currently underway to improve the performance of the magnet system and reduce its cost. They include the fabrication and testing of a new prototype quadrupole with reduced field errors as well as improvements of the cryostat design for the focusing doublet. The prototype units will be installed in the HCX beamline at LBNL, to perform accelerator physics experiments and gain operational experience. Successful results in the present phase will make superconducting magnets a viable option for the next generation of integrated beam experiments.

  6. Magnet Schools. Recent Developments and Perspectives.

    ERIC Educational Resources Information Center

    Estes, Nolan, Ed.; And Others

    This two-part anthology of research summaries examines the potential of magnet schools to provide equal education and educational access for minority group children and reviews successful magnet programs. Part 1, "Magnet Schools, Desegregation, and Choice," contains the following chapters: (1) "Using Magnet Schools for Desegregation: Some…

  7. Development of instrumentation for magnetic nondestructive evaluation

    SciTech Connect

    Hariharan, S.

    1991-09-23

    The use of failure-prone components in critical applications has been traditionally governed by removing such components from service prior to the expiration of their predicted life expectancy. Such early retirement of materials does not guarantee that a particular sample will not fail in actual usage. The increasing cost of such life expectancy based operation and increased demand for improved reliability in industrial settings has necessitated an alternate form of quality control. Modern applications employ nondestructive evaluation (NDE), also known as nondestructive testing (NDT), as a means of monitoring the levels and growth of defects in a material throughout its operational life. This thesis describes the modifications made to existing instrumentation used for magnetic measurements at the Center for Nondestructive Evaluation at Iowa State University. Development of a new portable instrument is also given. An overview of the structure and operation of this instrumentation is presented. This thesis discusses the application of the magnetic hysteresis and Barkhausen measurement techniques, described in Sections 1.3.1 and 1.3.2 respectively, to a number of ferromagnetic specimens. Specifically, measurements were made on a number of railroad steel specimens for fatigue characterization, and on specimens of Damascus steel and Terfenol-D for materials evaluation. 60 refs., 51 figs., 5 tabs.

  8. Development of peristaltic crawling robot using magnetic fluid on the basis of locomotion mechanism of earthworm

    NASA Astrophysics Data System (ADS)

    Saga, Norihiko; Nakamura, Taro

    2002-11-01

    The field of bio-engineering with the aim of developing new machines, which utilizes the motion and control of organisms as a model, is attracting attention. This technology is pursued by paying attention to various shapes and movements of organisms and autonomous system of organisms in acting in response to environment surrounding them, and by mechanically elucidating the locomotion mechanism, propulsive mechanism, nerve system and sensation system of these organisms. On the other hand, in the field of hydrodynamics, magnetic fluid that changes its apparent viscosity depending on magnetic field has been developed, and its utilization is under trial in various fields. We paid attention to the peristaltic crawling of earthworm as transport function in place of wheels or ambulation, and have developed a micro robot running inside a tube using magnetic fluid. In this micro robot, a cell corresponding to earthworm's segment is composed of a natural rubber tube sealed with water-based magnetic fluid, and the cells are connected with elastic rods made of natural rubber. The feature of this micro robot is that its structure is simply composed of, and it can be controlled with external wireless force, by providing it with moving magnetism from the outside. This paper presents the analytical result of the peristaltic crawling of an actual earthworm and the evaluation result of transport mechanism of a prototype micro robot moved by external magnetic field.

  9. Developing Glassy Magnets from Simulated Composition of Martian Soil for Exploration Applications

    NASA Technical Reports Server (NTRS)

    Ramachandran, N.; Ray, C. S.; Rogers, J. R.

    2004-01-01

    The long-term exploration goals of NASA include developing human habitation on Mars and conducting scientific investigations on Mars and other planetary bodies. In situ resource processing is a key objective in this area. We focus on the possibility of making magnetic glasses in situ for potential applications development. The paper will focus on ongoing work at NASA Marshall Space Flight Center on making magnetic glass from Mars soil simulants and its characterization. Analysis of the glass morphology, strength, chemistry and resulting magnetic properties will provide a fundamental understanding of the synthesized material that can be used for potential applications development. in an effort to characterize the magnetic properties of the Mars glasses, a series of tests were performed at NASA MSFC. Preliminary tests indicated that the glasses were attracted to a magnet and also had a small amount of residual magnetism. They were opaque (almost black in color). As the first step, a sample of Mars 1 glass (approx.1 mm x 1 mm x 5 mm length) was machined, weighed and its hysteresis curve was measured using a Vibration Sample Magnetometer (VSM). Next, a small furnace was designed and built and the sample was baked in a graphite (reducing agent) crucible at 800 C in an Argon atmosphere for 3 hours in the presence of a uniform, transverse (transverse to the 5mm length of the sample) magnetic field of 0.37 Tesla. The treated sample showed reddening on the outside and showed substantially increased residual magnetism. This sample was again analyzed in the VSM. The data clearly showed that some chemical change occurred during the heat treatment (color change) and that both the glasses have useful magnetic properties. Although no orientation effects of the magnetic field were considered, the data showed the following: 1. Both glass samples are primarily soft magnets and display ferromagnetic behavior (hysteresis, saturation, etc.) 2. The treated glass has improved saturation

  10. Magnetic nanostructures: radioactive probes and recent developments

    NASA Astrophysics Data System (ADS)

    Prandolini, M. J.

    2006-05-01

    The miniaturization of magnetic sensors and storage devices down to the nano-scale leads to drastic changes in magnetic phenomena compared with the same devices with a larger size. Excited-nuclear-probe (radioactive probe) techniques are ideal for investigating these new magnetic nanostructures. By observing the magnetic hyperfine fields (and in some cases the electric-field-gradients (EFGs)) at the nuclei of radioactive probes, microscopic information about the magnetic environment of the probes is acquired. The magnetic hyperfine field is particularly sensitive to the s-spin polarization of the conduction electrons and to the orbital magnetic moment of the probe atom. Three methods of inserting radioactive probes into magnetic nanostructures are presented; neutron activation, recoil implantation and 'soft-landing', followed by descriptions of their application to selected examples. In some cases, these methods offer the simultaneous creation and observation of new magnetic materials at the atomic scale. This review focuses firstly on the induced magnetism in noble-metal spacer layers between either ferromagnetic (FM) or FM/antiferromagnetic (AFM) layers in a trilayer structure. Using the method of low-temperature nuclear orientation, the s-spin polarization of noble-metal probes was measured and was found to be very sensitive to the magnetic properties at both the FM and AFM interfaces. Secondly, the recoil implantation of radioactive Fe probes into rare-earth hosts and d-band alloys and subsequent measurement using time-differential perturbed angular distribution offer the possibility of controlling the chemical composition and number of nearest-neighbours. This method was used to prepare local 3d-magnetic clusters in a non-magnetic matrix and to observe their magnetic behaviour. Finally, non-magnetic radioactive probes were 'soft-landed' onto Ni surfaces and extremely lattice-expanded ultrathin Ni films. By measuring the magnetic hyperfine fields and EFGs at

  11. Development of a Thin Film Magnetic Moment Reference Material

    PubMed Central

    Pappas, D. P.; Halloran, S. T.; Owings, R. R.; da Silva, F. C. S.

    2008-01-01

    In this paper we present the development of a magnetic moment reference material for low moment magnetic samples. We first conducted an inter-laboratory comparison to determine the most useful sample dimensions and magnetic properties for common instruments such as vibrating sample magnetometers (VSM), SQUIDs, and alternating gradient field magnetometers. The samples were fabricated and then measured using a vibrating sample magnetometer. Their magnetic moments were calibrated by tracing back to the NIST YIG sphere, SRM 2853. PMID:27096108

  12. Development of a Thin Film Magnetic Moment Reference Material.

    PubMed

    Pappas, D P; Halloran, S T; Owings, R R; da Silva, F C S

    2008-01-01

    In this paper we present the development of a magnetic moment reference material for low moment magnetic samples. We first conducted an inter-laboratory comparison to determine the most useful sample dimensions and magnetic properties for common instruments such as vibrating sample magnetometers (VSM), SQUIDs, and alternating gradient field magnetometers. The samples were fabricated and then measured using a vibrating sample magnetometer. Their magnetic moments were calibrated by tracing back to the NIST YIG sphere, SRM 2853. PMID:27096108

  13. Attractiveness and School Achievement

    ERIC Educational Resources Information Center

    Salvia, John; And Others

    1977-01-01

    The purpose of this study was to ascertain the relationship between rated attractiveness and two measures of school performance. Attractive children received significantly higher report cards and, to some degree, higher achievement test scores than their unattractive peers. (Author)

  14. Development of magnetic separation system of magnetoliposomes

    NASA Astrophysics Data System (ADS)

    Nakao, R.; Matuo, Y.; Mishima, F.; Taguchi, T.; Maenosono, S.; Nishijima, S.

    2009-10-01

    The magnetic separation technology using sub-microsized ferromagnetic particle is indispensable in many areas of medical biosciences. For example, ferromagnetic particles (200-500 nm) are widely used for cell sorting in stem cell research with the use of cell surface-specific antigens. Nanosized ferromagnetic particles (10-20 nm) have been suggested as more suitable in drug delivery studies given their efficiency of tissue penetration, however, the magnetic separation method for them has not been established. One of the major reasons is that magnetic force acting on the object particles decreases drastically as a particle diameter becomes small. In this study, magnetic force acting on the targets was enhanced by the combination of superconducting magnet and the filter consisting of ferromagnetic particle. By doing so, we confirmed that Fe 3O 4 of 20 nm in diameter was trapped in the magnetic filter under an external magnetic field of 0.5 T. Fe 3O 4 encapsulated with phospholipid liposomes of 200 nm in diameter was also shown to be trapped as external magnetic field of 1.5 T, but not of 0.5 T. We also showed the result of particle trajectory calculation which emulated well the experimental data.

  15. Novel magnetic tips developed for the switching magnetization magnetic force microscopy.

    SciTech Connect

    Cambel, V.; Elias, P.; Gregusova, D.; Fedor, J.; Martaus, J.; Karapetrov, G.; Novosad, V.; Kostic, I.; Materials Science Division; Slovak Academy of Sciences

    2010-07-01

    Using micromagnetic calculations we search for optimal magnetic properties of novel magnetic tips to be used for a Switching Magnetization Magnetic Force Microscopy (SM-MFM), a novel technique based on two-pass scanning with reversed tip magnetization. Within the technique the sum of two scans images local atomic forces and their difference maps the local magnetic forces. The tip magnetization is switched during the scanning by a small magnetic field. The technology of novel low-coercitive magnetic tips is proposed. For best performance the tips must exhibit low magnetic moment, low switching field, and single-domain state at remanence. Such tips are equipped with Permalloy objects of a precise shape that are defined on their tilted sides. We calculate switching fields of such tips by solving the micromagnetic problem to find the optimum shape and dimensions of the Permalloy objects located on the tips. Among them, hexagon was found as the best shape for the tips.

  16. On the rheology of pendular gels and morphological developments in paste-like ternary systems based on capillary attraction.

    PubMed

    Domenech, Trystan; Velankar, Sachin S

    2015-02-28

    We investigate capillary bridging-induced gelation phenomena in silica particle suspensions and pastes, where a particle-wetting fluid is added as the third component. Increasing the wetting fluid loading in the ternary system induces a morphological transition from a pendular network to compact capillary aggregates network, with an intermediate funicular state. To our knowledge, the formation of percolated structures from compact capillary aggregates when the volume fraction of a wetting fluid approaches that of the particles is unprecedented. Such structures appear to result from the arrested coalescence of compact capillary aggregates due to the balance between the Laplace pressure and solid-like properties (yield stress, elasticity) of the aggregates. Shear-induced yielding of the ternary systems, linked to their percolating nature, is strongly influenced by the amount of wetting fluid phase. A non-monotonic dependence of the yield stress on the amount of wetting fluid is found, with the maximum yield stress obtained for a wetting fluid-to-particle volume fraction ratio of 0.2-0.3. For pendular systems, linear viscoelastic properties display a soft glassy rheological behavior above the percolation threshold (around 4 vol% particles), and complex viscosity data can be scaled using the high frequency plateau value, as well as a single characteristic relaxation time, which decreases when the particle concentration is increased. In addition, the particle concentration dependence of the yielding transition in the pendular regime appears to be efficiently described by two parameters extracted from the steady state flow curves: the yield stress and the limiting viscosity at a high shear rate. Although these non-colloidal networks result from flow-driven assembly, the scaling laws for our pendular gels are reminiscent of colloidal gels with a fractal geometry. Our studies pinpoint new pathways to create physical gels where the interparticle attraction strength is

  17. Development of Interior Permanent Magnet Motors with Concentrated Windings for Reducing Magnet Eddy Current Loss

    NASA Astrophysics Data System (ADS)

    Yamazaki, Katsumi; Kanou, Yuji; Fukushima, Yu; Ohki, Shunji; Nezu, Akira; Ikemi, Takeshi; Mizokami, Ryoichi

    In this paper, we present the development of interior magnet motors with concentrated windings, which reduce the eddy current loss of the magnets. First, the mechanism of the magnet eddy current loss generation is investigated by a simple linear magnetic circuit. Due to the consideration, an automatic optimization method using an adaptive finite element method is carried out to determine the stator and rotor shapes, which decrease the eddy current loss of the magnet. The determined stator and rotor are manufactured in order to proof the effectiveness by the measurement.

  18. Development of Modeling and Simulation for Magnetic Particle Inspection Using Finite Elements

    SciTech Connect

    Jun-Youl Lee

    2003-05-31

    Magnetic particle inspection (MPI) is a widely used nondestructive inspection method for aerospace applications essentially limited to experiment-based approaches. The analysis of MPI characteristics that affect sensitivity and reliability contributes not only reductions in inspection design cost and time but also improvement of analysis of experimental data. Magnetic particles are easily attracted toward a high magnetic field gradient. Selection of a magnetic field source, which produces a magnetic field gradient large enough to detect a defect in a test sample or component, is an important factor in magnetic particle inspection. In this work a finite element method (FEM) has been employed for numerical calculation of the MPI simulation technique. The FEM method is known to be suitable for complicated geometries such as defects in samples. This thesis describes the research that is aimed at providing a quantitative scientific basis for magnetic particle inspection. A new FEM solver for MPI simulation has been developed in this research for not only nonlinear reversible permeability materials but also irreversible hysteresis materials that are described by the Jiles-Atherton model. The material is assumed to have isotropic ferromagnetic properties in this research (i.e., the magnetic properties of the material are identical in all directions in a single crystal). In the research, with a direct current field mode, an MPI situation has been simulated to measure the estimated volume of magnetic particles around defect sites before and after removing any external current fields. Currently, this new MPI simulation package is limited to solving problems with the single current source from either a solenoid or an axial directional current rod.

  19. Magnetic refrigeration: recent developments and alternative configurations

    NASA Astrophysics Data System (ADS)

    Almanza, Morgan; Kedous-Lebouc, Afef; Yonnet, Jean-Paul; Legait, Ulrich; Roudaut, Julien

    2015-07-01

    Magnetic refrigeration, based on magnetocaloric effect, is an upcoming environmentaly friendly technology with a high potential to improve energy efficiency and to reduce greenhouse gas emission. It is a multidisciplinary research theme and its real emergence requires, to overcome scientific and technical issues related to both material and system. This paper presents the state of the art in magnetic cooling, the main recent works achieved and discusses in more details the thermodynamic phenomenon according to the G2Elab experience in the field. Contribution to the topical issue "Electrical Engineering Symposium (SGE 2014)", edited by Adel Razek

  20. Developing Glassy Magnets from Simulated Composition of Martian Soil for Exploration Applications

    NASA Technical Reports Server (NTRS)

    Ramachandran, Narayanan; Ray, Chandra; Rogers, Jan

    2004-01-01

    The long-term exploration goals of NASA include developing human habitation on Mars and conducting scientific investigations on Mars and other planetary bodies. In situ resource processing is a key objective in this area We focus OR the possibility of making magnetic glasses in situ for potential applications development. The paper will focus on ongoing work at NASA Marshall Space Flight Center on making magnetic glass h m Mars soil simulants and its characterization. Analysis of the glass morphology, strength, chemistry and resulting magnetic properties will provide a fi.mdamenta1 understanding ofthe synthesized materiai that can be used for pomtiai appiications cieveiopment. In an effort to characterize the magnetic properbes of the Mars glasses, a series of tests were performed at NASA MSFC. Preliminary tests indicated that the glasses were attracted to a magnet and also had a small amount of residual magnetism. They were opaque (almost black in color). As the first step, a sample of Mars 1 glass (-lm x lmm x 5 mm length) was machined, weighed and its hysteresis curve was measured using a Vibration Sample Magnetometer 0. Next, a small furnace was designed and built and the sample was baked in a graphite (reducing agent) crucible at 800 C in an Argon atmosphere for 3 hours in the presence of a uniform, transverse (transverse to the 5mm length of the sample) magnetic field of 0.37 Tesla. The treated sample showed reddening on the outside and showed substantially increased residual magnetism. This sample was again analyzed in the VSM. The data clearly showed that some chemical change occurred during the heat treatment (color change) and that both the glasses have useful magnetic properties. Although no orientation effects of the magnetic field were considered, the data showed the following: 1. Both glass samples are primarily soft magnets and display ferromagnetic behavior (hysteresis, saturation, etc.) 2. The treated glass has improved saturation magnetism (order

  1. Comparative Analysis of Local Planning and Development of Magnet Schools.

    ERIC Educational Resources Information Center

    Blank, Rolf K.

    This paper, based on a recent comparative study of magnet schools conducted by the Department of Education, describes the features of successfully designed magnet schools. First, the paper highlights some of the major findings from the study on which it is based. Although there is a wide degree of variation in the design, development, and…

  2. Career Development Effects of Career Magnets versus Comprehensive Schools.

    ERIC Educational Resources Information Center

    Flaxman, Erwin; Guerrero, Anabelle; Gretchen, Denise

    The effects of attending an urban career magnet high school were examined by comparing the career development of 51 graduates of 4 career magnet high schools and 59 graduates of 4 comprehensive high schools in a large city. Subjects were drawn from a database through a random assignment and matching process. All 110 graduates were surveyed using…

  3. Development of a boundary magnetic charge method for computing magnetic fields in a system containing saturated magnetic materials

    NASA Astrophysics Data System (ADS)

    Murata, H.; Ishigami, M.; Shimoyama, H.

    2016-01-01

    In previous research, we developed a three-dimensional (3D) boundary magnetic charge method (BMCM) for high-accuracy field calculations in a static magnetic field, even when there exist great differences between the magnitudes of permeability between neighboring magnetic materials. This method, however, cannot be applied to a system that contains saturated magnetic materials. In the present study, therefore, we have developed a novel method that addresses this issue. According to this new method, we divide the region containing the magnetic material into small-volume elements and divide the boundaries between neighboring small-volume elements into small-surface elements, assigning each element an appropriate initial value of permeability. The magnetic field inside and outside of the magnetic material is calculated using this permeability. The value of the permeability of each element is iteratively updated using μ-H data. The updated value of the permeability after the i-th iteration, μi, is compared with that of the previous value, μi-1. If the difference between the two values is within a preset range, the iteration process is judged to have converged and the value of μi is regarded as the final converged value of the permeability. The magnetic field at an arbitrary point in space and/or inside the body of the magnetic material is calculated from the converged permeability of each element. As a result, we have succeeded in developing a novel BMCM for the calculation of a static magnetic field with high accuracy in a system containing saturated magnetic materials.

  4. Assertiveness and Physical Attractiveness.

    ERIC Educational Resources Information Center

    Kleim, David M.; And Others

    Earlier research investigating the relationship between physical attractiveness and assertiveness found that physically attractive females were more assertive than other females. To investigate this relationship further and to broaden the scope of the study, 69 students were videotaped in groups of five to ten while responding to open-ended…

  5. Intelligence and Physical Attractiveness

    ERIC Educational Resources Information Center

    Kanazawa, Satoshi

    2011-01-01

    This brief research note aims to estimate the magnitude of the association between general intelligence and physical attractiveness with large nationally representative samples from two nations. In the United Kingdom, attractive children are more intelligent by 12.4 IQ points (r=0.381), whereas in the United States, the correlation between…

  6. Development of a compact superconducting magnet with a GdBCO magnetic lens

    NASA Astrophysics Data System (ADS)

    Zhang, Z. Y.; Matsumoto, S.; Teranishi, R.; Kiyoshi, T.

    2013-10-01

    Concentration of a magnetic field has been achieved using a Gd-Ba-Cu-O (GdBCO) magnetic lens. A conduction-cooled compact high-field superconducting magnet with a GdBCO magnetic lens was developed. The magnet possessed a 10-mm room-temperature bore and consisted of two Nb-Ti solenoid coils and a GdBCO magnetic lens, which was installed at the center of the Nb-Ti coils in order to concentrate the background field generated by the Nb-Ti coils. The Nb-Ti coils and the GdBCO magnetic lens were cooled using a two-stage pulse-tube cryocooler. A concentrated magnetic field of 10.3 T was obtained at a background field of 5.6 T provided by the Nb-Ti coils. No degradation was found in the magnet during repeat excitation. The large field gradient generated by the GdBCO magnetic lens is expected to be used for the levitation of diamagnetic materials.

  7. Development of Small-sized Fluid Control Valve with Self-holding Function Using Permanent Magnet

    NASA Astrophysics Data System (ADS)

    Akagi, Tetsuya; Dohta, Shujiro; Ueda, Hirofumi

    Recently, force feedback devices in virtual reality and power assisted nursing care systems have received much attention and active research. In such a control system, an actuator and a driving device such as a control valve are mounted on the human body. In this condition, the size and weight of the control valve become serious problems. At the same time, the valve should be operated with lower energy consumption because of using a limited electrical power. The typical electro magnetic solenoid valve drives its spool using a larger solenoid to open the valve. The complex construction of the valve for sealing makes its miniaturization and the fabrication of a low cost valve more difficult. In addition, the solenoid in the valve consumes more electrical power while the valve is kept opening. The purpose of our study is to develop a small-sized, lightweight, lower energy consumption and flexible control valve that can be safe enough to mount on the human body at a lower cost. In our pervious study, we proposed and tested the control valve that can open using a vibration motor. In this study, we propose and test a new type of fluid control valve with a self-holding function. The new valve uses a permanent magnet ball. It has a cylindrical magnet and two solenoids. The self-holding function of the valve is done as follows. When one side of the solenoid is stimulated by the current momentarily, the solenoid gives a repulsive force to the cylindrical magnet. The magnet moves toward the opposite side of the solenoid and is attracted to the iron core. Then, the magnet ball moves toward the cylindrical magnet and opens the orifice. The valve can keep open without electrical energy. As a result, the valve with the extremely lower energy consumption can be developed.

  8. Space Magnets Attracting Interest on Earth: Applications of Physical and Biological Techniques In the Study of Gravisensing and Response System of Plants

    NASA Technical Reports Server (NTRS)

    Hasenstein, Karl H.; Boody, April; Cox, David (Technical Monitor)

    2002-01-01

    The BioTube/Magnetic Field Apparatus (MFA) research is designed to provide insight into the organization and operation of the gravity sensing systems of plants and other small organisms. This experiment on STS-107 uses magnetic fields to manipulate sensory cells in plant roots, thus using magnetic fields as a tool to study gravity-related phenomena. The experiment will be located in the SPACEHAB module and is about the size of a household microwave oven. The goal of the experiment is to improve our understanding of the basic phenomenon of how plants respond to gravity. The BioTube/MFA experiment specifically examines how gravitational forces serve as a directional signal for growth in the low-gravity environment of space. As with all basic research, this study will contribute to an improved understanding of how plants grow and will have important implications for improving plant growth and productivity on Earth. In BioTube/MFA, magnetic fields will be used to determine whether the distribution of subcellular starch grains, called amyloplasts, within plant cells predicts the direction in which roots will grow and curve in microgravity.

  9. Development and Testing of an Axial Halbach Magnetic Bearing

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.; Gallo, Christopher A.; Thompson, William K.

    2006-01-01

    The NASA Glenn Research Center has developed and tested a revolutionary Axial Halbach Magnetic Bearing. The objective of this work is to develop a viable non-contact magnetic thrust bearing utilizing Halbach arrays for all-electric flight, and many other applications. This concept will help to reduce harmful emissions, reduce the Nation s dependence on fossil fuels and mitigate many of the concerns and limitations encountered in conventional axial bearings such as bearing wear, leaks, seals and friction loss. The Axial Halbach Magnetic Bearing is inherently stable and requires no active feedback control system or superconductivity as required in many magnetic bearing designs. The Axial Halbach Magnetic Bearing is useful for very high speed applications including turbines, instrumentation, medical systems, computer memory systems, and space power systems such as flywheels. Magnetic fields suspend and support a rotor assembly within a stator. Advanced technologies developed for particle accelerators, and currently under development for maglev trains and rocket launchers, served as the basis for this application. Experimental hardware was successfully designed and developed to validate the basic principles and analyses. The report concludes that the implementation of Axial Halbach Magnetic Bearings can provide significant improvements in rotational system performance and reliability.

  10. Development and Testing of a Radial Halbach Magnetic Bearing

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.; Gallo, Christopher A.; Thompson, William K.

    2006-01-01

    The NASA John H. Glenn Research Center has developed and tested a revolutionary Radial Halbach Magnetic Bearing. The objective of this work is to develop a viable non-contact magnetic bearing utilizing Halbach arrays for all-electric flight, and many other applications. This concept will help reduce harmful emissions, reduce the Nation s dependence on fossil fuels and mitigate many of the concerns and limitations encountered in conventional axial bearings such as bearing wear, leaks, seals and friction loss. The Radial Halbach Magnetic Bearing is inherently stable and requires no active feedback control system or superconductivity as required in many magnetic bearing designs. The Radial Halbach Magnetic Bearing is useful for very high speed applications including turbines, instrumentation, medical applications, manufacturing equipment, and space power systems such as flywheels. Magnetic fields suspend and support a rotor assembly within a stator. Advanced technologies developed for particle accelerators, and currently under development for maglev trains and rocket launchers, served as the basis for this application. Experimental hardware was successfully designed and developed to validate the basic principles and analyses. The report concludes that the implementation of Radial Halbach Magnetic Bearings can provide significant improvements in rotational system performance and reliability.

  11. Status of high temperature superconductor development for accelerator magnets

    NASA Technical Reports Server (NTRS)

    Hirabayashi, H.

    1995-01-01

    High temperature superconductors are still under development for various applications. As far as conductors for magnets are concerned, the development has just been started. Small coils wound by silver sheathed Bi-2212 and Bi-2223 oxide conductors have been reported by a few authors. Essential properties of high T(sub c) superconductors like pinning force, coherent length, intergrain coupling, weak link, thermal property, AC loss and mechanical strength are still not sufficiently understandable. In this talk, a review is given with comparison between the present achievement and the final requirement for high T(sub c) superconductors, which could be particularly used in accelerator magnets. Discussions on how to develop high T(sub c) superconductors for accelerator magnets are included with key parameters of essential properties. A proposal of how to make a prototype accelerator magnet with high T(sub c) superconductors with prospect for future development is also given.

  12. Developments in boron magnetic resonance imaging (MRI)

    SciTech Connect

    Schweizer, M.

    1995-11-01

    This report summarizes progress during the past year on maturing Boron-11 magnetic resonance imaging (MRI) methodology for noninvasive determination of BNCT agents (BSH) spatially in time. Three major areas are excerpted: (1) Boron-11 MRI of BSH distributions in a canine intracranial tumor model and the first human glioblastoma patient, (2) whole body Boron-11 MRI of BSH pharmacokinetics in a rat flank tumor model, and (3) penetration of gadolinium salts through the BBB as a function of tumor growth in the canine brain.

  13. Development of reliable 70 T pulsed magnets

    NASA Astrophysics Data System (ADS)

    Lagutin, A.; Rosseel, K.; Herlach, F.; Vanacken, J.; Bruynseraede, Y.

    2003-12-01

    A capacitor-driven pulsed magnet coil has been designed to generate fields in the 70-75 T range, with a life expectancy of at least 100 pulses, thus qualifying as a '75 T class user magnet'. The bore is 10 mm and the rise time used in our experiments is 4 ms. The coil consists of two coaxial sections: the inner section, where stresses are highest, is made with CuNb microcomposite wire and optimized Zylon reinforcement; the outer section is made with soft copper and glass fibre composite. In the inner section, the stress in each layer is self-contained, while the stresses induced in the outer section are transmitted to a thick shell made from steel and carbon fibre composite. The cross section of the copper wires is adjusted to redistribute the heating evenly between the inner and the outer section. Another innovative design feature is a system for axial compression that can be easily retightened during coil training. Two nearly identical coils were manufactured and tested to 72 T this is a limit imposed due to overheating when using our 10 kV, 0.5 MJ capacitor bank (at an energy of 380 kJ). At 75 T, the calculated von Mises stress in the Zylon composite is 2.6 GPa, well below the UTS of more than 3 GPa, and the CuNb wire is still in an elastic state.

  14. Heritability of Attractiveness to Mosquitoes

    PubMed Central

    Fernández-Grandon, G. Mandela; Gezan, Salvador A.; Armour, John A. L.; Pickett, John A.; Logan, James G.

    2015-01-01

    Female mosquitoes display preferences for certain individuals over others, which is determined by differences in volatile chemicals produced by the human body and detected by mosquitoes. Body odour can be controlled genetically but the existence of a genetic basis for differential attraction to insects has never been formally demonstrated. This study investigated heritability of attractiveness to mosquitoes by evaluating the response of Aedes aegypti (=Stegomyia aegypti) mosquitoes to odours from the hands of identical and non-identical twins in a dual-choice assay. Volatiles from individuals in an identical twin pair showed a high correlation in attractiveness to mosquitoes, while non-identical twin pairs showed a significantly lower correlation. Overall, there was a strong narrow-sense heritability of 0.62 (SE 0.124) for relative attraction and 0.67 (0.354) for flight activity based on the average of ten measurements. The results demonstrate an underlying genetic component detectable by mosquitoes through olfaction. Understanding the genetic basis for attractiveness could create a more informed approach to repellent development. PMID:25901606

  15. Heritability of attractiveness to mosquitoes.

    PubMed

    Fernández-Grandon, G Mandela; Gezan, Salvador A; Armour, John A L; Pickett, John A; Logan, James G

    2015-01-01

    Female mosquitoes display preferences for certain individuals over others, which is determined by differences in volatile chemicals produced by the human body and detected by mosquitoes. Body odour can be controlled genetically but the existence of a genetic basis for differential attraction to insects has never been formally demonstrated. This study investigated heritability of attractiveness to mosquitoes by evaluating the response of Aedes aegypti (=Stegomyia aegypti) mosquitoes to odours from the hands of identical and non-identical twins in a dual-choice assay. Volatiles from individuals in an identical twin pair showed a high correlation in attractiveness to mosquitoes, while non-identical twin pairs showed a significantly lower correlation. Overall, there was a strong narrow-sense heritability of 0.62 (SE 0.124) for relative attraction and 0.67 (0.354) for flight activity based on the average of ten measurements. The results demonstrate an underlying genetic component detectable by mosquitoes through olfaction. Understanding the genetic basis for attractiveness could create a more informed approach to repellent development. PMID:25901606

  16. Attracting Water Drops

    NASA Video Gallery

    Astronauts Cady Coleman and Ron Garan perform the Attracting Water Drops experiment from Chabad Hebrew Academy in San Diego, Calif. This research determines if a free-floating water drop can be att...

  17. Adolescent attraction to cults.

    PubMed

    Hunter, E

    1998-01-01

    This article details the reasons behind adolescents' attraction to cults. It is recommended that parents, teachers, and counselors familiarize themselves with the warning signs. Suggestions are offered on how to make adolescents less vulnerable to cult overtures. PMID:9831888

  18. Attention Alters Perceived Attractiveness.

    PubMed

    Störmer, Viola S; Alvarez, George A

    2016-04-01

    Can attention alter the impression of a face? Previous studies showed that attention modulates the appearance of lower-level visual features. For instance, attention can make a simple stimulus appear to have higher contrast than it actually does. We tested whether attention can also alter the perception of a higher-order property-namely, facial attractiveness. We asked participants to judge the relative attractiveness of two faces after summoning their attention to one of the faces using a briefly presented visual cue. Across trials, participants judged the attended face to be more attractive than the same face when it was unattended. This effect was not due to decision or response biases, but rather was due to changes in perceptual processing of the faces. These results show that attention alters perceived facial attractiveness, and broadly demonstrate that attention can influence higher-level perception and may affect people's initial impressions of one another. PMID:26966228

  19. Physical Attractiveness and Courtship

    ERIC Educational Resources Information Center

    Silverman, Irwin

    1971-01-01

    This study shows a high and disquieting degree of similarity in physical attractiveness between dating partners, and suggests also that more similar partners tend to form stronger romantic attachments. (Author)

  20. Attracting Girls Into Physics

    NASA Astrophysics Data System (ADS)

    Hosny, Hala M.; Kahil, Heba M.

    2005-10-01

    From our national statistics, it is evident that in the population of physicists there are considerably fewer women than men. Our role is to attract girls to physics and thus decrease this gap. The institutional structure in Egypt provides an equal opportunity for girls to study sciences, including physics. It is reckoned that girls refrain from studying physics due to a group of social and economic factors. We will discuss teaching physics at schools and present some ideas to develop it. The media should play a role in placing female physicists in the spotlight. Unfortunately, careers that require intellectual skills are considered men's careers. This necessitates that society changes the way it sees women and trusts more in their skills and talents. We therefore call for the cooperation of governmental and nongovernmental bodies, together with universities and the production sectors involved. This will ultimately lead to enhancing the entrepreneurial projects related to physics and technology on the one hand, and will encourage girls to find challenging opportunities on the other.

  1. Extended use of superconducting magnets for bio-medical development

    SciTech Connect

    Stoynev, Stoyan E.

    2015-05-19

    Magnetic fields interact with biological cells affecting them in variety of ways which are usually hard to predict. Among them, it was observed that strong fields can align dividing cells in a preferred direction. It was also demonstrated that dividing cancer cells are effectively destroyed by applying electric fields in vivo with a success rate dependent on the cell-to-field orientation. Based on these facts, the present note aims to suggest the use of magnetic and electric fields for improved cancer treatment. Several possibilities of generating the electric fields inside the magnetic field volume are reviewed, main tentative approaches are described and discussed. Most if not all of them require special magnet configuration research which can be based on existing magnet systems in operation or in development.

  2. Development of fast cooling pulsed magnets at the Wuhan National High Magnetic Field Center

    SciTech Connect

    Peng, Tao; Sun, Quqin; Zhao, Jianlong; Jiang, Fan; Li, Liang; Xu, Qiang; Herlach, Fritz

    2013-12-15

    Pulsed magnets with fast cooling channels have been developed at the Wuhan National High Magnetic Field Center. Between the inner and outer sections of a coil wound with a continuous length of CuNb wire, G10 rods with cross section 4 mm × 5 mm were inserted as spacers around the entire circumference, parallel to the coil axis. The free space between adjacent rods is 6 mm. The liquid nitrogen flows freely in the channels between these rods, and in the direction perpendicular to the rods through grooves provided in the rods. For a typical 60 T pulsed magnetic field with pulse duration of 40 ms, the cooling time between subsequent pulses is reduced from 160 min to 35 min. Subsequently, the same technology was applied to a 50 T magnet with 300 ms pulse duration. The cooling time of this magnet was reduced from 480 min to 65 min.

  3. High Temperature, Permanent Magnet Biased, Fault Tolerant, Homopolar Magnetic Bearing Development

    NASA Technical Reports Server (NTRS)

    Palazzolo, Alan; Tucker, Randall; Kenny, Andrew; Kang, Kyung-Dae; Ghandi, Varun; Liu, Jinfang; Choi, Heeju; Provenza, Andrew

    2008-01-01

    This paper summarizes the development of a magnetic bearing designed to operate at 1,000 F. A novel feature of this high temperature magnetic bearing is its homopolar construction which incorporates state of the art high temperature, 1,000 F, permanent magnets. A second feature is its fault tolerance capability which provides the desired control forces with over one-half of the coils failed. The construction and design methodology of the bearing is outlined and test results are shown. The agreement between a 3D finite element, magnetic field based prediction for force is shown to be in good agreement with predictions at room and high temperature. A 5 axis test rig will be complete soon to provide a means to test the magnetic bearings at high temperature and speed.

  4. Discovery of mosquito attractants and attraction-inhibitors invited talk on attractants and repellents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The United States Department of Agriculture (USDA) has developed repellents and insecticides for the U.S. military since 1942. A small component of this research program has aimed at the discovery of attractants that can be used to produce potent lures for haematophagous arthropods, with a primary f...

  5. An Attractive Idea.

    ERIC Educational Resources Information Center

    Gentry, Evan; Hughes, Allan E.

    1986-01-01

    Describes electricity experiments which can be used for such purposes as determining the magnetic field of a magnet, making an electromagnet, and showing the repulsion of like poles of a magnet. Includes list of materials needed, procedures used, and instructional strategies. (JN)

  6. Influence of 60-Hz magnetic fields on sea urchin development

    SciTech Connect

    Zimmerman, S.; Zimmerman, A.M.; Winters, W.D.; Cameron, I.L. )

    1990-01-01

    Continuous exposure of sea urchin (Strongylocentrotus purpuratus) embryos at 18 degrees C to a cyclic 60-Hz magnetic field at 0.1 mT rms beginning 4 min after insemination caused a significant developmental delay during the subsequent 23 hours. No delay in development was recorded for periods up to 18 hours after fertilization. At 18 h, most embryos were in the mesenchyme blastula stage. At 23 h, most control embryos were in mid-gastrula whereas most magnetic-field-exposed embryos were in the early gastrula stage. Thus an estimated 1-h delay occurred between these developmental stages. The results are discussed in terms of possible magnetic-field modification of transcription as well as interference with cell migration during gastrulation. The present study extends and supports the growing body of information about potential effects of exposures to extremely-low-frequency (ELF) magnetic fields on developing organisms.

  7. Fault Tolerant Magnetic Bearing Testing and Conical Magnetic Bearing Development for Extreme Temperature Environments

    NASA Technical Reports Server (NTRS)

    Keith, Theo G., Jr.; Clark, Daniel

    2004-01-01

    During the six month tenure of the grant, activities included continued research of hydrostatic bearings as a viable backup-bearing solution for a magnetically levitated shaft system in extreme temperature environments (1000 F), developmental upgrades of the fault-tolerant magnetic bearing rig at the NASA Glenn Research Center, and assisting in the development of a conical magnetic bearing for extreme temperature environments, particularly turbomachinery. It leveraged work from the ongoing Smart Efficient Components (SEC) and the Turbine-Based Combined Cycle (TBCC) program at NASA Glenn Research Center. The effort was useful in providing technology for more efficient and powerful gas turbine engines.

  8. Development Of A Magnetic Directional-Solidification Furnace

    NASA Technical Reports Server (NTRS)

    Aldrich, Bill R.; Lehoczky, Sandor L.

    1996-01-01

    Report describes development of directional-solidification furnace in which axial magnetic field is imposed by surrounding ring permanent magnets and/or electromagnets and pole pieces. Furnace provides controlled axial temperature gradients in multiple zones, through which ampoule containing sample of material to be solidified is translated at controlled speed by low-vibration, lead-screw, stepping-motor-driven mechanism. Intended for use in low-gravity (spaceflight) experiments on melt growth of high-purity semiconductor crystals.

  9. High-field Magnet Development toward the High Luminosity LHC

    SciTech Connect

    Apollinari, Giorgio

    2014-07-01

    The upcoming Luminosity upgrade of the LHC (HL-LHC) will rely on the use of Accelerator Quality Nb3Sn Magnets which have been the focus of an intense R&D effort in the last decade. This contribution will describe the R&D and results of Nb3Sn Accelerator Quality High Field Magnets development efforts, with emphasis on the activities considered for the HL-LHC upgrades.

  10. MHD magnet technology development program summary, September 1982

    SciTech Connect

    Not Available

    1983-11-01

    The program of MHD magnet technology development conducted for the US Department of Energy by the Massachusetts Institute of Technology during the past five years is summarized. The general strategy is explained, the various parts of the program are described and the results are discussed. Subjects covered include component analysis, research and development aimed at improving the technology base, preparation of reference designs for commercial-scale magnets with associated design evaluations, manufacturability studies and cost estimations, the detail design and procurement of MHD test facility magnets involving transfer of technology to industry, investigations of accessory subsystem characteristics and magnet-flow-train interfacing considerations and the establishment of tentative recommendations for design standards, quality assurance procedures and safety procedures. A systematic approach (framework) developed to aid in the selection of the most suitable commercial-scale magnet designs is presented and the program status as of September 1982 is reported. Recommendations are made for future work needed to complete the design evaluation and selection process and to provide a sound technological base for the detail design and construction of commercial-scale MHD magnets. 85 references.

  11. Magnet and conductor developments for the Mirror Fusion Program

    SciTech Connect

    Cornish, D.N.

    1981-10-09

    The conductor development and the magnet design and construction for the MFTF are described. Future plans for the Mirror Program and their influence on the associated superconductor development program are discussed. Included is a summary of the progress being made to develop large, high-field, multifilamentary Nb/sub 3/Sn superconductors and the feasibility of building a 12-T yin-yang set of coils for the machine to follow MFTF. In a further look into the future, possible magnetic configurations and requirements for mirror reactors are surveyed.

  12. Attracting girls to physics

    NASA Astrophysics Data System (ADS)

    Borg, Anne; Sui, Manling

    2013-03-01

    Large regional differences remain in the number of girls studying physics and the number of female physicists in academic positions. While many countries struggle with attracting female students to university studies in physics, climbing the academic ladder is the main challenge for these women. Furthermore, for many female physicists the working climate is not very supportive. The workshop Attracting Girls to Physics, organized as part of the 4th IUPAP International Conference on Women in Physics, South Africa 2011, addressed attitudes among education-seeking teenagers and approaches for attracting young girls to physics through successful recruitment plans, including highlighting the broad spectrum of career opportunities for those with physics qualifications. The current paper presents findings, examples of best practices, and recommendations resulting from this workshop.

  13. Recent Developments in Magnetically Coupled Vane Pumps for Tritium Service

    SciTech Connect

    Capuder, F. C.; Quigley, L. T.; Baker, C. K.

    1985-04-01

    Despite advances in shaft sealing, a totally reliable shaft seal for two-stage vane pumps has never been developed. Therefore, the magnetically coupled vane pump drive was developed to solve the critical problem of tritium leakage at the shaft seals of vane pumps. As a result, radioactive contamination of the work area and loss of valuable material can now be prevented.

  14. Attracting Girls to Physics

    NASA Astrophysics Data System (ADS)

    Sandow, Barbara; Marks, Ann; Borg, Anne

    2009-04-01

    In most countries the number of girls studying physics, as well female physicists in academic positions, is still low. Active recruitment at all levels is essential to change this situation. In some countries a large proportion of students are female, but career progression is difficult. Highlighting the broad spectrum of career opportunities for those with physics qualifications is a major approach in attracting girls to physics. This paper presents findings, examples of best practices, and recommendations resulting from the workshop, Attracting Girls to Physics, organized as part of the Third IUPAP International Conference on Women in Physics, Seoul, 2008.

  15. Progress in development of high capacity magnetic HTS bearings

    NASA Astrophysics Data System (ADS)

    Kummeth, P.; Nick, W.; Neumueller, H.-W.

    2005-10-01

    HTS magnetic bearings are inherently stable without an active feedback system. They provide low frictional losses, no wear and allow operation at high rotational speed without lubrication. So they are very promising for use in motors, generators and turbines. We designed and constructed an HTS radial bearing for use with a 400 kW HTS motor. It consists of alternating axially magnetized permanent magnet rings on the rotor and a segmented YBCO stator. Stator cooling is performed by liquid nitrogen, the temperature of the stator can be adjusted by varying the pressure in the cryogenic vessel. At 68 K maximum radial forces of more than 3.7 kN were found. These results range within the highest radial bearing capacities reported worldwide. The encouraging results lead us to develop a large heavy load HTS radial bearing. Currently a high magnetic gradient HTS bearing for a 4 MVA synchronous HTS generator is under construction.

  16. Development of a 60 cm Magnetic Suspension System

    NASA Astrophysics Data System (ADS)

    Sawada, Hideo; Kunimasu, Tetsuya

    A 60cm Magnetic Suspension Balance System (MSBS), which has been developed in the National Aerospace Laboratory of Japan (NAL), is described in detail. Magnetic field in the MSBS is evaluated analytically and is compared with measured one. Available magnet kinds for the MSBS are selected analytically. The optimum ratio of diameter to length of cylindrical magnet for the MSBS is also evaluated. A model position sensing and the control systems are described with calibration test results. A model holding system is also shown, which is necessary for worker’s safety at suspending a large and massive model. The control system is presented and the measured model position during suspension is examined. The balance accuracy is examined and its error of drag force can be improved by restricting the calibration test to an expected drag range. Flow of the 60cm low-speed wind tunnel equipped with the MSBS is examined to be available for wind tunnel tests.

  17. U. S. developers join magnetic rail push

    SciTech Connect

    O'Connor, L.

    1993-08-01

    This article examines the state of development of maglev trains in the USA. The topics of the article include an overview of the various European and Japanese types, an all American concept, and overcoming competition. The article includes a sidebar on at test run of the Intercityexpress, a high-speed wheel-on-rail train along the northeast of the USA scheduled for fall of 1993.

  18. Development of a peristaltic crawling robot using magnetic fluid on the basis of the locomotion mechanism of the earthworm

    NASA Astrophysics Data System (ADS)

    Saga, Norihiko; Nakamura, Taro

    2004-06-01

    In the field of bio-engineering the aim of developing new machines which utilize the motion and control of organisms as a model is attracting attention. This technology is pursued by paying attention to various shapes and movements of organisms and autonomous system of organisms that act in response to the environment surrounding them, and by mechanically elucidating the locomotion mechanism, propulsive mechanism, nerve system and sensation system for these organisms. On the other hand, in the field of hydrodynamics, magnetic fluid that changes its apparent viscosity depending on the magnetic field has been developed, and its utilization is under trial in various fields. Attention has been paid to the peristaltic crawling of the earthworm as a transport function in place of wheels or ambulation, and based on these observations a micro-robot running inside a tube using magnetic fluid has been developed. In this micro-robot, individual cells corresponding to the earthworm's segment are composed of a natural rubber tube sealed with water-based magnetic fluid, and several cells are connected with elastic rods made of natural rubber. The feature of this micro-robot is that its structure is simply composed, and it can be controlled with external wireless force, by providing it with moving magnetism from the outside. This paper presents the analytical result on the peristaltic crawling of an actual earthworm and the evaluation result for the transport mechanism of a prototype micro-robot moved by an external magnetic field.

  19. The attracting power of the gaze of politicians is modulated by the personality and ideological attitude of their voters: a functional magnetic resonance imaging study.

    PubMed

    Cazzato, Valentina; Liuzza, Marco Tullio; Caprara, Gian Vittorio; Macaluso, Emiliano; Aglioti, Salvatore Maria

    2015-10-01

    Observing someone rapidly moving their eyes induces reflexive shifts of overt and covert attention in the onlooker. Previous studies have shown that this process can be modulated by the onlooker's personality, as well as by the social features of the person depicted in the cued face. Here, we investigated whether an individual's preference for social dominance orientation, in-group perceived similarity (PS), and political affiliation of the cued-face modulated neural activity within specific nodes of the social attention network. During functional magnetic resonance imaging, participants were requested to perform a gaze-following task to investigate whether the directional gaze of various Italian political personages might influence the oculomotor behaviour of in-group or out-group voters. After scanning, we acquired measures of PS in personality traits with each political personage and preference for social dominance orientation. Behavioural data showed that higher gaze interference for in-group than out-group political personages was predicted by a higher preference for social hierarchy. Higher blood oxygenation level-dependent activity in incongruent vs. congruent conditions was found in areas associated with orienting to socially salient events and monitoring response conflict, namely the left frontal eye field, right supramarginal gyrus, mid-cingulate cortex and left anterior insula. Interestingly, higher ratings of PS with the in-group and less preference for social hierarchy predicted increased activity in the left frontal eye field during distracting gaze movements of in-group as compared with out-group political personages. Our results suggest that neural activity in the social orienting circuit is modulated by higher-order social dimensions, such as in-group PS and individual differences in ideological attitudes. PMID:26262561

  20. Adolescent Attraction to Cults.

    ERIC Educational Resources Information Center

    Hunter, Eagan

    1998-01-01

    Details the reasons behind adolescents' attraction to cults. and distinguishes functions of cults and the term "cult." Identifies various cults, and describes the process of involvement. Notes that in the absence of authentic, stabilizing standards, some youth are especially vulnerable. Provides recommendations for adults working with adolescents.…

  1. Development of magnetically levitated high speed transport system in Japan

    SciTech Connect

    Sawada, Kazuo

    1996-07-01

    In Japan, huge passenger traffic moves through the Tokyo-Osaka corridor and the demand is mounting on one more high speed line besides the Tokaido Shinkansen. A magnetically levitated vehicle (JR Maglev) using superconducting magnets has been developed for the Tokyo-Osaka superspeed express. JR Maglev has many advantages over conventional rail systems. This paper describes the necessity of one more high speed line in this corridor, the reason the author chose Maglev, the scheme of this system, history of the development and outline of the new Yamanashi test line project.

  2. Development of magnetic resonance technology for noninvasive boron quantification

    SciTech Connect

    Bradshaw, K.M.

    1990-11-01

    Boron magnetic resonance imaging (MRI) and spectroscopy (MRS) were developed in support of the noninvasive boron quantification task of the Idaho National Engineering Laboratory (INEL) Power Burst Facility/Boron Neutron Capture Therapy (PBF/BNCT) program. The hardware and software described in this report are modifications specific to a GE Signa{trademark} MRI system, release 3.X and are necessary for boron magnetic resonance operation. The technology developed in this task has been applied to obtaining animal pharmacokinetic data of boron compounds (drug time response) and the in-vivo localization of boron in animal tissue noninvasively. 9 refs., 21 figs.

  3. Development of a superconducting bulk magnet for NMR and MRI

    NASA Astrophysics Data System (ADS)

    Nakamura, Takashi; Tamada, Daiki; Yanagi, Yousuke; Itoh, Yoshitaka; Nemoto, Takahiro; Utumi, Hiroaki; Kose, Katsumi

    2015-10-01

    A superconducting bulk magnet composed of six vertically stacked annular single-domain c-axis-oriented Eu-Ba-Cu-O crystals was energized to 4.74 T using a conventional superconducting magnet for high-resolution NMR spectroscopy. Shim coils, gradient coils, and radio frequency coils for high resolution NMR and MRI were installed in the 23 mm-diameter room-temperature bore of the bulk magnet. A 6.9 ppm peak-to-peak homogeneous region suitable for MRI was achieved in the central cylindrical region (6.2 mm diameter, 9.1 mm length) of the bulk magnet by using a single layer shim coil. A 21 Hz spectral resolution that can be used for high resolution NMR spectroscopy was obtained in the central cylindrical region (1.3 mm diameter, 4 mm length) of the bulk magnet by using a multichannel shim coil. A clear 3D MR image dataset of a chemically fixed mouse fetus with (50 μm)3 voxel resolution was obtained in 5.5 h. We therefore concluded that the cryogen-free superconducting bulk magnet developed in this study is useful for high-resolution desktop NMR, MRI and mobile NMR device.

  4. Development of a superconducting bulk magnet for NMR and MRI.

    PubMed

    Nakamura, Takashi; Tamada, Daiki; Yanagi, Yousuke; Itoh, Yoshitaka; Nemoto, Takahiro; Utumi, Hiroaki; Kose, Katsumi

    2015-10-01

    A superconducting bulk magnet composed of six vertically stacked annular single-domain c-axis-oriented Eu-Ba-Cu-O crystals was energized to 4.74 T using a conventional superconducting magnet for high-resolution NMR spectroscopy. Shim coils, gradient coils, and radio frequency coils for high resolution NMR and MRI were installed in the 23 mm-diameter room-temperature bore of the bulk magnet. A 6.9 ppm peak-to-peak homogeneous region suitable for MRI was achieved in the central cylindrical region (6.2 mm diameter, 9.1 mm length) of the bulk magnet by using a single layer shim coil. A 21 Hz spectral resolution that can be used for high resolution NMR spectroscopy was obtained in the central cylindrical region (1.3 mm diameter, 4 mm length) of the bulk magnet by using a multichannel shim coil. A clear 3D MR image dataset of a chemically fixed mouse fetus with (50 μm)(3) voxel resolution was obtained in 5.5 h. We therefore concluded that the cryogen-free superconducting bulk magnet developed in this study is useful for high-resolution desktop NMR, MRI and mobile NMR device. PMID:26295170

  5. Development of Halbach magnet for portable NMR device

    NASA Astrophysics Data System (ADS)

    Doğan, N.; Topkaya, R.; Subaşi, H.; Yerli, Y.; Rameev, B.

    2009-03-01

    Nuclear magnetic resonance (NMR) has enormous potential for various applications in industry as the on-line or at-line test/control device of process environments. Advantage of NMR is its non-destructive nature, because it does not require the measurement probe to have a contact with the tested media. Despite of the recent progress in this direction, application of NMR in industry is still very limited. This is related to the technical and analytical complications of NMR as a method, and high cost of NMR analyzers available at the market. However in many applications, NMR is a very useful technique to test various products and to monitor quantitatively industrial processes. Fortunately usually there is no need in a high-field superconducting magnets to obtain the high-resolution spectra with the detailed information on chemical shifts and coupling-constant. NMR analyzers are designed to obtain the relaxation parameters by measuring the NMR spectra in the time domain rather than in frequency domain. Therefore it is possible to use small magnetic field (and low frequency of 2-60 MHz) in NMR systems, based on permanent magnet technology, which are specially designed for specific at-line and on-line process applications. In this work we present the permanent magnet system developed to use in the portative NMR devices. We discuss the experimental parameters of the designed Halbach magnet system and compare them with results of theoretical modelling.

  6. Development of high gradient magnetic separation system under dry condition

    NASA Astrophysics Data System (ADS)

    Nakai, Y.; Mishima, F.; Akiyama, Y.; Nishijima, S.

    2010-11-01

    The interfusion of impurities such as metallic wear debris has been a problem in the manufacturing process of foods, medicines, and industrial products. Gravity separation system and membrane separation system has been used widely for powder separation, however magnetic separation system is much efficient to separate magnetic particles. Magnetic separation system under wet process is used conventionally, however, it has some demerit such as necessity of drying treatment after separation and difficulty of running the system in the cold region and so on. Thus, magnetic separation under dry process is prospective as alternative method. In this paper, we developed high gradient magnetic separation system (HGMS) under dry process. In dry HGMS system, powder coagulation caused by particle interaction is considerable. Powder coagulation causes a blockage of magnetic filters and results in decrease of separation performance of dry HGMS system. In order to investigate the effect of powder coagulation on separation performance, we conducted experiments with two kinds of powdered materials whose cohesive properties are different.

  7. Development of Prototype HTS Components for Magnetic Suspension Applications

    NASA Technical Reports Server (NTRS)

    Haldar, P.; Hoehn, J., Jr.; Selvamanickam, V.; Farrell, R. A.; Balachandran, U.; Iyer, A. N.; Peterson, E.; Salazar, K.

    1996-01-01

    We have concentrated on developing prototype lengths of bismuth and thallium based silver sheathed superconductors by the powder-in-tube approach to fabricate high temperature superconducting (HTS) components for magnetic suspension applications. Long lengths of mono and multi filament tapes are presently being fabricated with critical current densities useful for maglev and many other applications. We have recently demonstrated the prototype manufacture of lengths exceeding 1 km of Bi-2223 multi filament conductor. Long lengths of thallium based multi-filament conductor have also been fabricated with practical levels of critical current density and improved field dependence behavior. Test coils and magnets have been built from these lengths and characterized over a range of temperatures and background fields to determine their performance. Work is in progress to develop, fabricate and test HTS windings that will be suitable for magnetic suspension, levitation and other electric power related applications.

  8. United States Research and Development effort on ITER magnet tasks

    DOE PAGESBeta

    Martovetsky, Nicolai N.; Reierson, Wayne T.

    2011-01-22

    This study presents the status of research and development (R&D) magnet tasks that are being performed in support of the U.S. ITER Project Office (USIPO) commitment to provide a central solenoid assembly and toroidal field conductor for the ITER machine to be constructed in Cadarache, France. The following development tasks are presented: winding development, inlets and outlets development, internal and bus joints development and testing, insulation development and qualification, vacuum-pressure impregnation, bus supports, and intermodule structure and materials characterization.

  9. Conical Magnetic Bearing Development and Magnetic Bearing Testing for Extreme Temperature Environments

    NASA Technical Reports Server (NTRS)

    Keith, Theo G., Jr.; Jansen, Mark

    2004-01-01

    The main proposed research of this grant were: to design a high-temperature, conical magnetic bearing facility, to test the high-temperature, radial magnetic bearing facility to higher speeds, to investigate different backup bearing designs and materials, to retrofit the high-temperature test facility with a magnetic thrust bearing, to evaluate test bearings at various conditions, and test several lubricants using a spiral orbit tribometer. A high-temperature, conical magnetic bearing facility has been fully developed using Solidworks. The facility can reuse many of the parts of the current high-temperature, radial magnetic bearing, helping to reduce overall build costs. The facility has the ability to measure bearing force capacity in the X, Y, and Z directions through a novel bearing mounting design. The high temperature coils and laminations, a main component of the facility, are based upon the current radial design and can be fabricated at Texas A&M University. The coil design was highly successful in the radial magnetic bearing. Vendors were contacted about fabrication of the high temperature lamination stack. Stress analysis was done on the laminations. Some of the components were procured, but due to budget cuts, the facility build up was stopped.

  10. Development of Novel Magnetic Nanoparticles for Hyperthermia Cancer Therapy.

    PubMed

    Cassim, Shiraz M; Giustini, Andrew J; Baker, Ian; Hoopes, P Jack

    2011-02-23

    Advances in magnetic nanoparticle hyperthermia are opening new doors in cancer therapy. As a standalone or adjuvant therapy this new modality has the opportunity significantly advance thermal medicine. Major advantages of using magnetic magnetite (Fe3O4) nanoparticles are their highly localized power deposition and the fact that the alternating magnetic fields (AMF) used to excite them can penetrate deeply into the body without harmful effect. One limitation, however, which hinders the technology, is the problem of inductive heating of normal tissue by the AMF if the frequency and fields strength are not appropriately matched to the tissue. Restricting AMF amplitude and frequency limits the heat dose which can be selectively applied to cancerous tissue via the magnetic nanoparticle, thus lowering therapeutic effect. In an effort to address this problem, particles with optimized magnetic properties must be developed. Using particles with higher saturation magnetizations and coercivity will enhance hysteresis heating increasing particle power density at milder AMF strengths and frequencies. In this study we used oil in water microemulsions to develop nanoparticles with zero-valent Fe cores and magnetite shells. The superior magnetic properties of zero-valent Fe give these particles the potential for improved SAR over pure magnetite particles. Silane and subsequently dextran have been attached to the particle surface in order to provide a biocompatible surfactant coating. The heating capability of the particles was tested in-vivo using a mouse tumor model. Although we determined that the final stage of synthesis, purification of the dextran coated particles, permits significant corrosion/oxidation of the iron core to hematite, the particles can effectively heat tumor tissue. Improving the purification procedure will allow the generation Fe/Fe3O4 with superior SAR values. PMID:24619487

  11. Development of novel magnetic nanoparticles for hyperthermia cancer therapy

    NASA Astrophysics Data System (ADS)

    Cassim, Shiraz M.; Giustini, Andrew J.; Baker, Ian; Hoopes, P. Jack

    2011-03-01

    Advances in magnetic nanoparticle hyperthermia are opening new doors in cancer therapy. As a standalone or adjuvant therapy this new modality has the opportunity significantly advance thermal medicine. Major advantages of using magnetic magnetite (Fe3O4) nanoparticles are their highly localized power deposition and the fact that the alternating magnetic fields (AMF) used to excite them can penetrate deeply into the body without harmful effect. One limitation, however, which hinders the technology, is the problem of inductive heating of normal tissue by the AMF if the frequency and fields strength are not appropriately matched to the tissue. Restricting AMF amplitude and frequency limits the heat dose which can be selectively applied to cancerous tissue via the magnetic nanoparticle, thus lowering therapeutic effect. In an effort to address this problem, particles with optimized magnetic properties must be developed. Using particles with higher saturation magnetizations and coercivity will enhance hysteresis heating increasing particle power density at milder AMF strengths and frequencies. In this study we used oil in water microemulsions to develop nanoparticles with zero-valent Fe cores and magnetite shells. The superior magnetic properties of zero-valent Fe give these particles the potential for improved SAR over pure magnetite particles. Silane and subsequently dextran have been attached to the particle surface in order to provide a biocompatible surfactant coating. The heating capability of the particles was tested in-vivo using a mouse tumor model. Although we determined that the final stage of synthesis, purification of the dextran coated particles, permits significant corrosion/oxidation of the iron core to hematite, the particles can effectively heat tumor tissue. Improving the purification procedure will allow the generation Fe/Fe3O4 with superior SAR values.

  12. Development of Novel Magnetic Nanoparticles for Hyperthermia Cancer Therapy

    PubMed Central

    Cassim, Shiraz M.; Giustini, Andrew J.; Baker, Ian; Hoopes, P. Jack

    2013-01-01

    Advances in magnetic nanoparticle hyperthermia are opening new doors in cancer therapy. As a standalone or adjuvant therapy this new modality has the opportunity significantly advance thermal medicine. Major advantages of using magnetic magnetite (Fe3O4) nanoparticles are their highly localized power deposition and the fact that the alternating magnetic fields (AMF) used to excite them can penetrate deeply into the body without harmful effect. One limitation, however, which hinders the technology, is the problem of inductive heating of normal tissue by the AMF if the frequency and fields strength are not appropriately matched to the tissue. Restricting AMF amplitude and frequency limits the heat dose which can be selectively applied to cancerous tissue via the magnetic nanoparticle, thus lowering therapeutic effect. In an effort to address this problem, particles with optimized magnetic properties must be developed. Using particles with higher saturation magnetizations and coercivity will enhance hysteresis heating increasing particle power density at milder AMF strengths and frequencies. In this study we used oil in water microemulsions to develop nanoparticles with zero-valent Fe cores and magnetite shells. The superior magnetic properties of zero-valent Fe give these particles the potential for improved SAR over pure magnetite particles. Silane and subsequently dextran have been attached to the particle surface in order to provide a biocompatible surfactant coating. The heating capability of the particles was tested in-vivo using a mouse tumor model. Although we determined that the final stage of synthesis, purification of the dextran coated particles, permits significant corrosion/oxidation of the iron core to hematite, the particles can effectively heat tumor tissue. Improving the purification procedure will allow the generation Fe/Fe3O4 with superior SAR values. PMID:24619487

  13. Dissociating Averageness and Attractiveness: Attractive Faces Are Not Always Average

    ERIC Educational Resources Information Center

    DeBruine, Lisa M.; Jones, Benedict C.; Unger, Layla; Little, Anthony C.; Feinberg, David R.

    2007-01-01

    Although the averageness hypothesis of facial attractiveness proposes that the attractiveness of faces is mostly a consequence of their averageness, 1 study has shown that caricaturing highly attractive faces makes them mathematically less average but more attractive. Here the authors systematically test the averageness hypothesis in 5 experiments…

  14. Interocular conflict attracts attention.

    PubMed

    Paffen, Chris L E; Hessels, Roy S; Van der Stigchel, Stefan

    2012-02-01

    During binocular rivalry, perception alternates.between dissimilar images presented dichoptically. Since.its discovery, researchers have debated whether the phenomenon is subject to attentional control. While it is now clear that attentional control over binocular rivalry is possible, the opposite is less evident: Is interocular conflict (i.e., the situation leading to binocular rivalry) able to attract attention?In order to answer this question, we used a change blindness paradigm in which observers looked for salient changes in two alternating frames depicting natural scenes. Each frame contained two images: one for the left and one for the right eye. Changes occurring in a single image (monocular) were detected faster than those occurring in both images (binocular). In addition,monocular change detection was also faster than detection in fused versions of the changed and unchanged regions. These results show that interocular conflict is capable of attracting attention, since it guides visual attention toward salient changes that otherwise would remain unnoticed for longer. The results of a second experiment indicated that interocular conflict attracts attention during the first phase of presentation, a phase during which the stimulus is abnormally fused [added]. PMID:22167536

  15. Development of ex situ processed MgB 2 wires and their applications to magnets

    NASA Astrophysics Data System (ADS)

    Braccini, Valeria; Nardelli, Davide; Penco, Roberto; Grasso, Giovanni

    2007-06-01

    In spite of the relatively short time dedicated to the development of magnesium diboride conductors since its discovery in early 2001, a substantial improvement was soon achieved in their manufacture and use. Unlike many others HTS and LTS materials, the MgB 2 conductor processing is more open to a number of improvements and modifications that help in making it more attractive for several DC and AC applications. Many kilometres of conductors were already produced throughout the world and it is now possible to start seriously thinking about a systematic industrial production of this material, as it is already possible to purchase it in reasonable lengths on the free market. These remarkable lengths of conductor were also wound in coils and their performance continuously improved in the past years. Here we will present a review of the recent results and a perspective for the future development of this “new” superconductor, starting from the optimisation of the precursor powders needed to improve the magnetic field behaviour of the tapes, to the conductor development, i.e. the production of multifilamentary Cu-stabilized tapes in lengths up to 1.78 km, to the realization of the first large-scale application devices such as MRI magnets and fault current limiters.

  16. Thin Magnetically Soft Wires for Magnetic Microsensors

    PubMed Central

    Zhukova, Valentina; Ipatov, Mihail; Zhukov, Arcady

    2009-01-01

    Recent advances in technology involving magnetic materials require development of novel advanced magnetic materials with improved magnetic and magneto-transport properties and with reduced dimensionality. Therefore magnetic materials with outstanding magnetic characteristics and reduced dimensionality have recently gained much attention. Among these magnetic materials a family of thin wires with reduced geometrical dimensions (of order of 1–30 μm in diameter) have gained importance within the last few years. These thin wires combine excellent soft magnetic properties (with coercivities up to 4 A/m) with attractive magneto-transport properties (Giant Magneto-impedance effect, GMI, Giant Magneto-resistance effect, GMR) and an unusual re-magnetization process in positive magnetostriction compositions exhibiting quite fast domain wall propagation. In this paper we overview the magnetic and magneto-transport properties of these microwires that make them suitable for microsensor applications. PMID:22291562

  17. Development of Magnetic Microcalorimeters for Gamma-Ray Spectroscopy

    NASA Astrophysics Data System (ADS)

    Le, L. N.; Hummatov, R.; Hall, J. A.; Cantor, R. C.; Boyd, S. T. P.

    2016-01-01

    Integrating the SQUIDs and sensing coils of magnetic microcalorimeters onto the same die is a promising approach for maximizing flux coupling and signal/noise. However, new challenges in microfabrication must be overcome, because the underlying SQUID devices are sensitive to chemical attack and elevated processing temperatures. In this report, we describe development and details of a microfabrication process for integrated SQUID/sensor gamma-ray magnetic microcalorimeters with electroformed gold absorbers, starting from a modified version of the STAR Cryoelectronics "Delta 1000" Josephson Junction process.

  18. Malformations of cortical development: 3T magnetic resonance imaging features

    PubMed Central

    Battal, Bilal; Ince, Selami; Akgun, Veysel; Kocaoglu, Murat; Ozcan, Emrah; Tasar, Mustafa

    2015-01-01

    Malformation of cortical development (MCD) is a term representing an inhomogeneous group of central nervous system abnormalities, referring particularly to embriyological aspect as a consequence of any of the three developmental stages, i.e., cell proliferation, cell migration and cortical organization. These include cotical dysgenesis, microcephaly, polymicrogyria, schizencephaly, lissencephaly, hemimegalencephaly, heterotopia and focal cortical dysplasia. Since magnetic resonance imaging is the modality of choice that best identifies the structural anomalies of the brain cortex, we aimed to provide a mini review of MCD by using 3T magnetic resonance scanner images. PMID:26516429

  19. Development of Magnetic Microcalorimeters for Gamma-Ray Spectroscopy

    NASA Astrophysics Data System (ADS)

    Le, L. N.; Hummatov, R.; Hall, J. A.; Cantor, R. C.; Boyd, S. T. P.

    2016-07-01

    Integrating the SQUIDs and sensing coils of magnetic microcalorimeters onto the same die is a promising approach for maximizing flux coupling and signal/noise. However, new challenges in microfabrication must be overcome, because the underlying SQUID devices are sensitive to chemical attack and elevated processing temperatures. In this report, we describe development and details of a microfabrication process for integrated SQUID/sensor gamma-ray magnetic microcalorimeters with electroformed gold absorbers, starting from a modified version of the STAR Cryoelectronics "Delta 1000" Josephson Junction process.

  20. TECHNOLOGY DEVELOPMENT FOR REACT AND WIND COMMON COIL MAGNETS.

    SciTech Connect

    ESCALLIER,J.; ANERELLA,M.; COZZOLINO,J.; GANETIS,G.; GHOSH,A.; GUPTA,R.; HARRISON,M.; MARONE,A.; MURATORE,J.; PARKER,B.; SAMPSON,W.; WANDERER,P.

    2001-06-18

    High field common coil magnets [1,2] using brittle High Temperature Superconductors (HTS) or Nb{sub 3}Sn cables provide new challenges with respect to the design and manufacturing of coils. We are developing the scaleable techniques that can be used in the production of common coil or other magnets with similar designs [3,4]. By utilizing a cost-effective rapid turnaround short coil program, it is possible to quickly develop and test the new conductors and learn the design and manufacturing concepts needed for them. The flexible nature of a rapid turnaround program required the development of a standard coil cassette for different size cable, allowing coils to be used as building blocks for testing in different magnet configurations. Careful attention is given to the design of the coil structure: The inner bobbin the wire is wound on, the coil winding process, insulation integrity, epoxy vacuum impregnation, and final assembly into a test magnet. This paper will discuss the manufacturing techniques and design rules learned from the rapid turnaround program, and test results to date.

  1. Development and test of LARP technological quadrupole (TQC) magnet

    SciTech Connect

    Feher, S.; Bossert, R.C.; Ambrosio, G.; Andreev, N.; Barzi, E.; Carcagno, R.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, F.; Novitski, I.; /Fermilab /LBL, Berkeley

    2006-08-01

    In support of the development of a large-aperture Nb{sub 3}Sn superconducting quadrupole for the Large Hadron Collider (LHC) luminosity upgrade, two-layer quadrupole models (TQC and TQS) with 90-mm aperture are being constructed at Fermilab and LBNL within the framework of the US LHC Accelerator Research Program (LARP). This paper describes the construction and test of model TQC01. ANSYS calculations of the structure are compared with measurements during construction. Fabrication experience is described and in-process measurements are reported. Test results at 4.5K are presented, including magnet training, current ramp rate studies and magnet quench current . Results of magnetic measurements at helium temperature are also presented.

  2. Development and Test of LARP Technological Quadrupole (TQC) Magnet

    SciTech Connect

    Feher, S.; Bossert, R.C.; Ambrosio, G.; Andreev, N.; Barzi, E.; Carcagno, R.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, F.; Novitski, I.; Pischalnikov, Yu.; Sylvester, C.; Tartaglia, M.; Turrioni, D.; Whitson, G.; Yamada, R.; Zlobin, A.V.; Caspi, S.; Dietderich, D.; Ferracin, P.; Hannaford, R.; Hafalia, A.R.; Sabbi, G.

    2007-06-01

    In support of the development of a large-aperture Nb{sub 3}Sn superconducting quadrupole for the Large Hadron Collider (LHC) luminosity upgrade, two-layer quadrupole models (TQC and TQS) with 90 mm aperture are being constructed at Fermilab and LBNL within the framework of the US LHC Accelerator Research Program (LARP). This paper describes the construction and test of model TQC01. ANSYS calculations of the structure are compared with measurements during construction. Fabrication experience is described and in-process measurements are reported. Test results at 4.5 K are presented, including magnet training, current ramp rate studies and magnet quench current. Results of magnetic measurements at helium temperature are also presented.

  3. New magnetic fluid developed with natural organic compounds biocompatible.

    PubMed

    Santos, J G; Silveira, L B; Fegueredo, P H S; Araújo, B F; Peternele, W S; Rodriguez, A F R; Vilela, E C; Garg, V K; Oliveira, A C; Azevedo, R B; Morais, P C

    2012-06-01

    This work was developed with an aqueous suspension of maghemite nanoparticles and colloidal emulsions with nanoparticles of magnetite. The nanoparticles were synthesized by co-precipitation method. The first was the magnetic emulsion nanoparticles of maghemite dispersed in the aqueous extract obtained from the leaf embauba (Cecropia Obtusifolia), whose tree is native to Central and South America. Thereby achieving the magnetic fluid extract embauba stabilized with ionic buffer solution pH 7.4. A second emulsion was prepared with colloidal magnetite nanoparticles with surfaces previously coated with oleic acid as a means of dispersing and using the oil extracted from in nature seed Andiroba (Carapa Guianensis), tree of the Brazilian Amazon. These new magnetic fluids the nanoparticles were characterized by Photoacoustic spectroscopy (PAS) to determine the coating layer of molecules on the surfaces of nanoparticles. In aqueous ionic magnetic fluid Cecropia Obtusifolia (MFCO) chlorogenic acid contributes to the electron density in the presence of four groups alcohols, a ketone group and a carboxylic group. In magnetic fluid-based oil andiroba MFAD PAS spectra show that oleic acid molecules are tightly linked on the surface of the nanoparticles. PMID:22905527

  4. Are Brazil Nuts Attractive?

    NASA Astrophysics Data System (ADS)

    Sanders, Duncan A.; Swift, Michael R.; Bowley, R. M.; King, P. J.

    2004-11-01

    We present event-driven simulation results for single and multiple intruders in a vertically vibrated granular bed. Under our vibratory conditions, the mean vertical position of a single intruder is governed primarily by a buoyancylike effect. Multiple intruders also exhibit buoyancy governed behavior; however, multiple neutrally buoyant intruders cluster spontaneously and undergo horizontal segregation. These effects can be understood by considering the dynamics of two neutrally buoyant intruders. We have measured an attractive force between such intruders which has a range of five intruder diameters, and we provide a mechanistic explanation for the origins of this force.

  5. Development of training modules for magnetic particle inspection

    NASA Astrophysics Data System (ADS)

    Kosaka, Daigo; Eisenmann, David J.; Enyart, Darrel; Nakagawa, Norio; Lo, Chester; Orman, David

    2015-03-01

    Magnetic particle inspection (MPI) is a nondestructive evaluation technique used with ferromagnetic materials. Although the application of this method may appear straightforward, MPI combines the complicated nature of electromagnetics, metallurgical material effects, fluid-particle motion dynamics, and physiological human factors into a single inspection. To fully appreciate industry specifications such as ASTM E-1444, users should develop a basic understanding of the many factors that are involved in MPI. We have developed a series of MPI training modules that are aimed at addressing this requirement. The modules not only offer qualitative explanations, but also show quantitative explanations in terms of measurement and numerical simulation data in many instances. There are five modules in all. Module ♯1 shows characteristics of waveforms and magnetizing methods. This allows MPI practitioners to make optimum choice of waveform and magnetizing method. Module ♯2 explains how material properties relate to the magnetic characteristics. Module ♯3 shows the strength of the excitation field or the flux leakage from a crack and how it compares to the detectability of a crack by MPI. Module ♯4 shows how specimen status may influence defect detection. Module ♯5 shows the effects of particle properties on defect detection.

  6. Like Charges Attract?

    PubMed

    Zhao, Tianshan; Zhou, Jian; Wang, Qian; Jena, Puru

    2016-07-21

    Using multiscale first-principles calculations, we show that two interacting negatively charged B12I9(-) monoanions not only attract, in defiance of the Coulomb's law, but also the energy barrier at 400 K is small enough that these two moieties combine to form a stable B24I18(2-) moiety. Ab initio molecular dynamics simulations further confirm its stability up to 1500 K. Studies of other B12X9(-) (X = Br, Cl, F, H, Au, CN) show that while all of these B24X18(2-) moieties are stable against dissociation, the energy barrier, with the exception of B24Au18(2-), is large so as to hinder their experimental observation. Our results explain the recent experimental observation of the "spontaneous" formation of B24I18(2-) in an ion trap. A simple model based upon electrostatics shows that this unusual behavior is due to competition between the attractive dipole-dipole interaction caused by the aspherical shape of the particle and the repulsive interaction between the like charges. PMID:27351125

  7. Development and evaluation of an attractive self-marking ovitrap to measure dispersal and determine skip oviposition in Aedes albopictus(Diptera:Culicidae) field populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aedes albopictus (Skuse) is a container-breeding mosquito of public health importance. Its oviposition behavior has been assessed in outdoor conditions, but only with laboratory-reared specimens. We used an attractive self-marking oviposition device to assess Ae. albopictus skip oviposition behavi...

  8. Magnet Healing?

    NASA Astrophysics Data System (ADS)

    Finegold, Leonard

    2000-03-01

    Many people are convinced that static magnets—applied to their skin—will heal ills, and many businesses sell such magnets. The biophysics of such healing was reviewed [1] together with the general biophysics of static fields. Birds and insects do use the earth’s magnetic field for navigation. While insect and frog egg development can clearly be influenced by high fields (7 T and 17 T respectively), there is no experimental evidence that small magnetic fields (of less than 0.5 T) might heal, and much evidence that they cannot heal. A puzzle to the physics community is: How to show laypersons that simple magnets (very probably) do not heal, however attractive that idea might be. [1] L. Finegold, The Physics of "Alternative Medicine": Magnet Therapy, The Scientific Review of Alternative Medicine 3:26-33 (1999).

  9. Development of magnetic Fe-based metallic glasses without metalloids

    SciTech Connect

    Mastrogiacomo, Giovanni; Kradolfer, Juerg; Loeffler, Joerg F.

    2006-01-15

    The glass-forming ability of Fe-based metallic glasses has a direct relationship with their metalloid content. A good glass-former usually needs a metalloid content of approximately 20 at. %. However, a high metalloid content causes deterioration not only in magnetic properties but also in elasticity and plasticity. Based on destabilization of the solid state we have developed a series of metalloid-free Fe-based metallic glasses of composition (Fe{sub 0.582}Co{sub 0.418}){sub 100-x-y}Cr{sub x}Zr{sub y} (10{<=}x{<=}28 and 8{<=}y{<=}11). Via this destabilization the liquid state is stabilized, which results in a decreasing liquidus temperature. The mechanical and magnetic properties of the metalloid-free Fe-based metallic glass with the highest Fe and Co fractions were analyzed. The alloy of composition (Fe{sub 0.582}Co{sub 0.418}){sub 80}Cr{sub 10}Zr{sub 10} exhibits bending elasticity and plasticity. Magnetization measurements reveal a saturation magnetization of up to 1.1 T and an inverted hysteresis. The origin of this inverted hysteresis presumably lies in the inclination to decompose in a ferromagnetic iron-rich {alpha}{sub 1} phase and an antiferromagnetic chromium-rich {alpha}{sub 2} phase.

  10. Development of a prototype magnetically suspended rotor ventricular assist device.

    PubMed

    Bearnson, G B; Maslen, E H; Olsen, D B; Allaire, P E; Khanwilkar, P S; Long, J W; Kim, H C

    1996-01-01

    A continuous flow centrifugal blood pump with magnetically suspended impeller has been designed, constructed, and tested. The system can be functionally divided into three subsystem designs: 1) centrifugal pump and flow paths, 2) magnetic bearings, and 3) brushless DC motor. The centrifugal pump is a Francis vane type design with a designed operating point of 6 L/min flow and 100 mmHg pressure rise at 2,300 RPM. Peak hydraulic efficiency is over 50%. The magnetic bearing system is an all active design with five axes of control. Rotor position sensors were developed as part of the system to provide feedback to a proportional-integral-derivative controller. The motor is a sensorless brushless DC motor. Back electromotive force voltage generated by the motor is used to provide commutation for the motor. No slots are employed in the motor design in order to reduce the radial force that the bearings must generate. Tests pumping blood in vitro were very encouraging; an index of hemolysis of 0.0086 +/- 0.0012 was measured. Further design refinement is needed to reduce power dissipation and size of the device. The concept of using magnetic bearings in a blood pump shows promise in a long-term implantable blood pump. PMID:8828784

  11. Development and performance study of a magnetic aerostatic vibration isolation platform

    NASA Astrophysics Data System (ADS)

    Chang, Keng-Ning; Huang, Kuang-Yuh

    2012-04-01

    This paper presents our development of a compact and magnetic-aerostatic vibration isolation platform for small equipments such as AFM-system, which combines the electromagnetic and aerostatic principles to create a semiactive damping effect. For the aerostatic principle, the concept of cap-shaped bearing form is applied to combine radial and axial bearings inside a cap-shaped air film to enhance the bearing capacity. The axial aerostatic bearing provides the main supporting force for the vibration isolation platform, and the radial aerostatic bearing creates frictionless and accurate guide for the platform. The electromagnetic coil is used to generate attractive force to counterbalance the axial aerostatic bearing force. Through this force counterbalance, not only the axial bearing stiffness can be minimized but also the axial position of the platform can be precisely controlled. In the axial positioning control, a hall element and a magnet are used to realize a non-contact displacement measurement with less loading effect. Besides, the robust PID control algorithm is chosen as the main core of the positioning control. For optimization and performance verification, finite element analyses and experiments are carried out to comprehend its electromagnetic and aerostatic effects.

  12. Development of a suspension type sliding planar motion table using magnetic fluid lubrication

    NASA Astrophysics Data System (ADS)

    Li, Xinghui; Shinshi, Tadahiko; Hijikata, Wataru; Morimoto, Yoshihiro

    2016-06-01

    A sliding planar motion table system that can be used for the lens driving actuator of a laser cutting machine was developed. The system uses magnetic fluid as the lubricant to avoid the leakage of lubricating oil under the table and reduce environmental pollution. The motion table is suspended from the guide surface by an attractive force generated by electromagnets to reduce the contact and frictional forces between the table and the guide surface. The table is capable of movement in one rotational and two translational directions over the guide surface using six electromagnets and three non-contact displacement sensors. Experimental results showed that the magnetic suspension of the table reduced the friction by 82.1% compared to the friction that would otherwise be generated by the dead weight of the table. Circular motion within a diameter of 2 mm was achieved with resolutions of 5 μm and 20 μrad in the translational and rotational directions, respectively. A bandwidth of higher than 100 Hz was also achieved in the three movement directions.

  13. Development of a suspension type sliding planar motion table using magnetic fluid lubrication.

    PubMed

    Li, Xinghui; Shinshi, Tadahiko; Hijikata, Wataru; Morimoto, Yoshihiro

    2016-06-01

    A sliding planar motion table system that can be used for the lens driving actuator of a laser cutting machine was developed. The system uses magnetic fluid as the lubricant to avoid the leakage of lubricating oil under the table and reduce environmental pollution. The motion table is suspended from the guide surface by an attractive force generated by electromagnets to reduce the contact and frictional forces between the table and the guide surface. The table is capable of movement in one rotational and two translational directions over the guide surface using six electromagnets and three non-contact displacement sensors. Experimental results showed that the magnetic suspension of the table reduced the friction by 82.1% compared to the friction that would otherwise be generated by the dead weight of the table. Circular motion within a diameter of 2 mm was achieved with resolutions of 5 μm and 20 μrad in the translational and rotational directions, respectively. A bandwidth of higher than 100 Hz was also achieved in the three movement directions. PMID:27370485

  14. Development of a Magnetic Nanoparticle Susceptibility Magnitude Imaging Array

    PubMed Central

    Ficko, Bradley W.; Nadar, Priyanka M.; Hoopes, P. Jack; Diamond, Solomon G.

    2014-01-01

    There are several emerging diagnostic and therapeutic applications of magnetic nanoparticles (mNPs) in medicine. This study examines the potential for developing an mNP imager that meets these emerging clinical needs with a low cost imaging solution that uses arrays of digitally controlled drive coils in a multiple-frequency, continuous-wave operating mode and compensated fluxgate magnetometers. The design approach is described and a mathematical model is developed to support measurement and imaging. A prototype is used to demonstrate active compensation of up to 185 times the primary applied magnetic field, depth sensitivity up to 2.5 cm (p < 0.01), and linearity over 5 dilutions (R2 > 0.98, p <0.001). System frequency responses show distinguishable readouts for iron oxide mNPs with single magnetic domain core diameters of 10 nm and 40 nm, and multi-domain mNPs with a hydrodynamic diameter of 100 nm. Tomographic images show a contrast-to-noise ratio of 23 for 0.5 ml of 12.5 mg Fe/ml mNPs at 1 cm depth. A demonstration involving the injection of mNPs into pork sausage shows the potential for use in biological systems. These results indicate that the proposed mNP imaging approach can potentially be extended to a larger array system with higher-resolution. PMID:24504184

  15. Development of a magnetic nanoparticle susceptibility magnitude imaging array.

    PubMed

    Ficko, Bradley W; Nadar, Priyanka M; Hoopes, P Jack; Diamond, Solomon G

    2014-02-21

    There are several emerging diagnostic and therapeutic applications of magnetic nanoparticles (mNPs) in medicine. This study examines the potential for developing an mNP imager that meets these emerging clinical needs with a low cost imaging solution that uses arrays of digitally controlled drive coils in a multiple-frequency, continuous-wave operating mode and compensated fluxgate magnetometers. The design approach is described and a mathematical model is developed to support measurement and imaging. A prototype is used to demonstrate active compensation of up to 185 times the primary applied magnetic field, depth sensitivity up to 2.5 cm (p < 0.01), and linearity over five dilutions (R(2) > 0.98, p < 0.001). System frequency responses show distinguishable readouts for iron oxide mNPs with single magnetic domain core diameters of 10 and 40 nm, and multi-domain mNPs with a hydrodynamic diameter of 100 nm. Tomographic images show a contrast-to-noise ratio of 23 for 0.5 ml of 12.5 mg Fe ml(-1) mNPs at 1 cm depth. A demonstration involving the injection of mNPs into pork sausage shows the potential for use in biological systems. These results indicate that the proposed mNP imaging approach can potentially be extended to a larger array system with higher-resolution. PMID:24504184

  16. Development of a magnetic nanoparticle susceptibility magnitude imaging array

    NASA Astrophysics Data System (ADS)

    Ficko, Bradley W.; Nadar, Priyanka M.; Hoopes, P. Jack; Diamond, Solomon G.

    2014-02-01

    There are several emerging diagnostic and therapeutic applications of magnetic nanoparticles (mNPs) in medicine. This study examines the potential for developing an mNP imager that meets these emerging clinical needs with a low cost imaging solution that uses arrays of digitally controlled drive coils in a multiple-frequency, continuous-wave operating mode and compensated fluxgate magnetometers. The design approach is described and a mathematical model is developed to support measurement and imaging. A prototype is used to demonstrate active compensation of up to 185 times the primary applied magnetic field, depth sensitivity up to 2.5 cm (p < 0.01), and linearity over five dilutions (R2 > 0.98, p < 0.001). System frequency responses show distinguishable readouts for iron oxide mNPs with single magnetic domain core diameters of 10 and 40 nm, and multi-domain mNPs with a hydrodynamic diameter of 100 nm. Tomographic images show a contrast-to-noise ratio of 23 for 0.5 ml of 12.5 mg Fe ml-1 mNPs at 1 cm depth. A demonstration involving the injection of mNPs into pork sausage shows the potential for use in biological systems. These results indicate that the proposed mNP imaging approach can potentially be extended to a larger array system with higher-resolution.

  17. Development of Microfabricated Magnetic Actuators for Removing Cellular Occlusion

    PubMed Central

    Lee, Selene A.; Lee, Hyowon; Pinney, James R; Khialeeva, Elvira; Bergsneider, Marvin; Judy, Jack W.

    2011-01-01

    Here we report on the development of torsional magnetic microactuators for displacing biological materials in implantable catheters. Static and dynamic behaviors of the devices were characterized in air and in fluid using optical experimental methods. The devices were capable of achieving large deflections (>60°) and had resonant frequencies that ranged from 70 Hz to 1.5 kHz in fluid. The effect of long-term actuation (>2.5 · 108 cycles) was quantified using resonant shift as the metric (Δf < 2%). Cell-clearing capabilities of the devices were evaluated by examining the effect of actuation on a layer of aggressively growing adherent cells. On average, actuated microdevices removed 37.4% of the adherent cell layer grown over the actuator surface. The effect of actuation time, deflection angle, and beam geometry were evaluated. The experimental results indicate that physical removal of adherent cells at the microscale is feasible using magnetic microactuation. PMID:21886945

  18. Development testing of a magnetic bearing centrifugal chiller

    SciTech Connect

    Benedict, S.M.; Cole, G.S.; Gottschlich, J.

    1998-07-01

    Mainstream Engineering Corporation is developing a lubrication-free centrifugal compressor for high efficiency chiller applications which relies on magnetic bearing technology to support the rotor. This paper presents experimental results of a test program to evaluate the mechanical, thermodynamic, and aerodynamic performance of a high speed, single stage, direct drive centrifugal compressor for chiller applications. The focus is on low capacity centrifugal compressors. The authors present measurements of the compressor efficiency over a wide range of compressor speeds and inlet refrigerant superheat. Measurements show that isentropic efficiencies in excess of 0.80 are attainable over a wide range of operating conditions. This paper also describes a 110 ton chiller which utilizes two such magnetic bearing centrifugal compressors, with HFC-227ea refrigerant, and a user-friendly control system.

  19. Perceived Attractiveness and Classroom Interactions

    ERIC Educational Resources Information Center

    Algozzine, Bob

    1977-01-01

    Adams and Cohen (1974) demonstrated that facial attractiveness was a salient factor in differential student-teacher interactions. This research investigates further the interaction between teachers and children perceived to be attractive or unattractive by those teachers. It was hypothesized that attractive children would exhibit more "positive,"…

  20. Development of Metallic Magnetic Calorimeters for Nuclear Safeguards Applications

    SciTech Connect

    Bates, Cameron Russell

    2015-03-11

    Many nuclear safeguards applications could benefit from high-resolution gamma-ray spectroscopy achievable with metallic magnetic calorimeters. This dissertation covers the development of a system for these applications based on gamma-ray detectors developed at the University of Heidelberg. It demonstrates new calorimeters of this type, which achieved an energy resolution of 45.5 eV full-width at half-maximum at 59.54 keV, roughly ten times better than current state of the art high purity germanium detectors. This is the best energy resolution achieved with a gamma-ray metallic magnetic calorimeter at this energy to date. In addition to demonstrating a new benchmark in energy resolution, an experimental system for measuring samples with metallic magnetic calorimeters was constructed at Lawrence Livermore National Laboratory. This system achieved an energy resolution of 91.3 eV full-width at half-maximum at 59.54 keV under optimal conditions. Using this system it was possible to characterize the linearity of the response, the count-rate limitations, and the energy resolution as a function of temperature of the new calorimeter. With this characterization it was determined that it would be feasible to measure 242Pu in a mixed isotope plutonium sample. A measurement of a mixed isotope plutonium sample was performed over the course of 12 days with a single two-pixel metallic magnetic calorimeter. The relative concentration of 242Pu in comparison to other plutonium isotopes was determined by direct measurement to less than half a percent accuracy. This is comparable with the accuracy of the best-case scenario using traditional indirect methods. The ability to directly measure the relative concentration of 242Pu in a sample could enable more accurate accounting and detection of indications of undeclared activities in nuclear safeguards, a better constraint on source material in forensic samples containing plutonium, and improvements in verification in a future plutonium

  1. Development of Metallic Magnetic Calorimeters for Nuclear Safeguards Applications

    NASA Astrophysics Data System (ADS)

    Bates, Cameron Russell

    Many nuclear safeguards applications could benefit from high-resolution gamma-ray spectroscopy achievable with metallic magnetic calorimeters. This dissertation covers the development of a system for these applications based on gamma-ray detectors developed at the University of Heidelberg. It demonstrates new calorimeters of this type, which achieved an energy resolution of 45.5 eV full-width at half-maximum at 59.54 keV, roughly ten times better than current state of the art high purity germanium detectors. This is the best energy resolution achieved with a gamma-ray metallic magnetic calorimeter at this energy to date. In addition to demonstrating a new benchmark in energy resolution, an experimental system for measuring samples with metallic magnetic calorimeters was constructed at Lawrence Livermore National Laboratory. This system achieved an energy resolution of 91.3 eV full-width at half-maximum at 59.54 keV under optimal conditions. Using this system it was possible to characterize the linearity of the response, the count-rate limitations, and the energy resolution as a function of temperature of the new calorimeter. With this characterization it was determined that it would be feasible to measure 242Pu in a mixed isotope plutonium sample. A measurement of a mixed isotope plutonium sample was performed over the course of 12 days with a single two-pixel metallic magnetic calorimeter. The relative concentration of 242Pu in comparison to other plutonium isotopes was determined by direct measurement to less than half a percent accuracy. This is comparable with the accuracy of the best-case scenario using traditional indirect methods. The ability to directly measure the relative concentration of 242Pu in a sample could enable more accurate accounting and detection of indications of undeclared activities in nuclear safeguards, a better constraint on source material in forensic samples containing plutonium, and improvements in verification in a future plutonium

  2. Development of REBCO HTS Magnet of Magnetic Bearing for Large Capacity Flywheel Energy Storage System

    NASA Astrophysics Data System (ADS)

    Mukoyama, Shinichi; Matsuoka, Taro; Furukawa, Makoto; Nakao, Kengo; Nagashima, Ken; Ogata, Masafumi; Yamashita, Tomohisa; Hasegawa, Hitoshi; Yoshizawa, Kazuhiro; Arai, Yuuki; Miyazaki, Kazuki; Horiuchi, Shinichi; Maeda, Tadakazu; Shimizu, Hideki

    A flywheel energy storage system (FESS) is a promising electrical storage system that moderates fluctuation of electrical power from renewable energy sources. The FESS can charge and discharge the surplus electrical power repetitively with the rotating energy. Particularly, the FESS that utilizes a high temperature superconducting magnetic bearing (HTS bearing) is lower loss than conventional FESS that has mechanical bearing, and has property of longer life operation than secondary batteries. The HTS bearing consists of a HTS bulk and double-pancake coils used 2nd generation REBCO wires. In the development, the HTS double-pancake coils were fabricated and were provided for a levitation test to verify the possibility of the HTS bearing. We successfully confirmed the magnetic field was achieved to design value, and levitation force in the configuration of one YBCO bulk and five double pan-cake coils was obtained to a satisfactory force of 39.2 kN (4 tons).

  3. Chemistry of sex attraction.

    PubMed Central

    Roelofs, W L

    1995-01-01

    The chemical communication system used to attract mates involves not only the overt chemical signals but also indirectly a great deal of chemistry in the emitter and receiver. As an example, in emitting female moths, this includes enzymes (and cofactors, mRNA, genes) of the pheromone biosynthetic pathways, hormones (and genes) involved in controlling pheromone production, receptors and second messengers for the hormones, and host plant cues that control release of the hormone. In receiving male moths, this includes the chemistry of pheromone transportation in antennal olfactory hairs (binding proteins and sensillar esterases) and the chemistry of signal transduction, which includes specific dendritic pheromone receptors and a rapid inositol triphosphate second messenger signal. A fluctuating plume structure is an integral part of the signal since the antennal receptors need intermittent stimulation to sustain upwind flight. Input from the hundreds of thousands of sensory cells is processed and integrated with other modalities in the central nervous system, but many unknown factors modulate the information before it is fed to motor neurons for behavioral responses. An unknown brain control center for pheromone perception is discussed relative to data from behavioral-threshold studies showing modulation by biogenic amines, such as octopamine and serotonin, from genetic studies on pheromone discrimination, and from behavioral and electrophysiological studies with behavioral antagonists. Images Fig. 1 PMID:7816846

  4. Development of a micro nuclear magnetic resonance system

    NASA Astrophysics Data System (ADS)

    Goloshevsky, Artem

    Application of Nuclear Magnetic Resonance (NMR) to on-line/in-line control of industrial processes is currently limited by equipment costs and requirements for installation. A superconducting magnet generating strong fields is the most expensive part of a typical NMR instrument. In industrial environments, fringe magnetic fields make accommodation of NMR instruments difficult. However, a portable, low-cost and low-field magnetic resonance system can be used in virtually any environment. Development of a number of hardware components for a portable, low-cost NMR instrument is reported in this dissertation. Chapter one provides a discussion on a miniaturized Helmholtz spiral radio-frequency (RF) coil (average diameter equal to 3.5 mm) and an NMR probe built around a capillary (outer diameter = 1.59 mm and inner diameter = 1.02 mm) for flow imaging. Experiments of NMR spectroscopy, static and dynamic (flow) imaging, conducted with the use of the miniaturized coil, are described. Chapter two presents a microfabricated package of two biaxial gradient coils and a Helmholtz RF coil. Planar configuration of discrete wires was used to create magnetic field gradients. Performance of the microfabricated gradient coils while imaging water flow compared well with a commercial gradient set of much larger size. Chapter three reports on flow imaging experiments with power law fluids (aqueous solutions of sodium salt of carboxymethyl cellulose (CMC)) of different viscosities, carried out in the NMR probe with the miniaturized RF coil and capillary. Viscosities of the CMC solutions were determined based on the curve fits of the velocity profiles and simultaneous measurements of the flow rates. The curve fits were carried out according to the power law model equations. The NMR viscosity measurements compared well with measurements of the same CMC samples, performed on a conventional rotational rheometer. A portable, home-built transceiver, designed for NMR applications utilizing a

  5. Development of a dc motor with virtually zero powered magnetic bearing

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The development of magnetic bearings for use in direct current electric motors is discussed. The characteristics of the magnets used in the construction of the bearings are described. A magnetic bearing using steel armoring on permanent magnets was selected for performance tests. The specifications of the motor are presented. The test equipment used in the evaluation is described.

  6. Development of Metallic Magnetic Calorimeters with a Critical Temperature Switch

    NASA Astrophysics Data System (ADS)

    Kim, S. R.; Choi, J.; Jo, H. S.; Kang, C. S.; Kim, G. B.; Kim, H. L.; Kim, I. W.; Lee, H. J.; Lee, J. H.; Lee, M. K.; Oh, S. Y.; Sala, E.; So, J. H.; Yoon, W. S.; Kim, Y. H.

    2016-07-01

    We report on the progress in the development of meander-shaped metallic magnetic calorimeters (MMCs) with a critical temperature switch. A niobium meander-shaped coil in an MMC is arranged to form a superconducting loop. It is to measure the change in magnetization and to apply a persistent current that magnetizes the MMC sensor material. In this work, part of the superconducting loop is fabricated with another superconducting material with its transition temperature (T_C) lower than that of niobium. A persistent current can be injected in the loop while reducing the temperature from above to below the T_C of the switch. Aluminum (Al) wires and an alloy of molybdenum and germanium (MoGe) were tested as critical temperature switch. The test with the Al switch demonstrated the temperature switch concept for meander-shaped MMCs that require a large field current. Microfabricated MoGe switches showed a T_C near 4.3 K, but only 7 mA of persistent current could be charged due to MoGe film discontinuity. This issue requires further improvement in the fabrication procedure.

  7. MAGNETS

    DOEpatents

    Hofacker, H.B.

    1958-09-23

    This patent relates to nmgnets used in a calutron and more particularly to means fur clamping an assembly of magnet coils and coil spacers into tightly assembled relation in a fluid-tight vessel. The magnet comprises windings made up of an assembly of alternate pan-cake type coils and spacers disposed in a fluid-tight vessel. At one end of the tank a plurality of clamping strips are held firmly against the assembly by adjustable bolts extending through the adjacent wall. The foregoing arrangement permits taking up any looseness which may develop in the assembly of coils and spacers.

  8. Development of a magnetic coagulant based on Moringa oleifera seed extract for water treatment.

    PubMed

    Santos, Tássia R T; Silva, Marcela F; Nishi, Leticia; Vieira, Angélica M S; Klein, Márcia R F; Andrade, Murilo B; Vieira, Marcelo F; Bergamasco, Rosângela

    2016-04-01

    In this work, to evaluate the effectiveness of the coagulation/flocculation using a natural coagulant, using Moringa oleifera Lam functionalized with magnetic iron oxide nanoparticles, producing flakes that are attracted by an external magnetic field, thereby allowing a fast settling and separation of the clarified liquid, is proposed. The removal efficiency of the parameters, apparent color, turbidity, and compounds with UV254nm absorption, was evaluated. The magnetic functionalized M. oleifera Lam coagulant could effectively remove 90 % of turbidity, 85 % of apparent color, and 50 % for the compounds with absorption at UV254nm, in surface waters under the influence of an external magnetic field within 30 min. It was found that the coagulation/flocculation treatment using magnetic functionalized M. oleifera Lam coagulant was able to reduce the values of the physico-chemical parameters evaluated with reduced settling time. PMID:26743649

  9. Making vasectomy attractive.

    PubMed

    Herndon, N

    1992-08-01

    In 1989, Pro-Pater, a private, nonprofit family planning organization in Brazil, used attractive ads with the message Vasectomy, An Act of Love to promote vasectomy. The number of vasectomies performed/day at Pro-Pater clinics increased from 11 to 20 during the publicity campaign and fell after the ads stopped but continued at higher levels. Word of mouth communication among friends, neighbors, and relatives who had vasectomies maintained these high levels. This type of communication reduced the fear that often involves vasectomies because men hear from men they know and trust that vasectomies are harmless and do not deprive them of potency. In Sao Paulo, the percentage of men familiar with vasectomies and how they are performed increased after the campaign, but in Salvador, knowledge did not increase even though the number of vasectomies in Pro-Pater clinics increased. Organizations in Colombia and Guatemala have also been effective in educating men about vasectomies. These successes were especially relevant in Latin American where machismo has been an obstacle of family planning programs. The no-scalpel technique 1st introduced in China in 1974 reduces the fear of vasectomy and has fewer complications than the conventional technique. Further trained physicians can perform the no-scalpel technique in about 10 minutes compared with 15 minutes for the conventional technique. In 1987 during a 1-day festival in Thailand, physicians averaged 57 no-scalpel vasectomies/day compared with only 33 for conventional vasectomies. This technique has not spread to Guatemala, Brazil, Colombia, the US, and some countries in Asia and Africa. Extensive research does not indicate that vasectomy has an increased risk of testicular cancer, prostate cancer, and myocardial infarction. Physicians are working on ways to improve vasectomy. PMID:12317726

  10. Formulation development and evaluation of metronidazole magnetic nanosuspension as a magnetic-targeted and polymeric-controlled drug delivery system

    NASA Astrophysics Data System (ADS)

    Latha, Subbiah; Selvamani, Palanisamy; Kumar, Chelladurai Senthil; Sharavanan, Palaniappan; Suganya, Govindan; Beniwal, Vijender Singh; Rao, Poduri Rama

    2009-05-01

    A nanosuspension of magnetically tagged metronidazole was developed by the solvent displacement method coupled with ultrasonication and was evaluated for its physicochemical properties. The drug release from metronidazole magnetic nanosuspension at pH 1.2 and 7.0 shows maximum correlation coefficient for zero order and Higuchi model, respectively. The anthelmintic activity of the formulated metronidazole magnetic nanosuspension was evaluated on Indian earthworms (Pheretima poi). Metronidazole magnetic nanosuspension at a dose of 10 and 50 mg/ml shortened by 31% and 34%, respectively, the mean time to death of the earthworms when compared against a non-magnetic metronidazole suspension. Thus, the developed metronidazole magnetic nanosuspension showed potent, controlled and targeted drug action and might be a good therapeutic avenue in combating infectious GI disorders.

  11. Superconducting Cable Development for Future High Energy Physics Detector Magnets

    NASA Astrophysics Data System (ADS)

    Horvath, I. L.

    1995-11-01

    Under the leadership of the Swiss Federal Institute of Technology (ETHZ) an international ad hoc collaboration for superconducting cables developed an aluminium stabilised superconducting cable for future detector magnets. With the financial support of the Swiss government, this R&D work was carried out for the European Organisation for Nuclear Research (CERN). In this report the manufacturing process is described and results of the quality control measurements are summarised. These tests showed that the industrial manufacturing of an aluminium stabilised superconducting cable is feasible.

  12. Magnetic field effects on plant growth, development, and evolution

    PubMed Central

    Maffei, Massimo E.

    2014-01-01

    The geomagnetic field (GMF) is a natural component of our environment. Plants, which are known to sense different wavelengths of light, respond to gravity, react to touch and electrical signaling, cannot escape the effect of GMF. While phototropism, gravitropism, and tigmotropism have been thoroughly studied, the impact of GMF on plant growth and development is not well-understood. This review describes the effects of altering magnetic field (MF) conditions on plants by considering plant responses to MF values either lower or higher than those of the GMF. The possible role of GMF on plant evolution and the nature of the magnetoreceptor is also discussed. PMID:25237317

  13. Magnetic Resonance Imaging of Alimentary Tract Development in Manduca sexta.

    PubMed

    Rowland, Ian J; Goodman, Walter G

    2016-01-01

    Non-invasive 3D magnetic resonance imaging techniques were used to investigate metamorphosis of the alimentary tract of Manduca sexta from the larval to the adult stage. The larval midgut contracts in volume immediately following cessation of feeding and then greatly enlarges during the late pharate pupal period. Magnetic resonance imaging revealed that the foregut and hindgut of the pharate pupa undergo ecdysis considerably earlier than the external exoskeleton. Expansion of air sacs in the early pupa and development of flight muscles several days later appear to orient the midgut into its adult position in the abdomen. The crop, an adult auxiliary storage organ, begins development as a dorsal outgrowth of the foregut. This coincides with a reported increase in pupal ecdysteroid titers. An outgrowth of the hindgut, the rectal sac, appears several days later and continues to expand until it nearly fills the dorsal half of the abdominal cavity. This development correlates with a second rise in pupal ecdysteroid titers. In the pharate pupa, the presence of paramagnetic species renders the silk glands hyperintense. PMID:27280776

  14. Magnetic Resonance Imaging of Alimentary Tract Development in Manduca sexta

    PubMed Central

    Rowland, Ian J.; Goodman, Walter G.

    2016-01-01

    Non-invasive 3D magnetic resonance imaging techniques were used to investigate metamorphosis of the alimentary tract of Manduca sexta from the larval to the adult stage. The larval midgut contracts in volume immediately following cessation of feeding and then greatly enlarges during the late pharate pupal period. Magnetic resonance imaging revealed that the foregut and hindgut of the pharate pupa undergo ecdysis considerably earlier than the external exoskeleton. Expansion of air sacs in the early pupa and development of flight muscles several days later appear to orient the midgut into its adult position in the abdomen. The crop, an adult auxiliary storage organ, begins development as a dorsal outgrowth of the foregut. This coincides with a reported increase in pupal ecdysteroid titers. An outgrowth of the hindgut, the rectal sac, appears several days later and continues to expand until it nearly fills the dorsal half of the abdominal cavity. This development correlates with a second rise in pupal ecdysteroid titers. In the pharate pupa, the presence of paramagnetic species renders the silk glands hyperintense. PMID:27280776

  15. Development magnet for portable MRI device: Investigate skin cancer

    NASA Astrophysics Data System (ADS)

    Dogan, Nurcan

    2013-03-01

    Nuclear magnetic resonance (NMR) is well known from diagnostic medical imaging and analytical chemical spectroscopy. The sample is brought into the laboratory to be investigated with radio-waves inside stationary magnets. This paper describes a new approach useful to reduce the gradient strength of the magnetic field. Despite of the recent progress in magnet design, homogeneity of permenant magnet is still very limited. Fortunately for medical applications usually there is need in high-field homogeneity to obtain the high-resolution spectra that provide the detailed chemical shift and coupling-constant. In this work we discuss various permanent magnet design-without cooling system- for magnetic imaging. The magnet used for the present application consists of two units. The main unit is built from static magnet blocks and generates the main magnetic field. The second one is the shim unit. It consists of smaller movable magnets used to correct in a controlled manner the magnetic field generated by the main unit. By combining the two units, magnetic fields with defined spatial dependence can be generated with high accuracy. The performance of the magnet in terms of resolution and sensitivity is first evaluated and compared with conventional other magnets of higher gradient strength using phantoms of known geometry and relaxation times. After integration of magnet with spectrometer, Our new system is used to profile the structures of healty and unhealthy (cancer) human skins in vivo. To understand the contrast between the different skin type, the distribution of relaxation times T1 is spatially investigated.

  16. In vivo studies of brain development by magnetic resonance techniques.

    PubMed

    Inder, T E; Huppi, P S

    2000-01-01

    Understanding of the morphological development of the human brain has largely come from neuropathological studies obtained postmortem. Magnetic resonance (MR) techniques have recently allowed the provision of detailed structural, metabolic, and functional information in vivo on the human brain. These techniques have been utilized in studies from premature infants to adults and have provided invaluable data on the sequence of normal human brain development. This article will focus on MR techniques including conventional structural MR imaging techniques, quantitative morphometric MR techniques, diffusion weighted MR techniques, and MR spectroscopy. In order to understand the potential applications and limitations of MR techniques, relevant physical and biological principles for each of the MR techniques are first reviewed. This is followed by a review of the understanding of the sequence of normal brain development utilizing these techniques. MRDD Research Reviews 6:59-67, 2000. PMID:10899798

  17. Development and Evaluation of an Attractive Self-Marking Ovitrap to Measure Dispersal and Determine Skip Oviposition in Aedes albopictus (Diptera: Culicidae) Field Populations.

    PubMed

    Davis, Timothy J; Kaufman, Phillip E; Tatem, Andrew J; Hogsette, Jerome A; Kline, Daniel L

    2016-01-01

    Aedes albopictus (Skuse) is a container-breeding species with considerable public health importance. To date, Ae. albopictus oviposition behavior has been assessed in outdoor conditions, but only with laboratory-reared specimens. In outdoor large-cage and field studies, we used an attractive self-marking ovipositional device to assess Ae. albopictus skip oviposition behavior. In field studies, 37 wild Ae. albopictus that visited an attractive self-marking ovisite were subsequently captured at a sticky ovitrap within a 4-d period. Because the average Ae. albopictus gonotrophic period is 4.5-6 d, the wild-caught Ae. albopictus visited at least two oviposition sites within a single gonotrophic period. This provided field-based indirect evidence of skip oviposition. The mean distance traveled (MDT) during the 20-d evaluations ranged from 58 to 78 m. The maximum observed distance traveled was 149 m, which was the outer edge of our trapping ability. As populations of Ae. albopictus increased, the MDT during the 4- and 20-d post-marking period increased significantly. Additional observations of wild-marked and captured Aedes triseriatus (Say) are discussed. PMID:26534725

  18. Beyond initial attraction: physical attractiveness in newlywed marriage.

    PubMed

    McNulty, James K; Neff, Lisa A; Karney, Benjamin R

    2008-02-01

    Physical appearance plays a crucial role in shaping new relationships, but does it continue to affect established relationships, such as marriage? In the current study, the authors examined how observer ratings of each spouse's facial attractiveness and the difference between those ratings were associated with (a) observations of social support behavior and (b) reports of marital satisfaction. In contrast to the robust and almost universally positive effects of levels of attractiveness on new relationships, the only association between levels of attractiveness and the outcomes of these marriages was that attractive husbands were less satisfied. Further, in contrast to the importance of matched attractiveness to new relationships, similarity in attractiveness was unrelated to spouses' satisfaction and behavior. Instead, the relative difference between partners' levels of attractiveness appeared to be most important in predicting marital behavior, such that both spouses behaved more positively in relationships in which wives were more attractive than their husbands, but they behaved more negatively in relationships in which husbands were more attractive than their wives. These results highlight the importance of dyadic examinations of the effects of spouses' qualities on their marriages. PMID:18266540

  19. Magnetic particle imaging: current developments and future directions

    PubMed Central

    Panagiotopoulos, Nikolaos; Duschka, Robert L; Ahlborg, Mandy; Bringout, Gael; Debbeler, Christina; Graeser, Matthias; Kaethner, Christian; Lüdtke-Buzug, Kerstin; Medimagh, Hanne; Stelzner, Jan; Buzug, Thorsten M; Barkhausen, Jörg; Vogt, Florian M; Haegele, Julian

    2015-01-01

    Magnetic particle imaging (MPI) is a novel imaging method that was first proposed by Gleich and Weizenecker in 2005. Applying static and dynamic magnetic fields, MPI exploits the unique characteristics of superparamagnetic iron oxide nanoparticles (SPIONs). The SPIONs’ response allows a three-dimensional visualization of their distribution in space with a superb contrast, a very high temporal and good spatial resolution. Essentially, it is the SPIONs’ superparamagnetic characteristics, the fact that they are magnetically saturable, and the harmonic composition of the SPIONs’ response that make MPI possible at all. As SPIONs are the essential element of MPI, the development of customized nanoparticles is pursued with the greatest effort by many groups. Their objective is the creation of a SPION or a conglomerate of particles that will feature a much higher MPI performance than nanoparticles currently available commercially. A particle’s MPI performance and suitability is characterized by parameters such as the strength of its MPI signal, its biocompatibility, or its pharmacokinetics. Some of the most important adjuster bolts to tune them are the particles’ iron core and hydrodynamic diameter, their anisotropy, the composition of the particles’ suspension, and their coating. As a three-dimensional, real-time imaging modality that is free of ionizing radiation, MPI appears ideally suited for applications such as vascular imaging and interventions as well as cellular and targeted imaging. A number of different theories and technical approaches on the way to the actual implementation of the basic concept of MPI have been seen in the last few years. Research groups around the world are working on different scanner geometries, from closed bore systems to single-sided scanners, and use reconstruction methods that are either based on actual calibration measurements or on theoretical models. This review aims at giving an overview of current developments and

  20. Development of Pre-Preg Ceramic Insulation for Superconducting Magnets

    SciTech Connect

    Codell, D.E.; Fabian, P.E.

    2004-06-28

    A new pre-impregnated (pre-preg) ceramic-based electrical insulation system capable of surviving high superconductor reaction temperatures has been developed for use in superconducting magnets. The use of Nb3Sn superconductors holds great promise for increased magnet performance for high energy physics, fusion, and other applications. A robust, cost-effective manufacturing process is critical to the successful implementation of these coils. Due to its embrittlement after the high temperature reaction cycle, Nb3Sn cable is usually insulated and wound into the coil prior to heat treatment. An earlier ceramic-based insulation system, applied using wet-winding or vacuum impregnation, has been successfully used in the 'wind and react' fabrication process. Use of the new pre-preg system will further simplify the manufacturing process while improving control over the insulation properties. Pre-preg insulation offers several advantages including improved dimensional control of the insulation, controllable and uniform fiber to matrix ratio, and certainty that the insulation does not infiltrate the superconductor. This paper describes the pre-preg development process, processing properties, as well as insulation performance data at cryogenic temperatures.

  1. Development of Pre-Preg Ceramic Insulation for Superconducting Magnets

    NASA Astrophysics Data System (ADS)

    Codell, D. E.; Fabian, P. E.

    2004-06-01

    A new pre-impregnated (pre-preg) ceramic-based electrical insulation system capable of surviving high superconductor reaction temperatures has been developed for use in superconducting magnets. The use of Nb3Sn superconductors holds great promise for increased magnet performance for high energy physics, fusion, and other applications. A robust, cost-effective manufacturing process is critical to the successful implementation of these coils. Due to its embrittlement after the high temperature reaction cycle, Nb3Sn cable is usually insulated and wound into the coil prior to heat treatment. An earlier ceramic-based insulation system, applied using wet-winding or vacuum impregnation, has been successfully used in the "wind and react" fabrication process. Use of the new pre-preg system will further simplify the manufacturing process while improving control over the insulation properties. Pre-preg insulation offers several advantages including improved dimensional control of the insulation, controllable and uniform fiber to matrix ratio, and certainty that the insulation does not infiltrate the superconductor. This paper describes the pre-preg development process, processing properties, as well as insulation performance data at cryogenic temperatures.

  2. Magnetic Resonance Imaging Conditional Pacemakers: Rationale, Development and Future Directions

    PubMed Central

    Cronin, Edmond M; Wilkoff, Bruce L

    2012-01-01

    Pacemakers and other cardiac implantable electronic devices (CIEDs) have long been considered an absolute contraindication to magnetic resonance imaging (MRI), a crucial and growing imaging modality. In the last 20 years, protocols have been developed to allow MR scanning of CIED patients with a low complication rate. However, this practice has remained limited to a relatively small number of centers, and many pacemaker patients continue to be denied access to clinically indicated imaging. The introduction of MRI conditional pacemakers has provided a widely applicable and satisfactory solution to this problem. Here, the interactions of pacemakers with the MR environment, the results of MR scanning in patients with conventional CIEDs, the development and clinical experience with MRI conditional devices, and future directions are reviewed. PMID:23071382

  3. DEVELOPMENT OF A PRECISE MAGNETIC FIELD MEASUREMENT SYSTEM FOR FAST-CHANGING MAGNETIC FIELDS.

    SciTech Connect

    WANDERER,P.; ESCALLIER,J.; GANETIS,G.; JAIN,A.; LOUIE,W.; MARONE,A.; THOMAS,R.

    2003-06-15

    Several recent applications for fast ramped magnets have been found that require precise measurement of the time-dependent fields. In one instance, accelerator dipoles will be ramped at 1 T/sec, with measurements needed to the typical level of accuracy for accelerators, {Delta} B/B better than 0.01%. To meet this need, we have begun development of a system containing 16 stationary pickup windings that will be sampled at a high rate. It is hoped that harmonics through the decapole can be measured with this system. Precise measurement of the time-dependent harmonics requires that both the pickup windings and the voltmeters be nearly identical. To minimize costs, printed circuit boards are being used for the pickup windings and a combination of amplifiers and ADC's for voltmeters. In addition, new software must be developed for the analysis. The paper will present a status report on this work.

  4. Physical Attractiveness Stereotypes about Marriage: Attractiveness Matching Is Good.

    ERIC Educational Resources Information Center

    Sussman, Steve; And Others

    Previous research on physical attractiveness stereotypes about marriage have used stimulus individuals in isolation. To examine these attractiveness stereotypes using couples as targets, 72 college students (36 females, 36 males) rated eight photographs of four male-female couple types. Members of each couple were either matched (attractive…

  5. Development of miniature moving magnet cryocooler SX040

    NASA Astrophysics Data System (ADS)

    Rühlich, I.; Mai, M.; Rosenhagen, C.; Schreiter, A.; Möhl, C.

    2011-06-01

    State of the art high performance cooled IR systems need to have more than just excellent E/O performance. Minimum size weight and power (SWaP) are the design goals to meet our forces' mission requirements. Key enabler for minimum SWaP of IR imagers is the operation temperature of the focal plane array (FPA) employed. State of the art MCT or InAsSb nBn technology has the potential to rise the FPA temperature from 77 K to 130-150 K (high operation temperature HOT) depending on the specific cut-off wavelength. Using a HOT FPA will significantly lower SWaP and keep those parameters finally dominated by the employed cryocooler. Therefore compact high performance cryocoolers are mandatory. For highest MTTF life AIM developed its Flexure Bearing Moving Magnet product family "SF". Such coolers achieve more than 20000 h MTTF with Stirling type expander and more than 5 years MTTF life with Pulse Tube coldfinger (like for Space applications). To keep the high lifetime potential but to significantly improve SWaP AIM is developing its "SX" type cooler family. The new SX040 cooler incorporates a highly efficient dual piston Moving Magnet driving mechanism resulting in very compact compressor of less than 100mm length. The cooler's high lifetime is also achieved by placing the coils outside the helium vessel as usual for moving magnet motors. The mating ¼" expander is extremely compact with less than 63 mm length. This allows a total dewar length from optical window to expander warm end of less than 100 mm even for large cold shields. The cooler is optimized for HOT detectors with operating temperatures exceeding 95 K. While this kind of cooler is the perfect match for many applications, handheld sights or targeting devices for the dismounted soldier are even more challenging with respect to SWaP. AIM therefore started to develop an even smaller cooler type with single piston and balancer. This paper gives an overview on the development of this new compact cryocooler. Technical

  6. Facial Features: What Women Perceive as Attractive and What Men Consider Attractive.

    PubMed

    Muñoz-Reyes, José Antonio; Iglesias-Julios, Marta; Pita, Miguel; Turiegano, Enrique

    2015-01-01

    Attractiveness plays an important role in social exchange and in the ability to attract potential mates, especially for women. Several facial traits have been described as reliable indicators of attractiveness in women, but very few studies consider the influence of several measurements simultaneously. In addition, most studies consider just one of two assessments to directly measure attractiveness: either self-evaluation or men's ratings. We explored the relationship between these two estimators of attractiveness and a set of facial traits in a sample of 266 young Spanish women. These traits are: facial fluctuating asymmetry, facial averageness, facial sexual dimorphism, and facial maturity. We made use of the advantage of having recently developed methodologies that enabled us to measure these variables in real faces. We also controlled for three other widely used variables: age, body mass index and waist-to-hip ratio. The inclusion of many different variables allowed us to detect any possible interaction between the features described that could affect attractiveness perception. Our results show that facial fluctuating asymmetry is related both to self-perceived and male-rated attractiveness. Other facial traits are related only to one direct attractiveness measurement: facial averageness and facial maturity only affect men's ratings. Unmodified faces are closer to natural stimuli than are manipulated photographs, and therefore our results support the importance of employing unmodified faces to analyse the factors affecting attractiveness. We also discuss the relatively low equivalence between self-perceived and male-rated attractiveness and how various anthropometric traits are relevant to them in different ways. Finally, we highlight the need to perform integrated-variable studies to fully understand female attractiveness. PMID:26161954

  7. Facial Features: What Women Perceive as Attractive and What Men Consider Attractive

    PubMed Central

    Muñoz-Reyes, José Antonio; Iglesias-Julios, Marta; Pita, Miguel; Turiegano, Enrique

    2015-01-01

    Attractiveness plays an important role in social exchange and in the ability to attract potential mates, especially for women. Several facial traits have been described as reliable indicators of attractiveness in women, but very few studies consider the influence of several measurements simultaneously. In addition, most studies consider just one of two assessments to directly measure attractiveness: either self-evaluation or men's ratings. We explored the relationship between these two estimators of attractiveness and a set of facial traits in a sample of 266 young Spanish women. These traits are: facial fluctuating asymmetry, facial averageness, facial sexual dimorphism, and facial maturity. We made use of the advantage of having recently developed methodologies that enabled us to measure these variables in real faces. We also controlled for three other widely used variables: age, body mass index and waist-to-hip ratio. The inclusion of many different variables allowed us to detect any possible interaction between the features described that could affect attractiveness perception. Our results show that facial fluctuating asymmetry is related both to self-perceived and male-rated attractiveness. Other facial traits are related only to one direct attractiveness measurement: facial averageness and facial maturity only affect men's ratings. Unmodified faces are closer to natural stimuli than are manipulated photographs, and therefore our results support the importance of employing unmodified faces to analyse the factors affecting attractiveness. We also discuss the relatively low equivalence between self-perceived and male-rated attractiveness and how various anthropometric traits are relevant to them in different ways. Finally, we highlight the need to perform integrated-variable studies to fully understand female attractiveness. PMID:26161954

  8. Development of magnetic shape memory alloy actuators for a swashplateless helicopter rotor

    NASA Astrophysics Data System (ADS)

    Couch, Ronald Newton

    Actuator concepts utilizing NiMnGa, ferromagnetic shape memory alloy are investigated for potential use on a smart rotor for trailing edge flap actuation. With their high energy density, large dynamic stroke, and wide operating bandwidth, ferromagnetic shape memory alloys (FSMA) like NiMnGa, seem like attractive candidates for smart rotor actuators, potentially able to fulfill the requirements for both primary rotor control and vibration suppression. However, because of the recent discovery of the material, current experimental data and analytical tools are limited. To rectify these shortcomings, an extensive set of detailed experiments were conducted on samples of NiMnGa to characterize the response of the alloy for a wide variety of mechanical and magnetic loading conditions. Measurements of the material performance parameters such as power density, damping properties, magneto-mechanical coupling, and transduction efficiency were included. Once characterized, the experimental data were used to develop a series of analytical tools to predict the behavior of the material. A model, developed in parallel to thermal shape memory alloy models is proposed to predict the quasi-static stress-strain behavior. A simple, low frequency, parameter based model was also developed to predict the alloy's dynamic strain response. A method for developing conceptual actuators utilizing NiMnGa as the actuation element was proposed. This approach incorporates experimental data into a process that down-selects a series of possible actuator configurations to obtain a single configuration optimized for volumetric and weight considerations. The proposed actuator was designed to deliver 2 mm of stroke and 60 N of force at an actuation frequency of 50 Hz. However, to generate the 1.0 T magnetic field, the actuator mass was determined to be 2.8 kg and required a minimum of 320 Watts of power for operation. The mass of the NiMnGa element was only 18.3 g. It was concluded that although the Ni

  9. Development of cryogenic alpha spectrometers using metallic magnetic calorimeters

    NASA Astrophysics Data System (ADS)

    Ranitzsch, P. C.; Kempf, S.; Pabinger, A.; Pies, C.; Porst, J.-P.; Schäfer, S.; Fleischmann, A.; Gastaldo, L.; Enss, C.; Jang, Y. S.; Kim, I. H.; Kim, M. S.; Kim, Y. H.; Lee, J. S.; Lee, K. B.; Lee, M. K.; Lee, S. J.; Yoon, W. S.; Yuryev, Y. N.

    2011-10-01

    Cryogenic particle detectors have recently been adopted in radiation detection and measurement because of their high energy resolution. Many of these detectors have demonstrated energy resolutions better than the theoretical limit of semiconductor detectors. We report the development of a micro-fabricated magnetic calorimeter coupled to a large-area particle absorber. It is based on a planar, 1 mm 2 large paramagnetic temperature sensor made of sputtered Au:Er, which covers a superconducting meander-shaped pickup coil coupled to a low-noise dc-SQUID to monitor the magnetization of the sensor. A piece of gold foil of 2.5×2.5×0.07 mm 3 was glued to the Au:Er film to serve as an absorber for incident alpha particles. The detector performance was investigated with an 241Am source. The signal size comparison for alpha and gamma peaks with a large difference in energy demonstrated that the detector had good linear behavior. An energy resolution of 2.83±0.05 keV in FWHM was obtained for 5.5 MeV alpha particles.

  10. Iron-Nickel-Based SuperMagnets: Multiscale Development of L10 Materials for Rare Earth-Free Permanent Magnets

    SciTech Connect

    2012-01-01

    REACT Project: Northeastern University will develop bulk quantities of rare-earth-free permanent magnets with an iron-nickel crystal structure for use in the electric motors of renewable power generators and EVs. These materials could offer magnetic properties that are equivalent to today’s best commercial magnets, but with a significant cost reduction and diminished environmental impact. This iron-nickel crystal structure, which is only found naturally in meteorites and developed over billions of years in space, will be artificially synthesized by the Northeastern University team. Its material structure will be replicated with the assistance of alloying elements introduced to help it achieve superior magnetic properties. The ultimate goal of this project is to demonstrate bulk magnetic properties that can be fabricated at the industrial scale.

  11. Rock magnetism investigation of highly magnetic soil developed on calcareous rock in Yun-Gui Plateau, China: Evidence for pedogenic magnetic minerals

    NASA Astrophysics Data System (ADS)

    Lu, S. G.; Chen, D. J.; Wang, S. Y.; Liu, Y. D.

    2012-02-01

    Detailed rock-magnetic and pedological analyses were conducted on the highly magnetic soils developed on calcareous rocks in the Yun-Gui Plateau of west-southern China in order to characterize its particular magnetic characteristics and pedogenesis of magnetic minerals. The magnetic concentration and mineralogy in the soils were determined by rock magnetism, powder X-ray diffraction and high resolution transmission electron microscope (HRTEM) with the energy dispersive X-ray analysis (EDX). The highly magnetic soils contained characteristics of highly weathered soils with a hue of 2.5YR, dominantly gibbsite-sesquioxide mineralogy, low organic matter content and high clay and free iron (Fed) content. Soil magnetic susceptibility (χlf) ranged from 2000 × 10 - 8 to 6000 × 10 - 8 m 3 kg - 1 ; but in some layers it exceeded 6000 × 10 - 8 or 6500 × 10 - 8 m 3 kg - 1 , which was the highest magnetic soils so far found in the world. Magnetic measurements indicated that the frequency-dependent susceptibility (χlf - χhf) ranged from 210 × 10 - 8 to 720 × 10 - 8 m 3 kg - 1 , suggesting the presence of abundant ultrafine magnetic grains. High-temperature magnetization ( M- T) identified the magnetic carriers as maghemite and magnetite with a Curie point ( Tc) at about 230 °C and 580 °C, respectively. XRD patterns showed that the gibbsite and hematite were main clay minerals in these highly weathered soils. HRTEM/EDX analysis showed that the pedogenic nano-scale magnetite/maghemite were responsible for the high magnetic susceptibility value of the soil. These particles varied from 20 to 100 nm in size and exhibited well crystalline nanoparticles. Magnetic enhancement in the soil profile was due to increased concentration of pedogenic superparamagnetic (SP) ferrimagnetic minerals upon pedogenesis. This study provided a strong evidence for the evolution of pedogenic magnetic minerals in the soils formed on non-magnetic parent materials. The identification in magnetic

  12. Development of High-Field Permanent Magnetic Circuits for NMRI/MRI and Imaging on Mice

    PubMed Central

    Wang, Guangxin; Xie, Huantong; Hou, Shulian; Chen, Wei; Yang, Xiuhong

    2016-01-01

    The high-field permanent magnetic circuits of 1.2 T and 1.5 T with novel magnetic focusing and curved-surface correction are developed. The permanent magnetic circuit comprises a magnetic yoke, main magnetic steel, nonspherical curved-surface magnetic poles, plugging magnetic steel, and side magnetic steel. In this work, a novel shimming method is proposed for the effective correction of base magnetic field (B0) inhomogeneities, which is based on passive shimming on the telescope aspheric cutting, grinding, and fine processing technology of the nonspherical curved-surface magnetic poles and active shimming adding higher-order gradient coils. Meanwhile, the magnetic resonance imaging dedicated alloy with high-saturation magnetic field induction intensity and high electrical resistivity is developed, and nonspherical curved-surface magnetic poles which are made of the dedicated alloy have very good anti-eddy-current effect. In addition, the large temperature coefficient problem of permanent magnet can be effectively controlled by using a high quality temperature controller and deuterium external locking technique. Combining our patents such as gradient coil, RF coil, and integration computer software, two kinds of small animal Micro-MRI instruments are developed, by which the high quality MRI images of mice were obtained. PMID:27034951

  13. Development of High-Field Permanent Magnetic Circuits for NMRI/MRI and Imaging on Mice.

    PubMed

    Wang, Guangxin; Xie, Huantong; Hou, Shulian; Chen, Wei; Yang, Xiuhong

    2016-01-01

    The high-field permanent magnetic circuits of 1.2 T and 1.5 T with novel magnetic focusing and curved-surface correction are developed. The permanent magnetic circuit comprises a magnetic yoke, main magnetic steel, nonspherical curved-surface magnetic poles, plugging magnetic steel, and side magnetic steel. In this work, a novel shimming method is proposed for the effective correction of base magnetic field (B 0) inhomogeneities, which is based on passive shimming on the telescope aspheric cutting, grinding, and fine processing technology of the nonspherical curved-surface magnetic poles and active shimming adding higher-order gradient coils. Meanwhile, the magnetic resonance imaging dedicated alloy with high-saturation magnetic field induction intensity and high electrical resistivity is developed, and nonspherical curved-surface magnetic poles which are made of the dedicated alloy have very good anti-eddy-current effect. In addition, the large temperature coefficient problem of permanent magnet can be effectively controlled by using a high quality temperature controller and deuterium external locking technique. Combining our patents such as gradient coil, RF coil, and integration computer software, two kinds of small animal Micro-MRI instruments are developed, by which the high quality MRI images of mice were obtained. PMID:27034951

  14. Mathematical developments regarding the general theory of the Earth magnetism

    NASA Technical Reports Server (NTRS)

    Schmidt, A.

    1983-01-01

    A literature survey on the Earth's magnetic field, citing the works of Gauss, Erman-Petersen, Quintus Icilius and Neumayer is presented. The general formulas for the representation of the potential and components of the Earth's magnetic force are presented. An analytical representation of magnetic condition of the Earth based on observations is also made.

  15. Physical Attractiveness and Courtship Progress.

    ERIC Educational Resources Information Center

    White, Gregory L.

    1980-01-01

    Among college students who were casual or serious daters, greater relative attractiveness was positively correlated with greater relative availability of opposite-sexed friends and negatively correlated with worrying about partner's potential involvement with others. A 9-month follow-up revealed that similarity of attractiveness was predictive of…

  16. Physical Attractiveness and Interpersonal Influence

    ERIC Educational Resources Information Center

    Dion, Karen K.; Stein, Steven

    1978-01-01

    Examines the hypothesis that attractive individuals should be more successful with opposite-sex peers but less successful with same-sex peers than unattractive individuals. Also investigates the influence strategies employed by persons differing in attractiveness since nothing is currently known about the actual behavior exhibited by attractive…

  17. Physical Attractiveness and Counseling Skills.

    ERIC Educational Resources Information Center

    Vargas, Alice M.; Borkowski, John G.

    1982-01-01

    Searched for interaction between quality of counseling skills (presence or absence of empathy, genuineness, and positive regard) and physical attractiveness as determinants of counseling effectiveness. Attractiveness influenced perceived effectiveness of counselor's skill. Analyses of expectancy data revealed that only with good skills did…

  18. Personality Mediators of Interpersonal Attraction.

    ERIC Educational Resources Information Center

    Johnson, Charles D.; And Others

    The current study was an examination of the effect of personality variables on the relationship between attitude disagreement and attraction. Attraction was measured in a neutral situation, designed to maximize any existing affective predispositions toward attitude agreement-disagreements. Subjects were placed in an ambiguous face-to-face…

  19. Observer-Based Magnetic Bearing Controller Developed for Aerospace Flywheels

    NASA Technical Reports Server (NTRS)

    Le, Dzu K.; Provenza, Andrew J.

    2002-01-01

    A prototype of a versatile, observer-based magnetic bearing controller for aerospace flywheels was successfully developed and demonstrated on a magnetic bearing test rig (see the photograph) and an actual flywheel module. The objective of this development included a fast, yet low risk, control development process, and a robust, high-performance controller for a large variety of flywheels. This required a good system model, an efficient development procedure, and a model-based controller that addressed the key problems associated with flywheel and bearing imbalance, sensor error, and vibration. The model used in this control development and tuning procedure included the flexible rotor dynamics and motor-induced vibrations. Such a model was essential for low-risk scheduling of speed-dependent control parameters and for reliable evaluation of novel control strategies. The successfully tested control prototype utilized an extended Kalman filter to estimate the true rotor principal-axis motion from the raw sensor position feedback. For control refinement, the extended Kalman filter also estimated and eliminated the combined effects of mass-imbalance and sensor runouts from the input data. A key advantage of the design based on the extended Kalman filter is its ability to accurately estimate both the rotor's principal-axis position and gyroscopic rates with the least amount of phase lag. This is important for control parameter scheduling to dampen the gyroscopic motions. Because of large uncertainties in the magnetic bearing and imbalance characteristics, this state-estimation scheme alone is insufficient for containing the rotor motion within the desired 1-mil excursion radius. A nonlinear gain adjustment based on an estimation of the principal-axis orbit size was needed to provide a coarse (nonoptimal), but robust, control of the orbit growth. Control current minimization was achieved with a (steepest gradient) search of synchronous errors in the principal

  20. Development of motion capture system using alternating magnetic field

    NASA Astrophysics Data System (ADS)

    Kumagai, Masaaki; Akamatsu, Kazuyoshi

    2005-12-01

    Motion capture systems are widely used for virtual reality, motion acquisition for medical researches, for humanoid robots, for video games, etc. Several types of them have been developed and used for applications considering their advantages and restrictions. Another type of motion capture system that uses alternating magnetic field is proposed in this paper. The system uses a field exciting coil that covers measuring area and a pickup coil attached to target. First, six alternating fields are generated simultaneously in measuring area, and signals are induced on pickup coils according to attitude and position of it. These signals are processed to extract amplitude of exciting components, and state of the pickup coil is calculated from those components. It can detect attitude and displacement of target with high resolution and fast response speed. The principles of detection and brief experimental results are described.

  1. Physical attractiveness stereotype and memory.

    PubMed

    Rohner, Jean-Christophe; Rasmussen, Anders

    2011-08-01

    Three experiments examined explicit and implicit memory for information that is congruent with the physical attractiveness stereotype (i.e. attractive-positive and unattractive-negative) and information that is incongruent with the physical attractiveness stereotype (i.e. attractive-negative and unattractive-positive). Measures of explicit recognition sensitivity and implicit discriminability revealed a memorial advantage for congruent compared to incongruent information, as evident from hit and false alarm rates and reaction times, respectively. Measures of explicit memory showed a recognition bias toward congruent compared to incongruent information, where participants tended to call congruent information old, independently of whether the information had been shown previously or not. This recognition bias was unrelated to reports of subjective confidence in retrieval. The present findings shed light on the cognitive mechanisms that might mediate discriminatory behavior towards physically attractive and physically unattractive individuals. PMID:21255024

  2. Magnetically operated check valve

    NASA Technical Reports Server (NTRS)

    Morris, Brian G. (Inventor); Bozeman, Richard J., Jr. (Inventor)

    1994-01-01

    A magnetically operated check valve is disclosed. The valve is comprised of a valve body and a movable poppet disposed therein. A magnet attracts the poppet to hold the valve shut until the force of fluid flow through the valve overcomes the magnetic attraction and moves the poppet to an unseated, open position. The poppet and magnet are configured and disposed to trap a magnetically attracted particulate and prevent it from flowing to a valve seating region.

  3. Magnetic flux annihilation and the development of magnetic field depletions in the sectored heliosheath

    NASA Astrophysics Data System (ADS)

    Drake, J. F.; Swisdak, M.; Opher, M.

    2015-12-01

    The dynamics of magnetic reconnection in the sectored heliosheath isexplored with the goal of identifying signatures that can be comparedwith Voyager observations. Simulations now include much more realisticinitial conditions, including unequal magnetic fluxes in adjacentsectors and very high β. Large numbers of small magnetic islandsform early but rapidly coalesce to sector-size structures. Thelate-time magnetic structure of the sector zone differs greatly fromthat obtained in earlier simulations. Bands of unreconnected azimuthalmagnetic flux thread through the simulation domain separating regionsof depleted magnetic field strength. The depletion regions have radialscale sizes somewhat greater than the initial sector width. Theboundaries of the magnetic depletions are sharp and reveal littlechange in the direction of B. The characteristic minima of thedepletions are one third of the initial magnetic field strength. Atlate time surviving magnetic islands are widely spaced and occur inpairs. Cuts across the domain in the radial direction reveal mostlyunipolar flux except when a cut crosses one of the remnant magneticislands. This unusual late time magnetic structure is generic resultof reconnection in a high β system. The magnetic depletionsexhibit many of the properties of ``proton boundary layers'' seen inthe Voyager 1 magnetic field data. The simulations suggest that significant flux loss should take place in the heliosheath, which is consistent with Voyager measurements. The long periods of unipolar fluxseen by Voyager 1 prior to crossing the heliopause likely results fromthe annihilation of the sectors rather than an exit from the sectorzone.

  4. Development of high-vacuum planar magnetron sputtering using an advanced magnetic field geometry

    SciTech Connect

    Ohno, Takahiro; Yagyu, Daisuke; Saito, Shigeru Ohno, Yasunori; Itoh, Masatoshi; Uhara, Yoshio; Miura, Tsutomu; Nakano, Hirofumi

    2015-11-15

    A permanent magnet in a new magnetic field geometry (namely, with the magnetization in the radial direction) was fabricated and used for high-vacuum planar magnetron sputtering using Penning discharge. Because of the development of this magnet, the discharge current and deposition rate were increased two to three times in comparison with the values attainable with a magnet in the conventional geometry. This improvement was because the available space for effective discharge of the energetic electrons for the ionization increased because the magnetic field distribution increased in both the axial and radial directions of discharge.

  5. Progress Toward Attractive Stellarators

    SciTech Connect

    Neilson, G H; Brown, T G; Gates, D A; Lu, K P; Zarnstorff, M C; Boozer, A H; Harris, J H; Meneghini, O; Mynick, H E; Pomphrey, N; Reiman, A H; Xanthopoulos, P

    2011-01-05

    The quasi-axisymmetric stellarator (QAS) concept offers a promising path to a more compact stellarator reactor, closer in linear dimensions to tokamak reactors than previous stellarator designs. Concept improvements are needed, however, to make it more maintainable and more compatible with high plant availability. Using the ARIES-CS design as a starting point, compact stellarator designs with improved maintenance characteristics have been developed. While the ARIES-CS features a through-the-port maintenance scheme, we have investigated configuration changes to enable a sector-maintenance approach, as envisioned for example in ARIES AT. Three approaches are reported. The first is to make tradeoffs within the QAS design space, giving greater emphasis to maintainability criteria. The second approach is to improve the optimization tools to more accurately and efficiently target the physics properties of importance. The third is to employ a hybrid coil topology, so that the plasma shaping functions of the main coils are shared more optimally, either with passive conductors made of high-temperature superconductor or with local compensation coils, allowing the main coils to become simpler. Optimization tools are being improved to test these approaches.

  6. Attracting men to vasectomy.

    PubMed

    Finger, W R

    1998-01-01

    There is far less information available for men about vasectomy than there is available for women about comparable contraceptive services. Also, men do not have medical check-ups on a regular basis, and therefore have less contact with medical practitioners during which vasectomy could otherwise be discussed. Vasectomy needs to be promoted in order for men to learn about and accept it as their contraceptive method of choice. To that end, Marie Stopes International (MSI) launches a vasectomy promotion campaign annually which includes advertising in local newspapers and upon billboards at football stadiums. The campaigns use light-hearted and bold ideas, with some shock value. This approach helps to relax men who otherwise tend to be wary of both the surgical procedure and subsequent consequences of vasectomy. Prevailing social norms should, however, guide the content of promotional campaigns. The UK is one of only a few countries in the world where about the same proportions of men and women use sterilization; 16% of men and 15% of women have been sterilized. A MSI campaign in the UK which began during fall 1997 prompted an increase in the number of inquiries about vasectomy at the Marie Stopes Vasectomy Clinic. Promotional campaigns in developing countries have also been successful. It is also important that campaigns be put in the larger context of promoting all contraceptive methods. PMID:12293534

  7. Design and development of a new magnetic sensor for stress measurements

    NASA Astrophysics Data System (ADS)

    Aggelopoulos, S.

    2016-03-01

    This paper describes the design and the development of a new magnetic sensor for stress measurements using the magnetic Barkhausen noise and the magnetic permeability techniques in ferromagnetic steels. Both techniques together, become an important nondestructive technique, due to its exceptional material and stress characterization capabilities. The correlation of the two methods was investigated. Conclusions were derived based on the experimental results.

  8. Facial attractiveness and self-esteem in adolescence.

    PubMed

    Mares, Suzanne H W; de Leeuw, Rebecca N H; Scholte, Ron H J; Engels, Rutger C M E

    2010-01-01

    Facial attractiveness has been associated with many (social) advantages in life, like greater popularity, acceptance, and social competence. Because social evaluations and acceptance are important factors contributing to self-esteem (SE), we hypothesized that high levels of attractiveness would be related to increased levels of SE. To test this assumption, 230 adolescents from two age groups (13 and 15 years) were surveyed annually for 5 years. A latent growth curve model was used to model the influence of facial attractiveness on the development of SE over time. Results showed that younger adolescents with higher levels of attractiveness had lower levels of SE at baseline. Attractiveness was not found to be a significant predictor in explaining the development of SE over time. These findings indicate that attractive children are more likely to have lower levels of SE when they enter early adolescence compared to their less attractive counterparts. PMID:20706916

  9. Development of Cellular Magnetic Dipoles in Magnetotactic Bacteria

    PubMed Central

    Faivre, Damien; Fischer, Anna; Garcia-Rubio, Inés; Mastrogiacomo, Giovanni; Gehring, Andreas U.

    2010-01-01

    Magnetotactic bacteria benefit from their ability to form cellular magnetic dipoles by assembling stable single-domain ferromagnetic particles in chains as a means to navigate along Earth's magnetic field lines on their way to favorable habitats. We studied the assembly of nanosized membrane-encapsulated magnetite particles (magnetosomes) by ferromagnetic resonance spectroscopy using Magnetospirillum gryphiswaldense cultured in a time-resolved experimental setting. The spectroscopic data show that 1), magnetic particle growth is not synchronized; 2), the increase in particle numbers is insufficient to build up cellular magnetic dipoles; and 3), dipoles of assembled magnetosome blocks occur when the first magnetite particles reach a stable single-domain state. These stable single-domain particles can act as magnetic docks to stabilize the remaining and/or newly nucleated superparamagnetic particles in their adjacencies. We postulate that docking is a key mechanism for building the functional cellular magnetic dipole, which in turn is required for magnetotaxis in bacteria. PMID:20713012

  10. Development of three-dimensional printing system for magnetic elastomer with control of magnetic anisotropy in the structure

    NASA Astrophysics Data System (ADS)

    Tsumori, Fujio; Kawanishi, Hidenori; Kudo, Kentaro; Osada, Toshiko; Miura, Hideshi

    2016-06-01

    In this paper, we report on a new system of three-dimensional (3D) printing for a magnetic elastomer that contains magnetic particles. Not only can we fabricate a three-dimensional structure, but we can also control the magnetically anisotropic property of each position in the structure using the present technique. Our new system employed photocurable poly(dimethylsiloxane) (PDMS) as the base material so that a method similar to a conventional 3D printing process with photolithography can be used. A magnetic powder was mixed with photocurable PDMS, and particle chain clusters were obtained by applying a magnetic field during the curing process. These chain clusters provide an anisotropic property in each part of the printed structure. We show some results of preliminary experiments and 3D printed samples in this paper. If the fabricated structure was placed under an applied magnetic field, each chain cluster will cause the rotational moment to be along the magnetic flux line, which can deform a soft matrix body. This deformation can be used as a magnetic actuator for the structure. Variable deformable structures could be developed using the present method.

  11. Recent developments in a wind tunnel magnetic balance.

    NASA Technical Reports Server (NTRS)

    Stephens, T.; Covert, E. E.; Vlajinac, M.; Gilliam, G. D.

    1972-01-01

    A functional description of a prototype six component magnetic balance system for wind tunnel application is presented. The relationship of forces and moments on a ferromagnetic body to applied magnetic fields and gradients is shown. The method of producing the required fields in the prototype balance, its magnet arrangement and its performance are discussed. Aerodynamic data obtained with this balance on several model geometries are presented and compared with wind tunnel and ballistic range results.

  12. The dynamical crossover in attractive colloidal systems

    SciTech Connect

    Mallamace, Francesco; Corsaro, Carmelo; Stanley, H. Eugene; Mallamace, Domenico; Chen, Sow-Hsin

    2013-12-07

    We study the dynamical arrest in an adhesive hard-sphere colloidal system. We examine a micellar suspension of the Pluronic-L64 surfactant in the temperature (T) and volume fraction (ϕ) phase diagram. According to mode-coupling theory (MCT), this system is characterized by a cusp-like singularity and two glassy phases: an attractive glass (AG) phase and a repulsive glass (RG) phase. The T − ϕ phase diagram of this system as confirmed by a previous series of scattering data also exhibits a Percolation Threshold (PT) line, a reentrant behavior (AG-liquid-RG), and a glass-to-glass transition. The AG phase can be generated out of the liquid phase by using T and ϕ as control parameters. We utilize viscosity and nuclear magnetic resonance (NMR) techniques. NMR data confirm all the characteristic properties of the colloidal system phase diagram and give evidence of the onset of a fractal-like percolating structure at a precise threshold. The MCT scaling laws used to study the shear viscosity as a function of ϕ and T show in both cases a fragile-to-strong liquid glass-forming dynamic crossover (FSC) located near the percolation threshold where the clustering process is fully developed. These results suggest a larger thermodynamic generality for this phenomenon, which is usually studied only as a function of the temperature. We also find that the critical values of the control parameters, coincident with the PT line, define the locus of the FSC. In the region between the FSC and the glass transition lines the system dynamics are dominated by clustering effects. We thus demonstrate that it is possible, using the conceptual framework provided by extended mode-coupling theory, to describe the way a system approaches dynamic arrest, taking into account both cage and hopping effects.

  13. The dynamical crossover in attractive colloidal systems

    NASA Astrophysics Data System (ADS)

    Mallamace, Francesco; Corsaro, Carmelo; Stanley, H. Eugene; Mallamace, Domenico; Chen, Sow-Hsin

    2013-12-01

    We study the dynamical arrest in an adhesive hard-sphere colloidal system. We examine a micellar suspension of the Pluronic-L64 surfactant in the temperature (T) and volume fraction (ϕ) phase diagram. According to mode-coupling theory (MCT), this system is characterized by a cusp-like singularity and two glassy phases: an attractive glass (AG) phase and a repulsive glass (RG) phase. The T - ϕ phase diagram of this system as confirmed by a previous series of scattering data also exhibits a Percolation Threshold (PT) line, a reentrant behavior (AG-liquid-RG), and a glass-to-glass transition. The AG phase can be generated out of the liquid phase by using T and ϕ as control parameters. We utilize viscosity and nuclear magnetic resonance (NMR) techniques. NMR data confirm all the characteristic properties of the colloidal system phase diagram and give evidence of the onset of a fractal-like percolating structure at a precise threshold. The MCT scaling laws used to study the shear viscosity as a function of ϕ and T show in both cases a fragile-to-strong liquid glass-forming dynamic crossover (FSC) located near the percolation threshold where the clustering process is fully developed. These results suggest a larger thermodynamic generality for this phenomenon, which is usually studied only as a function of the temperature. We also find that the critical values of the control parameters, coincident with the PT line, define the locus of the FSC. In the region between the FSC and the glass transition lines the system dynamics are dominated by clustering effects. We thus demonstrate that it is possible, using the conceptual framework provided by extended mode-coupling theory, to describe the way a system approaches dynamic arrest, taking into account both cage and hopping effects.

  14. The dynamical crossover in attractive colloidal systems.

    PubMed

    Mallamace, Francesco; Corsaro, Carmelo; Stanley, H Eugene; Mallamace, Domenico; Chen, Sow-Hsin

    2013-12-01

    We study the dynamical arrest in an adhesive hard-sphere colloidal system. We examine a micellar suspension of the Pluronic-L64 surfactant in the temperature (T) and volume fraction (φ) phase diagram. According to mode-coupling theory (MCT), this system is characterized by a cusp-like singularity and two glassy phases: an attractive glass (AG) phase and a repulsive glass (RG) phase. The T - φ phase diagram of this system as confirmed by a previous series of scattering data also exhibits a Percolation Threshold (PT) line, a reentrant behavior (AG-liquid-RG), and a glass-to-glass transition. The AG phase can be generated out of the liquid phase by using T and φ as control parameters. We utilize viscosity and nuclear magnetic resonance (NMR) techniques. NMR data confirm all the characteristic properties of the colloidal system phase diagram and give evidence of the onset of a fractal-like percolating structure at a precise threshold. The MCT scaling laws used to study the shear viscosity as a function of φ and T show in both cases a fragile-to-strong liquid glass-forming dynamic crossover (FSC) located near the percolation threshold where the clustering process is fully developed. These results suggest a larger thermodynamic generality for this phenomenon, which is usually studied only as a function of the temperature. We also find that the critical values of the control parameters, coincident with the PT line, define the locus of the FSC. In the region between the FSC and the glass transition lines the system dynamics are dominated by clustering effects. We thus demonstrate that it is possible, using the conceptual framework provided by extended mode-coupling theory, to describe the way a system approaches dynamic arrest, taking into account both cage and hopping effects. PMID:24320386

  15. Attracting Clients to Service-Oriented Programs.

    ERIC Educational Resources Information Center

    Disney, Diane M.

    One of a series of manuals developed by the Home and Community-Based Career Education Project, the outreach component publication describes how the project went about attracting clients for its adult vocational counseling services. Sections include: creating a publicity campaign, using an advertising agency, creating products for the mass media,…

  16. Depression, Schizophrenia, and Social Attraction.

    ERIC Educational Resources Information Center

    Boswell, Philip C.; Murray, Edward J.

    1981-01-01

    Compared the dysphoric mood induction and attraction that subjects reported after a vicarious experience with a depressed patient and a comparable experience with a schizophrenic patient. Results showed similar arousal of dysphoric mood and rejection for both patients. (RC)

  17. Attraction between hydrated hydrophilic surfaces

    NASA Astrophysics Data System (ADS)

    Kanduč, Matej; Schneck, Emanuel; Netz, Roland R.

    2014-08-01

    According to common knowledge, hydrophilic surfaces repel via hydration forces while hydrophobic surfaces attract, but mounting experimental evidence suggests that also hydrophilic surfaces can attract. Using all-atom molecular dynamics simulations at prescribed water chemical potential we study the crossover from hydration repulsion to hydrophobic attraction for planar polar surfaces of varying stiffness and hydrogen-bonding capability. Rescaling the partial charges of the polar surface groups, we cover the complete spectrum from very hydrophobic surfaces (characterized by contact angles θ ≃ 135°) to hydrophilic surfaces exhibiting complete wetting (θ = 0°). Indeed, for a finite range θadh < θ < 90°, we find a regime where hydrophilic surfaces attract at sub-nanometer separation and stably adhere without intervening water. The adhesive contact angle θadh depends on surface type and lies in the range 65° < θadh < 80°, in good agreement with experiments. Analysis of the total number of hydrogen bonds (HBs) formed by water and surface groups rationalizes this crossover between hydration repulsion and hydrophilic attraction in terms of a subtle balance: Highly polar surfaces repel because of strongly bound hydration water, less polar hydrophilic surfaces attract because water-water HBs are preferred over surface-water HBs. Such solvent reorganization forces presumably underlie also other important phenomena, such as selective ion adsorption to interfaces as well as ion pair formation.

  18. Planning and Developing Magnet Schools: Experiences and Observations.

    ERIC Educational Resources Information Center

    Blank, Rolf K., Ed.; Messier, Paul R., Ed.

    This document consists of nine papers which discuss the planning and design, implementation and maintenance, and evaluation of magnet schools. They are based on practical experience with magnet schools, which first appeared in the early 1970s. By 1982, the movement had grown to include more than 1,200 schools in 140 urban school districts, and the…

  19. The LHC magnet system and its status of development

    NASA Technical Reports Server (NTRS)

    Bona, Maurizio; Perin, Romeo; Vlogaert, Jos

    1995-01-01

    CERN is preparing for the construction of a new high energy accelerator/collider, the Large Hadron Collider (LHC). This new facility will mainly consist of two superconducting magnetic beam channels, 27 km long, to be installed in the existing LEP tunnel. The magnetic system comprises about 1200 twin-aperture dipoles, 13.145 m long, with an operational field of 8.65 T, about 600 quadrupoles, 3 m long, and a very large number of other superconducting magnetic components. A general description of the system is given together with the main features of the design of the regular lattice magnets. The paper also describes the present state of the magnet R & D program. Results from short model work, as well as from full scale prototypes will be presented, including the recently tested 10 m long full-scale prototype dipole manufactured in industry.

  20. Magnetic Micro/Nano Structures for Biological Manipulation

    NASA Astrophysics Data System (ADS)

    Huang, Chen-Yu; Hsieh, Teng-Fu; Chang, Wei-Chieh; Yeh, Kun-Chieh; Hsu, Ming-Shinn; Chang, Ching-Ray; Chen, Jiann-Yeu; Wei, Zung-Hang

    2016-05-01

    Biomanipulation based on micro/nano structures is an attractive approach for biotechnology. To manipulate biological systems by magnetic forces, the magnetic labeling technology utilized magnetic nanoparticles (MNPs) as a common rule. Ferrofluid, well-dispersed MNPs, can be used for magnetic modification of the surface or as molds to form organized microstructures. For magnetic-based micro/nano structures, different methods to modulate magnetic field at the microscale have been developed. Specifically, this review focused on a new strategy which uses the concept of micromagnetism of patterned magnetic thin film with specific domain walls configurations to generate stable magnetic poles for cell patterning.

  1. Attraction of pinewood nematode to endoparasitic nematophagous fungus Esteya vermicola.

    PubMed

    Wang, Chun Yan; Wang, Zhen; Fang, Zhe Ming; Zhang, Dong Liang; Gu, Li Juan; Liu, Lei; Sung, Chang Keun

    2010-05-01

    The investigations on attraction of nematodes to nematophagous fungi have mostly dealt with the nematode-trapping species. Esteya vermicola is the endoparasitic fungus of pinewood nematode (PWN) with high infection activity. In the present study, the attraction of PWNs to E. vermicola was investigated. It was confirmed that the living mycelia and exudative substances of E. vermicola were attractive to PWN. Compared with the nematode-trapping fungus A. brochopaga as well as nematode-feeding fungus B. cinerea, E. vermicola showed the significantly strongest attraction ability to nematode. It therefore appeared that the attraction ability reflects the dependence of the fungi on nematodes for nutrients. Furthermore, a new method was developed and used in the study to confirm the effect of volatile substances for the attraction of nematode to fungi. The results suggested that the attractive substances were consisted of avolatile exudative and volatile diffusing compounds. PMID:20012046

  2. Development of imaging bolometers for magnetic fusion reactors (invited).

    PubMed

    Peterson, Byron J; Parchamy, Homaira; Ashikawa, Naoko; Kawashima, Hisato; Konoshima, Shigeru; Kostryukov, Artem Yu; Miroshnikov, Igor V; Seo, Dongcheol; Omori, T

    2008-10-01

    Imaging bolometers utilize an infrared (IR) video camera to measure the change in temperature of a thin foil exposed to the plasma radiation, thereby avoiding the risks of conventional resistive bolometers related to electric cabling and vacuum feedthroughs in a reactor environment. A prototype of the IR imaging video bolometer (IRVB) has been installed and operated on the JT-60U tokamak demonstrating its applicability to a reactor environment and its ability to provide two-dimensional measurements of the radiation emissivity in a poloidal cross section. In this paper we review this development and present the first results of an upgraded version of this IRVB on JT-60U. This upgrade utilizes a state-of-the-art IR camera (FLIR/Indigo Phoenix-InSb) (3-5 microm, 256 x 360 pixels, 345 Hz, 11 mK) mounted in a neutron/gamma/magnetic shield behind a 3.6 m IR periscope consisting of CaF(2) optics and an aluminum mirror. The IRVB foil is 7 cm x 9 cm x 5 microm tantalum. A noise equivalent power density of 300 microW/cm(2) is achieved with 40 x 24 channels and a time response of 10 ms or 23 microW/cm(2) for 16 x 12 channels and a time response of 33 ms, which is 30 times better than the previous version of the IRVB on JT-60U. PMID:19044463

  3. Development of a Hybrid Magnetic Resonance and Ultrasound Imaging System

    PubMed Central

    Sherwood, Victoria; Rivens, Ian; Collins, David J.; Leach, Martin O.; ter Haar, Gail R.

    2014-01-01

    A system which allows magnetic resonance (MR) and ultrasound (US) image data to be acquired simultaneously has been developed. B-mode and Doppler US were performed inside the bore of a clinical 1.5 T MRI scanner using a clinical 1–4 MHz US transducer with an 8-metre cable. Susceptibility artefacts and RF noise were introduced into MR images by the US imaging system. RF noise was minimised by using aluminium foil to shield the transducer. A study of MR and B-mode US image signal-to-noise ratio (SNR) as a function of transducer-phantom separation was performed using a gel phantom. This revealed that a 4 cm separation between the phantom surface and the transducer was sufficient to minimise the effect of the susceptibility artefact in MR images. MR-US imaging was demonstrated in vivo with the aid of a 2 mm VeroWhite 3D-printed spherical target placed over the thigh muscle of a rat. The target allowed single-point registration of MR and US images in the axial plane to be performed. The system was subsequently demonstrated as a tool for the targeting and visualisation of high intensity focused ultrasound exposure in the rat thigh muscle. PMID:25177702

  4. Development of imaging bolometers for magnetic fusion reactors (invited)

    SciTech Connect

    Peterson, Byron J.; Parchamy, Homaira; Ashikawa, Naoko; Kawashima, Hisato; Konoshima, Shigeru; Kostryukov, Artem Yu.; Miroshnikov, Igor V.; Seo, Dongcheol; Omori, T.

    2008-10-15

    Imaging bolometers utilize an infrared (IR) video camera to measure the change in temperature of a thin foil exposed to the plasma radiation, thereby avoiding the risks of conventional resistive bolometers related to electric cabling and vacuum feedthroughs in a reactor environment. A prototype of the IR imaging video bolometer (IRVB) has been installed and operated on the JT-60U tokamak demonstrating its applicability to a reactor environment and its ability to provide two-dimensional measurements of the radiation emissivity in a poloidal cross section. In this paper we review this development and present the first results of an upgraded version of this IRVB on JT-60U. This upgrade utilizes a state-of-the-art IR camera (FLIR/Indigo Phoenix-InSb) (3-5 {mu}m, 256x360 pixels, 345 Hz, 11 mK) mounted in a neutron/gamma/magnetic shield behind a 3.6 m IR periscope consisting of CaF{sub 2} optics and an aluminum mirror. The IRVB foil is 7 cmx9 cmx5 {mu}m tantalum. A noise equivalent power density of 300 {mu}W/cm{sup 2} is achieved with 40x24 channels and a time response of 10 ms or 23 {mu}W/cm{sup 2} for 16x12 channels and a time response of 33 ms, which is 30 times better than the previous version of the IRVB on JT-60U.

  5. Linear-Quadratic-Gaussian Regulator Developed for a Magnetic Bearing

    NASA Technical Reports Server (NTRS)

    Choi, Benjamin B.

    2002-01-01

    Linear-Quadratic-Gaussian (LQG) control is a modern state-space technique for designing optimal dynamic regulators. It enables us to trade off regulation performance and control effort, and to take into account process and measurement noise. The Structural Mechanics and Dynamics Branch at the NASA Glenn Research Center has developed an LQG control for a fault-tolerant magnetic bearing suspension rig to optimize system performance and to reduce the sensor and processing noise. The LQG regulator consists of an optimal state-feedback gain and a Kalman state estimator. The first design step is to seek a state-feedback law that minimizes the cost function of regulation performance, which is measured by a quadratic performance criterion with user-specified weighting matrices, and to define the tradeoff between regulation performance and control effort. The next design step is to derive a state estimator using a Kalman filter because the optimal state feedback cannot be implemented without full state measurement. Since the Kalman filter is an optimal estimator when dealing with Gaussian white noise, it minimizes the asymptotic covariance of the estimation error.

  6. Development of a hybrid magnetic resonance and ultrasound imaging system.

    PubMed

    Sherwood, Victoria; Civale, John; Rivens, Ian; Collins, David J; Leach, Martin O; ter Haar, Gail R

    2014-01-01

    A system which allows magnetic resonance (MR) and ultrasound (US) image data to be acquired simultaneously has been developed. B-mode and Doppler US were performed inside the bore of a clinical 1.5 T MRI scanner using a clinical 1-4 MHz US transducer with an 8-metre cable. Susceptibility artefacts and RF noise were introduced into MR images by the US imaging system. RF noise was minimised by using aluminium foil to shield the transducer. A study of MR and B-mode US image signal-to-noise ratio (SNR) as a function of transducer-phantom separation was performed using a gel phantom. This revealed that a 4 cm separation between the phantom surface and the transducer was sufficient to minimise the effect of the susceptibility artefact in MR images. MR-US imaging was demonstrated in vivo with the aid of a 2 mm VeroWhite 3D-printed spherical target placed over the thigh muscle of a rat. The target allowed single-point registration of MR and US images in the axial plane to be performed. The system was subsequently demonstrated as a tool for the targeting and visualisation of high intensity focused ultrasound exposure in the rat thigh muscle. PMID:25177702

  7. Developments of superconducting motor with YBCO bulk magnets

    NASA Astrophysics Data System (ADS)

    Hirakawa, M.; Inadama, S.; Kikukawa, K.; Suzuki, E.; Nakasima, H.

    2003-10-01

    We designed and manufactured a superconducting motor with YBCO superconductive bulk magnets. The motor, equipped with YBCO bulks as trapped field magnets and copper coils as armature windings, is an eight-poled synchronous motor of outer rotor type. The bulks are cooled to around 30 K by a refrigerator. This cooling operation is simpler than the other methods like cooling by liquid nitrogen. This paper presents the construction of the motor, the method of cooling bulks and the method of activating YBCO bulk magnets.

  8. Developing hyperpolarized krypton-83 for nuclear magnetic resonance spectroscopy and magnetic resonance imaging

    NASA Astrophysics Data System (ADS)

    Cleveland, Zackary I.

    This dissertation discusses the production of highly nonequilibrium nuclear spin polarization, referred to as hyperpolarization or hp, in the nuclear spin I = 9/2 noble gas isotope krypton-83 using spin exchange optical pumping (SEOP). This nonequilibrium polarization yields nuclear magnetic resonance (NMR) signals that are enhanced three or more orders of magnitude above those of thermally polarized krypton and enables experiments that would otherwise be impossible. Krypton-83 possesses a nuclear electric quadrupole moment that dominates the longitudinal (T1) relaxation due to coupling of the quadrupole moment to fluctuating electric field gradients generated by distortions to the spherical symmetry of the electronic environment. Relaxation slows polarization buildup and limits the maximum signal intensity but makes krypton-83 a sensitive probe of its environment. The gas-phase krypton-83 longitudinal relaxation rate increases linearly with total gas density due to binary collisions. Density independent relaxation, caused by the formation of krypton-krypton van der Waals molecules and surface adsorption, also contributes to the observed rate. Buffer gases suppress van der Waals molecule mediated relaxation by breaking apart the weakly bound krypton dimers. Surface relaxation is gas composition independent and therefore more difficult to suppress. However, this relaxation mechanism makes hp krypton-83 sensitive to important surface properties including surface-to-volume ratio, surface chemistry, and surface temperature. The presence of surfaces with high krypton adsorption affinities (i.e. hydrophobic surfaces) accelerates the relaxation times and can produce T1 contrast in hp krypton-83 magnetic resonance imaging (MRI). Tobacco smoke deposited on surfaces generates strong T1 contrast allowing the observation of smoke deposition with spatial resolution. Conversely, water adsorption on surfaces significantly lengths the T1 times due competitive surface adsorption

  9. Development of a temperature-variable magnetic resonance imaging system using a 1.0 T yokeless permanent magnet

    NASA Astrophysics Data System (ADS)

    Terada, Y.; Tamada, D.; Kose, K.

    2011-10-01

    A temperature variable magnetic resonance imaging (MRI) system has been developed using a 1.0 T permanent magnet. A permanent magnet, gradient coils, radiofrequency coil, and shim coil were installed in a temperature variable thermostatic bath. First, the variation in the magnetic field inhomogeneity with temperature was measured. The inhomogeneity has a specific spatial symmetry, which scales linearly with temperature, and a single-channel shim coil was designed to compensate for the inhomogeneity. The inhomogeneity was drastically reduced by shimming over a wide range of temperature from -5 °C to 45 °C. MR images of an okra pod acquired at different temperatures demonstrated the high potential of the system for visualizing thermally sensitive properties.

  10. Intention of Students in Less Developed Cities in China to Opt for Undergraduate Education Abroad: Does This Vary as Their Perceptions of the Attractions of Overseas Study Change?

    ERIC Educational Resources Information Center

    Hung, Fan-sing

    2010-01-01

    This study is based on a survey in 2007 of 12,961 senior secondary final year students in seven major cities in China, and shows that students in less developed cities manifest a stronger intention to study abroad than students in better off cities, controlling for students' other demographic characteristics and their major perceived attractions…

  11. Gelation and phase separation of attractive colloids

    NASA Astrophysics Data System (ADS)

    Lu, Peter James

    2008-07-01

    I present several scientific and technical contributions in this thesis. I demonstrate that the gelation of spherical particles with isotropic, short-range attractive interactions is initiated by spinodal decomposition, a thermodynamic instability that triggers the formation of clusters that span and dynamically arrest to create a gel. This simple, universal gelation picture does not depend on microscopic system-specific details---thus broadly describing any particle system with short-range attractions---and suggests that gelation, often considered a purely kinetic phenomenon, is in fact a direct consequence of equilibrium liquid-gas phase separation. I also demonstrate that spherical particles with isotropic attractive interactions exhibit a stable phase---a fluid of particle clusters---that persists on experimental timescales even in the absence of any long-range Coulombic charge repulsion; this contrasts some expectations based on simulation and theory. I describe a new capability I created by integrating accelerated image processing software that I wrote into a high-speed confocal microscope system that I developed: active target-locking, the ability to follow freely-moving complex objects within a microscope sample, even as they change size, shape, and orientation---in real time. Finally, I report continuous, month-long observations of near-critical spinodal decomposition of colloids with isotropic attractions, aboard the International Space Station. I also include detailed descriptions, with examples and illustrations, of the tools and techniques that I have developed to produce these results.

  12. Development of a miniaturized, light-weight magnetic sector for a field-portable mass spectrograph

    NASA Technical Reports Server (NTRS)

    Sinha, M. P.; Tomassian, A. D.

    1991-01-01

    A miniaturized, lightweight magnetic sector for a focal plane mass spectrograph (Mattauch-Herzog design) has been designed and fabricated by using a new high-energy-product magnet material (Nd-B-Fe alloy) and a high permeability magnet yoke material (V-Co-Fe alloy). The magnetic sector weighs less than 10 kg, has a focal plane of 5.1 cm in length, and covers a nominal mass range of 40-240 amu. Such a magnetic sector, in conjunction with an array detector and a short microbore capillary column, is well suited for the development of a field-portable gas chromatograph-mass spectrometer instrument of high performance.

  13. Further Development of an Optimal Design Approach Applied to Axial Magnetic Bearings

    NASA Technical Reports Server (NTRS)

    Bloodgood, V. Dale, Jr.; Groom, Nelson J.; Britcher, Colin P.

    2000-01-01

    Classical design methods involved in magnetic bearings and magnetic suspension systems have always had their limitations. Because of this, the overall effectiveness of a design has always relied heavily on the skill and experience of the individual designer. This paper combines two approaches that have been developed to aid the accuracy and efficiency of magnetostatic design. The first approach integrates classical magnetic circuit theory with modern optimization theory to increase design efficiency. The second approach uses loss factors to increase the accuracy of classical magnetic circuit theory. As an example, an axial magnetic thrust bearing is designed for minimum power.

  14. Vocal attractiveness increases by averaging.

    PubMed

    Bruckert, Laetitia; Bestelmeyer, Patricia; Latinus, Marianne; Rouger, Julien; Charest, Ian; Rousselet, Guillaume A; Kawahara, Hideki; Belin, Pascal

    2010-01-26

    Vocal attractiveness has a profound influence on listeners-a bias known as the "what sounds beautiful is good" vocal attractiveness stereotype [1]-with tangible impact on a voice owner's success at mating, job applications, and/or elections. The prevailing view holds that attractive voices are those that signal desirable attributes in a potential mate [2-4]-e.g., lower pitch in male voices. However, this account does not explain our preferences in more general social contexts in which voices of both genders are evaluated. Here we show that averaging voices via auditory morphing [5] results in more attractive voices, irrespective of the speaker's or listener's gender. Moreover, we show that this phenomenon is largely explained by two independent by-products of averaging: a smoother voice texture (reduced aperiodicities) and a greater similarity in pitch and timbre with the average of all voices (reduced "distance to mean"). These results provide the first evidence for a phenomenon of vocal attractiveness increases by averaging, analogous to a well-established effect of facial averaging [6, 7]. They highlight prototype-based coding [8] as a central feature of voice perception, emphasizing the similarity in the mechanisms of face and voice perception. PMID:20129047

  15. Development of an active magnetic regenerator for space applications

    NASA Astrophysics Data System (ADS)

    Chen, Weibo

    2014-07-01

    This paper discusses the design of a micromachined regenerator in an Active Magnetic Regenerative Refrigeration (AMRR) system for space applications. The AMRR system is designed to provide continuous remote/distributed cooling at about 2 K and reject heat at temperatures of about 15 K. This paper first discusses the general thermal and fluid performance requirements for an AMRR regenerator, a unique structured bed configuration that enables the regenerator to meet these requirements, and its thermal and fluid performance based on numerical analyses. The paper then discusses the general design consideration for the magnetic field driving the regenerator for optimal thermal performance, and the analysis processes to optimize the variation rate of the magnetic field in an actual superconducting magnet during the isothermal processes of the AMRR cycle to enhance the performance of an actual regenerator. The paper finally presents the thermal performance of the regenerator from such iterative design optimization processes.

  16. Research developing closed loop roll control for magnetic balance systems

    NASA Technical Reports Server (NTRS)

    Covert, E. E.; Haldeman, C. W.

    1981-01-01

    Computer inputs were interfaced to the magnetic balance outputs to provide computer position control and data acquisition. The use of parameter identification of a means of determining dynamic characteristics was investigated. The thyraton and motor generator power supplies for the pitch and yaw degrees of freedom were repaired. Topics covered include: choice of a method for handling dynamic system data; applications to the magnetic balance; the computer interface; and wind tunnel tests, results, and error analysis.

  17. Developments in deep brain stimulation using time dependent magnetic fields

    SciTech Connect

    Crowther, L.J.; Nlebedim, I.C.; Jiles, D.C.

    2012-03-07

    The effect of head model complexity upon the strength of field in different brain regions for transcranial magnetic stimulation (TMS) has been investigated. Experimental measurements were used to verify the validity of magnetic field calculations and induced electric field calculations for three 3D human head models of varying complexity. Results show the inability for simplified head models to accurately determine the site of high fields that lead to neuronal stimulation and highlight the necessity for realistic head modeling for TMS applications.

  18. The historical development of the magnetic method in exploration

    USGS Publications Warehouse

    Nabighian, M.N.; Grauch, V.J.S.; Hansen, R.O.; LaFehr, T.R.; Li, Y.; Peirce, J.W.; Phillips, J.D.; Ruder, M.E.

    2005-01-01

    The magnetic method, perhaps the oldest of geophysical exploration techniques, blossomed after the advent of airborne surveys in World War II. With improvements in instrumentation, navigation, and platform compensation, it is now possible to map the entire crustal section at a variety of scales, from strongly magnetic basement at regional scale to weakly magnetic sedimentary contacts at local scale. Methods of data filtering, display, and interpretation have also advanced, especially with the availability of low-cost, high-performance personal computers and color raster graphics. The magnetic method is the primary exploration tool in the search for minerals. In other arenas, the magnetic method has evolved from its sole use for mapping basement structure to include a wide range of new applications, such as locating intrasedimentary faults, defining subtle lithologic contacts, mapping salt domes in weakly magnetic sediments, and better defining targets through 3D inversion. These new applications have increased the method's utility in all realms of exploration - in the search for minerals, oil and gas, geothermal resources, and groundwater, and for a variety of other purposes such as natural hazards assessment, mapping impact structures, and engineering and environmental studies. ?? 2005 Society of Exploration Geophysicists. All rights reserved.

  19. Aversion and attraction through olfaction

    PubMed Central

    Li, Qian; Liberles, Stephen D.

    2015-01-01

    Sensory cues that predict reward or punishment are fundamental drivers of animal behavior. For example, attractive odors of palatable food or a potential mate predict reward while aversive odors of pathogen-laced food or a predator predict punishment. Aversive and attractive odors can be detected by intermingled sensory neurons that express highly related olfactory receptors and display similar central projections. These findings raise basic questions of how innate odor valence is extracted from olfactory circuits, how such circuits are developmentally endowed and modulated by state, and the relationship between innate and learned odor responses. Here, we review odors, receptors, and neural circuits associated with stimulus valence, discussing salient principles derived from studies on nematodes, insects, and vertebrates. Understanding the organization of neural circuitry that mediates odor aversion and attraction will provide key insights into how the brain functions. PMID:25649823

  20. Effective writing that attracts patients.

    PubMed

    Baum, Neil

    2015-01-01

    Doctors today not only must communicate verbally, they must also realize that the written word is important to their ability to connect with the patients that they already have and also to attract new patients. Doctors will be expected to write blogs, to create content for their Web sites, to write articles for local publications, and even to learn to express themselves in 140 characters or less (i.e., Twitter). This article presents 10 rules for selecting the right words to enhance your communication with existing patients and potentially to attract new patients to your practice. PMID:26062324

  1. Development of Wind-and-React Bi-2212 Accelerator Magnet Technology

    SciTech Connect

    Godeke, A.; Cheng, D.; Dietderich, D. R.; English, C. D.; Felice, H.; Hannaford, C. R.; Prestemon, S. O.; Sabbi, G.; Scanlan, R. M.; Hikichi, Y.; Nishioka, J.; Hasegawa, T.

    2007-08-28

    We report on the progress in our R&D program, targeted to develop the technology for the application of Bi2Sr2CaCu2Ox (Bi-2212) in accelerator magnets. The program uses subscale coils, wound from insulated cables, to study suitable materials, heat treatment homogeneity, stability, and effects of magnetic field and thermal and electro-magnetic loads. We have addressed material and reaction related issues and report on the fabrication, heat treatment, and analysis of subscale Bi-2212 coils. Such coils can carry a current on the order of 5000 A and generate, in various support structures, magnetic fields from 2.6 to 9.9 T. Successful coils are therefore targeted towards a hybrid Nb3Sn-HTS magnet which will demonstrate the feasibility of Bi-2212 for accelerator magnets, and open a new magnetic field realm, beyond what is achievable with Nb3Sn.

  2. Nanoscale size effect of magnetic nanocrystals and their utilization for cancer diagnosis via magnetic resonance imaging.

    PubMed

    Jun, Young-Wook; Huh, Yong-Min; Choi, Jin-Sil; Lee, Jae-Hyun; Song, Ho-Taek; Kim, Sungjun; Yoon, Sarah; Kim, Kyung-Sup; Shin, Jeon-Soo; Suh, Jin-Suck; Cheon, Jinwoo

    2005-04-27

    Since the use of magnetic nanocrystals as probes for biomedical system is attractive, it is important to develop optimal synthetic protocols for high-quality magnetic nanocrystals and to have the systematic understanding of their nanoscale properties. Here we present the development of a synthetically controlled magnetic nanocrystal model system that correlates the nanoscale tunabilities in terms of size, magnetism, and induced nuclear spin relaxation processes. This system further led to the development of high-performance nanocrystal-antibody probe systems for the diagnosis of breast cancer cells via magnetic resonance imaging. PMID:15839639

  3. Development of a Magnetic Attachment Method for Bionic Eye Applications.

    PubMed

    Fox, Kate; Meffin, Hamish; Burns, Owen; Abbott, Carla J; Allen, Penelope J; Opie, Nicholas L; McGowan, Ceara; Yeoh, Jonathan; Ahnood, Arman; Luu, Chi D; Cicione, Rosemary; Saunders, Alexia L; McPhedran, Michelle; Cardamone, Lisa; Villalobos, Joel; Garrett, David J; Nayagam, David A X; Apollo, Nicholas V; Ganesan, Kumaravelu; Shivdasani, Mohit N; Stacey, Alastair; Escudie, Mathilde; Lichter, Samantha; Shepherd, Robert K; Prawer, Steven

    2016-03-01

    Successful visual prostheses require stable, long-term attachment. Epiretinal prostheses, in particular, require attachment methods to fix the prosthesis onto the retina. The most common method is fixation with a retinal tack; however, tacks cause retinal trauma, and surgical proficiency is important to ensure optimal placement of the prosthesis near the macula. Accordingly, alternate attachment methods are required. In this study, we detail a novel method of magnetic attachment for an epiretinal prosthesis using two prostheses components positioned on opposing sides of the retina. The magnetic attachment technique was piloted in a feline animal model (chronic, nonrecovery implantation). We also detail a new method to reliably control the magnet coupling force using heat. It was found that the force exerted upon the tissue that separates the two components could be minimized as the measured force is proportionately smaller at the working distance. We thus detail, for the first time, a surgical method using customized magnets to position and affix an epiretinal prosthesis on the retina. The position of the epiretinal prosthesis is reliable, and its location on the retina is accurately controlled by the placement of a secondary magnet in the suprachoroidal location. The electrode position above the retina is less than 50 microns at the center of the device, although there were pressure points seen at the two edges due to curvature misalignment. The degree of retinal compression found in this study was unacceptably high; nevertheless, the normal structure of the retina remained intact under the electrodes. PMID:26416723

  4. Magnetic particle hyperthermia: nanoparticle magnetism and materials development for cancer therapy

    NASA Astrophysics Data System (ADS)

    Hergt, Rudolf; Dutz, Silvio; Müller, Robert; Zeisberger, Matthias

    2006-09-01

    Loss processes in magnetic nanoparticles are discussed with respect to optimization of the specific loss power (SLP) for application in tumour hyperthermia. Several types of magnetic iron oxide nanoparticles representative for different preparation methods (wet chemical precipitation, grinding, bacterial synthesis, magnetic size fractionation) are the subject of a comparative study of structural and magnetic properties. Since the specific loss power useful for hyperthermia is restricted by serious limitations of the alternating field amplitude and frequency, the effects of the latter are investigated experimentally in detail. The dependence of the SLP on the mean particle size is studied over a broad size range from superparamagnetic up to multidomain particles, and guidelines for achieving large SLP under the constraints valid for the field parameters are derived. Particles with the mean size of 18 nm having a narrow size distribution proved particularly useful. In particular, very high heating power may be delivered by bacterial magnetosomes, the best sample of which showed nearly 1 kW g-1 at 410 kHz and 10 kA m-1. This value may even be exceeded by metallic magnetic particles, as indicated by measurements on cobalt particles.

  5. Attracting Birds to Your Backyard.

    ERIC Educational Resources Information Center

    Joyce, Brian

    1994-01-01

    Discusses methods for drawing birds to outdoor education areas, including the use of wild and native vegetation. Lists specific garden plants suitable for attracting birds in each season. Includes a guide to commercial bird seed and instructions for building homemade birdfeeders and nestboxes. (LZ)

  6. Attractiveness and Influence in Counseling

    ERIC Educational Resources Information Center

    Schmidt, Lyle D.; Strong, Stanley R.

    1971-01-01

    The results showed that in spite of violently different feelings about (or descriptions of) the roles, the subjects were equally influenced by them. This suggests that social attractiveness may not be important when the client's problems require expert opinion and knowledge. (Author/CG(

  7. Functional Similarity and Interpersonal Attraction.

    ERIC Educational Resources Information Center

    Neimeyer, Greg J.; Neimeyer, Robert A.

    1981-01-01

    Students participated in dyadic disclosure exercises over a five-week period. Results indicated members of high functional similarity dyads evidenced greater attraction to one another than did members of low functional similarity dyads. "Friendship" pairs of male undergraduates displayed greater functional similarity than did "nominal" pairs from…

  8. Development of superconducting high gradient magnetic separation system for highly viscous fluid for practical use

    NASA Astrophysics Data System (ADS)

    Hayashi, S.; Mishima, F.; Akiyama, Y.; Nishijima, S.

    2011-11-01

    In the industrial plants processing highly viscous fluid such as foods or industrial products, it is necessary to remove the metallic wear debris originating from pipe in manufacturing line which triggers quality loss. In this study, we developed a high gradient magnetic separation (HGMS) system which consists of superconducting magnet to remove the metallic wear debris. The magnetic separation experiment and the particle trajectory simulation were conducted with polyvinyl alcohol (PVA) as a model material (viscosity coefficient was 10 Pa s, which is 10,000 times higher than that in water). In order to develop a magnetic separation system for practical use, the particle trajectory simulation by using solenoidal superconducting magnet was conducted, and the possibility of the magnetic separation for removing ferromagnetic stainless steel (SUS) particles in highly viscous fluid of 10 Pa s was indicated. Based on the results, the number of filters to obtain required separation efficiency was examined to design the practical separation system.

  9. Development of closed loop roll control for magnetic balance systems

    NASA Technical Reports Server (NTRS)

    Covert, E. E.; Haldeman, C. W.; Ramohalli, G.; Way, P.

    1982-01-01

    This research was undertaken with the goal of demonstrating closed loop control of the roll degree of freedom on the NASA prototype magnetic suspension and balance system at the MIT Aerophysics Laboratory, thus, showing feasibility for a roll control system for any large magnetic balance system which might be built in the future. During the research under this grant, study was directed toward the several areas of torque generation, position sensing, model construction and control system design. These effects were then integrated to produce successful closed loop operation of the analogue roll control system. This experience indicated the desirability of microprocessor control for the angular degrees of freedom.

  10. Recent developments in semiprocessed cold rolled magnetic lamination steel

    NASA Astrophysics Data System (ADS)

    Hilinski, E. J.

    2006-09-01

    Over the past 10 years the magnetic property performance of semi-processed cold rolled magnetic lamination steels in North America have approached those of nonoriented, semi-processed silicon steel. This improvement was accomplished via higher alloy levels in conjunction with hot band annealing. New temper rolling strategies can produce weakly oriented steels tailored to specific applications, such as small transformers used in fluorescent lighting ballasts. Recently, production trials for 0.0138 in product cold rolled on tin mills has been undertaken. Efforts to further improve properties through a better understanding of texture control and via implementation of new production processes, such as thin slab or strip casting, continue.

  11. Fatal attraction: sexually cannibalistic invaders attract naive native mantids

    PubMed Central

    Fea, Murray P.; Stanley, Margaret C.; Holwell, Gregory I.

    2013-01-01

    Overlap in the form of sexual signals such as pheromones raises the possibility of reproductive interference by invasive species on similar, yet naive native species. Here, we test the potential for reproductive interference through heterospecific mate attraction and subsequent predation of males by females of a sexually cannibalistic invasive praying mantis. Miomantis caffra is invasive in New Zealand, where it is widely considered to be displacing the only native mantis species, Orthodera novaezealandiae, and yet mechanisms behind this displacement are unknown. We demonstrate that native males are more attracted to the chemical cues of introduced females than those of conspecific females. Heterospecific pairings also resulted in a high degree of mortality for native males. This provides evidence for a mechanism behind displacement that has until now been undetected and highlights the potential for reproductive interference to greatly influence the impact of an invasive species. PMID:24284560

  12. Fatal attraction: sexually cannibalistic invaders attract naive native mantids.

    PubMed

    Fea, Murray P; Stanley, Margaret C; Holwell, Gregory I

    2013-01-01

    Overlap in the form of sexual signals such as pheromones raises the possibility of reproductive interference by invasive species on similar, yet naive native species. Here, we test the potential for reproductive interference through heterospecific mate attraction and subsequent predation of males by females of a sexually cannibalistic invasive praying mantis. Miomantis caffra is invasive in New Zealand, where it is widely considered to be displacing the only native mantis species, Orthodera novaezealandiae, and yet mechanisms behind this displacement are unknown. We demonstrate that native males are more attracted to the chemical cues of introduced females than those of conspecific females. Heterospecific pairings also resulted in a high degree of mortality for native males. This provides evidence for a mechanism behind displacement that has until now been undetected and highlights the potential for reproductive interference to greatly influence the impact of an invasive species. PMID:24284560

  13. Development of MnBi permanent magnet: Neutron diffraction of MnBi powder

    NASA Astrophysics Data System (ADS)

    Cui, J.; Choi, J. P.; Li, G.; Polikarpov, E.; Darsell, J.; Kramer, M. J.; Zarkevich, N. A.; Wang, L. L.; Johnson, D. D.; Marinescu, M.; Huang, Q. Z.; Wu, H.; Vuong, N. V.; Liu, J. P.

    2014-05-01

    MnBi attracts great attention in recent years for its great potential as permanent magnet materials. MnBi phase is difficult to obtain because of the rather drastic peritectic reaction between Mn and Bi. In this paper, we report our effort on synthesizing high purity MnBi compound using conventional powder metallurgical approaches. Neutron diffraction was carried out to investigate the crystal and nuclear structure of the obtained powder. The result shows that the purity of the obtained powder is about 91 wt. % at 300 K, and the magnetic moment of the Mn atom in MnBi lattice is 4.424 and 4.013 μB at 50 K and 300 K, respectively.

  14. Development of MnBi permanent magnet: Neutron diffraction of MnBi powder

    SciTech Connect

    Cui, J. Choi, J. P.; Li, G.; Polikarpov, E.; Darsell, J.; Kramer, M. J.; Zarkevich, N. A.; Wang, L. L.; Johnson, D. D.; Marinescu, M.; Huang, Q. Z.; Wu, H.; Vuong, N. V.; Liu, J. P.

    2014-05-07

    MnBi attracts great attention in recent years for its great potential as permanent magnet materials. MnBi phase is difficult to obtain because of the rather drastic peritectic reaction between Mn and Bi. In this paper, we report our effort on synthesizing high purity MnBi compound using conventional powder metallurgical approaches. Neutron diffraction was carried out to investigate the crystal and nuclear structure of the obtained powder. The result shows that the purity of the obtained powder is about 91 wt. % at 300 K, and the magnetic moment of the Mn atom in MnBi lattice is 4.424 and 4.013 μ{sub B} at 50 K and 300 K, respectively.

  15. Development of MnBi permanent magnet: Neutron diffraction of MnBi powder

    SciTech Connect

    Cui, J.; Choi, J. P.; Li, G.; Polikarpov, E.; Darsell, J.; Kramer, M. J.; Zarkevich, N. A.; Wang, L. L.; Johnson, D. D.; Marinescu, M.; Huang, Q. Z.; Wu, H.; Vuong, N. V.; Liu, J. P.

    2014-05-07

    MnBi attracts great attention in recent years for its great potential as permanent magnet materials. MnBi phase is difficult to obtain because of the rather drastic peritectic reaction between Mn and Bi. In this paper, we report our effort on synthesizing high purity MnBi compound using conventional powder metallurgical approaches. Neutron diffraction was carried out to investigate the crystal and nuclear structure of the obtained powder. The result shows that the purity of the obtained powder is about 91 wt. % at 300 K, and the magnetic moment of the Mn atom in MnBi lattice is 4.424 and 4.013 μB at 50 K and 300 K, respectively.

  16. Development of MnBi permanent magnet: Neutron diffraction of MnBi powder

    SciTech Connect

    Cui, J; Choi, JP; Li, G; Polikarpov, E; Darsell, J; Kramer, MJ; Zarkevich, NA; Wang, LL; Johnson, DD; Marinescu, M; Huang, QZ; Wu, H; Vuong, NV; Liu, JP

    2014-05-07

    MnBi attracts great attention in recent years for its great potential as permanent magnet materials. MnBi phase is difficult to obtain because of the rather drastic peritectic reaction between Mn and Bi. In this paper, we report our effort on synthesizing high purity MnBi compound using conventional powder metallurgical approaches. Neutron diffraction was carried out to investigate the crystal and nuclear structure of the obtained powder. The result shows that the purity of the obtained powder is about 91 wt. % at 300 K, and the magnetic moment of the Mn atom in MnBi lattice is 4.424 and 4.013 mu(B) at 50 K and 300 K, respectively. (C) 2014 AIP Publishing LLC.

  17. Development of MnBi permanent magnet: neutron diffraction of MnBi powder

    SciTech Connect

    Cui, Jun; Choi, Jung-Pyung; Li, Guosheng; Polikarpov, Evgueni; Darsell, Jens T.; Kramer, Matthew J.; Zarkevich, Nikolai; Wang, L. L.; Johnson, D. D.; Marinescu, Melania; Huang, Qingzhen; Wu, Hui; Vuong, Nguyen V.; Liu, J.Ping

    2014-03-05

    MnBi attracts great attention in recent years for its great potential as permanent magnet materials. MnBi phase is difficult to obtain because of the rather drastic peritectic reaction between Mn and Bi. In this paper, we report our effort on synthesizing high purity MnBi compound using conventional powder metallurgical approaches. Neutron diffraction was carried out to investigate the crystal and nuclear structure of the obtained power. The result shows that the purity of the obtained powder is about 91wt.% at 300K, and the magnetic moment of the Mn atom in MnBi lattice is 4.424 and 4.013 μB at 50 K and 300 K respectively.

  18. DEVELOPMENT OF CHICKEN EMBRYOS IN A PULSED MAGNETIC FIELD

    EPA Science Inventory

    Six independent experiments of common design were performed in laboratories in Canada, Spain, Sweden, and the United States of America. ertilized eggs of domestic chickens were incubated as controls or in a pulsed magnetic field (PMF); embryos were then examined for developmental...

  19. Development of superconducting magnet for high-field MR systems in China

    NASA Astrophysics Data System (ADS)

    Wang, Zanming; van Oort, Johannes M.; Zou, Mark X.

    2012-11-01

    In this paper we describe the development of superconducting magnets for high-field Magnetic Resonance Imaging (MRI) by various businesses and institutions in China. As the Chinese MR market rapidly expands, many foreign and domestic companies and research institutions are joining the race to meet the burgeoning demand by developing key MRI components for various magnetic field configurations. After providing a brief introduction to research on MRI superconducting magnets that dates back to the 1980s, the first large-bore 1.5 T superconducting magnet with 50-cm DSV for whole-body MRI - successfully developed and manufactured by AllTech Medical Systems in Chengdu, China-is presented and its specifications are described.

  20. Inflection Points in Magnetic Resonance Imaging Technology-35 Years of Collaborative Research and Development.

    PubMed

    Wood, Michael L; Griswold, Mark A; Henkelman, Mark; Hennig, Jürgen

    2015-09-01

    The technology for clinical magnetic resonance imaging (MRI) has advanced with remarkable speed and in such a manner reflecting the influence of 3 forces-collaboration between disciplines, collaboration between academia and industry, and the enabling of software applications by hardware. The forces are evident in the key developments from the past and emerging trends for the future highlighted in this review article. These developments are associated with MRI system attributes, such as wider, shorter, and stronger magnets; specialty magnets and hybrid devices; k space; and the notion that magnetic field gradients perform a Fourier transform on the spatial distribution of magnetization, phased-array coils and parallel imaging, the user interface, the wide range of contrast possible, and applications that exploit motion-induced phase shifts. An attempt is made to show connections between these developments and how the 3 forces mentioned previously will continue to shape the technology used so productively in clinical MRI. PMID:25985463

  1. Facial attractiveness: evolutionary based research

    PubMed Central

    Little, Anthony C.; Jones, Benedict C.; DeBruine, Lisa M.

    2011-01-01

    Face preferences affect a diverse range of critical social outcomes, from mate choices and decisions about platonic relationships to hiring decisions and decisions about social exchange. Firstly, we review the facial characteristics that influence attractiveness judgements of faces (e.g. symmetry, sexually dimorphic shape cues, averageness, skin colour/texture and cues to personality) and then review several important sources of individual differences in face preferences (e.g. hormone levels and fertility, own attractiveness and personality, visual experience, familiarity and imprinting, social learning). The research relating to these issues highlights flexible, sophisticated systems that support and promote adaptive responses to faces that appear to function to maximize the benefits of both our mate choices and more general decisions about other types of social partners. PMID:21536551

  2. Fingertip aura and interpersonal attraction.

    PubMed

    Murstein, B I; Hadjolian, S E

    1977-06-01

    Concluding from our survey of the literature that fingertip auras (Kirlian effect) might be associated with interpersonal attraction, four hypotheses were advanced to test this assertion. It was hypothesized that individuals would respond with bigger auras to (1) opposite-sex photographers as compared to same-sex photographers, (2) to seductive opposite-sex photographers as opposed to normally behaving opposite-sex photographers, (3) to opposite-sex unknown peers as opposed to same-sex unknown peers, and (4) to liked as opposed to disliked same-sex persons. All hypotheses except (2) were supported. The second hypothesis was significant in a direction contrary to hypothesis. Fingertip auras are seen as a promising measurement device in the study of interpersonal attraction. PMID:16367230

  3. The attraction of Brazil nuts

    NASA Astrophysics Data System (ADS)

    Sanders, D. A.; Swift, M. R.; Bowley, R. M.; King, P. J.

    2006-02-01

    Simulations of intruder particles in a vertically vibrated granular bed suggest that neutrally-buoyant intruders are attracted to one another (Phys. Rev. Lett., 93 (2004) 208002). The simulations, however, ignore important physical effects such as friction and convection which are known to influence intruder behaviour. Here, we present experimental evidence for this intruder-intruder interaction, obtained by monitoring the position of neutrally-buoyant metallic disks in a vibrated bed of glass spheres. An effective long-range attraction is shown to exist between a pair of intruders for a range of driving conditions. If further intruder particles are added, a tightly bound cluster of intruders can form. These results highlight the difficulty of retaining well-mixed granular beds under vertical vibration.

  4. Facial attractiveness: evolutionary based research.

    PubMed

    Little, Anthony C; Jones, Benedict C; DeBruine, Lisa M

    2011-06-12

    Face preferences affect a diverse range of critical social outcomes, from mate choices and decisions about platonic relationships to hiring decisions and decisions about social exchange. Firstly, we review the facial characteristics that influence attractiveness judgements of faces (e.g. symmetry, sexually dimorphic shape cues, averageness, skin colour/texture and cues to personality) and then review several important sources of individual differences in face preferences (e.g. hormone levels and fertility, own attractiveness and personality, visual experience, familiarity and imprinting, social learning). The research relating to these issues highlights flexible, sophisticated systems that support and promote adaptive responses to faces that appear to function to maximize the benefits of both our mate choices and more general decisions about other types of social partners. PMID:21536551

  5. Physical Attractiveness and Health in Western Societies: A Review

    ERIC Educational Resources Information Center

    Weeden, Jason; Sabini, John

    2005-01-01

    Evidence from developed Western societies is reviewed for the claims that (a) physical attractiveness judgments are substantially based on body size and shape, symmetry, sex-typical hormonal markers, and other specific cues and (b) physical attractiveness and these cues substantially predict health. Among the cues that the authors review, only…

  6. Can Pensions Help Attract Teachers?

    ERIC Educational Resources Information Center

    Kimball, Steven M.; Heneman, Herbert G.,III; Kellor, Eileen M.

    2005-01-01

    Every year there is a substantial flow of people into teaching roles as entrants or as movers from one school to another. Each such move involves attraction of the person to the job. Data for 1999-2000 reveal several important findings about teacher staffing. In 1999-2000, out of a teaching workforce of about 3.45 million, there were about 535,000…

  7. Recent developments in processing HTS silver-clad Bi-2223 tapes, coils and test magnets

    SciTech Connect

    Haldar, P.; Hoehn, J.G. Jr.; Motowidlo, L.R.; Balachandran, U.; Iwasa, Y.; Yunus, M.

    1993-10-01

    Considerable progress has been made in fabricating Bi-2223 high temperature superconductor (HTS) wires and tapes with high critical current densities that are attractive for electric power and high-field magnet applications. Powder-in-tube processed silver-clad Bi-2223 short tape samples, small coils and test magnets have been fabricated and measured at liquid nitrogen (77K), pumped liquid nitrogen (64 K), liquid neon (27K) and liquid helium (4.2K) temperatures. Optimization of thermo-mechanical process parameters have yielded J{sub c}`s in the superconducting core > 4.0 {times} 10{sup 4} A/cm{sup 2} at 77K zero field and > 2.0 {times} 10{sup 5} A/cm{sup 2} at 4.2K, zero field. Long lengths (up to 70 m) of mono-core conductors were fabricated and tested to carry significant amounts of current (23 A, {approximately}15,000 A/cm{sup 2}) at liquid nitrogen temperature. Recent test magnets assembled from pancake wound coils were measured to generate magnetic fields as high as 2.6, 1.8 and 0.36 Tesla at 4.2K, 27K and 77K respectively. These results show promise towards practical utilization of HTS materials.

  8. Development of Wind-and-React Bi-2212 Accelerator MagnetTechnology

    SciTech Connect

    Godeke, A.; Cheng, D.; Dietderich, D.R.; English, C.D.; Felice,H.; Hannaford, C.R.; Prestemon, S.O.; Sabbi, G.; Scanlan, R.M.; Hikichi,Y.; Nishioka, J.; Hasegawa, T.

    2007-08-28

    We report on the progress in our R&D program, targetedto develop the technology for the application of Bi2Sr2CaCu2Ox (Bi-2212)in accelerator magnets. The program uses subscale coils, wound frominsulated cables, to study suitable materials, heat treatmenthomogeneity, stability, and effects ofmagnetic field and thermal andelectro-magnetic loads. We have addressed material and reaction relatedissues and report onthe fabrication, heat treatment, and analysis ofsubscale Bi-2212 coils. Such coils can carry a current on the order of5000 A and generate, in various support structures, magnetic fields from2.6 to 9.9 T. Successful coils are therefore targeted towards a hybridNb3Sn-HTS magnet which will demonstrate the feasibility of Bi-2212 foraccelerator magnets, and open a new magnetic field realm, beyond what isachievable with Nb3Sn.

  9. Collective motion from local attraction.

    PubMed

    Strömbom, Daniel

    2011-08-21

    Many animal groups, for example schools of fish or flocks of birds, exhibit complex dynamic patterns while moving cohesively in the same direction. These flocking patterns have been studied using self-propelled particle models, most of which assume that collective motion arises from individuals aligning with their neighbours. Here, we propose a self-propelled particle model in which the only social force between individuals is attraction. We show that this model generates three different phases: swarms, undirected mills and moving aligned groups. By studying our model in the zero noise limit, we show how these phases depend on the relative strength of attraction and individual inertia. Moreover, by restricting the field of vision of the individuals and increasing the degree of noise in the system, we find that the groups generate both directed mills and three dynamically moving, 'rotating chain' structures. A rich diversity of patterns is generated by social attraction alone, which may provide insight into the dynamics of natural flocks. PMID:21620861

  10. Pyrazines Attract Catocheilus Thynnine Wasps.

    PubMed

    Bohman, Bjorn; Peakall, Rod

    2014-01-01

    Five previously identified semiochemicals from the sexually deceptive Western Australian hammer orchid Drakaea livida, all showing electrophysiological activity in gas chromatography-electroantennogram detection (EAD) studies, were tested in field bioassays as attractants for a Catocheilus thynnine wasp. Two of these compounds, (3,5,6-trimethylpyrazin-2-yl)methyl 3-methylbutanoate and 2-(3-methylbutyl)-3,5,6-trimethylpyrazine, were attractive to male wasps. Additionally, the semiochemical 3-(3-methylbutyl)-2,5-dimethylpyrazine, a close analogue to 2-(3-methylbutyl)-3,5,6-trimethylpyrazine, identified in five other species of thynnine wasps, was equally active. The three remaining compounds from D. livida, which were EAD-active against Catocheilus, did not attract the insects in field trials. It is interesting that two structurally similar compounds induce similar behaviours in field experiments, yet only one of these compounds is present in the orchid flower. Our findings suggest the possibility that despite the high specificity normally characterising sex pheromone systems, the evolution of sexual deception may not be entirely constrained by the need to precisely match the sex pheromone constituents and blends. Such evolutionary flexibility may be particularly important during the early stages of speciation. PMID:26462695

  11. Pyrazines Attract Catocheilus Thynnine Wasps

    PubMed Central

    Bohman, Bjorn; Peakall, Rod

    2014-01-01

    Five previously identified semiochemicals from the sexually deceptive Western Australian hammer orchid Drakaea livida, all showing electrophysiological activity in gas chromatography–electroantennogram detection (EAD) studies, were tested in field bioassays as attractants for a Catocheilus thynnine wasp. Two of these compounds, (3,5,6-trimethylpyrazin-2-yl)methyl 3-methylbutanoate and 2-(3-methylbutyl)-3,5,6-trimethylpyrazine, were attractive to male wasps. Additionally, the semiochemical 3-(3-methylbutyl)-2,5-dimethylpyrazine, a close analogue to 2-(3-methylbutyl)-3,5,6-trimethylpyrazine, identified in five other species of thynnine wasps, was equally active. The three remaining compounds from D. livida, which were EAD-active against Catocheilus, did not attract the insects in field trials. It is interesting that two structurally similar compounds induce similar behaviours in field experiments, yet only one of these compounds is present in the orchid flower. Our findings suggest the possibility that despite the high specificity normally characterising sex pheromone systems, the evolution of sexual deception may not be entirely constrained by the need to precisely match the sex pheromone constituents and blends. Such evolutionary flexibility may be particularly important during the early stages of speciation. PMID:26462695

  12. Attracted diffusion-limited aggregation.

    PubMed

    Rahbari, S H Ebrahimnazhad; Saberi, A A

    2012-07-01

    In this paper we present results of extensive Monte Carlo simulations of diffusion-limited aggregation (DLA) with a seed placed on an attractive plane as a simple model in connection with the electrical double layers. We compute the fractal dimension of the aggregated patterns as a function of the attraction strength α. For the patterns grown in both two and three dimensions, the fractal dimension shows a significant dependence on the attraction strength for small values of α and approaches that of the ordinary two-dimensional (2D) DLA in the limit of large α. For the nonattracting case with α = 1, our results in three dimensions reproduce the patterns of 3D ordinary DLA, while in two dimensions our model leads to the formation of a compact cluster with dimension 2. For intermediate α, the 3D clusters have a quasi-2D structure with a fractal dimension very close to that of the ordinary 2D DLA. This allows one to control the morphology of a growing cluster by tuning a single external parameter α. PMID:23005417

  13. Attracted diffusion-limited aggregation

    NASA Astrophysics Data System (ADS)

    Rahbari, S. H. Ebrahimnazhad; Saberi, A. A.

    2012-07-01

    In this paper we present results of extensive Monte Carlo simulations of diffusion-limited aggregation (DLA) with a seed placed on an attractive plane as a simple model in connection with the electrical double layers. We compute the fractal dimension of the aggregated patterns as a function of the attraction strength α. For the patterns grown in both two and three dimensions, the fractal dimension shows a significant dependence on the attraction strength for small values of α and approaches that of the ordinary two-dimensional (2D) DLA in the limit of large α. For the nonattracting case with α=1, our results in three dimensions reproduce the patterns of 3D ordinary DLA, while in two dimensions our model leads to the formation of a compact cluster with dimension 2. For intermediate α, the 3D clusters have a quasi-2D structure with a fractal dimension very close to that of the ordinary 2D DLA. This allows one to control the morphology of a growing cluster by tuning a single external parameter α.

  14. Development of the ITER magnetic diagnostic set and specification

    SciTech Connect

    Vayakis, G.; Delhom, D.; Encheva, A.; Giacomin, T.; Jones, L.; Patel, K. M.; Portales, M.; Prieto, D.; Simrock, S.; Snipes, J. A.; Udintsev, V. S.; Watts, C.; Winter, A.; Zabeo, L.; Arshad, S.; Perez-Lasala, M.; Sartori, F.

    2012-10-15

    ITER magnetic diagnostics are now in their detailed design and R and D phase. They have passed their conceptual design reviews and a working diagnostic specification has been prepared aimed at the ITER project requirements. This paper highlights specific design progress, in particular, for the in-vessel coils, steady state sensors, saddle loops and divertor sensors. Key changes in the measurement specifications, and a working concept of software and electronics are also outlined.

  15. Progress with developing a target for magnetized target fusion

    SciTech Connect

    Wysocki, F.J.; Chrien, R.E.; Idzorek, G.; Oona, H.; Whiteson, D.O.; Kirkpatrick, R.C.; Lindemuth, I.R.; Sheehey, P.T.

    1997-09-01

    Magnetized Target Fusion (MTF) is an approach to fusion where a preheated and magnetized plasma is adiabatically compressed to fusion conditions. Successful MTF requires a suitable initial target plasma with an embedded magnetic field of at least 5 T in a closed-field-line topology, a density of roughly 10{sup 18} cm{sup {minus}3}, a temperature of at least 50 eV, and must be free of impurities which would raise radiation losses. Target plasma generation experiments are underway at Los Alamos National Laboratory using the Colt facility; a 0.25 MJ, 2--3 {micro}s rise-time capacitor bank. The goal of these experiments is to demonstrate plasma conditions meeting the minimum requirements for a MTF initial target plasma. In the first experiments, a Z-pinch is produced in a 2 cm radius by 2 cm high conducting wall using a static gas-fill of hydrogen or deuterium gas in the range of 0.5 to 2 torr. Thus far, the diagnostics include an array of 12 B-dot probes, framing camera, gated OMA visible spectrometer, time-resolved monochrometer, filtered silicon photodiodes, neutron yield, and plasma-density interferometer. These diagnostics show that a plasma is produced in the containment region that lasts roughly 10 to 20 {micro}s with a maximum plasma density exceeding 10{sup 18} cm{sup {minus}3}. The experimental design and data are presented.

  16. Offset coil designs for superconducting magnets, a logical development

    SciTech Connect

    Collins, T.

    1986-03-01

    Dipoles and quadrupoles for any new, large proton ring must be stronger, smaller and have better field shape (systematic error) than those used in the Doubler. The present two-shell designs are rigid in that the coils are too thin but cannot be relatively fatter without destroying the field quality. An examination of the coil shapes for dipoles and quadrupoles which produce perfect fields from a uniform current density shows clearly that our persistent use of a circular form for the inner surface of the coils is a poor approximation. When this is corrected by ''offsets'' there is a striking improvement both in the strength of fields and in the field quality. The same analysis makes clear that the efficient use of superconductor and the overall magnet size is determined by the perfect coil shapes. Any reasonable magnet will not differ significantly from the ideal for these parameters. This will be particularly helpful in setting design goals for very large quadrupoles. The offset two-shell dipole design preserves the mechanical features of the highly successful, resilient doubler magnets while greatly extending the performance.

  17. Radiation Storm vs. The Magnetic Shield: Superheroes of Magnetism & Space Weather Education - A Model for Teacher Professional Development Workshops

    NASA Astrophysics Data System (ADS)

    Russell, R. M.; Johnson, R. M.

    2010-12-01

    Magnetic and electric fields and phenomena play important roles in various situations in astronomy, planetary science, and Earth science. Students often lack an intuitive sense of electromagnetic phenomena, and therefore struggle with the complexities of planetary and stellar magnetic fields. Hands-on magnetism activities can provide students with an intuitive grasp of the basics of magnetism, preparing them for more challenging conceptual studies of magnetic phenomena. For the past six years, we have been presenting a professional development workshop for teachers covering the topics of magnetism and space weather. The workshop, which has been conducted more than 20 times for a range of audiences, blends together several simple hands-on activities, background information on space weather and geomagnetism, a collection of images, animations, and interactives that illustrate important concepts, and guidance about specific links between these topics and national science education standards. These workshops have been very well-received, and have consistently been rated highly by participants in surveys. We believe the methods used in these workshops can be applied to other topics in science education and to astronomy and Earth science education specifically. In this presentation, we will describe our magnetism and space weather workshop, including some of the hands-on activities. We will describe successful aspects of the workshop and comment on ways we think this approach could be replicated for other topics. We will also display some of the interactives, graphics, and animations shown during the workshops. Resources have been added to the workshop over the years in response to recurring questions from teachers; we will comment on this process and how it might be applied to other topics. The activities and extensive background content used or referenced in the workshop are available for free on the Windows to the Universe web site (www.windows2universe.org). Hands on

  18. Subjective and Objective Facial Attractiveness

    PubMed Central

    Stillman, Mark A.; Frisina, Andrew C.

    2010-01-01

    Background: Studies have not adequately compared subjective/objective ratings of female dermatology patients including patients presenting for cosmetic procedures. Objective: To examine objective versus subjective facial attractiveness ratings, demographic variables, and how men versus women judge female facial attractiveness. Methods: Sixty-five women (mean 42 years) presenting to a dermatology office. Subjects filled out a demographic and attractiveness questionnaire and were photographed. Four judges (2 male and 2 female) rated the photographs on a predefined 1 to 7 scale. Results: Mean subjective rating (subjects rating themselves) was 4.85 versus 3.61 for objective rating (judges rating subjects) (p<0.001). The mean age of subjects self-rating (subjective rating) who rated themselves in the 5 to 7 range was 39 years; the mean age of subjects self-rating (subjective rating) who rated themselves in the 3 to 4 range was 45 years (p=0.053). The mean age of subjects objectively rated by judges in the 5 to 7 range was 33 years; the mean age of subjects objectively rated by judges in the 3 to 4 range was 43 years (p<0.001); and the mean age of subjects objectively rated by judges in the 1 to 2 range was 50 years (p<0.001). The mean subjective rating (subjects rating themselves) for married women was 4.55 versus 5.27 for unmarried women (p=0.007); the mean objective rating (judges rating subjects) was 3.22 versus 4.15 (p<0.001). The mean objective rating by male judges was 3.09 versus 4.12 for female judges (p<0.001) Conclusion: Female patients presenting to a dermatology office rated themselves more attractive than did judges who viewed photographs of the subjects. Age and marital status were significant factors, and male judges rated attractiveness lower than female judges. Limitations of the study, implications, and suggestions for future research directions are discussed. PMID:21203353

  19. Development of the use of in-situ magnets for detection of bed load movement through magnetic induction.

    NASA Astrophysics Data System (ADS)

    Argast, T.

    2009-05-01

    Over the last 100 years, a large number of samplers and bed load measuring devices have been developed in order to estimate sediment transport in rivers. In spite of this work, the geomorphic and engineering communities do not have a reliable method to estimate sediment transport. To better model and understand river dynamics there is an urgent need for a method that can yield detailed estimates of sediment transport in rivers. Available techniques suffer from insufficient temporal and spatial resolution to capture the variability inherent in bed load movement. Data collection from large events can also be dangerous and suffers from problems such as over-filling of pit traps. The use of in-situ magnetic detection devices shows promise as a method that may be able to overcome many of these limitations. These systems have seen limited development by several researchers, the most advanced deployment by Tunnicliffe in 2000 at O'Ne-ell Creek. The sensors work by inducing a magnetic dipole in naturally magnetic stones via magnets installed in the bed of the channel. These stones then pass over a coil of wire, inducing a small voltage, which is recorded. An analysis of the most recent system showed that the sensor had several limitations: the torrid shaped magnet caused double peaks and variable magnetic strength near the face of the sensor and the spacing between the sensors allowed particles to pass over with out detection. To address these issues the new system features a continuous bar magnet, polarized through the thickness, to provide a continuous, uniform field. The previous sensor also produced a narrow range of response for a large range in particle size. This has been improved by using a stronger magnet and coils with a higher induction. Improvements in data storage and computing power since the installation at O'Ne-ell Creek will allow for a higher density of sensor across the channel and higher sampling frequencies. Laboratory experiments have shown that the

  20. Development of Thermoelectric and Permanent Magnet Nanoparticles for Clean Energy Applications

    NASA Astrophysics Data System (ADS)

    Nguyen, Phi-Khanh

    The global trend towards energy efficiency and environmental sustainability has generated a strong demand for clean energy technologies. Among the many energy solutions, the work in this dissertation contributes to two strategic goals: the reduction of fuel consumption in the transportation sector, and the increase of domestic wind power capacity. The key barriers to achieving these goals are materials challenges. Automobiles can be made more efficient by thermoelectric conversion of waste heat from the engine into electricity that can be used to power electrical components in the vehicle. Vehicles can forego petroleum fuel altogether by using electric or hybrid motors. Unfortunately, the conversion efficiency of current thermoelectric technology is too low to be considered economically feasible, and the permanent magnets used in electric vehicle motors and wind turbine generators require critical rare-earth elements that are economically unstable (often referred to as the "rare-earth crisis"). In order to combat these challenges, a "spark erosion" technique was utilized for producing nanoparticles that improve thermoelectric efficiency and contribute to the development of electromotors that do not require rare-earths. In Chapter 2 of this dissertation, I describe the utilization of spark erosion for producing high-quality thermoelectric nanoparticles at a remarkably high rate and with enhanced thermoelectric properties. The technique was employed to synthesize p-type bismuth-antimony telluride (BST) and n-type skutterudite nanoparticles, using a relatively small laboratory apparatus, with low energy consumption. The compacted BST nanocomposite samples made from these nanoparticles exhibit a well-defined, 20--50 nm size nanograin microstructure, and show an enhanced Figure of merit, ZT, of 1.36 at 360 K due to a reduction in lattice thermal conductivity. The skutterudite nanocomposites also show reduced thermal conductivity but still require enhancement in the

  1. Incidental regulation of attraction: the neural basis of the derogation of attractive alternatives in romantic relationships.

    PubMed

    Meyer, Meghan L; Berkman, Elliot T; Karremans, Johan C; Lieberman, Matthew D

    2011-04-01

    Although a great deal of research addresses the neural basis of deliberate and intentional emotion-regulation strategies, less attention has been paid to the neural mechanisms involved in implicit forms of emotion regulation. Behavioural research suggests that romantically involved participants implicitly derogate the attractiveness of alternative partners, and the present study sought to examine the neural basis of this effect. Romantically committed participants in the present study were scanned with functional magnetic resonance imaging (fMRI) while indicating whether they would consider each of a series of attractive (or unattractive) opposite-sex others as a hypothetical dating partner both while under cognitive load and no cognitive load. Successful derogation of attractive others during the no cognitive load compared to the cognitive load trials corresponded with increased activation in the ventrolateral prefrontal cortex (VLPFC) and posterior dorsomedial prefrontal cortex (pDMPFC), and decreased activation in the ventral striatum, a pattern similar to those reported in deliberate emotion-regulation studies. Activation in the VLPFC and pDMPFC was not significant in the cognitive load condition, indicating that while the derogation effect may be implicit, it nonetheless requires cognitive resources. Additionally, activation in the right VLPFC correlated with participants' level of relationship investment. These findings suggest that the RVLPFC may play a particularly important role in implicitly regulating the emotions that threaten the stability of a romantic relationship. PMID:21432689

  2. Incidental regulation of attraction: The neural basis of the derogation of attractive alternatives in romantic relationships

    PubMed Central

    Meyer, Meghan L.; Berkman, Elliot T.; Karremans, Johan C.; Lieberman, Matthew D.

    2011-01-01

    Although a great deal of research addresses the neural basis of deliberate and intentional emotion-regulation strategies, less attention has been paid to the neural mechanisms involved in implicit forms of emotion regulation. Behavioural research suggests that romantically involved participants implicitly derogate the attractiveness of alternative partners, and the present study sought to examine the neural basis of this effect. Romantically committed participants in the present study were scanned with functional magnetic resonance imaging (fMRI) while indicating whether they would consider each of a series of attractive (or unattractive) opposite-sex others as a hypothetical dating partner both while under cognitive load and no cognitive load. Successful derogation of attractive others during the no cognitive load compared to the cognitive load trials corresponded with increased activation in the ventrolateral prefrontal cortex (VLPFC) and posterior dorsomedial prefrontal cortex (pDMPFC), and decreased activation in the ventral striatum, a pattern similar to those reported in deliberate emotion-regulation studies. Activation in the VLPFC and pDMPFC was not significant in the cognitive load condition, indicating that while the derogation effect may be implicit, it nonetheless requires cognitive resources. Additionally, activation in the right VLPFC correlated with participants’ level of relationship investment. These findings suggest that the RVLPFC may play a particularly important role in implicitly regulating the emotions that threaten the stability of a romantic relationship. PMID:21432689

  3. Magnetic resonance microscopy of prostate tissue: How basic science can inform clinical imaging development

    SciTech Connect

    Bourne, Roger

    2013-03-15

    This commentary outlines how magnetic resonance imaging (MRI) microscopy studies of prostate tissue samples and whole organs have shed light on a number of clinical imaging mysteries and may enable more effective development of new clinical imaging methods.

  4. Anatomical Brain Magnetic Resonance Imaging of Typically Developing Children and Adolescents

    ERIC Educational Resources Information Center

    Giedd, Jay N.; Lalonde, Francois M.; Celano, Mark J.; White, Samantha L.; Wallace, Gregory L.; Lee, Nancy R.; Lenroot, Rhoshel K.

    2009-01-01

    Methodological issues relevant to magnetic resonance imaging studies of brain anatomy are discussed along with the findings on the neuroanatomic changes during childhood and adolescence. The development of the brain is also discussed.

  5. Development of optical modulators for measurements of solar magnetic fields

    NASA Astrophysics Data System (ADS)

    West, E. A.; Smith, J. E.

    1987-10-01

    The measurement of polarized light allows solar astronomers to infer the magnetic field on the Sun. The accuracy of these measurements is dependent on the stable retardation characteristics of the polarization modulators used to minimize the atmospheric effects seen in ground-based observations. This report describes the work by the Space Science Laboratory at Marshall Space Flight Center to improve two types of polarization modulators. As a result, the timing characteristics for both electrooptic crystals (KD*Ps) and liquid crystal devices (LCDs) have been studied and will be used to enhance the capabilities of the MSFC Vector Magnetograph.

  6. Development of optical modulators for measurements of solar magnetic fields

    NASA Technical Reports Server (NTRS)

    West, E. A.; Smith, J. E.

    1987-01-01

    The measurement of polarized light allows solar astronomers to infer the magnetic field on the Sun. The accuracy of these measurements is dependent on the stable retardation characteristics of the polarization modulators used to minimize the atmospheric effects seen in ground-based observations. This report describes the work by the Space Science Laboratory at Marshall Space Flight Center to improve two types of polarization modulators. As a result, the timing characteristics for both electrooptic crystals (KD*Ps) and liquid crystal devices (LCDs) have been studied and will be used to enhance the capabilities of the MSFC Vector Magnetograph.

  7. 18T resistive magnet development. Conceptual design second annual report

    SciTech Connect

    Agarwal, K.L.; Burgeson, J.E.; Gurol, H.; Mancuso, A.; Michels, P.H.

    1985-10-01

    This report documents the work performed on a normal conducting magnet during fiscal year 1985. Emphasis, during the study, was on refinement of the structural design and optimization of the coil current density distribution for either maximum field generation or minimum power consumption. The results have shown that one can generate a 4.4 tesla field using 6.14 megawatts or 3.1 tesla at 1.43 megawatts. The structural design has been modified to stiffen the outer turn of the conductor. The modification was confirmed to be structurally adequate by both analysis and test. 37 figs., 21 tabs.

  8. Developing a Solar Magnetic Catalog Spanning Four Cycles

    NASA Astrophysics Data System (ADS)

    Werginz, Zachary; Munoz-Jaramillo, Andres; DeLuca, Michael D.; Vargas Acosta, Juan Pablo; Vargas Dominguez, Santiago; Zhang, Jie; Longcope, Dana; Martens, Petrus C.

    2016-05-01

    Bipolar magnetic regions (BMRs) are the cornerstone of solar cycle propagation, the building blocks that give structure to the solar atmosphere, and the origin of the majority of space weather events. However, in spite of their importance, there is no homogeneous BMR catalog spanning the era of systematic solar magnetic field measurements. Here we present the results of an ongoing project to address this deficiency applying the Bipolar Active Region Detection (BARD) code to magnetograms from the 512 Channel of the Kitt Peak Vaccum Telescope, SOHO/MDI, and SDO/HMI.The BARD code automatically identifies BMRs and tracks them as they are rotated by differential rotation. The output of the automatic detection is supervised by a human observer to correct possible mistakes made by the automatic algorithm (like incorrect pairings and tracking mislabels). Extra passes are made to integrate fragmented regions as well as to balance the flux between BMR polarities. At the moment, our BMR database includes 6,885 unique objects (detected and tracked) belonging to four separate solar cycles (21-24).

  9. Acarine attractants: Chemoreception, bioassay, chemistry and control.

    PubMed

    Carr, Ann L; Roe, Michael

    2016-07-01

    The Acari are of significant economic importance in crop production and human and animal health. Acaricides are essential for the control of these pests, but at the same time, the number of available pesticides is limited, especially for applications in animal production. The Acari consist of two major groups, the mites that demonstrate a wide variety of life strategies, i.e., herbivory, predation and ectoparasitism, and ticks which have evolved obligatory hematophagy. The major sites of chemoreception in the acarines are the chelicerae, palps and tarsi on the forelegs. A unifying name, the "foretarsal sensory organ" (FSO), is proposed for the first time in this review for the sensory site on the forelegs of all acarines. The FSO has multiple sensory functions including olfaction, gustation, and heat detection. Preliminary transcriptomic data in ticks suggest that chemoreception in the FSO is achieved by a different mechanism from insects. There are a variety of laboratory and field bioassay methods that have been developed for the identification and characterization of attractants but minimal techniques for electrophysiology studies. Over the past three to four decades, significant progress has been made in the chemistry and analysis of function for acarine attractants in mites and ticks. In mites, attractants include aggregation, immature female, female sex and alarm pheromones; in ticks, the attraction-aggregation-attachment, assembly and sex pheromones; in mites and ticks host kairomones and plant allomones; and in mites, fungal allomones. There are still large gaps in our knowledge of chemical communication in the acarines compared to insects, especially relative to acarine pheromones, and more so for mites than ticks. However, the use of lure-and-kill and lure-enhanced biocontrol strategies has been investigated for tick and mite control, respectively, with significant environmental advantages which warrant further study. PMID:27265828

  10. Development of magnetic fabric in sedimentary rocks: insights from early compactional structures

    NASA Astrophysics Data System (ADS)

    García-Lasanta, Cristina; Oliva-Urcia, Belén; Román-Berdiel, Teresa; Casas, Antonio M.; Pérez-Lorente, Félix

    2013-07-01

    The timing of development of the magnetic fabric is a major issue in the application of anisotropy of magnetic susceptibility (AMS) as a strain marker. Analysis of AMS in unconcealed synsedimentary structures can be a sound approximation to this task. In this work, three types of early compactional structures (ECS) were studied by means of AMS, since they can help to understand the timing of development of the magnetic fabric. All three types of ECS are found in fine-grained detrital rocks (to avoid other influences such as palaeocurrents), claystones and marls of the Enciso Group within the Cameros Basin (NE Spain): dinosaur footprints, load structures due to differential compaction and dish-and-flame structures associated with fluid migration related to seismites. In addition, to determine possible influences of lithology on the magnetic fabric, different rock types (siltstones and limestones) were also sampled. In general, the influence of ECS results in scattering of the three magnetic axes, higher at the margins of the structure than at its centre. This fact suggests that ECS occurs during the development of the magnetic fabric, disturbing the incipient magnetic fabric stages, and strongly conditions its later evolution during diagenesis. The later homogeneous compaction process due to sedimentary load and physicochemical processes reorient the susceptibility carriers to some extent (i.e. the magnetic fabric is still under development), but not totally, since AMS still records the previous scattering due to ECS imprint. For the Enciso Group deposits, the magnetic fabric begins to develop at the earliest stages after deposition and it stops when diagenetic processes have finished.

  11. Development of integrated AC-DC magnetometer using high-Tc SQUID for magnetic properties evaluation of magnetic nanoparticles in solution

    NASA Astrophysics Data System (ADS)

    Mawardi Saari, Mohd; Takagi, Ryuki; Kusaka, Toki; Ishihara, Yuichi; Tsukamoto, Yuya; Sakai, Kenji; Kiwa, Toshihiko; Tsukada, Keiji

    2014-05-01

    We developed an integrated AC-DC magnetometer using a high critical temperature superconducting quantum interference device (high-Tc SQUID) to evaluate the static and dynamic magnetic properties of magnetic nanoparticles (MNPs) in solution. The flux-transformer method consisted of first-order planar and axial differential coils that were constructed for static and dynamic magnetization measurements, respectively. Vibrating-sample and harmonic detection techniques were used to reduce interference from excitation magnetic fields in the static and dynamic magnetization measurements, respectively. Static and dynamic magnetization measurements were performed on commercially available iron oxide nanoparticles in diluted solutions. The magnetic responses increased with the increase in concentration of the solutions in both measurement results. The magnetization curves showed that the diamagnetic signal due to the carrier liquid of the iron oxide nanoparticles existed in a dilute solution. Biasing with a proper DC magnetic field in the dynamic magnetization measurement resulted in improved signals of the second and third harmonics. Therefore, highly sensitive magnetic characterizations of MNPs utilizing the static and dynamic magnetization measurement are possible via the developed system.

  12. Epoxy resin developments for large superconducting magnets impregnation

    NASA Astrophysics Data System (ADS)

    Rey, J. M.; Gallet, B.; Kircher, F.; Lottin, J. C.

    The future detectors ATLAS and CMS of the Large Hadron Collider at CERN will use two huge superconducting magnets. Both are now under design, and their electrical insulation could be realized using epoxy resin and a wet impregnation technique. Because of their large dimensions, and the indirect cooling of the superconductor, the strengths of the resin and of the resin/conductor interface are of major importance. A new generation of epoxy resins for vacuum/pressure impregnation methods has been tested, and compared with some classical and well-known epoxy resins used in impregnation techniques. In order to understand the mechanical behaviour at 4 K, the complete evolution from liquid state to low temperature service condition is considered. The paper will present some results on the mechanical properties, the density and the chemical shrinkage occurring during the polymerization and the thermal contraction between room temperature and 4 K for these different types of epoxy resins.

  13. Development of high-stability magnet power supply

    NASA Astrophysics Data System (ADS)

    Choi, W. S.; Kim, M. J.; Jeong, I. W.; Kim, D. E.; Park, H. C.; Park, K. H.

    2016-06-01

    A very stable (≤10 ppm) magnet power supply (MPS) is required in an accelerator to achieve acceptable beam dynamics. Many factors affect the stability of an MPS, so design of the MPS requires much attention to noise-reduction schemes and to good processing of the signals from the feedback stage. This paper describes some design considerations for an MPS installed and operated in the Pohang Accelerator Laboratory: (1) control method, (2) oversampling technology, (3) ground isolation between hardware modules and (4) low-pass filter design to reduce the switching noise and rectifier ripple components, and shows the stability of three designed devices. The MPS design considerations were verified and validated in simulations and experiments. This paper also shows the relationship between stability and measurement aperture time of digital voltage meter 3458 A to measure stability of a current.

  14. Children's Facial Trustworthiness Judgments: Agreement and Relationship with Facial Attractiveness

    PubMed Central

    Ma, Fengling; Xu, Fen; Luo, Xianming

    2016-01-01

    This study examined developmental changes in children's abilities to make trustworthiness judgments based on faces and the relationship between a child's perception of trustworthiness and facial attractiveness. One hundred and one 8-, 10-, and 12-year-olds, along with 37 undergraduates, were asked to judge the trustworthiness of 200 faces. Next, they issued facial attractiveness judgments. The results indicated that children made consistent trustworthiness and attractiveness judgments based on facial appearance, but with-adult and within-age agreement levels of facial judgments increased with age. Additionally, the agreement levels of judgments made by girls were higher than those by boys. Furthermore, the relationship between trustworthiness and attractiveness judgments increased with age, and the relationship between two judgments made by girls was closer than those by boys. These findings suggest that face-based trait judgment ability develops throughout childhood and that, like adults, children may use facial attractiveness as a heuristic cue that signals a stranger's trustworthiness. PMID:27148111

  15. Children's Facial Trustworthiness Judgments: Agreement and Relationship with Facial Attractiveness.

    PubMed

    Ma, Fengling; Xu, Fen; Luo, Xianming

    2016-01-01

    This study examined developmental changes in children's abilities to make trustworthiness judgments based on faces and the relationship between a child's perception of trustworthiness and facial attractiveness. One hundred and one 8-, 10-, and 12-year-olds, along with 37 undergraduates, were asked to judge the trustworthiness of 200 faces. Next, they issued facial attractiveness judgments. The results indicated that children made consistent trustworthiness and attractiveness judgments based on facial appearance, but with-adult and within-age agreement levels of facial judgments increased with age. Additionally, the agreement levels of judgments made by girls were higher than those by boys. Furthermore, the relationship between trustworthiness and attractiveness judgments increased with age, and the relationship between two judgments made by girls was closer than those by boys. These findings suggest that face-based trait judgment ability develops throughout childhood and that, like adults, children may use facial attractiveness as a heuristic cue that signals a stranger's trustworthiness. PMID:27148111

  16. Exploring Ultrahigh Magnetic Field Processing of Materials for Developing Customized Microstructures and Enhanced Performance

    SciTech Connect

    Ludtka, GERALD M.

    2005-03-31

    Thermodynamic calculations based on Gibbs free energy in the magnetization-magnetic intensity-temperature (M-H-T) magnetic equation of state space demonstrate that significantly different phase equilibria may result for those material systems where the product and parent phases exhibit different magnetization responses. These calculations show that the Gibbs free energy is changed by a factor equal to -MdH, where M and H are the magnetization and applied field strength, respectively. Magnetic field processing is directly applicable to a multitude of alloys and compounds for dramatically influencing phase stability and phase transformations. This ability to selectively control microstructural stability and alter transformation kinetics through appropriate selection of the magnetic field strength promises to provide a very robust mechanism for developing and tailoring enhanced microstructures (and even nanostructures through accelerated kinetics) with superior properties for a broad spectrum of material applications. For this Industrial Materials for the Future (IMF) Advanced Materials for the Future project, ferrous alloys were studied initially since this alloy family exhibits ferromagnetism over part of its temperature range of stability and therefore would demonstrate the maximum impact of this novel processing mechanism. Additionally, with these ferrous alloys, the high-temperature parent phase, austenite, exhibits a significantly different magnetization response from the potential product phases, ferrite plus carbide or martensite; and therefore, the solid-state transformation behavior of these alloys will be dramatically influenced by the presence of ultrahigh magnetic fields. Finally, a thermodynamic calculation capability (within ThermoCalc for example) was developed during this project to enable parametric studies to be performed to predict the magnitude of the influence of magnetic processing variables on the phase stability (phase diagrams) in

  17. Effects of Switching Behavior for the Attraction on Pedestrian Dynamics

    PubMed Central

    Kwak, Jaeyoung; Jo, Hang-Hyun; Luttinen, Tapio; Kosonen, Iisakki

    2015-01-01

    Walking is a fundamental activity of our daily life not only for moving to other places but also for interacting with surrounding environment. While walking on the streets, pedestrians can be aware of attractions like shopping windows. They can be influenced by the attractions and some of them might shift their attention towards the attractions, namely switching behavior. As a first step to incorporate the switching behavior, this study investigates collective effects of switching behavior for an attraction by developing a behavioral model. Numerical simulations exhibit different patterns of pedestrian behavior depending on the strength of the social influence and the average length of stay. When the social influence is strong along with a long length of stay, a saturated phase can be defined at which all the pedestrians have visited the attraction. If the social influence is not strong enough, an unsaturated phase appears where one can observe that some pedestrians head for the attraction while others walk in their desired direction. These collective patterns of pedestrian behavior are summarized in a phase diagram by comparing the number of pedestrians who visited the attraction to the number of passersby near the attraction. Measuring the marginal benefits with respect to the strength of the social influence and the average length of stay enables us to identify under what conditions enhancing these variables would be more effective. The findings from this study can be understood in the context of the pedestrian facility management, for instance, for retail stores. PMID:26218430

  18. Liquid Crystal Phase Behaviour of Attractive Disc-Like Particles

    PubMed Central

    Wu, Liang; Jackson, George; Müller, Erich A.

    2013-01-01

    We employ a generalized van der Waals-Onsager perturbation theory to construct a free energy functional capable of describing the thermodynamic properties and orientational order of the isotropic and nematic phases of attractive disc particles. The model mesogen is a hard (purely repulsive) cylindrical disc particle decorated with an anisotropic square-well attractive potential placed at the centre of mass. Even for isotropic attractive interactions, the resulting overall inter-particle potential is anisotropic, due to the orientation-dependent excluded volume of the underlying hard core. An algebraic equation of state for attractive disc particles is developed by adopting the Onsager trial function to characterize the orientational order in the nematic phase. The theory is then used to represent the fluid-phase behaviour (vapour-liquid, isotropic-nematic, and nematic-nematic) of the oblate attractive particles for varying values of the molecular aspect ratio and parameters of the attractive potential. When compared to the phase diagram of their athermal analogues, it is seen that the addition of an attractive interaction facilitates the formation of orientationally-ordered phases. Most interestingly, for certain aspect ratios, a coexistence between two anisotropic nematic phases is exhibited by the attractive disc-like fluids. PMID:23965962

  19. Recent progress towards developing a high field, high-T(sub c) superconducting magnet for magnetic suspension and balance systems

    NASA Technical Reports Server (NTRS)

    Derochemont, L. Pierre; Oakes, Carlton E.; Squillante, Michael R.; Duan, Hong-Min; Hermann, Allen M.; Andrews, Robert J.; Poeppel, Roger B.; Maroni, Victor A.; Carlberg, Ingrid A.; Kelliher, Warren C.

    1992-01-01

    This paper reviews superconducting magnets and high T(sub c) superconducting oxide ceramic materials technology to identify areas of fundamental impasse to the fabrication of components and devices that tap what are believed to be the true potential of these new materials. High T(sub c) ceramics pose problems in fundamentally different areas which need to be solved unlike low T(sub c) materials. The authors map out an experimental plan designed to research process technologies which, if suitably implemented, should allow these deficiencies to be solved. Finally, assessments are made of where and on what regimes magnetic system designers should focus their attention to advance the practical development of systems based on these new materials.

  20. Basins of attraction for chimera states

    NASA Astrophysics Data System (ADS)

    Martens, Erik A.; Panaggio, Mark J.; Abrams, Daniel M.

    2016-02-01

    Chimera states—curious symmetry-broken states in systems of identical coupled oscillators—typically occur only for certain initial conditions. Here we analyze their basins of attraction in a simple system comprised of two populations. Using perturbative analysis and numerical simulation we evaluate asymptotic states and associated destination maps, and demonstrate that basins form a complex twisting structure in phase space. Understanding the basins’ precise nature may help in the development of control methods to switch between chimera patterns, with possible technological and neural system applications.

  1. Progress in the Development of the Wuhan High Magnetic Field Center

    NASA Astrophysics Data System (ADS)

    Li, L.; Peng, T.; Ding, H. F.; Han, X. T.; Xia, Z. C.; Ding, T. H.; Wang, J. F.; Xie, J. F.; Wang, S. L.; Huang, Y.; Duan, X. Z.; Yao, K. L.; Herlach, F.; Vanacken, J.; Pan, Y.

    2010-04-01

    Since April 2008 the Wuhan High Magnetic Field Center (WHMFC) has been under development at the Huazhong University of Science and Technology (HUST) at Wuhan, China. It is funded by the Chinese National Development and Reformation Committee. Magnets with bore sizes from 12 to 34 mm and peak fields in the range of 50 to 80 T have been designed. The power supplies for these magnets are a capacitor bank with 12 modules of 1 MJ, 25 kV each and a 100 MVA/100 MJ flywheel pulse generator. The objective of the facility is to accommodate external users for extensive experiments in pulsed high magnetic fields. Up to seven measurement stations will be available at temperatures in the range from 50 mK to 400 K. The first prototype 1 MJ, 25 kV capacitor bank with thyristors, crowbar diodes and a mechanical switch has been developed and successfully tested. For the protection of the thyristor switch, a toroidal inductor is developed to limit the current at 40 kA. Five magnets have been wound with CuNb and copper wires and internal reinforcement by Zylon fiber; external reinforcement is a stainless steel shell encased by carbon fiber composite. Two Helium flow cryostats have been successfully tested and reached temperatures down to 4.2 K. Measurement stations for magneto-transport and magnetization are in operation. The design, construction and testing of the prototype system are presented.

  2. Development and Testing of a Magnetically Actuated Capsule Endoscopy for Obesity Treatment.

    PubMed

    Do, Thanh Nho; Seah, Tian En Timothy; Ho, Khek Yu; Yu, Ho Khek; Phee, Soo Jay

    2016-01-01

    Intra-gastric balloons (IGB) have become an efficient and less invasive method for obesity treatment. The use of traditional IGBs require complex insertion tools and flexible endoscopes to place and remove the balloon inside the patient's stomach, which may cause discomfort and complications to the patient. This paper introduces a new ingestible weight-loss capsule with a magnetically remote-controlled inflatable and deflatable balloon. To inflate the balloon, biocompatible effervescent chemicals are used. As the source of the actuation is provided via external magnetic fields, the magnetic capsule size can be significantly reduced compared to current weight-loss capsules in the literature. In addition, there are no limitations on the power supply. To lose weight, the obese subject needs only to swallow the magnetic capsule with a glass of water. Once the magnetic capsule has reached the patient's stomach, the balloon will be wirelessly inflated to occupy gastric space and give the feeling of satiety. The balloon can be wirelessly deflated at any time to allow the magnetic capsule to travel down the intestine and exit the body via normal peristalsis. The optimal ratio between the acid and base to provide the desired gas volume is experimentally evaluated and presented. A prototype capsule (9.6mm x 27mm) is developed and experimentally validated in ex-vivo experiments. The unique ease of delivery and expulsion of the proposed magnetic capsule is slated to make this development a good treatment option for people seeking to lose excess weight. PMID:26815309

  3. Molecular attraction of condensed bodies

    NASA Astrophysics Data System (ADS)

    Derjaguin, B. V.; Abrikosova, I. I.; Lifshitz, E. M.

    2015-09-01

    From the Editorial Board. As a contribution to commemorating the 100th anniversary of the birth of Evgenii Mikhailovich Lifshitz, it was found appropriate by the Editorial Board of Uspekhi Fizicheskikh Nauk (UFN) [Physics-Uspekhi] journal that the materials of the jubilee-associated Scientific Session of the Physical Sciences Division of the Russian Academy of Sciences published in this issue (pp. 877-905) be augmented by the review paper "Molecular attraction of condensed bodies" reproduced from a 1958 UFN issue. Included in this review, in addition to an account by Evgenii Mikhailovich Lifshitz of his theory of molecular attractive forces between condensed bodies (first published in Zhurnal Eksperimental'noi i Teoreticheskoi Fiziki (ZhETF) in 1955 and in its English translation Journal of Experimental and Theoretical Physics (JETP) in 1956), is a summary of a series of experimental studies beginning in 1949 by Irina Igorevna Abrikosova at the Institute of Physical Chemistry of the Academy of Sciences of the USSR in a laboratory led by Boris Vladimirovich Derjaguin (1902-1994), a Corresponding Member of the USSR Academy of Sciences. In 1958, however, UFN was not yet available in English translation, so the material of the review is insufficiently accessible to the present-day English-speaking reader. This is the reason why the UFN Editorial Board decided to contribute to celebrating the 100th anniversary of E M Lifshitz's birthday by reproducing on the journal's pages a 1958 review paper which contains both E M Lifshitz's theory itself and the experimental data that underpinned it (for an account of how Evgenii Mikhailovich Lifshitz was enlisted to explain the experimental results of I I Abrikosova and B V Derjaguin, see the letter to the editors N P Danilova on page 925 of this jubilee collection of publications).

  4. Development of a Non-Magnetic Inertial Sensor for Vibration Stabilization in a Linear Collider

    SciTech Connect

    Frisch, Josef; Decker, Valentin; Doyle, Eric; Hendrickson, Linda; Himel, Thomas; Markiewicz, Thomas; Seryi, Andrei; Chang, Allison; Partridge, Richard; /Brown U.

    2006-09-01

    One of the options for controlling vibration of the final focus magnets in a linear collider is to use active feedback based on accelerometers. While commercial geophysics sensors have noise performance that substantially exceeds the requirements for a linear collider, they are physically large, and cannot operate in the strong magnetic field of the detector. Conventional nonmagnetic sensors have excessive noise for this application. We report on the development of a non-magnetic inertial sensor, and on a novel commercial sensor both of which have demonstrated the required noise levels for this application.

  5. Development of a Clinical Functional Magnetic Resonance Imaging Service

    PubMed Central

    Rigolo, Laura; Stern, Emily; Deaver, Pamela; Golby, Alexandra J.; Mukundan, Srinivasan

    2013-01-01

    One of the limitations of anatomical based imaging approaches is its relative inability to identify whether specific brain functions may be compromised by the location of brain lesions or contemplated brain surgeries. For this reason, methods for identifying the regions of eloquent brain that should not be disturbed are absolutely critical to the surgeon. By accurately identifying these regions preoperatively, virtually every pre-surgical decision from the surgical approach, operative goals (biopsy, sub-total vs. gross-total resection), and the potential need for awake craniotomy with intraoperative cortical-mapping is affected. Of the many techniques available to the surgeon, functional magnetic resonance imaging (fMRI) has become the primary modality of choice due to the ability of MRI to serve as a “one-stop shop” for assessing both anatomy and functionality of the brain. Given their prevalence, brain tumors serve as the model pathology for the included discussion; however, a similar case can be made for the use of fMRI in other neurological conditions, most notably epilepsy. The value of fMRI was validated in 2007 when the Centers for Medicare and Medicaid Services (CMS) established three new current procedural terminology (CPT) codes for clinical fMRI based upon its use for pre-therapeutic planning. In this article we will discuss the specific requirements for establishing an fMRI program, including specific software and hardware requirements. In addition, the nature of the fMRI CPT codes will be discussed. PMID:21435578

  6. Superconducting magnet performance for 28 GHz electron cyclotron resonance ion source developed at the Korea Basic Science Institute

    SciTech Connect

    Park, Jin Yong; Choi, Seyong; Lee, Byoung-Seob; Yoon, Jang-Hee; Ok, Jung-Woo; Shin, Chang Seouk; Won, Mi-Sook; Kim, Byoung Chul; Ahn, Jung Keun

    2014-02-15

    A superconducting magnet for use in an electron cyclotron resonance ion source was developed at the Korea Basic Science Institute. The superconducting magnet is comprised of three solenoids and a hexapole magnet. According to the design value, the solenoid magnets can generate a mirror field, resulting in axial magnetic fields of 3.6 T at the injection area and 2.2 T at the extraction region. A radial field strength of 2.1 T can also be achieved by hexapole magnet on the plasma chamber wall. NbTi superconducting wire was used in the winding process following appropriate techniques for magnet structure. The final assembly of the each magnet involved it being vertically inserted into the cryostat to cool down the temperature using liquid helium. The performance of each solenoid and hexapole magnet was separately verified experimentally. The construction of the superconducting coil, the entire magnet assembly for performance testing and experimental results are reported herein.

  7. Development of Rare-Earth Free Mn-Al Permanent Magnet Employing Powder Metallurgy Route

    NASA Astrophysics Data System (ADS)

    Singh, N.; Shyam, R.; Upadhyay, N. K.; Dhar, A.

    2015-02-01

    Most widely used high-performance permanent magnets are currently based on intermetallics of rare-earths in combination with Fe and Co. Rare-earth elements required for these magnets are getting expensive by the day. Consequently, there is a thrust worldwide to develop economical rare-earth free permanent magnets. It is acknowledged that the phase in Mn-Al alloys possesses magnetic properties without the presence of ferromagnetic elements such as Fe, Co, and Ni. In the present study, we report the synthesis of magnetic phase of Mn54Al46 alloy synthesized using mechanical alloying followed by solutionizing and annealing to obtain the desired magnetic phase. It is well known that Al dissolves partially in Mn matrix hence supersaturated solid solution of Mn54Al46 alloy powder was obtained by mechanical alloying using a planetary high-energy ball mill. For this purpose elemental Mn and Al powders were ball-milled in Argon atmosphere at 400 rpm using stainless steel bowl with ball to powder ratio of 15:1. These mechanically alloyed Mn54Al46 powders were then consolidated using spark plasma sintering at 550°C for 20 min. followed by solution treatment at 1050°C for 5 hrs and then water quenched to retain high temperature phase. Subsequently, the Mn54Al46 samples were annealed in the temperature range 450°C-650°C to obtain the magnetic phase. These samples were characterized by XRD and SEM and the magnetic properties were measured using a vibrating sample magnetometer (VSM). It was observed that the magnetization and coercivity of MnAl magnets exhibited strong dependence on annealing temperature and annealing time.

  8. The Development of Magnetic Molecules for the Selective Removal of Contaminants

    SciTech Connect

    Bushart, S.P.; Bradbury, D.; Elder, G.; Duffield, J.; Pascual, I.; Ratcliffe, N.

    2006-07-01

    'Magnetic molecules' are a new type of decontaminant for removing dilute dissolved contaminants from solution. Magnetic molecules have a specific ion exchange function to selectively react with a particular type of ionic contamination in a liquid solution. The magnetic molecules also have a very small magnetic ferritin core (ferritin is an iron-III mammalian storage protein having about 10 nm diameter), which enables the magnetic molecule to be removed from solution by magnetic filtration. The ion exchange function is attached to the magnetic ferritin core by organic reaction sequences. The ion exchange function selectively bonds to a specific type of contaminant ion. For example, ion exchange functions can selectively target radioactive contaminant ions such as cobalt, cesium and plutonium. The procedure for decontamination is that the appropriate magnetic molecule (which targets the contaminant which it is desired to remove) is added to the solution and the solution is then passed through a magnetic filter. The contaminant binds to the magnetic molecule and is then removed by the magnetic filter. The magnetic molecule/contaminant can then be recovered from the magnetic filter by back-washing. Work has been undertaken towards the development of magnetic molecules for use as radioactive decontaminants for radioactive waste management purposes. Previously we have reported on the functionalization of ferritin with the chelating agent DTPA and have shown that this can be used to bind Ca(II) in solution and separate it from Na(I) ions by the process of equilibrium dialysis. Approximately 100 DTPA molecules could be bound to the surface of the ferritin molecule. Synthetic conditions have been optimised, and which will be reported here, ferritin has been functionalized with approximately 1200 DTPA molecules per mole of ferritin and used successfully to achieve a quantitative separation of Co(II) from Cs(I) ions by equilibrium dialysis. This separation has been carried

  9. Engineered Magnetic Core-Shell Structures.

    PubMed

    Alavi Nikje, Mir Mohammad; Vakili, Maryam

    2015-01-01

    In recent years, engineered magnetic core-shell structures are playing an important role in the wide range of various applications. These magnetic core-shell structures have attracted considerable attention because of their unique properties and various applications. Also, the synthesis of engineered magnetic core-shell structures has attracted practical interest because of potential applications in areas such as ferrofluids, medical imaging, drug targeting and delivery, cancer therapy, separations, and catalysis. So far a large number of engineered magnetic core-shell structures have been successfully synthesized. This review article focuses on the recent progress in synthesis and characterization of engineered magnetic core-shell structures. Also, this review gives a brief description of the various application of these structures. It is hoped that this review will play some small part in helping future developments in important field. PMID:26377655

  10. Development of alternating current transmitter of detection system for magnetic material in soil subsurface

    NASA Astrophysics Data System (ADS)

    Indrasari, Widyaningrum; Djamal, Mitra; Srigutomo, Wahyu; Ramli

    2016-03-01

    Generally, detection system for magnetic material in soil subsurface using electromagnetic induction method consists of two parts, they are transmitter and receiver unit. A transmitter must be able to produce a continuous and stable AC current at a certain frequency, meanwhile receiver should be able to catch the secondary magnetic field of magnetic material in soil subsurface. The aim of this study was to develop a new AC current transmitter of detection system for the magnetic material in soil subsurface. This paper will describe the results of the development of AC current transmitter systems, distance characterization of the sensor detection toward horizontal solenoid positions, and characterization of magnetic material in the soil subsurface. It has successfully made the AC current transmitter system, composed of a sinusoidal signal generator, power amplifier, and a source of AC magnetic field. The output of the generator has a frequency varies: 1 kHz, 2 kHz, 5 kHz, and 10 kHz. We found that the AC current transmitter that has been developed able to work properly up to a frequency of 10 kHz.

  11. Interpersonal Congruency, Attitude Similarity, and Interpersonal Attraction

    ERIC Educational Resources Information Center

    Touhey, John C.

    1975-01-01

    As no experimental study has examined the effects of congruency on attraction, the present investigation orthogonally varied attitude similarity and interpersonal congruency in order to compare the two independent variables as determinants of interpersonal attraction. (Author/RK)

  12. Platinum dendritic nanoparticles with magnetic behavior

    NASA Astrophysics Data System (ADS)

    Li, Wenxian; Sun, Ziqi; Tian, Dongliang; Nevirkovets, Ivan P.; Dou, Shi-Xue

    2014-07-01

    Magnetic nanoparticles have attracted increasing attention for biomedical applications in magnetic resonance imaging, high frequency magnetic field hyperthermia therapies, and magnetic-field-gradient-targeted drug delivery. In this study, three-dimensional (3D) platinum nanostructures with large surface area that features magnetic behavior have been demonstrated. The well-developed 3D nanodendrites consist of plentiful interconnected nano-arms ˜4 nm in size. The magnetic behavior of the 3D dendritic Pt nanoparticles is contributed by the localization of surface electrons due to strongly bonded oxygen/Pluronic F127 and the local magnetic moment induced by oxygen vacancies on the neighboring Pt and O atoms. The magnetization of the nanoparticles exhibits a mixed paramagnetic and ferromagnetic state, originating from the core and surface, respectively. The 3D nanodendrite structure is suitable for surface modification and high amounts of drug loading if the transition temperature was enhanced to room temperature properly.

  13. Platinum dendritic nanoparticles with magnetic behavior

    SciTech Connect

    Li, Wenxian; Sun, Ziqi; Nevirkovets, Ivan P.; Dou, Shi-Xue; Tian, Dongliang

    2014-07-21

    Magnetic nanoparticles have attracted increasing attention for biomedical applications in magnetic resonance imaging, high frequency magnetic field hyperthermia therapies, and magnetic-field-gradient-targeted drug delivery. In this study, three-dimensional (3D) platinum nanostructures with large surface area that features magnetic behavior have been demonstrated. The well-developed 3D nanodendrites consist of plentiful interconnected nano-arms ∼4 nm in size. The magnetic behavior of the 3D dendritic Pt nanoparticles is contributed by the localization of surface electrons due to strongly bonded oxygen/Pluronic F127 and the local magnetic moment induced by oxygen vacancies on the neighboring Pt and O atoms. The magnetization of the nanoparticles exhibits a mixed paramagnetic and ferromagnetic state, originating from the core and surface, respectively. The 3D nanodendrite structure is suitable for surface modification and high amounts of drug loading if the transition temperature was enhanced to room temperature properly.

  14. Optical field and attractive force at the subwavelength slit.

    PubMed

    Shapiro, David; Nies, Daniel; Belai, Oleg; Wurm, Matthias; Nesterov, Vladimir

    2016-07-11

    In recent works, a novel light-induced attractive force was predicted between two metal plates. This force arises by the interaction of surface plasmons which are excited at the metal when a transverse magnetic mode propagates through a subwavelength slit between two metal bodies. In this paper, the analytical and numerical calculations of this magnetic field are presented for the perfect metal and for gold. The amplitude and the phase transient curves between the known limiting cases of narrow and wide slits compared to the wavelength are found. The curve is shown to oscillate due to the emergence of new waveguide modes. The analytic solution for the perfect metal is in agreement with the computation for gold by means of the finite element method. The simple asymptotic formula for the light-induced attractive force is found in the limit of a narrow slit. PMID:27410865

  15. Rock magnetic properties of a soil developed on an alluvial deposit at Buttermilk Creek, Texas, USA

    NASA Astrophysics Data System (ADS)

    Lindquist, Anna K.; Feinberg, Joshua M.; Waters, Michael R.

    2011-12-01

    The evolution of magnetization within a floodplain soil begins with initial deposition of magnetic particles during sedimentation and continues via subsequent alteration and growth of iron-bearing compounds by pedogenic and biologic processes. Measurements of soil magnetic properties capture information about the developmental history of the soil and are a convenient method by which to investigate environmental change and pedogenesis. Using a range of magnetic measurements, a comprehensive scenario for soil development was constructed for floodplain sediments at the Debra L. Friedkin site, an important archeological site near Buttermilk Creek, Texas. Floodplain deposits have traditionally been avoided for soil magnetism studies because it is thought that the episodic input of sediment would form soils characterized by discrete sedimentary units rather than a continuous record of pedogenesis. We demonstrate that alluvial deposits can sometimes carry a straightforwardly interpretable magnetic signal similar to those typically seen in loess deposits. Smooth variation of rock magnetic parameters as a function of depth also leads us to conclude that the soil at this site is largely undisturbed and that the age of lithic artifacts found within the soil may be interpreted within stratigraphic context.

  16. Development of Wind-and-React Bi-2212 Accelerator Magnet Technology

    SciTech Connect

    Cheng, Daniel; Dietderich, Daniel R.; English, C.D.; Felice, Helene; Hannaford, Charles R.; Prestemon, Soren O.; Sabbi, GianLuca; Scanlan, Ron M.; Hikichi, Y.; Nishioka, J.; Hasegawa, T.; Godeke, A.

    2007-06-01

    We report on the progress in our R&D program, targeted to develop the technology for the application of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (Bi-2212) in accelerator magnets. The program uses subscale coils, wound from insulated cables, to study suitable materials, heat treatment homogeneity, stability, and effects of magnetic field and thermal and electro-magnetic loads. We have addressed material and reaction related issues and report on the fabrication, heat treatment, and analysis of subscale Bi-2212 coils. Such coils can carry a current on the order of 5000 A and generate, in various support structures, magnetic fields from 2.6 to 9.9 T. Successful coils are therefore targeted towards a hybrid Nb{sub 3}Sn-HTS magnet which will demonstrate the feasibility of Bi-2212 for accelerator magnets, and open a new magnetic field realm, beyond what is achievable with Nb{sub 3}Sn.

  17. Attribution, the Attractiveness Stereotype, and the Elderly.

    ERIC Educational Resources Information Center

    Johnson, Douglas F.; Pittenger, John B.

    1984-01-01

    Tests the applicability of the physical attractiveness stereotype to perceptions of the elderly. In the first study, college-age and elderly observers rated the attractiveness of faces of elderly people. In the second study, subjects rated faces at three levels of attractiveness on personality, success in life experiences, and occupational…

  18. Further developments relating to the NASA Langley Research Center 13-inch magnetic suspension and balance system

    NASA Technical Reports Server (NTRS)

    Britcher, Colin P.

    1991-01-01

    A few specific developments that were undertaken recently to the magnetic suspension and balance system (MSBS) are detailed. The improvements are as follows: modifications to the digital control system to accommodate a modified position sensing system; development of pressure telemetry systems; and revisions to the wind tunnel test section.

  19. A group's physical attractiveness is greater than the average attractiveness of its members: the group attractiveness effect.

    PubMed

    van Osch, Yvette; Blanken, Irene; Meijs, Maartje H J; van Wolferen, Job

    2015-04-01

    We tested whether the perceived physical attractiveness of a group is greater than the average attractiveness of its members. In nine studies, we find evidence for the so-called group attractiveness effect (GA-effect), using female, male, and mixed-gender groups, indicating that group impressions of physical attractiveness are more positive than the average ratings of the group members. A meta-analysis on 33 comparisons reveals that the effect is medium to large (Cohen's d = 0.60) and moderated by group size. We explored two explanations for the GA-effect: (a) selective attention to attractive group members, and (b) the Gestalt principle of similarity. The results of our studies are in favor of the selective attention account: People selectively attend to the most attractive members of a group and their attractiveness has a greater influence on the evaluation of the group. PMID:25733515

  20. Three-dimensional chiral skyrmions with attractive interparticle interactions.

    PubMed

    Leonov, A O; Monchesky, T L; Loudon, J C; Bogdanov, A N

    2016-09-01

    We introduce a new class of isolated three-dimensional skyrmion that can occur within the cone phase of chiral magnetic materials. These novel solitonic states consist of an axisymmetric core separated from the host phase by an asymmetric shell. These skyrmions attract one another. We derive regular solutions for isolated skyrmions arising in the cone phase of cubic helimagnets and investigate their bound states. PMID:27365366

  1. Three-dimensional chiral skyrmions with attractive interparticle interactions

    NASA Astrophysics Data System (ADS)

    Leonov, A. O.; Monchesky, T. L.; Loudon, J. C.; Bogdanov, A. N.

    2016-09-01

    We introduce a new class of isolated three-dimensional skyrmion that can occur within the cone phase of chiral magnetic materials. These novel solitonic states consist of an axisymmetric core separated from the host phase by an asymmetric shell. These skyrmions attract one another. We derive regular solutions for isolated skyrmions arising in the cone phase of cubic helimagnets and investigate their bound states.

  2. High Heels Increase Women's Attractiveness.

    PubMed

    Guéguen, Nicolas

    2015-11-01

    Research has found that the appearance of women's apparel helps increase their attractiveness as rated by men and that men care more about physical features in potential opposite-sex mates. However, the effect of sartorial appearance has received little interest from scientists. In a series of studies, the length of women's shoe heels was examined. A woman confederate wearing black shoes with 0, 5, or 9 cm heels asked men for help in various circumstances. In Study 1, she asked men to respond to a short survey on gender equality. In Study 2, the confederate asked men and women to participate in a survey on local food habit consumption. In Study 3, men and women in the street were observed while walking in back of the female confederate who dropped a glove apparently unaware of her loss. It was found that men's helping behavior increased as soon as heel length increased. However, heel length had no effect on women's helping behavior. It was also found that men spontaneously approached women more quickly when they wore high-heeled shoes (Study 4). Change in gait, foot-size judgment, and misattribution of sexiness and sexual intent were used as possible explanations. PMID:25408499

  3. Attracting Girls into Physics (abstract)

    NASA Astrophysics Data System (ADS)

    Gadalla, Afaf

    2009-04-01

    A recent international study of women in physics showed that enrollment in physics and science is declining for both males and females and that women are severely underrepresented in careers requiring a strong physics background. The gender gap begins early in the pipeline, from the first grade. Girls are treated differently than boys at home and in society in ways that often hinder their chances for success. They have fewer freedoms, are discouraged from accessing resources or being adventurous, have far less exposure to problem solving, and are not encouraged to choose their lives. In order to motivate more girl students to study physics in the Assiut governorate of Egypt, the Assiut Alliance for the Women and Assiut Education District collaborated in renovating the education of physics in middle and secondary school classrooms. A program that helps in increasing the number of girls in science and physics has been designed in which informal groupings are organized at middle and secondary schools to involve girls in the training and experiences needed to attract and encourage girls to learn physics. During implementation of the program at some schools, girls, because they had not been trained in problem-solving as boys, appeared not to be as facile in abstracting the ideas of physics, and that was the primary reason for girls dropping out of science and physics. This could be overcome by holding a topical physics and technology summer school under the supervision of the Assiut Alliance for the Women.

  4. Development of a 1.8 T permanent magnet wiggler system (abstract)

    NASA Astrophysics Data System (ADS)

    Robinson, K. E.; Gottschalk, S. C.; Jander, D. R.; Quimby, D. C.; Valla, A. S.

    1995-02-01

    The design, development, and realization of a 1.8 T permanent magnet hybrid wiggler system is presented. This 3.0 m wiggler has a 200 mm period, operating at a minimum gap of 22 mm. It has 27 poles and integrated end correctors and field clamps. The magnetic design for this device is pushed to a regime where few hybrid devices have operated. The very large peak field causes a significant increase in the saturation of the vanadium permendur poles. The operating point also significantly impacts the transverse uniformity of the field and the magnet operating point. The magnetic design approach and the development of a mechanical structure which provides adequate strength and stability are discussed. The system is a complete stand-alone system with a fully integrated controls system and complete insertion device magnetics measurement system. The adjustment of the end compensation of the device with the presence of the field clamps requires particular attention. The distinctive elements of the design and the result of the magnetic and mechanical testing of the device are presented. This wiggler is being delivered to the Synchrotron Radiation Research Center for installation at the beginning of 1995.

  5. Developed turbulence and nonlinear amplification of magnetic fields in laboratory and astrophysical plasmas

    PubMed Central

    Meinecke, Jena; Tzeferacos, Petros; Bell, Anthony; Bingham, Robert; Clarke, Robert; Churazov, Eugene; Crowston, Robert; Doyle, Hugo; Drake, R. Paul; Heathcote, Robert; Koenig, Michel; Kuramitsu, Yasuhiro; Kuranz, Carolyn; Lee, Dongwook; MacDonald, Michael; Murphy, Christopher; Notley, Margaret; Park, Hye-Sook; Pelka, Alexander; Ravasio, Alessandra; Reville, Brian; Sakawa, Youichi; Wan, Willow; Woolsey, Nigel; Yurchak, Roman; Miniati, Francesco; Schekochihin, Alexander; Lamb, Don; Gregori, Gianluca

    2015-01-01

    The visible matter in the universe is turbulent and magnetized. Turbulence in galaxy clusters is produced by mergers and by jets of the central galaxies and believed responsible for the amplification of magnetic fields. We report on experiments looking at the collision of two laser-produced plasma clouds, mimicking, in the laboratory, a cluster merger event. By measuring the spectrum of the density fluctuations, we infer developed, Kolmogorov-like turbulence. From spectral line broadening, we estimate a level of turbulence consistent with turbulent heating balancing radiative cooling, as it likely does in galaxy clusters. We show that the magnetic field is amplified by turbulent motions, reaching a nonlinear regime that is a precursor to turbulent dynamo. Thus, our experiment provides a promising platform for understanding the structure of turbulence and the amplification of magnetic fields in the universe. PMID:26100873

  6. Developed turbulence and nonlinear amplification of magnetic fields in laboratory and astrophysical plasmas.

    PubMed

    Meinecke, Jena; Tzeferacos, Petros; Bell, Anthony; Bingham, Robert; Clarke, Robert; Churazov, Eugene; Crowston, Robert; Doyle, Hugo; Drake, R Paul; Heathcote, Robert; Koenig, Michel; Kuramitsu, Yasuhiro; Kuranz, Carolyn; Lee, Dongwook; MacDonald, Michael; Murphy, Christopher; Notley, Margaret; Park, Hye-Sook; Pelka, Alexander; Ravasio, Alessandra; Reville, Brian; Sakawa, Youichi; Wan, Willow; Woolsey, Nigel; Yurchak, Roman; Miniati, Francesco; Schekochihin, Alexander; Lamb, Don; Gregori, Gianluca

    2015-07-01

    The visible matter in the universe is turbulent and magnetized. Turbulence in galaxy clusters is produced by mergers and by jets of the central galaxies and believed responsible for the amplification of magnetic fields. We report on experiments looking at the collision of two laser-produced plasma clouds, mimicking, in the laboratory, a cluster merger event. By measuring the spectrum of the density fluctuations, we infer developed, Kolmogorov-like turbulence. From spectral line broadening, we estimate a level of turbulence consistent with turbulent heating balancing radiative cooling, as it likely does in galaxy clusters. We show that the magnetic field is amplified by turbulent motions, reaching a nonlinear regime that is a precursor to turbulent dynamo. Thus, our experiment provides a promising platform for understanding the structure of turbulence and the amplification of magnetic fields in the universe. PMID:26100873

  7. Parallel Path Magnet Motor: Development of the Theoretical Model and Analysis of Experimental Results

    NASA Astrophysics Data System (ADS)

    Dirba, I.; Kleperis, J.

    2011-01-01

    Analytical and numerical modelling is performed for the linear actuator of a parallel path magnet motor. In the model based on finite-element analysis, the 3D problem is reduced to a 2D problem, which is sufficiently precise in a design aspect and allows modelling the principle of a parallel path motor. The paper also describes a relevant numerical model and gives comparison with experimental results. The numerical model includes all geometrical and physical characteristics of the motor components. The magnetic flux density and magnetic force are simulated using FEMM 4.2 software. An experimental model has also been developed and verified for the core of switchable magnetic flux linear actuator and motor. The results of experiments are compared with those of theoretical/analytical and numerical modelling.

  8. Development of Laser-Polarized Noble Gas Magnetic Resonance Imaging (MRI) Technology

    NASA Technical Reports Server (NTRS)

    Walsworth, Ronald L.

    2004-01-01

    We are developing technology for laser-polarized noble gas nuclear magnetic resonance (NMR), with the aim of enabling it as a novel biomedical imaging tool for ground-based and eventually space-based application. This emerging multidisciplinary technology enables high-resolution gas-space magnetic resonance imaging (MRI)-e.g., of lung ventilation, perfusion, and gas-exchange. In addition, laser-polarized noble gases (3He and 1BXe) do not require a large magnetic field for sensitive NMR detection, opening the door to practical MRI with novel, open-access magnet designs at very low magnetic fields (and hence in confined spaces). We are pursuing two specific aims in this technology development program. The first aim is to develop an open-access, low-field (less than 0.01 T) instrument for MRI studies of human gas inhalation as a function of subject orientation, and the second aim is to develop functional imaging of the lung using laser-polarized He-3 and Xe-129.

  9. [Sandwich type dental magnetic devices of Nd-Fe-B magnet and permendur].

    PubMed

    Okuno, O; Nakano, T; Hamanaka, H; Kinouchi, Y

    1989-07-01

    Nd-Fe-B magnets have a very high maximum energy product (BH max), which is defined as the attractive strength between a magnet and opposing magnetic materials. Permendur (Fe-49 Co-2 V) has the greatest magnetic saturation (Bs), which makes it strongly magnetized. If magnetic retainers were made with Nd-Fe-B magnets and a permendur yoke, they would be small and have strong retention. The purpose of this investigation was to develop small dental magnetic devices with Nd-Fe-B magnets and permendur yokes. The magnetic devices form sandwich-type magnetic circuits with magnetic stainless steel keepers. A 4 x 3 x 2 mm rectangular prism Nd-Fe-B magnet was used. The magnet was sandwitched between the semi-columnar yokes. To protect the magnet from corrosion, the devices were encapsulated with 304 stainless steel by silver brazing and adhesion bonding of a stainless steel tube and foil. The optimum cross-sectional area of the yoke was determined experimentally. The dimensions of the devices were phi 5 x 3.5 mm for 4 x 3 x 2 magnet. The breakaway retention for a keeper of magnetic stainless steel (Type XM 27) was 852 g on average. This breakaway retention is sufficient for dental prosthetic applications. PMID:2491164

  10. Development of a 22,000 RPM magnetic bearing system for the SSME HPOTP

    SciTech Connect

    Artinian, V.

    1995-12-31

    The design, fabrication, and testing of a permanent magnet bias, homopolar radial magnetic bearing is described. The current flight version of the SSME HPOTP (Space Shuttle Main Engine High Pressure Oxygen Turbo Pump) was used as a baseline, to define the magnetic bearing performance requirements. The HPOTP magnetic bearing system is a full five axis levitation support system with two 1,800 pound load capacity radial bearings and one 300 pound thrust bearing. The system is designed to operate at 22,000 rpm, in a cryogenic temperature of {minus}321{degrees}F. A rotordynamic model for a magnetic bearing version of the HPOTP was developed to determine the static and dynamic loads on the bearing. The electromechanical design followed a parametric analysis, performed with AVCON`s magnetic bearing program PERAMCON and magnetic Finite Element Analysis (FEA) software. The use of three different materials on the rotor (9% nickel, stainless steel, and cobalt steel) required extensive stress and thermal analysis to ensure the interference fits were maintained during operation at 22,000 rpm and {minus}300{degrees}F. The rotordynamic stability analysis of the coupled rotor/housing/bearing system also provided the controller transfer function. An AVCON developed digital controller was utilized to implement the transfer function and control algorithm. AVCON proprietary sensors for position input and pulse-width modulated (PWM) power amplifiers for output were also implemented in the system. A HPOTP simulator test rig was designed and built to perform operational and partial load testing of the bearings at cryogenic temperatures and spin speeds up to 20,000 rpm. Fabrication of the HPOTP simulator with magnetic bearings was completed at the end of 1994. Testing of the HPOTP simulator is ongoing.

  11. Response of Lucilia sericata (Diptera: Calliphoridae) to Screwworm Oviposition Attractant.

    PubMed

    Chaudhury, M F; Zhu, J J; Skoda, S R

    2015-07-01

    The sheep blowfly, Lucilia sericata Meigen (Diptera: Calliphoridae), causes sheep myiasis in various parts of the world. Female flies are attracted to sheep following various olfactory cues emanating from the sheep's body, and oviposit on suitable substrates on sheep ultimately causing myiasis. Earlier workers attempted to reduce fly population in the field, with some success, using traps baited with various attractants. This research was conducted to determine if L. sericata would respond to a recently developed synthetic attractant that has attracted gravid screwworms, Cochliomyia hominivorax Coquerel, and stimulated them to oviposit. Results of the laboratory bioassays demonstrated that gravid females L. sericata were attracted to substrates treated with the synthetic screwworm attractant composed of five compounds--dimethyl disulfide, dimethyl trisulfide, phenol, p-cresol, and indole. Tests with various combinations of these compounds suggest that the sulfur compounds and indole are the most important compounds to elicit attraction and stimulate oviposition, while phenol and p-cresol may have minor roles. Semiochemical baits based on these compounds may be useful in the field to trap gravid L. sericata. PMID:26335458

  12. Effects of Instructor Attractiveness on Learning.

    PubMed

    Westfall, Richard; Millar, Murray; Walsh, Mandy

    2016-01-01

    Although a considerable body of research has examined the impact of student attractiveness on instructors, little attention has been given to the influence of instructor attractiveness on students. This study tested the hypothesis that persons would perform significantly better on a learning task when they perceived their instructor to be high in physical attractiveness. To test the hypothesis, participants listened to an audio lecture while viewing a photograph of instructor. The photograph depicted either a physically attractive instructor or a less attractive instructor. Following the lecture, participants completed a forced choice recognition task covering material from the lecture. Consistent with the predictions; attractive instructors were associated with more learning. Finally, we replicated previous findings demonstrating the role attractiveness plays in person perception. PMID:27410051

  13. Origin and magnetic properties of soil profiles developed on different geological bedrock

    NASA Astrophysics Data System (ADS)

    Szuszkiewicz, Marcin; Magiera, Tadeusz; Łukasik, Adam; Wawer, Małgorzata; Mendakiewicz, Maria

    2014-05-01

    Soil magnetic susceptibility anomaly is a result of accumulation in soil profile magnetic minerals (mostly iron oxides and hydroxides) of both natural and anthropogenic origin. The proper interpretation of magnetic susceptibility distribution in soil profile needs the information about magnetic properties of particles present in, respectively geological bedrock, subsoil horizons and topsoils horizons. The study was aimed on characterization mineralogical composition as well as physicochemical properties of mineral soil horizons. The essence of these research is to show, with the application of magnetic measurements, the character and diversification of selected rocks types and its influence on magnetic properties in soil profiles, in the local scale. The collected rock material included some sedimentary, igneous rocks (i.e. plutonic and volcanic) and metamorphic rocks, occurring in Poland. Magnetic properties of bedrock and soil samples were determined according to the measurements of mass magnetic susceptibility (Ξ) and thermomagnetic curves. Technogenic character and nature of research sites of magnetic susceptibility anomalies, was distinctly observed only in the uppermost part of soil profiles. Except the anthropogenic peak of magnetic susceptibility observed in organic soil horizons, the vertical distribution of Ξ in the whole soil profiles developed on sedimentary rocks is relatively low values ranging from ~0.5 to 75 ×10-8m3kg-1. In some studied profiles noticeable Ξ value increment is observed in subsoil horizons, revealing pedogenic character of magnetic susceptibility (influence of soil forming process - presence of superparamagnetic particles). Analyses of thermomagnetic curves support the presence of pedogenic iron minerals in subsoil horizons. The strong geogenic character with increasing Ξ values downward the soil profile was observed in soils developed on basalt, serpentinite, gabbro and andesite rocks. Here the Ξ value measured in the bedrock

  14. Develop and test an Internally Cooled, Cabled Superconductor (ICCS) for large scale MHD magnets: Analysis report

    NASA Astrophysics Data System (ADS)

    Hatch, A. M.; Marston, P. G.; Tarrh, J. M.; Becker, H.; Dawson, A. M.; Minervini, J. V.

    1986-01-01

    A three-year program to develop and test an internally-cooled cabled superconductor (ICCS) for large-scale MHD magnets is being performed by MIT for the Pittsburgh Energy Technology Center (PETC) under contract DE-AC22-84PC70512. Included in this report are electromagnetic, thermodynamic, structural, protection, and systems analyses, completed as required to substantiate the preliminary conductor design requirements definition and the associated preconceptual magnet design developed in Task 1. Copper-stabilized NbTi superconductor was selected at the outset as being most suitable for the application. The analysis necessary to substantiate the preconceptual MHD magnet design is complete, including field and force calculations, preliminary structural analysis, thermodynamic (cryogenic) analysis, and the analysis of the magnet electrical and protective systems. A significant result of the field analysis is the determination that maximum fields to which the conductor is exposed in the magnet are considerably higher than originally expected. Changes were made to produce a revised design in which the maximum field is 6.9T (53% above central field) and adequate stability is ensured. Analysis necessary to substantiate a preliminary conductor design requirement definition for full-scale conductor has been completed except that further work is required to establish maximum allowable internal flow resistance and maximum length between vents. Procedures for accomplishing these analyses have already been developed at MIT and by other contractors.

  15. Development of forced flow cooled current leads for fusion magnets

    NASA Astrophysics Data System (ADS)

    Heller, R.; Fink, S.; Friesinger, G.; Kienzler, A.; Lingor, A.; Schleinkofer, G.; Süßer, M.; Ulbricht, A.; Wüchner, F.; Zahn, G.

    2001-03-01

    During the past 15 years, the Institut für Technische Physik of the Forschungszentrum Karlsruhe, Germany, has developed current leads cooled by forced-flow supercritical helium in the current range from 20 to 80 kA. The design is based on a separation of the current carrying part and the heat exchanger part as well as the presence of the so-called superconductor inserts made of Nb 3Sn wires inside the conductor in the heat exchanger area which allows the operation of the current lead at minimum helium mass flow in a wide current range. The paper describes the design and construction of the current leads as well as operation results obtained during various tests performed in the coil test facility TOSKA at the Forschungszentrum Karlsruhe.

  16. Application and development of advanced Lorentz microscopy techniques for the study of magnetic nanostructures

    NASA Astrophysics Data System (ADS)

    Beacham, Robert J.

    This PhD project presents an investigation into the development of magnetic imaging methods in the TEM and their application in imaging narrow domain walls in multilayer magnetic structures. Lorentz microscopy techniques are limited in quantitative magnetic imaging as this generally requires using scanning imaging modes which limits the capability of imaging dynamic processes. The first imaging method developed in this study is a phase gradient technique with the aim of producing quantitative magnetic contrast proportional to the magnetic induction of the sample whilst maintaining a live imaging mode. This method uses a specifically engineered, semi-electron-transparent graded wedge aperture to controllably perturb intensity in the back focal plane. The results of this study found that this method could produce magnetic contrast proportional to the sample induction, however the required gradient of the wedge aperture made this contrast close to the noise level with large associated errors. In the second part of this study we investigated the development of a technique aimed at gaining sub-microsecond temporal resolution within TEMs based on streak imaging. We are using ramped pulsed magnetic fields, applied across nanowire samples to both induce magnetic behaviour and detect the electron beam across the detector with respect to time. We are coupling this with a novel pixelated detector on the TEM in the form of a Medipix/Timepix chip capable of microsecond exposure times without adding noise. Running this detector in integral mode and allowing for practical limitations such as experiment time and aperture stability, the resultant streak images were taken in Fresnel, Foucault and low angle diffraction imaging modes. We found that while this method is theoretically viable, the limiting factor was the contrast of the magnetic signal in the streak and therefore the total image counts. Domain walls (DWs) in synthetic antiferromagnetically (SAF) coupled films patterned

  17. WInd-and-react Bi-2212 coil development for accelerator magnets

    SciTech Connect

    Godeke, A.; Acosta, P.; Cheng, D.; Dietderich, D. R.; Mentink, M. G. T.; Prestemon, S. O.; Meinesz, M.; Hong, S.; Huang, Y.; Miao, H.; Parrell, J.; Sabbi, G.L.

    2009-10-13

    Sub-scale coils are being manufactured and tested at Lawrence Berkeley National Laboratory in order to develop wind-and-react Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (Bi-2212) magnet technology for future graded accelerator magnet use. Previous Bi-2212 coils showed significant leakage of the conductors core constituents to the environment, which can occur during the partial melt reaction around 890 C in pure oxygen. The main origin of the observed leakage is intrinsic leakage of the wires, and the issue is therefore being addressed at the wire manufacturing level. We report on further compatibility studies, and the performance of new sub-scale coils that were manufactured using improved conductors. These coils exhibit significantly reduced leakage, and carry currents that are about 70% of the witness wire critical current (I{sub c}). The coils demonstrate, for the first time, the feasibility of round wire Bi-2212 conductors for accelerator magnet technology use. Successful high temperature superconductor coil technology will enable the manufacture of graded accelerator magnets that can surpass the, already closely approached, intrinsic magnetic field limitations of Nb-based superconducting magnets.

  18. Development of a Split Bitter-type Magnet System for Dusty Plasma Experiments

    NASA Astrophysics Data System (ADS)

    Bates, Evan; Romero-Talamas, Carlos A.; Birmingham, William J.; Rivera, William F.

    2014-10-01

    A 10 Tesla Bitter-type magnetic system is under development at the Dusty Plasma Laboratory of the University of Maryland, Baltimore County (UMBC). We present here an optimization technique that uses differential evolution to minimize the omhic heating produced by the coils, while constraining the magnetic field in the experimental volume. The code gives us the optimal dimensions for the coil system including: coil length, turn thickness, disks radii, resistance, and total current required for a constant magnetic field. Finite element parametric optimization is then used to establish the optimal design for water cooling holes. Placement of the cooling holes will also take into consideration the magnetic forces acting on the copper alloy disks to ensure the material strength is not compromised during operation. The proposed power and cooling water delivery subsystems for the coils are also presented. Upon completion and testing of the magnet system, planned experiments include the propagation of magnetized waves in dusty plasma crystals under various boundary conditions, and viscosity in rotational shear flow, among others.

  19. Development of a Process to Build Polyimide Insulated Magnets For Operation at 350C

    SciTech Connect

    Zatz, Irving J.

    2013-07-09

    An extensive R&D program has been conducted that has confirmed the feasibility of designing and fabricating copper alloy magnets that can successfully operate at temperatures as high as 350C. The process, originally developed for the possibility of manufacturing in-vessel resonant magnetic field perturbation (RMP) coils for JET, has been optimized for insulated magnet (and, potentially, other high temperature component) applications. One of the benefits of high temperature operation is that active cooling may no longer be required, greatly simplifying magnet/component design. These elevated temperatures are beyond the safe operating limits of conventional OFHC copper and the epoxies that bond and insulate the turns of typical magnets. This would necessitate the use an alternative copper alloy conductor such as C18150 (CuCrZr). Coil manufacture with polyimide is very similar to conventional epoxy bonded coils. Conductors would be dry wound then impregnated with polyimide of low enough viscosity to permit saturation, then cured; similar to the vacuum pressure impregnation process used for conventional epoxy bonded coils. Representative polyimide insulated coils were mechanically tested at both room temperature and 350C. Mechanical tests included turn-to-turn shear bond strength and overall polyimide adhesion strength, as well as the flexural strength of a 48-turn polyimide-bonded coil bundle. This paper will detail the results of the testing program on coil samples. These results demonstrate mechanical properties as good, or better than epoxy bonded magnets, even at 350C.

  20. Roles of Magnetic Reconnection and Developments of Modern Theory^*

    NASA Astrophysics Data System (ADS)

    Coppi, B.

    2007-11-01

    The role of reconnection was recognized in Solar and Space Physics and auroral substorms were suggested to originate in the night-side of the Earth's magnetosphere as a result collisionless reconnectionootnotetextB. Coppi, Nature 205, 998 (1965). well before the kind of modern theory employed for this became applied to laboratory plasmas. Experiments have reached low collisionality regimes where, like in space plasmas, the features of the electron distribution and in particular of the electron temperature gradient become important and the factors contributing to the electron thermal energy balance equation (transverse thermal and longitudinal diffusivities, or electron Landau dampingootnotetextB. Coppi, J.W.-K. Mark, L. Sugiyama, G. Bertin, Phys. Rev. Letters 42, 1058 (1978) and J. Drake, et al., Phys. Fluids 26, 2509 (1983). play a key role. For this an asymptotic theory of modes producing macroscopic islands has been developed involving 3 regions, the innermost one related to finite resistivity and the intermediate one to the finite ratio of the to thermal conductivitiesootnotetextB. Coppi, C. Crabtree, and V. Roytershteyn contribution to Paper TH/R2-19, I.A.E.A. Conference 2006.,^4. A background of excited micro-reconnecting modes, driven by the electron temperature gradient, is considered to make this ratio significantootnotetextB. Coppi, in``Collective Phenomena in Macroscopic Systems'' Eds. G. Bertin et al. (World Scientific, 2007) MIT-LNS Report 06/11(2006). ^*Supported in part by the US D.O.E.

  1. Magnetic and geochemical characterization of Andosols developed on basalts in the Massif Central, France

    NASA Astrophysics Data System (ADS)

    Grison, Hana; Petrovsky, Eduard; Stejskalova, Sarka; Kapicka, Ales

    2015-05-01

    Identification of Andosols is primarily based upon the content of their colloidal constituents—clay and metal-humus complexes—and on the determining of andic properties. This needs time and cost-consuming geochemical analyses. Our primary aim of this study is to describe the magnetic and geochemical properties of soils rich in iron oxides derived from strongly magnetic volcanic basement (in this case Andosols). Secondary aim is to explore links between magnetic and chemical parameters of andic soils with respect to genesis factors: parent material age, precipitation, and thickness of the soil profile. Six pedons of andic properties, developed on basaltic lavas, were analyzed down to parent rock by a set of magnetic and geochemical methods. Magnetic data of soil and rock samples reflect the type, concentration, and particle-size distribution of ferrimagnetic minerals. Geochemical data include soil reaction (pH in H2O), cation exchange capacity, organic carbon, and different forms of extractable iron and aluminum content. Our results suggest the following: (1) magnetic measurements of low-field mass-specific magnetic susceptibility can be a reliable indicator for estimating andic properties, and in combination with thermomagnetic curves may be suitable for discriminating between alu-andic and sil-andic subtypes. (2) In the studied Andosols, strong relationships were found between (a) magnetic grain-size parameters, precipitation, and exchangeable bases; (b) concentration of ferrimagnetic particles and degree of crystallization of free iron; and (c) parameters reflecting changes in magneto-mineralogy and soil genesis (parent material age + soil depth).

  2. Development of a SQUID (Superconducting Quantum Interference Device) detection system of magnetic nanoparticles for cancer imaging

    NASA Astrophysics Data System (ADS)

    Ge, Song

    In this dissertation, I present the development of a SQUID (Superconducting Quantum Interference Device) imaging system using targeted magnetic nanoparticles (NPs) as contrast agents. The contrast agents are functionalized for targeting by the conjugation of the magnetic NPs to folic acid (FA) molecules on dendrimer scaffolds. Cellular internalization is accomplished through the high-affinity folic acid receptors (FARs), which are overexpressed in various human carcinomas. SQUID can be applied to detect signals from the magnetic cores of the contrast agents and hence diagnose the tumor. Based on the magnetic properties of the magnetic NPs, two detection methods were developed: remanence and magnetorelaxometry (MRX). The remanence measurement-based method detects magnetic NPs that are sufficiently large and possess long relaxation time. Samples were vertically oscillated and horizontally translated each in one-dimension. The system was calibrated with gamma-Fe2O3 NPs (mean diameter 25 nm) and the detection limit was found to be 10 ng at a distance of 1.7 cm and the spatial resolution was ˜1 cm. A theoretical model of this system was proposed and applied to image reconstruction of scanned phantoms with two NP injection spots. The developed SQUID system can determine not only the amount and horizontal position of the NPs, but also their depth in the phantoms. The MRX technique utilizes the NPs superparamagnetic property and records their time course magnetic decay. The system was investigated by using a number of iron oxide NP products with different mean diameters. The results showed that the MRX signal intensity is sensitively dependent on the size of the NPs. The best detection limit of 300 ng of total iron content was found on using a d = 12 nm Fe3O4 NP sample and this result was supported by computer simulations. To produce magnetic NPs for the MRX study, a synthetic approach of size-controllable Fe3O4 NPs was developed. Accordingly, the magnetic property can be

  3. Miscalibrations in judgements of attractiveness with cosmetics.

    PubMed

    Jones, Alex L; Kramer, Robin S S; Ward, Robert

    2014-10-01

    Women use cosmetics to enhance their attractiveness. How successful they are in doing so remains unknown--how do men and women respond to cosmetics use in terms of attractiveness? There are a variety of miscalibrations where attractiveness is concerned--often, what one sex thinks the opposite sex finds attractive is incorrect. Here, we investigated observer perceptions about attractiveness and cosmetics, as well as their understanding of what others would find attractive. We used computer graphic techniques to allow observers to vary the amount of cosmetics applied to a series of female faces. We asked observers to optimize attractiveness for themselves, for what they thought women in general would prefer, and what they thought men in general would prefer. We found that men and women agree on the amount of cosmetics they find attractive, but overestimate the preferences of women and, when considering the preferences of men, overestimate even more. We also find that models' self-applied cosmetics are far in excess of individual preferences. These findings suggest that attractiveness perceptions with cosmetics are a form of pluralistic ignorance, whereby women tailor their cosmetics use to an inaccurate perception of others' preferences. These findings also highlight further miscalibrations of attractiveness ideals. PMID:24670156

  4. World Digital Magnetic Anomaly Map, development towards the Second Edition. (Invited)

    NASA Astrophysics Data System (ADS)

    Korhonen, J. V.

    2009-12-01

    Magnetic anomalies are small deviations in the Earth’s main magnetic field, caused by variation of magnetization in the uppermost lithosphere. Magnetic anomalies provide spatial key information for understanding the structure and evolution of the Earths crust. In practice these anomalies are used e.g. for assessment and prospecting of geological natural resources and planning of land use. A common way to calculate a magnetic anomaly value has been to subtract International Geomagnetic Reference Field (IGRF) from a total field measurement that is cleaned from short term variation of the Earth's magnetic field. World Digital Magnetic Anomaly Map (WDMAM) is a collaborative project between member organizations of International Association of Geomagnetism and Aeronomy (IAGA) and the Commission for Geological Map of the World (CGMW). The First Edition of the map was published in 2007. It consisted of a paper map 1:50 Million and a 3 minutes global grid of total field anomalies at an altitude of 5 km above the geoid. The First Edition was aimed to compile as much as possible available land and sea magnetic data, and homogenize it by comparing anomalies with a satellite magnetic lithospheric field model. This first version was prepared in a tight schedule, to show the usefulness of the map to the community and to form a basis for later development and future editions of the map. Hence, much was left to be improved for the second edition, including sparse coverage in two continents and all southern seas. The satellite models were understood to gain more detail in near future when the CHAMP-satellite would reach lower orbits, and hence higher resolution. The SWARM-satellite constellation was seen to produce even more suitable data in a few years thereafter. Ocean magnetic data sets required careful processing and leveling. The method of homogenization of anomalies included replacing long wavelength information by satellite model spectral data, and hence rejecting

  5. Development and Testing of a Magnetically Actuated Capsule Endoscopy for Obesity Treatment

    PubMed Central

    Do, Thanh Nho; Seah, Tian En Timothy; Yu, Ho Khek; Phee, Soo Jay

    2016-01-01

    Intra-gastric balloons (IGB) have become an efficient and less invasive method for obesity treatment. The use of traditional IGBs require complex insertion tools and flexible endoscopes to place and remove the balloon inside the patient’s stomach, which may cause discomfort and complications to the patient. This paper introduces a new ingestible weight-loss capsule with a magnetically remote-controlled inflatable and deflatable balloon. To inflate the balloon, biocompatible effervescent chemicals are used. As the source of the actuation is provided via external magnetic fields, the magnetic capsule size can be significantly reduced compared to current weight-loss capsules in the literature. In addition, there are no limitations on the power supply. To lose weight, the obese subject needs only to swallow the magnetic capsule with a glass of water. Once the magnetic capsule has reached the patient’s stomach, the balloon will be wirelessly inflated to occupy gastric space and give the feeling of satiety. The balloon can be wirelessly deflated at any time to allow the magnetic capsule to travel down the intestine and exit the body via normal peristalsis. The optimal ratio between the acid and base to provide the desired gas volume is experimentally evaluated and presented. A prototype capsule (9.6mm x 27mm) is developed and experimentally validated in ex-vivo experiments. The unique ease of delivery and expulsion of the proposed magnetic capsule is slated to make this development a good treatment option for people seeking to lose excess weight. PMID:26815309

  6. Recent developments in Liquid Phase Electroepitaxial growth of bulk crystals under magnetic field

    NASA Astrophysics Data System (ADS)

    Dost, Sadik; Lent, Brian; Sheibani, Hamdi; Liu, Yongcai

    2004-05-01

    This review article presents recent developments in Liquid Phase Electroepitaxial (LPEE) growth of bulk single crystals of alloy semiconductors under an applied static magnetic field. The growth rate in LPEE is proportional to the applied electric current. However, at higher electric current levels the growth becomes unstable due to the strong convection occurring in the liquid zone. In order to address this problem, a significant body of research has been performed in recent years to suppress and control the natural convection for the purpose of prolonging the growth process to grow larger crystals. LPEE growth experiments show that the growth rate under an applied static magnetic field is also proportional and increases with the field intensity level. The modeling of LPEE growth under magnetic field was also the subject of interest. Two-dimensional mathematical models developed for the LPEE growth process predicted that the natural convection in the liquid zone would be suppressed almost completely with increasing the magnetic field level. However, experiments and also three-dimensional models have shown that there is an optimum magnetic field level below which the growth process is stable and the convection in the liquid zone is suppressed, but above such a field level the convective flow becomes very strong and leads to unstable growth with unstable interfaces. To cite this article: S. Dost et al., C. R. Mecanique 332 (2004).

  7. House Fly (Musca domestica L.) Attraction to Insect Honeydew.

    PubMed

    Hung, Kim Y; Michailides, Themis J; Millar, Jocelyn G; Wayadande, Astri; Gerry, Alec C

    2015-01-01

    House flies are of major concern as vectors of food-borne pathogens to food crops. House flies are common pests on cattle feedlots and dairies, where they develop in and feed on animal waste. By contacting animal waste, house flies can acquire human pathogenic bacteria such as Escherichia coli and Salmonella spp., in addition to other bacteria, viruses, or parasites that may infect humans and animals. The subsequent dispersal of house flies from animal facilities to nearby agricultural fields containing food crops may lead to pre-harvest food contamination with these pathogens. We hypothesized that odors from honeydew, the sugary excreta produced by sucking insects feeding on crops, or molds and fungi growing on honeydew, may attract house flies, thereby increasing the risk of food crop contamination. House fly attraction to honeydew-contaminated plant material was evaluated using a laboratory bioassay. House flies were attracted to the following plant-pest-honeydew combinations: citrus mealybug on squash fruit, pea aphid on faba bean plants, whitefly on navel orange and grapefruit leaves, and combined citrus mealybug and cottony cushion scale on mandarin orange leaves. House flies were not attracted to field-collected samples of lerp psyllids on eucalyptus plants or aphids on crepe myrtle leaves. Fungi associated with field-collected honeydews were isolated and identified for further study as possible emitters of volatiles attractive to house flies. Two fungal species, Aureobasidium pullulans and Cladosporium cladosporioides, were repeatedly isolated from field-collected honeydew samples. Both fungal species were grown in potato dextrose enrichment broth and house fly attraction to volatiles from these fungal cultures was evaluated. House flies were attracted to odors from A. pullulans cultures but not to those of C. cladosporioides. Identification of specific honeydew odors that are attractive to house flies could be valuable for the development of improved house

  8. House Fly (Musca domestica L.) Attraction to Insect Honeydew

    PubMed Central

    Hung, Kim Y.; Michailides, Themis J.; Millar, Jocelyn G.; Wayadande, Astri; Gerry, Alec C.

    2015-01-01

    House flies are of major concern as vectors of food-borne pathogens to food crops. House flies are common pests on cattle feedlots and dairies, where they develop in and feed on animal waste. By contacting animal waste, house flies can acquire human pathogenic bacteria such as Escherichia coli and Salmonella spp., in addition to other bacteria, viruses, or parasites that may infect humans and animals. The subsequent dispersal of house flies from animal facilities to nearby agricultural fields containing food crops may lead to pre-harvest food contamination with these pathogens. We hypothesized that odors from honeydew, the sugary excreta produced by sucking insects feeding on crops, or molds and fungi growing on honeydew, may attract house flies, thereby increasing the risk of food crop contamination. House fly attraction to honeydew-contaminated plant material was evaluated using a laboratory bioassay. House flies were attracted to the following plant-pest-honeydew combinations: citrus mealybug on squash fruit, pea aphid on faba bean plants, whitefly on navel orange and grapefruit leaves, and combined citrus mealybug and cottony cushion scale on mandarin orange leaves. House flies were not attracted to field-collected samples of lerp psyllids on eucalyptus plants or aphids on crepe myrtle leaves. Fungi associated with field-collected honeydews were isolated and identified for further study as possible emitters of volatiles attractive to house flies. Two fungal species, Aureobasidium pullulans and Cladosporium cladosporioides, were repeatedly isolated from field-collected honeydew samples. Both fungal species were grown in potato dextrose enrichment broth and house fly attraction to volatiles from these fungal cultures was evaluated. House flies were attracted to odors from A. pullulans cultures but not to those of C. cladosporioides. Identification of specific honeydew odors that are attractive to house flies could be valuable for the development of improved house

  9. Physician equity alliances: attractive alternatives to PHOs.

    PubMed

    Goldstein, D

    1997-04-01

    Physician equity alliances are becoming attractive alternatives to PHOs as integrative models for partnering with physicians, securing managed care contracts and increasing revenue. Unlike many PHOs, these alliances provide mechanisms for asset integration and long-term relationships along with utilization management, sophisticated information systems, access to capital and opportunities for physicians to integrate clinically. There are six major types of physician equity alliances: majority physician-owned, clinic without walls, health system joint venture, publicly held physician practice management company, specialty network, and venture capital. The type of alliance that a physician group practice ultimately develops depends on vision, values, method of capitalization, initial organizer of the alliance, level of involvement of physicians in business issues, corporate structure desired, and characteristics of the managed care market in which the alliance will operate. PMID:10166285

  10. Floral scent of Canada thistle, and its potential as a generic insect attractant

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The flowers of Canada thistles, Cirsium arvense (L.)attract a wide range of insects including pollinators and herbivorous species. This attraction is primarily mediated by floral odor, which offers potential for developing generic insect attractants based on odor. In this study we have analyzed the ...

  11. Development of Interior Permanent Magnet Motors Reducing Harmonic Iron Losses under Field Weakening Control

    NASA Astrophysics Data System (ADS)

    Yamazaki, Katsumi; Ohki, Shunji; Nezu, Akira; Ikemi, Takeshi

    In this paper, we present the development of interior magnet motors reducing iron loss at high rotational speed under the flux weakening control. The rotor core and magnet shapes are determined by the automatic numerical calculation using combination of the optimization method and the adaptive finite element method. The optimized motor is manufactured to proof the effectiveness by the measurement of the iron loss. Both results of the calculation and the measurement indicate that the iron loss of the proposed motor at the high rotational speed under the flux weakening control is reduced as half compared with the initial rotor shape while the torque is nearly constant.

  12. Development of a magnetic system for the treatment of Helicobacter pylori infections

    NASA Astrophysics Data System (ADS)

    Silva, Érica L.; Carvalho, Juliana F.; Pontes, Thales R. F.; Oliveira, Elquio E.; Francelino, Bárbara L.; Medeiros, Aldo C.; do Egito, E. Sócrates T.; Araujo, José H.; Carriço, Artur S.

    2009-05-01

    We report a study to develop a magnetic system for local delivery of amoxicillin. Magnetite microparticles produced by coprecipitation were coated with a solution of amoxicillin and Eudragit ®S100 by spray drying. Scanning electron microscopy, optical microscopy, X-ray powder diffraction and vibrating sample magnetometry revealed that the particles were superparamagnetic, with an average diameter of 17.2 μm, and an initial susceptibility controllable by the magnetite content in the suspension feeding the sprayer. Our results suggest a possible way to treat Helicobacter pylori infections, using an oral drug delivery system, and open prospects to coat magnetic microparticles by spray drying for biomedical applications.

  13. Development of a Two-Dimensional Micro-SQUID Array for Investigation of Magnetization Spatial Distribution

    NASA Astrophysics Data System (ADS)

    Sakuma, Daisuke; Shinozaki, Tomoya; Nago, Yusuke; Ishiguro, Ryosuke; Kashiwaya, Satoshi; Nomura, Shintaro; Kono, Kimitoshi; Takayanagi, Hideaki

    2016-05-01

    We developed a two-dimensional array of superconducting quantum interference devices (SQUIDs) for investigation of fine spatial distribution of magnetization in superconducting Sr2RuO4. Micrometer-sized SQUIDs based on homogeneously formed Al/AlOx/Al tunnel-type Josephson junctions were fabricated using shadow evaporation technique. Unnecessary electrodes formed by the shadow evaporation were removed by inductively coupled plasma reactive ion etching, in order to realize a dense array of SQUIDs. We measured the magnetic modulation of the maximum Josephson current of each SQUID in the array and evaluated the interaction among the SQUIDs.

  14. Magnetic Suspension Being Developed for Future Lube-Free Turbomachinery Application

    NASA Technical Reports Server (NTRS)

    Provenza, Andrew J.

    2003-01-01

    The NASA Glenn Research Center, the U.S. Army, Texas A&M University, and other industrial partners are continuing to work together to develop magnetic suspension technology to withstand the harsh environmental conditions inside current and future turbomachinery. In fiscal year 2002, our third-generation radial magnetic bearing successfully controlled rotor motion while at 1000 F (540 C) and 20 000 rpm. The ability to command the rotor s position while spinning at this speed was also demonstrated. Future work is planned to include radial bearing tests to 1100 F (593 C) and 30 000 rpm. In fiscal year 2003, we plan to test a high-temperature thrust bearing.

  15. Development of very small-diameter, inductively coupled magnetized plasma device.

    PubMed

    Kuwahara, D; Mishio, A; Nakagawa, T; Shinohara, S

    2013-10-01

    In order to miniaturize a high-density, inductively coupled magnetized plasma or helicon plasma to be applied to, e.g., an industrial application and an electric propulsion field, small helicon device has been developed. The specifications of this device along with the experimental results are described. We have succeeded in generating high-density (~10(19) m(-3)) plasmas using quartz tubes with very small diameters of 10 and 20 mm, with a radio frequency power ~1200 and 700 W, respectively, in the presence of the magnetic field less than 1 kG. PMID:24182105

  16. First names and perceptions of physical attractiveness.

    PubMed

    Erwin, P G

    1993-11-01

    I examined the impact of first names on ratings of physical attractiveness as judged by British undergraduate subjects using male and female full-face pictures presented on photographic slides. The photographs were identified with attractive names, unattractive names, or without any name indicated. Subjects rated the stimulus figures for physical attractiveness. Names accounted for approximately 6% of the variance in subjects' ratings of physical attractiveness. This effect was highly significant for pictures of women (p < .001), but nonsignificant for pictures of men (p > .05). PMID:8301616

  17. Role Stratospheric Balloon Magnetic Surveys in Development of Analytical Global Models of the Geomagnetic Field

    NASA Astrophysics Data System (ADS)

    Brekhov, O. M.; Tsvetkov, Yu. P.; Ivanov, V. V.; Filippov, S. V.; Tsvetkova, N. M.

    2015-09-01

    The results of stratospheric balloon gradient geomagnetic surveys at an altitude of ‘-~3O km with the use of the long (6 km) measuring base oriented along the vertical line are considered. The purposes of these surveys are the study of the magnetic field formed by deep sources, and the estimation of errors in modern analytical models of the geomagnetic field. The independent method of determination of errors in global analytical models of the normal magnetic field of the Earth (MFE) is substantiated. The new technique of identification of magnetic anomalies from surveys on long routes is considered. The analysis of gradient magnetic surveys on board the balloon, revealed the previously unknown features of the geomagnetic field. Using the balloon data, the EMM/720 model of the geomagnetic field (http://www.ngdc.noaa.gov/geomag/EMM) is investigated, and it is shown that this model unsatisfactorily represents the anomalous MFE, at least, at an altitude of 30 km, in the area our surveys. The unsatisfactory quality of aeromagnetic (ground-based) data is also revealed by the method of wavelet analysis of the ground-based and balloon magnetic profiles. It is shown, that the ground-based profiles do not contain inhomogeneities more than 1 30 km in size, whereas the balloon profiles (1000 km in the strike extent) contain inhomogeneities up to 600 km in size an the location of the latte coincides with the location of the satellite magnetic anomaly. On the basis of balloon data is shown, it that low-altitude aeromagnetic surveys, due to fundamental reasons, incorrectly reproduce the magnetic field of deep sources. This prevents the reliable conversion of ground-based magnetic anomalies upward from the surface of the Earth. It is shown, that an adequate global model of magnetic anomalies in the circumterrestrial space, developed up to 720 spherical harmonics, must be constructed only in accordance with the data obtained at satellite and stratospheric altitudes. Such a model

  18. Development of transition-metal doped copper oxide and zinc oxide dilute magnetic semiconductors

    NASA Astrophysics Data System (ADS)

    Ivill, Mathew P.

    The field of spintronics has recently attracted much attention because of its potential to provide new functionalities and enhanced performance in conventional electronic devices. Oxide materials provide a convenient platform to study the spin-based functionality in host semiconducting material. Recent theoretical treatments predict that wide band-gap semiconductors, including ZnO, can exhibit high temperature ferromagnetic ordering when doped with transition metals. This work focused on the possibility of using wide band-gap oxide semiconductors as potential spintronic materials. The structure, magnetic, and electronic transport properties of transition-metal doped ZnO and Cu 2O were investigated. Mn and Co were used as transition metal dopants. Thin films of these materials were fabricated using pulsed laser deposition (PLD). The Mn solubility in Cu2O was found to be small and the precipitation of Mn-oxides was favored at high growth temperatures. Phase pure Mn-doped Cu2O samples were found to be non-magnetic. Samples were p-type with carrier concentrations on the order of 1014-10 16 cm-3. The effects of carrier concentration on the magnetic properties of Mn-doped ZnO were studied using Sn and P as electronic codopants. Sn acts as an n-type dopant providing extra electrons to the ZnO. P acts as a p-type dopant that supplies excess holes to compensate the native electron concentration in ZnO. The electron concentration was decreased using P, but the films remained n-type. An inverse correlation was found between the ferromagnetism and the electron concentration; the ferromagnetic coupling between Mn spins increased with decreasing electron concentration. The nature of ferromagnetism in Co-doped ZnO was also investigated. Ferromagnetism was found in films deposited at 400°C in vacuum, while films deposited in oxygen or at higher temperatures were non-magnetic. Films deposited under vacuum had rather high electron concentrations and were presumably doped with

  19. Development of bearings and a damper based on magnetically controllable fluids

    NASA Astrophysics Data System (ADS)

    Guldbakke, J. M.; Hesselbach, J.

    2006-09-01

    This paper presents two different kinds of magnetically controllable fluid bearings and a new magnetorheological fluid damper based upon open porous metallic foams. For the bearings, it will distinguish between a magnetohydrostatic bearing and a hydrostatic bearing with a magnetically controllable fluid. The magnetohydrostatic bearings get their load bearing capacity from the magnetohydrostatic pressure that is generated by the gradient of the magnetic field along a fluid surface. With such magnetohydrostatic bearings a specific load up to 1.6 N cm2 can be reached. To support heavier loads hydrostatic bearings with magnetically controllable fluids can be used. This bearing concept makes it possible to achieve a constant bearing gap even if the load of the bearing changes. For this purpose the fluids are used as a hydraulic medium. Due to the magnetically controlled rheological behaviour of the fluid the bearing gap remains constant. The great advantage of this closed loop system compared to that of common hydrostatic bearings using valves is the quicker response to payload changes. The reason for that is that the active element (i.e. the fluid) acts directly inside the bearing gap and not outside like in the case of valves. The foam damper developed uses the fluid to produce controllable damping forces. The open porous foam is directly placed in the active volume of the damper. By moving the foam piston the magnetically controllable fluid is pressed through the pores. The flow in the pores can be controlled by changing the fluid viscosity by applying a magnetic field. With this damper structure it is possible to reach higher damping forces whilst featuring a small design space.

  20. Development of modulating permanent magnet sextupole lens for focusing of pulsed cold neutrons

    NASA Astrophysics Data System (ADS)

    Yamada, Masako; Iwashita, Yoshihisa; Ichikawa, Masahiro; Sugimoto, Takanori; Tongu, Hiromu; Fujisawa, Hiroshi; Shimizu, Hirohiko M.; Ino, Takashi; Mishima, Kenji; Taketani, Kaoru; Yoshioka, Tamaki; Muto, Suguru; Morishima, Takahiro; Oku, Takayuki; Suzuki, Jun-ichi; Shinohara, Takenao; Sakai, Kenji; Sato, Hiromi; Hirota, Katsuya; Otake, Yoshie; Seki, Yoshichika; Kawasaki, Shinsuke; Komamiya, Sachio; Kamiya, Yoshio; Otono, Hidetoshi; Yamashita, Satoru; Geltenbort, Peter

    2009-09-01

    Modulating permanent magnet sextupole lens (PMSx) for focusing pulsed cold neutrons is under development. The synchronized modulation of its field gradient suppresses the chromatic aberration which arises from the Time Of Flight method. The strength of the magnetic field, the torque, and the rise of temperature during its operation are studied on a fabricated prototype. Experiments on focusing pulsed very cold neutrons (VCN) at ILL (Institute of Laue Langevin, France) were carried out and VCN with around λ=40 Å were focused by the PMSx at a focal length of about 0.5 m. The experimental results are presented in conjunction with the principle of the neutron focusing and the modulating method of the focal strength of permanent magnet lens with the double ring structure.

  1. Development of magnetic bearing system for a new third-generation blood pump.

    PubMed

    Lee, Jung Joo; Ahn, Chi Bum; Choi, Jaesoon; Park, Jun Woo; Song, Seung-Joon; Sun, Kyung

    2011-11-01

    A magnetic bearing system is a crucial component in a third-generation blood pump, particularly when we consider aspects such as system durability and blood compatibility. Many factors such as efficiency, occupying volume, hemodynamic stability in the flow path, mechanical stability, and stiffness need to be considered for the use of a magnetic bearing system in a third-generation blood pump, and a number of studies have been conducted to develop novel magnetic bearing design for better handling of these factors. In this study, we developed and evaluated a new magnetic bearing system having a motor for a new third-generation blood pump. This magnetic bearing system consists of a magnetic levitation compartment and a brushless direct current (BLDC) motor compartment. The active-control degree of freedom is one; this control is used for controlling the levitation in the axial direction. The levitation in the radial direction has a passive magnetic levitation structure. In order to improve the system efficiency, we separated the magnetic circuit for axial levitation by using a magnetic circuit for motor drive. Each magnetic circuit in the bearing system was designed to have a minimum gap by placing mechanical parts, such as the impeller blades, outside the circuit. A custom-designed noncontact gap sensor was used for minimizing the system volume. We fabricated an experimental prototype of the proposed magnetic bearing system and evaluated its performance by a control system using the Matlab xPC Target system. The noncontact gap sensor was an eddy current gap sensor with an outer diameter of 2.38 mm, thickness of 0.88 mm, and resolution of 5 µm. The BLDC motor compartment was designed to have an outer diameter of 20 mm, length of 28.75 mm, and power of 4.5 W. It exhibited a torque of 8.6 mNm at 5000 rpm. The entire bearing system, including the motor and the sensor, had an outer diameter of 22 mm and a length of 97 mm. The prototype exhibited sufficient levitation

  2. Permanent magnet Hall Thrusters development and applications on future brazilian space missions

    NASA Astrophysics Data System (ADS)

    Ferreira, Jose Leonardo; Martins, Alexandre A.; Miranda, Rodrigo; Schelling, Adriane; de Souza Alves, Lais; Gonçalves Costa, Ernesto; de Oliveira Coelho Junior, Helbert; Castelo Branco, Artur; de Oliveira Lopes, Felipe Nathan

    2015-10-01

    The Plasma Physics Laboratory (PPLUnB) has been developing a Permanent Magnet Hall Thruster (PHALL) for the Space Research Program for Universities (UNIESPAÇO), part of the Brazilian Space Activities Program (PNAE) since 2004. The PHALL project consists on a plasma source design, construction and characterization of the Hall type that will function as a plasma propulsion engine and characterized by several plasma diagnostics sensors. PHALL is based on a plasma source in which a Hall current is generated inside a cylindrical annular channel with an axial electric field produced by a ring anode and a radial magnetic field produced by permanent magnets. In this work it is shown a brief description of the plasma propulsion engine, its diagnostics instrumentation and possible applications of PHALL on orbit transfer maneuvering for future Brazilian geostationary satellite space missions.

  3. Development of a compact permanent magnet helicon plasma source for ion beam bioengineering

    SciTech Connect

    Kerdtongmee, P.; Srinoum, D.; Nisoa, M.

    2011-10-15

    A compact helicon plasma source was developed as a millimeter-sized ion source for ion beam bioengineering. By employing a stacked arrangement of annular-shaped permanent magnets, a uniform axial magnetic flux density up to 2.8 kG was obtained. A cost effective 118 MHz RF generator was built for adjusting forward output power from 0 to 40 W. The load impedance and matching network were then analyzed. A single loop antenna and circuit matching elements were placed on a compact printed circuit board for 50 {Omega} impedance matching. A plasma density up to 1.1 x 10{sup 12} cm{sup -3} in the 10 mm diameter tube under the magnetic flux density was achieved with 35 W applied RF power.

  4. Development of a compact permanent magnet helicon plasma source for ion beam bioengineering.

    PubMed

    Kerdtongmee, P; Srinoum, D; Nisoa, M

    2011-10-01

    A compact helicon plasma source was developed as a millimeter-sized ion source for ion beam bioengineering. By employing a stacked arrangement of annular-shaped permanent magnets, a uniform axial magnetic flux density up to 2.8 kG was obtained. A cost effective 118 MHz RF generator was built for adjusting forward output power from 0 to 40 W. The load impedance and matching network were then analyzed. A single loop antenna and circuit matching elements were placed on a compact printed circuit board for 50 Ω impedance matching. A plasma density up to 1.1 × 10(12) cm(-3) in the 10 mm diameter tube under the magnetic flux density was achieved with 35 W applied RF power. PMID:22047290

  5. Development of the magnetic force-induced dual vibration energy harvester using a unimorph cantilever

    NASA Astrophysics Data System (ADS)

    Umaba, M.; Nakamachi, E.; Morita, Y.

    2015-12-01

    In this study, a high frequency piezoelectric energy harvester converted from the human low vibrated motion energy was newly developed. This hybrid energy harvester consists of the unimorph piezoelectric cantilever, the pendulum and a pair of permanent magnets. One magnet was attached at the edge of cantilever, and the counterpart magnet at the edge of pendulum. The mechanical energy provided through the human walking motion, which is a typical ubiquitous existence of vibration, is converted to the electric energy via the piezoelectric unimorph cantilever vibration. At first, we studied the energy convert mechanism and analyze the performance of novel energy harvester, where the resonance free vibration of unimorph piezoelectric cantilever generated a high electric power. Next, we equipped the counterpart permanent magnet at the edge of pendulum, which vibrates with a very low frequency caused by the human walking. Then the counterpart magnet was set at the edge of unimorph piezoelectric cantilever, which vibrated with a high frequency. This low-to-high frequency convert "dual vibration system" can be characterized as an enhanced energy harvester. We examined and obtained average values of voltage and power in this system, as 8.31 mV and 0.33 μW. Those results show the possibility to apply for the energy harvester in the portable and implantable Bio-MEMS devices.

  6. Ontogenetic development of magnetic compass orientation in domestic chickens (Gallus gallus).

    PubMed

    Denzau, Susanne; Nießner, Christine; Rogers, Lesley J; Wiltschko, Wolfgang

    2013-08-15

    Domestic chickens (Gallus gallus) can be trained to search for a social stimulus in a specific magnetic direction, and cryptochrome 1a, found in the retina, has been proposed as a receptor molecule mediating magnetic directions. The present study combines immuno-histochemical and behavioural data to analyse the ontogenetic development of this ability. Newly hatched chicks already have a small amount of cryptochrome 1a in their violet cones; on day 5, the amount of cryptochrome 1a reached the same level as in adult chickens, suggesting that the physical basis for magnetoreception is present. In behavioural tests, however, young chicks 5 to 7 days old failed to show a preference of the training direction; on days 8, 9 and 12, they could be successfully trained to search along a specific magnetic axis. Trained and tested again 1 week later, the chicks that had not shown a directional preference on days 5 to 7 continued to search randomly, while the chicks tested from day 8 onward preferred the correct magnetic axis when tested 1 week later. The observation that the magnetic compass is not functional before day 8 suggests that certain maturation processes in the magnetosensitive system in the brain are not yet complete before that day. The reasons why chicks that have been trained before that day fail to learn the task later remain unclear. PMID:23661773

  7. Development of an x-ray diffraction camera used in magnetic fields up to 10 T

    SciTech Connect

    Mitsui, Yoshifuru; Takahashi, Kohki; Watanabe, Kazuo; Koyama, Keiichi

    2011-12-15

    A high-field x-ray diffraction (HF-XRD) camera was developed to observe structural changes of magnetic materials in magnetic fields up to 10 T. The instrument mainly consists of a Debye-Scherrer-type camera with a diameter of 80.1 mm, a 10-T cryocooled superconducting magnet with a 100-mm room-temperature bore, an x-ray source, a power supply, and a chiller for the x-ray source. An x-ray detector (image plate) in the HF-XRD camera can be taken out and inserted into the magnet without changing the sample position. The performance of the instrument was tested by measuring the HF-XRD for silicon and ferromagnetic MnBi powders. A change of x-ray diffraction pattern was observed due to the magnetic orientation of MnBi, showing that the instrument is useful for studying field-induced orientation processes and structural properties of field-controlled materials.

  8. Development of an x-ray diffraction camera used in magnetic fields up to 10 T.

    PubMed

    Mitsui, Yoshifuru; Koyama, Keiichi; Takahashi, Kohki; Watanabe, Kazuo

    2011-12-01

    A high-field x-ray diffraction (HF-XRD) camera was developed to observe structural changes of magnetic materials in magnetic fields up to 10 T. The instrument mainly consists of a Debye-Scherrer-type camera with a diameter of 80.1 mm, a 10-T cryocooled superconducting magnet with a 100-mm room-temperature bore, an x-ray source, a power supply, and a chiller for the x-ray source. An x-ray detector (image plate) in the HF-XRD camera can be taken out and inserted into the magnet without changing the sample position. The performance of the instrument was tested by measuring the HF-XRD for silicon and ferromagnetic MnBi powders. A change of x-ray diffraction pattern was observed due to the magnetic orientation of MnBi, showing that the instrument is useful for studying field-induced orientation processes and structural properties of field-controlled materials. PMID:22225246

  9. Development of a high magnetic field assisted pulsed laser deposition system

    NASA Astrophysics Data System (ADS)

    Zhang, Kejun; Dai, Jianming; Wu, Wenbin; Zhang, Peng; Zuo, Xuzhong; Zhou, Shu; Zhu, Xuebin; Sheng, Zhigao; Liang, Changhao; Sun, Yuping

    2015-09-01

    A high magnetic field assisted pulsed laser deposition (HMF-PLD) system has been developed to in situ grow thin films in a high magnetic field up to 10 T. In this system, a specially designed PLD cylindrical vacuum chamber is horizontally located in the bore configuration of a superconducting magnet with a bore diameter of 200 mm. To adjust the focused pulsed laser into the target in such a narrow PLD vacuum chamber, an ingeniously built-in laser leading-in chamber is employed, including a laser mirror with a reflection angle of 65° and a damage threshold up to 3.4 J/cm2. A laser alignment system consisting of a built-in video-unit leading-in chamber and a low-energy alignment laser is applied to monitor and align the pulsed laser propagation in the PLD vacuum chamber. We have grown La0.7Sr0.3MnO3 (LSMO) thin films on (LaAlO3)0.3(Sr2AlTaO6)0.7 (001) [LSAT (001)] substrates by HMF-PLD. The results show that the nanostructures of the LSMO films can be tuned from an epitaxially continuous film structure without field to a vertically aligned nanorod structure with an applied high magnetic field above 5 T, and the dimension size of the nanorods can be tuned by the strength of the magnetic field. The associated magnetic anisotropy is found to be highly dependent on the nanorod structures. We show how the HMF-PLD provides an effective route toward tuning the nanostructures and the physical properties of functional thin films, giving it an important role in development of nanodevices and their application.

  10. Development of a high magnetic field assisted pulsed laser deposition system.

    PubMed

    Zhang, Kejun; Dai, Jianming; Wu, Wenbin; Zhang, Peng; Zuo, Xuzhong; Zhou, Shu; Zhu, Xuebin; Sheng, Zhigao; Liang, Changhao; Sun, Yuping

    2015-09-01

    A high magnetic field assisted pulsed laser deposition (HMF-PLD) system has been developed to in situ grow thin films in a high magnetic field up to 10 T. In this system, a specially designed PLD cylindrical vacuum chamber is horizontally located in the bore configuration of a superconducting magnet with a bore diameter of 200 mm. To adjust the focused pulsed laser into the target in such a narrow PLD vacuum chamber, an ingeniously built-in laser leading-in chamber is employed, including a laser mirror with a reflection angle of 65° and a damage threshold up to 3.4 J/cm(2). A laser alignment system consisting of a built-in video-unit leading-in chamber and a low-energy alignment laser is applied to monitor and align the pulsed laser propagation in the PLD vacuum chamber. We have grown La0.7Sr0.3MnO3 (LSMO) thin films on (LaAlO3)0.3(Sr2AlTaO6)0.7 (001) [LSAT (001)] substrates by HMF-PLD. The results show that the nanostructures of the LSMO films can be tuned from an epitaxially continuous film structure without field to a vertically aligned nanorod structure with an applied high magnetic field above 5 T, and the dimension size of the nanorods can be tuned by the strength of the magnetic field. The associated magnetic anisotropy is found to be highly dependent on the nanorod structures. We show how the HMF-PLD provides an effective route toward tuning the nanostructures and the physical properties of functional thin films, giving it an important role in development of nanodevices and their application. PMID:26429478

  11. Permanent Magnet Spiral Motor for Magnetic Gradient Energy Utilization: Axial Magnetic Field

    NASA Astrophysics Data System (ADS)

    Valone, Thomas F.

    2010-01-01

    The Spiral Magnetic Motor, which can accelerate a magnetized rotor through 90% of its cycle with only permanent magnets, was an energy milestone for the 20th century patents by Kure Tekkosho in the 1970's. However, the Japanese company used old ferrite magnets which are relatively weak and an electrically-powered coil to jump start every cycle, which defeated the primary benefit of the permanent magnet motor design. The principle of applying an inhomogeneous, anisotropic magnetic field gradient force Fz = μ cos φ dB/dz, with permanent magnets is well-known in physics, e.g., Stern-Gerlach experiment, which exploits the interaction of a magnetic moment with the aligned electron spins of magnetic domains. In this case, it is applied to dB/dθ in polar coordinates, where the force Fθ depends equally on the magnetic moment, the cosine of the angle between the magnetic moment and the field gradient. The radial magnetic field increases in strength (in the attractive mode) or decreases in strength (in the repulsive mode) as the rotor turns through one complete cycle. An electromagnetic pulsed switching has been historically used to help the rotor traverse the gap (detent) between the end of the magnetic stator arc and the beginning (Kure Tekko, 1980). However, alternative magnetic pulse and switching designs have been developed, as well as strategic eddy current creation. This work focuses on the switching mechanism, novel magnetic pulse methods and advantageous angular momentum improvements. For example, a collaborative effort has begun with Toshiyuki Ueno (University of Tokyo) who has invented an extremely low power, combination magnetostrictive-piezoelectric (MS-PZT) device for generating low frequency magnetic fields and consumes "zero power" for static magnetic field production (Ueno, 2004 and 2007a). Utilizing a pickup coil such as an ultra-miniature millihenry inductor with a piezoelectric actuator or simply Wiegand wire geometry, it is shown that the necessary

  12. A Two-Magnet System to Push Therapeutic Nanoparticles

    NASA Astrophysics Data System (ADS)

    Shapiro, Benjamin; Dormer, Kenneth; Rutel, Isaac B.

    2010-12-01

    Magnetic fields can be used to direct magnetically susceptible nanoparticles to disease locations: to infections, blood clots, or tumors. Any single magnet always attracts (pulls) ferro- or para-magnetic particles towards it. External magnets have been used to pull therapeutics into tumors near the skin in animals and human clinical trials. Implanting magnetic materials into patients (a feasible approach in some cases) has been envisioned as a means of reaching deeper targets. Yet there are a number of clinical needs, ranging from treatments of the inner ear, to antibiotic-resistant skin infections and cardiac arrhythmias, which would benefit from an ability to magnetically "inject", or push in, nanomedicines. We develop, analyze, and experimentally demonstrate a novel, simple, and effective arrangement of just two permanent magnets that can magnetically push particles. Such a system might treat diseases of the inner ear; diseases which intravenously injected or orally administered treatments cannot reach due to the blood-brain barrier.

  13. A Two-Magnet System to Push Therapeutic Nanoparticles

    PubMed Central

    Shapiro, Benjamin; Dormer, Kenneth; Rutel, Isaac B.

    2010-01-01

    Magnetic fields can be used to direct magnetically susceptible nanoparticles to disease locations: to infections, blood clots, or tumors. Any single magnet always attracts (pulls) ferro- or para-magnetic particles towards it. External magnets have been used to pull therapeutics into tumors near the skin in animals and human clinical trials. Implanting magnetic materials into patients (a feasible approach in some cases) has been envisioned as a means of reaching deeper targets. Yet there are a number of clinical needs, ranging from treatments of the inner ear, to antibiotic-resistant skin infections and cardiac arrhythmias, which would benefit from an ability to magnetically “inject”, or push in, nanomedicines. We develop, analyze, and experimentally demonstrate a novel, simple, and effective arrangement of just two permanent magnets that can magnetically push particles. Such a system might treat diseases of the inner ear; diseases which intravenously injected or orally administered treatments cannot reach due to the blood-brain barrier. PMID:21243119

  14. Development of Nuclear Magnetic Resonance Imaging/spectroscopy for improved petroleum recovery. Final report

    SciTech Connect

    Barrufet, M.A.; Flumerfelt, F.W.; Walsh, M.P.; Watson, A.T.

    1994-04-01

    The overall objectives of this program are to develop and apply Nuclear Magnetic Resonance Imaging (NMRI) and CT X-Ray Scanning methods for determining rock, fluid, and petrophysical properties and for fundamental studies of multiphase flow behavior in porous media. Specific objectives are divided into four subtasks: (1) development of NMRI and CT scanning for the determination of rock-fluid and petrophysical properties; (2) development of NMRI and CT scanning for characterizing conventional multiphase displacement processes; (3) development of NMR and CT scanning for characterizing dispersed phase processes; and (4) miscible displacement studies.

  15. Magnetic

    NASA Astrophysics Data System (ADS)

    Aboud, Essam; El-Masry, Nabil; Qaddah, Atef; Alqahtani, Faisal; Moufti, Mohammed R. H.

    2015-06-01

    The Rahat volcanic field represents one of the widely distributed Cenozoic volcanic fields across the western regions of the Arabian Peninsula. Its human significance stems from the fact that its northern fringes, where the historical eruption of 1256 A.D. took place, are very close to the holy city of Al-Madinah Al-Monawarah. In the present work, we analyzed aeromagnetic data from the northern part of Rahat volcanic field as well as carried out a ground gravity survey. A joint interpretation and inversion of gravity and magnetic data were used to estimate the thickness of the lava flows, delineate the subsurface structures of the study area, and estimate the depth to basement using various geophysical methods, such as Tilt Derivative, Euler Deconvolution and 2D modeling inversion. Results indicated that the thickness of the lava flows in the study area ranges between 100 m (above Sea Level) at the eastern and western boundaries of Rahat Volcanic field and getting deeper at the middle as 300-500 m. It also showed that, major structural trend is in the NW direction (Red Sea trend) with some minor trends in EW direction.

  16. Neural network controller development for a magnetically suspended flywheel energy storage system

    NASA Technical Reports Server (NTRS)

    Fittro, Roger L.; Pang, Da-Chen; Anand, Davinder K.

    1994-01-01

    A neural network controller has been developed to accommodate disturbances and nonlinearities and improve the robustness of a magnetically suspended flywheel energy storage system. The controller is trained using the back propagation-through-time technique incorporated with a time-averaging scheme. The resulting nonlinear neural network controller improves system performance by adapting flywheel stiffness and damping based on operating speed. In addition, a hybrid multi-layered neural network controller is developed off-line which is capable of improving system performance even further. All of the research presented in this paper was implemented via a magnetic bearing computer simulation. However, careful attention was paid to developing a practical methodology which will make future application to the actual bearing system fairly straightforward.

  17. Development of Magnetic Resonance-based Functional Imaging: The Past, the Present, and the Future.

    PubMed

    Matsumoto, Ken-Ichiro

    2016-01-01

    The term "theranostics" is a compound word combining "therapeutics" and "diagnostics". Discovery of the X-ray made an extraordinary contribution to the field of medical science. Development of computer science after World War II has been absolutely imperative for the development of medical imaging technology to date. The invention of X-ray computed tomography (CT) has revolutionized medical image diagnostic systems. Several functional imaging modalities emerged not only in the radiological field but also in magnetic resonance and ultrasonic fields. The fusion of three digital imaging techniques, MR Redox imaging, electron paramagnetic resonance (EPR) oxygen mapping, and hyperpolarized (13)C MRI techniques in the magnetic resonance field, contribute to the newly-termed theranostics. Future development of a suitable contrast agent for each imaging modality will be a key for the success of theranositics. PMID:27477720

  18. Special Coils Development at the National High Magnetic Field Laboratory in Toulouse

    NASA Astrophysics Data System (ADS)

    Béard, J.; Billette, J.; Frings, P.; Suleiman, M.; Lecouturier, F.

    2013-03-01

    The Laboratoire National des Champs Magnétiques Intenses (LNCMI) develops different types of coils suited to specific experiments. We present some recent developments on magnet design. Several coils are dedicated to experiments in large scale facilities in France and Switzerland. A 30 T split-pair coil for X-rays diffraction and one 40 T coil for plasma physics at the LULI, two 30 T coils with axial access (one with an conical bore) for X-ray diffraction and absorption experiments. A 40 T wide angle conical access solenoid with a high duty-cycle for neutron scattering at the ILL is being constructed. For use at the installation in Toulouse we have developed, apart from our standard 60 and 70 T coils, several special coils: a coil with a long optical path with 30 T transverse magnetic field and a 90 T long pulse dual coil system.

  19. New Magnetic Database Initiatives: Exploitation of and Integration with other Developments.

    NASA Astrophysics Data System (ADS)

    Constable, C.; Staudigel, H.; Tauxe, L.; Koppers, A.; Johnson, C.; Solheid, P.; Jackson, M.; Banerjee, S.; Pisarevsky, S.

    2002-12-01

    The steadily increasing collection of paleo, rock, and environmental magnetic data necessitates a community effort to ensure its timely electronic archival and allow appropriate exploitation of research tools from an IT perspective. This will ensure that scientific data gathered with public funds can be readily accessible to the broadest possible range of researchers. Although paleomagnetic databases providing a limited digital archive of legacy data have existed for some time, they lack the interoperability and generality required for the breadth of modern scientific endeavors. Drawing on expertise represented in both the Geochemical Earth Reference Model (GERM) and its parent body EarthRef.org protocols are being developed within the magnetics community that will provide the range of information needed for paleo and rock magnetic databases. The goal in establishing these databases is to provide an enduring digital archive that can be exploited for current scientific investigations, and permit new and interdisciplinary studies that can explore combinations of measurements not previously considered. While strategies for harvesting legacy data are also desirable, a strong focus on gathering newly collected data at the publication stage is necessary, so that these data become broadly available in a timely fashion. The ongoing dialog on minimal and desirable metadata suitable for magnetic databases has a strong basis in the traditional geophysical areas in which magnetic data are applied, and must also include fundamental rock magnetic information. The metadata must be designed to allow flexible syntheses of magnetic data into the standard kinds of models (such as magnetostratigraphic time scales, geomagnetic field models, plate reconstructions, etc.) and be sufficiently general to enable cross-fertilization with communities involved in related geophysical enterprises such as stratigraphy, petrology, radiometric dating, tectonics and paleoclimate studies. This

  20. Electron attraction mediated by Coulomb repulsion.

    PubMed

    Hamo, A; Benyamini, A; Shapir, I; Khivrich, I; Waissman, J; Kaasbjerg, K; Oreg, Y; von Oppen, F; Ilani, S

    2016-07-21

    One of the defining properties of electrons is their mutual Coulomb repulsion. However, in solids this basic property may change; for example, in superconductors, the coupling of electrons to lattice vibrations makes the electrons attract one another, leading to the formation of bound pairs. Fifty years ago it was proposed that electrons can be made attractive even when all of the degrees of freedom in the solid are electronic, by exploiting their repulsion from other electrons. This attraction mechanism, termed 'excitonic', promised to achieve stronger and more exotic superconductivity. Yet, despite an extensive search, experimental evidence for excitonic attraction has yet to be found. Here we demonstrate this attraction by constructing, from the bottom up, the fundamental building block of the excitonic mechanism. Our experiments are based on quantum devices made from pristine carbon nanotubes, combined with cryogenic precision manipulation. Using this platform, we demonstrate that two electrons can be made to attract each other using an independent electronic system as the 'glue' that mediates attraction. Owing to its tunability, our system offers insights into the underlying physics, such as the dependence of the emergent attraction on the underlying repulsion, and the origin of the pairing energy. We also demonstrate transport signatures of excitonic pairing. This experimental demonstration of excitonic pairing paves the way for the design of exotic states of matter. PMID:27443742

  1. Sexual Attractiveness of Males and Females.

    ERIC Educational Resources Information Center

    Taylor, Peggy; And Others

    The most important characteristics for females judging the attractiveness of males, and for males judging females, were eyes, body build and facial complexion. Previously, females tended to place less importance on physical components of attraction for both themselves and men. Possible interpretations are: (1) women have become more egalitarian…

  2. Interpersonal Attraction in the Counseling Relationship.

    ERIC Educational Resources Information Center

    Wachowiak, Dale; Diaz, Sandra

    Murstein's Stimulus-Value-Role theory of dyadic relationships, in which attraction depends on the exchange value of the assets and liabilities each person brings to the situation, is employed as a foundation for this review of the literature on interpersonal attraction in the counseling relationship. A three-stage model, accounting for both…

  3. An innovative mosquito trap for testing attractants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We describe a simple trap modification for testing or using attractants to collect flying mosquitoes. The trap also can test the effectiveness of spatial repellents. The proposed design may facilitate standardized testing of mosquito attractants and repellents. The trap uses a standard Centers f...

  4. An Attributional Approach to Counselor Attractiveness.

    ERIC Educational Resources Information Center

    Hackman, Hollis W.; Claiborn, Charles D.

    1982-01-01

    Examined two components of counselor attractiveness--perceived similarity and liking--in a comparison of two theoretical approaches to attractiveness and influence in counseling--the referent power hypothesis and an attributional approach. Results generally support the attributional approach over the reference power hypothesis. (Author)

  5. Correlates of Attraction Among Preschool Children.

    ERIC Educational Resources Information Center

    Ross, Michael B.

    The generalizability of several variables which have been related to attraction among adults to preschool children was investigated. It was found that perceived physical attractiveness, perceived proximity, and familiarity are all significantly positively correlated with how popular a child is in his nursery school class. (Author)

  6. Brain Systems for Assessing Facial Attractiveness

    ERIC Educational Resources Information Center

    Winston, Joel S.; O'Doherty, John; Kilner, James M.; Perrett, David I.; Dolan, Raymond J.

    2007-01-01

    Attractiveness is a facial attribute that shapes human affiliative behaviours. In a previous study we reported a linear response to facial attractiveness in orbitofrontal cortex (OFC), a region involved in reward processing. There are strong theoretical grounds for the hypothesis that coding stimulus reward value also involves the amygdala. The…

  7. Electron attraction mediated by Coulomb repulsion

    NASA Astrophysics Data System (ADS)

    Hamo, A.; Benyamini, A.; Shapir, I.; Khivrich, I.; Waissman, J.; Kaasbjerg, K.; Oreg, Y.; von Oppen, F.; Ilani, S.

    2016-07-01

    One of the defining properties of electrons is their mutual Coulomb repulsion. However, in solids this basic property may change; for example, in superconductors, the coupling of electrons to lattice vibrations makes the electrons attract one another, leading to the formation of bound pairs. Fifty years ago it was proposed that electrons can be made attractive even when all of the degrees of freedom in the solid are electronic, by exploiting their repulsion from other electrons. This attraction mechanism, termed ‘excitonic’, promised to achieve stronger and more exotic superconductivity. Yet, despite an extensive search, experimental evidence for excitonic attraction has yet to be found. Here we demonstrate this attraction by constructing, from the bottom up, the fundamental building block of the excitonic mechanism. Our experiments are based on quantum devices made from pristine carbon nanotubes, combined with cryogenic precision manipulation. Using this platform, we demonstrate that two electrons can be made to attract each other using an independent electronic system as the ‘glue’ that mediates attraction. Owing to its tunability, our system offers insights into the underlying physics, such as the dependence of the emergent attraction on the underlying repulsion, and the origin of the pairing energy. We also demonstrate transport signatures of excitonic pairing. This experimental demonstration of excitonic pairing paves the way for the design of exotic states of matter.

  8. Attitude Similarity, Topic Importance, and Psychotherapeutic Attraction

    ERIC Educational Resources Information Center

    Cheney, Thomas

    1975-01-01

    The effect of attitude similarity and topic importance on attraction was studied by exposing 75 prison inmates, incarcerated for public intoxication, to varying attitudes of a psychotherapist. Subjects were more attracted to the therapist after receiving alcohol items regardless of degree of similarity expressed. (Author)

  9. Attraction, Discrepancy and Responses to Psychological Treatment.

    ERIC Educational Resources Information Center

    Patton, Michael J.

    The responses of a laboratory subject (S) to a counselor-accomplice and to the psychological treatment situation are examined by manipulating experimentally interpersonal attraction and communication discrepancy. Four treatment conditions were set up: (1) topic similarity and positive attraction for counselor, (2) topic discrepancy and positive…

  10. Liquid Marbles Based on Magnetic Upconversion Nanoparticles as Magnetically and Optically Responsive Miniature Reactors for Photocatalysis and Photodynamic Therapy.

    PubMed

    Wang, Dan; Zhu, Lin; Chen, Jian-Feng; Dai, Liming

    2016-08-26

    Magnetic liquid marbles have recently attracted extensive attention for various potential applications. However, conventional liquid marbles based on iron oxide nanoparticles are opaque and inadequate for photo-related applications. Herein, we report the first development of liquid marbles coated with magnetic lanthanide-doped upconversion nanoparticles (UCNPs) that can convert near-infrared light into visible light. Apart from their excellent magnetic and mechanical properties, which are attractive for repeatable tip opening and magnetically directed movements, the resultant UCNP-based liquid marbles can act as ideal miniature reactors for photodynamic therapy of cancer cells. This work opens new ways for the development of liquid marbles, and shows great promise for liquid marbles based on UCNPs to be used in a large variety of potential applications, such as photodynamic therapy for accelerated drug screening, magnetically guided controlled drug delivery and release, and multifunctional actuation. PMID:27487265

  11. Development of magnetic resonance imaging based detection methods for beta amyloids via sialic acid-functionalized magnetic nanoparticles

    NASA Astrophysics Data System (ADS)

    Kouyoumdjian, Hovig

    The development of a non-invasive method for the detection of Alzheimer's disease is of high current interest, which can be critical in early diagnosis and in guiding preventive treatment of the disease. The aggregates of beta amyloids are a pathological hallmark of Alzheimer's disease. Carbohydrates such as sialic acid terminated gangliosides have been shown to play significant roles in initiation of amyloid aggregation. Herein, we report a biomimetic approach using sialic acid coated iron oxide superparamagnetic nanoparticles for in vitro detection in addition to the assessment of the in vivo mouse-BBB (Blood brain barrier) crossing of the BSA (bovine serum albumin)-modified ones. The sialic acid functionalized dextran nanoparticles were shown to bind with beta amyloids through several techniques including ELISA (enzyme linked immunosorbent assay), MRI (magnetic resonance imaging), TEM (transmission electron microscopy), gel electrophoresis and tyrosine fluorescence assay. The superparamagnetic nature of the nanoparticles allowed easy detection of the beta amyloids in mouse brains in both in vitro and ex vivo model by magnetic resonance imaging. Furthermore, the sialic acid nanoparticles greatly reduced beta amyloid induced cytotoxicity to SH-SY5Y neuroblastoma cells, highlighting the potential of the glyconanoparticles for detection and imaging of beta amyloids. Sialic acid functionalized BSA (bovine serum albumin) nanoparticles also showed significant binding to beta amyloids, through ELISA and ex vivo mouse brain MRI experiments. Alternatively, the BBB crossing was demonstrated by several techniques such as confocal microscopy, endocytosis, exocytosis assays and were affirmed by nanoparticles transcytosis assays through bEnd.3 endothelial cells. Finally, the BBB crossing was confirmed by analyzing the MRI signal of nanoparticle-injected CD-1 mice.

  12. Attracting Lagrangian coherent structures on Riemannian manifolds.

    PubMed

    Karrasch, Daniel

    2015-08-01

    It is a wide-spread convention to identify repelling Lagrangian Coherent Structures (LCSs) with ridges of the forward finite-time Lyapunov exponent (FTLE) field and to identify attracting LCSs with ridges of the backward FTLE. However, we show that, in two-dimensional incompressible flows, also attracting LCSs appear as ridges of the forward FTLE field. This raises the issue of the characterization of attracting LCSs using a forward finite-time Lyapunov analysis. To this end, we extend recent results regarding the relationship between forward and backward maximal and minimal FTLEs, to both the whole finite-time Lyapunov spectrum and to stretch directions. This is accomplished by considering the singular value decomposition (SVD) of the linearized flow map. By virtue of geometrical insights from the SVD, we provide characterizations of attracting LCSs in forward time for two geometric approaches to hyperbolic LCSs. We apply these results to the attracting FTLE ridge of the incompressible saddle flow. PMID:26328582

  13. Attracting Lagrangian coherent structures on Riemannian manifolds

    NASA Astrophysics Data System (ADS)

    Karrasch, Daniel

    2015-08-01

    It is a wide-spread convention to identify repelling Lagrangian Coherent Structures (LCSs) with ridges of the forward finite-time Lyapunov exponent (FTLE) field and to identify attracting LCSs with ridges of the backward FTLE. However, we show that, in two-dimensional incompressible flows, also attracting LCSs appear as ridges of the forward FTLE field. This raises the issue of the characterization of attracting LCSs using a forward finite-time Lyapunov analysis. To this end, we extend recent results regarding the relationship between forward and backward maximal and minimal FTLEs, to both the whole finite-time Lyapunov spectrum and to stretch directions. This is accomplished by considering the singular value decomposition (SVD) of the linearized flow map. By virtue of geometrical insights from the SVD, we provide characterizations of attracting LCSs in forward time for two geometric approaches to hyperbolic LCSs. We apply these results to the attracting FTLE ridge of the incompressible saddle flow.

  14. How facial attractiveness affects sustained attention.

    PubMed

    Li, Jie; Oksama, Lauri; Hyönä, Jukka

    2016-10-01

    The present study investigated whether and how facial attractiveness affects sustained attention. We adopted a multiple-identity tracking paradigm, using attractive and unattractive faces as stimuli. Participants were required to track moving target faces amid distractor faces and report the final location of each target. In Experiment 1, the attractive and unattractive faces differed in both the low-level properties (i.e., luminance, contrast, and color saturation) and high-level properties (i.e., physical beauty and age). The results showed that the attractiveness of both the target and distractor faces affected the tracking performance: The attractive target faces were tracked better than the unattractive target faces; when the targets and distractors were both unattractive male faces, the tracking performance was poorer than when they were of different attractiveness. In Experiment 2, the low-level properties of the facial images were equalized. The results showed that the attractive target faces were still tracked better than unattractive targets while the effects related to distractor attractiveness ceased to exist. Taken together, the results indicate that during attentional tracking the high-level properties related to the attractiveness of the target faces can be automatically processed, and then they can facilitate the sustained attention on the attractive targets, either with or without the supplement of low-level properties. On the other hand, only low-level properties of the distractor faces can be processed. When the distractors share similar low-level properties with the targets, they can be grouped together, so that it would be more difficult to sustain attention on the individual targets. PMID:27347672

  15. Development of materials related to the 60T and 100T magnets

    SciTech Connect

    Han, K.; Embury, J.D.

    1997-12-31

    In the past year, the effort in materials science related to the 60T and 100T magnets at Los Alamos has been concentrated in three areas: (a) development of a fabrication route for Cu-Ag wire in collaboration with Handy and Harman and IGC and (b) investigation of the mechanical properties of a variety of potential high strength high conductivity materials (c) selection of the reinforcement materials for the coils and development of a fabrication route for these materials. The selection of the conductors and reinforcement materials is based on their mechanical properties and electrical properties at cryogenic temperature ({minus} 196 C). The authors have taken the approach of trying to relate the properties both to design requirements and to the service life of magnet. Thus, they have given some consideration both to the role of the internal stresses developed during the fabrication on the elastic-plastic transition and on the mechanical and thermal stability of heavily drawn wires. The feasibility of the fabrication route and the cost of manufacturing the materials must also be considered. They have emphasized the need to develop a fabrication route capable of producing the conductors with homogeneous mechanical and electrical properties and with a cross-section of 8.6 mm x 5.2 mm and 146 m in length or longer for a 100T magnet.

  16. Development of the 1.2 T~1.5 T Permanent Magnetic Resonance Imaging Device and Its Application for Mouse Imaging

    PubMed Central

    Wang, Guangxin; Xie, Huantong; Hou, Shulian; Chen, Wei; Zhao, Qiang; Li, Shiyu

    2015-01-01

    By improving the main magnet, gradient, and RF coils design technology, manufacturing methods, and inventing new magnetic resonance imaging (MRI) special alloy, a cost-effective and small animal specific permanent magnet-type three-dimensional magnetic resonance imager was developed. The main magnetic field strength of magnetic resonance imager with independent intellectual property rights is 1.2~1.5 T. To demonstrate its effectiveness and validate the mouse imaging experiments in different directions, we compared the images obtained by small animal specific permanent magnet-type three-dimensional magnetic resonance imager with that obtained by using superconductor magnetic resonance imager for clinical diagnosis. PMID:26539531

  17. Effects of Strong Static Magnetic Fields on Amphibian Development and Gene Expression

    NASA Astrophysics Data System (ADS)

    Kawakami, Satomi; Kashiwagi, Keiko; Furuno, Nobuaki; Yamashita, Masamichi; Kashiwagi, Akihiko; Tanimoto, Yoshifumi

    2006-07-01

    This investigation attempts to clarify the effects of strong vertical and static magnetic fields (SMFs) of 11-15 T on Xenopus laevis development and on Xotx2 (an important regulator of fore- and midbrain morphogenesis) and Xag1 (essential for cement gland formation) gene expression. Results showed that (1) a strong SMF significantly retarded normal development and induced microcephaly, two heads, abnormal cement glands and multiple malformations, indicating that SMF inhibits normal embryonic development, (2) a strong SMF suppressed Xotx2 and Xag1 expression.

  18. The Development of a Ceramic Mold for Hot-Forging of Micro-Magnets

    SciTech Connect

    Christenson, Todd; Garino, Terry

    1999-06-25

    A new mold material has been developed for use in making rare-earth permanent magnet components with precise dimensions in the 10 to 1000 µm range by hot-forging. These molds are made from molds poly(methyl)methacrylate (PMMA) made by deep x-ray lithography (DXRL). An alumina bonded with colloidal silica has been developed for use in these molds. This material can be heated to 950°C without changing dimensions where it develops the strength needed to withstand the hot-fmging conditions (750°C, 100 MPa). In addition, it disintegrates in HF so that parts can be easily removed after forging.

  19. Development of a Proof of Concept Low Temperature Superfluid Magnetic Pump with Applications

    NASA Astrophysics Data System (ADS)

    Jahromi, Amir E.

    State of the art particle and photon detectors such as Transition Edge Sensors (TES) and Microwave Kinetic Inductance Detectors (MKID) use large arrays of sensors or detectors for space science missions. As the size of these space science detectors increases, future astrophysics missions will require sub-Kelvin coolers over larger areas. This leads to not only increased cooling power requirements, but also a requirement for distributed sub-Kelvin cooling. Development of a proof of concept Superfluid Magnetic Pump is discussed in this work. This novel low temperature, no moving part pump can replace the existing bellows-piston driven 4He or 3He- 4He mixture compressor/circulators used in various sub Kelvin refrigeration systems such as dilution, Superfluid pulse tube, or active magnetic regenerative refrigerators. Due to its superior thermal transport properties this pump can also be used as a simple circulator of sub-Lambda 4He to distribute cooling over large surface areas. The pump discussed in this work was experimentally shown to produce a maximum flow rate of 440 mg/s (averaged over cycle), 665 mg/s (peak) and produced a maximum pressure difference of 2323 Pascal. This pump worked in an "ideal" thermodynamic state: The experimental results matched with the theoretical values predicted by a computer model. Pump curves were developed to map the performance of this pump. This successful demonstration will enable this novel pump to be put to test in suitable sub Kelvin refrigeration systems. Numerical modeling of an Active Magnetic Regenerative Refrigerator (AMRR) that uses the Superfluid Magnetic Pump (SMP) to circulate liquid 3He-4He through a magnetic regenerator is presented as a potential application of such a pump.

  20. Development of Active Regions: Flows, Magnetic-Field Patterns and Bordering Effect

    NASA Astrophysics Data System (ADS)

    Getling, A. V.; Ishikawa, R.; Buchnev, A. A.

    2016-02-01

    A qualitative analysis is given of the data on the full magnetic and velocity vector fields in a growing sunspot group, recorded nearly simultaneously with the Solar Optical Telescope on the Hinode satellite. Observations of a young bipolar subregion developing within AR 11313 were carried out on 9 - 10 October 2011. Our aim was to form an idea about the consistency of the observed pattern with the well-known rising-tube model of the formation of bipolar active regions and sunspot groups. We find from our magnetograms that the distributions of the vertical [Bv] and the horizontal [Bh] component of the magnetic field over the area of the magnetic subregion are spatially well correlated; in contrast, the rise of a flux-tube loop would result in a qualitatively different pattern, with the maxima of the two magnetic-field components spatially separated: the vertical field would be the strongest where either spot emerges, while the maximum horizontal-field strengths would be reached in between them. A specific feature, which we call the bordering effect, is revealed: some local extrema of Bv are bordered with areas of locally enhanced Bh. This effect suggests a fountainlike spatial structure of the magnetic field near the Bv extrema, which is also hardly compatible with the emergence of a flux-tube loop. The vertical-velocity field in the area of the developing active subregion does not exhibit any upflow on the scale of the whole subregion, which should be related to the rising-tube process. Thus, our observational data can hardly be interpreted in the framework of the rising-tube model.

  1. Attraction by Repulsion: Pairing Electrons using Electrons

    NASA Astrophysics Data System (ADS)

    Ilani, Shahal

    One of the fundamental properties of electrons is their mutual Columbic repulsion. If electrons are placed in a solid, however, this basic property may change. A famous example is that of superconductors, where coupling to lattice vibrations makes electrons attractive and leads to the formation of bound pairs. But what if all the degrees of freedom in the solid are electronic? Is it possible to make electrons attract each other only by their repulsion to other electrons? Such an `excitonic' mechanism for attraction was proposed fifty years ago by W. A. Little, with the hope that it could lead to better and more exotic superconductivity. Yet, despite many efforts to synthesize materials that possess this unique property, to date there is still no evidence for electronic-based attraction. In this talk I will present our recent experiments that observe this unusual electronic attraction using a different, bottom-up approach. Our experiments are based on a new generation of quantum devices made from pristine carbon nanotubes, combined with precision cryogenic manipulation. Using this setup we can now assemble the fundamental building block of the excitonic attraction and demonstrate that two electrons that naturally repel each other can be made attractive using an independent electronic system as the binding glue. I will discuss the lessons learned from these experiments on what is achievable with plain electrostatics, and on the possibility to use the observed mechanism for creating exotic states of matter.

  2. Development of Magnetization Measurement Devices Using Micro-dc-SQUIDs and a Sr_2RuO_4 Microplate

    NASA Astrophysics Data System (ADS)

    Nago, Y.; Shinozaki, T.; Tsuchiya, S.; Ishiguro, R.; Kashiwaya, H.; Kashiwaya, S.; Nomura, S.; Kono, K.; Takayanagi, H.; Maeno, Y.

    2016-05-01

    We developed high-sensitivity magnetization measurement devices composed of micro-dc-SQUIDs and a superconducting Sr_2RuO_4 microplate, aiming to investigate novel magnetic properties related to a spin-triplet chiral p-wave superconductor with a mesoscopic size. Micron-sized dc-SQUID was fabricated by thin Al electrodes, and the SQUID structure was improved to prevent magnetic fluxes from intruding into SQUID electrodes. A Sr_2RuO_4 superconducting microplate was fabricated into the size as small as the SQUID loop using a focused ion beam and directly mounted on the SQUID with precise positioning for high-sensitivity magnetization measurements. In the preliminary magnetization measurements of this device, we observed vortices trapped into the plate and thus the lower critical field. The improved magnetization measurement device developed to exclude undesirable flux intrusion successfully enabled high-sensitivity detection of quantized vortex.

  3. How microorganisms avoid phagocyte attraction.

    PubMed

    Bestebroer, Jovanka; De Haas, Carla J C; Van Strijp, Jos A G

    2010-05-01

    Microorganisms have developed several mechanisms to modulate the host immune system to increase their survival and propagation in the host. Their presence in the host is not only revealed by self-produced peptides but also through host-derived chemokines and active complement fragments. These so-called chemoattractants are recognized by G protein-coupled receptors (GPCRs) expressed on leukocyte cell membranes. Activation of GPCRs triggers leukocyte activation and guides their recruitment to the site of infection. Therefore, GPCRs play a central role in leukocyte trafficking leading to microbial clearance. It is therefore not surprising that microorganisms are able to sabotage this arm of the immune response. Different microorganisms have evolved a variety of tactics to modulate GPCR activation. Here, we review the mechanisms and proteins used by major human pathogens and less virulent microorganisms that affect GPCR signaling. While viruses generally produce receptor and chemoattractant mimics, parasites and bacteria such as Staphylococcus aureus, Streptococcus pyogenes, Porphyromonas gingivalis, and Bordetella pertussis secrete proteins that affect receptor signaling, directly antagonize receptors, cleave stimuli, and even prevent stimulus generation. As the large arsenal of GPCR modulators aids prolonged microbial persistence in the host, their study provides us a better understanding of microbial pathogenesis. PMID:20059549

  4. The Putative Son's Attractiveness Alters the Perceived Attractiveness of the Putative Father.

    PubMed

    Prokop, Pavol

    2015-08-01

    A body of literature has investigated female mate choice in the pre-mating context (pre-mating sexual selection). Humans, however, are long-living mammals forming pair-bonds which sequentially produce offspring. Post-mating evaluations of a partner's attractiveness may thus significantly influence the reproductive success of men and women. I tested herein the theory that the attractiveness of putative sons provides extra information about the genetic quality of fathers, thereby influencing fathers' attractiveness across three studies. As predicted, facially attractive boys were more frequently attributed to attractive putative fathers and vice versa (Study 1). Furthermore, priming with an attractive putative son increased the attractiveness of the putative father with the reverse being true for unattractive putative sons. When putative fathers were presented as stepfathers, the effect of the boy's attractiveness on the stepfather's attractiveness was lower and less consistent (Study 2). This suggests that the presence of an attractive boy has the strongest effect on the perceived attractiveness of putative fathers rather than on non-fathers. The generalized effect of priming with beautiful non-human objects also exists, but its effect is much weaker compared with the effects of putative biological sons (Study 3). Overall, this study highlighted the importance of post-mating sexual selection in humans and suggests that the heritable attractive traits of men are also evaluated by females after mating and/or may be used by females in mate poaching. PMID:25731909

  5. Attitudes and attraction: a new test of the attraction, repulsion and similarity-dissimilarity asymmetry hypotheses.

    PubMed

    Singh, R; Ho, S Y

    2000-06-01

    Dissimilarity and similarity between attitudes of the participants and a stranger were manipulated across two sets of issues to test the attraction, repulsion and similarity-dissimilarity asymmetry hypotheses. Participants (N = 192) judged social (liking, enjoyment of company) and intellectual (intelligence, general knowledge) attractiveness of the stranger. The similarity in the first set of attitudes x similarity in the second set of attitudes effect emerged in social attraction, but not in intellectual attraction. Stated simply, dissimilarity had a greater weight than similarity in social attraction, but equal weight in intellectual attraction. These results support the similarity-dissimilarity asymmetry hypothesis that predicts dissimilarity-repulsion to be stronger than similarity-attraction. However, they reject (1) the attraction hypothesis that dissimilarity and similarity produce equal and opposite effects on social attraction; and (2) the repulsion hypothesis that only dissimilar attitudes affect social attraction by leading to repulsion. An equal weighting of dissimilarity and similarity in intellectual attraction further suggested that the similarity-dissimilarity asymmetry on social attraction is reflective of a stronger avoidance response in the Darwinian sense. PMID:10907095

  6. Current status and recent topics of rare-earth permanent magnets

    NASA Astrophysics Data System (ADS)

    Sugimoto, S.

    2011-02-01

    After the development of Nd-Fe-B magnets, rare-earth magnets are now essential components in many fields of technology, because of their ability to provide a strong magnetic flux. There are two, well-established techniques for the manufacture of rare earth magnets: powder metallurgy is used to obtain high-performance, anisotropic, fully dense magnet bodies; and the melt-spinning or HDDR (hydrogenation, disproportionation, desorption and recombination) process is widely used to produce magnet powders for bonded magnets. In the industry of sintered Nd-Fe-B magnets, the total amount of production has increased and their dominant application has been changed to motors. In particular, their use for motors in hybrid cars is one of the most attractive applications. Bonded magnets have also been used for small motors, and the studies of nanocomposite and Sm-Fe-N magnets have become widespread. This paper reviews the current status and future trend in the research of permanent magnets.

  7. Further technical development in magnetic resonance imaging of the brain in children.

    PubMed

    Young, I R; Dubowitz, L M; Pennock, J M; Bydder, G M

    1988-11-01

    Further technical developments implemented in magnetic resonance imaging (MRI) of the brain in children are described. These include the use of longer data collection periods, T2-dependent field echoes, susceptibility mapping, short inversion time inversion recovery sequences, very long echo time spin-echo sequences, and phase mapping techniques to detect tissue perfusion. These techniques are illustrated in selected cases and have increased the range of options available in MR examinations of children. PMID:3243057

  8. Development of a Magnetic Beads Quantitative Detection System for Fast Diagnosis

    NASA Astrophysics Data System (ADS)

    Yamamoto, Yujiro; Morishita, Tomohiro; Matsuyama, Kenji; Takasa, Kenji; Shibasaki, Ichiro

    This paper reports the development and performance of a detection system for magnetic beads. The system consists of a semiconductor based magneto-resistance sensor for beads detection and a lateral flow kit. Detection of anti-gen of H.Influenza at concentration of 0.1ng/ml was performed with satisfactory sensitivity, showing the system to be a promising for immunoassay.

  9. Development of low temperature and high magnetic field X-ray diffraction facility

    NASA Astrophysics Data System (ADS)

    Shahee, Aga; Sharma, Shivani; Singh, K.; Lalla, N. P.; Chaddah, P.

    2015-06-01

    The current progress of materials science regarding multifunctional materials (MFM) has put forward the challenges to understand the microscopic origin of their properties. Most of such MFMs have magneto-elastic correlations. To investigate the underlying mechanism it is therefore essential to investigate the structural properties in the presence of magnetic field. Keeping this in view low temperature and high magnetic field (LTHM) powder x-ray diffraction (XRD), a unique state-of-art facility in the country has been developed at CSR Indore. This setup works on symmetric Bragg Brentano geometry using a parallel incident x-ray beam from a rotating anode source working at 17 kW. Using this one can do structural studies at non-ambient conditions i.e. at low- temperatures (2-300 K) and high magnetic field (+8 to -8 T). The available scattering angle ranges from 5° to 115° 2θ with a resolution better than 0.1°. The proper functioning of the setup has been checked using Si sample. The effect of magnetic field on the structural properties has been demonstrated on Pr0.5Sr0.5MnO3 sample. Clear effect of field induced phase transition has been observed. Moreover, the effect of zero field cooled and field cooled conditions is also observed.

  10. Development of low temperature and high magnetic field X-ray diffraction facility

    SciTech Connect

    Shahee, Aga; Sharma, Shivani; Singh, K.; Lalla, N. P. Chaddah, P.

    2015-06-24

    The current progress of materials science regarding multifunctional materials (MFM) has put forward the challenges to understand the microscopic origin of their properties. Most of such MFMs have magneto-elastic correlations. To investigate the underlying mechanism it is therefore essential to investigate the structural properties in the presence of magnetic field. Keeping this in view low temperature and high magnetic field (LTHM) powder x-ray diffraction (XRD), a unique state-of-art facility in the country has been developed at CSR Indore. This setup works on symmetric Bragg Brentano geometry using a parallel incident x-ray beam from a rotating anode source working at 17 kW. Using this one can do structural studies at non-ambient conditions i.e. at low- temperatures (2-300 K) and high magnetic field (+8 to −8 T). The available scattering angle ranges from 5° to 115° 2θ with a resolution better than 0.1°. The proper functioning of the setup has been checked using Si sample. The effect of magnetic field on the structural properties has been demonstrated on Pr{sub 0.5}Sr{sub 0.5}MnO{sub 3} sample. Clear effect of field induced phase transition has been observed. Moreover, the effect of zero field cooled and field cooled conditions is also observed.

  11. Magic-Angle-Spinning NMR Magnet Development: Field Analysis and Prototypes

    PubMed Central

    Voccio, John; Hahn, Seungyong; Park, Dong Keun; Ling, Jiayin; Kim, Youngjae; Bascuñán, Juan; Iwasa, Yukikazu

    2013-01-01

    We are currently working on a program to complete a 1.5 T/75 mm RT bore magic-angle-spinning nuclear magnetic resonance magnet. The magic-angle-spinning magnet comprises a z-axis 0.866-T solenoid and an x-axis 1.225-T dipole, each to be wound with NbTi wire and operated at 4.2 K in persistent mode. A combination of the fields creates a 1.5-T field pointed at 54.74 degrees (magic angle) from the rotation (z) axis. In the first year of this 3-year program, we have completed magnetic analysis and design of both coils. Also, using a winding machine of our own design and fabrication, we have wound several prototype dipole coils with NbTi wire. As part of this development, we have repeatedly made successful persistent NbTi-NbTi joints with this multifilamentary NbTi wire. PMID:24058275

  12. Charge-induced patchy attractions between proteins.

    PubMed

    Li, Weimin; Persson, Björn A; Morin, Maxim; Behrens, Manja A; Lund, Mikael; Zackrisson Oskolkova, Malin

    2015-01-15

    Static light scattering (SLS) combined with structure-based Monte Carlo (MC) simulations provide new insights into mechanisms behind anisotropic, attractive protein interactions. A nonmonotonic behavior of the osmotic second virial coefficient as a function of ionic strength is here shown to originate from a few charged amino acids forming an electrostatic attractive patch, highly directional and complementary. Together with Coulombic repulsion, this attractive patch results in two counteracting electrostatic contributions to the interaction free energy which, by operating over different length scales, is manifested in a subtle, salt-induced minimum in the second virial coefficient as observed in both experiment and simulations. PMID:25494398

  13. Develop and test an Internally Cooled, Cabled Superconductor (ICCS) for large scale MHD magnets

    NASA Astrophysics Data System (ADS)

    Marston, P. G.; Hale, J. R.; Dawson, A. M.

    1990-04-01

    The work included four principal tasks: (1) development of a design requirements definition for a retrofit MHD magnet system; (2) analysis of an internally cooled, cabled superconductor (ICCS) to use in that design; (3) design of an experiment to test a subscale version of that conductor, which is a NbTi, copper stabilized superconductor; and (4) proof-of-concept testing of the conductor. The program was carried forth through the third task with very successful development and test of a conventional ICCS conductor with 27 multifilamentary copper-superconductor composite strands and a new concept conductor in which, in each triplet, two strands were pure copper and the third strand was a multifilamentary composite. In reviewing the magnet design and the premises for the conductor design it became obvious that an extra barrier might be highly effective in enhancing magnet stability and protection. This concept was developed and a sample conductor manufactured and tested in comparison with an identical conductor lacking such an additional barrier. Results of these conductor tests confirm the potential value of such a barrier. Since the work of tasks 1 through 3 has been reported in detail in quarterly and semiannual reports, as well as in special reports prepared throughout the course of this project, this report reviews early work briefly and then discusses this last phase in great detail.

  14. Development of SERS substrate using phage-based magnetic template for triplex assay in sepsis diagnosis.

    PubMed

    Nguyen, Anh H; Shin, Yesol; Sim, Sang Jun

    2016-11-15

    Development of a new substrate for surface-enhanced Raman scattering (SERS) is one area of interest for the improvement of SERS performance. Herein, we introduce a new method for developing new mesoporous SERS substrates using M13 phages that display cysteine-rich peptides on the pVIII major units, which is an alternative for thiol donor using chemical modifications. Together with the SERS substrate development, and the use of the SERS technique for sepsis diagnostics is a new approach in clinical settings. The substrates were characterized and magnetized with magnetic immuno colloids made of gold-coated magnetic nanoparticles and specific antibodies. Conventionally, the SERS-tags are prepared by using gold nanoparticles and are modified with Raman dyes to immobilize specific antibodies to capture the biomarkers in the serum samples. However, in this method the SERS-tags are bound to the mesoporous substrate via antibody/antigen interactions to form clusters or layer-by-layer assemblies of SERS-tags for Raman signal enhancement. The SERS spectra showed distinct peaks for tags corresponding to three typical sepsis-specific biomarkers for diagnostics with the limit of detection values of 27 pM, 103 pM, and 78 pM for C-reactive protein (CRP), procalcitonin (PCT), and soluble triggering receptor expressed on myeloid cells-1 (sTREM-1), respectively. With such an approach, SERS can be used for clinical purposes and can be improved by phage display modification rather than chemical alternatives. PMID:27209579

  15. New Developments at the XMaS Beamline For Magnetic and High Resolution Diffraction

    SciTech Connect

    Thompson, P.B.J.; Bouchenoire, L.; Brown, S.D.; Mannix, D.; Paul, D.F.; Lucas, C.; Kervin, J.; Cooper, M.J.; Arakawa, P.; Laughon, G.

    2004-05-12

    We report here on a number of developments that include enhancements of the sample environment on the XMaS beamline and the flux available at low energy. A 4 Tesla superconducting magnet has been designed to fit within the Euler cradle of a six circle Huber diffractometer, allowing scattering in both horizontal and vertical planes. The geometry of the magnet allows the application of longitudinal, transverse horizontal, and vertical fields. A further conventional magnet ({approx} 0.1 T) to minimize air absorption at low energies ({approx} 3KeV) has been designed for two circle applications, such as reflectivity. A novel in-vacuum slit screen has been developed, also minimizing absorption at low energies. New equipment for performing in-situ studies of surfaces in the electrochemical environment has been developed to allow control of the solution and sample temperature over the region of -5C to 80C. Preliminary experiments on the surface reconstructions of Au(111) in an electrolyte have been performed, whilst commissioning at the same time a MAR CCD detector for the beamline.

  16. Development of an Ultra High Frequency Gyrotron with a Pulsed Magnet

    SciTech Connect

    Idehara, T.; Kamada, M.; Tsuchiya, H.; Hayashi, T.; Agusu, La; Mitsudo, S.; Ogawa, I.; Manuilov, V. N.; Naito, K.; Yuyama, T.; Jiang, W.; Yatsui, K.

    2006-01-03

    An ultra-high frequency gyrotron is being developed as a THz radiation source by using a pulsed magnet. We have achieved the highest field intensity of 20.2 T. High frequency operation at the second harmonic will achieve 1.01 THz; the corresponding cavity mode is TE6,11,1. On the other hand, an ultra-high power gyrotron with a pulsed magnet is also being developed as a millimeter to submillimeter wave radiation source. The gyrotron is a large orbit gyrotron (LOG) using an intense relativistic electron beam (IREB). A pulsed power generator 'ETIGO-IV' is applied for generation of the IREB. A prototype relativistic LOG was constructed for fundamental operation. The output of the LOG will achieve 144 GHz and 9 MW; the corresponding cavity mode is TE1,4,1. Cavities for 2nd and 4th harmonic operations were designed by numerical simulation for achievement of higher frequency. The progress of development for prototype high frequency gyrotrons with pulsed magnets is presented.

  17. The Influence of Workplace Attraction on Recruitment and Retention

    ERIC Educational Resources Information Center

    Amundson, Norman E.

    2007-01-01

    Economic changes have made the topics of recruitment and retention key issues for career development and human resource professionals. In this article, a model of workplace attraction is presented as 1 way of better understanding the match between workers and workplaces. Many contextual variables such as age, culture, and gender influence the…

  18. Judging Books by Their Covers: Teaching about Physical Attractiveness Biases

    ERIC Educational Resources Information Center

    Kwan, Samantha; Trautner, Mary Nell

    2011-01-01

    Sociologists have developed a wide range of pedagogical strategies to facilitate student learning about racial/ethnic, class, and gender inequalities. Despite the growing subdiscipline of the sociology of the body and evidence pointing to the prevalence of inequalities based on physical attractiveness, the pedagogical literature has yet to develop…

  19. A Magnet Spring Model

    ERIC Educational Resources Information Center

    Fay, T. H.; Mead, L.

    2006-01-01

    The paper discusses an elementary spring model representing the motion of a magnet suspended from the ceiling at one end of a vertical spring which is held directly above a second magnet fixed on the floor. There are two cases depending upon the north-south pole orientation of the two magnets. The attraction or repelling force induced by the…

  20. Physical Distance and Attraction: An Intensification Effect

    ERIC Educational Resources Information Center

    Schiffenbauer, Allen; Schiavo, R. Steven

    1976-01-01

    This study was designed to test the effects of both interaction distance and the quality of the interaction upon attraction. The implications of this research for studies concerning crowding is discussed, as are possible explanatory mechanisms. (Editor/RK)

  1. Attracting and retaining nurses in HIV care.

    PubMed

    Puplampu, Gideon L; Olson, Karin; Ogilvie, Linda; Mayan, Maria

    2014-01-01

    Attracting and retaining nurses in HIV care is essential to treatment success, preventing the spread of HIV, slowing its progression, and improving the quality of life of people living with HIV. Despite the wealth of studies examining HIV care, few have focused on the factors that influenced nurses' choices to specialize in HIV care. We examined the factors that attracted and retained eight nurses currently working in HIV care in two large Canadian cities. Participants were primarily women between the ages of 20 and 60 years. Interviews were conducted between November 2010 and September 2011 using interpretive description, a qualitative design. Factors that influenced participants to focus their careers in HIV care included both attracting factors and retaining factors. Although more research is needed, this exploration of attracting and retaining factors may motivate others to specialize in HIV nursing, and thus help to promote adequate support for individuals suffering from the disease. PMID:23499392

  2. Integrating body movement into attractiveness research

    PubMed Central

    Fink, Bernhard; Weege, Bettina; Neave, Nick; Pham, Michael N.; Shackelford, Todd K.

    2015-01-01

    People judge attractiveness and make trait inferences from the physical appearance of others, and research reveals high agreement among observers making such judgments. Evolutionary psychologists have argued that interest in physical appearance and beauty reflects adaptations that motivate the search for desirable qualities in a potential partner. Although men more than women value the physical appearance of a partner, appearance universally affects social perception in both sexes. Most studies of attractiveness perceptions have focused on third party assessments of static representations of the face and body. Corroborating evidence suggests that body movement, such as dance, also conveys information about mate quality. Here we review evidence that dynamic cues (e.g., gait, dance) also influence perceptions of mate quality, including personality traits, strength, and overall attractiveness. We recommend that attractiveness research considers the informational value of body movement in addition to static cues, to present an integrated perspective on human social perception. PMID:25784887

  3. Locus of Control and Interpersonal Attraction.

    ERIC Educational Resources Information Center

    Fagan, M. Michael

    1980-01-01

    The role of locus of control in interpersonal attraction was examined by administering 1) the Nowicki-Strickland Locus of Control Scale and 2) a sociometric test of friendship to 200 eighth graders. (CM)

  4. Integrating body movement into attractiveness research.

    PubMed

    Fink, Bernhard; Weege, Bettina; Neave, Nick; Pham, Michael N; Shackelford, Todd K

    2015-01-01

    People judge attractiveness and make trait inferences from the physical appearance of others, and research reveals high agreement among observers making such judgments. Evolutionary psychologists have argued that interest in physical appearance and beauty reflects adaptations that motivate the search for desirable qualities in a potential partner. Although men more than women value the physical appearance of a partner, appearance universally affects social perception in both sexes. Most studies of attractiveness perceptions have focused on third party assessments of static representations of the face and body. Corroborating evidence suggests that body movement, such as dance, also conveys information about mate quality. Here we review evidence that dynamic cues (e.g., gait, dance) also influence perceptions of mate quality, including personality traits, strength, and overall attractiveness. We recommend that attractiveness research considers the informational value of body movement in addition to static cues, to present an integrated perspective on human social perception. PMID:25784887

  5. Electrostatic attraction between overall neutral surfaces.

    PubMed

    Adar, Ram M; Andelman, David; Diamant, Haim

    2016-08-01

    Two overall neutral surfaces with positively and negatively charged domains ("patches") have been shown in recent experiments to exhibit long-range attraction when immersed in an ionic solution. Motivated by the experiments, we calculate analytically the osmotic pressure between such surfaces within the Poisson-Boltzmann framework, using a variational principle for the surface-averaged free energy. The electrostatic potential, calculated beyond the linear Debye-Hückel theory, yields an overall attraction at large intersurface separations, over a wide range of the system's controlled length scales. In particular, the attraction is stronger and occurs at smaller separations for surface patches of larger size and charge density. In this large patch limit, we find that the attraction-repulsion crossover separation is inversely proportional to the square of the patch-charge density and to the Debye screening length. PMID:27627373

  6. Development and fabrication of a chargeable magnet system for spacecraft control

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The design of variable permanent magnets for use in magnetic balancing and control of earth orbiting spacecraft is discussed. These magnets can be used instead of air coils or electromagnets in applications where the objective is to produce, or eliminate, torque on the spacecraft through interaction with the earth's magnetic field. The configuration of the magnet for minimum size and weight is described.

  7. Alterations of the Temporomandibular Joint on Magnetic Resonance Imaging according to Growth and Development in Schoolchildren

    PubMed Central

    Tanaka, Tatsurou; Konoo, Tetsuro; Habu, Manabu; Oda, Masafumi; Kito, Shinji; Kodama, Masaaki; Kokuryo, Shinya; Wakasugi-Sato, Nao; Matsumoto-Takeda, Shinobu; Nishida, Ikuko; Morikawa, Kazumasa; Saeki, Katsura; Maki, Kenshi; Tominaga, Kazuhiro; Masumi, Shin-ichi; Terashita, Masamichi; Morimoto, Yasuhiro

    2012-01-01

    The paper explains the alterations of the temporomandibular joint (TMJ) visualized by magnetic resonance imaging (MRI) according to the growth and development of schoolchildren. Appearance and disappearance of a “double contour-like structure” (DCLS) of the mandibular condyle on MRI according to the growth and development of schoolchildren were demonstrated. In addition, possible constituents of DCLS and the significance of detection of DCLS on MRI were also speculated. The relationship between red marrow and yellow marrow in the articular eminence of temporal bone, the disappearance of DCLS, and alterations of the mandibular condyle have been elucidated. PMID:23316233

  8. Development of high frequency low weight power magnetics for aerospace power systems

    NASA Technical Reports Server (NTRS)

    Schwarze, G. E.

    1984-01-01

    A dominant design consideration in the development of space type power mangetic devices is the application of reliable thermal control methods to prevent device failure which is due to excessive temperature rises and hot temperatures in critical areas. The resultant design must also yield low weight, high efficiency, high reliability and maintainability, and long life. The weight savings and high efficiency that results by going to high frequency and unique thermal control techniques is demonstrated by the development of a 25 kVA, 20 kHz space type transformer under the power magnetics technology program. Work in the area of power rotary transformer is also discussed.

  9. Malaria Mosquitoes Attracted by Fatal Fungus

    PubMed Central

    George, Justin; Jenkins, Nina E.; Blanford, Simon; Thomas, Matthew B.; Baker, Thomas C.

    2013-01-01

    Insect-killing fungi such as Beauveria bassiana are being evaluated as possible active ingredients for use in novel biopesticides against mosquito vectors that transmit malaria. Fungal pathogens infect through contact and so applications of spores to surfaces such as walls, nets, or other resting sites provide possible routes to infect mosquitoes in and around domestic dwellings. However, some insects can detect and actively avoid fungal spores to reduce infection risk. If true for mosquitoes, such behavior could render the biopesticide approach ineffective. Here we find that the spores of B. bassiana are highly attractive to females of Anopheles stephensi, a major anopheline mosquito vector of human malaria in Asia. We further find that An. stephensi females are preferentially attracted to dead and dying caterpillars infected with B. bassiana, landing on them and subsequently becoming infected with the fungus. Females are also preferentially attracted to cloth sprayed with oil-formulated B. bassiana spores, with 95% of the attracted females becoming infected after a one-minute visit on the cloth. This is the first report of an insect being attracted to a lethal fungal pathogen. The exact mechanisms involved in this behavior remain unclear. Nonetheless, our results indicate that biopesticidal formulations comprising B. bassiana spores will be conducive to attraction and on-source visitation by malaria vectors. PMID:23658757

  10. Malaria mosquitoes attracted by fatal fungus.

    PubMed

    George, Justin; Jenkins, Nina E; Blanford, Simon; Thomas, Matthew B; Baker, Thomas C

    2013-01-01

    Insect-killing fungi such as Beauveria bassiana are being evaluated as possible active ingredients for use in novel biopesticides against mosquito vectors that transmit malaria. Fungal pathogens infect through contact and so applications of spores to surfaces such as walls, nets, or other resting sites provide possible routes to infect mosquitoes in and around domestic dwellings. However, some insects can detect and actively avoid fungal spores to reduce infection risk. If true for mosquitoes, such behavior could render the biopesticide approach ineffective. Here we find that the spores of B. bassiana are highly attractive to females of Anopheles stephensi, a major anopheline mosquito vector of human malaria in Asia. We further find that An. stephensi females are preferentially attracted to dead and dying caterpillars infected with B. bassiana, landing on them and subsequently becoming infected with the fungus. Females are also preferentially attracted to cloth sprayed with oil-formulated B. bassiana spores, with 95% of the attracted females becoming infected after a one-minute visit on the cloth. This is the first report of an insect being attracted to a lethal fungal pathogen. The exact mechanisms involved in this behavior remain unclear. Nonetheless, our results indicate that biopesticidal formulations comprising B. bassiana spores will be conducive to attraction and on-source visitation by malaria vectors. PMID:23658757

  11. Ailing Voters Advance Attractive Congressional Candidates

    PubMed Central

    Franklin, Robert G.; Palumbo, Rocco

    2015-01-01

    Among many benefits of facial attractiveness, there is evidence that more attractive politicians are more likely to be elected. Recent research found this effect to be most pronounced in congressional districts with high disease threat—a result attributed to an adaptive disease avoidance mechanism, whereby the association of low attractiveness with poor health is particularly worrisome to voters who feel vulnerable to disease. We provided a more direct test of this explanation by examining the effects of individuals’ own health and age. Supporting a disease avoidance mechanism, less healthy participants showed a stronger preference for more attractive contenders in U.S. Senate races than their healthier peers, and this effect was stronger for older participants, who were generally less healthy than younger participants. Stronger effects of health for older participants partly reflected the absence of positive bias toward attractive candidates among the healthiest, suggesting that healthy older adults may be unconcerned about disease threat or sufficiently wise to ignore attractiveness. PMID:25562113

  12. Sequential effects in face-attractiveness judgment.

    PubMed

    Kondo, Aki; Takahashi, Kohske; Watanabe, Katsumi

    2012-01-01

    A number of studies have shown that current-trial responses are biased toward the response of the preceding trial in perceptual decisionmaking tasks (the sequential effect-Holland and Lockhead, 1968 Perception & Psychophysics 3 409-414). The sequential effect has been widely observed in evaluation of the physical properties of stimuli as well as more complex properties. However, it is unclear whether subjective decisions (e.g., attractiveness judgments) are also susceptible to the sequential effect. Here, we examined whether the sequential effect would occur in face-attractiveness judgments. Forty-eight pictures of male and female faces were presented successively. Participants rated the attractiveness of each face on a 7-point scale. The results showed that the attractiveness rating of a given face assimilated toward the rating of the preceding trial. In a separate experiment, we provided the average attractiveness rating by others for each trial as feedback. The feedback weakened the sequential effect. These findings suggest that attractiveness judgment is also biased toward the preceding judgment, and hence the sequential effect can be extended into the domain of subjective decisionmaking. PMID:22611662

  13. On the Development of a Magnetically Vectored Variable ISP Plasma Rocket

    NASA Technical Reports Server (NTRS)

    Feliciano, Enectali Figueroa; Diaz, Franklin R. Chang; Squire, Jared P.

    1997-01-01

    The development of a Magnetically Vectored Variable I(sub sp) Plasma Rocket at the Advanced Space Propulsion Laboratory (ASPL) is in progress at NASA's Johnson Space Center. The facility is using a small, 3.2 m tandem mirror device to study the application of RF heated magnetically contained plasmas for space propulsion. The central cell radius is 0.1 m and fields of 0.2 T and 2 T are possible in the central and end-cell mirror sections, respectively. A magnetoplasmadynamic (MPD) injector has just been acquired and will be used along with other methods of plasma refueling. A 1 MW magnet power supply upgrade is being developed with full implementation by the Spring of 1997. Two microwave systems for discharge initiation and plasma heating at 2.45 GHz and 14.0 GHz, respectively, are in operation. Additionally, RF systems with 200 kW and 1 MW of power are being modified and conditioned for operation. The concept provides electrode-less operation and variable thrush'specific impulse at constant power (200 -30 N /5000-30,000 seconds at 10 MW with a 60% efficiency). Optimization for speed or payload are possible with the same engine, giving the rocket great flexibility. Missions to Mars in 90 days are described, and missions to Pluto are under study.

  14. Development of magnetic luminescent core/shell nanocomplex particles with fluorescence using Rhodamine 6G

    SciTech Connect

    Lee, Hee Uk; Song, Yoon Seok; Park, Chulhwan; Kim, Seung Wook

    2012-12-15

    Graphical abstract: Display Omitted Highlights: ► A simple method was developed to synthesize Co-B/SiO{sub 2}/dye/SiO{sub 2} composite particles. ► The magnetic particle shows that highly luminescent and core/shell particles are formed. ► Such core/shell particles can be easily suspended in water. ► The magnetic particles could detect fluorescence for the application of biosensor. -- Abstract: A simple and reproducible method was developed to synthesize a novel class of Co-B/SiO{sub 2}/dye/SiO{sub 2} composite core/shell particles. Using a single cobalt core, Rhodamine 6G of organic dye molecules was entrapped in a silica shell, resulting in core/shell particles of ∼200 nm diameter. Analyses using a variety of techniques such as transmission electron microscopy, X-ray photoelectron spectroscopy, vibration sample magnetometry, confocal laser scanning microscopy, and fluorescence intensity demonstrated that dye molecules were trapped inside the core/shell particles. A photoluminescence investigation showed that highly luminescent and photostable core/shell particles were formed. Such core/shell particles can be easily suspended in water. The synthesized magnetic particles could be used to detect fluorescence on glass substrate arrays for bioassay and biosensor applications.

  15. Development of a magnetic nanoparticles microarray for simultaneous and simple detection of foodborne pathogens.

    PubMed

    Li, Song; Liu, Hongna; Deng, Yan; Lin, Lin; He, Nongyue

    2013-07-01

    Foodborne diseases are a widespread and growing public health problem affecting both developed and developing countries, microbiologically contaminated food and water are the major causes of diarrhoeal diseases. Methods based on polymerase chain reaction (PCR) and microarrays are rapid and sensitive enough to detect very small quantities of microorganisms, however, the requirement for expensive equipments limits their application. In the present paper, we describe a method based on multiplex PCR and magnetic nanoparticles labelling for simultaneous detection of four major foodborne pathogens, including Escherichia coli O157:H7, Salmonella enterica, Vibrio cholera and Campylobacter jejuni. The process utilizes an oligonucleotide array onto which 5' biotinylated single strand PCR products were hybridized and visualized with streptavidin-coated magnetic nanoparticles (SA-MNPs), the signal from which could be detected by the naked eye, microscope or CCD camera. By employing SA-MNPs as visible labels, the microarray unambiguously distinguished all 4 pathogens with detection sensitivity up to 316 CFU/mL. Due to its high sensitivity, specificity and simple detection procedure, the magnetic bead assay provides a powerful tool for the detection and identification of foodborne pathogens in a modestly equipped laboratory. PMID:23909141

  16. Downtown Elementary School (DES): The Unique School That Juxtaposes Both Magnet and Professional Development School (PDS) Programs

    ERIC Educational Resources Information Center

    Alenuma, Sidonia

    2009-01-01

    The objective of this paper is to explore the operation of magnet and professional development school (PDS) programs in a real life situation using an ethnographic study of Downtown Elementary School (DES--a pseudonym) that simultaneously operates as a PDS and a magnet school. The author spent almost three years at DES, located in the Southern…

  17. Three-Dimensional Magnetic Analysis Technique Developed for Evaluating Stirling Convertor Linear Alternators

    NASA Technical Reports Server (NTRS)

    Geng, Steven M.

    2003-01-01

    The Department of Energy, the Stirling Technology Company (STC), and the NASA Glenn Research Center are developing Stirling convertors for Stirling radioisotope generators to provide electrical power for future NASA deep space missions. STC is developing the 55-We technology demonstration convertor (TDC) under contract to the Department of Energy. The Department of Energy recently named Lockheed Martin as the system integration contractor for the Stirling radioisotope generator development project. Lockheed Martin will develop the Stirling radioisotope generator engineering unit and has contract options to develop the qualification unit and the first flight unit. Glenn s role includes an in-house project to provide convertor, component, and materials testing and evaluation in support of the overall power system development. As a part of this work, Glenn has established an in-house Stirling research laboratory for testing, analyzing, and evaluating Stirling machines. STC has built four 55-We convertors for NASA, and these are being tested at Glenn. A cross-sectional view of the 55-We TDC is shown in the figure. Of critical importance to the successful development of the Stirling convertor for space power applications is the development of a lightweight and highly efficient linear alternator. In support, Glenn has been developing finite element analysis and finite element method tools for performing various linear alternator thermal and electromagnetic analyses and evaluating design configurations. A three-dimensional magnetostatic finite element model of STC's 55-We TDC linear alternator was developed to evaluate the demagnetization fields affecting the alternator magnets. Since the actual linear alternator hardware is symmetric to the quarter section about the axis of motion, only a quarter section of the alternator was modeled. The components modeled included the mover laminations, the neodymium-iron-boron magnets, the stator laminations, and the copper coils. The

  18. Development of a low-cost double rotor axial flux motor with soft magnetic composite and ferrite permanent magnet materials

    NASA Astrophysics Data System (ADS)

    Liu, Chengcheng; Zhu, Jianguo; Wang, Youhua; Guo, Youguang; Lei, Gang; Liu, Xiaojing

    2015-05-01

    This paper proposes a low-cost double rotor axial flux motor (DRAFM) with low cost soft magnetic composite (SMC) core and ferrite permanent magnets (PMs). The topology and operating principle of DRAFM and design considerations for best use of magnetic materials are presented. A 905 W 4800 rpm DRAFM is designed for replacing the high cost NdFeB permanent magnet synchronous motor (PMSM) in a refrigerator compressor. By using the finite element method, the electromagnetic parameters and performance of the DRAFM operated under the field oriented control scheme are calculated. Through the analysis, it is shown that that the SMC and ferrite PM materials can be good candidates for low-cost electric motor applications.

  19. Development of the axial gap type motor/generator for the flywheel with superconducting magnetic bearings

    NASA Astrophysics Data System (ADS)

    Nagaya, S.; Kashima, N.; Kawashima, H.; Kakiuchi, Y.; Hoshino, A.; Isobe, S.

    2003-10-01

    Flywheel with superconducting magnetic bearings requires the characteristics for the motor/generator such as lower loss, higher efficiency, lower bearing load and more displacement tolerance of the radial directions. We developed an extremely flat shape axial gap type motor/generator which consists of a rotor with permanent magnets and slotless windings to satisfy these characteristics. We introduced the system for adjusting intensity of the excitation to decrease the eddy current loss during the storage and to get the controllability of electromotive force for variable speed operation during charging and discharging. We manufactured the motor/generator of output power 17 kW at 10,000 rpm. It was tested to perform the fundamental functions of motor and generator at partial speeds up to 4000 rpm.

  20. Development and application of setup for ac magnetic field in neutron scattering experiments.

    PubMed

    Klimko, Sergey; Zhernenkov, Kirill; Toperverg, Boris P; Zabel, Hartmut

    2010-10-01

    We report on a new setup developed for neutron scattering experiments in periodically alternating magnetic fields at the sample position. The assembly consisting of rf generator, amplifier, wide band transformer, and resonance circuit. It allows to generate homogeneous ac magnetic fields over a volume of a few cm(3) and variable within a wide range of amplitudes and frequencies. The applicability of the device is exemplified by ac polarized neutron reflectometry (PNR): a new method established to probe remagnetization kinetics in soft ferromagnetic films. Test experiments with iron films demonstrate that the ac field within the accessible range of frequencies and amplitudes produces a dramatic effect on the PNR signal. This shows that the relevant ac field parameters generated by the device match well with the scales involved in the remagnetization processes. Other possible applications of the rf unit are briefly discussed. PMID:21034083

  1. Development and application of setup for ac magnetic field in neutron scattering experiments

    SciTech Connect

    Klimko, Sergey; Zhernenkov, Kirill; Toperverg, Boris P.; Zabel, Hartmut

    2010-10-15

    We report on a new setup developed for neutron scattering experiments in periodically alternating magnetic fields at the sample position. The assembly consisting of rf generator, amplifier, wide band transformer, and resonance circuit. It allows to generate homogeneous ac magnetic fields over a volume of a few cm{sup 3} and variable within a wide range of amplitudes and frequencies. The applicability of the device is exemplified by ac polarized neutron reflectometry (PNR): a new method established to probe remagnetization kinetics in soft ferromagnetic films. Test experiments with iron films demonstrate that the ac field within the accessible range of frequencies and amplitudes produces a dramatic effect on the PNR signal. This shows that the relevant ac field parameters generated by the device match well with the scales involved in the remagnetization processes. Other possible applications of the rf unit are briefly discussed.

  2. Development of a mobile magnetic resonance imaging system for outdoor tree measurements

    NASA Astrophysics Data System (ADS)

    Kimura, Takeshi; Geya, Yuto; Terada, Yasuhiko; Kose, Katsumi; Haishi, Tomoyuki; Gemma, Hiroshi; Sekozawa, Yoshihiko

    2011-05-01

    By combining a 0.3 T permanent magnet with flexible rotation and translation mechanism, a probe with a local electromagnetic shielding, several electrical units, a mobile lift, and an electric wagon, a mobile magnetic resonance imaging (MRI) system was developed for outdoor tree measurements. 2D cross-sectional images of normal and diseased branches of a pear tree were acquired for measurements of T1, T2, proton density, and apparent diffusion constant (ADC). The ADC map clearly differentiated diseased from normal branches. A whole-day measurement of the ADC map demonstrated that microscopic water flow in the normal branch changed proportionally with solar radiation. Therefore, we have concluded that our mobile MRI system is a powerful tool for studies of plants in outdoor environments.

  3. Development of a local electromagnetic shielding for an extremity magnetic resonance imaging system

    NASA Astrophysics Data System (ADS)

    Handa, Shinya; Haishi, Tomoyuki; Kose, Katsumi

    2008-11-01

    A local radio frequency (rf) shielding consisting of a Cu plate and an LC balun circuit has been developed for a compact magnetic resonance imaging (MRI) system with a 0.3 T permanent magnet. Performance of the local rf shielding was evaluated using an artificial external noise source irradiating a human subject whose hand was inserted into the rf coil of the MRI system. Power spectra of the rf signal detected through the rf coil demonstrated that the local rf shield achieved 30.1 dB external noise suppression. With the local rf shielding, a MRI of the subject's hand was performed using a three-dimensional gradient-echo sequence. Anatomical structures of the subject's hand were clearly visualized. It was concluded that the local rf shielding could be used for the compact MRI system instead of a rf shielded room.

  4. Development of Large Bismuth Absorbers for Magnetic Calorimeters Applied to Hard X-ray Spectrometry

    NASA Astrophysics Data System (ADS)

    Rodrigues, M.; Loidl, M.; Pies, C.; Fleischmann, A.; Enss, C.

    2014-08-01

    Bismuth is an interesting material for magnetic calorimeter absorbers applied to high energy resolution X-ray spectrometry; it has a low specific heat and high atomic number. However, past detector developments with Bi absorbers were confronted with the low thermal conductivity of bismuth that degraded the energy resolution and deformed the detector response function (non-Gaussian energy peak). In the present study, we have investigated the performances of large bulk bismuth absorbers ( mm) thermally coupled to metallic magnetic sensors. Despite a very good baseline energy resolution, detectors with monolithic bismuth absorbers have degraded FWHM energy resolutions with any type of thermal coupling between the absorber and the sensor tested. In comparison tests with BiCu and BiAg bilayer absorbers demonstrated much better performances.

  5. Development of flexible array eddy current probes for complex geometries and inspection of magnetic parts using magnetic sensors

    NASA Astrophysics Data System (ADS)

    Marchand, B.; Decitre, J.-M.; Sergeeva-Chollet, N.; Skarlatos, A.

    2013-01-01

    Eddy Current Technique is a powerful method of inspection of metal parts. When size of flaws decreases, inspection areas become hardly accessible or material is magnetic, traditional winding coil probes are less efficient. Thanks to new CIVA simulation tools, we have designed and optimized advanced EC probes: flexible EC probe based on micro-coil arrays and EC probe with magnetic sensors, including specific electronics.

  6. Longevity of Pheromone and Co-attractant Lures Used in Attract-and-Kill Stations for Control of Carpophilus Beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field longevity of synthetic lures for Carpophilus spp. beetles was evaluated by trapping studies in Australia, accompanied by chemical analyses. Carpophilus beetles are serious pests of ripening fruits, and an attract-and-kill method has been developed for their control. Traps are baited with two...

  7. Defining the brain systems of lust, romantic attraction, and attachment.

    PubMed

    Fisher, Helen E; Aron, Arthur; Mashek, Debra; Li, Haifang; Brown, Lucy L

    2002-10-01

    Mammals and birds have evolved three primary, discrete, interrelated emotion-motivation systems in the brain for mating, reproduction, and parenting: lust, attraction, and male-female attachment. Each emotion-motivation system is associated with a specific constellation of neural correlates and a distinct behavioral repertoire. Lust evolved to initiate the mating process with any appropriate partner; attraction evolved to enable individuals to choose among and prefer specific mating partners, thereby conserving their mating time and energy; male-female attachment evolved to enable individuals to cooperate with a reproductive mate until species-specific parental duties have been completed. The evolution of these three emotion-motivation systems contribute to contemporary patterns of marriage, adultery, divorce, remarriage, stalking, homicide and other crimes of passion, and clinical depression due to romantic rejection. This article defines these three emotion-motivation systems. Then it discusses an ongoing project using functional magnetic resonance imaging of the brain to investigate the neural circuits associated with one of these emotion-motivation systems, romantic attraction. PMID:12238608

  8. Electronic Phase Exhibits Attraction Between Like Net Charges

    NASA Astrophysics Data System (ADS)

    Manz, Thomas

    A new electronic phase transition was observed in thin plastic films metallized with gold, optionally with an additional layer of aluminum metallization. This phase transition occurred only when the dielectric layers of two metallized films faced each other. When charged to high voltage magnitudes and then grounded, an electronic phase transition occurred during the discharge step that led to a strong attraction between the paired metallized films, even though the films carried like net charges. The resulting electronic phase (and its attractive force) persisted for several days with no apparent decay at ambient temperatures (c. 25 C). After rotating the films along an axis not parallel to the films, the magnetic field due to rotational motion of the charge carriers relative to the thin films persisted for seconds before dissipation. This demonstrates free current lifetimes lasting seconds. Computations and experiments were performed that show the underlying mechanism for the attraction of like net charges is scattering of electromagnetic waves by an electric field cusp at the charged interfaces. Scattering theory calculations reveal this scattering should be most prevalent in the infrared and microwave regions. This has potential applications for shielding electronic circuits from electromagnetic noise at these wavelengths.

  9. Comparison of non-magnetic and magnetic beads in bead-based assays.

    PubMed

    Hansenová Maňásková, Silvie; van Belkum, Alex; Endtz, Hubert P; Bikker, Floris J; Veerman, Enno C I; van Wamel, Willem J B

    2016-09-01

    Multiplex bead-based flow cytometry is an attractive way for simultaneous, rapid and cost-effective analysis of multiple analytes in a single sample. Previously, we developed various bead-based assays using non-magnetic beads coated with Staphylococcus aureus and Streptococcus pneumoniae antigens for the detection of antibodies. Here, we compared the performance of the assay using non-magnetic beads with one based on the newly developed magnetic beads. We optimized the magnetic beads' coupling procedure and antibody detection assays for S. aureus and S. pneumoniae antigens and we measured IgG in human pooled serum against a series of S. aureus and S. pneumoniae-derived antigens in a singleplex and in a multiplex assay, respectively. For the multiplex assay, the comparison between magnetic and non-magnetic beads showed: i) in the majority of the cases (13 of the 17 tested S. pneumoniae antigens) significantly higher Median Fluorescence Intensity (MFI) values, ii) lower detection limits, iii) lower coefficient of variation (CV: 12% vs. 7% for non-magnetic vs. magnetic beads), so lower inter-assay variation and hence higher reproducibility. Magnetic bead coupling is cost effective, as we used 25% of the normal amount of antigen and only 50% of the beads in comparison to the non-magnetic beads. This optimized magnetic-based assay, which combines ease of use with an improved assay performance, allows detection of antibodies with a low titer that are potentially missed with the non-magnetic-based assay. PMID:27296810

  10. Mathematical modelling for trajectories of magnetic nanoparticles in a blood vessel under magnetic field

    NASA Astrophysics Data System (ADS)

    Sharma, Shashi; Katiyar, V. K.; Singh, Uaday

    2015-04-01

    A mathematical model is developed to describe the trajectories of a cluster of magnetic nanoparticles in a blood vessel for the application of magnetic drug targeting (MDT). The magnetic nanoparticles are injected into a blood vessel upstream from a malignant tissue and are captured at the tumour site with help of an applied magnetic field. The applied field is produced by a rare earth cylindrical magnet positioned outside the body. All forces expected to significantly affect the transport of nanoparticles were incorporated, including magnetization force, drag force and buoyancy force. The results show that particles are slow down and captured under the influence of magnetic force, which is responsible to attract the magnetic particles towards the magnet. It is optimized that all particles are captured either before or at the centre of the magnet (z≤0) when blood vessel is very close proximity to the magnet (d=2.5 cm). However, as the distance between blood vessel and magnet (d) increases (above 4.5 cm), the magnetic nanoparticles particles become free and they flow away down the blood vessel. Further, the present model results are validated by the simulations performed using the finite element based COMSOL software.

  11. EDITORIAL: Opposites attract: nanomagnetism in theory and practice Opposites attract: nanomagnetism in theory and practice

    NASA Astrophysics Data System (ADS)

    Demming, Anna

    2012-09-01

    Putting theory into practice in nanotechnology can be far from trivial. Magnetic artificial atoms have been an example of the gulf that can sometimes separate idea from experiment. The step from regular semiconductor artificial atoms to magnetic may not confound the imagination, but it poses no mean fabrication challenge to experimental physicists. In this issue researchers in Germany have successfully fabricated a magnetic artificial atom [1]. As the researchers point out, the systems look promising for further study of the transport properties of 0D magnetic objects. Magnetic behavior in nanoscale systems has inspired a number of technological developments, such as energetically efficient digital logic circuitry [2]. Theory dictates that less energy is dissipated in the manipulation of nanomagnet logic bits than in the manipulation of electrical charges in transistor switches. Among the challenges when putting this into practice is the issue of sequential clocking. The nanomagnets' polarizations need to be rotated through 90° from the easy to the hard axis ready to be set before propagating the logic bits from one stage to the next. Ideally this would be a localized process to allow the efficiencies of a pipe-line computer architecture. Researchers at Virginia Commonwealth University in the US showed that a small voltage applied to a multiferroic nanomagnet can cause this polarization rotation [3]. They further showed that the switching delay of this process is not impracticably long, suggesting that the process is promising for logic circuits that are very fast as well as energy efficient [4]. Researchers in Germany have demonstrated magnetic force microscopy for high resolution imaging using a carbon nanotube filled with iron [5]. A magnetic dipole moment in the iron extends from end to end of the iron nanowire in the carbon nanotube. As a result of the extreme aspect ratio of the nanowire only the pole at one end is involved in the imaging process. The

  12. Development of marine magnetic vector measurement system using AUV and deep-towed vehicle

    NASA Astrophysics Data System (ADS)

    Sayanagi, K.; Isezaki, N.; Matsuo, J.; Harada, M.; Kasaya, T.; Nishimura, K.; Baba, H.

    2012-04-01

    Marine magnetic survey is one of useful methods in order to investigate the nature of the oceanic crust. Most of the data are, however, intensity of the geomagnetic field without its direction. Therefore we cannot properly apply a physical formula describing the relation between magnetic field and magnetization to analyses of the data. With this problem, Isezaki (1986) developed a shipboard three-component magnetometer which measures the geomagnetic vector at the sea. On the other hand, geophysical surveys near the seafloor have been more and more necessary in order to show the details of the oceanic crust. For instance, development of seabed resources like hydrothermal deposits needs higher resolution surveys compared with conventional surveys at the sea for accurate estimation of abundance of the resources. From these viewpoints, we have been developing a measurement system of the deep-sea geomagnetic vector using AUV and deep-towed vehicle. The measurement system consists of two 3-axis flux-gate magnetometers, an Overhauser magnetometer, an optical fiber gyro, a main unit (control, communication, recording), and an onboard unit. These devices except for the onboard unit are installed in pressure cases (depth limit: 6000m). Thus this measurement system can measure three components and intensity of the geomagnetic field in the deep-sea. In 2009, the first test of the measurement system was carried out in the Kumano Basin using AUV Urashima and towing vehicle Yokosuka Deep-Tow during the R/V Yokosuka YK09-09 cruise. In this test, we sank a small magnetic target to the seafloor, and examined how the system worked. As a result, we successfully detected magnetic anomaly of the target to confirm the expected performance of that in the sea. In 2010, the measurement system was tested in the Bayonnaise Knoll area both using a titanium towing frame during the R/V Bosei-maru cruise and using AUV Urashima during the R/V Yokosuka YK10-17 cruise. The purpose of these tests was

  13. Vehicle with magnetic engine

    SciTech Connect

    Wortham, C.

    1993-06-15

    A vehicle is described comprising a vehicle frame fitted with axles and wheels rotatably carried by the axles; an engine block mounted on the frame; a plurality of magnetic cylinders provided in the engine block and a plurality of magnetic pistons disposed in the magnetic cylinders, respectively, in reciprocating relationship, the magnetic cylinders having a first magnetic polarity in one end and a second magnetic polarity in the opposite end for alternately attracting and repelling the magnetic pistons, respectively; a crankshaft journalled for rotation in the engine block; power transmission means connecting the crankshaft to at least one of the axles in driving relationship; and connecting rods connecting the crankshaft to the magnetic pistons, respectively, whereby reciprocation of the magnetic pistons in the magnetic cylinders effects rotation of the crankshaft; a cylinder head provided on the engine block and piston electromagnetic means provided in the cylinder head above the magnetic cylinders and the magnetic pistons, respectively for alternately attracting and repelling the magnetic pistons; at least one battery carried by the frame; and polarity timing means electrically connected to the battery and the piston electromagnetic means, for alternating the polarity of the piston electromagnet means, whereby electric current is supplied to the piston electromagnetic means in current-reversing relationship to alternately attract and repel the magnetic pistons in reciprocating relationship responsive to operation of the polarity timing means.

  14. May the Magnetic Force Be with You

    ERIC Educational Resources Information Center

    Wilcox, Jesse; Richey, Lindsey R.

    2012-01-01

    Although most elementary students have had experiences with magnets, they generally have misconceptions about magnetism (Driver et al. 1994; Burgoon, Heddle, and Duran 2010). For example, students may think magnets can attract all metals or that larger magnets are stronger than smaller magnets. Students often confuse magnets with magnetic…

  15. Gravitational mass attraction measurement for drag-free references

    NASA Astrophysics Data System (ADS)

    Swank, Aaron J.

    this research is therefore to develop the necessary equations for the gravitational mass attraction force and gradients between two general distributed bodies. Assuming the drag-free reference mass to be a single point mass object is no longer necessary for the gravitational attraction calculations. Furthermore, the developed equations are coupled with physical measurements in order to eliminate the mass attraction uncertainty associated with mass properties. The mass attraction formula through a second order expansion consists of the measurable quantifies of mass, mass center, and moment of inertia about the mass center. Thus, the gravitational self-attraction force on the drag free reference due to the satellite can be indirectly measured. By incorporating physical measurements into the mass attraction calculation, the uncertainty in the density distribution as well as geometrical variations due to the manufacturing process are included in the analysis. For indirect gravitational mass attraction measurements, the corresponding properties of mass, mass center, and moment of inertia must be precisely determined for the proof mass and satellite components. This work focuses on the precision measurement of the moment of inertia for the drag-free test mass. Presented here is the design of a new moment of inertia measurement apparatus utilizing a five-wire torsion pendulum design. The torsion pendulum is utilized to measure the moment of inertia tensor for a prospective drag-free test mass geometry. The measurement results presented indicate the prototype five-wire torsion has matched current state of the art precision. With only minimal work to reduce laboratory environmental disturbances, the apparatus has the prospect of exceeding state of the art precision by almost an order of magnitude. In addition, the apparatus is shown to be capable of measuring the mass center offset from the geometric center to a level better than typical measurement devices. Although the

  16. Photogrammetric Analysis of Attractiveness in Indian Faces

    PubMed Central

    Duggal, Shveta; Kapoor, DN; Verma, Santosh; Sagar, Mahesh; Lee, Yung-Seop; Moon, Hyoungjin

    2016-01-01

    Background The objective of this study was to assess the attractive facial features of the Indian population. We tried to evaluate subjective ratings of facial attractiveness and identify which facial aesthetic subunits were important for facial attractiveness. Methods A cross-sectional study was conducted of 150 samples (referred to as candidates). Frontal photographs were analyzed. An orthodontist, a prosthodontist, an oral surgeon, a dentist, an artist, a photographer and two laymen (estimators) subjectively evaluated candidates' faces using visual analog scale (VAS) scores. As an objective method for facial analysis, we used balanced angular proportional analysis (BAPA). Using SAS 10.1 (SAS Institute Inc.), the Turkey's studentized range test and Pearson correlation analysis were performed to detect between-group differences in VAS scores (Experiment 1), to identify correlations between VAS scores and BAPA scores (Experiment 2), and to analyze the characteristic features of facial attractiveness and gender differences (Experiment 3); the significance level was set at P=0.05. Results Experiment 1 revealed some differences in VAS scores according to professional characteristics. In Experiment 2, BAPA scores were found to behave similarly to subjective ratings of facial beauty, but showed a relatively weak correlation coefficient with the VAS scores. Experiment 3 found that the decisive factors for facial attractiveness were different for men and women. Composite images of attractive Indian male and female faces were constructed. Conclusions Our photogrammetric study, statistical analysis, and average composite faces of an Indian population provide valuable information about subjective perceptions of facial beauty and attractive facial structures in the Indian population. PMID:27019809

  17. Development of a simple pressure and heat stimulator for intra- and interdigit functional magnetic resonance imaging.

    PubMed

    Kim, Hyung-Sik; Choi, Mi-Hyun; Kim, Hyun-Joo; Hong, Sang-Pyo; Park, Jang-Yeon; Jun, Jae-Hoon; Yi, Jeong-Han; Chung, Yoon-Gi; Kim, Sung-Phil; Park, Jong-Rak; Lim, Dae-Woon; Chung, Soon-Cheol

    2014-06-01

    For this study, we developed a simple pressure and heat stimulator that can quantitatively control pressure and provide heat stimulation to intra- and interdigit areas. The developed stimulator consists of a control unit, drive units, and tactors. The control unit controls the stimulation parameters, such as stimulation types, intensity, time, and channel, and transmits a created signal of stimulation to the drive units. The drive units operate pressure and heat tactors in response to commands from the control unit. The pressure and heat tactors can display various stimulation intensities quantitatively, apply stimulation continuously, and adjust the stimulation areas. Additionally, they can easily be attached to and detached from the digits. The developed pressure and heat stimulator is small in total size, easy to install, and inexpensive to manufacture. The new stimulator operated stably in a magnetic resonance imaging (MRI) environment without affecting the obtained images. A preliminary functional magnetic resonance imaging (fMRI) experiment confirmed that differences in activation of somatosensory areas were induced from the pressure and heat stimulation. The developed pressure and heat stimulator is expected to be utilized for future intra- and interdigit fMRI studies on pressure and heat stimulation. PMID:23861087

  18. Development of Position-Sensitive Magnetic Calorimeter X-ray Detectors

    NASA Astrophysics Data System (ADS)

    Porst, Jan-Patrick; Bandler, Simon R.; Adams, Joseph S.; Hsieh, Wen-Ting; Rotzinger, Hannes; Seidel, George M.; Smith, Stephen J.; Stevenson, Thomas R.

    2009-12-01

    We are developing arrays of position-sensitive magnetic calorimeter (PoSM) X-ray detectors for future astronomy missions. The PoSM consists of multiple absorbers thermally coupled to one magnetic sensor. Each absorber element has a different thermal coupling to the sensor. This results in a distribution of different pulse shapes and enables position discrimination between the absorber elements. PoSMs are motivated by the desire to achieve the largest possible focal plane area with the fewest number of readout channels without compromising on spatial sampling. Optimizing the performance of PoSMs requires careful design of key parameters such as the thermal conductances between the absorbers, magnetic sensor and the heat sink, as well as the absorber heat capacities. We report on the first experimental results from four-absorber PoSMs, each absorber consisting of a two layer composite of bismuth and gold. The measured energy resolution (FWHM) was less than 5 eV for 6 keV X-rays into all four absorbers. Straightforward position discrimination by means of rise-time is also demonstrated.

  19. The Development of a Noncontact Letter Input Interface “Fingual” Using Magnetic Dataset

    NASA Astrophysics Data System (ADS)

    Fukushima, Taishi; Miyazaki, Fumio; Nishikawa, Atsushi

    We have newly developed a noncontact letter input interface called “Fingual”. Fingual uses a glove mounted with inexpensive and small magnetic sensors. Using the glove, users can input letters to form the finger alphabets, a kind of sign language. The proposed method uses some dataset which consists of magnetic field and the corresponding letter information. In this paper, we show two recognition methods using the dataset. First method uses Euclidean norm, and second one additionally uses Gaussian function as a weighting function. Then we conducted verification experiments for the recognition rate of each method in two situations. One of the situations is that subjects used their own dataset; the other is that they used another person's dataset. As a result, the proposed method could recognize letters with a high rate in both situations, even though it is better to use their own dataset than to use another person's dataset. Though Fingual needs to collect magnetic dataset for each letter in advance, its feature is the ability to recognize letters without the complicated calculations such as inverse problems. This paper shows results of the recognition experiments, and shows the utility of the proposed system “Fingual”.

  20. Development and testing of a magnetic position sensor system for automotive and avionics applications

    NASA Astrophysics Data System (ADS)

    Jacobs, Bryan C.; Nelson, Carl V.

    2001-08-01

    A magnetic sensor system has been developed to measure the 3-D location and orientation of a rigid body relative to an array of magnetic dipole transmitters. A generalized solution to the measurement problem has been formulated, allowing the transmitter and receiver parameters (position, orientation, number, etc.) to be optimized for various applications. Additionally, the method of images has been used to mitigate the impact of metallic materials in close proximity to the sensor. The resulting system allows precise tracking of high-speed motion in confined metal environments. The sensor system was recently configured and tested as an abdomen displacement sensor for an automobile crash-test dummy. The test results indicate a positional accuracy of approximately 1 mm rms during 20 m/s motions. The dynamic test results also confirmed earlier covariance model predictions, which were used to optimize the sensor geometry. A covariance analysis was performed to evaluate the applicability of this magnetic position system for tracking a pilot's head motion inside an aircraft cockpit. Realistic design parameters indicate that a robust tracking system, consisting of lightweight pickup coils mounted on a pilot's helmet, and an array of transmitter coils distributed throughout a cockpit, is feasible. Recent test and covariance results are presented.

  1. Development of Position-Sensitive Magnetic Calorimeter X-ray Detectors

    SciTech Connect

    Porst, Jan-Patrick; Bandler, Simon R.; Adams, Joseph S.; Smith, Stephen J.; Hsieh, W.-T.; Stevenson, Thomas R.; Rotzinger, Hannes; Seidel, George M.

    2009-12-16

    We are developing arrays of position-sensitive magnetic calorimeter (PoSM) X-ray detectors for future astronomy missions. The PoSM consists of multiple absorbers thermally coupled to one magnetic sensor. Each absorber element has a different thermal coupling to the sensor. This results in a distribution of different pulse shapes and enables position discrimination between the absorber elements. PoSMs are motivated by the desire to achieve the largest possible focal plane area with the fewest number of readout channels without compromising on spatial sampling. Optimizing the performance of PoSMs requires careful design of key parameters such as the thermal conductances between the absorbers, magnetic sensor and the heat sink, as well as the absorber heat capacities. We report on the first experimental results from four-absorber PoSMs, each absorber consisting of a two layer composite of bismuth and gold. The measured energy resolution (FWHM) was less than 5 eV for 6 keV X-rays into all four absorbers. Straightforward position discrimination by means of rise-time is also demonstrated.

  2. Development of Ni-Zn nanoferrite core material with improved saturation magnetization and DC resistivity

    NASA Astrophysics Data System (ADS)

    Kumar, A. Mahesh; Varma, M. Chaitanya; Dube, Charu Lata; Rao, K. H.; Kashyap, Subhash C.

    Nanostructured Nickel-Zinc ferrite of composition Ni 0.65Zn 0.35Fe 2O 4 was prepared by sol-gel, co-precipitation, citrate-gel and oxalate precursor methods. X-ray diffraction (XRD) patterns of all the samples showed the spinel structure. A comparison of average crystallite size clearly indicated that the sol-gel method was the effective one in producing small crystallite sized samples having insignificant variation with annealing or sintering temperatures. Also, sol-gel method was observed to provide high saturation magnetization values in samples sintered even at lower temperatures. The high magnetization values are, in general, reported in bulk samples prepared at higher sintering temperatures by conventional ceramic method. Direct-current (DC) resistivity of these samples was also considerably improved as compared to that of the bulk materials. Discussion has been made on the basis of observed higher values of saturation magnetization and dc resistivity towards the development of a high-quality core material useful for high-frequency applications.

  3. Preparation of a Magnetically Switchable Bioelectrocatalytic System Employing Cross-Linked Enzyme Aggregates in Magnetic Mesocellular Carbon Foam

    SciTech Connect

    Lee, Jinwoo; Lee, Dohun; Oh, Eunkeu; Kim, Jaeyun; Kim, Young-Pil; Jin, Sunmi; Kim, Hak Sung; Hwang, Yosun; Kwak, Ja Hun; Park, Je-Geun; Shin, Chae-Ho; Kim, Jungbae; Hyeon, Taeghwan

    2005-11-18

    Nanostructured magnetic materials (NMMs)[1] have attracted much attention recently because of their broad biotechnological applications including support matrices for enzyme immobilization,[2] immunoassays,[3] drug delivery,[4] and biosensors.[ 5] Specifically, the easy separation and controlled placement of NMMs by means of an external magnetic field enables their application in the development of immobilized enzyme processes[2] and the construction of magnetically controllable bio-electrocatalytic systems.[5, 6] Herein, we demonstrate the use of immobilized enzymes in NMMs for magnetically switchable bio-electrocatalysis.

  4. Development of two-stage solidification technology for implementing micro structures with liquid magnetic polymer and solid magnetic anisotropic polymer

    NASA Astrophysics Data System (ADS)

    Hsu, Fu-Ming; Fang, Weileun

    2014-09-01

    This study presents two-stage solidification technology for fabricating micromagnetic polymer composite (MPC, polymer with magnetic particles) structures. In this process, ultra-violet (UV)-light polymer curing is used for the first stage of MPC solidification. The surface of the MPC structure is solidified in this step. Moreover, thermal polymer curing is employed for the second stage of MPC solidification. The second stage of curing was mainly for the body solidification of the MPC. The distribution of magnetic particles in MPC can be specified by applying a magnetic field during the second solidification process. Based on the presented process technologies, microstructures with liquid MPC (NdFeB particles of different wt% in liquid polymer), isotropic solid MPC and anisotropic solid MPC have been demonstrated. Microdevices with liquid MPC embedded in solid micro balls and thin layers are also demonstrated. Various tests are performed to characterize the magnetic properties of the fabricated micro MPC structures. Measurements show that the fabricated solid MPC has reasonable coercivity, as compared with bulk materials. However, the remanence and the saturation magnetization still need to be improved.

  5. Development of techniques in magnetic resonance and structural studies of the prion protein

    SciTech Connect

    Bitter, Hans-Marcus L.

    2000-07-01

    Magnetic resonance is the most powerful analytical tool used by chemists today. Its applications range from determining structures of large biomolecules to imaging of human brains. Nevertheless, magnetic resonance remains a relatively young field, in which many techniques are currently being developed that have broad applications. In this dissertation, two new techniques are presented, one that enables the determination of torsion angles in solid-state peptides and proteins, and another that involves imaging of heterogenous materials at ultra-low magnetic fields. In addition, structural studies of the prion protein via solid-state NMR are described. More specifically, work is presented in which the dependence of chemical shifts on local molecular structure is used to predict chemical shift tensors in solid-state peptides with theoretical ab initio surfaces. These predictions are then used to determine the backbone dihedral angles in peptides. This method utilizes the theoretical chemicalshift tensors and experimentally determined chemical-shift anisotropies (CSAs) to predict the backbone and side chain torsion angles in alanine, leucine, and valine residues. Additionally, structural studies of prion protein fragments are described in which conformationally-dependent chemical-shift measurements were made to gain insight into the structural differences between the various conformational states of the prion protein. These studies are of biological and pathological interest since conformational changes in the prion protein are believed to cause prion diseases. Finally, an ultra-low field magnetic resonance imaging technique is described that enables imaging and characterization of heterogeneous and porous media. The notion of imaging gases at ultra-low fields would appear to be very difficult due to the prohibitively low polarization and spin densities as well as the low sensitivities of conventional Faraday coil detectors. However, Chapter 5 describes how gas imaging

  6. Development of advanced magnetic resonance sensor for industrial applications. Final report

    SciTech Connect

    De Los Santos, A.

    1997-06-01

    Southwest Research Institute (SwRI) and various subcontractors, in a cooperative agreement with the DOE, have developed and tested an advanced magnetic resonance (MR) sensor for several industrial applications and made various market surveys. The original goal of the program was to develop an advanced moisture sensor to allow more precise and rapid control of drying processes so that energy and/or product would not be wasted. Over the course of the program, it was shown that energy savings were achievable but in many processes the return in investment did not justify the cost of a magnetic resonance sensor. However, in many processes, particularly chemical, petrochemical, paper and others, the return in investment can be very high as to easily justify the cost of a magnetic resonance sensor. In these industries, substantial improvements in product yield, quality, and efficiency in production can cause substantial energy savings and reductions in product wastage with substantial environmental effects. The initial applications selected for this program included measurement of corn gluten at three different points and corn germ at one point in an American Maize corn processing plant. During the initial phases (I and II) of this program, SwRI developed a prototype advanced moisture sensor utilizing NMR technology capable of accurately and reliably measuring moisture in industrial applications and tested the sensor in the laboratory under conditions simulating on-line products in the corn wet milling industry. The objective of Phase III was to test the prototype sensor in the plant environment to determine robustness, reliability and long term stability. Meeting these objectives would permit extended field testing to improve the statistical database used to calibrate the sensor and subject the sensor to true variations in operating conditions encountered in the process rather than those which could only be simulated in the laboratory.

  7. Development of a multilayered polymeric DNA biosensor using radio frequency technology with gold and magnetic nanoparticles.

    PubMed

    Yang, Cheng-Hao; Kuo, Long-Sheng; Chen, Ping-Hei; Yang, Chii-Rong; Tsai, Zuo-Min

    2012-01-15

    This study utilized the radio frequency (RF) technology to develop a multilayered polymeric DNA sensor with the help of gold and magnetic nanoparticles. The flexible polymeric materials, poly (p-xylylene) (Parylene) and polyethylene naphtholate (PEN), were used as substrates to replace the conventional rigid substrates such as glass and silicon wafers. The multilayered polymeric RF biosensor, including the two polymer layers and two copper transmission structure layers, was developed to reduce the total sensor size and further enhance the sensitivity of the biochip in the RF DNA detection. Thioglycolic acid (TGA) was used on the surface of the proposed biochip to form a thiolate-modified sensing surface for DNA hybridization. Gold nanoparticles (AuNPs) and magnetic nanoparticles (MNPs) were used to immobilize on the surface of the biosensor to enhance overall detection sensitivity. In addition to gold nanoparticles, the magnetic nanoparticles has been demonstrated the applicability for RF DNA detection. The performance of the proposed biosensor was evaluated by the shift of the center frequency of the RF biosensor because the electromagnetic characteristic of the biosensors can be altered by the immobilized multilayer nanoparticles on the biosensor. The experimental results show that the detection limit of the DNA concentration can reach as low as 10 pM, and the largest shift of the center frequency with triple-layer AuNPs and MNPs can approach 0.9 and 0.7 GHz, respectively. Such the achievement implies that the developed biosensor can offer an alternative inexpensive, disposable, and highly sensitive option for application in biomedicine diagnostic systems because the price and size of each biochip can be effectively reduced by using fully polymeric materials and multilayer-detecting structures. PMID:22093770

  8. Magnetic susceptibility and the spatial variability of heavy metals in soils developed on basalt

    NASA Astrophysics Data System (ADS)

    Cervi, Eduardo Cimino; da Costa, Antonio Carlos Saraiva; de Souza Junior, Ivan Granemann

    2014-12-01

    Topsoil magnetic susceptibility (κ) is a fast and convenient method used to detect potentially polluted areas by heavy metals. Topsoil measurements are carried out in situ with Bartington MS2D loop sensor, designed to measure the magnetic susceptibility of top 10 cm of soil and detect 90% of the total signal from a depth of 6 cm. However, soils developed on basalt are difficult to assess due to their large amounts of ferrimagnetic minerals. The aim of this study was evaluate the applicability of κ to discriminate anthropogenic/lithogenic environments characterized by different parent materials in the city of Maringá/Brazil. In this paper, topsoil susceptibility (κ) was measured in 66 urban soils using a Bartington MS2D loop sensor. To investigate the magnetic background levels, samples of a Rhodic Ferralsol profile were measured using a laboratory MS2B sensor. X-ray diffractometry (XRD) analysis was carried out to verify the mineralogical composition of the different lithology. Cu, Fe, Ni, Mn, Pb and Zn concentrations were measured in 29 topsoil samples. The κ values ranged from 316 × 10- 5 SI in a sandstone region to 6,945 × 10- 5 SI in soils developed on basalt. The χfd values of urban topsoil varied from 2% to 11.3%. Lower values of κ and χfd in the sandstone region indicated that the lithogenic contribution is of primary significance. Significant positive correlations between κ and Cu, Fe and Mn are related to the parent material, enriched in iron oxides, as verified by XRD. The background values (mean of 4,235 × 10- 8 m3 kg- 1) were higher in subsoil, suggesting the inexistence of anthropogenic pollution. The topsoil susceptibility was efficient for distinguish different lithogenic environments. Although anthropogenic pollution in soils developed on basalt is difficult to assess due to the high natural background, our results suggest that heavy metal contents are not related to the human activity.

  9. X-rays and magnetism.

    PubMed

    Fischer, Peter; Ohldag, Hendrik

    2015-09-01

    Magnetism is among the most active and attractive areas in modern solid state physics because of intriguing phenomena interesting to fundamental research and a manifold of technological applications. State-of-the-art synthesis of advanced magnetic materials, e.g. in hybrid structures paves the way to new functionalities. To characterize modern magnetic materials and the associated magnetic phenomena, polarized x-rays have emerged as unique probes due to their specific interaction with magnetic materials. A large variety of spectroscopic and microscopic techniques have been developed to quantify in an element, valence and site-sensitive way properties of ferro-, ferri-, and antiferromagnetic systems, such as spin and orbital moments, and to image nanoscale spin textures and their dynamics with sub-ns time and almost 10 nm spatial resolution. The enormous intensity of x-rays and their degree of coherence at next generation x-ray facilities will open the fsec time window to magnetic studies addressing fundamental time scales in magnetism with nanometer spatial resolution. This review will give an introduction into contemporary topics of nanoscale magnetic materials and provide an overview of analytical spectroscopy and microscopy tools based on x-ray dichroism effects. Selected examples of current research will demonstrate the potential and future directions of these techniques. PMID:26288956

  10. Development of a Gas Filled Magnet spectrometer within the FIPPS project

    NASA Astrophysics Data System (ADS)

    Chebboubi, A.; Kessedjian, G.; Faust, H.; Blanc, A.; Jentschel, M.; Köster, U.; Materna, T.; Méplan, O.; Sage, C.; Serot, O.

    2016-06-01

    The Fission Product Prompt γ -ray Spectrometer, FIPPS, is under development to enable prompt γ -ray spectroscopy correlated with fission fragment identification. This will open new possibilities in the study of fission and of nuclear structure of neutron rich nuclei. FIPPS will consist of an array of γ and neutron detectors coupled with a fission fragment filter. The chosen solution for the filter is a Gas Filled Magnet (GFM). Both experimental and modeling work was performed in order to extract the key parameters of such a device and design the future GFM of the FIPPS project. Experiments performed with a GFM behind the LOHENGRIN spectrometer demonstrated the capability of additional beam purification.

  11. Development of Rutherford-type cables for high field accelerator magnets at Fermilab

    SciTech Connect

    Andreev, N.; Barzi, E.; Borissov, E.; Elementi, L.; Kashikhin, V.S.; Lombardo, V.; Rusy, A.; Turrioni, D.; Yamada, R.; Zlobin, A.V.; /Fermilab

    2006-08-01

    Fermilab's cabling facility has been upgraded to a maximum capability of 42 strands. This facility is being used to study the effect of cabling on the performance of the various strands, and for the development and fabrication of cables in support of the ongoing magnet R&D programs. Rutherford cables of various geometries, packing factors, with and without a stainless steel core, were fabricated out of Cu alloys, NbTi, Nb{sub 3}Al, and various Nb{sub 3}Sn strands. The parameters of the upgraded cabling machine and results of cable R&D efforts at Fermilab are reported.

  12. Development of a Flat-plate Cryogenic Oscillating Heat Pipe for Improving HTS Magnet Cooling

    NASA Astrophysics Data System (ADS)

    Natsume, K.; Mito, T.; Yanagi, N.; Tamura, H.

    A new method of including cryogenic oscillating heat pipes (OHPs) in the HTS coil windings as a thermal transport device has been studied. In this work, two type of OHPs are tested in low temperature. Employed working fluids are H2, Ne, N2. We have attained high performance thermal property using a bent-pipe cryogenic OHP as a prototype. Obtained effective conductivities have reached to 46000 W/m K. Then a flat-plate cryogenic OHP has been developed, that is suitable for imbedding in magnet windings. Preliminary experiments have been conducted and the result has been promising.

  13. Development and field trial of a FBG-based magnetic sensor for large hydrogenerators

    NASA Astrophysics Data System (ADS)

    Fracarolli, João. P. V.; Rosolem, João. B.; Tomiyama, Elias K.; Floridia, Claudio; Penze, Rivael S.; Peres, Rodrigo; Dini, Danilo C.; Hortencio, Claudio A.; Dilli, Paulo I. G.; da Silva, Erlon V.; dos Santos, Marcéu. C.; Fruett, Fabiano

    2016-05-01

    We propose a passive optical sensor for online magnetic field monitoring in large hydrogenerators, based on FBG (Fiber Bragg Grating) technology and a magnestostrictive material (Terfenol-D). The objective of this sensor is to detect faults in the rotor windings due to inter turn short-circuits. This device is packaged in a novel rod-shaped enclosure, allowing it to be easily installed on the ventilation ducts of the stator of the machine. This sensor was developed and tested in laboratory and it has been evaluated in a field test on a 200 MVA, 60 poles hydrogenerator.

  14. Self-attracting walk on heterogeneous networks

    NASA Astrophysics Data System (ADS)

    Kim, Kanghun; Kyoung, Jaegu; Lee, D.-S.

    2016-05-01

    Understanding human mobility in cyberspace becomes increasingly important in this information era. While human mobility, memory-dependent and subdiffusive, is well understood in Euclidean space, it remains elusive in random heterogeneous networks like the World Wide Web. Here we study the diffusion characteristics of self-attracting walks, in which a walker is more likely to move to the locations visited previously than to unvisited ones, on scale-free networks. Under strong attraction, the number of distinct visited nodes grows linearly in time with larger coefficients in more heterogeneous networks. More interestingly, crossovers to sublinear growths occur in strongly heterogeneous networks. To understand these phenomena, we investigate the characteristic volumes and topology of the cluster of visited nodes and find that the reinforced attraction to hubs results in expediting exploration first but delaying later, as characterized by the scaling exponents that we derive. Our findings and analysis method can be useful for understanding various diffusion processes mediated by human.

  15. Evolution of 'pollinator'- attracting signals in fungi.

    PubMed

    Schiestl, Florian P; Steinebrunner, Fabrizio; Schulz, Claudia; von Reuss, Stephan; Francke, Wittko; Weymuth, Christophe; Leuchtmann, Adrian

    2006-09-22

    Fungi produce a plethora of secondary metabolites yet their biological significance is often little understood. Some compounds show well-known antibiotic properties, others may serve as volatile signals for the attraction of insects that act as vectors of spores or gametes. Our investigations in an outcrossing, self-incompatible fungus show that a fungus-produced volatile compound with fungitoxic activities is also responsible for the attraction of specific insects that transfer gametes. We argue that insect attraction using this compound is likely to have evolved from its primary function of defence--as has been suggested for floral scent in the angiosperms. We, thus, propose that similar yet convergent evolutionary pathways have lead to interspecific communication signals in both fungi and plants. PMID:17148414

  16. Recognition bias and the physical attractiveness stereotype.

    PubMed

    Rohner, Jean-Christophe; Rasmussen, Anders

    2012-06-01

    Previous studies have found a recognition bias for information consistent with the physical attractiveness stereotype (PAS), in which participants believe that they remember that attractive individuals have positive qualities and that unattractive individuals have negative qualities, regardless of what information actually occurred. The purpose of this research was to examine whether recognition bias for PAS congruent information is replicable and invariant across a variety of conditions (i.e. generalizable). The effects of nine different moderator variables were examined in two experiments. With a few exceptions, the effect of PAS congruence on recognition bias was independent of the moderator variables. The results suggest that the tendency to believe that one remembers information consistent with the physical attractiveness stereotype is a robust phenomenon. PMID:22416805

  17. Self-attracting walk on heterogeneous networks.

    PubMed

    Kim, Kanghun; Kyoung, Jaegu; Lee, D-S

    2016-05-01

    Understanding human mobility in cyberspace becomes increasingly important in this information era. While human mobility, memory-dependent and subdiffusive, is well understood in Euclidean space, it remains elusive in random heterogeneous networks like the World Wide Web. Here we study the diffusion characteristics of self-attracting walks, in which a walker is more likely to move to the locations visited previously than to unvisited ones, on scale-free networks. Under strong attraction, the number of distinct visited nodes grows linearly in time with larger coefficients in more heterogeneous networks. More interestingly, crossovers to sublinear growths occur in strongly heterogeneous networks. To understand these phenomena, we investigate the characteristic volumes and topology of the cluster of visited nodes and find that the reinforced attraction to hubs results in expediting exploration first but delaying later, as characterized by the scaling exponents that we derive. Our findings and analysis method can be useful for understanding various diffusion processes mediated by human. PMID:27300913

  18. Motivated behavioral outcomes affect ratings of attractiveness.

    PubMed

    Bernard, Larry C; Hardy, David J

    2014-12-01

    A relatively new theory of motivation posits that purposeful human behavior may be partly explained by multidimensional individual differences "traits of action" (motives). Its 15 motives can be characterized according to their purpose: individual integrity, competitiveness, and cooperativeness. Existing evidence supports the model on which the motives are based and the reliability and validity of strategies to assess them. This experiment tested whether the hypothetical results of consistent, motivated cooperative and competitive behavior could affect ratings of attractiveness. Male and female participants (N = 98; M age = 18.8, SD = 1.4) were shown 24 opposite-sex facial photos ranging in attractiveness. The photos were paired with one of three conditions representing theoretical outcomes that would result from low, control, and high levels of cooperative and competitive motives. As predicted, outcome descriptions representing high motive strength of six motives statistically significantly affected ratings of attractiveness. This result was independent of sex of participant and consistent with the theory. PMID:25457092

  19. Dynamo Activity in Strongly Magnetized Accretion Disks

    NASA Astrophysics Data System (ADS)

    Salvesen, Greg; Simon, Jacob B.; Armitage, Philip J.; Begelman, Mitchell C.

    2016-01-01

    Strongly magnetized accretion disks around black holes have many attractive features that may explain the enigmatic behavior observed from X-ray binaries. The physics and structure of these disks are governed by a dynamo-like mechanism, which channels the accretion power liberated by the magnetorotational instability into an ordered toroidal magnetic field. To study dynamo activity, we performed three-dimensional, stratified, isothermal, ideal magnetohydrodynamic shearing box simulations. In our simulations, the strength of this self-sustained toroidal magnetic field depends on the net vertical magnetic flux we impose, which allows us to study weak-to-strong magnetization regimes. We find that the entire disk develops into a magnetic pressure-dominated state for a sufficiently strong net vertical magnetic flux. Over the two orders of magnitude in net vertical magnetic flux that we consider, the effective α-viscosity parameter scales as a power-law. We quantify dynamo properties of toroidal magnetic flux production and its buoyant escape as a function of disk magnetization. Finally, we compare our simulations to an analytic model for the vertical structure of strongly magnetized disks applicable to the high/soft state of X-ray binaries.

  20. Malaria Parasites Produce Volatile Mosquito Attractants

    PubMed Central

    Kelly, Megan; Su, Chih-Ying; Schaber, Chad; Crowley, Jan R.; Hsu, Fong-Fu; Carlson, John R.

    2015-01-01

    ABSTRACT The malaria parasite Plasmodium falciparum contains a nonphotosynthetic plastid organelle that possesses plant-like metabolic pathways. Plants use the plastidial isoprenoid biosynthesis pathway to produce volatile odorants, known as terpenes. In this work, we describe the volatile chemical profile of cultured malaria parasites. Among the identified compounds are several plant-like terpenes and terpene derivatives, including known mosquito attractants. We establish the molecular identity of the odorant receptors of the malaria mosquito vector Anopheles gambiae, which responds to these compounds. The malaria parasite produces volatile signals that are recognized by mosquitoes and may thereby mediate host attraction and facilitate transmission. PMID:25805727