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Sample records for accelerator laboratory pal

  1. The Brookhaven National Laboratory Accelerator Test Facility

    SciTech Connect

    Batchelor, K.

    1992-01-01

    The Brookhaven National Laboratory Accelerator Test Facility comprises a 50 MeV traveling wave electron linear accelerator utilizing a high gradient, photo-excited, raidofrequency electron gun as an injector and an experimental area for study of new acceleration methods or advanced radiation sources using free electron lasers. Early operation of the linear accelerator system including calculated and measured beam parameters are presented together with the experimental program for accelerator physics and free electron laser studies.

  2. The Brookhaven National Laboratory Accelerator Test Facility

    SciTech Connect

    Batchelor, K.

    1992-09-01

    The Brookhaven National Laboratory Accelerator Test Facility comprises a 50 MeV traveling wave electron linear accelerator utilizing a high gradient, photo-excited, raidofrequency electron gun as an injector and an experimental area for study of new acceleration methods or advanced radiation sources using free electron lasers. Early operation of the linear accelerator system including calculated and measured beam parameters are presented together with the experimental program for accelerator physics and free electron laser studies.

  3. Vehicle Systems Integration Laboratory Accelerates Powertrain Development

    ScienceCinema

    None

    2016-07-12

    ORNL's Vehicle Systems Integration (VSI) Laboratory accelerates the pace of powertrain development by performing prototype research and characterization of advanced systems and hardware components. The VSI Lab is capable of accommodating a range of platforms from advanced light-duty vehicles to hybridized Class 8 powertrains with the goals of improving overall system efficiency and reducing emissions.

  4. Numerical and laboratory simulations of auroral acceleration

    SciTech Connect

    Gunell, H.; De Keyser, J.; Mann, I.

    2013-10-15

    The existence of parallel electric fields is an essential ingredient of auroral physics, leading to the acceleration of particles that give rise to the auroral displays. An auroral flux tube is modelled using electrostatic Vlasov simulations, and the results are compared to simulations of a proposed laboratory device that is meant for studies of the plasma physical processes that occur on auroral field lines. The hot magnetospheric plasma is represented by a gas discharge plasma source in the laboratory device, and the cold plasma mimicking the ionospheric plasma is generated by a Q-machine source. In both systems, double layers form with plasma density gradients concentrated on their high potential sides. The systems differ regarding the properties of ion acoustic waves that are heavily damped in the magnetosphere, where the ion population is hot, but weakly damped in the laboratory, where the discharge ions are cold. Ion waves are excited by the ion beam that is created by acceleration in the double layer in both systems. The efficiency of this beam-plasma interaction depends on the acceleration voltage. For voltages where the interaction is less efficient, the laboratory experiment is more space-like.

  5. Observation of particle acceleration in laboratory magnetosphere

    SciTech Connect

    Kawazura, Y.; Yoshida, Z.; Nishiura, M.; Saitoh, H.; Yano, Y.; Nogami, T.; Sato, N.; Yamasaki, M.; Kashyap, A.; Mushiake, T.

    2015-11-15

    The self-organization of magnetospheric plasma is brought about by inward diffusion of magnetized particles. Not only creating a density gradient toward the center of a dipole magnetic field, the inward diffusion also accelerates particles and provides a planetary radiation belt with high energy particles. Here, we report the first experimental observation of a “laboratory radiation belt” created in the ring trap 1 device. By spectroscopic measurement, we found an appreciable anisotropy in the ion temperature, proving the betatron acceleration mechanism which heats particles in the perpendicular direction with respect to the magnetic field when particles move inward. The energy balance model, including the heating mechanism, explains the observed ion temperature profile.

  6. Accelerator Mass Spectrometry in Laboratory Nuclear Astrophysics

    NASA Astrophysics Data System (ADS)

    Nusair, O.; Bauder, W.; Gyürky, G.; Paul, M.; Collon, P.; Fülöp, Zs; Greene, J.; Kinoshita, N.; Palchan, T.; Pardo, R.; Rehm, K. E.; Scott, R.; Vondrasek, R.

    2016-01-01

    The extreme sensitivity and discrimination power of accelerator mass spectrometry (AMS) allows for the search and the detection of rare nuclides either in natural samples or produced in the laboratory. At Argonne National Laboratory, we are developing an AMS setup aimed in particular at the detection of medium and heavy nuclides, relying on the high ion energy achievable with the ATLAS superconducting linear accelerator and on gas-filled magnet isobaric separation. The setup was recently used for the detection of the 146Sm p-process nuclide and for a new determination of the 146Sm half-life (68.7 My). AMS plays an important role in the measurement of stellar nuclear reaction cross sections by the activation method, extending thus the technique to the study of production of long-lived radionuclides. Preliminary measurements of the 147Sm(γ,n)146Sm are described. A measurement of the 142Nd(α,γ)146Sm and 142Nd(α,n)145Sm reactions is in preparation. A new laser-ablation method for the feeding of the Electron Cyclotron Resonance (ECR) ion source is described.

  7. Radiation shielding design of the PAL-XFEL

    NASA Astrophysics Data System (ADS)

    Jung, Nam-Suk; Lee, Hee-Seock; Oh, Joo-Hee; Kim, Bum-Jong

    2015-02-01

    The construction of the Pohang Accelerator Laboratory X-ray Free Electron Laser (PAL-XFEL) started in 2011. The PAL-XFEL is designed to generate X-rays using 10 GeV, 0.2 nC electron beams. For the radiation shielding design, a beam-loss scenario suitable for the PAL-XFEL should be established. The beam-loss scenario was determined and categorized as normal or accidental. The electron beam will be shut down automatically when accidental beam-loss occurs. Using this scenario, the thickness of the accelerator and undulator tunnel of the PAL-XFEL was calculated by using the SHIELD11 code, and complicated tunnel structures such as maze entrances, sliding doors, trenches, sleeves, and ducts, were determined under the assumption of a thick iron target by using the FLUKA code. A detailed design of the main beam dump was established, and shielding structures at the front end for suppression of the radiation dose at the experimental area under the accidental beam-loss scenario were considered. The muon production was estimated by using the FLUKA code.

  8. PAL: Positional Astronomy Library

    NASA Astrophysics Data System (ADS)

    Jenness, T.; Berry, D. S.

    2016-06-01

    The PAL library is a partial re-implementation of Pat Wallace's popular SLALIB library written in C using a Gnu GPL license and layered on top of the IAU's SOFA library (or the BSD-licensed ERFA) where appropriate. PAL attempts to stick to the SLA C API where possible.

  9. The target laboratory of the Pelletron Accelerator's facilities

    SciTech Connect

    Ueta, Nobuko; Pereira Engel, Wanda Gabriel

    2013-05-06

    A short report on the activities developed in the Target Laboratory, since 1970, will be presented. Basic target laboratory facilities were provided to produce the necessary nuclear targets as well as the ion beam stripper foils. Vacuum evaporation units, a roller, a press and an analytical balance were installed in the Oscar Sala building. A brief historical report will be presented in commemoration of the 40{sup th} year of the Pelletron Accelerator.

  10. Reproduction of natural corrosion by accelerated laboratory testing methods

    SciTech Connect

    Luo, J.S.; Wronkiewicz, D.J.; Mazer, J.J.; Bates, J.K.

    1996-05-01

    Various laboratory corrosion tests have been developed to study the behavior of glass waste forms under conditions similar to those expected in an engineered repository. The data generated by laboratory experiments are useful for understanding corrosion mechanisms and for developing chemical models to predict the long-term behavior of glass. However, it is challenging to demonstrate that these test methods produce results that can be directly related to projecting the behavior of glass waste forms over time periods of thousands of years. One method to build confidence in the applicability of the test methods is to study the natural processes that have been taking place over very long periods in environments similar to those of the repository. In this paper, we discuss whether accelerated testing methods alter the fundamental mechanisms of glass corrosion by comparing the alteration patterns that occur in naturally altered glasses with those that occur in accelerated laboratory environments. This comparison is done by (1) describing the alteration of glasses reacted in nature over long periods of time and in accelerated laboratory environments and (2) establishing the reaction kinetics of naturally altered glass and laboratory reacted glass waste forms.

  11. PALS in mathematics classroom

    NASA Astrophysics Data System (ADS)

    Karim, Mariathy; Mohammed, Siti Rosiah; Bosli, Fazillah; Abdullah, Nurhidayah Masni; Mahat, Aishah; Dasman, Anisah; Tarmuji, Nor Habibah; Ahmad, Salimah

    2014-07-01

    Peer Asissted Learning Strategies (PALS) is a type of cooperative learning where high and low performing students are gathered into a small group to achieve common goals and improve individual's understanding. The objectives of this study are to investigate students' perception about PALS and to identify optional methods to improve the technique for future implementation. The Mengubah Destini Anak Bangsa (MDAB) students selected for this study were from pre diploma level of studies in the Pre-Commerce Program. Cluster sampling was used to randomly select eight out of ten groups. Ninety nine students in the selected group became the respondents. Three groups were identified as Experimental Group (EG) and another five groups as Control Group (CG). A Diagnostic Test was given to all ten groups of students during the first week of class. Students in EG were given instructions using PALS. At the end of the semester, questionnaires were distributed to students in EG and analyzed. This study revealed that students had positive responses to PALS and a few suggestions from students to improve PALS were obtained.

  12. Modeling laser-plasma acceleration in the laboratory frame

    SciTech Connect

    2011-01-01

    A simulation of laser-plasma acceleration in the laboratory frame. Both the laser and the wakefield buckets must be resolved over the entire domain of the plasma, requiring many cells and many time steps. While researchers often use a simulation window that moves with the pulse, this reduces only the multitude of cells, not the multitude of time steps. For an artistic impression of how to solve the simulation by using the boosted-frame method, watch the video "Modeling laser-plasma acceleration in the wakefield frame."

  13. Development of new S-band SLED for PAL-XFEL Linac

    NASA Astrophysics Data System (ADS)

    Joo, Youngdo; Park, Yongjung; Heo, Hoon; Heo, Jinyul; Park, Sung-Soo; Kim, Sang-Hee; Kim, Kwang-Hoon; Kang, Heung-Sik; Lee, Heung-Soo; Noh, Sungju; Oh, Kyoungmin

    2017-01-01

    In order to achieve beam acceleration to the beam energy of 10 GeV at the end of its 716 m-long linear accelerator (Linac), the Pohang Accelerator Laboratory X-ray Free Electron Laser (PAL-XFEL) is going to operate the Stanford Linear Accelerator Energy Doubler (SLED) at the maximum klystron output peak power of 80 MW, with a pulse length of 4 μs, and at a repetition rate of 60 Hz. The original SLED that had been used in Pohang Light Source-II (PLS-II) can no longer sustain such a high-power operation because excessive radiation caused by RF breakdown has been frequently detected even at the lower klystron peak power during the PLS-II operation. Therefore, a new SLED is designed by modifying both the 3-dB power hybrid and the waveguide-cavity coupling structure of the original SLED where the excessive radiation has been mainly detected. The finite-difference time-domain (FDTD) simulation in the CST Microwave Studio shows that the new SLED has a peak electric field and a surface current lower than those of the original SLED at the same level of the RF input peak power, which would secure stable high-power operation. All of the 42 SLEDs in the PAL-XFEL Linac are newly fabricated and installed. During the RF conditioning of the PAL-XFEL Linac, no significant vacuum and radiation issue was found in the new SLEDs. Finally, the accelerated electron beam energy of 10 GeV obtained at the end of the PAL-XFEL Linac verified that the RF performance of the new SLED is stable.

  14. Absolute gravity acceleration measurement in atomic sensor laboratories

    NASA Astrophysics Data System (ADS)

    de Angelis, M.; Greco, F.; Pistorio, A.; Poli, N.; Prevedelli, M.; Saccorotti, G.; Sorrentino, F.; Tino, G. M.

    2012-03-01

    This paper reports the results from the accurate measurement of the acceleration of gravity g taken at two separate premises in the Polo Scientifico of the Florence University (Italy). In these laboratories, two separate experiments aiming at measuring the Newtonian constant and testing the measurement of forces with high spatial resolution are in progress. Both experiments require an independent knowledge on the local value of g. Gravity measurements were conducted using an FG5 absolute gravimeter, and accompanied by seismic recordings for evaluating the noise condition at the site. The absolute accelerations of gravity at the two laboratories are ( 980 492 160.6 ± 4.0) μGal and ( 980 492 048.3 ± 3.0) μGal for the European Laboratory for Non-Linear Spectroscopy (LENS) and Dipartimento di Fisica e Astronomia, respectively. Other than for the two referenced experiments, the data here presented will serve as a benchmark for any future study requiring an accurate knowledge of the absolute value of the acceleration of gravity in the study region.

  15. Low Energy Accelerator Laboratory Technical Area 53, Los Alamos National Laboratory. Environmental assessment

    SciTech Connect

    1995-04-01

    This Environmental Assessment (EA) analyzes the potential environmental impacts that would be expected to occur if the Department of Energy (DOE) were to construct and operate a small research and development laboratory building at Technical Area (TA) 53 at the Los Alamos National Laboratory (LANL), Los Alamos, New Mexico. DOE proposes to construct a small building to be called the Low Energy Accelerator Laboratory (LEAL), at a previously cleared, bladed, and leveled quarter-acre site next to other facilities housing linear accelerator research activities at TA-53. Operations proposed for LEAL would consist of bench-scale research, development, and testing of the initial section of linear particle accelerators. This initial section consists of various components that are collectively called an injector system. The anticipated life span of the proposed development program would be about 15 years.

  16. Post-accelerator issues at the IsoSpin Laboratory

    SciTech Connect

    Chattopadhyay, S.; Nitschke, J.M.

    1994-05-01

    The workshop on ``Post-Accelerator Issues at the Isospin Laboratory`` was held at the Lawrence Berkeley Laboratory from October 27--29, 1993. It was sponsored by the Center for Beam Physics in the Accelerator and Fusion Research Division and the ISL Studies Group in the Nuclear Science Division. About forty scientists from around the world participated vigorously in this two and a half day workshop, (c.f. Agenda, Appendix D). Following various invited review talks from leading practitioners in the field on the first day, the workshop focussed around two working groups: (1) the Ion Source and Separators working group and (2) the Radio Frequency Quadrupoles and Linacs working group. The workshop closed with the two working groups summarizing and outlining the tasks for the future. This report documents the proceedings of the workshop and includes the invited review talks, the two summary talks from the working groups and individual contributions from the participants. It is a complete assemblage of state-of-the-art thinking on ion sources, low-{beta}, low(q/A) accelerating structures, e.g. linacs and RFQS, isobar separators, phase-space matching, cyclotrons, etc., as relevant to radioactive beam facilities and the IsoSpin Laboratory. We regret to say that while the fascinating topic of superconducting low-velocity accelerator structure was covered by Dr. K. Shepard during the workshop, we can only reproduce the copies of the transparencies of his talk in the Appendix, since no written manuscript was available at the time of publication of this report. The individual report have been catologed separately elsewhere.

  17. Felsenkeller shallow-underground accelerator laboratory for nuclear astrophysics

    NASA Astrophysics Data System (ADS)

    Bemmerer, D.; Cowan, T. E.; Gohl, S.; Ilgner, C.; Junghans, A. R.; Reinhardt, T. P.; Rimarzig, B.; Reinicke, S.; Röder, M.; Schmidt, K.; Schwengner, R.; Stöckel, K.; Szücs, T.; Takács, M.; Wagner, A.; Wagner, L.; Zuber, K.

    2015-05-01

    Favored by the low background in underground laboratories, low-background accelerator-based experiments are an important tool to study nuclear reactions involving stable charged particles. This technique has been used for many years with great success at the 0.4 MV LUNA accelerator in the Gran Sasso laboratory in Italy, proteced from cosmic rays by 1400 m of rock. However, the nuclear reactions of helium and carbon burning and the neutron source reactions for the astrophysical s-process require higher beam energies than those available at LUNA. Also the study of solar fusion reactions necessitates new data at higher energies. As a result, in the present NuPECC long range plan for nuclear physics in Europe, the installation of one or more higher-energy underground accelerators is strongly recommended. An intercomparison exercise has been carried out using the same HPGe detector in a typical nuclear astrophysics setup at several sites, including the Dresden Felsenkeller underground laboratory. It was found that its rock overburden of 45m rock, together with an active veto against the remaining muon flux, reduces the background to a level that is similar to the deep underground scenario. Based on this finding, a used 5 MV pelletron tandem with 250 μA upcharge current and external sputter ion source has been obtained and transported to Dresden. Work on an additional radio-frequency ion source on the high voltage terminal is underway. The project is now fully funded. The installation of the accelerator in the Felsenkeller is expected for the near future. The status of the project and the planned access possibilities for external users will be reported.

  18. Construction status of CXI beamline at PAL-XFEL

    NASA Astrophysics Data System (ADS)

    Park, Jaehyun; Nam, Ki-Hyun; Kim, Sangsoo; Kim, Bongsoo; Ko, In Soo; Cho, Moohyun

    2015-05-01

    Pohang Accelerator Laboratory X-ray Free Electron Laser (PAL-XFEL) is a research facility currently under construction. It will provide ultra-bright (assuming 1 X 1012 photons/pulse at 12.4 keV) and ultra-short (10-60 femtosecond) X-ray pulses. The CXI (Coherent X-ray Imaging) end-station, which will be constructed for hard X-ray beamline at the PAL-XFEL, is designed to deliver brilliant hard x-rays (2-20 keV) and to measure diffraction signals with forward scattering geometry, mainly. Not only will it offer imaging studies of biological, chemical and physical samples by the "diffract-before-destroy" technique, but will also be helpful in high field hard x-ray physics and material science. The scientific programs are currently aimed at serial femtosecond crystallography (SFX) for macromolecular systems and coherent diffraction imaging for bio specimens and nano structures etc. In this paper, we describe the details of the beamline layout, X-ray focusing optics (Kirkpatrick-Baez mirror and Beryllium CRLs) and sample delivery system (liquid jet/LCP sample injector, fixed target system) that will be installed at the CXI beamline.

  19. The cyclotron laboratory and the RFQ accelerator in Bern

    SciTech Connect

    Braccini, S.; Ereditato, A.; Kreslo, I.; Nirkko, M.; Weber, M.; Scampoli, P.; Bremen, K. von

    2013-07-18

    Two proton accelerators have been recently put in operation in Bern: an 18 MeV cyclotron and a 2 MeV RFQ linac. The commercial IBA 18/18 cyclotron, equipped with a specifically conceived 6 m long external beam line ending in a separate bunker, will provide beams for routine 18-F and other PET radioisotope production as well as for novel detector, radiation biophysics, radioprotection, radiochemistry and radiopharmacy developments. The accelerator is embedded into a complex building hosting two physics laboratories and four Good Manufacturing Practice (GMP) laboratories. This project is the result of a successful collaboration between the Inselspital, the University of Bern and private investors, aiming at the constitution of a combined medical and research centre able to provide the most cutting-edge technologies in medical imaging and cancer radiation therapy. The cyclotron is complemented by the RFQ with the primary goals of elemental analysis via Particle Induced Gamma Emission (PIGE), and the detection of potentially dangerous materials with high nitrogen content using the Gamma-Resonant Nuclear Absorption (GRNA) technique. In this context, beam instrumentation devices have been developed, in particular an innovative beam profile monitor based on doped silica fibres and a setup for emittance measurements using the pepper-pot technique. On this basis, the establishment of a proton therapy centre on the campus of the Inselspital is in the phase of advanced study.

  20. The cyclotron laboratory and the RFQ accelerator in Bern

    NASA Astrophysics Data System (ADS)

    Braccini, S.; Ereditato, A.; Kreslo, I.; Nirkko, M.; Scampoli, P.; von Bremen, K.; Weber, M.

    2013-07-01

    Two proton accelerators have been recently put in operation in Bern: an 18 MeV cyclotron and a 2 MeV RFQ linac. The commercial IBA 18/18 cyclotron, equipped with a specifically conceived 6 m long external beam line ending in a separate bunker, will provide beams for routine 18-F and other PET radioisotope production as well as for novel detector, radiation biophysics, radioprotection, radiochemistry and radiopharmacy developments. The accelerator is embedded into a complex building hosting two physics laboratories and four Good Manufacturing Practice (GMP) laboratories. This project is the result of a successful collaboration between the Inselspital, the University of Bern and private investors, aiming at the constitution of a combined medical and research centre able to provide the most cutting-edge technologies in medical imaging and cancer radiation therapy. The cyclotron is complemented by the RFQ with the primary goals of elemental analysis via Particle Induced Gamma Emission (PIGE), and the detection of potentially dangerous materials with high nitrogen content using the Gamma-Resonant Nuclear Absorption (GRNA) technique. In this context, beam instrumentation devices have been developed, in particular an innovative beam profile monitor based on doped silica fibres and a setup for emittance measurements using the pepper-pot technique. On this basis, the establishment of a proton therapy centre on the campus of the Inselspital is in the phase of advanced study.

  1. PREFACE: Acceleration and radiation generation in space and laboratory plasmas

    NASA Astrophysics Data System (ADS)

    Bingham, R.; Katsouleas, T.; Dawson, J. M.; Stenflo, L.

    1994-01-01

    Sixty-six leading researchers from ten nations gathered in the Homeric village of Kardamyli, on the southern coast of mainland Greece, from August 29-September 4, 1993 for the International Workshop on Acceleration and Radiation Generation in Space and Laboratory Plasmas. This Special Issue represents a cross-section of the presentations made at and the research stimulated by that meeting. According to the Iliad, King Agamemnon used Kardamyli as a dowry offering in order to draw a sulking Achilles into the Trojan War. 3000 years later, Kardamyli is no less seductive. Its remoteness and tranquility made it an ideal venue for promoting the free exchange of ideas between various disciplines that do not normally interact. Through invited presen tations, informal poster discussions and working group sessions, the Workshop brought together leaders from the laboratory and space/astrophysics communities working on common problems of acceleration and radiation generation in plasmas. It was clear from the presentation and discussion sessions that there is a great deal of common ground between these disciplines which is not at first obvious due to the differing terminologies and types of observations available to each community. All of the papers in this Special Issue highlight the role collective plasma processes play in accelerating particles or generating radiation. Some are state-of-the-art presentations of the latest research in a single discipline, while others investi gate the applicability of known laboratory mechanisms to explain observations in natural plasmas. Notable among the latter are the papers by Marshall et al. on kHz radiation in the magnetosphere ; Barletta et al. on collective acceleration in solar flares; and by Dendy et al. on ion cyclotron emission. The papers in this Issue are organized as follows: In Section 1 are four general papers by Dawson, Galeev, Bingham et al. and Mon which serves as an introduction to the physical mechanisms of acceleration

  2. Laboratory selection for an accelerated mosquito sexual development rate

    PubMed Central

    2011-01-01

    Background Separating males and females at the early adult stage did not ensure the virginity of females of Anopheles arabiensis (Dongola laboratory strain), whereas two years earlier this method had been successful. In most mosquito species, newly emerged males and females are not able to mate successfully. For anopheline species, a period of 24 h post-emergence is generally required for the completion of sexual maturation, which in males includes a 180° rotation of the genitalia. In this study, the possibility of an unusually shortened sexual maturity period in the laboratory-reared colony was investigated. Methods The effect of two different sex-separation methods on the virginity of females was tested: females separated as pupae or less than 16 h post-emergence were mated with males subjected to various doses of radiation. T-tests were performed to compare the two sex-separation methods. The rate of genitalia rotation was compared for laboratory-reared and wild males collected as pupae in Dongola, Sudan, and analysed by Z-tests. Spermatheca dissections were performed on females mated with laboratory-reared males to determine their insemination status. Results When the sex-separation was performed when adults were less than 16 h post-emergence, expected sterility was never reached for females mated with radio-sterilized males. Expected sterility was accomplished only when sexes were separated at the pupal stage. Observation of genitalia rotation showed that some males from the laboratory strain Dongola were able to successfully mate only 11 h after emergence and 42% of the males had already completed rotation. A small proportion of the same age females were inseminated. Wild males showed a much slower genitalia rotation rate. At 17 h post-emergence, 96% of the laboratory-reared males had completed genitalia rotation whereas none of the wild males had. Conclusion This colony has been cultured in the laboratory for over one hundred generations, and now has

  3. Streamlining workflow and automation to accelerate laboratory scale protein production.

    PubMed

    Konczal, Jennifer; Gray, Christopher H

    2017-03-19

    Protein production facilities are often required to produce diverse arrays of proteins for demanding methodologies including crystallography, NMR, ITC and other reagent intensive techniques. It is common for these teams to find themselves a bottleneck in the pipeline of ambitious projects. This pressure to deliver has resulted in the evolution of many novel methods to increase capacity and throughput at all stages in the pipeline for generation of recombinant proteins. This review aims to describe current and emerging options to accelerate the success of protein production in Escherichia coli. We emphasize technologies that have been evaluated and implemented in our laboratory, including innovative molecular biology and expression vectors, small-scale expression screening strategies and the automation of parallel and multidimensional chromatography.

  4. Environmental Survey preliminary report, Fermi National Accelerator Laboratory, Batavia, Illinois

    SciTech Connect

    Not Available

    1988-10-01

    This report presents the preliminary findings from the first phase of the Environmental Survey of the US Department of Energy (DOE) Fermi National Accelerator Laboratory (Fermilab), conducted September 14 through 25, 1987. The Survey is being conducted by an interdisciplinary team of environmental specialists led and managed by the Office of Environment, Safety and Health's Office of Environmental Audit. Individual participants for the Survey team are being supplied by a private contractor. The objective of the Survey is to identify environmental problems and areas of environmental risk associated with Fermilab. The Survey covers all environmental media and all areas of environmental regulation. It is being performed in accordance with the DOE Environmental Survey Manual. This phase of the Survey involves the review of existing site environmental data, observations of the operations performed at Fermilab, and interviews with site personnel. 110 refs., 26 figs., 41 tabs.

  5. The Bowling Pin Pal Reunion

    ERIC Educational Resources Information Center

    Berman, Michele Heide

    2007-01-01

    Seeing different retrospectives, which show the progression of works by an artist during their lifetime, inspired the author to organize a retrospective showcasing a progression of student works. In November of 2005, the author and her visual art colleagues celebrated the first Bowling Pin Pal Reunion. For 30 years, the bowling pin pals have been…

  6. Tiger Team Assessment of the Fermi National Accelerator Laboratory

    SciTech Connect

    Not Available

    1992-06-01

    This draft report documents the Tiger Team Assessment of the Fermi National Accelerator Laboratory (Fermilab) located in Batavia, Illinois. Fermilab is a program-dedicated national laboratory managed by the Universities Research Association, Inc. (URA) for the US Department of Energy (DOE). The Tiger Team Assessment was conducted from May 11 to June 8, 1992, under the auspices of DOE's Office of Special Projects (OSP) under the Office of the Assistant Secretary for Environment, Safety and Health (EH). The assessment was comprehensive, encompassing environmental, safety and health (ES H), and quality assurance (QA) disciplines; site remediation; facilities management; and waste management operations. Compliance with applicable Federal , State of Illinois, and local regulations; applicable DOE Orders; best management practices; and internal Fermilab requirements was addressed. In addition, an evaluation of the effectiveness of DOE and Fermilab management of the ES H/QA and self-assessment programs was conducted. The Fermilab Tiger Team Assessment is part a larger, comprehensive DOE Tiger Team Independent Assessment Program planned for DOE facilities. The objective of the initiative is to provide the Secretary of Energy with information on the compliance status of DOE facilities with regard to ES H requirements, root causes for noncompliance, adequacy of DOE and contractor ES H management programs, response actions to address the identified problem areas, and DOE-wide ES H compliance trends and root causes.

  7. Tiger Team Assessment of the Fermi National Accelerator Laboratory

    SciTech Connect

    Not Available

    1992-06-01

    This draft report documents the Tiger Team Assessment of the Fermi National Accelerator Laboratory (Fermilab) located in Batavia, Illinois. Fermilab is a program-dedicated national laboratory managed by the Universities Research Association, Inc. (URA) for the US Department of Energy (DOE). The Tiger Team Assessment was conducted from May 11 to June 8, 1992, under the auspices of DOE`s Office of Special Projects (OSP) under the Office of the Assistant Secretary for Environment, Safety and Health (EH). The assessment was comprehensive, encompassing environmental, safety and health (ES&H), and quality assurance (QA) disciplines; site remediation; facilities management; and waste management operations. Compliance with applicable Federal , State of Illinois, and local regulations; applicable DOE Orders; best management practices; and internal Fermilab requirements was addressed. In addition, an evaluation of the effectiveness of DOE and Fermilab management of the ES&H/QA and self-assessment programs was conducted. The Fermilab Tiger Team Assessment is part a larger, comprehensive DOE Tiger Team Independent Assessment Program planned for DOE facilities. The objective of the initiative is to provide the Secretary of Energy with information on the compliance status of DOE facilities with regard to ES&H requirements, root causes for noncompliance, adequacy of DOE and contractor ES&H management programs, response actions to address the identified problem areas, and DOE-wide ES&H compliance trends and root causes.

  8. Use of the BINP HLS to measure vertical changes in the locations of the building and ground at the PAL-XFEL

    NASA Astrophysics Data System (ADS)

    Choi, Hyo-Jin; Seo, Kwang-Won; Gil, Kye-Hwan; Kim, Seung-Hwan; Kang, Heung-Sik

    2016-09-01

    The Pohang Accelerator Laboratory's X-ray free-electron laser (PAL-XFEL), a 4 th generation light source, is currently being installed and will be completed by December 2015 so that users can be supported beginning in 2016. The PAL-XFEL equipment must continuously maintain the bunch-tobunch beam parameters (60 Hz, Energy: 10 GeV, Charge: 200 pC, Bunch Length: 60 fs, Emittance X/Y: 0.481/0.256 mm rad) in order to supply stable photons with the energy and flux appropriate for tests by beamline users. To this end, the PAL-XFEL equipment has to be kept precisely aligned (Linear Accelerator: +/- 100 μm, Undulator: +/- 50 μm). As a part of the process for installing the PAL-XFEL, a GPS-using surface geodetic network is being constructed for precise equipment measurement and alignment, and the installation of a tunnel measurement network inside the buildings is in the preparation stage; additionally, the fiducialization of major equipment is underway. After the PAL-XFEL equipment is optimized and aligned, if the ground and the buildings go through vertical changes during operation, misalignment (and tilt) of the equipment, including various magnets and RF structures, will cause errors in the electron beam's trajectory, which will lead to changes to the beam parameters. For continuous and systemic measurement of vertical changes in the buildings and monitoring of ground sinking and uplifting, the Budker Institute of Nuclear Physics (BINP) Ultrasonic-type Hydrostatic Levelling System (HLS) is to be installed and operated in all sections of the PAL-XFEL for the linear accelerator, the insertion device (undulator) and the beamline. This study will introduce the operation principle, design concept, and advantages (self-calibration) of the HLS and will outline its installation plan and operation plan.

  9. Laboratory test of Newton's second law for small accelerations.

    PubMed

    Gundlach, J H; Schlamminger, S; Spitzer, C D; Choi, K-Y; Woodahl, B A; Coy, J J; Fischbach, E

    2007-04-13

    We have tested the proportionality of force and acceleration in Newton's second law, F=ma, in the limit of small forces and accelerations. Our tests reach well below the acceleration scales relevant to understanding several current astrophysical puzzles such as the flatness of galactic rotation curves, the Pioneer anomaly, and the Hubble acceleration. We find good agreement with Newton's second law at accelerations as small as 5 x 10(-14) m/s(2).

  10. Laboratory Test of Newton's Second Law for Small Accelerations

    SciTech Connect

    Gundlach, J. H.; Schlamminger, S.; Spitzer, C. D.; Choi, K.-Y.; Woodahl, B. A.; Coy, J. J.; Fischbach, E.

    2007-04-13

    We have tested the proportionality of force and acceleration in Newton's second law, F=ma, in the limit of small forces and accelerations. Our tests reach well below the acceleration scales relevant to understanding several current astrophysical puzzles such as the flatness of galactic rotation curves, the Pioneer anomaly, and the Hubble acceleration. We find good agreement with Newton's second law at accelerations as small as 5x10{sup -14} m/s{sup 2}.

  11. Laboratory Test of Newton's Second Law for Small Accelerations

    NASA Astrophysics Data System (ADS)

    Woodahl, Brian; Gundlach, Jens; Schlamminger, Stephan; Spitzer, Chris; Choi, Ki; Coy, Jen; Fischbach, Ephraim

    2009-10-01

    We have tested the proportionality of force and acceleration in Newton's second law, F=ma, in the limit of small forces and accelerations. Our tests reach well below the acceleration scales relevant to understanding several current astrophysical puzzles such as the flatness of galactic rotation curves, the Pioneer anomaly, and the Hubble acceleration. We find good agreement with Newton's second law at accelerations as small as 5 x 10-14 m/s^2.

  12. Laboratory Test of Newton's Second Law for Small Accelerations

    NASA Astrophysics Data System (ADS)

    Gundlach, J. H.; Schlamminger, S.; Spitzer, C. D.; Choi, K.-Y.; Woodahl, B. A.; Coy, J. J.; Fischbach, E.

    2007-04-01

    We have tested the proportionality of force and acceleration in Newton’s second law, F=ma, in the limit of small forces and accelerations. Our tests reach well below the acceleration scales relevant to understanding several current astrophysical puzzles such as the flatness of galactic rotation curves, the Pioneer anomaly, and the Hubble acceleration. We find good agreement with Newton’s second law at accelerations as small as 5×10-14m/s2.

  13. Panel discussion on laboratory accelerator programs: present and future

    SciTech Connect

    Richter, B.

    1986-09-01

    The present SLAC accelerator program is summarized briefly, and the future of electron-positron colliders is discussed. Present activities discussed include the PEP storage ring, the SPEAR storage ring, the Linear Accelerator, and the SLAC Linear Collider (SLC) project. Future prospects include a larger scale linear collider. The stability requirements on acceleration are briefly discussed. (LEW)

  14. PAL(TM) 2.0 Human Anatomy Software Tool Use in Community College Traditional and Online Anatomy Laboratory Classes: Student-Perceived Learning Benefits

    ERIC Educational Resources Information Center

    Kuyatt, Brian Lee

    2012-01-01

    Human anatomy courses, with laboratory, are curricular requirements in graduate medical, undergraduate nursing, and all allied health science programs. Anatomy laboratory courses engage students in hands-on activities, including human cadaver or mammalian dissection, supported by photos from textbooks, detailed plastic models or human anatomical…

  15. Laboratory Test of Newton's Second Law for Small Accelerations

    NASA Astrophysics Data System (ADS)

    Woodahl, Brian; Gundlach, Jens; Schlamminger, Stephan; Spitzer, Chris; Choi, Ki; Coy, Jennifer; Fischbach, Ephraim

    2007-05-01

    We have tested the proportionality of force and acceleration in Newton's second law, F=ma, in the limit of small forces and accelerations. Our tests reach well below the acceleration scales relevant to understanding several current astrophysical puzzles such as the flatness of galactic rotation curves, the Pioneer anomaly, and the Hubble acceleration. We find good agreement with Newton's second law at accelerations as small as 5 x 10-14 m/s^2. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.OSS07.P1.15

  16. The Scanning Electron Microscope As An Accelerator For The Undergraduate Advanced Physics Laboratory

    SciTech Connect

    Peterson, Randolph S.; Berggren, Karl K.; Mondol, Mark

    2011-06-01

    Few universities or colleges have an accelerator for use with advanced physics laboratories, but many of these institutions have a scanning electron microscope (SEM) on site, often in the biology department. As an accelerator for the undergraduate, advanced physics laboratory, the SEM is an excellent substitute for an ion accelerator. Although there are no nuclear physics experiments that can be performed with a typical 30 kV SEM, there is an opportunity for experimental work on accelerator physics, atomic physics, electron-solid interactions, and the basics of modern e-beam lithography.

  17. Individually designed PALs vs. power optimized PALs adaptation comparison.

    PubMed

    Muždalo, Nataša Vujko; Mihelčič, Matjaž

    2015-03-01

    The practice shows that in everyday life we encounter ever-growing demand for better visual acuity at all viewing distances. The presbyopic population needs correction to far, near and intermediate distance with different dioptric powers. PAL lenses seem to be a comfortable solution. The object of the present study is the analysis of the factors determining adaptation to progressive addition lenses (PAL) of the first-time users. Only novice test persons were chosen in order to avoid the bias of previously worn particular lens design. For optimal results with this type of lens, several individual parameters must be considered: correct refraction, precise ocular and facial measures, and proper mounting of lenses into the frame. Nevertheless, first time wearers encounter various difficulties in the process of adapting to this type of glasses and adaptation time differs greatly between individual users. The question that arises is how much the individual parameters really affect the ease of adaptation and comfort when wearing progressive glasses. To clarify this, in the present study, the individual PAL lenses--Rodenstock's Impression FreeSign (with inclusion of all parameters related to the user's eye and spectacle frame: prescription, pupillary distance, fitting height, back vertex distance, pantoscopic angle and curvature of the frame) were compared to power optimized PAL--Rodenstock's Multigressiv MyView (respecting only prescription power and pupillary distance). Adaptation process was monitored over a period of four weeks. The collected results represent scores of user's subjective impressions, where the users themselves rated their adaptation to new progressive glasses and the degree of subjective visual impression. The results show that adaptation time to fully individually fit PAL is easier and quickly. The information obtained from users is valuable in everyday optometry practice because along with the manufacturer's specifications, the user's experience can

  18. Correlation between mechanical and chemical degradation after outdoor and accelerated laboratory aging for multilayer photovoltaic backsheets

    NASA Astrophysics Data System (ADS)

    Lin, Chiao-Chi; Lyu, Yadong; Yu, Li-Chieh; Gu, Xiaohong

    2016-09-01

    Channel cracking fragmentation testing and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy were utilized to study mechanical and chemical degradation of a multilayered backsheet after outdoor and accelerated laboratory aging. A model sample of commercial PPE backsheet, namely polyethylene terephthalate/polyethylene terephthalate/ethylene vinyl acetate (PET/PET/EVA) was investigated. Outdoor aging was performed in Gaithersburg, Maryland, USA for up to 510 days, and complementary accelerated laboratory aging was conducted on the NIST (National Institute of Standards and Technology) SPHERE (Simulated Photodegradation via High Energy Radiant Exposure). Fracture energy, mode I stress intensity factor and film strength were analyzed using an analytical model based on channel cracking fragmentation testing results. The correlation between mechanical and chemical degradation was discussed for both outdoor and accelerated laboratory aging. The results of this work provide preliminary understanding on failure mechanism of backsheets after weathering, laying the groundwork for linking outdoor and indoor accelerated laboratory testing for multilayer photovoltaic backsheets.

  19. Numerical Investigation and Experimental Reproduction of Fermi Acceleration in Laboratory Scale

    NASA Astrophysics Data System (ADS)

    Zhou, M.; Zhai, C.

    2015-12-01

    Fermi acceleration is widely accepted as the mechanism to explain power law of cosmic ray spectrum. Now this mechanism has been developed to first order Fermi acceleration and second order Fermi acceleration. In first order Fermi acceleration, also known as diffusive shock acceleration, particles are confined around the shock through scattering and accelerated by repeatedly crossing shock front. In second order Fermi acceleration, particles gain energy through statistical collisions with interstellar clouds. In this proposed work, we plan to carefully study these two kinds of acceleration numerically and experimentally. We first consider a single relativistic particle and investigate how it gains energy in Fermi-Ulam model and shock wave acceleration model respectively. We investigate collective behavior of particles with different kinds of wall-oscillation functions and try to find an optimal one in terms of efficiency of acceleration. Then, we plan to go further and consider a group of particles statistically, during which we borrow the correct generalization of Maxwell's velocity distribution in special relativity and compare the results with those in cases where we simply use Maxwell-Boltzmann distribution. To this end, we try to provide a scheme to build an accelerator applying both laser technology and mirror effect in Laboratory to reproduce Fermi acceleration, which might be a promising source to obtain high energy particles and further study the mechanism of cosmic rays acceleration.

  20. Pen Pals: Practicing Problem Solving

    ERIC Educational Resources Information Center

    Lampe, Kristen A.; Uselmann, Linda

    2008-01-01

    This article describes a semester-long pen-pal project in which preservice teachers composed mathematical problems and the middle school students worked for solutions. The college students assessed the solution and the middle school students provided feedback regarding the problem itself. (Contains 6 figures.)

  1. Fermi National Accelerator Laboratory Annual Program Review 1993

    SciTech Connect

    1993-01-01

    This book is submitted as a written adjunct to the 1993 Annual DOE High Energy Physics Program Review of Fermilab, scheduled for March 31-April 3. In it are described the functions and activities of the various Laboratory Divisions and Sections plus statements of plans and goals for the coming year. The Review Committee, as this goes to press, consists of·

  2. Fermi National Accelerator Laboratory Annual Program Review 1991

    SciTech Connect

    Appel, Jeffrey A.; Jovanovic, Drasko; Pordes, Stephen

    1991-01-01

    This book is submitted as a written adjunct to the Annual DOE High Energy Physics Program Review of Fermilab, scheduled this year for April 10-12, 1991. In it are described the functions and activities of the various Laboratory areas plus statements of plans and goals for the coming year.

  3. Fermi National Accelerator Laboratory Annual Program Review 2000

    SciTech Connect

    2000-03-01

    This book is submitted as one written part of the 2000 Annual DOE High Energy Physics Program Review of Fermilab, scheduled March 22-24, 2000. In it are Director's Overview, some experimental highlights, discussions of several projects, and descriptions of the functions and activities of the four laboratory divisions. This book should be read in conjunction with the 2000 Fermilab Workbook and the review presentations (both in formal sessions and at the poster session).

  4. Chemical depth profiling of photovoltaic backsheets after accelerated laboratory weathering

    NASA Astrophysics Data System (ADS)

    Lin, Chiao-Chi; Krommenhoek, Peter J.; Watson, Stephanie S.; Gu, Xiaohong

    2014-10-01

    Polymeric multilayer backsheets provide protection for the backside of photovoltaic (PV) module from the damage of moisture and ultraviolet (UV). Due to the nature of multilayer films, certain material property characterization of a backsheet could only be studied by examining its cross-section parallel to the thickness direction of the film. In this study, commercial PPE (polyethylene terephthalate (PET)/PET/ethylene vinyl acetate (EVA)) backsheet films were aged on the NIST (National Institute of Standards and Technology) SPHERE (Simulated Photodegradation via High Energy Radiant Exposure) with UV irradiance at 170 W/m2 (300 nm to 400 nm) under accelerated weathering conditions of 85°C and two relative humidity (R.H.) levels of 5% (low) and 60% (high). Cryo-microtomy was used to obtain cross-sectional PPE samples with a flat surface parallel to the thickness direction, and chemical depth profiling of multilayers was conducted by Raman microscopic mapping. Atomic force microscopy with peak force tapping mode was used complementarily for cross-sectional imaging. The results revealed that the PPE backsheet films were comprised of five main layers, including pigmented-PET, core PET, inner EVA, pigmented-EVA and outer EVA, along with their interfacial regions and two adhesive layers. UV and moisture degradation on the outer pigmented PET layer was clearly observed; while the damage on the core PET layer was less significance, indicating that the outer pigmented PET layer effectively reduced the damage from UV. In high R.H. exposure, both adhesive layers were severely deteriorated. It was found that the EVA layers were susceptible to moisture at elevated temperature, especially for the pigmented-EVA. Based on the results of accelerated weathering, this depth profiling study brings new understanding to the mechanisms of failure observed in polymeric multilayer backsheets during field exposure.

  5. Observation of Ion Acceleration and Heating during Collisionless Magnetic Reconnection in a Laboratory Plasma

    SciTech Connect

    Yoo, Jongsoo; Yamada, Masaaki; Ji, Hantao; Myers, Clayton E.

    2012-12-10

    The ion dynamics in a collisionless magnetic reconnection layer are studied in a laboratory plasma. The measured in-plane plasma potential profile, which is established by electrons accelerated around the electron diffusion region, shows a saddle-shaped structure that is wider and deeper towards the outflow direction. This potential structure ballistically accelerates ions near the separatrices toward the outflow direction. Ions are heated as they travel into the high pressure downstream region.

  6. AmeriFlux US-IB2 Fermi National Accelerator Laboratory- Batavia (Prairie site)

    DOE Data Explorer

    Matamala, Roser [Argonne National Laboratory

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-IB2 Fermi National Accelerator Laboratory- Batavia (Prairie site). Site Description - Two eddy correlation systems are installed at Fermi National Accelerator Laboratory: one on a restored prairie (established October 2004) and one on a corn/soybean rotation agricultural field (established in July 2005). The prairie site had been farmed for more than 100 years, but was converted to prairie in 1989. April annual to bi-annual prescribed burns have taken place from 1994 - 2007.

  7. AmeriFlux US-IB1 Fermi National Accelerator Laboratory- Batavia (Agricultural site)

    SciTech Connect

    Matamala, Roser

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-IB1 Fermi National Accelerator Laboratory- Batavia (Agricultural site). Site Description - Two eddy correlation systems are installed at Fermi National Accelerator Laboratory: one on a restored prairie (established October 2004) and one on a corn/soybean rotation agricultural field (established in July 2005). The prairie site had been farmed for more than 100 years, but was converted to prairie in 1989. The agricultural site has likely been farmed for more than 100 years, but the first documented instance of agricultural activity dates back to a picture taken in 1952.

  8. ACCELERATION OF LOS ALAMOS NATIONAL LABORATORY TRANSURANIC WASTE DISPOSITION

    SciTech Connect

    O'LEARY, GERALD A.

    2007-01-04

    One of Los Alamos National Laboratory's (LANL's) most significant risks is the site's inventory of transuranic waste retrievably stored above and below-ground in Technical Area (TA) 54 Area G, particularly the dispersible high-activity waste stored above-ground in deteriorating facilities. The high activity waste represents approximately 50% (by activity) of the total 292,000 PE-Ci inventory remaining to be disposed. The transuramic waste inventory includes contact-handled and remote-handled waste packaged in drums, boxes, and oversized containers which are retrievably stored both above and below-ground. Although currently managed as transuranic waste, some of the inventory is low-level waste that can be disposed onsite or at approved offsite facilities. Dispositioning the transuranic waste inventory requires retrieval of the containers from above and below-ground storage, examination and repackaging or remediation as necessary, characterization, certification and loading for shipment to the Waste Isolation Pilot Plant in Carlsbad New Mexico, all in accordance with well-defined requirements and controls. Although operations are established to process and characterize the lower-activity contact-handled transuranic waste containers, LAN L does not currently have the capability to repack high activity contact-handled transuranic waste containers (> 56 PE-Ci) or to process oversized containers with activity levels over 0.52 PE-Ci. Operational issues and compliance requirements have resulted in less than optimal processing capabilities for lower activity contact-handled transuranic waste containers, limiting preparation and reducing dependability of shipments to the Waste Isolation Pilot Plant. Since becoming the Los Alamos National Laboratory contract in June 2006, Los Alamos National Security (LANS) L.L.C. has developed a comprehensive, integrated plan to effectively and efficiently disposition the transuranic waste inventory, working in concert with the Department of

  9. Technical Design Report for the FACET-II Project at SLAC National Accelerator Laboratory

    SciTech Connect

    None, None

    2016-08-26

    The discovery of the Higgs boson, a subatomic particle whose field is responsible for endowing all other particles with mass, is one of the major discoveries of the last decade. To unlock the mysteries of the subatomic world, physicists use the worlds’ most powerful microscopes – particle accelerators. The resolving power of these microscopes is proportional to the energy of the beams they produce. Since their inception nearly 80 years ago, the energy reach of accelerators has grown exponentially due to continued breakthroughs in accelerator physics and engineering. The highest energy beams in the world are currently at the 27km circumference Large Hadron Collider (LHC) in Europe. Although it is a monument to human engineering, scientists are approaching a practical limit to the size and cost of such collider facilities. Innovation is essential for continued progress. Electrons can “surf” on waves of plasma – a hot gas of charged particles – gaining very high energies in very short distances. This approach, called plasma wakefield acceleration, has the potential to dramatically shrink the size and cost of particle accelerators. Research at the SLAC National Accelerator Laboratory has demonstrated that plasmas can provide 1,000 times the acceleration in a given distance compared with current technologies. Developing revolutionary and more efficient acceleration techniques that allow for an affordable high-energy collider has been the focus of FACET, a National User Facility at SLAC.

  10. PAL-XFEL laser heater commissioning

    NASA Astrophysics Data System (ADS)

    Lee, JaeHyun; Han, Jang-Hui; Lee, Sojeong; Hong, Juho; Kim, Chul Hoon; Min, Chang Ki; Ko, In Soo

    2017-01-01

    X-ray free electron lasers (XFELs) require electron beams with a peak current of several kA and a transverse emittance below 1 mm mrad. The uncorrelated energy spread of the beam should be as small as 0.01% of the beam energy. A photoinjector generates an electron beam satisfying the requirements, however the uncorrelated energy spread of the beam is too small, about one keV. A beam with such a low uncorrelated energy spread may suffer from the longitudinal microbunching instability when the beam is accelerated and compressed through a linear accelerator. A laser heater system in the injector minimizes the microbunching instability growth by controlling the uncorrelated energy spread of the beam. In this paper, we introduce the PAL-XFEL laser heater system and the commissioning result. The laser heating effects depending on the undulator gap, infrared laser pulse energy and laser beam size are studied. Experimental studies on the laser heating depending on the relative spatial position between the infrared laser and electron beam are discussed in detail.

  11. PROVISIONAL ADVISORY LEVELS (PALs) FOR PHOSGENE (CG)

    SciTech Connect

    Glass-Mattie, Dana F; McClanahan, Mark; Koller, Loren; Adeshina, Femi; Ross, Robert Hord

    2009-01-01

    The PAL protocol was applied to estimate inhalation exposure limits for phosgene (CG). Data on humans are limited to occupational exposures or accounts from the use of phosgene as a chemical warfare agent in WWI. Animal studies with phosgene show a steep dose-response curve for pulmonary edema and mortality with little species variability in effects. Although immediately upon exposure lacrimation and upper respiratory irritation can occur, the main effect in the target organ, a progressive pulmonary edema, occurs after a latency period of 1-24 hours. PAL estimates were approved by the Expert Consultation Panel for Provisional Advisory Levels in May 2007. Exposure limits for oral exposure to CG are not developed due to insufficient data. PAL estimates for inhalation exposure to CG are presented: The 24-hour PAL values for severity levels 1, 2, and 3 are 0.0017, 0.0033 and 0.022 ppm, respectively. The 30-day PAL values are 0.0006 and 0.0012 ppm for the PAL 1 and 2 values, respectively. These 30-day inhalation values were also accepted as the 90-day and 2-year PAL 1 and 2 values. Data were not available for deriving 30-day, 90-day and 2-year PAL 3 values.

  12. Evaluation of raw acceleration sedentary thresholds in children and adults.

    PubMed

    Hildebrand, Maria; Hansen, Bjørge H; van Hees, Vincent T; Ekelund, Ulf

    2016-11-22

    The aim was to develop sedentary (sitting/lying) thresholds from hip and wrist worn raw tri-axial acceleration data from the ActiGraph and GENEActiv, and to examine the agreement between free-living time spent below these thresholds with sedentary time estimated by the activPAL. Sixty children and adults wore an ActiGraph and GENEActiv on the hip and wrist while performing six structured activities, before wearing the monitors, in addition to an activPAL, for 24 h. Receiver operating characteristic (ROC) curves were used to determine sedentary thresholds based on activities in the laboratory. Agreement between developed sedentary thresholds during free-living and activPAL were assessed by Bland-Altman plots and by calculating sensitivity and specificity. Using laboratory data and ROC-curves showed similar classification accuracy for wrist and hip thresholds (Area under the curve = 0.84-0.92). Greatest sensitivity (97-98%) and specificity (74-78%) were observed for the wrist thresholds, with no large differences between brands. During free-living, Bland-Altman plots showed large mean individual biases and 95% limits of agreement compared with activPAL, with smallest difference for the ActiGraph wrist threshold in children (+30 min, P = 0.3). Sensitivity and specificity for the developed thresholds during free-living were low for both age groups and for wrist (Sensitivity, 68-88%, Specificity, 46-59%) and hip placements (Sensitivity, 89-97%, Specificity, 26-34%). Laboratory derived sedentary thresholds generally overestimate free-living sedentary time compared with activPAL. Wrist thresholds appear to perform better than hip thresholds for estimating free-living sedentary time in children and adults relative to activPAL, however, specificity for all the developed thresholds are low.

  13. On the ions acceleration via collisionless magnetic reconnection in laboratory plasmas

    NASA Astrophysics Data System (ADS)

    Cazzola, E.; Curreli, D.; Markidis, S.; Lapenta, G.

    2016-11-01

    This work presents an analysis of the ion outflow from magnetic reconnection throughout fully kinetic simulations with typical laboratory plasma values. A symmetric initial configuration for the density and magnetic field is considered across the current sheet. After analyzing the behavior of a set of nine simulations with a reduced mass ratio and with a permuted value of three initial electron temperatures and magnetic field intensity, the best ion acceleration scenario is further studied with a realistic mass ratio in terms of the ion dynamics and energy budget. Interestingly, a series of shock wave structures are observed in the outflow, resembling the shock discontinuities found in recent magnetohydrodynamic simulations. An analysis of the ion outflow at several distances from the reconnection point is presented, in light of possible laboratory applications. The analysis suggests that magnetic reconnection could be used as a tool for plasma acceleration, with applications ranging from electric propulsion to production of ion thermal beams.

  14. Collisionless shocks and particle acceleration in laser-driven laboratory plasmas

    NASA Astrophysics Data System (ADS)

    Fiuza, Frederico

    2012-10-01

    Collisionless shocks are pervasive in space and astrophysical plasmas, from the Earth's bow shock to Gamma Ray Bursters; however, the microphysics underlying shock formation and particle acceleration in these distant sites is not yet fully understood. Mimicking these extreme conditions in laboratory is a grand challenge that would allow for a better understanding of the physical processes involved. Using ab initio multi-dimensional particle-in-cell simulations, shock formation and particle acceleration are investigated for realistic laboratory conditions associated with the interaction of intense lasers with high-energy-density plasmas. Weibel-instability-mediated shocks are shown to be driven by the interaction of an ultraintense laser with overcritical plasmas. In this piston regime, the laser generates a relativistic flow that is Weibel unstable. The strong Weibel magnetic fields deflect the incoming flow, compressing it, and forming a shock. The resulting shock structure is consistent with previous simulations of relativistic astrophysical shocks, demonstrating for the first time the possibility of recreating these structures in laboratory. As the laser intensity is decreased and near-critical density plasmas are used, electron heating dominates over radiation pressure and electrostatic shocks can be formed. The electric field associated with the shock front can reflect ions from the background accelerating them to high energies. It is shown that high quality 200 MeV proton beams, required for tumor therapy, can be generated by using an exponentially decaying plasma profile to control competing accelerating fields. These results pave the way for the experimental exploration of space and astrophysical relevant shocks and particle acceleration with current laser systems.

  15. Doubling Beam Intensity Unlocks Rare Opportunities for Discovery at Fermi National Accelerator Laboratory

    SciTech Connect

    Segui, Jennifer A.

    2014-05-01

    Particle accelerators such as the Booster synchrotron at the Fermi National Accelerator Laboratory (FNAL) produce high-intensity proton beams for particle physics experiments that can ultimately reveal the secrets of the universe. High-intensity proton beams are required by experiments at the “intensity frontier” of particle physics research, where the availability of more particles improves the chances of observing extremely rare physical processes. In addition to their central role in particle physics experiments, particle accelerators have found widespread use in industrial, nuclear, environmental, and medical applications. RF cavities are essential components of particle accelerators that, depending on the design, can perform multiple functions, including bunching, focusing, decelerating, and accelerating a beam of charged particles. Engineers are working to model the RF cavities required for upgrading the 40-year old Booster synchrotron. It is a rather complicated process to refurbish, test, and qualify the upgraded RF cavities to sustain an increased repetition rate of the RF field required to produce proton beams at double the current intensity. Both multiphysics simulation and physical measurements are used to evaluate the RF, thermal, and mechanical properties of the Booster RF cavities.

  16. The Dresden Felsenkeller shallow-underground accelerator laboratory for nuclear astrophysics - Status and first physics program

    SciTech Connect

    Ilgner, Ch.

    2015-07-01

    Favored by the low background in underground laboratories, low-background accelerator-based experiments are an important tool to study nuclear reactions involving stable charged particles. This technique has been used for many years with great success at the 0.4 MV LUNA accelerator in the Gran Sasso laboratory in Italy, protected from cosmic rays by 1400 m of rock. However, the nuclear reactions of helium and carbon burning and the neutron source reactions for the astrophysical s-process require higher beam energies than those available at LUNA. Also the study of solar fusion reactions necessitates new data at higher energies. As a result, in the present NuPECC long range plan for nuclear physics in Europe, the installation of one or more higher-energy underground accelerators is strongly recommended. An intercomparison exercise using the same High-Purity Ge detector at several sites has shown that, with a combination of 45 m rock overburden, as can be found in the Felsenkeller underground site in Dresden, and an active veto against the remaining muon flux, in a typical nuclear astrophysics setup a background level can be achieved that is similar to the deep underground scenario as in the Gran- Sasso underground laboratory, for instance. Recently, a muon background study and geodetic measurements were carried out by the REGARD group. It was estimated that the rock overburden at the place of the future ion accelerator is equivalent to 130 m of water. The maximum muon flux measured was 2.5 m{sup -2} sr{sup -1} s{sup -1}, in the direction of the tunnel entrance. Based on this finding, a used 5 MV pelletron tandem accelerator with 250 μA up-charge current and external sputter ion source has been obtained and transported to Dresden. Work on an additional radio-frequency ion source on the high voltage terminal is in progress and far advanced. The installation of the accelerator in the Felsenkeller is expected for the near future. The status of the project and the

  17. Preliminary Conceptual Design Report for the FACET-II Project at SLAC National Accelerator Laboratory

    SciTech Connect

    Hogan, Mark

    2016-04-22

    Plasma wakefield acceleration has the potential to dramatically shrink the size and cost of particle accelerators. Research at the SLAC National Accelerator Laboratory has demonstrated that plasmas can provide 1,000 times the acceleration in a given distance compared with current technologies. Developing revolutionary and more efficient acceleration techniques that allow for an affordable high-energy collider is the focus of FACET, a National User Facility at SLAC. The existing FACET National User Facility uses part of SLAC’s two-mile-long linear accelerator to generate high-density beams of electrons and positrons. FACET-II is a new test facility to develop advanced acceleration and coherent radiation techniques with high-energy electron and positron beams. It is the only facility in the world with high energy positron beams. FACET-II provides a major upgrade over current FACET capabilities and the breadth of the potential research program makes it truly unique. It will synergistically pursue accelerator science that is vital to the future of both advanced acceleration techniques for High Energy Physics, ultra-high brightness beams for Basic Energy Science, and novel radiation sources for a wide variety of applications. The design parameters for FACET-II are set by the requirements of the plasma wakefield experimental program. To drive the plasma wakefield requires a high peak current, in excess of 10kA. To reach this peak current, the electron and positron design bunch size is 10μ by 10μ transversely with a bunch length of 10μ. This is more than 200 times better than what has been achieved at the existing FACET. The beam energy is 10 GeV, set by the Linac length available and the repetition rate is up to 30 Hz. The FACET-II project is scheduled to be constructed in three major stages. Components of the project discussed in detail include the following: electron injector, bunch compressors and linac, the positron system, the Sector 20 sailboat and W chicanes

  18. An improved 8 GeV beam transport system for the Fermi National Accelerator Laboratory

    SciTech Connect

    Syphers, M.J.

    1987-06-01

    A new 8 GeV beam transport system between the Booster and Main Ring synchrotrons at the Fermi National Accelerator Laboratory is presented. The system was developed in an effort to improve the transverse phase space area occupied by the proton beam upon injection into the Main Ring accelerator. Problems with the original system are described and general methods of beamline design are formulated. Errors in the transverse properties of a beamline at the injection point of the second synchrotron and their effects on the region in transverse phase space occupied by a beam of particles are discussed. Results from the commissioning phase of the project are presented as well as measurements of the degree of phase space dilution generated by the transfer of 8 GeV protons from the Booster synchrotron to the Main Ring synchrotron.

  19. Wet Lab Accelerator: A Web-Based Application Democratizing Laboratory Automation for Synthetic Biology.

    PubMed

    Bates, Maxwell; Berliner, Aaron J; Lachoff, Joe; Jaschke, Paul R; Groban, Eli S

    2017-01-20

    Wet Lab Accelerator (WLA) is a cloud-based tool that allows a scientist to conduct biology via robotic control without the need for any programming knowledge. A drag and drop interface provides a convenient and user-friendly method of generating biological protocols. Graphically developed protocols are turned into programmatic instruction lists required to conduct experiments at the cloud laboratory Transcriptic. Prior to the development of WLA, biologists were required to write in a programming language called "Autoprotocol" in order to work with Transcriptic. WLA relies on a new abstraction layer we call "Omniprotocol" to convert the graphical experimental description into lower level Autoprotocol language, which then directs robots at Transcriptic. While WLA has only been tested at Transcriptic, the conversion of graphically laid out experimental steps into Autoprotocol is generic, allowing extension of WLA into other cloud laboratories in the future. WLA hopes to democratize biology by bringing automation to general biologists.

  20. MCNP Neutron Simulations: The Effectiveness of the University of Kentucky Accelerator Laboratory Pit

    NASA Astrophysics Data System (ADS)

    Jackson, Daniel; Nguyen, Thien An; Hicks, S. F.; Rice, Ben; Vanhoy, J. R.

    2015-10-01

    The design of the Van de Graaff Particle Accelerator complex at the University of Kentucky is marked by the unique addition of a pit in the main neutron scattering room underneath the neutron source and detection shielding assembly. This pit was constructed as a neutron trap in order to decrease the amount of neutron flux within the laboratory. Such a decrease of background neutron flux effectively reduces as much noise as possible in detection of neutrons scattering off of desired samples to be studied. This project uses the Monte-Carlo N-Particle Transport Code (MCNP) to model the structure of the accelerator complex, gas cell, and the detector's collimator and shielding apparatus to calculate the neutron flux in various sections of the laboratory. Simulations were completed with baseline runs of 107 neutrons of energies 4 MeV and 17 MeV, produced respectively by 3H(p,n)3He and 3H(d,n)4He source reactions. In addition, a comparison model of the complex with simply a floor and no pit was designed, and the respective neutron fluxes of both models were calculated and compared. The results of the simulations seem to affirm the validity of the pit design in significantly reducing the overall neutron flux throughout the accelerator complex, which could be used in future designs to increase the precision and reliability of data. This project was supported in part by the DOE NEUP Grant NU-12-KY-UK-0201-05 and the Donald A. Cowan Physics Institute at the University of Dallas.

  1. On the effect of accelerated winds on the wave growth through detailed laboratory measurements.

    NASA Astrophysics Data System (ADS)

    Ocampo-Torres, Francisco J.; Branger, Hubert; Osuna, Pedro; Hernández, Aldo

    2013-04-01

    The possible influence of accelerated winds on air-water momentum fluxes is being studied through detailed laboratory measurements in a large wind-wave flume. Wind stress over the water surface, waves and surface drift are measured in the 40m long wind-wave tank at IRPHE, Marseille. While momentum fluxes are estimated directly through the eddy correlation method in a station about the middle of the tank, they provide information corresponding to rather short non-dimensional fetch not previously reported. Wave evolution along the tank is determined through a series of wave gauges, and the wind-induced surface drift is obtained at one of the first measuring stations at the beginning of the tank. At each experimental run very low wind was on (about 1m/s) for a certain period and suddenly it was constantly accelerated to reach about 13 m/s (as well as 8 and 5 m/s during different runs) in about 15 sec to as long as 600 sec. The wind was kept constant at that high speed for 2 to 10 min, and then suddenly and constantly decelerate to 0. Data from the constant high winds provided us with reference equilibrium conditions for at least 3 different wind speed. We, nevertheless, focus in the recordings while wind was being constantly accelerated expecting some contribution to the understanding of gustiness, the implied wind wave growth and the onset of surface drift. Wind-wave growth is observed to lag behind the wind stress signal, and furthermore, a two regime wind stress is noticed, apparently well correlated with a) the incipient growth and appearance of the first waves and b) the arrival of waves from the up-wind section of the tank. Results of non-dimensional wave energy as a function of non-dimensional fetch represent an extension of at least 2 decades shorter non-dimensional fetch to the wave growth curves typically found in the literature. The linear tendency of wave growth compares very well only when wind is reaching its maximum, while during the accelerated wind

  2. Laboratory Measurements of Linear Electron Acceleration by Inertial Alfvén Waves

    NASA Astrophysics Data System (ADS)

    Schroeder, J. W. R.

    2015-11-01

    Alfvén waves occur in conjunction with a significant fraction of auroral electron acceleration. Inertial mode Alfvén waves (vA >vte) in the auroral magnetosphere (2 - 4RE) with perpendicular scales on the order of the electron skin depth (c /ωpe) have a parallel electric field that, according to theory, is capable of nonlinearly accelerating suprathermal electrons to auroral energies. Unfortunately, due to space-time ambiguities of rocket and satellite measurements, it has not yet been possible to fully verify how Alfvén waves contribute to the production of accelerated electrons. To overcome the limitations of in situ spacecraft data, laboratory experiments have been carried out using the Large Plasma Device (LaPD), an NSF/DOE user facility at UCLA. An Electron Cyclotron Absorption (ECA) diagnostic has been developed to record the suprathermal parallel electron distribution function with 0.1% precision. The diagnostic records the electron distribution while inertial Alfvén waves simultaneously propagate through the plasma. Recent measurements have isolated oscillations of suprathermal electrons at the Alfvén wave frequency. Despite complications from boundary effects and the finite size of the experiment, a linear kinetic model has been produced that describes the experimental results. To our knowledge this is the first quantitative agreement between the measured and modeled linear response of suprathermal electrons to an inertial Alfvén wave. This verification of the linear physics is a necessary step before the nonlinear acceleration process can be isolated in future experiments. Presently, nonlinear effects cannot be detected because of limited Alfvén wave amplitudes. Ongoing work is focused on designing a higher-power antenna capable of efficiently launching larger-amplitude Alfvén waves with tunable perpendicular wavenumber and developing a theoretical understanding of the nonlinear acceleration process in LaPD plasma conditions. This material is

  3. Mega-electron-volt ultrafast electron diffraction at SLAC National Accelerator Laboratory.

    PubMed

    Weathersby, S P; Brown, G; Centurion, M; Chase, T F; Coffee, R; Corbett, J; Eichner, J P; Frisch, J C; Fry, A R; Gühr, M; Hartmann, N; Hast, C; Hettel, R; Jobe, R K; Jongewaard, E N; Lewandowski, J R; Li, R K; Lindenberg, A M; Makasyuk, I; May, J E; McCormick, D; Nguyen, M N; Reid, A H; Shen, X; Sokolowski-Tinten, K; Vecchione, T; Vetter, S L; Wu, J; Yang, J; Dürr, H A; Wang, X J

    2015-07-01

    Ultrafast electron probes are powerful tools, complementary to x-ray free-electron lasers, used to study structural dynamics in material, chemical, and biological sciences. High brightness, relativistic electron beams with femtosecond pulse duration can resolve details of the dynamic processes on atomic time and length scales. SLAC National Accelerator Laboratory recently launched the Ultrafast Electron Diffraction (UED) and microscopy Initiative aiming at developing the next generation ultrafast electron scattering instruments. As the first stage of the Initiative, a mega-electron-volt (MeV) UED system has been constructed and commissioned to serve ultrafast science experiments and instrumentation development. The system operates at 120-Hz repetition rate with outstanding performance. In this paper, we report on the SLAC MeV UED system and its performance, including the reciprocal space resolution, temporal resolution, and machine stability.

  4. Annual Site Environmental Report: 2015 (ASER) for the SLAC National Accelerator Laboratory

    SciTech Connect

    Sabba, Dellilah

    2016-09-01

    This report, prepared by the SLAC National Accelerator Laboratory (SLAC) for the U.S. Department of Energy (DOE), SLAC Site Office (SSO), provides a comprehensive summary of the environmental program activities at SLAC for calendar year 2015. Annual Site Environmental Reports (ASERs) are prepared for all DOE sites with significant environmental activities, and distributed to relevant external regulatory agencies and other interested organizations or individuals. To the best of my knowledge, this report accurately summarizes the results of the 2015 environmental monitoring, compliance, and restoration programs at SLAC. This assurance can be made based on SSO and SLAC review of the ASER, and quality assurance protocols applied to monitoring and data analyses at SLAC.

  5. Mega-electron-volt ultrafast electron diffraction at SLAC National Accelerator Laboratory

    SciTech Connect

    Weathersby, S. P.; Brown, G.; Chase, T. F.; Coffee, R.; Corbett, J.; Eichner, J. P.; Frisch, J. C.; Fry, A. R.; Gühr, M.; Hartmann, N.; Hast, C.; Hettel, R.; Jobe, R. K.; Jongewaard, E. N.; Lewandowski, J. R.; Li, R. K. Lindenberg, A. M.; Makasyuk, I.; May, J. E.; McCormick, D.; and others

    2015-07-15

    Ultrafast electron probes are powerful tools, complementary to x-ray free-electron lasers, used to study structural dynamics in material, chemical, and biological sciences. High brightness, relativistic electron beams with femtosecond pulse duration can resolve details of the dynamic processes on atomic time and length scales. SLAC National Accelerator Laboratory recently launched the Ultrafast Electron Diffraction (UED) and microscopy Initiative aiming at developing the next generation ultrafast electron scattering instruments. As the first stage of the Initiative, a mega-electron-volt (MeV) UED system has been constructed and commissioned to serve ultrafast science experiments and instrumentation development. The system operates at 120-Hz repetition rate with outstanding performance. In this paper, we report on the SLAC MeV UED system and its performance, including the reciprocal space resolution, temporal resolution, and machine stability.

  6. Mega-electron-volt ultrafast electron diffraction at SLAC National Accelerator Laboratory

    SciTech Connect

    Weathersby, S. P.; Brown, G.; Centurion, M.; Chase, T. F.; Coffee, R.; Corbett, J.; Eichner, J. P.; Frisch, J. C.; Fry, A. R.; Gühr, M.; Hartmann, N.; Hast, C.; Hettel, R.; Jobe, R. K.; Jongewaard, E. N.; Lewandowski, J. R.; Li, R. K.; Lindenberg, A. M.; Makasyuk, I.; May, J. E.; McCormick, D.; Nguyen, M. N.; Reid, A. H.; Shen, X.; Sokolowski-Tinten, K.; Vecchione, T.; Vetter, S. L.; Wu, J.; Yang, J.; Dürr, H. A.; Wang, X. J.

    2015-07-01

    Ultrafast electron probes are powerful tools, complementary to x-ray free-electron lasers, used to study structural dynamics in material, chemical, and biological sciences. High brightness, relativistic electron beams with femtosecond pulse duration can resolve details of the dynamic processes on atomic time and length scales. SLAC National Accelerator Laboratory recently launched the Ultrafast Electron Diffraction (UED) and microscopy Initiative aiming at developing the next generation ultrafast electron scattering instruments. As the first stage of the Initiative, a mega-electron-volt (MeV) UED system has been constructed and commissioned to serve ultrafast science experiments and instrumentation development. The system operates at 120-Hz repetition rate with outstanding performance. In this paper, we report on the SLAC MeV UED system and its performance, including the reciprocal space resolution, temporal resolution, and machine stability.

  7. Proposed low-level radioactive waste handling building at Fermi National Accelerator Laboratory, Batavia, Illinois

    SciTech Connect

    1995-06-01

    The US Department of Energy (DOE) has prepared an Environmental Assessment (EA), evaluating the impacts associated with the proposed Low-Level Radioactive Waste Building at the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois. As a result of the high energy physics program at Fermilab, small quantities of low-level radioactive wastes are generated. These wastes are collected, sorted and packaged for shipment to an off-site disposal facility in Hanford, Washington. The proposed project includes the construction of a new building to house, all low-level radioactive waste handling operations. The building would provide workspace for five full-time workers. The proposed project would improve the efficiency and safety of the low-level radioactive waste handling at Fermilab by upgrading equipment and consolidating operations into one facility.

  8. Proposed Casey`s Pond Improvement Project, Fermi National Accelerator Laboratory

    SciTech Connect

    1995-05-01

    The U.S. Department of Energy (DOE) has prepared an Environmental Assessment (EA), evaluating the impacts associated with the proposed Casey`s Pond Improvement Project at the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois. The improvement project would maximize the efficiency of the Fermilab Industrial Cooling Water (ICW) distribution system, which removes (via evaporation) the thermal load from experimental and other support equipment supporting the high energy physics program at Fermilab. The project would eliminate the risk of overheating during fixed target experiments, ensure that the Illinois Water Quality Standards are consistently achieved and provide needed additional water storage for fire protection. Based on the analysis in the EA, the DOE has determined that the proposed action does not constitute a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an Environmental Impact Statement is not required.

  9. The Continuous Electron Beam Accelerator Facility: CEBAF at the Jefferson Laboratory

    SciTech Connect

    Leemann, Chrisoph; Douglas, David R; Krafft, Geoffrey A

    2001-08-01

    The Jefferson Laboratory's superconducting radiofrequency (srf) Continuous Electron Beam Accelerator Facility (CEBAF) provides multi-GeV continuous-wave (cw) beams for experiments at the nuclear and particle physics interface. CEBAF comprises two antiparallel linacs linked by nine recirculation beam lines for up to five passes. By the early 1990s, accelerator installation was proceeding in parallel with commissioning. By the mid-1990s, CEBAF was providing simultaneous beams at different but correlated energies up to 4 GeV to three experimental halls. By 2000, with srf development having raised the average cavity gradient up to 7.5 MV/m, energies up to nearly 6 GeV were routine, at 1-150 muA for two halls and 1-100 nA for the other. Also routine are beams of >75% polarization. Physics results have led to new questions about the quark structure of nuclei, and therefore to user demand for a planned 12 GeV upgrade. CEBAF's enabling srf technology is also being applied in other projects.

  10. Collisionless Magnetic Reconnection as an Ion Acceleration Mechanism of Low- β Laboratory Plasmas

    NASA Astrophysics Data System (ADS)

    Cazzola, Emanuele; Curreli, Davide; Lapenta, Giovanni

    2016-10-01

    In this work we present the results from a series of fully-kinetic simulations of magnetic reconnection under typical laboratory plasma conditions. The highly-efficient energy conversion obtained from this process is of great interest for applications such as future electric propulsion systems and ion beam accelerators. We analysed initial configurations in low-beta conditions with reduced mass ratio of mi = 512me at magnetic fields between 200G and 5000G and electron temperatures between 0.5 and 10eV. The initial ion density and temperature are kept uniform and equal to 1019 m-3 and 0.0215eV (room temperature) respectively. The analysis has shown that the reconnection process under these conditions can accelerate ions up to velocities as high as a significant fraction of the inflow Alfven speed. The configuration showing the best scenario is further studied with a realistic mass ratio in terms of energetics and outflow ion momentum, with the latter featured by the traditionally used specific impulse. Finally, a more detailed analysis of the reconnection outflow has revealed the formation of different interesting set of shock structures, also recently seen from MHD simulations of relativistic plasmas and certainly subject of future more careful attention. The present work has been possible thanks to the Illinois-KULeuven Faculty/PhD Candidate Exchange Program. Computational resources provided by the PRACE Tier-0 machines.

  11. Disruption of the Globular Cluster Pal 5

    NASA Technical Reports Server (NTRS)

    Miller, R. H.; Smith, B. F.; Cuzzi, Jeffrey N. (Technical Monitor)

    1995-01-01

    Orbit calculations suggest that the sparse globular cluster, Pal 5, will pass within 7 kpc of the Galactic center the next time it crosses the plane, where it might be destroyed by tidal stresses. We study this problem, treating Pal 5 as a self-consistent dynamical system orbiting through an external potential that represents the Galaxy. The first part of the problem is to find suitable analytic approximations to the Galactic potential. They must be valid in all regions the cluster is likely to explore. Observed velocity and positional data for Pal 5 are used as initial conditions to determine the orbit. Methods we used for a different problem some 12 years ago have been adapted to this problem. Three experiments have been run, with M/L= 1, 3, and 10, for the cluster model. The cluster blew up shortly after passing through the Galactic plane (about 130 Myrs after the beginning of the run) with M/L=1. At M/L = 3 and 10 the cluster survived, although it got quite a kick in the fundamental mode on passing through the plane. But the fundamental mode oscillation died out in a couple of oscillation cycles at M/L=10. Pal 5 will probably be destroyed on its next crossing of the Galactic plane if M/L=1, but it can survive (albeit with fairly heavy damage) if NI/L=3. We haven't tried to trap the mass limits more closely than that. Pal 5 comes through pretty well unscathed at M/L=10. An interesting follow-up experiment would be to back the cluster up along its orbit to look at its previous passage through the Galactic plane, to see what kind of object it might have been at earlier times.

  12. Advocacy for the Archives and History Office of the SLAC National Accelerator Laboratory: Stages and Methods

    SciTech Connect

    Deken, Jean Marie; /SLAC

    2009-06-19

    Advocating for the good of the SLAC Archives and History Office (AHO) has not been a one-time affair, nor has it been a one-method procedure. It has required taking time to ascertain the current and perhaps predict the future climate of the Laboratory, and it has required developing and implementing a portfolio of approaches to the goal of building a stronger archive program by strengthening and appropriately expanding its resources. Among the successful tools in the AHO advocacy portfolio, the Archives Program Review Committee has been the most visible. The Committee and the role it serves as well as other formal and informal advocacy efforts are the focus of this case study My remarks today will begin with a brief introduction to advocacy and outreach as I understand them, and with a description of the Archives and History Office's efforts to understand and work within the corporate culture of the SLAC National Accelerator Laboratory. I will then share with you some of the tools we have employed to advocate for the Archives and History Office programs and activities; and finally, I will talk about how well - or badly - those tools have served us over the past decade.

  13. A new LabVIEW-based control system for the Naval Research Laboratory Trace Element Accelerator Mass Spectrometer

    SciTech Connect

    DeTurck, T. M.; Treacy, D. J. Jr.; Knies, D. L.; Grabowski, K. S.; Knoll, C.; Kennedy, C. A.; Hubler, G. K.

    1999-06-10

    A new LabVIEW-based control system for the existing tandem accelerator and new AMS components has been implemented at the Trace Element Accelerator Mass Spectrometry (TEAMS) facility at the Naval Research Laboratory. Through the use of Device Interfaces (DIs) distributed along a fiber optic network, virtually every component of the accelerator system can be controlled from any networked computer terminal as well as remotely via modem or the internet. This paper discusses the LabVIEW-based control software, including remote operation, automatic calculation of ion optical component parameters, beam optimization, and data logging and retrieval.

  14. Improving quality management systems of laboratories in developing countries: an innovative training approach to accelerate laboratory accreditation.

    PubMed

    Yao, Katy; McKinney, Barbara; Murphy, Anna; Rotz, Phil; Wafula, Winnie; Sendagire, Hakim; Okui, Scolastica; Nkengasong, John N

    2010-09-01

    The Strengthening Laboratory Management Toward Accreditation (SLMTA) program was developed to promote immediate, measurable improvement in laboratories of developing countries. The laboratory management framework, a tool that prescribes managerial job tasks, forms the basis of the hands-on, activity-based curriculum. SLMTA is implemented through multiple workshops with intervening site visits to support improvement projects. To evaluate the effectiveness of SLMTA, the laboratory accreditation checklist was developed and subsequently adopted by the World Health Organization Regional Office for Africa (WHO AFRO). The SLMTA program and the implementation model were validated through a pilot in Uganda. SLMTA yielded observable, measurable results in the laboratories and improved patient flow and turnaround time in a laboratory simulation. The laboratory staff members were empowered to improve their own laboratories by using existing resources, communicate with clinicians and hospital administrators, and advocate for system strengthening. The SLMTA program supports laboratories by improving management and building preparedness for accreditation.

  15. Preliminary Evidence on the Social Standing of Students with Learning Disabilities in PALS and No-PALS Classrooms.

    ERIC Educational Resources Information Center

    Fuchs, Douglas; Fuchs, Lynn S.; Mathes, Patricia G.; Martinez, Elizabeth A.

    2002-01-01

    A study collected sociometric data in 39 second- through sixth-grade classrooms, 22 of which were engaged in Peer-Assisted Learning Strategies (PALS), a form of peer tutoring. Students with learning disabilities in PALS classes were more socially accepted than those in no-PALS classes and enjoyed the same social standing as controls. (Contains…

  16. Current status of the CXI beamline at the PAL-XFEL

    NASA Astrophysics Data System (ADS)

    Park, Jaehyun; Kim, Sangsoo; Nam, Ki-Hyun; Kim, Bongsoo; Ko, In Soo

    2016-09-01

    The Pohang Accelerator Laboratory's X-ray free electron laser (PAL-XFEL) is a research facility currently under construction. It will provide ultra-bright (1 × 1012 photons/pulse at 12.4 keV) and ultra-short (10 - 60 femtosecond) X-ray pulses. The CXI (coherent X-ray imaging) hard X-ray experimental station is designed to deliver brilliant hard X-rays (2 - 20.4 keV) and to measure diffraction signals with a forward scattering geometry. It will not only offer imaging studies of biological, chemical and physical samples with the "diffraction-before-destruction" scheme, but also be helpful in high-field hard X-ray physics and material science. The scientific programs are currently aimed at serial femtosecond crystallography (SFX) and coherent diffraction imaging (CDI) for bio specimens, nano materials, etc. In this paper, we describe the beamline layout, beam diagnostics, X-ray focusing optics, sample environments and detector system at the CXI experimental hutch.

  17. Application of the National Ignition Facility distinguishable-from-background program to accelerator facilities at Lawrence Livermore National Laboratory.

    PubMed

    Packard, Eric D; Mac Kenzie, Carolyn

    2013-06-01

    Lawrence Livermore National Laboratory must control potentially activated materials and equipment in accordance with U.S. Department of Energy (DOE) Order 458.1, Radiation Protection of the Public and the Environment, which requires DOE approval of the process used to release volumetrically contaminated personal property and establishes a dose constraint of 10 µSv y(-1) (1 mrem y(-1)) for clearance of such property. The National Ignition Facility at Lawrence Livermore National Laboratory developed a technical basis document and protocol for determining the radiological status of property that is potentially activated from exposure to neutron radiation produced via fusion of tritium and deuterium. The technical basis included assessment of the neutron energy, the type of materials potentially exposed and the likely activation products, and the sensitivity of radiation detectors used to survey the property. This paper evaluates the National Ignition Facility technical basis document for applicability to the release of property from Lawrence Livermore National Laboratory's various accelerator facilities considering the different types of particles accelerated, radiations produced, and resultant activation products. Extensive process knowledge regarding the accelerators' operations, accompanied by years of routine surveys, provides an excellent characterization of these facilities. Activation studies conducted at the Stanford Linear Accelerator and the High Energy Accelerator Research Organization in Japan corroborate that the long-lived radionuclides produced at accelerator facilities are of the same variety produced at the National Ignition Facility. Consequently, Lawrence Livermore National Laboratory concludes that the release protocol developed for the National Ignition Facility can be used appropriately at all its accelerator facilities.

  18. Ultra-trace analysis of (41)Ca in urine by accelerator mass spectrometry: an inter-laboratory comparison.

    PubMed

    Jackson, George S; Hillegonds, Darren J; Muzikar, Paul; Goehring, Brent

    2013-10-15

    A (41)Ca interlaboratory comparison between Lawrence Livermore National Laboratory (LLNL) and the Purdue Rare Isotope Laboratory (PRIME Lab) has been completed. Analysis of the ratios assayed by accelerator mass spectrometry (AMS) shows that there is no statistically significant difference in the ratios. Further, Bayesian analysis shows that the uncertainties reported by both facilities are correct with the possibility of a slight under-estimation by one laboratory. Finally, the chemistry procedures used by the two facilities to produce CaF2 for the cesium sputter ion source are robust and don't yield any significant differences in the final result.

  19. Linear induction accelerators at the Los Alamos National Laboratory DARHT facility

    SciTech Connect

    Nath, Subrata

    2010-09-07

    The Dual-Axis Radiographic Hydrodynamic Test Facility (DARHT) at Los Alamos National Laboratory consists of two linear induction accelerators at right angles to each other. The First Axis, operating since 1999, produces a nominal 20-MeV, 2-kA single beam-pulse with 60-nsec width. In contrast, the DARHT Second Axis, operating since 2008, produces up to four pulses in a variable pulse format by slicing micro-pulses out of a longer {approx}1.6-microseconds (flat-top) pulse of nominal beam-energy and -current of 17 MeV and 2 kA respectively. Bremsstrahlung x-rays, shining on a hydro-dynamical experimental device, are produced by focusing the electron beam-pulses onto a high-Z target. Variable pulse-formats allow for adjustment of the pulse-to-pulse doses to record a time sequence of x-ray images of the explosively driven imploding mock device. Herein, we present a sampling of the numerous physics and engineering aspects along with the current status of the fully operational dual axes capability. First successful simultaneous use of both the axes for a hydrodynamic experiment was achieved in 2009.

  20. Generation, transport, and detection of linear accelerator based femtosecond-terahertz pulses.

    PubMed

    Park, Jaehun; Kim, Changbum; Lee, Jongseok; Yim, Changmook; Kim, Chul Hoon; Lee, Junghwa; Jung, Seonghoon; Ryu, Jaehyun; Kang, Heung-Sik; Joo, Taiha

    2011-01-01

    The generation and detection of intense terahertz (THz) radiation has drawn a great attention recently. The dramatically enhanced energy and peak electric field of the coherent THz radiation can be generated by coherent superposition of radiated fields emitted by ultrafast electron bunches. The femtosecond (fs)-THz beamline construction at the Pohang Accelerator Laboratory (PAL) was completed in the end of 2009. The fs-THz beamline at PAL can supply ultrafast and intense fs-THz radiation from a 75 MeV linear accelerator. The radiation is expected to have frequency up to 3 THz (∼100 cm(-1)) and the pulse width of <200 fs with pulse energy up to 10 μJ. This intense THz source has great potential for applications in nonlinear optical phenomena and fields such as material science, biomedical science, chemistry, and physics, etc.

  1. Experimental setup for the laboratory investigation of micrometeoroid ablation using a dust accelerator

    NASA Astrophysics Data System (ADS)

    Thomas, Evan; Simolka, Jonas; DeLuca, Michael; Horányi, Mihály; Janches, Diego; Marshall, Robert A.; Munsat, Tobin; Plane, John M. C.; Sternovsky, Zoltan

    2017-03-01

    A facility has been developed to simulate the ablation of micrometeoroids in laboratory conditions. An electrostatic dust accelerator is used to generate iron particles with velocities of 10-70 km/s. The particles are then introduced into a chamber pressurized with a target gas, where the pressure is adjustable between 0.01 and 0.5 Torr, and the particle partially or completely ablates over a short distance. An array of biased electrodes above and below the ablation path is used to collect the generated ions/electrons with a spatial resolution of 2.6 cm along the ablating particles' path, thus allowing the study of the spatiotemporal evolution of the process. For completely ablated particles, the total collected charge directly yields the ionization coefficient of a given dust material-target gas combination. The first results of this facility measured the ionization coefficient of iron atoms with N2, air, CO2, and He target gases for impact velocities >20 km/s, and are reported by Thomas et al. [Geophys. Res. Lett. 43, 3645 (2016)]. The ablation chamber is also equipped with four optical ports that allow for the detection of the light emitted by the ablating particle. A multichannel photomultiplier tube system is used to observe the ablation process with a spatial and temporal resolution of 0.64 cm and 90 ns. The preliminary results indicate that it is possible to calculate the velocity of the ablating particle from the optical observations, and in conjunction with the spatially resolved charge measurements allow for experimental validation of ablation models in future studies.

  2. Actinide Measurements by Accelerator Mass Spectrometry at Lawrence Livermore National Laboratory

    SciTech Connect

    Brown, T A; Marchetti, A A; Martinelli, R E; Cox, C C; Knezovich, J P; Hamilton, T F

    2003-09-25

    We report on the development of an accelerator mass spectrometry (AMS) system for the measurement of actinides at Lawrence Livermore National Laboratory. This AMS system is centered on a recently completed heavy isotope beam line that was designed particularly for high sensitivity, robust, high-throughput measurements of actinide concentrations and isotopic ratios. A fast isotope switching capability has been incorporated in the system, allowing flexibility in isotope selection and for the quasi-continuous normalization to a reference isotope spike. Initially, our utilization of the heavy isotope system has concentrated on the measurement of Pu isotopes. Under current operating conditions, background levels equivalent to {approx}1 x 10{sup 5} atoms are observed during routine {sup 239}Pu and {sup 240}Pu measurements. Measurements of samples containing {approx}10{sup 13} {sup 238}U atoms demonstrate that the system provides a {sup 238}U rejection factor during {sup 239}Pu measurements of {approx}10{sup 7}. Measurements of known materials, combined with results from an externally organized inter-comparison program, indicate that our {sup 239}Pu measurements are accurate and precise down to the {micro}Bq level ({approx}10{sup 6} atoms). Recently, we have investigated the performance of our heavy isotope AMS system in measurements of {sup 237}Np and {sup 236}U. Results of these investigations are discussed. The sensitivity shown by our Pu measurements, combined with the high throughput and interference rejection capabilities of our AMS system, demonstrate that AMS can provide a rapid and cost-effective measurement technique for actinides in a wide variety of studies.

  3. Evaluation of splashzone maintenance coating systems by accelerated laboratory testing and field trials

    SciTech Connect

    Tischuk, J.L.; Brebner, G.

    1983-09-01

    Maintenance painting of platform splashzones is one of the most difficult offshore coating problems. There is a limited and frequently interrupted weather window for working, the temperature is generally low, the relative humidity is usually high and surfaces may be subjected to salt spray or complete immersion within a few hours of coating application. Once a coating is on the steel, it is continually wet and must resist abrasion and impact from the sea and from debris which is in the sea. In order to stand up to these conditions, splashzone coatings must adhere tightly to the steel, they must be tough and resilient and they must be resistant to the spread of local damage. Occidental's Piper and Claymore Platforms were installed in the North Sea in 1976 and 1977 respectively. The original splashzone coatings applied during fabrication were high-build vinyl systems over zinc silicate primers. The same coating systems were used on the platform topsides. By 1978 there was a need for coating repairs because the vinyls had poor abrasion resistance. It has proved impossible to use the original coating system for the repairs because it is intolerant of ambient conditions. Major maintenance painting programmes were planned for both platform splashzones in 1983. Surveys had shown that both splashzones required blasting to bare metal and recoating. Field trials and accelerated laboratory tests were used to select a coating system for the platform splashzones from nine alternative systems. The materials tested were ones presented by major manufacturers as their recommended splashzone systems. The coating systems ranged from coal tar epoxies to a very-high-technology system of primer injected into the grit-blasting nozzle followed by a single coat of high-build, solvent-free epoxy. Detailed descriptions of the coating systems are given in Table 1.

  4. [Social change and Pharmaceutical Affairs Law (PAL)].

    PubMed

    Masuyama, Koichi; Isobe, Soichiro

    2010-01-01

    Former Japanese pharmaceutical laws, originally based on the Pharmaceutical Marketing and Handling Regulations enacted in 1874 were in operation for many years before World War II. However, in order to address several drug issues, such as poor drug quality and insufficiences regarding the role of pharmacists during the War, the laws needed to be unified and revised. In this paper, we analyzed the record of discussions held by the Imperial Diet on the bill for the Pharmaceutical Affairs Law (PAL) in 1943. This is also regarded as the origin of the current PAL (LawNo.145 in 1960). Through this analysis, we tried to clarify the relationship between the social change and the role of PAL in society. During the War, the bill was discussed, aiming at the improvement of both human resources who treated drugs, and the quality of drug materials. Diet members discussed three main points, namely, "the duty of pharmacists", "the mission of the Japan Pharmaceutical Association" and "the quality control of pharmaceutical products". Notably, the bill pharmacists are required not only to dispense drugs, a role they had previously, but also to manage drug and food hygiene through the quality control of pharmaceutical products and the inspection of food and drink, in order to improve the public health in Japan. Originally, the law was passed to deal with the extraordinary circumstances during the War, but through our analysis, we found that they proactively improved the role of the law to comply with various drug issues raised during the War, the rapid change of the pharmaceutical hygiene concept and the social transformation.

  5. TweezPal - Optical tweezers analysis and calibration software

    NASA Astrophysics Data System (ADS)

    Osterman, Natan

    2010-11-01

    Optical tweezers, a powerful tool for optical trapping, micromanipulation and force transduction, have in recent years become a standard technique commonly used in many research laboratories and university courses. Knowledge about the optical force acting on a trapped object can be gained only after a calibration procedure which has to be performed (by an expert) for each type of trapped objects. In this paper we present TweezPal, a user-friendly, standalone Windows software tool for optical tweezers analysis and calibration. Using TweezPal, the procedure can be performed in a matter of minutes even by non-expert users. The calibration is based on the Brownian motion of a particle trapped in a stationary optical trap, which is being monitored using video or photodiode detection. The particle trajectory is imported into the software which instantly calculates position histogram, trapping potential, stiffness and anisotropy. Program summaryProgram title: TweezPal Catalogue identifier: AEGR_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEGR_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 44 891 No. of bytes in distributed program, including test data, etc.: 792 653 Distribution format: tar.gz Programming language: Borland Delphi Computer: Any PC running Microsoft Windows Operating system: Windows 95, 98, 2000, XP, Vista, 7 RAM: 12 Mbytes Classification: 3, 4.14, 18, 23 Nature of problem: Quick, robust and user-friendly calibration and analysis of optical tweezers. The optical trap is calibrated from the trajectory of a trapped particle undergoing Brownian motion in a stationary optical trap (input data) using two methods. Solution method: Elimination of the experimental drift in position data. Direct calculation of the trap stiffness from the positional

  6. Corrosion Screening of EV31A Magnesium and Other Magnesium Alloys using Laboratory-Based Accelerated Corrosion and Electro-Chemical Methods

    DTIC Science & Technology

    2014-07-01

    Corrosion Screening of EV31A Magnesium and Other Magnesium Alloys Using Laboratory-Based Accelerated Corrosion and Electro-chemical Methods...originator. Army Research Laboratory Aberdeen Proving Ground, MD 21005-5066 ARL-TR-6899 July 2014 Corrosion Screening of EV31A...Magnesium and Other Magnesium Alloys Using Laboratory-Based Accelerated Corrosion and Electro-chemical Methods Brian E. Placzankis, Joseph P

  7. LLNL/UC (Lawrence Livermore National Laboratory)/(University of California) AMS (accelerator mass spectrometry) facility and research program

    SciTech Connect

    Davis, J.C.; Proctor, I.D.; Southon, J.R.; Caffee, M.W.; Heikkinen, D.W.; Roberts, M.L.; Moore, T.L.; Turteltaub, K.W.; Nelson, D.E.; Loyd, D.H.; Vogel, J.S.

    1990-04-18

    The Lawrence Livermore National Laboratory (LLNL) and the University of California (UC) now have in operation a large AMS spectrometer built as part of a new multiuser laboratory centered on an FN tandem. AMS measurements are expected to use half of the beam time of the accelerator. LLNL use of AMS is in research on consequences of energy usage. Examples include global warming, geophysical site characterization, radiation biology and dosimetry, and study of mutagenic and carcinogenic processes. UC research activities are in clinical applications, archaeology and anthropology, oceanography, and geophysical and geochemical research. Access is also possible for researchers outside the UC system. The technological focus of the laboratory is on achieving high rates of sample through-put, unattended operation, and advances in sample preparation methods. Because of the expected growth in the research programs and the other obligations of the present accelerator, we are designing a follow-on dedicated facility for only AMS and microprobe analysis that will contain at least two accelerators with multiple spectrometers. 10 refs., 1 fig.

  8. Implementation of an electronic laboratory notebook to accelerate data review in bioanalysis.

    PubMed

    Shoup, Ronald E; Beato, Brian D; Pisek, April; White, Jessica; Branstrator, Laurel; Bousum, Abby; Roach, Jasmine; Grever, Tim

    2013-07-01

    Electronic laboratory notebooks increase opportunities for collaboration and information exchange when compared with paper records. Depending on the degree of implementation, a laboratory- or enterprise-wide system can unify the collection, review and dissemination of data to improve laboratory efficiency and productivity. The advantages of an electronic laboratory notebook for speeding data review in bioanalysis are discussed, through the use of validated templates and organizational constructs to block errors in real-time and reduce manual audit tasks.

  9. Health-based Provisional Advisory Levels (PALs) for Homeland Security

    SciTech Connect

    Adeshina, Femi; Sonich-Mullin, Synthia; Wood, Carol S

    2009-01-01

    In compliance with Homeland Security Presidential Directive No.8, the US EPA National Homeland Security Research Center, in collaboration with the Department of Energy, is developing health-based Provisional Advisory Levels (PALs) for priority toxic industrial chemicals, pesticides, and chemical warfare agents in air and drinking water. The PALs Program will provide exposure levels to assist emergency response decision-making, and to serve as criteria for determining re-use and re-entry into affected areas resulting from transport/storage accidents, natural disasters, and subversive activities. PALs are applicable at federal, state, and local levels, and are intended for use in homeland security efforts, public health, law enforcement, and emergency response, as well as decisions by water utilities, and national and regional EPA offices. PALS have not been promulgated nor have they been formally issued as regulatory guidance. They are intended to be used at the discretion of risk managers in emergency situations when site specific risk assessments are not available. Three levels (PAL 1, PAL 2, and PAL 3), distinguished by severity of toxic effects, are developed for 24-hour, 30-day, 90-day, and 2-year durations of potential drinking water and inhalation exposures for the general public. Draft PALs are evaluated both by an EPA working group, and an external multidisciplinary panel to ensure scientific credibility and wide acceptance. In this issue, we present background information on the PAL program, the methodology used in deriving PALs, and the technical support documents for the derivation of PALs for acrylonitrile, phosgene, hydrogen chloride, and hydrogen sulfide.

  10. Accelerator Development for the NRL (Naval Research Laboratory) Free Electron Laser Program

    DTIC Science & Technology

    1988-06-01

    34triple point" junction of the vacuum , ceramic insulator , and metal electrode. This leads to the flashover of the insulator , causing an arc which acts as...tungsten wire (25.4 um) into the transport vacuum system. The diode is housed in an Astron ceramic insulator stack. The voltage profile across the diode...accelerator vacuum wall. It is across these insulating breaks that the accelerating voltage is applied to the electron beam and any breakdown in these gaps

  11. INFN - P.L.A.I.A. PROJECT (Plasma Laser Ablation for Ion Acceleration)

    NASA Astrophysics Data System (ADS)

    Torrisi, L.; Gammino, S.; Andò, L.; Ciavola, G.; Mezzasalma, A. M.; Nassisi, V.; Wolowski, J.; Parys, P.; Laska, L.; Krasa, J.; Boody, F. P.

    2004-10-01

    The INFN-Gr.V PLAIA (Plasma Laser Ablation for Ion Acceleration) Project is presented and discussed. The project is developing at LNS of Catania, Messina and Lecce Laboratories as Italian centers of research and it see as European partners the PALS Laboratory of Prague and the group of researchers coordinated by Prof. Wolowsky from IPPLM of Warsaw. PLAIA concerns the study of pulsed plasma produced by pulsed lasers and some special applications of this physics to the new generation of ion sources. Different lasers are employed at LNS of Catania, LEA of Lecce and PALS of Prague. Their fluences range from about 10 J/cm2 for the excimer lasers of LEA up to about 100 kj/cm2 for the iodine laser of PALS. The Nd:Yag laser of LNS, operating at 1064 nm, 9 ns pulse width and 900 mJ maximum pulse energy shows peculiar properties, specially if it is employed at 30 Hz repetition rate, at which it may produce stabile current of ions ejected from a dense plasma. Such laser has the optimum compromise between power density and repetition rate to be used as injector of ions in ECR sources or as source of a new generation of ion implanters which can be employed to accelerate multi-energetic ion beams useful to treat the surface of different materials. Results and projects are discussed in detail.

  12. Guide for Peer Assisted Learning (PAL) Group Facilitators

    ERIC Educational Resources Information Center

    Arendale, David R., Ed.; Lilly, Mary, Ed.

    2014-01-01

    The Peer Assisted Learning (PAL) program at the University of Minnesota is a primary academic support program for historically difficult, introductory college courses that serve as gatekeepers to academic degree programs. This document is the training manual used for the new PAL facilitators that manage the small study groups. Based upon operating…

  13. Health-based Provisional Advisory Levels (PALs) for homeland security.

    PubMed

    Adeshina, Femi; Sonich-Mullin, Cynthia; Ross, Robert H; Wood, Carol S

    2009-12-01

    The Homeland Security Presidential Directive #8 (HSPD-8) for National Emergency Preparedness was issued to " establish policies to strengthen the preparedness of the United States to prevent and respond to threatened or actual domestic terrorist attacks, major disasters, and other emergencies by requiring a national domestic all- hazards preparedness goal. "In response to HSPD-8 and HSPD-22 (classified) on Domestic Chemical Defense, the US Environmental Protection Agency (US EPA) National Homeland Security Research Center (NHSRC) is developing health-based Provisional Advisory Levels (PALs) for priority chemicals (including chemical warfare agents, pesticides, and toxic industrial chemicals) in air and drinking water. PALs are temporary values that will neither be promulgated, nor be formally issued as regulatory guidance. They are intended to be used at the discretion of risk managers in emergency situations. The PAL Program provides advisory exposure levels for chemical agents to assist in emergency planning and response decision-making, and to aid in making informed risk management decisions for evacuation, temporary re-entry into affected areas, and resumed-use of infrastructure, such as water resources. These risk management decisions may be made at the federal, state, and local levels. Three exposure levels (PAL 1, PAL 2, and PAL 3), distinguished by severity of toxic effects, are developed for 24-hour, 30-day, 90-day, and 2-year durations for potential exposure to drinking water and ambient air by the general public. Developed PALs are evaluated both by a US EPA working group, and an external multidisciplinary panel to ensure scientific credibility and wide acceptance. In this Special Issue publication, we present background information on the PAL program, the methodology used in deriving PALs, and the technical support documents for the derivation of PALs for acrylonitrile, hydrogen sulfide, and phosgene.

  14. Progress Towards a Laboratory Test of Alfvénic Electron Acceleration

    NASA Astrophysics Data System (ADS)

    Schroeder, J. W. R.; Skiff, F.; Howes, G. G.; Kletzing, C. A.; Carter, T. A.; Vincena, S.; Dorfman, S.

    2016-10-01

    Alfvén waves are thought to be a key mechanism for accelerating auroral electrons. Due to inherent limitations of single point measurements, in situ data has been unable to demonstrate a causal relationship between Alfvén waves and accelerated electrons. Electron acceleration occurs in the inner magnetosphere where the Alfvén speed is greater than the electron thermal speed. In these conditions, Alfvén waves can have an electric field aligned with the background magnetic field B0 if the scale of wave structure across B0 is comparable to the electron skin depth. In the Large Plasma Device (LaPD), Alfvén waves are launched in conditions relevant to the inner magnetosphere. The reduced parallel electron distribution function is measured using a whistler-mode wave absorption diagnostic. The linear electron response has been measured as oscillations of the electron distribution function at the Alfvén wave frequency. These measurements agree with linear theory. Current efforts focus on measuring the nonlinear acceleration of electrons that is relevant to auroral generation. We report on recent progress including experiments with a new higher-power Alfvén wave antenna with the goal of measuring nonlinear electron acceleration. This work was supported by the NSF GRFP and by Grants from NSF, DOE, and NASA. Experiments were performed at the Basic Plasma Science Facility which is funded by DOE and NSF.

  15. Particle heating and acceleration during collisionless reconnection in a laboratory plasma

    NASA Astrophysics Data System (ADS)

    Yoo, Jongsoo

    2013-10-01

    Particle heating and acceleration during magnetic reconnection is studied in the collisionless plasma of the Magnetic Reconnection Experiment (MRX). For ion heating and acceleration, the role of the in-plane (Hall) electric field is emphasized. An in-plane electrostatic potential profile is established by electron acceleration near the X-point. The potential profile shows a well structure along the direction normal to the reconnection current sheet that becomes deeper and wider downstream as its boundary expands along the separatrices where the in-plane electric field is strongest. The Hall electric field ballistically accelerates ions near the separatrices toward the outflow direction. After ions are accelerated, they are heated as they travel into the high-pressure downstream region due to an effect called re-magnetization. Electrons are also significantly heated during reconnection. The electron temperature sharply increases across the separatrices and peaks just outside of the electron diffusion region. Classical Ohmic dissipation based on the perpendicular Spitzer resistivity is too small to compensate for the energy loss by parallel heat conduction, indicating the presence of anomalous electron heating. Finally, a total energy inventory is calculated based on analysis of the Poynting, enthalpy, flow energy, and heat flux in the measured diffusion layer. More than half of the incoming magnetic energy is converted to particle energy during reconnection. The author thanks contributions from M. Yamada, H. Ji, J. Jara-Almonte, and C. E. Myers. This work is supported by DOE and NSF.

  16. Do sediment type and test durations affect results of laboratory-based, accelerated testing studies of permeable pavement clogging?

    PubMed

    Nichols, Peter W B; White, Richard; Lucke, Terry

    2015-04-01

    Previous studies have attempted to quantify the clogging processes of Permeable Interlocking Concrete Pavers (PICPs) using accelerated testing methods. However, the results have been variable. This study investigated the effects that three different sediment types (natural and silica), and different simulated rainfall intensities, and testing durations had on the observed clogging processes (and measured surface infiltration rates) of laboratory-based, accelerated PICP testing studies. Results showed that accelerated simulated laboratory testing results are highly dependent on the type, and size of sediment used in the experiments. For example, when using real stormwater sediment up to 1.18 mm in size, the results showed that neither testing duration, nor stormwater application rate had any significant effect on PICP clogging. However, the study clearly showed that shorter testing durations generally increased clogging and reduced the surface infiltration rates of the models when artificial silica sediment was used. Longer testing durations also generally increased clogging of the models when using fine sediment (<300 μm). Results from this study will help researchers and designers better anticipate when and why PICPs are susceptible to clogging, reduce maintenance and extend the useful life of these increasingly common stormwater best management practices.

  17. Dissociating Crossmodal and Verbal Demands in Paired Associate Learning (PAL): What Drives the PAL-Reading Relationship?

    ERIC Educational Resources Information Center

    Litt, Robin A.; de Jong, Peter F.; van Bergen, Elsje; Nation, Kate

    2013-01-01

    Recent research suggests that visual-verbal paired associate learning (PAL) may tap a crossmodal associative learning mechanism that plays a distinct role in reading development. However, evidence from children with dyslexia indicates that deficits in visual-verbal PAL are strongly linked to the verbal demands of the task. The primary aim of this…

  18. The MIT Accelerator Laboratory for Diagnostic Development for OMEGA, Z and the NIF

    NASA Astrophysics Data System (ADS)

    Petrasso, R.; Gatu Johnson, M.; Armstrong, E.; Orozco, D.; Rinderknecht, H. G.; Rojas Herrera, J.; Rosenberg, M.; Sio, H.; Zylstra, A.; Frenje, J.; Li, C. K.; Seguin, F. H.; Hahn, K.; Jones, B.; Ruiz, C. L.; Sangster, T. C.

    2014-10-01

    The MIT Linear Electrostatic Ion Accelerator generates D-D and D-3He fusion products, which are used for development of nuclear diagnostics for OMEGA, Z, and the NIF. Fusion reaction rates around 106 s-1 are routinely achieved with this accelerator, and fluence and energy of the fusion products are accurately characterized. Diagnostics developed and calibrated at this facility include CR-39 based charged-particle spectrometers, neutron detectors, and the particle Time-Of-Flight (pTOF) CVD-diamond-based bang time detector. The accelerator is also a vital tool in the education of graduate and undergraduate students at MIT. This work was supported in part by SNL, DOE, LLE and LLNL.

  19. General Corrosion Resistance Comparisons of Medium- and High-Strength Aluminum Alloys for DOD Systems Using Laboratory-Based Accelerated Corrosion Methods

    DTIC Science & Technology

    2009-09-01

    General Corrosion Resistance Comparisons of Medium- and High-Strength Aluminum Alloys for DOD Systems Using Laboratory-Based Accelerated... Aluminum Alloys for DOD Systems Using Laboratory-Based Accelerated Corrosion Methods Brian E. Placzankis Weapons and Materials Research Directorate...March 2006–October 2008 4. TITLE AND SUBTITLE General Corrosion Resistance Comparisons of Medium- and High-Strength Aluminum Alloys for DOD

  20. Rapid Acceleration Leads to Rapid Weakening in Earthquake-Like Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Chang, J. C.; Lockner, D. A.; Reches, Z.

    2012-10-01

    After nucleation, a large earthquake propagates as an expanding rupture front along a fault. This front activates countless fault patches that slip by consuming energy stored in Earth’s crust. We simulated the slip of a fault patch by rapidly loading an experimental fault with energy stored in a spinning flywheel. The spontaneous evolution of strength, acceleration, and velocity indicates that our experiments are proxies of fault-patch behavior during earthquakes of moment magnitude (Mw) = 4 to 8. We show that seismically determined earthquake parameters (e.g., displacement, velocity, magnitude, or fracture energy) can be used to estimate the intensity of the energy release during an earthquake. Our experiments further indicate that high acceleration imposed by the earthquake’s rupture front quickens dynamic weakening by intense wear of the fault zone.

  1. Rapid acceleration leads to rapid weakening in earthquake-like laboratory experiments.

    PubMed

    Chang, J C; Lockner, D A; Reches, Z

    2012-10-05

    After nucleation, a large earthquake propagates as an expanding rupture front along a fault. This front activates countless fault patches that slip by consuming energy stored in Earth's crust. We simulated the slip of a fault patch by rapidly loading an experimental fault with energy stored in a spinning flywheel. The spontaneous evolution of strength, acceleration, and velocity indicates that our experiments are proxies of fault-patch behavior during earthquakes of moment magnitude (M(w)) = 4 to 8. We show that seismically determined earthquake parameters (e.g., displacement, velocity, magnitude, or fracture energy) can be used to estimate the intensity of the energy release during an earthquake. Our experiments further indicate that high acceleration imposed by the earthquake's rupture front quickens dynamic weakening by intense wear of the fault zone.

  2. Rapid acceleration leads to rapid weakening in earthquake-like laboratory experiments

    NASA Astrophysics Data System (ADS)

    Chang, J. C.; Lockner, D. A.; Reches, Z.

    2012-12-01

    We simulated the slip of a fault-patch during a large earthquake by rapidly loading an experimental, ring-shaped fault with energy stored in a spinning flywheel. The flywheel abruptly delivers a finite amount of energy by spinning the fault-patch that spontaneously dissipates the energy without operator intervention. We conducted 42 experiments on Sierra White granite (SWG) samples, and 24 experiments on Kasota dolomite (KD) samples. Each experiment starts by spinning a 225 kg disk-shaped flywheel to a prescribed angular velocity. We refer to this experiment as an "earthquake-like slip-event" (ELSE). The strength-evolution in ELSE experiments is similar to the strength-evolution proposed for earthquake models and observed in stick-slip experiments. Further, we found that ELSE experiments are similar to earthquakes in at least three ways: (1) slip driven by the release of a finite amount of stored energy; (2) pattern of fault strength evolution; and (3) seismically observed values, such as average slip, peak-velocity and rise-time. By assuming that the measured slip, D, in ELSE experiments is equivalent to the average slip during an earthquake, we found that ELSE experiments (D = 0.003-4.6 m) correspond to earthquakes in moment-magnitude range of Mw = 4-8. In ELSE experiments, the critical-slip-distance, dc, has mean values of 2.7 cm and 1.2 cm for SWG and KD, that are much shorter than the 1-10 m in steady-state classical experiments in rotary shear systems. We attribute these dc values, to ELSE loading in which the fault-patch is abruptly loaded by impact with a spinning flywheel. Under this loading, the friction-velocity relations are strikingly different from those under steady-state loading on the same rock samples with the same shear system (Reches and Lockner, Nature, 2010). We further note that the slip acceleration in ELSE evolves systematically with fault strength and wear-rate, and that the dynamic weakening is restricted to the period of intense

  3. Rapid acceleration leads to rapid weakening in earthquake-like laboratory experiments

    USGS Publications Warehouse

    Chang, Jefferson C.; Lockner, David A.; Reches, Z.

    2012-01-01

    After nucleation, a large earthquake propagates as an expanding rupture front along a fault. This front activates countless fault patches that slip by consuming energy stored in Earth’s crust. We simulated the slip of a fault patch by rapidly loading an experimental fault with energy stored in a spinning flywheel. The spontaneous evolution of strength, acceleration, and velocity indicates that our experiments are proxies of fault-patch behavior during earthquakes of moment magnitude (Mw) = 4 to 8. We show that seismically determined earthquake parameters (e.g., displacement, velocity, magnitude, or fracture energy) can be used to estimate the intensity of the energy release during an earthquake. Our experiments further indicate that high acceleration imposed by the earthquake’s rupture front quickens dynamic weakening by intense wear of the fault zone.

  4. Recent Developments on ALICE (Accelerators and Lasers In Combined Experiments) at Daresbury Laboratory

    SciTech Connect

    Saveliev, Y M; Buckley, R K; Buckley, S R; Clarke, J A; Corlett, P A; Dunning, D J; Goulden, A R; Hill, S F; Jackson, F; Jamison, S P; Jones, J K; Jones, L B; Leonard, S; McIntosh, P A; McKenzie, J W; Middleman, K J; Militsyn, B L; Moss, A J; Muratori, B D; Orrett, J F; Pattalwar, S M; Phillips, P J; Scott, D J; Seddon, E A; Shepherd, B.J.A.; Smith, S L; Thompson, N; Wheelhouse, A E; Williams, P H; Harrison, P; Holder, D J; Holder, G M; Schofield, A L; Weightman, P; Williams, R L; Laundry, D; Powers, T; Priebe, G; Surman, M

    2010-05-01

    Progress made in ALICE (Accelerators and Lasers In Combined Experiments) commissioning and a summary of the latest experimental results are presented in this paper. After an extensive work on beam loading effects in SC RF linac (booster) and linac cavities conditioning, ALICE can now operate in full energy recovery mode at the bunch charge of 40pC, the beam energy of 30MeV and train lengths of up to 100us. This improved operation of the machine resulted in generation of coherently enhanced broadband THz radiation with the energy of several tens of uJ per pulse and in successful demonstration of the Compton Backscattering x-ray source experiment. The next steps in the ALICE scientific programme are commissioning of the IR FEL and start of the research on the first non-scaling FFAG accelerator EMMA. Results from both projects will be also reported.

  5. Experiments assigned to determine the acceleration of 8000kN shear laboratory model elements

    NASA Astrophysics Data System (ADS)

    Budiul Berghian, A.; Vasiu, T.; Abrudean, C.

    2017-01-01

    In this paper presents an experimental kinetics study by measuring accelerations using a bi-axial accelerometer constructed in the basis of a miniature integrated circuit, included in the class of micro-electrical and mechanical systems - MMA6261Q on the experimental installation reduced to the 1:5 dividing rule by comparison with the shear existent in exploitation, conceived and projected at the Faculty of Engineering in Hunedoara.

  6. Simulation of the laser acceleration experiment at the Fermilab/NICADD photoinjector laboratory

    SciTech Connect

    Piot, P.; Tikhoplav, R.; Melissinos, A.C.; /Rochester U.

    2005-05-01

    The possibility of using laser beam to accelerate electrons in a waveguide structure with dimension much larger than the laser wavelength was proposed by Pantel and analytically investigated by Xie. In the present paper we present the status of our experimental plan to demonstrate the laser/e{sup -} interaction using an e{sup -} beam with initial energy of 40-50 MeV.

  7. Performance of the accelerator driver of Jefferson Laboratory's Free-Electron Laser

    SciTech Connect

    Bohn, C L

    1998-09-01

    The driver for Jefferson Lab's infrared free-electron laser is a superconducting, recirculating accelerator that recovers about 75% of the electron-beam energy and converts it to radiofrequency power. It is designed to lase continuous-wave at 3--6 {mu}m at kW-level power. In achieving first light, the accelerator operated straight ahead to deliver 38 MeV, 1.1 mA cw current through the wiggler for lasing at wavelengths in the vicinity of 5 {mu}m. The waste beam was then sent directly to a dump, bypassing the recirculation loop. Stable operation at power levels up to 311 W cw have thus far been achieved in this mode. The accelerator has recently recirculated up to 0.6 mA cw current with energy recovery. In this mode it has lased pulsed and cw at low-power. It remains to clean up the transport for high-power cw lasing.

  8. Particle optics and accelerator modeling software for industrial and laboratory beamline design

    NASA Astrophysics Data System (ADS)

    Gillespie, George H.; Hill, Barrey W.

    1998-04-01

    The expanding variety of accelerator applications in research and industry places increased demands upon scientists and engineers involved in developing new accelerator and beamline designs. Computer codes for particle optics simulation have always played an important role in the design process and enhanced software tools offer the promise of improved productivity for beamline designers. This paper summarizes recent work on the development of advanced graphic user interface (GUI) software components, that can be linked directly to many of the standard particle optics programs used in the accelerator community, and which are aimed at turning that promise of improved productivity into a reality. An object oriented programming (OOP) approach has been adopted and a number of GUI components have been developed that run on several different operating systems. The emphasis is on assisting users in the setup and running of the optics programs without requiring any knowledge of the format, syntax, or similar requirements of the input. The components are being linked with several popular optics programs, including TRANSPORT, TURTLE, TRACE 3-D and PARMILA, to form integrated easy-to-use applications. Several advanced applications linking the GUI components with Lie algebra and other high-order simulation codes, as well as system level and facility modeling codes, are also under development. An overview of the work completed to date is presented, and examples of the new tools running on the Windows 95 operating system are illustrated.

  9. Accelerated nervous system development contributes to behavioral efficiency in the laboratory mouse: a behavioral review and theoretical proposal.

    PubMed

    Whishaw, I Q; Metz, G A; Kolb, B; Pellis, S M

    2001-11-01

    The emergence of the laboratory mouse as a favored species for genetic research has posed a number of problems for scientists interested in the reflection of genetic influences in mouse behavior. It is commonly thought that rat behavior, which has been studied more extensively than mouse behavior, could be easily generalized to mice. In this article, a number of categories of behavior displayed by the mouse (motor, spatial, defensive, social) are reviewed and contrasted with the same categories of behavior displayed by the rat. The comparison suggests that mouse behavior is simpler and more dependent upon elementary actions than the behavior of the rat. We suggest that the behavioral simplification in the mouse adapts it for a different ecological niche than that occupied by the rat. We propose that this simplification may be mediated by accelerated brain maturation during development. We further propose that this developmental acceleration in the mouse renders it less dependent upon complex social behavior and plastic nervous system changes associated with learning than the rat. This difference poses problems for the development of relevant methods of behavioral analysis and interpretation. Since the mouse's biological adaptations will be reflected in laboratory behavior, suggestions are made for behavioral approaches to the study and interpretation of mouse behavior.

  10. Can Accelerators Accelerate Learning?

    NASA Astrophysics Data System (ADS)

    Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S.

    2009-03-01

    The 'Young Talented' education program developed by the Brazilian State Funding Agency (FAPERJ) [1] makes it possible for high-schools students from public high schools to perform activities in scientific laboratories. In the Atomic and Molecular Physics Laboratory at Federal University of Rio de Janeiro (UFRJ), the students are confronted with modern research tools like the 1.7 MV ion accelerator. Being a user-friendly machine, the accelerator is easily manageable by the students, who can perform simple hands-on activities, stimulating interest in physics, and getting the students close to modern laboratory techniques.

  11. Validation of activPAL defined sedentary time and breaks in sedentary time in 4- to 6-year-olds.

    PubMed

    Janssen, Xanne; Cliff, Dylan P; Reilly, John J; Hinkley, Trina; Jones, Rachel A; Batterham, Marijka; Ekelund, Ulf; Brage, Soren; Okely, Anthony D

    2014-02-01

    This study examined the classification accuracy of the activPAL, including total time spent sedentary and total number of breaks in sedentary behavior (SB) in 4- to 6-year-old children. Forty children aged 4-6 years (5.3 ± 1.0 years) completed a ~150-min laboratory protocol involving sedentary, light, and moderate- to vigorous-intensity activities. Posture was coded as sit/lie, stand, walk, or other using direct observation. Posture was classified using the activPAL software. Classification accuracy was evaluated using sensitivity, specificity and area under the receiver operating characteristic curve (ROC-AUC). Time spent in each posture and total number of breaks in SB were compared using paired sample t-tests. The activPAL showed good classification accuracy for sitting (ROC-AUC = 0.84) and fair classification accuracy for standing and walking (0.76 and 0.73, respectively). Time spent in sit/lie and stand was overestimated by 5.9% (95% CI = 0.6-11.1%) and 14.8% (11.6-17.9%), respectively; walking was underestimated by 10.0% (-12.9-7.0%). Total number of breaks in SB were significantly overestimated (55 ± 27 over the course of the protocol; p < .01). The activPAL performed well when classifying postures in young children. However, the activPAL has difficulty classifying other postures, such as kneeling. In addition, when predicting time spent in different postures and total number of breaks in SB the activPAL appeared not to be accurate.

  12. Laboratory Experiments with the Concordia College High-Speed Dust Particle Accelerator

    NASA Astrophysics Data System (ADS)

    Manning, H. L.

    2011-12-01

    During the Apollo Era, NASA's Goddard Space Flight Center built a 2MeV high-speed, dust particle accelerator. This facility was used to test and calibrate the LEAM instrument which was flown to the lunar surface by Apollo 17. As the Apollo project wound down, NASA no longer had need of the dust particle accelerator, and in 1975, it was move to Concordia College in Moorhead, MN. Through the years, it has been maintained and some modifications and improvements have been made to it. In the past decade, the facility has been revived and used by several collaborating institutions to study dust detector instrumentation as well as the effects of dust impacts on various materials. We have tested a prototype, space-flight dust particle detector. Also, piezoelectric pins which can be used as dust detectors were studied to learn the pin's response to single particle impacts of different energies and momenta, and then those measured responses were compared with theoretical models. The effects of high speed impacts on ultra-high temperature ceramics, aerogel, and several different thin films have also been studied at our facility. The results of these experiments will be presented.

  13. ACCELERATED SITE TECHNOLOGY DEPLOYMENT COST AND PERFORMANCE REPORT COMPARABILITY OF ISOCS INSTRUMENT IN RADIONUCLIDE CHARACTERICATION AT BROOKHAVEN NATIONAL LABORATORY

    SciTech Connect

    KALB,P.; LUCKETT,L.; MILLER,K.; GOGOLAK,C.; MILIAN,L.

    2001-03-01

    This report describes a DOE Accelerated Site Technology Deployment project being conducted at Brookhaven National Laboratory to deploy innovative, radiological, in situ analytical techniques. The technologies are being deployed in support of efforts to characterize the Brookhaven Graphite Research Reactor (BGRR) facility, which is currently undergoing decontamination and decommissioning. This report focuses on the deployment of the Canberra Industries In Situ Object Counting System (ISOCS) and assesses its data comparability to baseline methods of sampling and laboratory analysis. The battery-operated, field deployable gamma spectrometer provides traditional spectra of counts as a function of gamma energy. The spectra are then converted to radionuclide concentration by applying innovative efficiency calculations using monte carlo statistical methods and pre-defined geometry templates in the analysis software. Measurement of gamma emitting radionuclides has been accomplished during characterization of several BGRR components including the Pile Fan Sump, Above Ground Ducts, contaminated cooling fans, and graphite pile internals. Cs-137 is the predominant gamma-emitting radionuclide identified, with smaller quantities of Co-60 and Am-241 detected. The Project used the Multi-Agency Radiation Survey and Site Investigation Manual guidance and the Data Quality Objectives process to provide direction for survey planning and data quality assessment. Analytical results have been used to calculate data quality indicators (DQI) for the ISOCS measurements. Among the DQIs assessed in the report are sensitivity, accuracy, precision, bias, and minimum detectable concentration. The assessment of the in situ data quality using the DQIs demonstrates that the ISOCS data quality can be comparable to definitive level laboratory analysis when the field instrument is supported by an appropriate Quality Assurance Project Plan. A discussion of the results obtained by ISOCS analysis of

  14. Simulation of Tunable Infra-Red Free-Electron Laser Based on Test Linac of Pohang Accelerator Laboratory

    NASA Astrophysics Data System (ADS)

    Kim, Hyoung Suk; Hahn, Sang June; Lee, Jae Koo

    1993-07-01

    We have investigated the possibility of tunable Infrared Free-Electron Laser with Test Linac of Pohang Accelerator Laboratory through one dimensional simulation which includes energy spread and space charge effects and 3-D particle simulation that ignores space charge force but takes into account the energy spread and the emittance of the electron beam and the diffraction of the electromagnetic wave. The enhanced current density of the Test Linac makes it feasible to amplify the 4.2 kW signal of 10.6 μm radiation to 200 MW level. Extending the design parameters, electron beam energy (20˜60 MeV), wiggler field strength (around 3 kG), and radiation wavelength (10˜90 μm), we have revealed the requisites for the design of the tunable radiation source and the expected gains in that frequency range. It is shown to generate more than 100 MW in the tunable range.

  15. Optical Tagging of Ion Beams Accelerated by Double Layers in Laboratory Plasma

    NASA Astrophysics Data System (ADS)

    Good, Timothy; Aguirre, Evan; Thompson, Derek; Scime, Earl

    2016-10-01

    Experiments in helicon sources that investigate plasma expansion into weakly magnetized, low density regions reveal the production of supersonic ion beams attributed to acceleration by spatially localized double layer structures. Current efforts are aimed at mapping the ion velocity flow field utilizing 2D spatially scanning laser induced fluorescence (LIF) probes that yield metastable ion velocity distribution functions (IVDF) for velocities along and perpendicular to the flow. Observation of metastable ion beams by LIF renders plausible a Lagrangian approach to studying the field-ion interaction via optical tagging. We propose a tagging scheme in which metastable state ion populations are modulated by optical pumping upstream of the double layer and the synchronous detection of LIF at the ion beam velocity is recorded downstream. Besides the unambiguous identification of the source of beam ions, this method can provide detailed dynamical information through time of flight analysis. Preliminary results will be presented. Please include this poster in session that includes poster authored by Evan Aguirre et al.

  16. Prediction and accelerated laboratory discovery of previously unknown 18-electron ABX compounds

    NASA Astrophysics Data System (ADS)

    Gautier, Romain; Zhang, Xiuwen; Hu, Linhua; Yu, Liping; Lin, Yuyuan; Sunde, Tor O. L.; Chon, Danbee; Poeppelmeier, Kenneth R.; Zunger, Alex

    2015-04-01

    Chemists and material scientists have often focused on the properties of previously reported compounds, but neglect numerous unreported but chemically plausible compounds that could have interesting properties. For example, the 18-valence electron ABX family of compounds features examples of topological insulators, thermoelectrics and piezoelectrics, but only 83 out of 483 of these possible compounds have been made. Using first-principles thermodynamics we examined the theoretical stability of the 400 unreported members and predict that 54 should be stable. Of those previously unreported ‘missing’ materials now predicted to be stable, 15 were grown in this study; X-ray studies agreed with the predicted crystal structure in all 15 cases. Among the predicted and characterized properties of the missing compounds are potential transparent conductors, thermoelectric materials and topological semimetals. This integrated process—prediction of functionality in unreported compounds followed by laboratory synthesis and characterization—could be a route to the systematic discovery of hitherto missing, realizable functional materials.

  17. Cracking and delamination behaviors of photovoltaic backsheet after accelerated laboratory weathering

    NASA Astrophysics Data System (ADS)

    Lin, Chiao-Chi; Lyu, Yadong; Hunston, Donald L.; Kim, Jae Hyun; Wan, Kai-Tak; Stanley, Deborah L.; Gu, Xiaohong

    2015-09-01

    The channel crack and delamination phenomena that occurred during tensile tests were utilized to study surface cracking and delamination properties of a multilayered backsheet. A model sample of commercial PPE (polyethylene terephthalate (PET)/PET/ethylene vinyl acetate (EVA)) backsheet was studied. Fragmentation testing was performed after accelerated aging with and without ultraviolet (UV) irradiation in two relative humidity (RH) levels (5 % RH and 60 % RH) at elevated temperature (85 °C) conditions for 11 days and 22 days. Results suggest that the embrittled surface layer resulting from the UV photo-degradation is responsible for surface cracking when the strain applied on the sample is far below the yielding strain (2.2 %) of the PPE sample. There was no surface cracking observed on the un-aged sample and samples aged without UV irradiation. According to the fragmentation testing results, the calculated fracture toughness (KIC) values of the embrittled surface layer are as low as 0.027 MPa·m1/2 to 0.104 MPa·m1/2, depending on the humidity levels and aging times. Surface analysis using attenuated total reflectance Fourier transform infrared and atomic force microscopy shows the degradation mechanism of the embrittled surface layer is a combination of the photodegradation within a certain degradation depth and the moisture erosion effect depending on the moisture levels. Specifically, UV irradiation provides a chemical degradation effect while moisture plays a synergistic effect on surface erosion, which influences surface roughness after aging. Finally, there was no delamination observed during tensile testing in this study, suggesting the surface cracking problem is more significant than the delamination for the PPE backsheet material and conditions tested here.

  18. The André E. Lalonde AMS Laboratory - The new accelerator mass spectrometry facility at the University of Ottawa

    NASA Astrophysics Data System (ADS)

    Kieser, W. E.; Zhao, X.-L.; Clark, I. D.; Cornett, R. J.; Litherland, A. E.; Klein, M.; Mous, D. J. W.; Alary, J.-F.

    2015-10-01

    The University of Ottawa, Canada, has installed a multi-element, 3 MV tandem AMS system as the cornerstone of their new Advanced Research Complex and the principal analytical instrument of the André E. Lalonde Accelerator Mass Spectrometry Laboratory. Manufactured by High Voltage Engineering Europa B.V., the Netherlands, it is equipped with a 200 sample ion source, a high resolution, 120° injection magnet, a 90° high energy analysis magnet (mass-energy product 350 MeV-AMU), a 65°, 1.7 m radius electric analyzer and a 2 channel gas ionization detector. It is designed to analyze isotopes ranging from tritium to the actinides and to accommodate the use of fluoride target materials. This system is being extended with a second injection line, consisting of selected components from the IsoTrace Laboratory, University of Toronto. This line will contain a pre-commercial version of the Isobar Separator for Anions, manufactured by Isobarex Corp., Bolton, Ontario, Canada. This instrument uses selective ion-gas reactions in a radio-frequency quadrupole cell to attenuate both atomic and molecular isobars. This paper discusses the specifications of the new AMS equipment, reports on the acceptance test results for 10Be, 14C, 26Al and 127I and presents typical spectra for 10Be and actinide analyses.

  19. Coupled Mechanical-Electrochemical-Thermal Modeling for Accelerated Design of EV Batteries; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    Pesaran, Ahmad; Zhang, Chao; Kim, Gi-heon; Santhanagopalan, Shriram

    2015-06-10

    The physical and chemical phenomena occurring in a battery are many and complex and in many different scales. Without a better knowledge of the interplay among the multi-physics occurring across the varied scales, it is very challenging and time consuming to design long-lasting, high-performing, safe, affordable large battery systems, enabling electrification of the vehicles and modernization of the grid. The National Renewable Energy Laboratory, a U.S. Department of Energy laboratory, has been developing thermal and electrochemical models for cells and battery packs. Working with software producers, carmakers, and battery developers, computer-aided engineering tools have been developed that can accelerate the electrochemical and thermal design of batteries, reducing time to develop and optimize them and thus reducing the cost of the system. In the past couple of years, we initiated a project to model the mechanical response of batteries to stress, strain, fracture, deformation, puncture, and crush and then link them to electrochemical and thermal models to predict the response of a battery. This modeling is particularly important for understanding the physics and processes that happen in a battery during a crush-inducing vehicle crash. In this paper, we provide an overview of electrochemical-thermal-mechanical models for battery system understanding and designing.

  20. AstroPAL: A Mentoring Program for Grad Students

    NASA Astrophysics Data System (ADS)

    Cabrera, Nicole

    2016-01-01

    The Astronomy Peer Advising Leaders program (AstroPAL) provides guidance for incoming grad students from a team of student volunteers who have passed their 2nd year Qualifier Exam. The purpose is to pair first years with a mentor who can help them through some of the stresses or difficulties that come with being a new grad student. AstroPALs and mentees meet privately about once a month in a casual setting to talk about how they're adjusting to the new surroundings, how they're handling the workload, etc. New students can join AstroPAL at any time during their first two years, and can stop receiving guidance once they feel comfortable in the program. Mentees will be assigned an AstroPAL based on preference and availability, and an AstroPAL Liason will always be in place to facilitate mentor reassignments or other issues if necessary. After passing the 2nd year Qualifier Exam, mentees are eligible to serve as mentors to incoming students.

  1. Molecular Phenotyping of the pal1 and pal2 Mutants of Arabidopsis thaliana Reveals Far-Reaching Consequences on Phenylpropanoid, Amino Acid, and Carbohydrate Metabolism

    PubMed Central

    Rohde, Antje; Morreel, Kris; Ralph, John; Goeminne, Geert; Hostyn, Vanessa; De Rycke, Riet; Kushnir, Sergej; Van Doorsselaere, Jan; Joseleau, Jean-Paul; Vuylsteke, Marnik; Van Driessche, Gonzalez; Van Beeumen, Jozef; Messens, Eric; Boerjan, Wout

    2004-01-01

    The first enzyme of the phenylpropanoid pathway, Phe ammonia-lyase (PAL), is encoded by four genes in Arabidopsis thaliana. Whereas PAL function is well established in various plants, an insight into the functional significance of individual gene family members is lacking. We show that in the absence of clear phenotypic alterations in the Arabidopsis pal1 and pal2 single mutants and with limited phenotypic alterations in the pal1 pal2 double mutant, significant modifications occur in the transcriptome and metabolome of the pal mutants. The disruption of PAL led to transcriptomic adaptation of components of the phenylpropanoid biosynthesis, carbohydrate metabolism, and amino acid metabolism, revealing complex interactions at the level of gene expression between these pathways. Corresponding biochemical changes included a decrease in the three major flavonol glycosides, glycosylated vanillic acid, scopolin, and two novel feruloyl malates coupled to coniferyl alcohol. Moreover, Phe overaccumulated in the double mutant, and the levels of many other amino acids were significantly imbalanced. The lignin content was significantly reduced, and the syringyl/guaiacyl ratio of lignin monomers had increased. Together, from the molecular phenotype, common and specific functions of PAL1 and PAL2 are delineated, and PAL1 is qualified as being more important for the generation of phenylpropanoids. PMID:15377757

  2. Establishment of the Ambient pH Signaling Complex in Aspergillus nidulans: PalI Assists Plasma Membrane Localization of PalH▿

    PubMed Central

    Calcagno-Pizarelli, Ana M.; Negrete-Urtasun, Susana; Denison, Steven H.; Rudnicka, Joanna D.; Bussink, Henk-Jan; Múnera-Huertas, Tatiana; Stanton, Ljiljana; Hervás-Aguilar, América; Espeso, Eduardo A.; Tilburn, Joan; Arst, Herbert N.; Peñalva, Miguel A.

    2007-01-01

    The Aspergillus nidulans ambient pH signaling pathway involves two transmembrane domain (TMD)-containing proteins, PalH and PalI. We provide in silico and mutational evidence suggesting that PalI is a three TMD (3-TMD) protein with an N-terminal signal peptide, and we show that PalI localizes to the plasma membrane. PalI is not essential for the proteolytic conversion of the PacC translation product into the processed 27-kDa form, but its absence markedly reduces the accumulation of the 53-kDa intermediate after cells are shifted to an alkaline pH. PalI and its homologues contain a predicted luminal, conserved Gly-Cys-containing motif that distantly resembles a Gly-rich dimerization domain. The Gly44Arg and Gly47Asp substitutions within this motif lead to loss of function. The Gly47Asp substitution prevents plasma membrane localization of PalI-green fluorescent protein (GFP) and leads to its missorting into the multivesicular body pathway. Overexpression of the likely ambient alkaline pH receptor, the 7-TMD protein PalH, partially suppresses the null palI32 mutation. Although some PalH-GFP localizes to the plasma membrane, it predominates in internal membranes. However, the coexpression of PalI to stoichiometrically similar levels results in the strong predominance of PalH-GFP in the plasma membrane. Thus, one role for PalI, but possibly not the only role, is to assist with plasma membrane localization of PalH. These data, considered along with previous reports for both Saccharomyces cerevisiae and A. nidulans, strongly support the prevailing model of pH signaling involving two spatially segregated complexes: a plasma membrane complex containing PalH, PalI, and the arrestin-like protein PalF and an endosomal membrane complex containing PalA and PalB, to which PacC is recruited for its proteolytic activation. PMID:17951518

  3. Representing Value as Digital Object: A Discussion of Transferability and Anonymity; Digital Library Initiatives of the Deutsche Forschungsgemeinschaft; CrossRef Turns One; Fermi National Accelerator Laboratory (Fermilab).

    ERIC Educational Resources Information Center

    Kahn, Robert E.; Lyons, Patrice A.; Brahms, Ewald; Brand, Amy; van den Bergen, Mieke

    2001-01-01

    Includes four articles that discuss the use of digital objects to represent value in a network environment; digital library initiatives at the central public funding organization for academic research in Germany; an application of the Digital Object Identifier System; and the Web site of the Fermi National Accelerator Laboratory. (LRW)

  4. Do you want to build such a machine? : Designing a high energy proton accelerator for Argonne National Laboratory.

    SciTech Connect

    Paris, E.

    2004-04-05

    Argonne National Laboratory's efforts toward researching, proposing and then building a high-energy proton accelerator have been discussed in a handful of studies. In the main, these have concentrated on the intense maneuvering amongst politicians, universities, government agencies, outside corporations, and laboratory officials to obtain (or block) approval and/or funds or to establish who would have control over budgets and research programs. These ''top-down'' studies are very important but they can also serve to divorce such proceedings from the individuals actually involved in the ground-level research which physically served to create theories, designs, machines, and experiments. This can lead to a skewed picture, on the one hand, of a lack of effect that so-called scientific and technological factors exert and, on the other hand, of the apparent separation of the so-called social or political from the concrete practice of doing physics. An exception to this approach can be found in the proceedings of a conference on ''History of the ZGS'' held at Argonne at the time of the Zero Gradient Synchrotron's decommissioning in 1979. These accounts insert the individuals quite literally as they are, for the most part, personal reminiscences of those who took part in these efforts on the ground level. As such, they are invaluable raw material for historical inquiry but generally lack the rigor and perspective expected in a finished historical work. The session on ''Constructing Cold War Physics'' at the 2002 annual History of Science Society Meeting served to highlight new approaches circulating towards history of science and technology in the post-WWII period, especially in the 1950s. There is new attention towards the effects of training large numbers of scientists and engineers as well as the caution not to equate ''national security'' with military preparedness, but rather more broadly--at certain points--with the explicit ''struggle for the hearts and minds of

  5. Accuracy of activPAL Self-Attachment Methods

    ERIC Educational Resources Information Center

    Kringen, Nina L.; Healy, Genevieve N.; Winkler, Elisabeth A. H.; Clark, Bronwyn K.

    2016-01-01

    This study examined the accuracy of self-attachment of the activPAL activity monitor. A convenience sample of 50 participants self-attached the monitor after being presented with written material only (WMO) and then written and video (WV) instructions; and completed a questionnaire regarding the acceptability of the instructional methods.…

  6. Content Analysis Schedule for Bilingual Education Programs: Proyecto PAL.

    ERIC Educational Resources Information Center

    Gonzalez, Castor

    This content analysis schedule for "Proyecto PAL" in San Jose, California, presents information on the history, funding, and scope of the project. Included are sociolinguistic process variables such as the native and dominant languages of students and their interaction. Information is provided on staff selection and the linguistic…

  7. Peer Assistance and Leadership (PAL) Program. Program Summary.

    ERIC Educational Resources Information Center

    Thomas, H. Grant, Jr.

    This document describes the Peer Assistance and Leadership (PAL) Program, a peer helping program developed by the Austin Independent School District in Austin, Texas. It explains how selected high school students are trained to work as peer facilitators with younger students either on their own campus or from feeder junior high or elementary…

  8. A Pen Pal Project Connects Preservice Teachers and Urban Youth

    ERIC Educational Resources Information Center

    Wilfong, Lori G.; Oberhauser, Casey

    2012-01-01

    This article describes a pen pal project that took place between preservice teachers and students in an urban middle school. The purpose of this project was twofold: to expose preservice teachers to the rewards of urban teaching and to expose urban middle school students to adult reading role models. As a result of the project, both goals were…

  9. Cal-Pal: A County-Wide Volunteer Service Program.

    ERIC Educational Resources Information Center

    Wilson, John; And Others

    1993-01-01

    The implementation and continuing growth of a volunteer youth/adult match-up service, Cal-Pal, being provided in seven rural communities are described in this article. School social workers in these areas can collaborate with other school-based personnel and community leaders to make such a service available. A major benefit of the program is the…

  10. PAL--A Language Designed for Teaching Programming Linguistics.

    ERIC Educational Resources Information Center

    Evans, Arthur, Jr.

    This paper describes PAL--a new computer language. It is used as a pedagogical vehicle in an undergraduate subject called "Programming Linguistics." This subject is designed primarily for sophomores who anticipate a major professional interest in computer science and has two objectives. The first is to study linguistic constructs for the…

  11. Proliferation related acidic leucine-rich protein PAL31 functions as a caspase-3 inhibitor

    SciTech Connect

    Sun Weiyong; Kimura, Hiromichi; Shiota, Kunio . E-mail: ashiota@mail.ecc.u-tokyo.ac.jp

    2006-04-14

    Proliferation related acidic leucine-rich protein PAL31 (PAL31) is expressed in proliferating cells and consists of 272 amino acids with a tandem structure of leucine-rich repeats in the N-terminus and a highly acidic region with a putative nuclear localization signal in the C-terminus. We previously reported that PAL31 is required for cell cycle progression. In the present study, we found that the antisense oligonucleotide of PAL31 induced apoptosis to the transfected Nb2 cells. Stable transfectants, in which PAL31 was regulated by an inducible promoter, were generated to gain further insight into the signaling role of PAL31 in the regulation of apoptosis. Expression of PAL31 resulted in the marked rescue of Rat1 cells from etoposide and UV radiation-induced apoptosis and the cytoprotection was correlated with the levels of PAL31 protein. Thus, cytoprotection from apoptosis is a physiological function of PAL31. PAL31 can suppress caspase-3 activity but not cytochrome c release in vitro, indicating that PAL31 is a direct caspase-3 inhibitor. In conclusion, PAL31 is a multifunctional protein working as a cell cycle progression factor as well as a cell survival factor.

  12. Pen Pal Writing: A Holistic and Socio-Cultural Approach to Adult English Literacy

    ERIC Educational Resources Information Center

    Larrotta, Clarena; Serrano, Arlene F.

    2012-01-01

    This qualitative study reports the findings implementing a pen pal letter exchange project between adult English language learners and volunteer native English speakers. The pen pal project was implemented using a holistic and socio-cultural approach to English literacy development. This article presents pen pal writing as an authentic language…

  13. Progress on plasma accelerators

    SciTech Connect

    Chen, P.

    1986-05-01

    Several plasma accelerator concepts are reviewed, with emphasis on the Plasma Beat Wave Accelerator (PBWA) and the Plasma Wake Field Accelerator (PWFA). Various accelerator physics issues regarding these schemes are discussed, and numerical examples on laboratory scale experiments are given. The efficiency of plasma accelerators is then revealed with suggestions on improvements. Sources that cause emittance growth are discussed briefly.

  14. PALS and DSC study of nanopores partially filled by hexadecane

    NASA Astrophysics Data System (ADS)

    Šauša, O.; Illeková, E.; Krištiak, J.; Berek, D.; Macová, E.

    2013-06-01

    The controlled porosity glasses (CPG) filled with various amount of hexadecane (HXD) in nanopores were studied both by the positron annihilation lifetime spectroscopy (PALS) and the differential scanning calorimetry (DSC) methods. Two types of CPG matrices were used with average pore sizes 12.6 and 22.2 nm. The PALS measurements showed, that when the process of large pores filling by HXD has started, the long o-Ps lifetime went down to HXD o-Ps lifetime about 3ns [1]. DSC measurements at partially filled nanopores showed always two crystallization peaks [2]. Their positions depended on average pore size of matrix. Third crystallization peak was identified in overfilled samples (only short o-Ps lifetimes were present) and their position in temperature scale was the same as for the bulk HXD peak. The latter peak was independent of the average pore size of matrices. This fact confirms the assumption that processes studied by PALS with the samples that contained smaller amount of HXD in CPG occured inside of nanopores of the matrix.

  15. PAL inhibitor evokes different responses in two Hypericum species.

    PubMed

    Klejdus, Bořivoj; Kováčik, Jozef; Babula, Petr

    2013-02-01

    Accumulation of secondary metabolites (general phenols, naphthodianthrones and phloroglucinol hyperforin) in Hypericum perforatum and Hypericum canariense after application of the inhibitor (2-aminoindane-2-phosphonic acid, AIP) of the pivotal enzyme of general phenylpropanoid pathway (phenylalanine ammonia-lyase, PAL) was studied. Shoots of H. perforatum revealed more expressive growth depression, concomitantly with the inhibition of PAL activity (-60%) and decrease in soluble phenols and individual phenolic acids in response to AIP. Hypericins (hypericin, pseudohypericin and protohypericin) decreased while hyperforin increased in AIP-cultured H. perforatum. On the contrary, growth changes, decreases in soluble phenols and individual phenolic acids were less-visible in H. canariense. This was also reflected in restoration of PAL activity (+330%) and selected flavonoids even increased. Hypericins and hyperforin were present in several orders of magnitude lower amounts in comparison with H. perforatum. Increase in proline indicates potential compensatory antioxidative mechanism if phenols are depleted. Microscopy revealed also differences in secondary xylem formation and lignification between species after exposure to AIP.

  16. PAL: an object-oriented programming library for molecular evolution and phylogenetics.

    PubMed

    Drummond, A; Strimmer, K

    2001-07-01

    Phylogenetic Analysis Library (PAL) is a collection of Java classes for use in molecular evolution and phylogenetics. PAL provides a modular environment for the rapid construction of both special-purpose and general analysis programs. PAL version 1.1 consists of 145 public classes or interfaces in 13 packages, including classes for models of character evolution, maximum-likelihood estimation, and the coalescent, with a total of more than 27000 lines of code. The PAL project is set up as a collaborative project to facilitate contributions from other researchers. AVAILIABILTY: The program is free and is available at http://www.pal-project.org. It requires Java 1.1 or later. PAL is licensed under the GNU General Public License.

  17. Overview of the Standing Operating Procedures (SOP) for the Development of Provisional Advisory Levels (PALs)

    SciTech Connect

    Young, Robert; Bast, Cheryl B; Wood, Carol S; Adeshina, Femi; Ross, Robert Hord

    2009-01-01

    Provisional Advisory Levels (PALs) are concentrations in air and drinking water for priority toxic chemicals. This article summarizes the Standing Operating Procedures (SOPs) currently in place for the data-driven development of chemical-specific PALs. To provide consistency and transparency, and to avoid faults of arbitrariness, SOPs were developed for guidance in deriving PAL values. The SOPs for PAL development focus on: 1) data acquisition and analysis, 2) identification of a chemical-specific critical effect, 3) selection of a quantitative point-of-departure (POD), 4) uncertainty analysis and adjustments, 5) exposure duration adjustment and extrapolation, 6) identification of special concerns and issues, and 7) verification, documentation and dissemination of PALs. To avoid uncompromising rigidity in deriving PAL values and to allow for incorporation of new or refined methodologies, the overall procedure is fluid and subject to modification. The purpose of this publication is to provide a summary of these SOPs.

  18. 4-H PetPALS Juvenile Diversion Program Supports At-Risk Youth and Seniors

    ERIC Educational Resources Information Center

    Goble, Connie L.; Miller, Lucinda B.

    2014-01-01

    The 4-H PetPALS Juvenile Diversion Program provides a partnership opportunity with Extension and the juvenile court system to positively impact lives of at-risk youth. At-risk youth are taught by 4-H PetPALS adult volunteer leaders and 4-H PetPALS members to value and respect the human-animal bond, as well as to understand and empathize with…

  19. Production and isolation of homologs of flerovium and element 115 at the Lawrence Livermore National Laboratory Center for Accelerator Mass Spectrometry

    SciTech Connect

    Despotopulos, John D.; Kmak, Kelly N.; Gharibyan, Narek; Brown, Thomas A.; Grant, Patrick M.; Henderson, Roger A.; Moody, Kent J.; Tumey, Scott J.; Shaughnessy, Dawn A.; Sudowe, Ralf

    2015-10-01

    Here, new procedures have been developed to isolate no-carrier-added (NCA) radionuclides of the homologs and pseudo-homologs of flerovium (Hg, Sn) and element 115 (Sb), produced by 12–15 MeV proton irradiation of foil stacks with the tandem Van-de-Graaff accelerator at the Lawrence Livermore National Laboratory Center for Accelerator Mass Spectrometry (CAMS) facility. The separation of 113Sn from natIn foil was performed with anion-exchange chromatography from hydrochloric and nitric acid matrices. A cation-exchange chromatography method based on hydrochloric and mixed hydrochloric/hydroiodic acids was used to separate 124Sb from natSn foil. A procedure using Eichrom TEVA resin was developed to separate 197Hg from Au foil. These results demonstrate the suitability of using the CAMS facility to produce NCA radioisotopes for studies of transactinide homologs.

  20. Production and isolation of homologs of flerovium and element 115 at the Lawrence Livermore National Laboratory Center for Accelerator Mass Spectrometry

    DOE PAGES

    Despotopulos, John D.; Kmak, Kelly N.; Gharibyan, Narek; ...

    2015-10-01

    Here, new procedures have been developed to isolate no-carrier-added (NCA) radionuclides of the homologs and pseudo-homologs of flerovium (Hg, Sn) and element 115 (Sb), produced by 12–15 MeV proton irradiation of foil stacks with the tandem Van-de-Graaff accelerator at the Lawrence Livermore National Laboratory Center for Accelerator Mass Spectrometry (CAMS) facility. The separation of 113Sn from natIn foil was performed with anion-exchange chromatography from hydrochloric and nitric acid matrices. A cation-exchange chromatography method based on hydrochloric and mixed hydrochloric/hydroiodic acids was used to separate 124Sb from natSn foil. A procedure using Eichrom TEVA resin was developed to separate 197Hg frommore » Au foil. These results demonstrate the suitability of using the CAMS facility to produce NCA radioisotopes for studies of transactinide homologs.« less

  1. Overview of the Standing Operating Procedure (SOP) for the development of Provisional Advisory Levels (PALs).

    PubMed

    Young, Robert A; Bast, Cheryl B; Wood, Carol S; Adeshina, Femi

    2009-12-01

    Provisional Advisory Levels (PALs) are concentrations in air and drinking water for priority toxic chemicals. This article summarizes the Standing Operating Procedure (SOP) currently in place for the data-driven development of chemical-specific PALs. To provide consistency and transparency, and to avoid faults of arbitrariness, the SOP was developed for guidance in deriving PAL values. Three levels (PAL 1, PAL 2, and PAL 3), distinguished by severity of toxic effects, are developed for 24-hour, 30-day, 90-day, and 2-year durations of potential drinking water and inhalation exposures for the general public. The SOP for PAL development focuses on (1) data acquisition and analysis, (2) identification of a chemical-specific critical effect, (3) selection of a quantitative point-of-departure (POD), (4) uncertainty analysis and adjustments, (5) exposure duration adjustment and extrapolation, (6) identification of special concerns and issues, and (7) verification, documentation, and dissemination of PALs. To avoid uncompromising rigidity in deriving PAL values and to allow for incorporation of new or refined methodologies, the overall procedure is fluid and subject to modification. The purpose of this publication is to provide a summary of this SOP.

  2. Magnetostriction and palæomagnetism of igneous rocks

    USGS Publications Warehouse

    Graham, John W.; Buddington, A.F.; Balsley, James R.

    1959-01-01

    IN a recent communication, Stott and Stacey1 report on a “crucial experiment” from which they conclude: “This excellent agreement between the dip and the directions of artificial thermoremanent magnetization of the stressed and unstressed rocks indicates that large systematic errors due to magnetostriction are most improbable in igneous rocks of types normally used for palæomagnetic work”. This experiment was intended to test the proposals2 and measurements3 bearing on the role of magnetostriction in rock magnetism. We present here our reasons for believing that the experiment was not crucial and that the conclusion is not justified.

  3. World Pendulum--A Distributed Remotely Controlled Laboratory (RCL) to Measure the Earth's Gravitational Acceleration Depending on Geographical Latitude

    ERIC Educational Resources Information Center

    Grober, S.; Vetter, M.; Eckert, B.; Jodl, H.-J.

    2007-01-01

    We suggest that different string pendulums are positioned at different locations on Earth and measure at each place the gravitational acceleration (accuracy [delta]g is approximately equal to 0.01 m s[superscript -2]). Each pendulum can be remotely controlled via the internet by a computer located somewhere on Earth. The theoretical part describes…

  4. Report on Proton and Ion Beam measurements at the Matter in Extreme Condition (MCC) end station at SLAC National Accelerator Laboratory

    SciTech Connect

    Gauthier, Maxence

    2016-02-16

    We report on MeV ion beams produced with high-repetition rates of 1 Hz at the MEC end station at SLAC National Accelerator Laboratory. These data were obtained during the commissioning beam time of the new 30TW laser. After describing the experimental set-up, the laser conditions and the target diagnostics, ion beam spectra measured for different foil thicknesses and laser intensities will be presented and discussed. These results are subsequently compared with results from cryogenic hydrogen jets at MEC in January 2015.

  5. Accelerating Ocean Energy to the Marketplace – Environmental Research at the U.S. Department of Energy National Laboratories

    SciTech Connect

    Copping, Andrea E.; Cada, G. F.; Roberts, Jesse; Bevelhimer, Mark

    2010-10-06

    The U.S. Department of Energy (US DOE) has mobilized its National Laboratories to address the broad range of environmental effects of ocean and river energy development. The National Laboratories are using a risk-based approach to set priorities among environmental effects, and to direct research activities. Case studies will be constructed to determine the most significant environmental effects of ocean energy harvest for tidal systems in temperate estuaries, for wave energy installations in temperate coastal areas, wave installations in sub-tropical waters, and riverine energy installations in large rivers. In addition, the National Laboratories are investigating the effects of energy removal from waves, tides and river currents using numerical modeling studies. Laboratory and field research is also underway to understand the effects of electromagnetic fields (EMF), acoustic noise, toxicity from anti-biofouling coatings, effects on benthic habitats, and physical interactions with tidal and wave devices on marine and freshwater organisms and ecosystems. Outreach and interactions with stakeholders allow the National Laboratories to understand and mitigate for use conflicts and to provide useful information for marine spatial planning at the national and regional level.

  6. Statistical correlation of the soil incubation and the accelerated laboratory extraction methods to estimate nitrogen release rates of slow- and controlled-release fertilizers.

    PubMed

    Medina, L Carolina; Sartain, Jerry; Obreza, Thomas; Leary, Emily; Hall, William L; Thiex, Nancy J

    2014-01-01

    Several technologies have been proposed to characterize the nutrient release patterns of enhanced-efficiency fertilizers (EEFs) during the last few decades. These technologies have been developed mainly by manufacturers and are product-specific based on the regulation and analysis of each EEF product. Despite previous efforts to characterize nutrient release of slow-release fertilizer (SRF) and controlled-release fertilizer (CRF) materials, no official method exists to assess their nutrient release patterns. However, the increased production and distribution of EEFs in specialty and nonspecialty markets requires an appropriate method to verify nutrient claims and material performance. Nonlinear regression was used to establish a correlation between the data generated from a 180-day soil incubation-column leaching procedure and 74 h accelerated lab extraction method, and to develop a model that can predict the 180-day nitrogen (N) release curve for a specific SRF and CRF product based on the data from the accelerated laboratory extraction method. Based on the R2 > 0.90 obtained for most materials, results indicated that the data generated from the 74 h accelerated lab extraction method could be used to predict N release from the selected materials during 180 days, including those fertilizers that require biological activity for N release.

  7. Planned Alternation of Languages (PAL): Language Use and Distribution in Bilingual Classrooms.

    ERIC Educational Resources Information Center

    Romero, Migdalia; Parrino, Angela

    1994-01-01

    Following a brief discussion of legal and academic statements on mandatory bilingual education and mainstreaming, three models of the Planned Alternation of Languages (PAL) approach are described as a way to prepare students for mainstreaming. PAL allows for both languages to have feasible functions and support learners through acquisition of…

  8. Getting to Know You: Cross-Cultural Pen Pals Expand Children's World View

    ERIC Educational Resources Information Center

    Shandomo, Hibajene M.

    2009-01-01

    In this article, the author described the Poplar Street-Naledi pen pal project. The goals of this project were to provide elementary school students with a broader view of the world, to increase their social and cultural awareness, to develop content knowledge of where their pen pals live, and to determine the impact of this project on student…

  9. "Aloha", Hoosier! A Pen-Pal Activity in the Third Grade

    ERIC Educational Resources Information Center

    Callahan, Raymond; Chan, Kam Chi

    2007-01-01

    Ray, a preservice teacher in Indiana, and Maxine, a 35-year teaching veteran in Hawai'i, set up a pen-pal program for the third grade students in their respective classrooms, 4,000 miles apart. This pen-pal program, used in conjunction with children's literature and community and technology resources, brought about memorable learning experiences.…

  10. Validation of Goal Orientation Measure in PALS among Latino Adolescents Participating in a College Outreach Program

    ERIC Educational Resources Information Center

    Rinthapol, Nida; Duran, Richard

    2011-01-01

    The study will incorporate psychometric methods to examine the validity and reliability of the GO (goal orientation) measure which called PALS (pattern of adaptive learning survey) among immigrant youth. Previous research has not focused on the reliability and validity of the PALS for using with Latino students. Internal consistency reliability…

  11. Stimulant Drug Effects on Touchscreen Automated Paired-Associates Learning (PAL) in Rats

    ERIC Educational Resources Information Center

    Roschlau, Corinna; Votteler, Angeline; Hauber, Wolfgang

    2016-01-01

    Here we tested in rats effects of the procognitive drugs modafinil and methylphenidate on post-acquisition performance in an object-location paired-associates learning (PAL) task. Modafinil (32; 64 mg/kg) was without effect, while higher (9 mg/kg) but not lower (4.5 mg/kg) doses of methylphenidate impaired PAL performance. Likewise, higher but not…

  12. The erosion of the beaches on the coast of Alicante: Study of the mechanisms of weathering by accelerated laboratory tests.

    PubMed

    López, I; López, M; Aragonés, L; García-Barba, J; López, M P; Sánchez, I

    2016-10-01

    One of the main problems that coasts around the world present, is the regression and erosion of beaches. However, the factors involved in these processes are unclear. In this study, the influence of sediment erosion on beach regression has been analysed. In order to do that, a three-step investigation has been carried out. Firstly, coastline variations of four Spanish beaches have been analysed. Secondly, a study on sediment position along the beach profile has been developed. Finally, the process that beach sediments undergo along the surf zone when they are hit by the incident waves has been simulated by an accelerated particle weathering test. Samples of sand and shells were subjected to this accelerated particle weathering test. Results were supplemented with those from carbonate content test, XRD, SEM and granulometric analysis. Results shows a cross-shore classification of sediments along the beach profile in which finer particles move beyond offshore limit. Besides, it was observed that sediment erosion process is divided into three sages: i) particles wear due to crashes ii) dissolution of the carbonate fraction, and iii) breakage and separation of mineral and carbonate parts of particles. All these processes lead to a reduction of particle size. The mechanism responsible of beach erosion would consist of multiples and continuous particle location exchanges along the beach profile as a consequence of grain-size decrease due to erosion.

  13. The Shape of the Inner Milky Way Halo from Observations of the Pal 5 and GD--1 Stellar Streams

    NASA Astrophysics Data System (ADS)

    Bovy, Jo; Bahmanyar, Anita; Fritz, Tobias K.; Kallivayalil, Nitya

    2016-12-01

    We constrain the shape of the Milky Way’s halo by dynamical modeling of the observed phase-space tracks of the Pal 5 and GD-1 tidal streams. We find that the only information about the potential gleaned from the tracks of these streams are precise measurements of the shape of the gravitational potential—the ratio of vertical to radial acceleration—at the location of the streams, with weaker constraints on the radial and vertical accelerations separately. The latter will improve significantly with precise proper-motion measurements from Gaia. We measure that the overall potential flattening is 0.95 ± 0.04 at the location of GD-1 ([R,Z]≈ [12.5,6.7] {kpc}) and 0.94 ± 0.05 at the position of Pal 5 ([R,Z]≈ [8.4,16.8] {kpc}). Combined with constraints on the force field near the Galactic disk, we determine that the axis ratio of the dark-matter halo’s density distribution is 1.05 ± 0.14 within the inner 20 kpc, with a hint that the halo becomes more flattened near the edge of this volume. The halo mass within 20 {kpc} is (1.1+/- 0.1)× {10}11 {M}⊙ . A dark-matter halo this close to spherical is in tension with the predictions from numerical simulations of the formation of dark-matter halos.

  14. [Positron annihilation lifetime spectrometry (PALS) and its pharmaceutical applications].

    PubMed

    Sebe, István; Szabó, Barnabás; Zelkó, Romána

    2012-01-01

    PALS is one of the most widely used "nuclear probe" techniques for the tracking of the structural characteristics of materials. The method is based on the matter-energy equivalence principle recognized by Einstein: the electrons and positrons as particle-antiparticle pairs disappear in mutual destruction of particles, they annihilate with high-energy gamma-radiation, thus "particle-energy transition" occurs. The properties of the resulting radiation exactly correspond to the relevant properties of the electron and positron preceding the annihilation. Since electrons occur in all types of materials, the phenomenon of positron annihilation can play in any environment; consequently the method can be used for the analysis of each type of materials (crystalline and amorphous, organic and inorganic, biotic and abiotic). The present paper provides an overview of the theoretical physical background, the practical realization and evaluation of methods, their limitations, and summarizes the pharmaceutical applications published in recent years.

  15. Cytoprotective and anti-inflammatory effects of PAL31 overexpression in glial cells

    PubMed Central

    2014-01-01

    Background Acute spinal cord injury (SCI) leads to a series of reactive changes and causes severe neurological deficits. A pronounced inflammation contributes to secondary pathology after SCI. Astroglia respond to SCI by proliferating, migrating, and altering phenotype. The impact of reactive gliosis on the pathogenesis of SCI is not fully understood. Our previous study has identified an inflammatory modulating protein, proliferation related acidic leucine-rich protein (PAL31) which is upregulated in the microglia/macrophage of injured cords. Because PAL31 participates in cell cycle progression and reactive astroglia often appears in the injured cord, we aim to examine whether PAL31 is involved in glial modulation after injury. Results Enhanced PAL31 expression was shown not only in microglia/macrophages but also in spinal astroglia after SCI. Cell culture study reveal that overexpression of PAL31 in mixed glial cells or in C6 astroglia significantly reduced LPS/IFNγ stimulation. Further, enhanced PAL31 expression in C6 astroglia protected cells from H2O2 toxicity; however, this did not affect its proliferative activity. The inhibiting effect of PAL31 on LPS/IFNγ stimulation was observed in glia or C6 after co-culture with neuronal cells. The results demonstrated that the overexpressed PAL31 in glial cells protected neuronal damages through inhibiting NF-kB signaling and iNOS. Conclusions Our data suggest that PAL31upregulation might be beneficial after spinal cord injury. Reactive gliosis might become a good target for future therapeutic interventions. PMID:25034417

  16. Characterisation of the willow phenylalanine ammonia-lyase (PAL) gene family reveals expression differences compared with poplar

    PubMed Central

    de Jong, Femke; Hanley, Steven J.; Beale, Michael H.; Karp, Angela

    2015-01-01

    Willow is an important biomass crop for the bioenergy industry, and therefore optimal growth with minimal effects of biotic and abiotic stress is essential. The phenylpropanoid pathway is responsible for the biosynthesis of not only lignin but also of flavonoids, condensed tannins, benzenoids and phenolic glycosides which all have a role in protecting the plant against biotic and abiotic stress. All products of the phenylpropanoid pathway are important for the healthy growth of short rotation cropping species such as willow. However, the phenylpropanoid pathway in willow remains largely uncharacterised. In the current study we identified and characterised five willow phenylalanine ammonia-lyase (PAL) genes, which encode enzymes that catalyse the deamination of l-phenylalanine to form trans-cinnamic acid, the entry point into the phenylpropanoid pathway. Willow PAL1, PAL2, PAL3 and PAL4 genes were orthologous to the poplar genes. However no orthologue of PAL5 appears to be present in willow. Moreover, two tandemly repeated PAL2 orthologues were identified in a single contig. Willow PALs show similar sub-cellular localisation to the poplar genes. However, the enzyme kinetics and gene expression of the willow PAL genes differed slightly, with willow PAL2 being more widely expressed than its poplar orthologues implying a wider role for PALs in the production of flavonoids, condensed tannins, benzenoids, and phenolic glycosides, in willow. PMID:26070140

  17. Characterisation of the willow phenylalanine ammonia-lyase (PAL) gene family reveals expression differences compared with poplar.

    PubMed

    de Jong, Femke; Hanley, Steven J; Beale, Michael H; Karp, Angela

    2015-09-01

    Willow is an important biomass crop for the bioenergy industry, and therefore optimal growth with minimal effects of biotic and abiotic stress is essential. The phenylpropanoid pathway is responsible for the biosynthesis of not only lignin but also of flavonoids, condensed tannins, benzenoids and phenolic glycosides which all have a role in protecting the plant against biotic and abiotic stress. All products of the phenylpropanoid pathway are important for the healthy growth of short rotation cropping species such as willow. However, the phenylpropanoid pathway in willow remains largely uncharacterised. In the current study we identified and characterised five willow phenylalanine ammonia-lyase (PAL) genes, which encode enzymes that catalyse the deamination of l-phenylalanine to form trans-cinnamic acid, the entry point into the phenylpropanoid pathway. Willow PAL1, PAL2, PAL3 and PAL4 genes were orthologous to the poplar genes. However no orthologue of PAL5 appears to be present in willow. Moreover, two tandemly repeated PAL2 orthologues were identified in a single contig. Willow PALs show similar sub-cellular localisation to the poplar genes. However, the enzyme kinetics and gene expression of the willow PAL genes differed slightly, with willow PAL2 being more widely expressed than its poplar orthologues implying a wider role for PALs in the production of flavonoids, condensed tannins, benzenoids, and phenolic glycosides, in willow.

  18. Pal 12 - A metal-rich globular cluster in the outer halo

    NASA Technical Reports Server (NTRS)

    Cohen, J. G.; Frogel, J. A.; Persson, S. E.; Zinn, R.

    1980-01-01

    New optical and infrared observations of several stars in the distant globular cluster Pal 12 show that they have CO strengths and heavy element abundances only slightly less than in M 71, one of the more metal-rich globular clusters. Pal 12 thus has a metal abundance near the high end of the range over which globular clusters exist and lies in the outer galactic halo. Its red horizontal branch is not anomalous in view of the abundance that has been found.

  19. Accelerating the Whiteshell Laboratories Decommissioning Through the Implementation of a Projectized and Delivery-Focused Organization - 13074

    SciTech Connect

    Wilcox, Brian; Mellor, Russ; Michaluk, Craig

    2013-07-01

    Whiteshell Laboratories (WL) is a nuclear research site in Canada that was commissioned in 1964 by Atomic Energy of Canada Limited. It covers a total area of approximately 4,375 hectares (10,800 acres) and includes the main campus site, the Waste Management Area (WMA) and outer areas of land identified as not used for or impacted by nuclear development or operations. The WL site employed up to 1100 staff. Site activities included the successful operation of a 60 MW organic liquid-cooled research reactor from 1965 to 1985, and various research programs including reactor safety research, small reactor development, fuel development, biophysics and radiation applications, as well as work under the Canadian Nuclear Fuel Waste Management Program. In 1997, AECL made a business decision to discontinue research programs and operations at WL, and obtained government concurrence in 1998. The Nuclear Legacy Liabilities Program (NLLP) was established in 2006 by the Canadian Government to remediate nuclear legacy liabilities in a safe and cost effective manner, including the WL site. The NLLP is being implemented by AECL under the governance of a Natural Resources Canada (NRCan)/AECL Joint Oversight Committee (JOC). Significant progress has since been made, and the WL site currently holds the only Canadian Nuclear Safety Commission (CNSC) nuclear research site decommissioning license in Canada. The current decommissioning license is in place until the end of 2018. The present schedule planned for main campus decommissioning is 30 years (to 2037), followed by institutional control of the WMA until a National plan is implemented for the long-term management of nuclear waste. There is an impetus to advance work and complete decommissioning sooner. To accomplish this, AECL has added significant resources, reorganized and moved to a projectized environment. This presentation outlines changes made to the organization, the tools implemented to foster projectization, and the benefits

  20. Characterisation of metakaolin-based geopolymers using beam-based and conventional PALS

    NASA Astrophysics Data System (ADS)

    Guagliardo, P.; Roberts, J.; Vance, E. R.; Weed, R.; Sergeant, A. D.; Howie, A.; Wilkie, P.; Went, M.; Sullivan, J.; Williams, J.; Samarin, S.; Buckman, S.

    2011-01-01

    The nano-porosity of metakaolin-based geopolymers and the effect of heat-treatment on porosity have been studied with conventional and beam-based positron annihilation lifetime spectroscopy (PALS). Conventional PALS found significant nano-porosity in the geopolymers, as indicated by the presence in the PALS spectrum of two long lifetime components, τ3 = 1.58 ns and τ4 = 47 ns, associated with pore diameters of approximately 0.5 and 3 nm respectively. The lifetime of the shorter component was found to decrease monotonically with successive heat treatments of 300°C and 600°C. Beam-based PALS, conducted at 5 keV, also indicated two long lifetime components, τ3 = 4.84 ns and τ4 = 54.6 ns. These are significantly longer than those observed by conventional PALS and the monotonic decrease of τ3 with successive heat treatments was not observed. As the beam-based PALS probed only the near-surface region, with an average implantation depth of about 350 nm, these results suggest that the near-surface structure may vary significantly from that of the bulk. This could be an inherent property of the samples or an artefact caused by surface effects or sample outgassing.

  1. VE-cadherin interacts with cell polarity protein Pals1 to regulate vascular lumen formation.

    PubMed

    Brinkmann, Benjamin F; Steinbacher, Tim; Hartmann, Christian; Kummer, Daniel; Pajonczyk, Denise; Mirzapourshafiyi, Fatemeh; Nakayama, Masanori; Weide, Thomas; Gerke, Volker; Ebnet, Klaus

    2016-09-15

    Blood vessel tubulogenesis requires the formation of stable cell-to-cell contacts and the establishment of apicobasal polarity of vascular endothelial cells. Cell polarity is regulated by highly conserved cell polarity protein complexes such as the Par3-aPKC-Par6 complex and the CRB3-Pals1-PATJ complex, which are expressed by many different cell types and regulate various aspects of cell polarity. Here we describe a functional interaction of VE-cadherin with the cell polarity protein Pals1. Pals1 directly interacts with VE-cadherin through a membrane-proximal motif in the cytoplasmic domain of VE-cadherin. VE-cadherin clusters Pals1 at cell-cell junctions. Mutating the Pals1-binding motif in VE-cadherin abrogates the ability of VE-cadherin to regulate apicobasal polarity and vascular lumen formation. In a similar way, deletion of the Par3-binding motif at the C-terminus of VE-cadherin impairs apicobasal polarity and vascular lumen formation. Our findings indicate that the biological activity of VE-cadherin in regulating endothelial polarity and vascular lumen formation is mediated through its interaction with the two cell polarity proteins Pals1 and Par3.

  2. VE-cadherin interacts with cell polarity protein Pals1 to regulate vascular lumen formation

    PubMed Central

    Brinkmann, Benjamin F.; Steinbacher, Tim; Hartmann, Christian; Kummer, Daniel; Pajonczyk, Denise; Mirzapourshafiyi, Fatemeh; Nakayama, Masanori; Weide, Thomas; Gerke, Volker; Ebnet, Klaus

    2016-01-01

    Blood vessel tubulogenesis requires the formation of stable cell-to-cell contacts and the establishment of apicobasal polarity of vascular endothelial cells. Cell polarity is regulated by highly conserved cell polarity protein complexes such as the Par3-aPKC-Par6 complex and the CRB3-Pals1-PATJ complex, which are expressed by many different cell types and regulate various aspects of cell polarity. Here we describe a functional interaction of VE-cadherin with the cell polarity protein Pals1. Pals1 directly interacts with VE-cadherin through a membrane-proximal motif in the cytoplasmic domain of VE-cadherin. VE-cadherin clusters Pals1 at cell–cell junctions. Mutating the Pals1-binding motif in VE-cadherin abrogates the ability of VE-cadherin to regulate apicobasal polarity and vascular lumen formation. In a similar way, deletion of the Par3-binding motif at the C-terminus of VE-cadherin impairs apicobasal polarity and vascular lumen formation. Our findings indicate that the biological activity of VE-cadherin in regulating endothelial polarity and vascular lumen formation is mediated through its interaction with the two cell polarity proteins Pals1 and Par3. PMID:27466317

  3. Role of DC Electric Fields and Wave Heating in Cavity Profiles of Depleted Density and Transverse Ion Acceleration in Laboratory and Space Plasmas

    NASA Astrophysics Data System (ADS)

    Koepke, M. E.; Reynolds, E. W.; Knudsen, D. J.

    2007-05-01

    Laboratory experiments on the WVU Q Machine, test-particle simulations, and Monte Carlo simulations are shown to provide evidence for explaining the inhomogeneity in both the plasma-density profile and the ion- temperature profile associated with cylindrically symmetric lower-hybrid cavities observed by the GEODESIC sounding rocket, the OEDIPUS-C sounding rocket, and the Freja satellite. Two potential contributions to the inhomogeneous profiles are identified. Both mechanisms (one dc and the other ac) rely on finite values of the Larmor radius and can result in nonlocal effects that deplete ion density within the cavity and enhance ion density immediately outside the cavity to form ion-gyroradius-scale shoulders encircling the cavity perimeter. In the absence of waves, a cylindrically symmetric, radial, DC electric field can be responsible for a polarization shift that produces such inhomogeneity in the density profile [1]. In the presence of waves, wave-induced transverse ion acceleration occurring within the cavity can produce such inhomogeneity in the density profile [2]. In combination, the two effects are shown to be comparable, necessitating an interpretation that includes both mechanisms for quantitative agreement. For the lab data, laser-induced fluorescence techniques provide high resolution in coordinate space and velocity space. [1] Reynolds et al., Inhomogeneity scale lengths in a magnetized, low temperature, collisionless, Q-machine plasma column containing perpendicular-velocity shear, Phys. Plasmas 13, 092106 (2006). [2] Knudsen et al., Lower-hybrid cavity density depletions as a result of transverse ion acceleration localized on the gyroradius scale, J. Geophys. Res. 109, A04212 (2004). This research is supported by NSF.

  4. The PAL1 gene product is a peroxisomal ATP-binding cassette transporter in the yeast Saccharomyces cerevisiae

    PubMed Central

    1996-01-01

    The PAL1 gene was isolated using PCR and degenerate oligonucleotide primers corresponding to highly conserved amino acid sequence motifs diagnostic of the ATP-binding cassette domain of the superfamily of membrane-bound transport proteins typified by mammalian multidrug resistance transporter 1 and Saccharomyces cerevisiae Ste6. The deduced PAL1 gene product is similar in length to, has the same predicted topology as, and shares the highest degree of amino acid sequence identity with two human proteins, adrenoleukodystrophy protein and peroxisomal membrane protein (70 kD), which are both presumptive ATP- binding cassette transporters thought to be constituents of the peroxisomal membrane. As judged by hybridization of a PAL1 probe to isolated RNA and by expression of a PAL1-lacZ fusion, a PAL1 transcript was only detectable when cells were grown on oleic acid, a carbon source which requires the biogenesis of functional peroxisomes for its metabolism. A pal1delta mutant grew normally on either glucose- or glycerol-containing media; however, unlike PAL1+ cells (or the pal1delta mutant carrying the PAL1 gene on a plasmid), pal1delta cells were unable to grow on either a solid medium or a liquid medium containing oleic acid as the sole carbon source. Antibodies raised against a chimeric protein in which the COOH-terminal domain of Pal1 was fused to glutathione S-transferase specifically recognized a protein in extracts from wild-type cells only when grown on oleic acid; this species represents the PAL1 gene product because it was missing in pal1delta cells and more abundant in pal1delta cells expressing PAL1 from a multicopy plasmid. The Pal1 polypeptide was highly enriched in the organellar pellet fraction prepared from wild-type cells by differential centrifugation and comigrated upon velocity sedimentation in a Nycodenz gradient with a known component of the peroxisomal matrix, e-oxoacyl-CoA thiolase. As judged by both subcellular fractionation and indirect

  5. Tertiary ostracods of Gebel Withr, southwestern Sinai, Egypt: pal˦ontology, biostratigraphy and pal˦obiogeography

    NASA Astrophysics Data System (ADS)

    Shahin, A.

    2000-08-01

    The exposed Early Eocene-Early Miocene interval in the study area yields considerable amounts of ostracods. A detailed investigation of the ostracod content has led to the recognition of 79 species and subspecies, five of which are reported as new species. They are Semicytherura bassiounii, Semicytherura gammudii, Pterygocythere withrensis, Paracosta reymenti and Cativella bulgi. An attempt to reconstruct a local ostracod biozonation has led to the recognition of six biostratigraphical zones. These biozones are arranged from the youngest to the oldest as follows: Leguminocythereis bopaensis-Leguminocythereis bicostata Assemblage Zone; Reticulina saitoi-Trachyleberis nodosus Assemblage Zone; Asymmetricythere yousefi-Cytherella piacabucuensis Assemblage Zone; Leguminocythereis africana-Buntonia faresi Assenblage Zone; and Grinioneis haidingeri-Pokornyella deformis minor Assemblage Zone. The palaeobathymetric estimates for these assemblages reveals a great deal from the inner neritic to the upper bathyal environments. The cosmopolitan distribution of the recorded species proved to be useful for pal˦obiogeographic reconstruction. This reveals that there was a direct connection throughout the Tethyan realm and a connection between the Tethyan North Africa and West Africa via the Trans-Saharan Seaway, at least until the end of the Palaeocene, through which the migration of benthic organisms had occurred.

  6. Calculation of Transactinide Homolog Isotope Production Reactions Possible with the Center for Accelerator Mass Spectrometry (CAMS) at Lawrence Livermore National Laboratory

    SciTech Connect

    Moody, K J; Shaughnessy, D A; Gostic, J M

    2011-11-29

    The LLNL heavy element group has been investigating the chemical properties of the heaviest elements over the past several years. The properties of the transactinides (elements with Z > 103) are often unknown due to their low production rates and short half-lives, which require lengthy cyclotron irradiations in order to make enough atoms for statistically significant evaluations of their chemistry. In addition, automated chemical methods are often required to perform consistent and rapid chemical separations on the order of minutes for the duration of the experiment, which can last from weeks to months. Separation methods can include extraction chromatography, liquid-liquid extraction, or gas-phase chromatography. Before a lengthy transactinide experiment can be performed at an accelerator, a large amount of preparatory work must be done both to ensure the successful application of the chosen chemical system to the transactinide chemistry problem being addressed, and to evaluate the behavior of the lighter elemental homologs in the same chemical system. Since transactinide chemistry is literally performed on one single atom, its chemical properties cannot be determined from bulk chemical matrices, but instead must be inferred from the behavior of the lighter elements that occur in its chemical group and in those of its neighboring elements. By first studying the lighter group homologs in a particular chemical system, when the same system is applied to the transactinide element under investigation, its decay properties can be directly compared to those of the homologues, thereby allowing an inference of its own chemistry. The Center for Accelerator Mass Spectrometry (CAMS) at Lawrence Livermore National Laboratory (LLNL) includes a 1 MV Tandem accelerator, capable of accelerating light ions such as protons to energies of roughly 15 MeV. By using the CAMS beamline, tracers of transactinide homolog elements can be produced both for development of chemical systems and

  7. Accelerator mass spectrometry of 63Ni at the Munich Tandem Laboratory for estimating fast neutron fluences from the Hiroshima atomic bomb.

    PubMed

    Rühm, W; Knie, K; Rugel, G; Marchetti, A A; Faestermann, T; Wallner, C; McAninch, J E; Straume, T; Korschinek, G

    2000-10-01

    After the release of the present dosimetry system DS86 in 1987, measurements have shown that DS86 may substantially underestimate thermal neutron fluences at large distances (>1,000 m) from the hypocenter in Hiroshima. This discrepancy casts doubts on the DS86 neutron source term and, consequently, the survivors' estimated neutron doses. However, the doses were caused mainly by fast neutrons. To determine retrospectively fast neutron fluences in Hiroshima, the reaction 63Cu(n, p)63Ni can be used, if adequate copper samples can be found. Measuring 63Ni (half life 100 y) in Hiroshima samples requires a very sensitive technique, such as accelerator mass spectrometry (AMS), because of the relatively small amounts of 63Ni expected (approximately 10(5)-10(6) atoms per gram of copper). Experiments performed at Lawrence Livermore National Laboratory have demonstrated in 1996 that AMS can be used to measure 63Ni in Hiroshima copper samples. Subsequently, a collaboration was established with the Technical University of Munich in view of its potential to perform more sensitive measurements of 63Ni than the Livermore facility and in the interest of interlaboratory validation. This paper presents the progress made at the Munich facility in the measurement of 63Ni by AMS. The Munich accelerator mass spectrometry facility is a combination of a high energy tandem accelerator and a detection system featuring a gas-filled magnet. It is designed for high sensitivity measurements of long-lived radioisotopes. Optimization of the ion source setup has further improved the sensitivity for 63Ni by reducing the background level of the 63Cu isobar interference by about two orders of magnitude. Current background levels correspond to a ratio of 63Ni/Ni<2x10(-14) and suggest that, with adequate copper samples, the assessment of fast neutron fluences in Hiroshima and Nagasaki is possible for ground distances of up to 1500 m, and--under favorable conditions--even beyond. To demonstrate this

  8. Investigations of the output energy deviation and other parameters during commissioning of the four-rod radio frequency quadrupole at the Fermi National Accelerator Laboratory

    SciTech Connect

    Schmidt, J. S.; et al.,

    2014-03-01

    After 30 years of operation, the Cockcroft-Walton based injector at FNAL (Fermi National Accelerator Laboratory) has been replaced by a new beam line including a dimpled magnetron 35 keV source in combination with a 750 keV 4-rod Radio Frequency Quadrupole (RFQ). The new injector is followed by the existing drift tube linac (DTL). Prior to installation, a test beam line was built which included the magnetron source and the 4-rod RFQ with a number of beam measurement instrumentation. The first beam test with the RFQ showed an output energy deviation greater than 2.5%. Other problems also showed up which led to investigations of the output energy, power consumption and transmission properties using RF simulations which were complemented with additional beam measurements. The sources of this deviation and the mechanical modifications of the RFQ to solve this matter will be presented in this paper. Meanwhile, the nominal output energy of 750 keV has been confirmed and the new injector with the 4-rod RFQ is in full operation.

  9. Optimization and validation of an accelerated laboratory extraction method to estimate nitrogen release patterns of slow- and controlled-release fertilizers.

    PubMed

    Medina, L Carolina; Sartain, Jerry B; Obreza, Thomas A; Hall, William L; Thiex, Nancy J

    2014-01-01

    Several technologies have been proposed to characterize the nutrient release and availability patterns of enhanced-efficiency fertilizers (EEFs), especially slow-release fertilizers (SRFs) and controlled-release fertilizers (CRFs) during the last few decades. These technologies have been developed mainly by manufacturers and are product-specific based on the regulation and analysis of each EEF product. Despite previous efforts to characterize EEF materials, no validated method exists to assess their nutrient release patterns. However, the increased use of EEFs in specialty and nonspecialty markets requires an appropriate method to verify nutrient claims and material performance. A series of experiments were conducted to evaluate the effect of temperature, fertilizer test portion size, and extraction time on the performance of a 74 h accelerated laboratory extraction method to measure SRF and CRF nutrient release profiles. Temperature was the only factor that influenced nutrient release rate, with a highly marked effect for phosphorus and to a lesser extent for nitrogen (N) and potassium. Based on the results, the optimal extraction temperature set was: Extraction No. 1-2:00 h at 25 degrees C; Extraction No. 2-2:00 h at 50 degrees C; Extraction No. 3-20:00 h at 55 degrees C; and Extraction No. 4-50:00 h at 60 degrees C. Ruggedness of the method was tested by evaluating the effect of small changes in seven selected factors on method behavior using a fractional multifactorial design. Overall, the method showed ruggedness for measuring N release rates of coated CRFs.

  10. Clay particles - potential of positron annihilation lifetime spectroscopy (PALS) for studying interlayer spacing

    NASA Astrophysics Data System (ADS)

    Fong, N.; Guagliardo, P.; Williams, J.; Musumeci, A.; Martin, D.; Smith, S. V.

    2011-01-01

    Characterisation of clays is generally achieved by traditional methods, such as X-ray diffraction (XRD) and transmission electron microscopy (TEM). However, clays are often difficult to characterise due to lack of long-range order, thus these tools are not always reliable. Because interlayer spacing in clays can be adjusted to house molecules, there is growing interest to use these materials for drug delivery. Positron annihilation lifetime spectroscopy (PALS) was examined as an alternative tool to characterise a series of well-known clays. XRD of two layered double hydroxides; MgAl-LDH and MgGd-LDH, natural hectorite, fluoromica and laponite, and their PALS spectra were compared. XRD data was used to calculate the interlayer d- spacing in these materials and results show a decrease in interlayer spacing as the heavy metal ions are substituted for those of large ionic radii. Similar results were obtained for PALS data. This preliminary study suggests PALS has potential as a routine tool for characterising clay particles. Further work will examine the sensitivity and reliability of PALS to percent of metal doping and hydration in clay microstructure.

  11. A Convenient Ultraviolet Irradiation Technique for Synthesis of Antibacterial Ag-Pal Nanocomposite

    NASA Astrophysics Data System (ADS)

    Han, Shuai; Zhang, He; Kang, Lianwei; Li, Xiaoliang; Zhang, Chong; Dong, Yongjie; Qin, Shenjun

    2016-09-01

    In the present work, palygorskite (Pal) was initially subjected to an ion-exchange reaction with silver ions (Pal-Ag+). Subsequently, Ag-Pal nanocomposites were assembled by a convenient ultraviolet irradiation technique, using carbon dots (CDs) derived from wool fiber as the reducing agent. The obtained nanocomposites were characterized by powder X-ray diffraction (XRD), ultraviolet-visible (UV-vis) spectroscopy, transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy. The XRD patterns and UV-vis absorption spectra confirmed the formation of the Ag nanoparticles (NPs). Meanwhile, the TEM images showed that the Ag NPs, which exhibited sizes in the range of 3-7 nm, were located on the surface of the Pal nanofiber structures. Furthermore, the antibacterial activity of the nanocomposites was evaluated against Gram-positive ( Staphylococcus aureus) and Gram-negative ( Escherichia coli) bacteria by applying the disc diffusion method and minimum inhibitory concentration test. Owing to their good antibacterial properties, the Ag-Pal nanocomposites are considered to be a promising bactericide with great potential applications.

  12. A Convenient Ultraviolet Irradiation Technique for Synthesis of Antibacterial Ag-Pal Nanocomposite.

    PubMed

    Han, Shuai; Zhang, He; Kang, Lianwei; Li, Xiaoliang; Zhang, Chong; Dong, Yongjie; Qin, Shenjun

    2016-12-01

    In the present work, palygorskite (Pal) was initially subjected to an ion-exchange reaction with silver ions (Pal-Ag(+)). Subsequently, Ag-Pal nanocomposites were assembled by a convenient ultraviolet irradiation technique, using carbon dots (CDs) derived from wool fiber as the reducing agent. The obtained nanocomposites were characterized by powder X-ray diffraction (XRD), ultraviolet-visible (UV-vis) spectroscopy, transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy. The XRD patterns and UV-vis absorption spectra confirmed the formation of the Ag nanoparticles (NPs). Meanwhile, the TEM images showed that the Ag NPs, which exhibited sizes in the range of 3-7 nm, were located on the surface of the Pal nanofiber structures. Furthermore, the antibacterial activity of the nanocomposites was evaluated against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria by applying the disc diffusion method and minimum inhibitory concentration test. Owing to their good antibacterial properties, the Ag-Pal nanocomposites are considered to be a promising bactericide with great potential applications.

  13. PAL-XFEL cavity beam position monitor pick-up design and beam test

    NASA Astrophysics Data System (ADS)

    Lee, Sojeong; Park, Young Jung; Kim, Changbum; Kim, Seung Hwan; Shin, Dong Cheol; Han, Jang-Hui; Ko, In Soo

    2016-08-01

    As an X-ray Free Electron Laser, PAL-XFEL is about to start beam commissioning. X-band cavity beam position monitor (BPM) is used in the PAL-XFEL undulator beam line. Prototypes of cavity BPM pick-up were designed and fabricated to test the RF characteristics. Also, the beam test of a cavity BPM pick-up was done in the Injector Test Facility (ITF). In the beam test, the raw signal properties of the cavity BPM pick-up were measured at a 200 pC bunch charge. According to the RF test and beam test results, the prototype cavity BPM pick-up design was confirmed to meet the requirements of the PAL-XFEL cavity BPM system.

  14. Gluconic acid produced by Gluconacetobacter diazotrophicus Pal5 possesses antimicrobial properties.

    PubMed

    Nieto-Peñalver, Carlos G; Savino, María J; Bertini, Elisa V; Sánchez, Leandro A; de Figueroa, Lucía I C

    2014-09-01

    Gluconic acid is produced in large quantities by the endophytic and diazotrophic bacterium Gluconacetobacter diazotrophicus Pal5. This organic acid derives from direct oxidation of glucose by a pyrroloquinoline-quinone-linked glucose dehydrogenase in this plant growth-promoting bacterium. In the present article, evidence is presented showing that gluconic acid is also responsible for the antimicrobial activity of G. diazotrophicus Pal5. The broad antagonistic spectrum includes Gram-positive and -negative bacteria. Eukaryotic microorganisms are more resistant to growth inhibition by this acid. Inhibition by gluconic acid can be modified through the presence of other organic acids. In contrast to other microorganisms, the Quorum Sensing system of G. diazotrophicus Pal5, a regulatory mechanism that plays a key role in several microbe-microbe interactions, is not related to gluconic acid production and the concomitant antagonistic activity.

  15. Modification of source contribution in PALS by simulation using Geant4 code

    NASA Astrophysics Data System (ADS)

    Ning, Xia; Cao, Xingzhong; Li, Chong; Li, Demin; Zhang, Peng; Gong, Yihao; Xia, Rui; Wang, Baoyi; Wei, Long

    2017-04-01

    The contribution of positron source for the results of a positron annihilation lifetime spectrum (PALS) is simulated using Geant4 code. The geometrical structure of PALS measurement system is a sandwich structure: the 22Na radiation source is encapsulated by Kapton films, and the specimens are attached on the outside of the films. The probabilities of a positron being annihilated in the films, annihilated in the targets, and the effect of positrons reflected back from the specimen surface, are simulated. The probability of a positron annihilated in the film is related to the species of targets and the source film thickness. The simulation result is in reasonable agreement with the available experimental data. Thus, modification of the source contribution calculated by Geant4 is viable, and it beneficial for the analysis of the results of PALS.

  16. US Particle Accelerators at Age 50.

    ERIC Educational Resources Information Center

    Wilson, R. R.

    1981-01-01

    Reviews the development of accelerators over the past 50 years. Topics include: types of accelerators, including cyclotrons; sociology of accelerators (motivation, financing, construction, and use); impact of war; national laboratories; funding; applications; future projects; foreign projects; and international collaborations. (JN)

  17. Palăśa (Butea monosperma (Lamk.) Taub.) and its medico-historical study.

    PubMed

    Prasad, P V V; Subhaktha, P K J P; Narayana, Ala; Rao, M Mruthyumjaya

    2006-01-01

    Palăśa (Butea monosperma (Lamk.) Taub.) is considered sacred both by Hindus and Buddhists. It is known to the Hindus under the Sănskrt name Palăśa as it possesses valuable medicinal properties. This sacred tree is being called the treasurer of the gods and of sacrifice. It grows throughout India except in very arid parts and is a medium sized deciduous tree. Parts used are bark, leaf, flower, seed and gum. It is mainly useful as antihelmenthic appetizer, aphrodisiac, laxative etc. Thus its medico- historical aspects are being presented in this paper.

  18. DiPALS: Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis - a randomised controlled trial.

    PubMed Central

    McDermott, Christopher J; Bradburn, Mike J; Maguire, Chin; Cooper, Cindy L; Baird, Wendy O; Baxter, Susan K; Cohen, Judith; Cantrill, Hannah; Dixon, Simon; Ackroyd, Roger; Baudouin, Simon; Bentley, Andrew; Berrisford, Richard; Bianchi, Stephen; Bourke, Stephen C; Darlison, Roy; Ealing, John; Elliott, Mark; Fitzgerald, Patrick; Galloway, Simon; Hamdalla, Hisham; Hanemann, C Oliver; Hughes, Philip; Imam, Ibrahim; Karat, Dayalan; Leek, Roger; Maynard, Nick; Orrell, Richard W; Sarela, Abeezar; Stradling, John; Talbot, Kevin; Taylor, Lyn; Turner, Martin; Simonds, Anita K; Williams, Tim; Wedzicha, Wisia; Young, Carolyn; Shaw, Pamela J

    2016-01-01

    BACKGROUND Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease resulting in death, usually from respiratory failure, within 2-3 years of symptom onset. Non-invasive ventilation (NIV) is a treatment that when given to patients in respiratory failure leads to improved survival and quality of life. Diaphragm pacing (DP), using the NeuRx/4(®) diaphragm pacing system (DPS)™ (Synapse Biomedical, Oberlin, OH, USA), is a new technique that may offer additional or alternative benefits to patients with ALS who are in respiratory failure. OBJECTIVE The Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis (DiPALS) trial evaluated the effect of DP on survival over the study duration in patients with ALS with respiratory failure. DESIGN The DiPALS trial was a multicentre, parallel-group, open-label, randomised controlled trial incorporating health economic analyses and a qualitative longitudinal substudy. PARTICIPANTS Eligible participants had a diagnosis of ALS (ALS laboratory-supported probable, clinically probable or clinically definite according to the World Federation of Neurology revised El Escorial criteria), had been stabilised on riluzole for 30 days, were aged ≥ 18 years and were in respiratory failure. We planned to recruit 108 patients from seven UK-based specialist ALS or respiratory centres. Allocation was performed using 1 : 1 non-deterministic minimisation. INTERVENTIONS Participants were randomised to either standard care (NIV alone) or standard care (NIV) plus DP using the NeuRX/4 DPS. MAIN OUTCOME MEASURES The primary outcome was overall survival, defined as the time from randomisation to death from any cause. Secondary outcomes were patient quality of life [assessed by European Quality of Life-5 Dimensions, three levels (EQ-5D-3L), Short Form questionnaire-36 items and Sleep Apnoea Quality of Life Index questionnaire]; carer quality of life (EQ-5D-3L and Caregiver Burden Inventory); cost-utility analysis and health

  19. Validation of the Actigraph GT3X and ActivPAL Accelerometers for the Assessment of Sedentary Behavior

    ERIC Educational Resources Information Center

    Kim, Youngdeok; Barry, Vaughn W.; Kang, Minsoo

    2015-01-01

    This study examined (a) the validity of two accelerometers (ActiGraph GT3X [ActiGraph LLC, Pensacola, FL, USA] and activPAL [PAL Technologies Ltd., Glasgow, Scotland]) for the assessment of sedentary behavior; and (b) the variations in assessment accuracy by setting minimum sedentary bout durations against a proxy for direct observation using an…

  20. Problems with McAdams and Pals's (2006) Proposal of a Framework for an Integrative Theory of Personality

    ERIC Educational Resources Information Center

    Epstein, Seymour

    2007-01-01

    Comments on the original article "A New Big Five: Fundamental Principles for an Integrative Science of Personality," by Dan P. McAdams and Jennifer L. Pals (see record 2006-03947-002). Here, the current author begins with a critique of McAdams and Pals's (April 2006) five principles for a framework for an integrative theory of personality. The…

  1. Peptidoglycan-associated lipoprotein (Pal) of Gram-negative bacteria: function, structure, role in pathogenesis and potential application in immunoprophylaxis.

    PubMed

    Godlewska, Renata; Wiśniewska, Katarzyna; Pietras, Zbigniew; Jagusztyn-Krynicka, Elzbieta Katarzyna

    2009-09-01

    The protein Pal (peptidoglycan-associated lipoprotein) is anchored in the outer membrane (OM) of Gram-negative bacteria and interacts with Tol proteins. Tol-Pal proteins form two complexes: the first is composed of three inner membrane Tol proteins (TolA, TolQ and TolR); the second consists of the TolB and Pal proteins linked to the cell's OM. These complexes interact with one another forming a multiprotein membrane-spanning system. It has recently been demonstrated that Pal is essential for bacterial survival and pathogenesis, although its role in virulence has not been clearly defined. This review summarizes the available data concerning the structure and function of Pal and its role in pathogenesis.

  2. Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Sidorin, Anatoly

    2010-01-01

    In linear accelerators the particles are accelerated by either electrostatic fields or oscillating Radio Frequency (RF) fields. Accordingly the linear accelerators are divided in three large groups: electrostatic, induction and RF accelerators. Overview of the different types of accelerators is given. Stability of longitudinal and transverse motion in the RF linear accelerators is briefly discussed. The methods of beam focusing in linacs are described.

  3. VizieR Online Data Catalog: Pal1-I elemental equivalent widths and abundances (Monaco+, 2011)

    NASA Astrophysics Data System (ADS)

    Monaco, L.; Saviane, I.; Correnti, M.; Bonifacio, P.; Geisler, D.

    2010-11-01

    Table A1. reports the line list and atomic parameters adopted for the Palomar 1 giant Pal1-I and the Sun. For the Mn and Co lines we adopted the hyperfine structures (HFS) tabulated by Prochaska et al. (2000AJ....120.2513P). The measured equivalent width and the corresponding abundance obtained for each line are also reported. (1 data file).

  4. Pen Pal Letter Exchanges: Taking First Steps toward Developing Cultural Understandings

    ERIC Educational Resources Information Center

    Barksdale, Mary Alice; Watson, Carol; Park, Eun Soo

    2007-01-01

    This article describes a qualitative research project that examined pen pal letters exchanged between children in Virginia, USA, and Malawi in Sub-Saharan Africa. The goal was to study the nature of communication between students living in these two very different cultural contexts. The results of this study indicated that there were three primary…

  5. Peer Assessment Learning Sessions (PALS): An Innovative Feedback Technique for Large Engineering Classes

    ERIC Educational Resources Information Center

    O'Moore, Liza; Baldock, Tom

    2007-01-01

    This paper reports the development of innovative assessment sessions within two core technical courses in Civil Engineering at the University of Queensland. Peer Assessment Learning Sessions (PALS) facilitate a student's peer assessment of a colleague's problem-based learning assignment or tutorial within a "traditional" whole-class…

  6. Supplementation of CHROMagar Candida medium with Pal's medium for rapid identification of Candida dubliniensis.

    PubMed

    Sahand, Ismail H; Moragues, María D; Eraso, Elena; Villar-Vidal, María; Quindós, Guillermo; Pontón, José

    2005-11-01

    CHROMagar Candida medium is used for the isolation and identification of Candida species, but it does not differentiate Candida albicans from Candida dubliniensis. This differentiation can be achieved by using Pal's agar, which cannot be used in primary isolation. We have combined both media to obtain a new medium that can be used for the isolation and identification of C. dubliniensis in primary cultures.

  7. Connecting in Rhizomic Spaces: Peer-Assisted Learning (PAL) and E-Learning in Teacher Education

    ERIC Educational Resources Information Center

    Bone, Jane; Edwards, Susan

    2015-01-01

    A PAL (Peer-Assisted Learning) project supported research that focused on e-learning and Web 2.0 technologies as part of a pedagogical approach in the context of a tertiary institution. This project responded to a call for a rejuvenation of conventional approaches to pedagogy while teaching an early childhood unit in a large Australian university.…

  8. E-Pals: An Exercise in the Seduction of Student Technophobes.

    ERIC Educational Resources Information Center

    Cook, Susan L.

    This paper presents a case study of an "e-pal" experiment which suggests that negative assumptions and orientations toward computer technology for communication purposes can be altered through one-to-one peer relationships. The experiment was conducted through a communication seminar at a small private university in the Northwest.…

  9. Polar localization of Escherichia coli chemoreceptors requires an intact Tol-Pal complex.

    PubMed

    Santos, Thiago M A; Lin, Ti-Yu; Rajendran, Madhusudan; Anderson, Samantha M; Weibel, Douglas B

    2014-06-01

    Subcellular biomolecular localization is critical for the metabolic and structural properties of the cell. The functional implications of the spatiotemporal distribution of protein complexes during the bacterial cell cycle have long been acknowledged; however, the molecular mechanisms for generating and maintaining their dynamic localization in bacteria are not completely understood. Here we demonstrate that the trans-envelope Tol-Pal complex, a widely conserved component of the cell envelope of Gram-negative bacteria, is required to maintain the polar positioning of chemoreceptor clusters in Escherichia coli. Localization of the chemoreceptors was independent of phospholipid composition of the membrane and the curvature of the cell wall. Instead, our data indicate that chemoreceptors interact with components of the Tol-Pal complex and that this interaction is required to polarly localize chemoreceptor clusters. We found that disruption of the Tol-Pal complex perturbs the polar localization of chemoreceptors, alters cell motility, and affects chemotaxis. We propose that the E. coli Tol-Pal complex restricts mobility of the chemoreceptor clusters at the cell poles and may be involved in regulatory mechanisms that co-ordinate cell division and segregation of the chemosensory machinery.

  10. RaPAL Bulletin, Numbers 5-13, 1988-1990.

    ERIC Educational Resources Information Center

    RaPAL Bulletin, 1988

    1988-01-01

    This document consists of a 3-year compilation (9 issues) of the RaPAL (Research and Practice in Adult Literacy) Bulletin. Typical articles are: "Student Involvement in Research" (a report of a workshop by Alex Golightly, Nick Nicola, and Marilyn Stone); part of a dialogue between Paolo Freire and Ira Shor, writer/educators of Brazil and…

  11. Let's Be PALS: An Evidence-Based Approach to Professional Development

    ERIC Educational Resources Information Center

    Dunst, Carl J.; Trivette, Carol M.

    2009-01-01

    An evidence-based approach to professional development is described on the basis of the findings from a series of research syntheses and meta-analyses of adult learning methods and strategies. The approach, called PALS (Participatory Adult Learning Strategy), places major emphasis on both active learner involvement in all aspects of training…

  12. META-ANALYSIS OF PHYSICAL ACTIVITY LEVEL ( PAL ) DATA FOR U.S. YOUTH

    EPA Science Inventory

    This paper describes analytical research undertaken by EMRB staff to obtain age- and gender-specific distributions of Physical Activity Level (PAL) values for children measured in studies published between 1990-2004 in the clinical nutrition and exercise physiology literatures. ...

  13. StarPals International Young Astronomers' Network Collaborative Projects for IYA

    NASA Astrophysics Data System (ADS)

    Kingan, Jessi

    2008-09-01

    StarPals is a nascent non-profit organization with the goal of providing opportunities for international collaboration between students of all ages within space science research. We believe that by encouraging an interest in the cosmos, the one thing that is truly Universal, from a young age, students will not only further their knowledge of and interest in science but will learn valuable teamwork and life skills. The goal is to foster respect, understanding and appreciation of cultural diversity among all StarPals participants, whether students, teachers, or mentors. StarPals aims to inspire students by providing opportunities in which, more than simply visualizing themselves as research scientists, they can actually become one. The technologies of robotic telescopes, videoconferencing, and online classrooms are expanding the possibilities like never before. In honor of IYA2009, StarPals would like to encourage 400 schools to participate on a global scale in astronomy/cosmology research on various concurrent projects. We will offer in-person or online workshops and training sessions to teach the teachers. We will be seeking publication in scientific journals for some student research. For our current project, the Double Stars Challenge, students use the robotic telescopes to take a series of four images of one of 30 double stars from a list furnished by the US Naval Observatory and then use MPO Canopus software to take distance and position angle measurements. StarPals provides students with hands-on training, telescope time, and software to complete the imaging and measuring. A paper will be drafted from our research data and submitted to the Journal of Double Star Observations. The kids who participate in this project may potentially be the youngest contributors to an article in a vetted scientific journal. Kids rapidly adapt and improve their computer skills operating these telescopes and discover for themselves that science is COOL!

  14. High Gradient Accelerator Research

    SciTech Connect

    Temkin, Richard

    2016-07-12

    The goal of the MIT program of research on high gradient acceleration is the development of advanced acceleration concepts that lead to a practical and affordable next generation linear collider at the TeV energy level. Other applications, which are more near-term, include accelerators for materials processing; medicine; defense; mining; security; and inspection. The specific goals of the MIT program are: • Pioneering theoretical research on advanced structures for high gradient acceleration, including photonic structures and metamaterial structures; evaluation of the wakefields in these advanced structures • Experimental research to demonstrate the properties of advanced structures both in low-power microwave cold test and high-power, high-gradient test at megawatt power levels • Experimental research on microwave breakdown at high gradient including studies of breakdown phenomena induced by RF electric fields and RF magnetic fields; development of new diagnostics of the breakdown process • Theoretical research on the physics and engineering features of RF vacuum breakdown • Maintaining and improving the Haimson / MIT 17 GHz accelerator, the highest frequency operational accelerator in the world, a unique facility for accelerator research • Providing the Haimson / MIT 17 GHz accelerator facility as a facility for outside users • Active participation in the US DOE program of High Gradient Collaboration, including joint work with SLAC and with Los Alamos National Laboratory; participation of MIT students in research at the national laboratories • Training the next generation of Ph. D. students in the field of accelerator physics.

  15. PARTICLE ACCELERATOR

    DOEpatents

    Teng, L.C.

    1960-01-19

    ABS>A combination of two accelerators, a cyclotron and a ring-shaped accelerator which has a portion disposed tangentially to the cyclotron, is described. Means are provided to transfer particles from the cyclotron to the ring accelerator including a magnetic deflector within the cyclotron, a magnetic shield between the ring accelerator and the cyclotron, and a magnetic inflector within the ring accelerator.

  16. Acceleration in astrophysics

    SciTech Connect

    Colgate, S.A.

    1993-12-31

    The origin of cosmic rays and applicable laboratory experiments are discussed. Some of the problems of shock acceleration for the production of cosmic rays are discussed in the context of astrophysical conditions. These are: The presumed unique explanation of the power law spectrum is shown instead to be a universal property of all lossy accelerators; the extraordinary isotropy of cosmic rays and the limited diffusion distances implied by supernova induced shock acceleration requires a more frequent and space-filling source than supernovae; the near perfect adiabaticity of strong hydromagnetic turbulence necessary for reflecting the accelerated particles each doubling in energy roughly 10{sup 5} to {sup 6} scatterings with negligible energy loss seems most unlikely; the evidence for acceleration due to quasi-parallel heliosphere shocks is weak. There is small evidence for the expected strong hydromagnetic turbulence, and instead, only a small number of particles accelerate after only a few shock traversals; the acceleration of electrons in the same collisionless shock that accelerates ions is difficult to reconcile with the theoretical picture of strong hydromagnetic turbulence that reflects the ions. The hydromagnetic turbulence will appear adiabatic to the electrons at their much higher Larmor frequency and so the electrons should not be scattered incoherently as they must be for acceleration. Therefore the electrons must be accelerated by a different mechanism. This is unsatisfactory, because wherever electrons are accelerated these sites, observed in radio emission, may accelerate ions more favorably. The acceleration is coherent provided the reconnection is coherent, in which case the total flux, as for example of collimated radio sources, predicts single charge accelerated energies much greater than observed.

  17. PALS: A unique probe for the molecular organisation of biopolymer matrices

    NASA Astrophysics Data System (ADS)

    Roussenova, M.; Alam, M. A.

    2013-06-01

    This short review aims to illustrate the versatility of Positron Annihilation Lifetime Spectroscopy (PALS) when utilized for the characterization of biopolymers (e.g.: starch, fractionated maltooligomers, gelatin and cellulose derivatives) commonly used for the formulation of pharmaceutical encapsulants. By showing examples from a number of recent PALS studies, we illustrate that this technique can be used to probe the changes in thermodynamic state and molecular packing for a wide range of biopolymer matrices as a function of temperature, matrix composition and water content. This provides a basis for establishing composition-structure-property relationships for these materials, which would eventually enable the rational control of their macroscopic properties and the design of optimal encapsulating matrices and intelligent drug delivery systems.

  18. CNN-coupled Humanoid Panoramic Annular Lens (PAL)-Optical System for Military Applications (Feasibility Study)

    NASA Astrophysics Data System (ADS)

    Greguss, Pal

    2002-01-01

    This report results from a contract tasking OPTOPAL Panoramic Metrology Consulting as follows: This investigation will consist of adaptation of a Hungarian-developed single-piece imaging block, the Panoramic Annular Lens (PAL) and the CNN chip for a few military applications. A polar beam splitter will be placed immediately after the relay lens to obtain two image planes, one will be used by the existing 64X64 CNN-UM focal plane array processor chip. The other image plane will be projected on the space-variant CMOS retina-like digital camera GIOTTO. Using this configuration enables us to compensate for the relatively low pixel number of the CNN-UM array processor; further it will allow a real time switching from log-polar imaging to regular imaging and allow for the design of the humanoid PAL optical system.

  19. NCI QuitPal, an App from the National Cancer Institute | NIH MedlinePlus the Magazine

    MedlinePlus

    ... turn Javascript on. NCI QuitPal, an App from the National Cancer Institute Past Issues / Winter 2013 Table ... Institutes of Health National Cancer Institute What if the tools you need to quit smoking were as ...

  20. Structure and function of the Escherichia coli Tol-Pal stator protein TolR.

    PubMed

    Wojdyla, Justyna A; Cutts, Erin; Kaminska, Renata; Papadakos, Grigorios; Hopper, Jonathan T S; Stansfeld, Phillip J; Staunton, David; Robinson, Carol V; Kleanthous, Colin

    2015-10-30

    TolR is a 15-kDa inner membrane protein subunit of the Tol-Pal complex in Gram-negative bacteria, and its function is poorly understood. Tol-Pal is recruited to cell division sites where it is involved in maintaining the integrity of the outer membrane. TolR is related to MotB, the peptidoglycan (PG)-binding stator protein from the flagellum, suggesting it might serve a similar role in Tol-Pal. The only structure thus far reported for TolR is of the periplasmic domain from Haemophilus influenzae in which N- and C-terminal residues had been deleted (TolR(62-133), Escherichia coli numbering). H. influenzae TolR(62-133) is a symmetrical dimer with a large deep cleft at the dimer interface. Here, we present the 1.7-Å crystal structure of the intact periplasmic domain of E. coli TolR (TolR(36-142)). E. coli TolR(36-142) is also dimeric, but the architecture of the dimer is radically different from that of TolR(62-133) due to the intertwining of its N and C termini. TolR monomers are rotated ∼180° relative to each other as a result of this strand swapping, obliterating the putative PG-binding groove seen in TolR(62-133). We found that removal of the strand-swapped regions (TolR(60-133)) exposes cryptic PG binding activity that is absent in the full-length domain. We conclude that to function as a stator in the Tol-Pal complex dimeric TolR must undergo large scale structural remodeling reminiscent of that proposed for MotB, where the N- and C-terminal sequences unfold in order for the protein to both reach and bind the PG layer ∼90 Å away from the inner membrane.

  1. Supplementation of CHROMagar Candida Medium with Pal's Medium for Rapid Identification of Candida dubliniensis

    PubMed Central

    Sahand, Ismail H.; Moragues, María D.; Eraso, Elena; Villar-Vidal, María; Quindós, Guillermo; Pontón, José

    2005-01-01

    CHROMagar Candida medium is used for the isolation and identification of Candida species, but it does not differentiate Candida albicans from Candida dubliniensis. This differentiation can be achieved by using Pal's agar, which cannot be used in primary isolation. We have combined both media to obtain a new medium that can be used for the isolation and identification of C. dubliniensis in primary cultures. PMID:16272515

  2. Saccharothrix sp. PAL54, a new chloramphenicol-producing strain isolated from a Saharan soil.

    PubMed

    Aouiche, Adel; Sabaou, Nasserdine; Meklat, Atika; Zitouni, Abdelghani; Bijani, Christian; Mathieu, Florence; Lebrihi, Ahmed

    2012-03-01

    An actinomycete strain designated PAL54, producing an antibacterial substance, was isolated from a Saharan soil in Ghardaïa, Algeria. Morphological and chemical studies indicated that this strain belonged to the genus Saccharothrix. Analysis of the 16S rDNA sequence showed a similarity level ranging between 96.9 and 99.2% within Saccharothrix species, with S. longispora DSM 43749(T), the most closely related. DNA-DNA hybridization confirmed that strain PAL54 belonged to Saccharothrix longispora. It showed very strong activity against pathogenic Gram-positive and Gram-negative bacteria responsible for nosocomial infections and resistant to multiple antibiotics. Strain PAL54 secreted the antibiotic optimally during mid-stationary and decline phases of growth. One antibacterial compound was isolated from the culture broth and purified by HPLC. The active compound was elucidated by uv-visible and NMR spectroscopy and by mass spectrometry. The results showed that this compound was a D: (-)-threo chloramphenicol. This is the first report of chloramphenicol production by a Saccharothrix species.

  3. Gluconacetobacter diazotrophicus PAL5 possesses an active quorum sensing regulatory system.

    PubMed

    Bertini, Elisa V; Nieto Peñalver, Carlos G; Leguina, Ana C; Irazusta, Verónica P; de Figueroa, Lucía I C

    2014-09-01

    The endophytic bacterium Gluconacetobacter diazotrophicus colonizes a broad range of host plants. Its plant growth-promoting capability is related to the capacity to perform biological nitrogen fixation, the biosynthesis of siderophores, antimicrobial substances and the solubilization of mineral nutrients. Colonization of and survival in these endophytic niche requires a complex regulatory network. Among these, quorum sensing systems (QS) are signaling mechanisms involved in the control of several genes related to microbial interactions, host colonization and stress survival. G. diazotrophicus PAL5 possesses a QS composed of a luxR and a luxI homolog, and produces eight molecules from the AHL family as QS signals. In this report data are provided showing that glucose concentration modifies the relative levels of these signal molecules. The activity of G. diazotrophicus PAL5 QS is also altered in presence of other carbon sources and under saline stress conditions. Inactivation of the QS system of G. diazotrophicus PAL5 by means of a quorum quenching strategy allowed the identification of extracellular and intracellular proteins under the control of this regulatory mechanism.

  4. Isomaltulose synthase (PalI) of Klebsiella sp. LX3. Crystal structure and implication of mechanism.

    PubMed

    Zhang, Daohai; Li, Nan; Lok, Shee-Mei; Zhang, Lian-Hui; Swaminathan, Kunchithapadam

    2003-09-12

    Isomaltulose synthase from Klebsiella sp. LX3 (PalI, EC 5.4.99.11) catalyzes the isomerization of sucrose to produce isomaltulose (alpha-D-glucosylpyranosyl-1,6-D-fructofuranose) and trehalulose (alpha-D-glucosylpyranosyl-1,1-d-fructofuranose). The PalI structure, solved at 2.2-A resolution with an R-factor of 19.4% and Rfree of 24.2%, consists of three domains: an N-terminal catalytic (beta/alpha)8 domain, a subdomain between N beta 3 and N alpha 3, and a C-terminal domain having seven beta-strands. The active site architecture of PalI is identical to that of other glycoside hydrolase family 13 members, suggesting a similar mechanism in substrate binding and hydrolysis. However, a unique RLDRD motif in the proximity of the active site has been identified and shown biochemically to be responsible for sucrose isomerization. A two-step reaction mechanism for hydrolysis and isomerization, which occurs in the same pocket is proposed based on both the structural and biochemical data. Selected C-terminal truncations have been shown to reduce and even abolish the enzyme activity, consistent with the predicted role of the C-terminal residues in the maintenance of enzyme conformation and active site topology.

  5. One NASA: Sharing Knowledge Through an Agency-wide Process Asset Library (PAL)

    NASA Technical Reports Server (NTRS)

    Truss, Baraka J.

    2006-01-01

    This poster session will cover the key purpose and components behind implementing the NASA PAL website. This session will present the current results, describing the process used to create the website, the current usage measure, and will demonstrate how NASA is truly becoming ONE. The target audience for the poster session includes those currently implementing the CMMI model and looking for PAL adoption techniques. To continue to be the leader in space, science and technology, NASA is using this agency-wide PAL to share knowledge, work products and lessons learned through this website. Many organizations have failed to recognize how the efforts of process improvement fit into overall organizational effort. However, NASA as an agency has adopted the benefits of process improvement by the creation of this website to foster communication between its ten centers. The poster session will cover the following, topics outlined below: 1) Website purpose; 2) Characteristics of the website; 3) User accounts status; 4) Website content size; and 5) Usage percentages.

  6. Interannual covariability between actual evapotranspiration and PAL and GIMMS NDVIs of northern Asia

    USGS Publications Warehouse

    Suzuki, Rikie; Masuda, Kooiti; Dye, Dennis G.

    2007-01-01

    This study examined the covariability between interannual changes in the normalized difference vegetation index (NDVI) and actual evapotranspiration (ET). To reduce possible uncertainty in the NDVI time series, two NDVI datasets derived from Pathfinder AVHRR Land (PAL) data and the Global Inventory Monitoring and Modeling Studies (GIMMS) group were used. Analyses were conducted using data over northern Asia from 1982 to 2000. Interannual changes over 19 years in the PAL-NDVI and GIMMS-NDVI were compared with interannual changes in ET estimated from model-assimilated atmospheric data and gridded precipitation data. For both NDVI datasets, the annual maximum correlation with ET occurred in June, which is the beginning of the vegetation growing season. The PAL and GIMMS datasets showed a significant, positive correlation between interannual changes in the NDVI and ET over most of the vegetated land area in June. These results suggest that interannual changes in vegetation activity predominantly control interannual changes in ET in June. Based on analyses of interannual changes in temperature, precipitation, and the NDVI in June, the study area can be roughly divided into two regions, the warmth-dominated northernmost region and the wetness-dominated southern region, indicating that interannual changes in vegetation and the resultant interannual changes in ET are controlled by warmth and wetness in these two regions, respectively.

  7. Breakthrough: Fermilab Accelerator Technology

    ScienceCinema

    None

    2016-07-12

    There are more than 30,000 particle accelerators in operation around the world. At Fermilab, scientists are collaborating with other laboratories and industry to optimize the manufacturing processes for a new type of powerful accelerator that uses superconducting niobium cavities. Experimenting with unique polishing materials, a Fermilab team has now developed an efficient and environmentally friendly way of creating cavities that can propel particles with more than 30 million volts per meter.

  8. The apical complex protein Pals1 is required to maintain cerebellar progenitor cells in a proliferative state.

    PubMed

    Park, Jun Young; Hughes, Lucinda J; Moon, Uk Yeol; Park, Raehee; Kim, Sang-Bae; Tran, Khoi; Lee, Ju-Seog; Cho, Seo-Hee; Kim, Seonhee

    2016-01-01

    Through their biased localization and function within the cell, polarity complex proteins are necessary to establish the cellular asymmetry required for tissue organization. Well-characterized germinal zones, mitogenic signals and cell types make the cerebellum an excellent model for addressing the crucial function of polarity complex proteins in the generation and organization of neural tissues. Deletion of the apical polarity complex protein Pals1 in the developing cerebellum results in a remarkably undersized cerebellum with disrupted layers in poorly formed folia and strikingly reduced granule cell production. We demonstrate that Pals1 is not only essential for cerebellum organogenesis, but also for preventing premature differentiation and thus maintaining progenitor pools in cerebellar germinal zones, including cerebellar granule neuron precursors in the external granule layer. In the Pals1 mouse mutants, the expression of genes that regulate the cell cycle was diminished, correlating with the loss of the proliferating cell population of germinal zones. Furthermore, enhanced Shh signaling through activated Smo cannot overcome impaired cerebellar cell generation, arguing for an epistatic role of Pals1 in proliferation capacity. Our study identifies Pals1 as a novel intrinsic factor that regulates the generation of cerebellar cells and Pals1 deficiency as a potential inhibitor of overactive mitogenic signaling.

  9. The apical complex protein Pals1 is required to maintain cerebellar progenitor cells in a proliferative state

    PubMed Central

    Park, Jun Young; Hughes, Lucinda J.; Moon, Uk Yeol; Park, Raehee; Kim, Sang-Bae; Tran, Khoi; Lee, Ju-Seog; Cho, Seo-Hee; Kim, Seonhee

    2016-01-01

    Through their biased localization and function within the cell, polarity complex proteins are necessary to establish the cellular asymmetry required for tissue organization. Well-characterized germinal zones, mitogenic signals and cell types make the cerebellum an excellent model for addressing the crucial function of polarity complex proteins in the generation and organization of neural tissues. Deletion of the apical polarity complex protein Pals1 in the developing cerebellum results in a remarkably undersized cerebellum with disrupted layers in poorly formed folia and strikingly reduced granule cell production. We demonstrate that Pals1 is not only essential for cerebellum organogenesis, but also for preventing premature differentiation and thus maintaining progenitor pools in cerebellar germinal zones, including cerebellar granule neuron precursors in the external granule layer. In the Pals1 mouse mutants, the expression of genes that regulate the cell cycle was diminished, correlating with the loss of the proliferating cell population of germinal zones. Furthermore, enhanced Shh signaling through activated Smo cannot overcome impaired cerebellar cell generation, arguing for an epistatic role of Pals1 in proliferation capacity. Our study identifies Pals1 as a novel intrinsic factor that regulates the generation of cerebellar cells and Pals1 deficiency as a potential inhibitor of overactive mitogenic signaling. PMID:26657772

  10. Phenylalanine ammonia lyase from Arabidopsis thaliana (AtPAL2): a potent enzyme for the synthesis of non-canonical aromatic alpha-amino acids: Part I: Comparative characterization to the enzymes from Petroselinum crispum (PcPAL1) and Rhodosporidium toruloides (RtPAL).

    PubMed

    Dreßen, Alana; Hilberath, Thomas; Mackfeld, Ursula; Billmeier, Arne; Rudat, Jens; Pohl, Martina

    2017-04-06

    Phenylalanine ammonia lyase (PAL) from Arabidopsis thaliana (AtPAL2) was comparatively characterized to the well-studied enzyme from parsley (PcPAL1) and Rhodosporidium toruloides (RtPAL) with respect to kinetic parameters for the deamination and the amination reaction, pH- and temperature optima and the substrate range of the amination reaction. Whereas both plant enzymes are specific for phenylalanine, the bifunctional enzyme from Rhodosporidium toruloides shows KM-values for L-Phe and L-Tyr in the same order of magnitude and, compared to both plant enzymes, a 10-15-fold higher activity. At 30°C all enzymes were sufficiently stable with half-lives of 3.4days (PcPAL1), 4.6days (AtPAL2) and 9.7days (RtPAL/TAL). Very good results for the amination of various trans-cinnamic acid derivatives were obtained using E. coli cells as whole cell biocatalysts in ammonium carbonate buffer. Investigation of the substrate ranges gave interesting results for the newly tested enzymes from A. thaliana and R. toruloides. Only the latter accepts besides 4-hydroxy-CA also 3-methoxy-4-hydroxy-CA as a substrate, which is an interesting intermediate for the formation of pharmaceutically relevant L-Dopa. AtPAL2 is a very good catalyst for the formation of (S)-3-F-Phe, (S)-4-F-Phe and (S)-2-Cl-Phe. Such non-canonical amino acids are valuable building blocks for the formation of various drug molecules.

  11. Vacuum Beat Wave Accelerator

    NASA Astrophysics Data System (ADS)

    Moore, C. I.; Hafizi, B.; Ting, A.; Burris, H. R.; Sprangle, P.; Esarey, E.; Ganguly, A.; Hirshfield, J. L.

    1997-11-01

    The Vacuum Beat Wave Accelerator (VBWA) is a particle acceleration scheme which uses the non-linear ponderomotive beating of two different frequency laser beams to accelerate electrons. A proof-of-principle experiment to demonstrate the VBWA is underway at the Naval Research Laboratory (NRL). This experiment will use the beating of a 1054 nm and 527 nm laser pulse from the NRL T-cubed laser to generate the beat wave and a 4.5 MeV RF electron gun as the electron source. Simulation results and the experimental design will be presented. The suitability of using axicon or higher order Gaussian laser beams will also be discussed.

  12. Molecular cloning and promoter analysis of the specific salicylic acid biosynthetic pathway gene phenylalanine ammonia-lyase (AaPAL1) from Artemisia annua.

    PubMed

    Zhang, Ying; Fu, Xueqing; Hao, Xiaolong; Zhang, Lida; Wang, Luyao; Qian, Hongmei; Zhao, Jingya

    2016-07-01

    Phenylalanine ammonia-lyase (PAL) is the key enzyme in the biosynthetic pathway of salicylic acid (SA). In this study, a full-length cDNA of PAL gene (named as AaPAL1) was cloned from Artemisia annua. The gene contains an open reading frame of 2,151 bps encoding 716 amino acids. Comparative and bioinformatics analysis revealed that the polypeptide protein of AaPAL1 was highly homologous to PALs from other plant species. Southern blot analysis revealed that it belonged to a gene family with three members. Quantitative RT-PCR analysis of various tissues of A. annua showed that AaPAL1 transcript levels were highest in the young leaves. A 1160-bp promoter region was also isolated resulting in identification of distinct cis-regulatory elements including W-box, TGACG-motif, and TC-rich repeats. Quantitative RT-PCR indicated that AaPAL1 was upregulated by salinity, drought, wounding, and SA stresses, which were corroborated positively with the identified cis-elements within the promoter region. AaPAL1 was successfully expressed in Escherichia. coli and the enzyme activity of the purified AaPAL1 was approximately 287.2 U/mg. These results substantiated the involvement of AaPAL1 in the phenylalanine pathway.

  13. A Study of Variables That Affect Results in the ASTM D2274 Accelerated Stability Test. Part 1. Laboratory, Operator, and Process Variable Effects.

    DTIC Science & Technology

    1987-04-01

    indicator adsorption GC Gas chromatography HPLC High-pressure liquid chromatography Hz Hertz LCO Light-cycle oils L/hr Liters per hour urm Micrometers mg...Process- Var iah Ii’ F fee-t s P FLD CROUP I- SBGROUP h te IeO StI,1i Ii i t\\ P roe edtore DI) i f viCe *𔄃 AB RACT (Continue on reverSe *f necesSary and...34 APPENDIX A - QUESTIONNAIRE ON THE USE OF THE ASTM TEST FOR OXIDATION STABILITY OF DISTILLATE FUEL OIL (ACCELERATED

  14. Diagnostics for induction accelerators

    SciTech Connect

    Fessenden, T.J.

    1996-04-01

    The induction accelerator was conceived by N. C. Christofilos and first realized as the Astron accelerator that operated at LLNL from the early 1960`s to the end of 1975. This accelerator generated electron beams at energies near 6 MeV with typical currents of 600 Amperes in 400 ns pulses. The Advanced Test Accelerator (ATA) built at Livermore`s Site 300 produced 10,000 Ampere beams with pulse widths of 70 ns at energies approaching 50 MeV. Several other electron and ion induction accelerators have been fabricated at LLNL and LBNL. This paper reviews the principal diagnostics developed through efforts by scientists at both laboratories for measuring the current, position, energy, and emittance of beams generated by these high current, short pulse accelerators. Many of these diagnostics are closely related to those developed for other accelerators. However, the very fast and intense current pulses often require special diagnostic techniques and considerations. The physics and design of the more unique diagnostics developed for electron induction accelerators are presented and discussed in detail.

  15. Future accelerators (?)

    SciTech Connect

    John Womersley

    2003-08-21

    I describe the future accelerator facilities that are currently foreseen for electroweak scale physics, neutrino physics, and nuclear structure. I will explore the physics justification for these machines, and suggest how the case for future accelerators can be made.

  16. Biomedical accelerator mass spectrometry

    NASA Astrophysics Data System (ADS)

    Freeman, Stewart P. H. T.; Vogel, John S.

    1995-05-01

    Ultrasensitive SIMS with accelerator based spectrometers has recently begun to be applied to biomedical problems. Certain very long-lived radioisotopes of very low natural abundances can be used to trace metabolism at environmental dose levels ( [greater-or-equal, slanted] z mol in mg samples). 14C in particular can be employed to label a myriad of compounds. Competing technologies typically require super environmental doses that can perturb the system under investigation, followed by uncertain extrapolation to the low dose regime. 41Ca and 26Al are also used as elemental tracers. Given the sensitivity of the accelerator method, care must be taken to avoid contamination of the mass spectrometer and the apparatus employed in prior sample handling including chemical separation. This infant field comprises the efforts of a dozen accelerator laboratories. The Center for Accelerator Mass Spectrometry has been particularly active. In addition to collaborating with groups further afield, we are researching the kinematics and binding of genotoxins in-house, and we support innovative uses of our capability in the disciplines of chemistry, pharmacology, nutrition and physiology within the University of California. The field can be expected to grow further given the numerous potential applications and the efforts of several groups and companies to integrate more the accelerator technology into biomedical research programs; the development of miniaturized accelerator systems and ion sources capable of interfacing to conventional HPLC and GMC, etc. apparatus for complementary chemical analysis is anticipated for biomedical laboratories.

  17. Intercomparison of interannual changes in NDVI from PAL and GIMMS in relation to evapotranspiration over northern Asia

    NASA Astrophysics Data System (ADS)

    Suzuki, R.; Masuda, K.; Dye, D.

    2004-12-01

    Vegetation over an extensive area influences actual evapotranspiration (ET) from the land to the atmosphere mainly through transpiration activity. The authors' previous study (Suzuki and Masuda, 2004. J Meteor Soc Japan, 82, 1233 -- 1241) found an interannual covariability between ET and the Normalized Difference Vegetation Index (NDVI) over a continental-scale land surface. This result suggested that vegetation controls interannual variation in ET, and therefore vegetation change must be considered to predict future climate. In this prior study, NDVI data from the Pathfinder AVHRR Land (PAL) dataset were analyzed. However, studies of NDVI interannual change are subject to uncertainty, because NDVI data often contain errors associated with sensor- and atmosphere-related effects. This study is aimed toward reducing this uncertainty by employing another major NDVI dataset, from the Global Inventory Monitoring and Modeling Studies (GIMMS) group, in addition to PAL. GIMMS-NDVI data were produced with a calibration method that differs from the one employed for PAL-NDVI data. An intercomparison of the PAL-NDVI and GIMMS-NDVI datasets provide an effective basis for further analysis of the covariability of NDVI and ET interannual changes. The analysis was carried out for the northern Asia region from 1982 to 2000. 19-year interannual changes (monthly anomalies) in the PAL-NDVI and GIMMS-NDVI values were compared. The correlation coefficient (R) in summer months exhibits high positive values (over 0.8 in June). This result indicates that PAL-NDVI and GIMMS-NDVI display similar interannual variation for active growing season months. Interannual change in PAL-NDVI and GIMMS-NDVI were both compared with interannual change in model-assimilated ET. Although the R between GIMMS-NDVI and ET is slightly less than for PAL-NDVI and ET, for both NDVI datasets the annual maximum correlation with ET occurs in June, which is near the central period of the growing season. A positive

  18. Tethered gravity laboratories study

    NASA Technical Reports Server (NTRS)

    Lucchetti, F.

    1989-01-01

    The following subject areas are covered: (1) thermal control issues; (2) attitude control sybsystem; (3) configuration constraints; (4) payload; (5) acceleration requirements on Variable Gravity Laboratory (VGL); and (6) VGL configuration highlights.

  19. Tethered gravity laboratories study

    NASA Technical Reports Server (NTRS)

    Lucchetti, F.

    1989-01-01

    Variable Gravity Laboratory studies are discussed. The following subject areas are covered: (1) conceptual design and engineering analysis; (2) control strategies (fast crawling maneuvers, main perturbations and their effect upon the acceleration level); and (3) technology requirements.

  20. Free volume anomalies in mixed-cation glasses revealed by positron annihilation lifetime spectroscopy (PALS).

    PubMed

    Ingram, Malcolm D; Pas, Steven J; Cramer, Cornelia; Gao, Yong; Hill, Anita J

    2005-04-21

    PALS experiments reveal a minimum in ortho-positronium (o-Ps) lifetimes and a maximum in the corresponding intensities that emerge when mixed-cation (Li/Na) borate glasses are heated from ambient temperatures up to 473 K. These free volume 'anomalies' appear to be a true manifestation of the mixed alkali effect (MAE). They are consistent with a mechanism of ion transport involving cooperation between hops of unlike cations, resulting in increased disturbance of the glass network. The result lends support to the dynamic structure model.

  1. Structure and Function of the Escherichia coli Tol-Pal Stator Protein TolR*

    PubMed Central

    Wojdyla, Justyna A.; Cutts, Erin; Kaminska, Renata; Papadakos, Grigorios; Hopper, Jonathan T. S.; Stansfeld, Phillip J.; Staunton, David; Robinson, Carol V.; Kleanthous, Colin

    2015-01-01

    TolR is a 15-kDa inner membrane protein subunit of the Tol-Pal complex in Gram-negative bacteria, and its function is poorly understood. Tol-Pal is recruited to cell division sites where it is involved in maintaining the integrity of the outer membrane. TolR is related to MotB, the peptidoglycan (PG)-binding stator protein from the flagellum, suggesting it might serve a similar role in Tol-Pal. The only structure thus far reported for TolR is of the periplasmic domain from Haemophilus influenzae in which N- and C-terminal residues had been deleted (TolR(62–133), Escherichia coli numbering). H. influenzae TolR(62–133) is a symmetrical dimer with a large deep cleft at the dimer interface. Here, we present the 1.7-Å crystal structure of the intact periplasmic domain of E. coli TolR (TolR(36–142)). E. coli TolR(36–142) is also dimeric, but the architecture of the dimer is radically different from that of TolR(62–133) due to the intertwining of its N and C termini. TolR monomers are rotated ∼180° relative to each other as a result of this strand swapping, obliterating the putative PG-binding groove seen in TolR(62–133). We found that removal of the strand-swapped regions (TolR(60–133)) exposes cryptic PG binding activity that is absent in the full-length domain. We conclude that to function as a stator in the Tol-Pal complex dimeric TolR must undergo large scale structural remodeling reminiscent of that proposed for MotB, where the N- and C-terminal sequences unfold in order for the protein to both reach and bind the PG layer ∼90 Å away from the inner membrane. PMID:26354441

  2. Antimicrobial activity of saquayamycins produced by Streptomyces spp. PAL114 isolated from a Saharan soil.

    PubMed

    Aouiche, A; Bijani, C; Zitouni, A; Mathieu, F; Sabaou, N

    2014-06-01

    A new strain of actinomycete designated PAL114, producing antimicrobial compounds, was isolated from a Saharan soil in Ghardaïa, Algeria. Morphological and chemical studies showed that this strain belonged to the genus Streptomyces. Two bioactive compounds, named P41A and P41B, were extracted by dichloromethane from the cell-free supernatant broth of strain PAL114 and were purified by HPLC. Minimum inhibitory concentrations of the pure antibiotics were determined against yeasts, filamentous fungi and bacteria, most of which are pathogenic or toxigenic for human and multiresistant to antibiotics. The strongest activities were observed against Candida albicans M3 and Bacillus subtilis ATCC 6633. The chemical structures of the compounds were determined by spectroscopic analysis of UV-visible and 1H and 13C NMR spectra and spectrometric analysis of mass spectrum. The compounds P41A and P41B were identified as saquayamycins A and C, respectively. These compounds belong to the aquayamycin-group antibiotics, which are known in the literature for their anticancer and antibacterial activities.

  3. Complete genome sequence of the sugarcane nitrogen-fixing endophyte Gluconacetobacter diazotrophicus Pal5

    PubMed Central

    Bertalan, Marcelo; Albano, Rodolpho; de Pádua, Vânia; Rouws, Luc; Rojas, Cristian; Hemerly, Adriana; Teixeira, Kátia; Schwab, Stefan; Araujo, Jean; Oliveira, André; França, Leonardo; Magalhães, Viviane; Alquéres, Sylvia; Cardoso, Alexander; Almeida, Wellington; Loureiro, Marcio Martins; Nogueira, Eduardo; Cidade, Daniela; Oliveira, Denise; Simão, Tatiana; Macedo, Jacyara; Valadão, Ana; Dreschsel, Marcela; Freitas, Flávia; Vidal, Marcia; Guedes, Helma; Rodrigues, Elisete; Meneses, Carlos; Brioso, Paulo; Pozzer, Luciana; Figueiredo, Daniel; Montano, Helena; Junior, Jadier; de Souza Filho, Gonçalo; Martin Quintana Flores, Victor; Ferreira, Beatriz; Branco, Alan; Gonzalez, Paula; Guillobel, Heloisa; Lemos, Melissa; Seibel, Luiz; Macedo, José; Alves-Ferreira, Marcio; Sachetto-Martins, Gilberto; Coelho, Ana; Santos, Eidy; Amaral, Gilda; Neves, Anna; Pacheco, Ana Beatriz; Carvalho, Daniela; Lery, Letícia; Bisch, Paulo; Rössle, Shaila C; Ürményi, Turán; Rael Pereira, Alessandra; Silva, Rosane; Rondinelli, Edson; von Krüger, Wanda; Martins, Orlando; Baldani, José Ivo; Ferreira, Paulo CG

    2009-01-01

    Background Gluconacetobacter diazotrophicus Pal5 is an endophytic diazotrophic bacterium that lives in association with sugarcane plants. It has important biotechnological features such as nitrogen fixation, plant growth promotion, sugar metabolism pathways, secretion of organic acids, synthesis of auxin and the occurrence of bacteriocins. Results Gluconacetobacter diazotrophicus Pal5 is the third diazotrophic endophytic bacterium to be completely sequenced. Its genome is composed of a 3.9 Mb chromosome and 2 plasmids of 16.6 and 38.8 kb, respectively. We annotated 3,938 coding sequences which reveal several characteristics related to the endophytic lifestyle such as nitrogen fixation, plant growth promotion, sugar metabolism, transport systems, synthesis of auxin and the occurrence of bacteriocins. Genomic analysis identified a core component of 894 genes shared with phylogenetically related bacteria. Gene clusters for gum-like polysaccharide biosynthesis, tad pilus, quorum sensing, for modulation of plant growth by indole acetic acid and mechanisms involved in tolerance to acidic conditions were identified and may be related to the sugarcane endophytic and plant-growth promoting traits of G. diazotrophicus. An accessory component of at least 851 genes distributed in genome islands was identified, and was most likely acquired by horizontal gene transfer. This portion of the genome has likely contributed to adaptation to the plant habitat. Conclusion The genome data offer an important resource of information that can be used to manipulate plant/bacterium interactions with the aim of improving sugarcane crop production and other biotechnological applications. PMID:19775431

  4. Phosphate enhances levan production in the endophytic bacterium Gluconacetobacter diazotrophicus Pal5

    PubMed Central

    Idogawa, Nao; Amamoto, Ryuta; Murata, Kousaku; Kawai, Shigeyuki

    2014-01-01

    Gluconacetobacter diazotrophicus is a gram-negative and endophytic nitrogen-fixing bacterium that has several beneficial effects in host plants; thus, utilization of this bacterium as a biofertilizer in agriculture may be possible. G. diazotrophicus synthesizes levan, a D-fructofuranosyl polymer with β-(2→6) linkages, as an exopolysaccharide and the synthesized levan improves the stress tolerance of the bacterium. In this study, we found that phosphate enhances levan production by G. diazotrophicus Pal5, a wild type strain that showed a stronger mucous phenotype on solid medium containing 28 mM phosphate than on solid medium containing 7 mM phosphate. A G. diazotrophicus Pal5 levansucrase disruptant showed only a weak mucous phenotype regardless of the phosphate concentration, indicating that the mucous phenotype observed on 28 mM phosphate medium was caused by levan. To our knowledge, this is the first report of the effect of a high concentration of phosphate on exopolysaccharide production. PMID:24717418

  5. Mutational analysis of the Aspergillus ambient pH receptor PalH underscores its potential as a target for antifungal compounds

    PubMed Central

    Lucena‐Agell, Daniel; Hervás‐Aguilar, América; Múnera‐Huertas, Tatiana; Pougovkina, Olga; Rudnicka, Joanna; Galindo, Antonio; Tilburn, Joan; Arst, Herbert N.

    2016-01-01

    Summary The pal/RIM ambient pH signalling pathway is crucial for the ability of pathogenic fungi to infect hosts. The Aspergillus nidulans 7‐TMD receptor PalH senses alkaline pH, subsequently facilitating ubiquitination of the arrestin PalF. Ubiquitinated PalF triggers downstream signalling events. The mechanism(s) by which PalH transduces the alkaline pH signal to PalF is poorly understood. We show that PalH is phosphorylated in a signal dependent manner, resembling mammalian GPCRs, although PalH phosphorylation, in contrast to mammalian GPCRs, is arrestin dependent. A genetic screen revealed that an ambient‐exposed region comprising the extracellular loop connecting TM4‐TM5 and ambient‐proximal residues within TM5 is required for signalling. In contrast, substitution by alanines of four aromatic residues within TM6 and TM7 results in a weak ‘constitutive’ activation of the pathway. Our data support the hypothesis that PalH mechanistically resembles mammalian GPCRs that signal via arrestins, such that the relative positions of individual helices within the heptahelical bundle determines the Pro316‐dependent transition between inactive and active PalH conformations, governed by an ambient‐exposed region including critical Tyr259 that potentially represents an agonist binding site. These findings open the possibility of screening for agonist compounds stabilizing the inactive conformation of PalH, which might act as antifungal drugs against ascomycetes. PMID:27279148

  6. Pharmacological inhibition of PAR2 with the pepducin P2pal-18S protects mice against acute experimental biliary pancreatitis

    PubMed Central

    Michael, E. S.; Kuliopulos, A.; Covic, L.; Steer, M. L.

    2013-01-01

    Pancreatic acinar cells express proteinase-activated receptor-2 (PAR2) that is activated by trypsin-like serine proteases and has been shown to exert model-specific effects on the severity of experimental pancreatitis, i.e., PAR2−/− mice are protected from experimental acute biliary pancreatitis but develop more severe secretagogue-induced pancreatitis. P2pal-18S is a novel pepducin lipopeptide that targets and inhibits PAR2. In studies monitoring PAR2-stimulated intracellular Ca2+ concentration changes, we show that P2pal-18S is a full PAR2 inhibitor in acinar cells. Our in vivo studies show that P2pal-18S significantly reduces the severity of experimental biliary pancreatitis induced by retrograde intraductal bile acid infusion, which mimics injury induced by endoscopic retrograde cholangiopancreatography (ERCP). This reduction in pancreatitis severity is observed when the pepducin is given before or 2 h after bile acid infusion but not when it is given 5 h after bile acid infusion. Conversely, P2pal-18S increases the severity of secretagogue-induced pancreatitis. In vitro studies indicate that P2pal-18S protects acinar cells against bile acid-induced injury/death, but it does not alter bile acid-induced intracellular zymogen activation. These studies are the first to report the effects of an effective PAR2 pharmacological inhibitor on pancreatic acinar cells and on the severity of experimental pancreatitis. They raise the possibility that a pepducin such as P2pal-18S might prove useful in the clinical management of patients at risk for developing severe biliary pancreatitis such as occurs following ERCP. PMID:23275617

  7. Pharmacological inhibition of PAR2 with the pepducin P2pal-18S protects mice against acute experimental biliary pancreatitis.

    PubMed

    Michael, E S; Kuliopulos, A; Covic, L; Steer, M L; Perides, G

    2013-03-01

    Pancreatic acinar cells express proteinase-activated receptor-2 (PAR2) that is activated by trypsin-like serine proteases and has been shown to exert model-specific effects on the severity of experimental pancreatitis, i.e., PAR2(-/-) mice are protected from experimental acute biliary pancreatitis but develop more severe secretagogue-induced pancreatitis. P2pal-18S is a novel pepducin lipopeptide that targets and inhibits PAR2. In studies monitoring PAR2-stimulated intracellular Ca(2+) concentration changes, we show that P2pal-18S is a full PAR2 inhibitor in acinar cells. Our in vivo studies show that P2pal-18S significantly reduces the severity of experimental biliary pancreatitis induced by retrograde intraductal bile acid infusion, which mimics injury induced by endoscopic retrograde cholangiopancreatography (ERCP). This reduction in pancreatitis severity is observed when the pepducin is given before or 2 h after bile acid infusion but not when it is given 5 h after bile acid infusion. Conversely, P2pal-18S increases the severity of secretagogue-induced pancreatitis. In vitro studies indicate that P2pal-18S protects acinar cells against bile acid-induced injury/death, but it does not alter bile acid-induced intracellular zymogen activation. These studies are the first to report the effects of an effective PAR2 pharmacological inhibitor on pancreatic acinar cells and on the severity of experimental pancreatitis. They raise the possibility that a pepducin such as P2pal-18S might prove useful in the clinical management of patients at risk for developing severe biliary pancreatitis such as occurs following ERCP.

  8. Vibration Analysis of the Space Shuttle External Tank Cable Tray Flight Data With and Without PAL Ramp

    NASA Technical Reports Server (NTRS)

    Walker, Bruce E.; Panda, Jayanta; Sutliff, Daniel L.

    2008-01-01

    External Tank Cable Tray vibration data for three successive Space Shuttle flights were analyzed to assess response to buffet and the effect of removal of the Protuberance Air Loads (PAL) ramp. Waveform integration, spectral analysis, cross-correlation analysis and wavelet analysis were employed to estimate vibration modes and temporal development of vibration motion from a sparse array of accelerometers and an on-board system that acquired 16 channels of data for approximately the first 2 min of each flight. The flight data indicated that PAL ramp removal had minimal effect on the fluctuating loads on the cable tray. The measured vibration frequencies and modes agreed well with predicted structural response.

  9. Vibration Analysis of the Space Shuttle External Tank Cable Tray Flight Data with and without PAL Ramp

    NASA Technical Reports Server (NTRS)

    Walker, B. E.; Panda, B. E.; Sutliff, D. L.

    2008-01-01

    External Tank Cable Tray vibration data for three successive Space Shuttle flights were analyzed to assess response to buffet and the effect of removal of the Protuberance Air Loads (PAL) ramp. Waveform integration, spectral analysis, cross-correlation analysis and wavelet analysis were employed to estimate vibration modes and temporal development of vibration motion from a sparse array of accelerometers and an on-board system that acquired 16 channels of data for approximately the first two minutes of each flight. The flight data indicated that PAL ramp removal had minimal effect on the fluctuating loads on the cable tray. The measured vibration frequencies and modes agreed well with predicted structural response.

  10. Accelerator and electrodynamics capability review

    SciTech Connect

    Jones, Kevin W

    2010-01-01

    Los Alamos National Laboratory (LANL) uses capability reviews to assess the science, technology and engineering (STE) quality and institutional integration and to advise Laboratory Management on the current and future health of the STE. Capability reviews address the STE integration that LANL uses to meet mission requirements. The Capability Review Committees serve a dual role of providing assessment of the Laboratory's technical contributions and integration towards its missions and providing advice to Laboratory Management. The assessments and advice are documented in reports prepared by the Capability Review Committees that are delivered to the Director and to the Principal Associate Director for Science, Technology and Engineering (PADSTE). Laboratory Management will use this report for STE assessment and planning. LANL has defined fifteen STE capabilities. Electrodynamics and Accelerators is one of the seven STE capabilities that LANL Management (Director, PADSTE, technical Associate Directors) has identified for review in Fiscal Year (FY) 2010. Accelerators and electrodynamics at LANL comprise a blend of large-scale facilities and innovative small-scale research with a growing focus on national security applications. This review is organized into five topical areas: (1) Free Electron Lasers; (2) Linear Accelerator Science and Technology; (3) Advanced Electromagnetics; (4) Next Generation Accelerator Concepts; and (5) National Security Accelerator Applications. The focus is on innovative technology with an emphasis on applications relevant to Laboratory mission. The role of Laboratory Directed Research and Development (LDRD) in support of accelerators/electrodynamics will be discussed. The review provides an opportunity for interaction with early career staff. Program sponsors and customers will provide their input on the value of the accelerator and electrodynamics capability to the Laboratory mission.

  11. HIGH GRADIENT INDUCTION ACCELERATOR

    SciTech Connect

    Caporaso, G J; Sampayan, S; Chen, Y; Blackfield, D; Harris, J; Hawkins, S; Holmes, C; Krogh, M; Nelson, S; Nunnally, W; Paul, A; Poole, B; Rhodes, M; Sanders, D; Selenes, K; Sullivan, J; Wang, L; Watson, J

    2007-06-21

    A new type of compact induction accelerator is under development at the Lawrence Livermore National Laboratory that promises to increase the average accelerating gradient by at least an order of magnitude over that of existing induction machines. The machine is based on the use of high gradient vacuum insulators, advanced dielectric materials and switches and is stimulated by the desire for compact flash x-ray radiography sources. Research describing an extreme variant of this technology aimed at proton therapy for cancer will be described. Progress in applying this technology to several applications will be reviewed.

  12. Molecular Characterization of a Recombinant Zea mays Phenylalanine Ammonia-Lyase (ZmPAL2) and Its Application in trans-Cinnamic Acid Production from L-Phenylalanine.

    PubMed

    Zang, Ying; Jiang, Ting; Cong, Ying; Zheng, Zhaojuan; Ouyang, Jia

    2015-06-01

    Phenylalanine ammonia-lyase (PAL) is one of the most extensively studied enzymes with its crucial role in secondary phenylpropanoid metabolism of plants. Recently, its demand has been increased for aromatic chemical production, but its applications in trans-cinnamic acid production were not much explored. In the present study, a putative PAL gene from Zea mays designated as ZmPAL2 was expressed and characterized in Escherichia coli BL21 (DE3). The recombinant ZmPAL2 exhibited a high PAL activity (7.14 U/mg) and a weak tyrosine ammonia-lyase activity. The optimal temperature of ZmPAL2 was 55 °C, and the thermal stability results showed that about 50 % of enzyme activity remained after a treatment at 60 °C for 6 h. The recombinant ZmPAL2 is a good candidate for the production of trans-cinnamic acid. The vitro conversion indicated that the recombinant ZmPAL2 could effectively catalyze the L-phenylalanine to trans-cinnamic acid, and the trans-cinnamic acid concentration can reach up to 5 g/l.

  13. Structures of the human Pals1 PDZ domain with and without ligand suggest gated access of Crb to the PDZ peptide-binding groove

    SciTech Connect

    Ivanova, Marina E.; Fletcher, Georgina C.; O’Reilly, Nicola; Purkiss, Andrew G.; Thompson, Barry J.; McDonald, Neil Q.

    2015-03-01

    This study characterizes the interaction between the carboxy-terminal (ERLI) motif of the essential polarity protein Crb and the Pals1/Stardust PDZ-domain protein. Structures of human Pals1 PDZ with and without a Crb peptide are described, explaining the highly conserved nature of the ERLI motif and revealing a sterically blocked peptide-binding groove in the absence of ligand. Many components of epithelial polarity protein complexes possess PDZ domains that are required for protein interaction and recruitment to the apical plasma membrane. Apical localization of the Crumbs (Crb) transmembrane protein requires a PDZ-mediated interaction with Pals1 (protein-associated with Lin7, Stardust, MPP5), a member of the p55 family of membrane-associated guanylate kinases (MAGUKs). This study describes the molecular interaction between the Crb carboxy-terminal motif (ERLI), which is required for Drosophila cell polarity, and the Pals1 PDZ domain using crystallography and fluorescence polarization. Only the last four Crb residues contribute to Pals1 PDZ-domain binding affinity, with specificity contributed by conserved charged interactions. Comparison of the Crb-bound Pals1 PDZ structure with an apo Pals1 structure reveals a key Phe side chain that gates access to the PDZ peptide-binding groove. Removal of this side chain enhances the binding affinity by more than fivefold, suggesting that access of Crb to Pals1 may be regulated by intradomain contacts or by protein–protein interaction.

  14. New methods for high current fast ion beam production by laser-driven acceleration.

    PubMed

    Margarone, D; Krasa, J; Prokupek, J; Velyhan, A; Torrisi, L; Picciotto, A; Giuffrida, L; Gammino, S; Cirrone, P; Cutroneo, M; Romano, F; Serra, E; Mangione, A; Rosinski, M; Parys, P; Ryc, L; Limpouch, J; Laska, L; Jungwirth, K; Ullschmied, J; Mocek, T; Korn, G; Rus, B

    2012-02-01

    An overview of the last experimental campaigns on laser-driven ion acceleration performed at the PALS facility in Prague is given. Both the 2 TW, sub-nanosecond iodine laser system and the 20 TW, femtosecond Ti:sapphire laser, recently installed at PALS, are used along our experiments performed in the intensity range 10(16)-10(19) W∕cm(2). The main goal of our studies was to generate high energy, high current ion streams at relatively low laser intensities. The discussed experimental investigations show promising results in terms of maximum ion energy and current density, which make the laser-accelerated ion beams a candidate for new-generation ion sources to be employed in medicine, nuclear physics, matter physics, and industry.

  15. From the Last Interglacial to the Anthropocene: Modelling a Complete Glacial Cycle (PalMod)

    NASA Astrophysics Data System (ADS)

    Brücher, Tim; Latif, Mojib; Claussen, Martin; Schulz, Michael

    2016-04-01

    We will give a short overview of the national climate modelling initiative (PalMod - Paleo Modelling, www.palmod.de) on the understanding of the climate system dynamics and its variability during the last glacial cycle. PalMod is funded by the German Federal Ministry of Education and Research (BMBF) and its specific topics are: (i) to identify and quantify the relative contributions of the fundamental processes which determined the Earth's climate trajectory and variability during the last glacial cycle, (ii) to simulate with comprehensive Earth System Models (ESMs) the climate from the peak of the last interglacial - the Eemian warm period - up to the present, including the changes in the spectrum of variability, and (iii) to assess possible future climate trajectories beyond this century during the next millennia with sophisticated ESMs tested in such a way. The research is intended to be conducted over a period of 10 years, but with shorter funding cycles. The envisioned approach is innovative in three respects. First, the consortium aims at simulating a full glacial cycle in transient mode and with comprehensive ESMs which allow full interactions between the physical and biogeochemical components of the Earth system, including ice sheets. Second, we shall address climate variability during the last glacial cycle on a large range of time scales, from interannual to multi-millennial, and attempt to quantify the relative contributions of external forcing and processes internal to the Earth system to climate variability at different time scales. Third, in order to achieve a higher level of understanding of natural climate variability at time scales of millennia, its governing processes and implications for the future climate, we bring together three different research communities: the Earth system modeling community, the proxy data community and the computational science community. The consortium consists of 18 partners including all major modelling centers within

  16. Rail accelerator research at Lewis Research Center

    NASA Technical Reports Server (NTRS)

    Kerslake, W. R.; Cybyk, B. Z.

    1982-01-01

    A rail accelerator was chosen for study as an electromagnetic space propulsion device because of its simplicity and existing technology base. The results of a mission feasibility study using a large rail accelerator for direct launch of ton-size payloads from the Earth's surface to space, and the results of initial tests with a small, laboratory rail accelerator are presented. The laboratory rail accelerator has a bore of 3 by 3 mm and has accelerated 60 mg projectiles to velocities of 300 to 1000 m/s. Rail materials of Cu, W, and Mo were tested for efficiency and erosion rate.

  17. Retrieving soil moisture for non-forested areas using PALS radiometer measurements in SMAPVEX12 field campaign

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper we investigate retrieval of soil moisture based on L-band brightness temperature under diverse conditions and land cover types. We apply the PALS (Passive Active L-band System) radiometer data collected in the SMAPVEX12 (Soil Moisture Active Passive Validation Experiment 2012) field ex...

  18. Relationships between salicylic acid content, phenylalanine ammonia-lyase (PAL) activity, and resistance of barley to aphid infestation.

    PubMed

    Chaman, Mercedes E; Copaja, Sylvia V; Argandoña, Victor H

    2003-04-09

    It has been suggested that salicylic acid (SA) is a signal in acquired resistance to pathogens in several plants. Also, it has been suggested that infestation of plants causes an increase in the activity of phenylalanine ammonia-lyase (PAL), a key phenolic biosynthesis enzyme. The purpose of this work was to investigate whether the induction of SA and PAL activity is related to the susceptibility of barley to aphid infestation. The induction of free and conjugated SA in two barley cultivars that differ in susceptibility to aphids was analyzed. Analyses of several physiological parameters showed that cv. UNA-80 was more susceptible to the aphid Schizaphis graminum than cv. LM-109. Salicylic acid was not detected in noninfested plants. Levels of free and conjugated SA in cv. LM-109 and of conjugated SA in cv. UNA-80 increased with aphid infestation, whereas the levels of free SA in cv. UNA-80 remained high under all infestation degrees. Maximum values reached in both cultivars were not significantly different. With respect to PAL activity, cv. LM-109 showed a significantly higher specific activity than cv. UNA-80, the more susceptible cultivar. The relationship between the susceptibility of a plant to aphid and SA induction and PAL activity is discussed.

  19. The "PALS" Prevention Program and Its Long-Term Impact on Student Intentions to Use Alcohol, Tobacco, and Marijuana

    ERIC Educational Resources Information Center

    Workman, Judson W.; Moore, Dennis; Huber, Mary J.; Wilson, Josephine F.; Ford, Jo Ann; Kinzeler, Nicole; Mayer, Theresa

    2012-01-01

    A unique Alcohol, Tobacco, and Other Drug (ATOD) prevention program called "PALS" (Prevention through Alternative Learning Styles) was implemented with middle school students with the goal of enhancing student knowledge of the harmful effects of ATOD, promoting the use of refusal skills and reducing intentions to use ATOD in the future.…

  20. Interfacial reactions in SiC{sub p}/Al composite fabricated by pressureless infiltration

    SciTech Connect

    Lee, K.B.; Kwon, H.

    1997-04-15

    Metal matrix composites (MMCs) reinforced by ceramic phases have been fabricated by various techniques including powder metallurgy, casting, etc. Recently Lanxide corporation developed the DIMOX and PRIMEX processes for fabricating ceramic- and metal-matrix composites, respectively. The PRIMEX process is an innovative technique for fabricating MMCs by the spontaneous infiltration of molten AL alloy containing Mg into a ceramic filler or preform under nitrogen atmosphere in pressureless state without the aid of vacuum or externally applied pressure. Although there were many patents on MMC fabrication by the above pressureless infiltration technique, however, few works on the resulting microstructures and their effects on mechanical properties were reported. Thus, in this study, the effects on interfacial reactions occurring during the fabrication of SiC{sub p}AL composite by the pressureless infiltration technique on microstructures and hardness have been investigated.

  1. High Current, High Density Arc Plasma as a New Source for WiPAL

    NASA Astrophysics Data System (ADS)

    Waleffe, Roger; Endrizzi, Doug; Myers, Rachel; Wallace, John; Clark, Mike; Forest, Cary; WiPAL Team

    2016-10-01

    The Wisconsin Plasma Astrophysics Lab (WiPAL) has installed a new array of nineteen plasma sources (plasma guns) on its 3 m diameter, spherical vacuum vessel. Each gun is a cylindrical, molybdenum, washer-stabilized, arc plasma source. During discharge, the guns are maintained at 1.2 kA across 100 V for 10 ms by the gun power supply establishing a high density plasma. Each plasma source is fired independently allowing for adjustable plasma parameters, with densities varying between 1018 -1019 m-3 and electron temperatures of 5-15 eV. Measurements were characterized using a 16 tip Langmuir probe. The plasma source will be used as a background plasma for the magnetized coaxial plasma gun (MCPG), the Terrestrial Reconnection Experiment (TREX), and as the plasma source for a magnetic mirror experiment. Temperature, density, and confinement results will be presented. This work is supported by the DoE and the NSF.

  2. Regulation of CDPKs, including identification of PAL kinase, in biotically stressed cells of French bean.

    PubMed

    Allwood, Ellen G; Davies, Dewi R; Gerrish, Chris; Bolwell, G Paul

    2002-07-01

    Changes in protein kinase activity have been investigated during the early response of suspension cultured cells of French bean to fungal elicitor. One of the kinases activated has a known target, phenylalanine ammonia-lyase (PAL), which has an important role in plant defence responses, and was purified. Kinase acivity during purification was monitored for both the PAL-derived peptide and syntide-2, which it also phosphorylated. The kinase had an Mr of 55,000 on the basis of gel migration, 45Ca2+ binding, autophosphorylation and phosphorylation of various substrates using in-gel assays. The kinase has been characterised with respect to kinetics and other properties in vitro and appears to be a CDPK. In-gel assays were also used to show that this kinase and a number of other CDPKs of similar Mr showed complex changes in elicitor-treated suspension-cultured cells of French bean. An activation was observed within 10 min and was maintained for up to 4 h. The time course of activation was different from MAP kinase and casein kinase assayed in the same extracts. However, at 5 min after addition of elicitor there is a transient inactivation of the CDPKs before activation. This inactivation can be mimicked by adding forskolin to the cells 30 min before elicitation, which brings about changes in the cellular pH. Forskolin potentiates the oxidative burst when elicitor is subsequently added while the CDPK cannot be activated by elicitor upon forskolin treatment. In contrast, intracellular acidification brought about by forskolin brings about slight activation of MAPkinase.

  3. Accelerator simulation of astrophysical processes

    NASA Technical Reports Server (NTRS)

    Tombrello, T. A.

    1983-01-01

    Phenomena that involve accelerated ions in stellar processes that can be simulated with laboratory accelerators are described. Stellar evolutionary phases, such as the CNO cycle, have been partially explored with accelerators, up to the consumption of He by alpha particle radiative capture reactions. Further experimentation is indicated on reactions featuring N-13(p,gamma)O-14, O-15(alpha, gamma)Ne-19, and O-14(alpha,p)F-17. Accelerated beams interacting with thin foils produce reaction products that permit a determination of possible elemental abundances in stellar objects. Additionally, isotopic ratios observed in chondrites can be duplicated with accelerator beam interactions and thus constraints can be set on the conditions producing the meteorites. Data from isotopic fractionation from sputtering, i.e., blasting surface atoms from a material using a low energy ion beam, leads to possible models for processes occurring in supernova explosions. Finally, molecules can be synthesized with accelerators and compared with spectroscopic observations of stellar winds.

  4. LINEAR ACCELERATOR

    DOEpatents

    Colgate, S.A.

    1958-05-27

    An improvement is presented in linear accelerators for charged particles with respect to the stable focusing of the particle beam. The improvement consists of providing a radial electric field transverse to the accelerating electric fields and angularly introducing the beam of particles in the field. The results of the foregoing is to achieve a beam which spirals about the axis of the acceleration path. The combination of the electric fields and angular motion of the particles cooperate to provide a stable and focused particle beam.

  5. Validity and reliability of the activPAL3 for measuring posture and stepping in adults and young people.

    PubMed

    Sellers, Ceri; Dall, Philippa; Grant, Margaret; Stansfield, Ben

    2016-01-01

    Characterisation of free-living physical activity requires the use of validated and reliable monitors. This study reports an evaluation of the validity and reliability of the activPAL3 monitor for the detection of posture and stepping in both adults and young people. Twenty adults (median 27.6y; IQR22.6y) and 8 young people (12.0y; IQR4.1y) performed standardised activities and activities of daily living (ADL) incorporating sedentary, upright and stepping activity. Agreement, specificity and positive predictive value were calculated between activPAL3 outcomes and the gold-standard of video observation. Inter-device reliability was calculated between 4 monitors. Sedentary and upright times for standardised activities were within ±5% of video observation as was step count (excluding jogging) for both adults and young people. Jogging step detection accuracy reduced with increasing cadence >150stepsmin(-1). For ADLs, sensitivity to stepping was very low for adults (40.4%) but higher for young people (76.1%). Inter-device reliability was either good (ICC(1,1)>0.75) or excellent (ICC(1,1)>0.90) for all outcomes. An excellent level of detection of standardised postures was demonstrated by the activPAL3. Postures such as seat-perching, kneeling and crouching were misclassified when compared to video observation. The activPAL3 appeared to accurately detect 'purposeful' stepping during ADL, but detection of smaller stepping movements was poor. Small variations in outcomes between monitors indicated that differences in monitor placement or hardware may affect outcomes. In general, the detection of posture and purposeful stepping with the activPAL3 was excellent indicating that it is a suitable monitor for characterising free-living posture and purposeful stepping activity in healthy adults and young people.

  6. Acceleration switch

    DOEpatents

    Abbin, Jr., Joseph P.; Devaney, Howard F.; Hake, Lewis W.

    1982-08-17

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  7. Acceleration switch

    DOEpatents

    Abbin, J.P. Jr.; Devaney, H.F.; Hake, L.W.

    1979-08-29

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  8. ION ACCELERATOR

    DOEpatents

    Bell, J.S.

    1959-09-15

    An arrangement for the drift tubes in a linear accelerator is described whereby each drift tube acts to shield the particles from the influence of the accelerating field and focuses the particles passing through the tube. In one embodiment the drift tube is splii longitudinally into quadrants supported along the axis of the accelerator by webs from a yoke, the quadrants. webs, and yoke being of magnetic material. A magnetic focusing action is produced by energizing a winding on each web to set up a magnetic field between adjacent quadrants. In the other embodiment the quadrants are electrically insulated from each other and have opposite polarity voltages on adjacent quadrants to provide an electric focusing fleld for the particles, with the quadrants spaced sufficienily close enough to shield the particles within the tube from the accelerating electric field.

  9. LINEAR ACCELERATOR

    DOEpatents

    Christofilos, N.C.; Polk, I.J.

    1959-02-17

    Improvements in linear particle accelerators are described. A drift tube system for a linear ion accelerator reduces gap capacity between adjacent drift tube ends. This is accomplished by reducing the ratio of the diameter of the drift tube to the diameter of the resonant cavity. Concentration of magnetic field intensity at the longitudinal midpoint of the external sunface of each drift tube is reduced by increasing the external drift tube diameter at the longitudinal center region.

  10. Enhanced efficiency of plasma acceleration in the laser-induced cavity pressure acceleration scheme

    NASA Astrophysics Data System (ADS)

    Badziak, J.; Rosiński, M.; Jabłoński, S.; Pisarczyk, T.; Chodukowski, T.; Parys, P.; Rączka, P.; Krousky, E.; Ullschmied, J.; Liska, R.; Kucharik, M.

    2015-01-01

    Among various methods for the acceleration of dense plasmas the mechanism called laser-induced cavity pressure acceleration (LICPA) is capable of achieving the highest energetic efficiency. In the LICPA scheme, a projectile placed in a cavity is accelerated along a guiding channel by the laser-induced thermal plasma pressure or by the radiation pressure of an intense laser radiation trapped in the cavity. This arrangement leads to a significant enhancement of the hydrodynamic or electromagnetic forces driving the projectile, relative to standard laser acceleration schemes. The aim of this paper is to review recent experimental and numerical works on LICPA with the emphasis on the acceleration of heavy plasma macroparticles and dense ion beams. The main experimental part concerns the research carried out at the kilojoule sub-nanosecond PALS laser facility in Prague. Our measurements performed at this facility, supported by advanced two-dimensional hydrodynamic simulations, have demonstrated that the LICPA accelerator working in the long-pulse hydrodynamic regime can be a highly efficient tool for the acceleration of heavy plasma macroparticles to hyper-velocities and the generation of ultra-high-pressure (>100 Mbar) shocks through the collision of the macroparticle with a solid target. The energetic efficiency of the macroparticle acceleration and the shock generation has been found to be significantly higher than that for other laser-based methods used so far. Using particle-in-cell simulations it is shown that the LICPA scheme is highly efficient also in the short-pulse high-intensity regime and, in particular, may be used for production of intense ion beams of multi-MeV to GeV ion energies with the energetic efficiency of tens of per cent, much higher than for conventional laser acceleration schemes.

  11. Characterization of the TolB-Pal trans-envelope complex from Xylella fastidiosa reveals a dynamic and coordinated protein expression profile during the biofilm development process.

    PubMed

    Santos, Clelton A; Janissen, Richard; Toledo, Marcelo A S; Beloti, Lilian L; Azzoni, Adriano R; Cotta, Monica A; Souza, Anete P

    2015-10-01

    The intriguing roles of the bacterial Tol-Pal trans-envelope protein complex range from maintenance of cell envelope integrity to potential participation in the process of cell division. In this study, we report the characterization of the XfTolB and XfPal proteins of the Tol-Pal complex of Xylella fastidiosa. X. fastidiosa is a major plant pathogen that forms biofilms inside xylem vessels, triggering the development of diseases in important cultivable plants around the word. Based on functional complementation experiments in Escherichia coli tolB and pal mutant strains, we confirmed the role of xftolB and xfpal in outer membrane integrity. In addition, we observed a dynamic and coordinated protein expression profile during the X. fastidiosa biofilm development process. Using small-angle X-ray scattering (SAXS), the low-resolution structure of the isolated XfTolB-XfPal complex in solution was solved for the first time. Finally, the localization of the XfTolB and XfPal polar ends was visualized via immunofluorescence labeling in vivo during bacterial cell growth. Our results highlight the major role of the components of the cell envelope, particularly the TolB-Pal complex, during the different phases of bacterial biofilm development.

  12. The Ve-mediated resistance response of the tomato to Verticillium dahliae involves H2O2, peroxidase and lignins and drives PAL gene expression

    PubMed Central

    2010-01-01

    Background Verticillium dahliae is a fungal pathogen that infects a wide range of hosts. The only known genes for resistance to Verticillium in the Solanaceae are found in the tomato (Solanum lycopersicum) Ve locus, formed by two linked genes, Ve1 and Ve2. To characterize the resistance response mediated by the tomato Ve gene, we inoculated two nearly isogenic tomato lines, LA3030 (ve/ve) and LA3038 (Ve/Ve), with V. dahliae. Results We found induction of H2O2 production in roots of inoculated plants, followed by an increase in peroxidase activity only in roots of inoculated resistant plants. Phenylalanine-ammonia lyase (PAL) activity was also increased in resistant roots 2 hours after inoculation, while induction of PAL activity in susceptible roots was not seen until 48 hours after inoculation. Phenylpropanoid metabolism was also affected, with increases in ferulic acid, p-coumaric acid, vanillin and p-hydroxybenzaldehyde contents in resistant roots after inoculation. Six tomato PAL cDNA sequences (PAL1 - PAL6) were found in the SolGenes tomato EST database. RT-PCR analysis showed that these genes were expressed in all organs of the plant, albeit at different levels. Real-time RT-PCR indicated distinct patterns of expression of the different PAL genes in V. dahliae-inoculated roots. Phylogenetic analysis of 48 partial PAL cDNAs corresponding to 19 plant species grouped angiosperm PAL sequences into four clusters, suggesting functional differences among the six tomato genes, with PAL2 and PAL6 presumably involved in lignification, and the remaining PAL genes implicated in other biological processes. An increase in the synthesis of lignins was found 16 and 28 days after inoculation in both lines; this increase was greater and faster to develop in the resistant line. In both resistant and susceptible inoculated plants, an increase in the ratio of guaiacyl/syringyl units was detected 16 days after inoculation, resulting from the lowered amount of syringyl units in the

  13. SPEAR3 Accelerator Physics Update

    SciTech Connect

    Safranek, James A.; Corbett, W.Jeff; Gierman, S.; Hettel, R.O.; Huang, X.; Nosochkov, Yuri; Sebek, Jim; Terebilo, Andrei; /SLAC

    2007-11-02

    The SPEAR3 storage ring at Stanford Synchrotron Radiation Laboratory has been delivering photon beams for three years. We will give an overview of recent and ongoing accelerator physics activities, including 500 mA fills, work toward top-off injection, long-term orbit stability characterization and improvement, fast orbit feedback, new chicane optics, low alpha optics & short bunches, low emittance optics, and MATLAB software. The accelerator physics group has a strong program to characterize and improve SPEAR3 performance

  14. Acceleration using total internal reflection

    SciTech Connect

    Fernow, R.C.

    1991-06-07

    This report considers the use of a dielectric slab undergoing total internal reflection as an accelerating structure for charged particle beams. We examine the functional dependence of the electromagnetic fields above the surface of the dielectric for polarized incident waves. We present an experimental arrangement for testing the performance of the method, using apparatus under construction for the Grating Acceleration experiment at Brookhaven National Laboratory. 13 refs., 4 figs., 2 tabs.

  15. Acceleration Studies

    NASA Technical Reports Server (NTRS)

    Rogers, Melissa J. B.

    1993-01-01

    Work to support the NASA MSFC Acceleration Characterization and Analysis Project (ACAP) was performed. Four tasks (analysis development, analysis research, analysis documentation, and acceleration analysis) were addressed by parallel projects. Work concentrated on preparation for and implementation of near real-time SAMS data analysis during the USMP-1 mission. User support documents and case specific software documentation and tutorials were developed. Information and results were presented to microgravity users. ACAP computer facilities need to be fully implemented and networked, data resources must be cataloged and accessible, future microgravity missions must be coordinated, and continued Orbiter characterization is necessary.

  16. Imaging using accelerated heavy ions

    SciTech Connect

    Chu, W.T.

    1982-05-01

    Several methods for imaging using accelerated heavy ion beams are being investigated at Lawrence Berkeley Laboratory. Using the HILAC (Heavy-Ion Linear Accelerator) as an injector, the Bevalac can accelerate fully stripped atomic nuclei from carbon (Z = 6) to krypton (Z = 34), and partly stripped ions up to uranium (Z = 92). Radiographic studies to date have been conducted with helium (from 184-inch cyclotron), carbon, oxygen, and neon beams. Useful ranges in tissue of 40 cm or more are available. To investigate the potential of heavy-ion projection radiography and computed tomography (CT), several methods and instrumentation have been studied.

  17. Science Highlight: Researchers Demonstrate 'Accelerator on a Chip'

    SciTech Connect

    2013-01-01

    In an advance that could dramatically shrink particle accelerators for science and medicine, researchers at DOE's SLAC National Accelerator Laboratory used a laser to accelerate electrons at a rate 10 times higher than conventional technology in a nanostructured glass chip smaller than a grain of rice. This technique uses ultrafast lasers to drive the accelerator. (This achievement was reported in Nature, 27 Sept 2013)

  18. Expression, crystallization and preliminary X-ray analysis of isomaltulose synthase (PalI) from Klebsiella sp. LX3.

    PubMed

    Li, Nan; Zhang, Daohai; Zhang, Lian-Hui; Swaminathan, Kunchithapadam

    2003-01-01

    Isomaltulose synthase (PalI) catalyzes the hydrolysis of the alpha-1,2 bond between the glucose and fructose moieties of sucrose and the formation of alpha-1,6 and alpha-1,1 bonds between the two components to produce isomaltulose (alpha-D-glucosylpyranosyl-1,6-D-fructofranose) and trehalulose (alpha-D-glucosylpyranosyl-1,1-D-fructofranose), respectively. The PalI protein has been overexpressed, purified and crystallized at 295 K using the hanging-drop vapour-diffusion method. The crystals diffract to 2.2 A resolution using synchrotron radiation and belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 59.239, b = 94.153, c = 111.294 A.

  19. Water-Vapor Sorption Processes in Nanoporous MgO-Al2O3 Ceramics: the PAL Spectroscopy Study

    NASA Astrophysics Data System (ADS)

    Klym, Halyna; Ingram, Adam; Shpotyuk, Oleh; Hadzaman, Ivan; Solntsev, Viacheslav

    2016-03-01

    The water-vapor sorption processes in nanoporous MgO-Al2O3 ceramics are studied with positron annihilation lifetime (PAL) spectroscopy employing positron trapping and positronium (Ps)-decaying modes. It is demonstrated that the longest-lived components in the four-term reconstructed PAL spectra with characteristic lifetimes near 2 and 60-70 ns can be, respectively, attributed to ortho-positronium (o-Ps) traps in nanopores with 0.3- and 1.5-1.8-nm radii. The first o-Ps decaying process includes "pick-off" annihilation in the "bubbles" of liquid water, while the second is based on o-Ps interaction with physisorbed water molecules at the walls of the pores. In addition, the water vapor modifies structural defects located at the grain boundaries in a vicinity of pores, this process being accompanied by void fragmentation during water adsorption and agglomeration during water desorption after drying.

  20. Water-Vapor Sorption Processes in Nanoporous MgO-Al2O3 Ceramics: the PAL Spectroscopy Study.

    PubMed

    Klym, Halyna; Ingram, Adam; Shpotyuk, Oleh; Hadzaman, Ivan; Solntsev, Viacheslav

    2016-12-01

    The water-vapor sorption processes in nanoporous MgO-Al2O3 ceramics are studied with positron annihilation lifetime (PAL) spectroscopy employing positron trapping and positronium (Ps)-decaying modes. It is demonstrated that the longest-lived components in the four-term reconstructed PAL spectra with characteristic lifetimes near 2 and 60-70 ns can be, respectively, attributed to ortho-positronium (o-Ps) traps in nanopores with 0.3- and 1.5-1.8-nm radii. The first o-Ps decaying process includes "pick-off" annihilation in the "bubbles" of liquid water, while the second is based on o-Ps interaction with physisorbed water molecules at the walls of the pores. In addition, the water vapor modifies structural defects located at the grain boundaries in a vicinity of pores, this process being accompanied by void fragmentation during water adsorption and agglomeration during water desorption after drying.

  1. Particle acceleration

    NASA Technical Reports Server (NTRS)

    Vlahos, L.; Machado, M. E.; Ramaty, R.; Murphy, R. J.; Alissandrakis, C.; Bai, T.; Batchelor, D.; Benz, A. O.; Chupp, E.; Ellison, D.

    1986-01-01

    Data is compiled from Solar Maximum Mission and Hinothori satellites, particle detectors in several satellites, ground based instruments, and balloon flights in order to answer fundamental questions relating to: (1) the requirements for the coronal magnetic field structure in the vicinity of the energization source; (2) the height (above the photosphere) of the energization source; (3) the time of energization; (4) transistion between coronal heating and flares; (5) evidence for purely thermal, purely nonthermal and hybrid type flares; (6) the time characteristics of the energization source; (7) whether every flare accelerates protons; (8) the location of the interaction site of the ions and relativistic electrons; (9) the energy spectra for ions and relativistic electrons; (10) the relationship between particles at the Sun and interplanetary space; (11) evidence for more than one acceleration mechanism; (12) whether there is single mechanism that will accelerate particles to all energies and also heat the plasma; and (13) how fast the existing mechanisms accelerate electrons up to several MeV and ions to 1 GeV.

  2. Plasma accelerator

    DOEpatents

    Wang, Zhehui; Barnes, Cris W.

    2002-01-01

    There has been invented an apparatus for acceleration of a plasma having coaxially positioned, constant diameter, cylindrical electrodes which are modified to converge (for a positive polarity inner electrode and a negatively charged outer electrode) at the plasma output end of the annulus between the electrodes to achieve improved particle flux per unit of power.

  3. Accelerated Achievement

    ERIC Educational Resources Information Center

    Ford, William J.

    2010-01-01

    This article focuses on the accelerated associate degree program at Ivy Tech Community College (Indiana) in which low-income students will receive an associate degree in one year. The three-year pilot program is funded by a $2.3 million grant from the Lumina Foundation for Education in Indianapolis and a $270,000 grant from the Indiana Commission…

  4. ACCELERATION INTEGRATOR

    DOEpatents

    Pope, K.E.

    1958-01-01

    This patent relates to an improved acceleration integrator and more particularly to apparatus of this nature which is gyrostabilized. The device may be used to sense the attainment by an airborne vehicle of a predetermined velocitv or distance along a given vector path. In its broad aspects, the acceleration integrator utilizes a magnetized element rotatable driven by a synchronous motor and having a cylin drical flux gap and a restrained eddy- current drag cap deposed to move into the gap. The angular velocity imparted to the rotatable cap shaft is transmitted in a positive manner to the magnetized element through a servo feedback loop. The resultant angular velocity of tae cap is proportional to the acceleration of the housing in this manner and means may be used to measure the velocity and operate switches at a pre-set magnitude. To make the above-described dcvice sensitive to acceleration in only one direction the magnetized element forms the spinning inertia element of a free gyroscope, and the outer housing functions as a gimbal of a gyroscope.

  5. UCLA Neptune Facility for Advanced Accelerator Studies

    SciTech Connect

    Tochitsky, Sergei Ya.; Clayton, Christopher E.; Marsh, Kenneth A.; Joshi, Chandrashekhar; Rosenzweig, James B.; Pellegrini, Claudio

    2004-12-07

    The Neptune Laboratory at UCLA is being used for exploring concepts useful for advanced accelerators. This facility hosts a TW-class CO2 laser system and a high-brightness photoinjector producing a 14 MeV electron beam. The goal for the laboratory is to carry out experiments on high-gradient acceleration of externally injected electrons in both laser-driven relativistic plasma waves and EM laser field in vacuum. Experiments on plasma beat-wave acceleration using a prebunched electron beam, a high-energy gain 10-{mu}m inverse free electron laser accelerator, longitudinal electron beam shaping and laser based light-sources are planned.

  6. The AstroPAL Starter Pack: How to Create a Grad Mentoring Program That Fosters Equity and Inclusion in Your Department

    NASA Astrophysics Data System (ADS)

    Cabrera, Nicole

    2017-01-01

    The Astronomy Peer Advising Leaders program (AstroPAL) at Georgia State University is a grassroots effort initiated by one PhD student with no budget, yet has quickly become a successful program that especially impacts students of marginalized identities. AstroPAL provides guidance for incoming grad students and helps them adjust to the workload, stress, and other difficulties that can come with grad school. This talk will cover the AstroPAL goals and accomplishments, its logistical structure, and its longterm sustainability. We will discuss how the program has helped create a bridge between faculty and students as well as the positive effect it has had on our community. I will also provide tools that anyone can use to launch AstroPAL at their home institution.

  7. Reliability and validity of the Functional Assessment of Chronic Illness Therapy-Palliative care (FACIT-Pal) scale.

    PubMed

    Lyons, Kathleen Doyle; Bakitas, Marie; Hegel, Mark T; Hanscom, Brett; Hull, Jay; Ahles, Tim A

    2009-01-01

    The Functional Assessment of Chronic Illness Therapy (FACIT) system provides a general, multidimensional measure of health-related quality of life (FACT-G) that can be augmented with disease or symptom-specific subscales. The 19-item palliative care subscale of the FACIT system has undergone little psychometric evaluation to date. The aim of this paper is to report the internal consistency, factor structure, and construct validity of the instrument using the palliative care subscale (FACIT-Pal). Two hundred fifty-six persons with advanced cancer in a randomized trial testing a palliative care psychoeducational intervention completed the 46-item FACIT-Pal at baseline. Internal consistency was greater than 0.74 for all subscales and the total score. Seventeen of the 19 palliative care subscale items loaded onto the four-factor solution of the established core measure (FACT-G). As hypothesized, total scores were correlated with measures of symptom intensity (r=-0.73, P<0.001) and depression (r=-0.75, P<0.001). The FACIT-Pal was able to discriminate between participants who died within three months of completing the baseline and participants who lived for at least one year after completing the baseline assessment (t=-4.05, P<0.001). The functional well-being subscale discriminated between participants who had a Karnofsky performance score of 70 and below and participants with a Karnofsky performance score of 80 and above (t=3.40, P<0.001). The findings support the internal consistency reliability and validity of the FACIT-Pal as a measure of health-related quality of life for persons with advanced cancer.

  8. VizieR Online Data Catalog: CCD photometry of Pal 1 (Borissova+ 1995)

    NASA Astrophysics Data System (ADS)

    Borissova, J.; Spassova, N.

    1997-06-01

    A CCD photometry of the halo cluster Palomar 1 is presented in the Thuan-Gunn photometric system. The principal sequences of the color-magnitude diagrams are delineated in different spectral bands. The color- magnitude diagrams of the cluster show a well defined red horizontal branch, a subgiant branch and a main-sequence down to about two magnitudes below the main sequence turnoff. The giant branch is absent and the brightest stars are the horizontal branch stars. The age of the cluster determined by comparison with the isochrones of Bell & VandenBerg (1987ApJS...63..335B) is consistent with an age in the interval 12-14Gyr. A distance modulus of (m-M)g0=15.38+/-0.15 magnitude and E(g-r)=0.16 has been derived. An estimate of the cluster structural parameters such as core radius and concentration parameter gives rc=1.5pc and c=1.46. A mass estimate of 1.1x103M⊙ and a mass-to-light ratio of 1.79 have been obtained using King's (1966AJ.....71...64K) method. The morphology of color-magnitude diagrams allows Pal 1 to be interpreted as probably a globular cluster rather than an old open one. For a description of the uvgr photometric system, see e.g. (1 data file).

  9. Passive aquatic listener (PAL): An adoptive underwater acoustic recording system for the marine environment

    NASA Astrophysics Data System (ADS)

    Anagnostou, Marios N.; Nystuen, Jeffrey A.; Anagnostou, Emmanouil N.; Papadopoulos, Anastasios; Lykousis, Vassilios

    2011-01-01

    The ambient sound field in the ocean is a combination of natural and manmade sounds. Consequently, the interpretation of the ambient sound field can be used to quantify these processes. In the frequency range from 1 to 50 kHz, the general character of ocean ambient sound is a slowly changing background that is closely associated with local wind speed, interspersed with shorter time scale events such as rain storms, ships and animal calls. At lower frequencies the underwater ambient sound budget includes geologically generated sound activities including underwater volcanic eruptions, seismic and seepage faults that generate bubbles, etc. that can also potentially be classified and quantified. Acoustic data are collected on hydrophones. Hydrophones are simple, robust sensors that can be deployed on most ocean instrumentation systems including surface or sub-surface moorings, bottom mounted systems, drifters, ARGO floats or autonomous underwater platforms. A dedicated oceanic underwater recorder called a passive acoustic listener (PAL) has been developed. A principal issue is to accurately distinguish different sound sources so that they can be quantified as part of a sound budget, and then quantified if appropriate. Based on ongoing data collected from the Poseidon II network the retrieval potential of multi-parameters from underwater sound, including meteorological (i.e., precipitation and winds) and in general geophysical, anthropogenetic (i.e., ships, submarines, etc.) and biological (whales, etc.) sources is presented.

  10. [An operational remote sensing algorithm of land surface evapotranspiration based on NOAA PAL dataset].

    PubMed

    Hou, Ying-Yu; He, Yan-Bo; Wang, Jian-Lin; Tian, Guo-Liang

    2009-10-01

    Based on the time series 10-day composite NOAA Pathfinder AVHRR Land (PAL) dataset (8 km x 8 km), and by using land surface energy balance equation and "VI-Ts" (vegetation index-land surface temperature) method, a new algorithm of land surface evapotranspiration (ET) was constructed. This new algorithm did not need the support from meteorological observation data, and all of its parameters and variables were directly inversed or derived from remote sensing data. A widely accepted ET model of remote sensing, i. e., SEBS model, was chosen to validate the new algorithm. The validation test showed that both the ET and its seasonal variation trend estimated by SEBS model and our new algorithm accorded well, suggesting that the ET estimated from the new algorithm was reliable, being able to reflect the actual land surface ET. The new ET algorithm of remote sensing was practical and operational, which offered a new approach to study the spatiotemporal variation of ET in continental scale and global scale based on the long-term time series satellite remote sensing images.

  11. Identification of N-acyl homoserine lactones produced by Gluconacetobacter diazotrophicus PAL5 cultured in complex and synthetic media.

    PubMed

    Nieto-Peñalver, Carlos G; Bertini, Elisa V; de Figueroa, Lucía I C

    2012-07-01

    The endophytic diazotrophic Gluconacetobacter diazotrophicus PAL5 was originally isolated from sugarcane (Saccharum officinarum). The biological nitrogen fixation, phytohormones secretion, solubilization of mineral nutrients and phytopathogen antagonism allow its classification as a plant growth-promoting bacterium. The recent genomic sequence of PAL5 unveiled the presence of a quorum sensing (QS) system. QS are regulatory mechanisms that, through the production of signal molecules or autoinducers, permit a microbial population the regulation of the physiology in a coordinated manner. The most studied autoinducers in gram-negative bacteria are the N-acyl homoserine lactones (AHLs). The usage of biosensor strains evidenced the presence of AHL-like molecules in cultures of G. diazotrophicus PAL5 grown in complex and synthetic media. Analysis of AHLs performed by LC-APCI-MS permitted the identification of eight different signal molecules, including C6-, C8-, C10-, C12- and C14-HSL. Mass spectra confirmed that this diazotrophic strain also synthesizes autoinducers with carbonyl substitutions in the acyl chain. No differences in the profile of AHLs could be determined under both culture conditions. However, although the level of short-chain AHLs was not affected, a decrease of 30% in the production of long-chain AHLs could be measured in synthetic medium.

  12. Differential effects of salinity and osmotic stress on the plant growth-promoting bacterium Gluconacetobacter diazotrophicus PAL5.

    PubMed

    De Oliveira, Marcos Vinicius V; Intorne, Aline C; Vespoli, Luciano de S; Madureira, Hérika C; Leandro, Mariana R; Pereira, Telma N S; Olivares, Fábio L; Berbert-Molina, Marília A; De Souza Filho, Gonçalo A

    2016-04-01

    Plant growth-promoting bacteria (PGPB) represent a promising alternative to the massive use of industrial fertilizers in agriculture. Gluconacetobacter diazotrophicus is a PGPB that colonizes several plant species. Although this bacterium is able to grow at high sucrose concentrations, its response to environmental stresses is poorly understood. The present study evaluated G. diazotrophicus PAL5 response to stresses caused by sucrose, PEG 400, NaCl, KCl, Na2SO4 and K2SO4. Morphological, ultrastructural and cell growth analysis revealed that G. diazotrophicus PAL5 is more sensitive to salt than osmotic stress. Growth inhibition and strong morphological changes were caused by salinity, in consequence of Cl ion-specific toxic effect. Interestingly, low osmotic stress levels were beneficial for bacterial multiplication, which was able to tolerate high sucrose concentrations, Na2SO4 and K2SO4. Our data show that G. diazotrophicus PAL5 has differential response to osmotic and salinity stress, which may influence its use as inoculant in saline environments.

  13. Essential role of K(+) uptake permease (Kup) for resistance to sucrose-induced stress in Gluconacetobacter diazotrophicus PAl 5.

    PubMed

    de Oliveira, Marcos V V; Intorne, Aline C; Vespoli, Luciano de S; Andrade, Leandro F; Pereira, Leandro de M; Rangel, Patrícia L; de Souza Filho, Gonçalo A

    2017-04-01

    Microorganisms are constantly challenged by stressful conditions, such as sugar-rich environments. Such environments can cause an imbalance of biochemical activities and compromise cell multiplication. Gluconacetobacter diazotrophicus PAl 5 is among the most sugar-tolerant bacteria, capable of growing in the presence of up to 876 mM sucrose. However, the molecular mechanisms involved in its response to high sucrose remain unknown. The present work aimed to identify sucrose-induced stress resistance genes in G. diazotrophicus PAl 5. Screening of a Tn5 transposon insertion library identified a mutant that was severely compromised in its resistance to high sucrose concentrations. Molecular characterization revealed that the mutation affected the kupA gene, which encodes a K(+) uptake transporter (KupA). Functional complementation of the mutant with the wild type kupA gene recovered the sucrose-induced stress resistance phenotype. High sucrose resistance assay, under different potassium concentrations, revealed that KupA acts as a high-affinity K(+) transporter, which is essential for resistance to sucrose-induced stress, when extracellular potassium levels are low. This study is the first to show the essential role of the KupA protein for resistance to sucrose-induced stress in bacteria by acting as a high-affinity potassium transporter in G. diazotrophicus PAl 5.

  14. Optical design of a dual-channel two-focal-length system by utilizing azimuth property of PAL structure

    NASA Astrophysics Data System (ADS)

    Xu, Chen; Cheng, Dewen; Wang, Yongtian

    2016-10-01

    An approach to design a dual-channel two-focal-length lens based on the panoramic annular lens (PAL) structure is presented in this paper. The method of establishing the second channel to eliminate the blind area has been explored in some documents, and mostly it is achieved by utilizing the front surface of the PAL block. But in this paper, we modified the PAL block and divided it into two channels according to their different azimuth direction. These two channels have different focal lengths. Thus, by rotating the system around its axis, optical step-zoom effect can be obtained. Finally, a dual-channel system with a radial zoom ratio of 3× is designed, of which the wide-angle channel has a field-of-view (FOV) of 60° (radial) ×60° (azimuthal) and the long focal length channel has a FOV of 20° (radial)×20° (azimuthal). These two channels share the same stop surface, relay lens, and the image sensor. And a thin glass plate with diffractive structure is placed before the image plane to further correct aberration and obtain a common back focal length for the two channels. This system may have applications in many fields, such as surveillance, robot vision, and foveal imaging.

  15. Effects of PHENYLALANINE AMMONIA LYASE (PAL) knockdown on cell wall composition, biomass digestibility, and biotic and abiotic stress responses in Brachypodium

    PubMed Central

    Cass, Cynthia L.; Peraldi, Antoine; Dowd, Patrick F.; Mottiar, Yaseen; Santoro, Nicholas; Karlen, Steven D.; Bukhman, Yury V.; Foster, Cliff E.; Thrower, Nick; Bruno, Laura C.; Moskvin, Oleg V.; Johnson, Eric T.; Willhoit, Megan E.; Phutane, Megha; Ralph, John; Mansfield, Shawn D.; Nicholson, Paul; Sedbrook, John C.

    2015-01-01

    The phenylpropanoid pathway in plants synthesizes a variety of structural and defence compounds, and is an important target in efforts to reduce cell wall lignin for improved biomass conversion to biofuels. Little is known concerning the trade-offs in grasses when perturbing the function of the first gene family in the pathway, PHENYLALANINE AMMONIA LYASE (PAL). Therefore, PAL isoforms in the model grass Brachypodium distachyon were targeted, by RNA interference (RNAi), and large reductions (up to 85%) in stem tissue transcript abundance for two of the eight putative BdPAL genes were identified. The cell walls of stems of BdPAL-knockdown plants had reductions of 43% in lignin and 57% in cell wall-bound ferulate, and a nearly 2-fold increase in the amounts of polysaccharide-derived carbohydrates released by thermochemical and hydrolytic enzymic partial digestion. PAL-knockdown plants exhibited delayed development and reduced root growth, along with increased susceptibilities to the fungal pathogens Fusarium culmorum and Magnaporthe oryzae. Surprisingly, these plants generally had wild-type (WT) resistances to caterpillar herbivory, drought, and ultraviolet light. RNA sequencing analyses revealed that the expression of genes associated with stress responses including ethylene biosynthesis and signalling were significantly altered in PAL knocked-down plants under non-challenging conditions. These data reveal that, although an attenuation of the phenylpropanoid pathway increases carbohydrate availability for biofuel, it can adversely affect plant growth and disease resistance to fungal pathogens. The data identify notable differences between the stress responses of these monocot pal mutants versus Arabidopsis (a dicot) pal mutants and provide insights into the challenges that may arise when deploying phenylpropanoid pathway-altered bioenergy crops. PMID:26093023

  16. Effects of PHENYLALANINE AMMONIA LYASE (PAL) knockdown on cell wall composition, biomass digestibility, and biotic and abiotic stress responses in Brachypodium

    DOE PAGES

    Cass, Cynthia L.; Peraldi, Antoine; Dowd, Patrick F.; ...

    2015-06-19

    The phenylpropanoid pathway in plants synthesizes a variety of structural and defence compounds, and is an important target in efforts to reduce cell wall lignin for improved biomass conversion to biofuels. Little is known concerning the trade-offs in grasses when perturbing the function of the first gene family in the pathway, PHENYLALANINE AMMONIA LYASE (PAL). Therefore, PAL isoforms in the model grass Brachypodium distachyon were targeted, by RNA interference (RNAi), and large reductions (up to 85%) in stem tissue transcript abundance for two of the eight putative BdPAL genes were identified. The cell walls of stems of BdPAL-knockdown plants hadmore » reductions of 43% in lignin and 57% in cell wall-bound ferulate, and a nearly 2-fold increase in the amounts of polysaccharide-derived carbohydrates released by thermochemical and hydrolytic enzymic partial digestion. PAL-knockdown plants exhibited delayed development and reduced root growth, along with increased susceptibilities to the fungal pathogens Fusarium culmorum and Magnaporthe oryzae. Surprisingly, these plants generally had wild-type (WT) resistances to caterpillar herbivory, drought, and ultraviolet light. RNA sequencing analyses revealed that the expression of genes associated with stress responses including ethylene biosynthesis and signalling were significantly altered in PAL knocked-down plants under non-challenging conditions. These data reveal that, although an attenuation of the phenylpropanoid pathway increases carbohydrate availability for biofuel, it can adversely affect plant growth and disease resistance to fungal pathogens. Lastly, the data identify notable differences between the stress responses of these monocot pal mutants versus Arabidopsis (a dicot) pal mutants and provide insights into the challenges that may arise when deploying phenylpropanoid pathway-altered bioenergy crops.« less

  17. A touch-screen based paired-associates learning (PAL) task for the rat may provide a translatable pharmacological model of human cognitive impairment.

    PubMed

    Talpos, John C; Aerts, Nancy; Fellini, Laetitia; Steckler, Thomas

    2014-07-01

    The use of touch-screen equipped operant boxes is an increasingly popular approach for modeling human cognition in the rodent. However little data is currently available describing the effects of pharmacological manipulations on touch-screen based tasks. Owing to the relationship between performance on visual-spatial paired associates learning (PAL) with schizophrenia and Alzheimer's disease one task of specific interest is the touch-screen PAL task developed for rodents (J. Talpos et al., 2009). The goal of this study was to profile a range of the commonly used pharmacological models of schizophrenia and Alzheimer's disease to investigate the sensitivity of PAL to these models of disease. Male Lister hooded rats were trained on PAL until stable performance was obtained. The effects of PCP, ketamine, amphetamine, LSD, scopolamine, and biperiden (recently proposed as an alternative to scopolamine) were then tested on animals performing the PAL task. While all compounds influenced responding during PAL, only PCP and amphetamine impaired performance with minimal changes in secondary measures (response latencies, trials completed). Surprisingly ketamine did not cause a change in percent correct despite being an NMDA antagonist, indicating that not all NMDA antagonists are equal in the touch-screen platform. This finding is in agreement with existing literature showing differential effects of NMDA antagonists on a wide variety of behavioral assays include tasks of attention, memory, and cognitive flexibility (Gilmour et al., 2009; Dix et al., 2010; Smith et al., 2011). Moreover biperiden showed no benefit when compared to scopolamine, highlighting the current lack of an effective pharmacological model of cholinergic dysfunction in the touch-screen platform. These data demonstrate that performance on PAL can be disrupted by common pharmacological disease models, suggesting that PAL may have the sensitivity to serve as a translational test for the study of cognition in

  18. "Peer-assisted learning" (PAL) in the Skills-Lab--an inventory at the medical faculties of the Federal Republic of Germany.

    PubMed

    Blohm, M; Lauter, J; Branchereau, S; Krautter, M; Köhl-Hackert, N; Jünger, J; Herzog, W; Nikendei, C

    2015-01-01

    Hintergrund: Das didaktische Konzept des „Peer-assisted learning“ (PAL) hat sich seit vielen Jahren in der medizinischen Ausbildung als wertvoll erwiesen. Insbesondere im Bereich der inzwischen weit verbreiteten Skills-Labs ist der Einsatz studentischer Tutoren gleichermaßen beliebt wie effektiv. Ziel des vorliegenden Artikels ist, auf Basis einer bundesweiten Befragung den aktuellen Stand über Verbreitung, Umfang und inhaltliche wie strukturelle Ausgestaltung der PAL-Programme in den Skills-Labs der deutschen Medizinischen Fakultäten zu erfassen.Methoden: Sämtliche 36 bundesdeutsche Medizinische Fakultäten wurden kontaktiert und um Teilnahme an der 16 Leitfragen umfassenden Befragung zur Struktur von bestehenden PAL-Programmen im Skills-Lab-Bereich auf telefonischem oder schriftlichem Wege gebeten. Die erhaltenen Daten wurden quantitativ und qualitativ ausgewertet.Ergebnisse: 35 von 36 (97,2%) medizinischen Fakultäten nahmen an der Befragung teil. Ein PAL-Programm existiert an 33 (91,7%) Standorten. Die Ergebnisse zeigen, dass hinsichtlich Umfang und Inhalten jedoch große Unterschiede zwischen den Fakultäten bestehen. Schlussfolgerungen: PAL ist an bundesdeutschen medizinischen Skills-Labs nahezu flächendeckend umgesetzt. Weitere Untersuchungen zur Konzeption und Standardisierung von Schulungskonzepten scheinen zentral für die Weiterentwicklung von PAL im Skills-Lab.

  19. Acceleration Environment of the International Space Station

    NASA Technical Reports Server (NTRS)

    McPherson, Kevin; Kelly, Eric; Keller, Jennifer

    2009-01-01

    Measurement of the microgravity acceleration environment on the International Space Station has been accomplished by two accelerometer systems since 2001. The Microgravity Acceleration Measurement System records the quasi-steady microgravity environment, including the influences of aerodynamic drag, vehicle rotation, and venting effects. Measurement of the vibratory/transient regime, comprised of vehicle, crew, and equipment disturbances, has been accomplished by the Space Acceleration Measurement System-II. Until the arrival of the Columbus Orbital Facility and the Japanese Experiment Module, the location of these sensors, and therefore, the measurement of the microgravity acceleration environment, has been limited to within the United States Laboratory. Japanese Aerospace Exploration Agency has developed a vibratory acceleration measurement system called the Microgravity Measurement Apparatus which will be deployed within the Japanese Experiment Module to make distributed measurements of the Japanese Experiment Module's vibratory acceleration environment. Two Space Acceleration Measurement System sensors from the United States Laboratory will be re-deployed to support vibratory acceleration data measurement within the Columbus Orbital Facility. The additional measurement opportunities resulting from the arrival of these new laboratories allows Principal Investigators with facilities located in these International Space Station research laboratories to obtain microgravity acceleration data in support of their sensitive experiments. The Principal Investigator Microgravity Services project, at NASA Glenn Research Center, in Cleveland, Ohio, has supported acceleration measurement systems and the microgravity scientific community through the processing, characterization, distribution, and archival of the microgravity acceleration data obtained from the International Space Station acceleration measurement systems. This paper summarizes the PIMS capabilities available

  20. Particle Accelerators in China

    NASA Astrophysics Data System (ADS)

    Zhang, Chuang; Fang, Shouxian

    As the special machines that can accelerate charged particle beams to high energy by using electromagnetic fields, particle accelerators have been widely applied in scientific research and various areas of society. The development of particle accelerators in China started in the early 1950s. After a brief review of the history of accelerators, this article describes in the following sections: particle colliders, heavy-ion accelerators, high-intensity proton accelerators, accelerator-based light sources, pulsed power accelerators, small scale accelerators, accelerators for applications, accelerator technology development and advanced accelerator concepts. The prospects of particle accelerators in China are also presented.

  1. Compact accelerator

    DOEpatents

    Caporaso, George J.; Sampayan, Stephen E.; Kirbie, Hugh C.

    2007-02-06

    A compact linear accelerator having at least one strip-shaped Blumlein module which guides a propagating wavefront between first and second ends and controls the output pulse at the second end. Each Blumlein module has first, second, and third planar conductor strips, with a first dielectric strip between the first and second conductor strips, and a second dielectric strip between the second and third conductor strips. Additionally, the compact linear accelerator includes a high voltage power supply connected to charge the second conductor strip to a high potential, and a switch for switching the high potential in the second conductor strip to at least one of the first and third conductor strips so as to initiate a propagating reverse polarity wavefront(s) in the corresponding dielectric strip(s).

  2. Laser acceleration

    NASA Astrophysics Data System (ADS)

    Tajima, T.; Nakajima, K.; Mourou, G.

    2017-02-01

    The fundamental idea of Laser Wakefield Acceleration (LWFA) is reviewed. An ultrafast intense laser pulse drives coherent wakefield with a relativistic amplitude robustly supported by the plasma. While the large amplitude of wakefields involves collective resonant oscillations of the eigenmode of the entire plasma electrons, the wake phase velocity ˜ c and ultrafastness of the laser pulse introduce the wake stability and rigidity. A large number of worldwide experiments show a rapid progress of this concept realization toward both the high-energy accelerator prospect and broad applications. The strong interest in this has been spurring and stimulating novel laser technologies, including the Chirped Pulse Amplification, the Thin Film Compression, the Coherent Amplification Network, and the Relativistic Mirror Compression. These in turn have created a conglomerate of novel science and technology with LWFA to form a new genre of high field science with many parameters of merit in this field increasing exponentially lately. This science has triggered a number of worldwide research centers and initiatives. Associated physics of ion acceleration, X-ray generation, and astrophysical processes of ultrahigh energy cosmic rays are reviewed. Applications such as X-ray free electron laser, cancer therapy, and radioisotope production etc. are considered. A new avenue of LWFA using nanomaterials is also emerging.

  3. BICEP's acceleration

    SciTech Connect

    Contaldi, Carlo R.

    2014-10-01

    The recent Bicep2 [1] detection of, what is claimed to be primordial B-modes, opens up the possibility of constraining not only the energy scale of inflation but also the detailed acceleration history that occurred during inflation. In turn this can be used to determine the shape of the inflaton potential V(φ) for the first time — if a single, scalar inflaton is assumed to be driving the acceleration. We carry out a Monte Carlo exploration of inflationary trajectories given the current data. Using this method we obtain a posterior distribution of possible acceleration profiles ε(N) as a function of e-fold N and derived posterior distributions of the primordial power spectrum P(k) and potential V(φ). We find that the Bicep2 result, in combination with Planck measurements of total intensity Cosmic Microwave Background (CMB) anisotropies, induces a significant feature in the scalar primordial spectrum at scales k∼ 10{sup -3} Mpc {sup -1}. This is in agreement with a previous detection of a suppression in the scalar power [2].

  4. Advanced concepts for acceleration

    SciTech Connect

    Keefe, D.

    1986-07-01

    Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations. (LEW)

  5. Investigation of the estrogenic activities of pesticides from Pal-dang reservoir by in vitro assay.

    PubMed

    Oh, Young Jin; Jung, Yeon Jung; Kang, Joon-Wun; Yoo, Young Sook

    2007-12-15

    Endocrine disruptors, when absorbed into the body, interfere with the normal function by mimicking or blocking the hormone system. To investigate compounds mimicking estrogen in the drinking water source of the residence of Seoul, the Pal-dang reservoir was monitored over a period of 5 years, between 2000 and 2004. Nine kinds of pesticide (carbaryl, DBCP, diazinon, fenitrothion, fenobucarb, flutolanil, iprobenphos, isoprothiolane and parathion) were found to exist in the river water sample. These compounds were detected at low concentrations in the water samples. The total concentration and those of each of these pesticides were below the permissible limits of the National Institute of Environmental Research (NIER), Korea. The estrogenic potencies of the nine pesticides were examined using an E-screen assay with MCF-7 BUS estrogen receptor (ER)-positive human breast cancer cells, with ER-negative MDA MB 231 cell lines also used to compare the results. From this, flutolanil and isoprothiolane were confirmed to have estrogenic activities as shown by the increasing MCF-7 BUS cell growth on their addition. In addition, the estrogen receptor alpha (ERalpha) protein, estrogen receptor-regulated progesterone receptor (PR) and pS2 mRNA levels on the addition of flutolanil and isoprothiolane were measured with MCF-7 BUS cells. It was observed that the levels of ERalpha protein decreased and those of the PR and pS2 genes increased on the addition of either flutolanil or isoprothiolane at concentrations of 10(-4) M, in the same manner as with the addition of 17beta-estradiol, which was used as the positive control. From these results, it was confirmed that flutolanil and isoprothiolane exhibit estrogenic activities, suggesting they might act through estrogen receptors.

  6. Temporal and structural evolution of the Early Palæogene rocks of the Seychelles microcontinent.

    PubMed

    Shellnutt, J Gregory; Yeh, Meng-Wan; Suga, Kenshi; Lee, Tung-Yi; Lee, Hao-Yang; Lin, Te-Hsien

    2017-12-01

    The Early Palæogene Silhouette/North Island volcano-plutonic complex was emplaced during the rifting of the Seychelles microcontinent from western India. The complex is thought to have been emplaced during magnetochron C28n. However, the magnetic polarities of the rocks are almost entirely reversed and inconsistent with a normal polarity. In this study we present new in situ zircon U/Pb geochronology of the different intrusive facies of the Silhouette/North Island complex in order to address the timing of emplacement and the apparent magnetic polarity dichotomy. The rocks from Silhouette yielded weighted mean (206)Pb/(238)U ages from 62.4 ± 0.9 Ma to 63.1 ± 0.9 Ma whereas the rocks from North Island yielded slightly younger mean ages between 60.6 ± 0.7 Ma to 61.0 ± 0.8 Ma. The secular latitudinal variation from Silhouette to North Island is consistent with the anticlockwise rotation of the Seychelles microcontinent and the measured polarities. The rocks from Silhouette were emplaced across a polarity cycle (C26r-C27n-C27r) and the rocks from North Island were emplaced entirely within a magnetic reversal (C26r). Moreover, the rocks from North Island and those from the conjugate margin of India are contemporaneous and together mark the culmination of rift-related magmatism.

  7. A Measure of Person-Centered Practices in Assisted Living: The PC-PAL

    PubMed Central

    Zimmerman, Sheryl; Allen, Josh; Cohen, Lauren W.; Pinkowitz, Jackie; Reed, David; Coffey, Walter O.; Reed, Peter; Lepore, Michael; Sloane, Philip D.

    2014-01-01

    Objectives Develop self-administered questionnaires of person-centeredness for completion by residents and staff in assisted living (AL), in response to concerns that AL is not person-centered; also, demonstrated person-centeredness is necessary for Medicaid support as a home and community-based services provider. Design Community-based participatory research partnership between a research team, a consortium of 11 stakeholder organizations, and others. Methods included literature review, item generation and reduction, cognitive testing, field testing, exploratory factor analysis, and convergent and discriminant validity testing. Setting Cognitive testing conducted in two AL residences and field testing conducted in 19 diverse, stratified AL residences in six states. Participants Eight residents and staff participated in cognitive testing, and 228 residents and 123 staff participated in field testing. Measurements Feasibility and psychometric testing of draft questionnaires that included 75 items (resident version) and 102 items (staff version), with parallel items on both versions as appropriate. Results The final resident questionnaire included 49 items and four factors: well-being and belonging, individualized care and services, social connectedness, and atmosphere. The staff questionnaire included 62 items and five factors: workforce practices, social connectedness, individualized care and services, atmosphere, and caregiver-resident relationships. Staff scored person-centeredness higher than did residents, reflecting their different perspectives. Conclusion The Person-Centered Practices in Assisted Living (PC-PAL) questionnaires measure person-centeredness from the perspectives of residents and staff, meaning that they reflect the concepts and items considered to be important to these key stakeholders. Use of these instruments to describe, assess, quantify, assure, and ultimately improve person-centeredness in AL is feasible and appropriate for all AL settings

  8. Accelerators and the Accelerator Community

    SciTech Connect

    Malamud, Ernest; Sessler, Andrew

    2008-06-01

    In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

  9. Impact accelerations

    NASA Technical Reports Server (NTRS)

    Vongierke, H. E.; Brinkley, J. W.

    1975-01-01

    The degree to which impact acceleration is an important factor in space flight environments depends primarily upon the technology of capsule landing deceleration and the weight permissible for the associated hardware: parachutes or deceleration rockets, inflatable air bags, or other impact attenuation systems. The problem most specific to space medicine is the potential change of impact tolerance due to reduced bone mass and muscle strength caused by prolonged weightlessness and physical inactivity. Impact hazards, tolerance limits, and human impact tolerance related to space missions are described.

  10. Measurement of Coriolis Acceleration with a Smartphone

    ERIC Educational Resources Information Center

    Shaku, Asif; Kraft, Jakob

    2016-01-01

    Undergraduate physics laboratories seldom have experiments that measure the Coriolis acceleration. This has traditionally been the case owing to the inherent complexities of making such measurements. Articles on the experimental determination of the Coriolis acceleration are few and far between in the physics literature. However, because modern…

  11. 25 MV tandem accelerator at Oak Ridge

    SciTech Connect

    Jones, C.M.

    1980-01-01

    A new heavy-ion accelerator facility is under construction at the Oak Ridge National Laboratory. A brief description of the scope and status of this project is presented with emphasis on the first operational experience with the 25 MV tandem accelerator.

  12. Accelerator mass spectrometry.

    PubMed

    Hellborg, Ragnar; Skog, Göran

    2008-01-01

    In this overview the technique of accelerator mass spectrometry (AMS) and its use are described. AMS is a highly sensitive method of counting atoms. It is used to detect very low concentrations of natural isotopic abundances (typically in the range between 10(-12) and 10(-16)) of both radionuclides and stable nuclides. The main advantages of AMS compared to conventional radiometric methods are the use of smaller samples (mg and even sub-mg size) and shorter measuring times (less than 1 hr). The equipment used for AMS is almost exclusively based on the electrostatic tandem accelerator, although some of the newest systems are based on a slightly different principle. Dedicated accelerators as well as older "nuclear physics machines" can be found in the 80 or so AMS laboratories in existence today. The most widely used isotope studied with AMS is 14C. Besides radiocarbon dating this isotope is used in climate studies, biomedicine applications and many other fields. More than 100,000 14C samples are measured per year. Other isotopes studied include 10Be, 26Al, 36Cl, 41Ca, 59Ni, 129I, U, and Pu. Although these measurements are important, the number of samples of these other isotopes measured each year is estimated to be less than 10% of the number of 14C samples.

  13. VLHC accelerator physics

    SciTech Connect

    Michael Blaskiewicz et al.

    2001-11-01

    A six-month design study for a future high energy hadron collider was initiated by the Fermilab director in October 2000. The request was to study a staged approach where a large circumference tunnel is built that initially would house a low field ({approx}2 T) collider with center-of-mass energy greater than 30 TeV and a peak (initial) luminosity of 10{sup 34} cm{sup -2}s{sup -1}. The tunnel was to be scoped, however, to support a future upgrade to a center-of-mass energy greater than 150 TeV with a peak luminosity of 2 x 10{sup 34} cm{sup -2} sec{sup -1} using high field ({approx} 10 T) superconducting magnet technology. In a collaboration with Brookhaven National Laboratory and Lawrence Berkeley National Laboratory, a report of the Design Study was produced by Fermilab in June 2001. 1 The Design Study focused on a Stage 1, 20 x 20 TeV collider using a 2-in-1 transmission line magnet and leads to a Stage 2, 87.5 x 87.5 TeV collider using 10 T Nb{sub 3}Sn magnet technology. The article that follows is a compilation of accelerator physics designs and computational results which contributed to the Design Study. Many of the parameters found in this report evolved during the study, and thus slight differences between this text and the Design Study report can be found. The present text, however, presents the major accelerator physics issues of the Very Large Hadron Collider as examined by the Design Study collaboration and provides a basis for discussion and further studies of VLHC accelerator parameters and design philosophies.

  14. Electron Acceleration by Transient Ion Foreshock Phenomena

    NASA Astrophysics Data System (ADS)

    Wilson, L. B., III; Turner, D. L.

    2015-12-01

    Particle acceleration is a topic of considerable interest in space, laboratory, and astrophysical plasmas as it is a fundamental physical process to all areas of physics. Recent THEMIS [e.g., Turner et al., 2014] and Wind [e.g., Wilson et al., 2013] observations have found evidence for strong particle acceleration at macro- and meso-scale structures and/or pulsations called transient ion foreshock phenomena (TIFP). Ion acceleration has been extensively studied, but electron acceleration has received less attention. Electron acceleration can arise from fundamentally different processes than those affecting ions due to differences in their gyroradii. Electron acceleration is ubiquitous, occurring in the solar corona (e.g., solar flares), magnetic reconnection, at shocks, astrophysical plasmas, etc. We present new results analyzing the dependencies of electron acceleration on the properties of TIFP observed by the THEMIS spacecraft.

  15. (Val(8))GLP-1-Glu-PAL: a GLP-1 agonist that improves hippocampal neurogenesis, glucose homeostasis, and β-cell function in high-fat-fed mice.

    PubMed

    Lennox, Rachael; Porter, David W; Flatt, Peter R; Gault, Victor A

    2013-04-01

    This study examined the biological properties of a novel GLP-1 peptide, (Val(8))GLP-1-Glu-PAL, engineered with an Ala(8)→Val(8) substitution and additional incorporation of a C(16) fatty acid moiety at Lys(26) via a glutamic acid linker. GLP-1 underwent 75 % degradation by DPP-IV over 8 h, whereas (Val(8))GLP-1 and (Val(8))GLP-1-Glu-PAL remained intact. All GLP-1 peptides significantly stimulated insulin secretion at 5.6 mM (1.3- to 4.9-fold, p<0.01 to p<0.001) and 16.7 mM glucose (1.5- to 2.3-fold, p<0.001). At higher concentrations (Val(8))GLP-1-Glu-PAL was significantly more potent at stimulating insulin secretion (1.2- to 1.3-fold, p<0.05). In high-fat-fed mice, all GLP-1 peptides significantly lowered plasma glucose concentrations (41-66 % decrease, p<0.05 to p<0.001), with (Val(8))GLP-1-Glu-PAL eliciting protracted glucose-lowering actions (32-59 % decrease, p<0.05 to p<0.01) when administered 8 h prior to a glucose load. Twice-daily administration of (Val(8))GLP-1-Glu-PAL in high-fat-fed mice for 21 days had no effect on bodyweight or food intake, but significantly lowered non-fasting plasma glucose (43-46 % decrease, p<0.05). (Val(8))GLP-1-Glu-PAL markedly decreased glycemic excursion following intraperitoneal glucose (32-48 % decrease, p<0.05), enhanced insulin response to glucose (2- to 2.3-fold, p<0.05 to p<0.01), and improved insulin sensitivity (25-38 % decrease in plasma glucose, p<0.05). O(2) consumption, CO(2) production, RER, and energy expenditure were not altered by (Val(8))GLP-1-Glu-PAL therapy. Treatment with (Val(8))GLP-1-Glu-PAL resulted in a significant increase in BrdU-positive cells (1.3-fold, p<0.05) in the granule cell layer of the dentate gyrus. These data demonstrate that (Val(8))GLP-1-Glu-PAL is a long-acting GLP-1 peptide that significantly improves hippocampal neurogenesis, glucose homeostasis, and insulin secretion in high-fat-fed mice.

  16. Accelerator system and method of accelerating particles

    NASA Technical Reports Server (NTRS)

    Wirz, Richard E. (Inventor)

    2010-01-01

    An accelerator system and method that utilize dust as the primary mass flux for generating thrust are provided. The accelerator system can include an accelerator capable of operating in a self-neutralizing mode and having a discharge chamber and at least one ionizer capable of charging dust particles. The system can also include a dust particle feeder that is capable of introducing the dust particles into the accelerator. By applying a pulsed positive and negative charge voltage to the accelerator, the charged dust particles can be accelerated thereby generating thrust and neutralizing the accelerator system.

  17. Dispersion and interaction of graphene oxide in amorphous and semi-crystalline nano-composites: a PALS study

    NASA Astrophysics Data System (ADS)

    Maurer, Frans H. J.; Arza, Carlos R.

    2015-06-01

    The influence of dispersion and interaction of Graphene Oxide (GO) in semicrystalline Polyhydroxy butyrate (PHB) and glassy amorphous Poly(tBP-oda) is explored by Positron Annihilation Lifetime Spectroscopy (PALS). The ortho-Positronium lifetimes which represent the main free volume hole size of both polymers are mainly affected by the large differences in internal stresses built up by the shrinkage of the polymers during their preparation, restricted by the platelet structure of GO. The ortho-Positronium intensities, which represent the ortho-Positronium formation probabilities, suggest a strong dependency of on the dispersion of the nano-particles and their aspect ratio.

  18. Identification of Genes Involved in Indole-3-Acetic Acid Biosynthesis by Gluconacetobacter diazotrophicus PAL5 Strain Using Transposon Mutagenesis

    PubMed Central

    Rodrigues, Elisete P.; Soares, Cleiton de Paula; Galvão, Patrícia G.; Imada, Eddie L.; Simões-Araújo, Jean L.; Rouws, Luc F. M.; de Oliveira, André L. M.; Vidal, Márcia S.; Baldani, José I.

    2016-01-01

    Gluconacetobacter diazotrophicus is a beneficial nitrogen-fixing endophyte found in association with sugarcane plants and other important crops. Beneficial effects of G. diazotrophicus on sugarcane growth and productivity have been attributed to biological nitrogen fixation process and production of phytohormones especially indole-3-acetic acid (IAA); however, information about the biosynthesis and function of IAA in G. diazotrophicus is still scarce. Therefore, the aim of this work was to identify genes and pathways involved in IAA biosynthesis in this bacterium. In our study, the screening of two independent Tn5 mutant libraries of PAL5T strain using the Salkowski colorimetric assay revealed two mutants (Gdiaa34 and Gdiaa01), which exhibited 95% less indolic compounds than the parental strain when grown in LGIP medium supplemented with L-tryptophan. HPLC chromatograms of the wild-type strain revealed the presence of IAA and of the biosynthetic intermediates indole-3-pyruvic acid (IPyA) and indole-3-lactate (ILA). In contrast, the HPLC profiles of both mutants showed no IAA but only a large peak of non-metabolized tryptophan and low levels of IPyA and ILA were detected. Molecular characterization revealed that Gdiaa01 and Gdiaa34 mutants had unique Tn5 insertions at different sites within the GDI2456 open read frame, which is predicted to encode a L-amino acid oxidase (LAAO). GDI2456 (lao gene) forms a cluster with GDI2455 and GDI2454 ORFs, which are predicted to encode a cytochrome C and an RidA protein, respectively. RT-qPCR showed that transcript levels of lao. cccA, and ridA genes were reduced in the Gdiaa01 as compared to PAL5T. In addition, rice plants inoculated with Gdiaa01 showed significantly smaller root development (length, surface area, number of forks and tips) than those plants inoculated with PAL5T. In conclusion, our study demonstrated that G. diazotrophicus PAL5T produces IAA via the IPyA pathway in cultures supplemented with tryptophan and

  19. Alimini Lakes Project (PAL). Human-environment interaction during the Holocene in Mediterranean coastal wetlands

    NASA Astrophysics Data System (ADS)

    Balbo, Andrea; Primavera, Milena; Fiorentino, Girolamo; Simone, Oronzo; Caldara, Massimo; Quarta, Gianluca; Calcagnile, Lucio

    2010-05-01

    A diachronical understanding of the co-evolution of people and Mediterranean wetlands requires the combined study of archaeological and palaeoenvironmental records. By focusing on an extended chronology, and relying on the update of known and new archaeological and palaeonvironmental sequences, PAL investigates how the Alimini Lakes disctrict (Apulia, S Italy) has changed over the past 10ka (the Holocene), a period witnessing great climatic environmental and social change. Holocene climate change is amplified in coastal wetlands, greatly affecting hydrology vegetation and people. Likewise, socio-economical changes (e.g. the introduction of agriculture) play a fundamental role in the shaping of wet landscapes. Under the combined action of environmental and human factors, coastal wetlands are prone to rapid and drastic ecological shifts and constitute ideal locations for developing a geoarchaeological approach. The results of the first year of research are presented here and include (1) the visit, description and GPS positioning of previously and newly discovered archaeological areas (cave and open air sites), (2) sampling of two Holocene sedimentary sequences from the Alimini Lakes disctict, (3) the results of the preliminary analyses (including AMS radiocarbon dating) carried out on the samples. The relocation of new and previously found archaeological sites was necessary to overcome some confusions caused by the contrasting published information. Relocated archaeological sites were normalized in a GIS environment. Two main Pleistocene/Holocene palaeoenvironmental sequences were sampled within the Alimini Lakes district: (1) the Frassanito dune reference sequence, obtained from a portion of the coastal dune (up to 10 m high) bordering the trait of the Adriatic coast situated in front of the Alimini lakes, (2) the ALI G 1 core (9m long) sampled on the W shore of Alimini Grande Lake. The multiproxy study of these sedimentary sequences provides a record of Holocene

  20. Nitric oxide signals ROS scavenger-mediated enhancement of PAL activity in nitrogen-deficient Matricaria chamomilla roots: side effects of scavengers.

    PubMed

    Kovácik, Jozef; Klejdus, Borivoj; Backor, Martin

    2009-06-15

    Owing to the abundance of phenolic metabolites in plant tissue, their accumulation represents an important tool for stress protection. However, the regulation of phenolic metabolism is still poorly known. The regulatory role of reactive oxygen species (ROS) in the activity of phenylalanine ammonia-lyase (PAL) in nitrogen (N)-deficient chamomile roots treated for 24 h was studied using three ROS scavengers [dithiothreitol (DTT), salicylhydroxamic acid, and sodium benzoate]. Scavengers decreased the level of hydrogen peroxide and/or superoxide (and up-regulated ascorbate/guaiacol peroxidase and glutathione reductase), but, surprisingly, stimulated PAL activity. This up-regulation was correlated with increases in nitric oxide (NO) content, total soluble phenols, selected phenolic acids, and, partially, lignin (being expressed the most in DTT-exposed roots). We therefore tested the hypothesis that NO may be involved in these changes. Application of 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO) decreased PAL activity and the accumulation of soluble phenols in all treatments. Exogenous H(2)O(2) and NO also stimulated PAL activity and the accumulation of phenols. We conclude that NO, in addition to hydrogen peroxide, may regulate PAL activity during N deficiency. The anomalous effect of PTIO on NO content and possible mechanism of ROS scavenger-evoked NO increases in light of the current knowledge are also discussed.

  1. Mass spectrometry with accelerators.

    PubMed

    Litherland, A E; Zhao, X-L; Kieser, W E

    2011-01-01

    As one in a series of articles on Canadian contributions to mass spectrometry, this review begins with an outline of the history of accelerator mass spectrometry (AMS), noting roles played by researchers at three Canadian AMS laboratories. After a description of the unique features of AMS, three examples, (14)C, (10)Be, and (129)I are given to illustrate the methods. The capabilities of mass spectrometry have been extended by the addition of atomic isobar selection, molecular isobar attenuation, further ion acceleration, followed by ion detection and ion identification at essentially zero dark current or ion flux. This has been accomplished by exploiting the techniques and accelerators of atomic and nuclear physics. In 1939, the first principles of AMS were established using a cyclotron. In 1977 the selection of isobars in the ion source was established when it was shown that the (14)N(-) ion was very unstable, or extremely difficult to create, making a tandem electrostatic accelerator highly suitable for assisting the mass spectrometric measurement of the rare long-lived radioactive isotope (14)C in the environment. This observation, together with the large attenuation of the molecular isobars (13)CH(-) and (12)CH 2(-) during tandem acceleration and the observed very low background contamination from the ion source, was found to facilitate the mass spectrometry of (14)C to at least a level of (14)C/C ~ 6 × 10(-16), the equivalent of a radiocarbon age of 60,000 years. Tandem Accelerator Mass Spectrometry, or AMS, has now made possible the accurate radiocarbon dating of milligram-sized carbon samples by ion counting as well as dating and tracing with many other long-lived radioactive isotopes such as (10)Be, (26)Al, (36)Cl, and (129)I. The difficulty of obtaining large anion currents with low electron affinities and the difficulties of isobar separation, especially for the heavier mass ions, has prompted the use of molecular anions and the search for alternative

  2. Evaluation of CHROM-Pal medium for the isolation and direct identification of Candida dubliniensis in primary cultures from the oral cavity.

    PubMed

    Sahand, Ismail H; Maza, José L; Eraso, Elena; Montejo, Miguel; Moragues, María D; Aguirre, José M; Quindós, Guillermo; Pontón, José

    2009-11-01

    Candida albicans is the species most frequently isolated from oral specimens, but the recovery of other Candida species such as Candida dubliniensis is increasing. Differentiation of C. dubliniensis from C. albicans requires special tests and both species are misidentified in some studies. CHROM-Pal (CH-P) is a novel chromogenic medium used in our laboratory for differentiation between C. albicans and C. dubliniensis on the basis of colony colour and morphology, and chlamydospore production. The performance of CH-P and CHROMagar Candida (CAC) was compared for primary isolation and presumptive identification of yeasts from oral specimens from human immunodeficiency virus (HIV)-infected and uninfected individuals. The identification of Candida species on both media was compared with two reference identification methods (API ID 32 C and multiplex PCR). A total of 137/205 oral swabs (66.8 %) plated onto CH-P and CAC media were positive by culture and resulted in the growth of 171 isolates of Candida species on CH-P, whilst only 159 isolates grew on CAC. C. albicans was the most frequently isolated species in both groups of patients, followed by Candida parapsilosis in the HIV-negative group, and by C. dubliniensis in the HIV-infected group. The other Candida species isolated were Candida guilliermondii, Candida glabrata, Candida krusei, Candida tropicalis, Candida famata, Candida rugosa, Candida kefyr, Candida pelliculosa and Candida pulcherrima. The sensitivity and specificity for identifying C. albicans, C. krusei, C. tropicalis and C. dubliniensis on CH-P were over 98.5 %, always equal to or higher than those obtained when CAC was used. CH-P is a simple reliable medium for primary isolation and presumptive identification of yeast isolates from oral samples. The ability of CH-P to discriminate between C. dubliniensis and C. albicans was significantly higher (P <0.05) than that of CAC.

  3. Technology of magnetically driven accelerators

    NASA Astrophysics Data System (ADS)

    Birx, D. L.; Hawkins, S. A.; Poor, S. E.; Reginato, L. L.; Rogers, D., Jr.; Smith, M. W.

    1985-03-01

    The marriage of Induction Linac technology with Nonlinar Magnetic Modulators has produced some unique capabilities. It appears possible to produce electron beams with average currents measured in amperes, at gradients exceeding 1 MeV/meter, and with power efficiencies approaching 50%. A 2 MeV, 5 kA electron accelerator has been constructed at the Lawrence Livermore National Laboratory (LLNL) to demonstrate these concepts and to provide a test facility for high brightness sources. The pulse drive for the accelerator is based on magnetic pulse compressors with very high peak power capability, repetition rates exceeding a kilohertz and excellent reliability.

  4. Technology of magnetically driven accelerators

    SciTech Connect

    Brix, D.L.; Hawkins, S.A.; Poor, S.E.; Reginato, L.L.; Smith, M.W.

    1985-10-01

    The marriage of Induction Linac technology with Nonlinear Magnetic Modulators has produced some unique capabilities. It appears possible to produce electron beams with average currents measured in amperes, at gradients exceeding 1 MeV/meter, and with power efficiencies approaching 50%. A 2 MeV, 5 kA electron accelerator has been constructed at the Lawrence Livermore National Laboratory (LLNL) to demonstrate these concepts and to provide a test facility for high brightness sources. The pulse drive for the accelerator is based on state-of-the-art magnetic pulse compressors with very high peak power capability, repetition rates exceeding a kilohertz and excellent reliability.

  5. Technology of magnetically driven accelerators

    SciTech Connect

    Birx, D.L.; Hawkins, S.A.; Poor, S.E.; Reginato, L.L.; Rogers, D. Jr.; Smith, M.W.

    1985-03-26

    The marriage of Induction Linac technology with Nonlinear Magnetic Modulators has produced some unique capabilities. It appears possible to produce electron beams with average currents measured in amperes, at gradients exceeding 1 MeV/meter, and with power efficiencies approaching 50%. A 2 MeV, 5 kA electron accelerator has been constructed at the Lawrence Livermore National Laboratory (LLNL) to demonstrate these concepts and to provide a test facility for high brightness sources. The pulse drive for the accelerator is based on state-of-the-art magnetic pulse compressors with very high peak power capability, repetition rates exceeding a kilohertz and excellent reliability. 8 figs., 1 tab.

  6. STATUS OF THE DIELECTRIC WALL ACCELERATOR

    SciTech Connect

    Caporaso, G J; Chen, Y; Sampayan, S; Akana, G; Anaya, R; Blackfield, D; Carroll, J; Cook, E; Falabella, S; Guethlein, G; Harris, J; Hawkins, S; Hickman, B; Holmes, C; Horner, A; Nelson, S; Paul, A; Pearson, D; Poole, B; Richardson, R; Sanders, D; Selenes, K; Sullivan, J; Wang, L; Watson, J; Weir, J

    2009-04-22

    The dielectric wall accelerator (DWA) system being developed at the Lawrence Livermore National Laboratory (LLNL) uses fast switched high voltage transmission lines to generate pulsed electric fields on the inside of a high gradient insulating (HGI) acceleration tube. High electric field gradients are achieved by the use of alternating insulators and conductors and short pulse times. The system is capable of accelerating any charge to mass ratio particle. Applications of high gradient proton and electron versions of this accelerator will be discussed. The status of the developmental new technologies that make the compact system possible will be reviewed. These include, high gradient vacuum insulators, solid dielectric materials, photoconductive switches and compact proton sources.

  7. Acceleration modules in linear induction accelerators

    NASA Astrophysics Data System (ADS)

    Wang, Shao-Heng; Deng, Jian-Jun

    2014-05-01

    The Linear Induction Accelerator (LIA) is a unique type of accelerator that is capable of accelerating kilo-Ampere charged particle current to tens of MeV energy. The present development of LIA in MHz bursting mode and the successful application into a synchrotron have broadened LIA's usage scope. Although the transformer model is widely used to explain the acceleration mechanism of LIAs, it is not appropriate to consider the induction electric field as the field which accelerates charged particles for many modern LIAs. We have examined the transition of the magnetic cores' functions during the LIA acceleration modules' evolution, distinguished transformer type and transmission line type LIA acceleration modules, and re-considered several related issues based on transmission line type LIA acceleration module. This clarified understanding should help in the further development and design of LIA acceleration modules.

  8. Acidolytic cleavage of tris(alkoxy)benzylamide (PAL) "internal reference" amino acyl (IRAA) anchoring linkages: validation of accepted procedures in solid-phase peptide synthesis (SPPS).

    PubMed

    Albericio, F; Barany, G

    1993-03-01

    Under the normal conditions of acidolytic cleavage/deprotection of tris(alkoxy)benzylamide (PAL) anchoring linkages in Fmoc solid-phase peptide synthesis (SPPS), product release occurs by a straightforward single-step pathway. A recently reported cleavage of the NH--alpha CH bond of an amino acyl residue adjacent to PAL [see Int. J. Peptide Protein Res. 38, 146-153 (1991)] could not be confirmed in novel experiments incorporating a double "internal reference" amino acid (IRAA) design. The results of the present work revalidate the widely accepted application of IRAAs to monitor yields in SPPS, and confirm the reliability of PAL methodology for the preparation of C-terminal peptide amides.

  9. Identification of an eccentricity in the date/time metadata of a PAL MiniDV recording.

    PubMed

    Lacey, Douglas S; Koenig, Bruce E

    2008-11-01

    A Phase-Alternation Line (PAL) Mini Digital Video (MiniDV) recording and camcorder were provided by the Law Society of Singapore for forensic examination. During visual analyses of the submitted recording and a test recording produced on the submitted camcorder, the number of occurrences of each unique date/time stamp varied from the nominal value of 25 frames (the frame rate per second of PAL recordings), within a range of +/-3 frames. This embedded date/time information is recorded in the digital bit stream along with the video and audio information and can be optionally displayed during playback. These visual observations prompted detailed analyses of the digital metadata of the recordings which consisted of locating the portions of the bit stream associated with the date/time information, and then identifying their redundancy characteristics, data structure, and encoding protocol. Automated scripts were developed using digital data analysis software to locate, extract, convert, and count all of the unique date/time stamps, and to provide an easily-viewable output of the results. The application of the scripting process to both the submitted tape and the test recording produced on the submitted camcorder revealed that the date/time information on each exhibited a nonstandard but consistent timing pattern, which confirmed the visual observations and provided evidence that the submitted recording was consistent with having been produced on the submitted camcorder.

  10. The initial break-up of Pangæa elicited by Late Palæozoic deglaciation

    NASA Astrophysics Data System (ADS)

    Yeh, Meng-Wan; Shellnutt, J. Gregory

    2016-08-01

    The break-up of Pangæa was principally facilitated by tensional plate stress acting on pre-existing suture zones. The rifting of Pangæa began during the Early Permian along the southern Tethys margin and produced the lenticular-shaped continent known as Cimmeria. A mantle-plume model is ascribed to explain the rift-related volcanism but the NW-SE oriented Cimmerian rifts do not correlate well with pre-existing suture zones or ‘structural heterogeneities’ but appear to have a pertinent spatial and temporal association with Late Palæozoic glacial-interglacial cycles. Mantle potential temperature estimates of Cimmerian rift-related basalts (1410 °C ± 50 °C) are similar to ambient mantle conditions rather than an active mantle-plume rift as previously suggested. Moreover, we find that the distribution of glacial deposits shows significant temporal and spatial concurrence between the glacial retreat margins and rifting sites. We conclude that the location and timing of Cimmerian rifting resulted from the exploitation of structural heterogeneities within the crust that formed due to repeated glacial-interglacial cycles during the Late Palæozoic. Such effects of continental deglaciation helped to create the lenticular shape of Cimmeria and Neotethys Ocean suggesting that, in some instances, climate change may directly influence the location of rifting.

  11. Isolation and characterization of the anthocyanidin genes PAL, F3H and DFR of Scutellaria viscidula (Lamiaceae).

    PubMed

    Lei, W; Yao, R X; Kang, X H; Tang, S H; Qiao, A M; Sun, M

    2011-11-22

    Anthocyanidin is a group of flavonoid compounds used as a vegetable pigment and plays an important role in flower coloration and environmental adaptations of the Chinese ornamental plant Scutellaria viscidula. We determined the cDNA sequences of phenylalanine ammonia-lyase (SvPAL), flavanone 3-hydroxylase (SvF3H) and dihydroflavonol 4-reductase (SvDFR) genes in S. viscidula. Comparative analysis showed that the protein products of these three genes did not have a transit peptide at their N-terminal portion, which indicated that these enzymes were directly involved in the substrate conversion in the cytoplasmic matrix. Bioinformatic analysis further revealed that Svpal, Svf3h and Svdfr were the members of flavonoid biosynthetic genes with highly conserved motifs. Based on phylogenetic tree analysis, it appears that PAL, F3H or DFR from different plants might have originated from the same ancestor. This study can help to map and regulate the important stages involved in anthocyanidin biosynthesis by genetic engineering to diversify flower color and improve the ornamental value of S. viscidula.

  12. The initial break-up of Pangæa elicited by Late Palæozoic deglaciation

    PubMed Central

    Yeh, Meng-Wan; Shellnutt, J. Gregory

    2016-01-01

    The break-up of Pangæa was principally facilitated by tensional plate stress acting on pre-existing suture zones. The rifting of Pangæa began during the Early Permian along the southern Tethys margin and produced the lenticular-shaped continent known as Cimmeria. A mantle-plume model is ascribed to explain the rift-related volcanism but the NW-SE oriented Cimmerian rifts do not correlate well with pre-existing suture zones or ‘structural heterogeneities’ but appear to have a pertinent spatial and temporal association with Late Palæozoic glacial-interglacial cycles. Mantle potential temperature estimates of Cimmerian rift-related basalts (1410 °C ± 50 °C) are similar to ambient mantle conditions rather than an active mantle-plume rift as previously suggested. Moreover, we find that the distribution of glacial deposits shows significant temporal and spatial concurrence between the glacial retreat margins and rifting sites. We conclude that the location and timing of Cimmerian rifting resulted from the exploitation of structural heterogeneities within the crust that formed due to repeated glacial-interglacial cycles during the Late Palæozoic. Such effects of continental deglaciation helped to create the lenticular shape of Cimmeria and Neotethys Ocean suggesting that, in some instances, climate change may directly influence the location of rifting. PMID:27511791

  13. Physical Activity and Lymphedema (The PAL Trial): Assessing the safety of progressive strength training in breast cancer survivors

    PubMed Central

    Schmitz, Kathryn H.; Troxel, Andrea B.; Cheville, Andrea; Grant, Lorita L.; Bryan, Cathy J.; Gross, Cynthia; Lytle, Leslie A.; Ahmed, Rehana L.

    2009-01-01

    Lymphedema is a chronic and progressive long-term adverse effect of breast cancer treatment commonly defined by swelling of the affected arm. Current clinical guidelines indicate that women with and at risk for lymphedema should protect the affected arm from overuse. In clinical practice, this often translates into risk aversive guidance to avoid using the arm. This could lead to a disuse pattern that may increase the likelihood of injury from common activities of daily living. Further, such guidance poses an additional barrier to staying physically active, potentially translating to weight gain, which has been shown to be associated with worse clinical course for women with lymphedema. We hypothesize that a program of slowly progressive strength training with no upper limit on the amount of weight that may be lifted would gradually increase the physiologic capacity of the arm so that common activities represent a decreasing percentage of maximal capacity. Theoretically, this increased capacity should decrease the risk that daily activities put stress on the lymphatic system of the affected side. The Physical Activity and Lymphedema (PAL) Trial is a recently completed randomized controlled exercise intervention trial that recruited 295 breast cancer survivors (141 with lymphedema at study entry, 154 at risk for lymphedema at study entry). The purpose of this report is to provide detail regarding the study design, statistical design, and protocol of the PAL trial. PMID:19171204

  14. Localization and Function of Pals1-associated Tight Junction Protein in Drosophila Is Regulated by Two Distinct Apical Complexes.

    PubMed

    Sen, Arnab; Sun, Rui; Krahn, Michael P

    2015-05-22

    The transmembrane protein Crumbs (Crb) and its intracellular adaptor protein Pals1 (Stardust, Sdt in Drosophila) play a crucial role in the establishment and maintenance of apical-basal polarity in epithelial cells in various organisms. In contrast, the multiple PDZ domain-containing protein Pals1-associated tight junction protein (PATJ), which has been described to form a complex with Crb/Sdt, is not essential for apical basal polarity or for the stability of the Crb/Sdt complex in the Drosophila epidermis. Here we show that, in the embryonic epidermis, Sdt is essential for the correct subcellular localization of PATJ in differentiated epithelial cells but not during cellularization. Consistently, the L27 domain of PATJ is crucial for the correct localization and function of the protein. Our data further indicate that the four PDZ domains of PATJ function, to a large extent, in redundancy, regulating the function of the protein. Interestingly, the PATJ-Sdt heterodimer is not only recruited to the apical cell-cell contacts by binding to Crb but depends on functional Bazooka (Baz). However, biochemical experiments show that PATJ associates with both complexes, the Baz-Sdt and the Crb-Sdt complex, in the mature epithelium of the embryonic epidermis, suggesting a role of these two complexes for the function of PATJ during the development of Drosophila.

  15. Acceleration schedules for a recirculating heavy-ion accelerator

    SciTech Connect

    Sharp, W.M.; Grote, D.P.

    2002-05-01

    Recent advances in solid-state switches have made it feasible to design programmable, high-repetition-rate pulsers for induction accelerators. These switches could lower the cost of recirculating induction accelerators, such as the ''small recirculator'' at Lawrence Livermore National Laboratory (LLNL), by substantially reducing the number of induction modules. Numerical work is reported here to determine what effects the use of fewer pulsers at higher voltage would have on the beam quality of the LLNL small recirculator. Lattices with different numbers of pulsers are examined using the fluid/envelope code CIRCE, and several schedules for acceleration and compression are compared for each configuration. For selected schedules, the phase-space dynamics is also studied using the particle-in-cell code WARP3d.

  16. Space Radiation Effects Laboratory

    NASA Technical Reports Server (NTRS)

    1969-01-01

    The SREL User's Handbook is designed to provide information needed by those who plan experiments involving the accelerators at this laboratory. Thus the Handbook will contain information on the properties of the machines, the beam parameters, the facilities and services provided for experimenters, etc. This information will be brought up to date as new equipment is added and modifications accomplished. This Handbook is influenced by the many excellent models prepared at other accelerator laboratories. In particular, the CERN Synchrocyclotron User's Handbook (November 1967) is closely followed in some sections, since the SREL Synchrocyclotron is a duplicate of the CERN machine. We wish to thank Dr. E. G. Michaelis for permission to draw so heavily on his work, particularly in Section II of this Handbook. We hope that the Handbook will prove useful, and will welcome suggestions and criticism.

  17. APT accelerator. Topical report

    SciTech Connect

    Lawrence, G.; Rusthoi, D.

    1995-03-01

    The Accelerator Production of Tritium (APT) project, sponsored by Department of Energy Defense Programs (DOE/DP), involves the preconceptual design of an accelerator system to produce tritium for the nation`s stockpile of nuclear weapons. Tritium is an isotope of hydrogen used in nuclear weapons, and must be replenished because of radioactive decay (its half-life is approximately 12 years). Because the annual production requirements for tritium has greatly decreased since the end of the Cold War, an alternative approach to reactors for tritium production, based on a linear accelerator, is now being seriously considered. The annual tritium requirement at the time this study was undertaken (1992-1993) was 3/8 that of the 1988 goal, usually stated as 3/8-Goal. Continued reduction in the number of weapons in the stockpile has led to a revised (lower) production requirement today (March, 1995). The production requirement needed to maintain the reduced stockpile, as stated in the recent Nuclear Posture Review (summer 1994) is approximately 3/16-Goal, half the previous level. The Nuclear Posture Review also requires that the production plant be designed to accomodate a production increase (surge) to 3/8-Goal capability within five years, to allow recovery from a possible extended outage of the tritium plant. A multi-laboratory team, collaborating with several industrial partners, has developed a preconceptual APT design for the 3/8-Goal, operating at 75% capacity. The team has presented APT as a promising alternative to the reactor concepts proposed for Complex-21. Given the requirements of a reduced weapons stockpile, APT offers both significant safety, environmental, and production-fexibility advantages in comparison with reactor systems, and the prospect of successful development in time to meet the US defense requirements of the 21st Century.

  18. Quality of Life in Patients With Brain Metastases Using the EORTC QLQ-BN20+2 and QLQ-C15-PAL

    SciTech Connect

    Caissie, Amanda; Nguyen, Janet; Chen, Emily; Zhang Liying; Sahgal, Arjun; Clemons, Mark; Kerba, Marc; Arnalot, Palmira Foro; Danjoux, Cyril; Tsao, May; Barnes, Elizabeth; Holden, Lori; Danielson, Brita; Chow, Edward

    2012-07-15

    Purpose: The 20-item European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Brain Neoplasm (QLQ-BN20) is a validated quality-of-life (QOL) questionnaire for patients with primary brain tumors. The European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 15 Palliative (QLQ-C15-PAL) core palliative questionnaire is a 15-item version of the core 30-item QLQ-C30 and was developed to decrease the burden on patients with advanced cancer. The combination of the QLQ-BN20 and QLQ-C30 to assess QOL may be too burdensome for patients. The primary aim of this study was to assess QOL in patients before and after treatment for brain metastases using the QLQ-BN20+2 and QLQ-C15-PAL, a version of the QLQ-BN20 questionnaire with 2 additional questions assessing cognitive functioning that were not addressed in the QLQ-C15-PAL. Methods and Materials: Patients with brain metastases completed the QLQ-C15-PAL and QLQ-BN20+2 questionnaires to assess QOL before and 1 month after radiation. Linear regression analysis was used to assess changes in QOL scores over time, as well as to explore associations between the QLQ-BN20+2 and QLQ-C15-PAL scales, patient demographics, and clinical variables. Spearman correlation assessed associations between the QLQ-BN20+2 and QLQ-C15-PAL scales. Results: Among 108 patients, the majority (55%) received whole-brain radiotherapy only, with 65% of patients completing follow-up at 1 month after treatment. The most prominent symptoms at baseline were future uncertainty (QLQ-BN20+2) and fatigue (QLQ-C15-PAL). After treatment, significant improvement was seen for the QLQ-C15-PAL insomnia scale, as well as the QLQ-BN20+2 scales of future uncertainty, visual disorder, and concentration difficulty. Baseline Karnofsky Performance Status was negatively correlated to QLQ-BN20+2 motor dysfunction but positively related to QLQ-C15-PAL physical functioning and QLQ-BN20+2 cognitive functioning at

  19. EDITORIAL: Laser and plasma accelerators Laser and plasma accelerators

    NASA Astrophysics Data System (ADS)

    Bingham, Robert

    2009-02-01

    This special issue on laser and plasma accelerators illustrates the rapid advancement and diverse applications of laser and plasma accelerators. Plasma is an attractive medium for particle acceleration because of the high electric field it can sustain, with studies of acceleration processes remaining one of the most important areas of research in both laboratory and astrophysical plasmas. The rapid advance in laser and accelerator technology has led to the development of terawatt and petawatt laser systems with ultra-high intensities and short sub-picosecond pulses, which are used to generate wakefields in plasma. Recent successes include the demonstration by several groups in 2004 of quasi-monoenergetic electron beams by wakefields in the bubble regime with the GeV energy barrier being reached in 2006, and the energy doubling of the SLAC high-energy electron beam from 42 to 85 GeV. The electron beams generated by the laser plasma driven wakefields have good spatial quality with energies ranging from MeV to GeV. A unique feature is that they are ultra-short bunches with simulations showing that they can be as short as a few femtoseconds with low-energy spread, making these beams ideal for a variety of applications ranging from novel high-brightness radiation sources for medicine, material science and ultrafast time-resolved radiobiology or chemistry. Laser driven ion acceleration experiments have also made significant advances over the last few years with applications in laser fusion, nuclear physics and medicine. Attention is focused on the possibility of producing quasi-mono-energetic ions with energies ranging from hundreds of MeV to GeV per nucleon. New acceleration mechanisms are being studied, including ion acceleration from ultra-thin foils and direct laser acceleration. The application of wakefields or beat waves in other areas of science such as astrophysics and particle physics is beginning to take off, such as the study of cosmic accelerators considered

  20. Analysis of field-sampled, in-situ network, and PALS airborne soil moisture observations over SMAPVEX12

    NASA Astrophysics Data System (ADS)

    Adams, J. R.; Berg, A. A.; McNairn, H.; Cosh, M. H.

    2014-12-01

    The Soil Moisture Active Passive Validation Experiment in 2012 (SMAPVEX12) was conducted over an agricultural domain in southern Manitoba, Canada. The purpose of the campaign was to develop ground and airborne datasets for pre-launch validation of SMAP satellite soil moisture retrieval algorithms. Three key soil moisture datasets were collected in support of the campaign objectives: 1) intensive field sampling over (up to) 55 agricultural fields on 17 sampling days; 2) a continuously operated temporary in-situ network (> 30 stations) distributed over the domain; and 3) L-band microwave data from NASA's Passive Active L-band Sensor (PALS) onboard a Twin-Otter aircraft. This presentation addresses whether dense temporary in-situ networks can supplant intensive field-sampling during pre-/post-launch validation campaigns. SMAPVEX12 datasets are examined at the field and aircraft pixel (~800 m) scale, and at the domain scale. Preliminary results demonstrate that, at the field-scale, there is generally limited agreement between a single station and sampled data over its field. Over the duration of the campaign, the majority of temporary soil moisture stations have > 0.04 m3m-3 RMSE with sampled field data, suggesting that a single station has limited representativeness of an agricultural field. Furthermore, the in-situ stations and field-sampled data are compared with PALS generated soil moisture to assess differences in daily RMSE. For wet-periods, both ground datasets provide a comparable RMSE for the PALS estimate. Although for dry-periods, the difference in RMSE between the ground datasets becomes more significant (> 0.04 m3m-3). This is because the field-sampled data exhibit a sharper dry-down than the in-situ station measurements. However, at the domain scale there is strong agreement between the soil moisture datasets. Additional results describe the sources of variability affecting these soil moisture datasets and the statistical number of stations needed to

  1. Positron annihilation lifetime spectroscopy at a superconducting electron accelerator

    NASA Astrophysics Data System (ADS)

    Wagner, A.; Anwand, W.; Attallah, A. G.; Dornberg, G.; Elsayed, M.; Enke, D.; Hussein, A. E. M.; Krause-Rehberg, R.; Liedke, M. O.; Potzger, K.; Trinh, T. T.

    2017-01-01

    The Helmholtz-Zentrum Dresden-Rossendorf operates a superconducting linear accelerator for electrons with energies up to 35 MeV and average beam currents up to 1.6 mA. The electron beam is employed for production of several secondary beams including X-rays from bremsstrahlung production, neutrons, and positrons. The secondary positron beam after moderation feeds the Monoenergetic Positron Source (MePS) where positron annihilation lifetime (PALS) and positron annihilation Doppler-broadening experiments in materials science are performed in parallel. The adjustable repetition rate of the continuous-wave electron beams allows matching of the pulse separation to the positron lifetime in the sample under study. The energy of the positron beam can be set between 0.5 keV and 20 keV to perform depth resolved defect spectroscopy and porosity studies especially for thin films.

  2. The Gran Sasso Laboratory

    NASA Astrophysics Data System (ADS)

    Votano, L.

    2012-09-01

    The Gran Sasso underground laboratory is one of the four national laboratories run by the INFN (Istituto Nazionale di Fisica Nucleare). It is located under the Gran Sasso massif, in central Italy, between the cities of L'Aquila and Teramo, 120 km far from Rome. It is the largest underground laboratory for astroparticle physics in the world and the most advanced in terms of complexity and completeness of its infrastructures. The scientific program at the Gran Sasso National Laboratories (Laboratori Nazionali del Gran Sasso, LNGS)is mainly focused on astroparticle, particle and nuclear physics. The laboratory presently hosts many experiments as well as R&D activities, including world-leading research in the fields of solar neutrinos, accelerator neutrinos (CNGS neutrino beam from CERN to Gran Sasso), dark matter, neutrinoless double-beta decay and nuclear cross-section of astrophysical interest. Associate sciences like earth physics, biology and fundamental physics complement the activities. The laboratory is operated as an international science facility and hosts experiments whose scientific merit is assessed by an international advisory Scientific Committee. A review of the main experiments carried out at LNGS will be given, together with the most recent and relevant scientific results achieved.

  3. Measuring Early Spanish Literacy: Factor Structure and Measurement Invariance of the "Phonological Awareness Literacy Screening for Kindergarteners" in Spanish ("PALS español K")

    ERIC Educational Resources Information Center

    Huang, Francis L.; Ford, Karen L.; Invernizzi, Marcia; Fan, Xitao

    2013-01-01

    We investigated the latent factor structure of the "Phonological Awareness Literacy Screening for Kindergarteners" in Spanish ("PALS español K"). Participants included 590 Spanish-speaking, public-school kindergarteners from five states. Three theoretically-guided factor structures were measured and tested with one half of our…

  4. Developmental role of phenylalanine-ammonia-lyase (PAL) and cinnamate 4-hydroxylase (C4H) genes during adventitious rooting of Juglans regia L. microshoots.

    PubMed

    Cheniany, Monireh; Ganjeali, Ali

    2016-12-01

    Phenylalanine-ammonia-lyase and cinnamate-4-hydroxylase play important role in the phenylpropanoid pathway, which produces many biologically important secondary metabolites participating in normal plant development. Flavonol quercetin is the main representant of these compounds that has been identified in numerous Juglans spp. In this survey, the developmental expression patterns of PAL and C4H genes during in vitro rooting of two walnut cultivars 'Sunland' and 'Howard' was examined by RT-PCR. To understand the potential role in rooting, the changing pattern of endogenous content of quercetin was also analyzed by HPLC. The 'Sunland' with better capacity to root had more quercetin content during the "inductive phase" of rooting than 'Howard'. In each cultivar, the level of PAL transcripts showed the same behavior with the changing patterns of quercetin during root formation of microshoots. The positive correlation between the changes of quercetin and PAL-mRNA indicated that PAL gene may have an immediate effect on flavonoid pathway metabolites including quercetin. Although the behavioral change of C4H expression was similar in both cultivars during root formation (with significantly more level for 'Howard'), it was not coincide with the changes of quercerin concentrations. Our results showed that C4H function is important for the normal development, but its transcriptional regulation does not correlate with quercetin as an efficient phenolic compound for walnut rhizogenesis.

  5. "Did You Like Living in a Trailer? Why or Why Not?": Discourse and the Third Space in a Rural Pen Pal Exchange

    ERIC Educational Resources Information Center

    Eppley, Karen; Shannon, Patrick; Gilbert, Lauren K.

    2011-01-01

    This study describes efforts in a U.S. teacher education program to raise the teacher candidates' awareness of how place impacts schooling. The preservice teachers and second graders exchanged pen pal letters based on books set in contemporary rural America. The teacher candidates enacted four major discourses in the correspondence: personal,…

  6. "Do You Have a Brother? I Have Two!": The Nature of Questions Asked and Answered in Text-Focused Pen Pal Exchanges

    ERIC Educational Resources Information Center

    Hughes, Elizabeth M.; Evering, Lea; Malloy, Jacquelynn A.; Gambrell, Linda B.

    2014-01-01

    Authentic learning experiences are those in which students engage with texts as well as the behaviors of reading and writing within contexts of real-world use beyond traditional academic use. This study provides quantitative analysis of how students (n = 200) engaged with an adult pen pal in a shared literacy experience. Findings indicate that…

  7. Effects of phenylalanine ammonia lyase (PAL) knockdown on cell wall composition, biomass digestibility, and biotic and abiotic stress responses in Brachypodium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phenylalanine Ammonia Lyase (PAL) catalyzes the first step in the phenylpropanoid pathway in plants, controlling biosynthesis of a variety of structural and defense compounds including monolignols that polymerize into lignin. Gaps remain in our understanding of how genetic alterations to this pathwa...

  8. Characterization of pal-1, a common proviral insertion site in murine leukemia virus-induced lymphomas of c-myc and Pim-1 transgenic mice.

    PubMed Central

    Scheijen, B; Jonkers, J; Acton, D; Berns, A

    1997-01-01

    Insertional mutagenesis with Moloney murine leukemia virus (MoMLV) in c-myc and Pim-1 transgenic mice permits the identification of oncogenes that collaborate with the transgenes in lymphomagenesis. The recently identified common insertion site pal-1, in MoMLV-induced lymphomas, is located in a region in which several independent integration clusters are found: eis-1, gfi-1, and evi-5. Proviral insertions of MoMLV in the different integration clusters upregulate the transcriptional activity of the Gfi-1 gene, which is located within the pal-1 locus. The eis-1/pal-1/gfi-1/evi-5 locus serves as a target for MoMLV proviral insertions in pre-B-cell lymphomas of Emu-myc transgenic mice (20%) and in T-cell lymphomas of H-2K-myc (75%) and Emu-pim-1 (93%) transgenic mice. Many tumors overexpress both Gfi-1 as well as Myc and Pim gene family members, indicating that Gfi-1 collaborates with Myc and Pim in lymphomagenesis. Proviral integrations in the previously identified insertion site bmi-1 are, however, mutually exclusive with integrations in the eis-1/pal-1/gfi-1/evi-5 locus. This finding suggests that Bmi-1 and Gfi-1 belong to the same complementation group in lymphoid transformation. PMID:8985317

  9. Azimuthal Signature of Coincidental Brightness Temperature and Normalized Radar Cross-Section Obtained Using Airborne PALS Instrument

    NASA Technical Reports Server (NTRS)

    Colliander, Andreas; Kim, Seungbum; Yueh, Simon; Cosh, Mike; Jackson, Tom; Njoku, Eni

    2010-01-01

    Coincidental airborne brightness temperature (TB) and normalized radar-cross section (NRCS) measurements were carried out with the PALS (Passive and Active L- and S-band) instrument in the SMAPVEX08 (SMAP Validation Experiment 2008) field campaign. This paper describes results obtained from a set of flights which measured a field in 45(sup o) steps over the azimuth angle. The field contained mature soy beans with distinct row structure. The measurement shows that both TB and NRCS experience modulation effects over the azimuth as expected based on the theory. The result is useful in development and validation of land surface parameter forward models and retrieval algorithms, such as the soil moisture algorithm for NASA's SMAP (Soil Moisture Active and Passive) mission. Although the footprint of the SMAP will not be sensitive to the small resolution scale effects as the one presented in this paper, it is nevertheless important to understand the effects at smaller scale.

  10. Studying functional properties of hydrogel and silicone-hydrogel contact lenses with PALS, MIR and Raman spectroscopy.

    PubMed

    Filipecki, J; Sitarz, M; Kocela, A; Kotynia, K; Jelen, P; Filipecka, K; Gaweda, M

    2014-10-15

    Determination of free volume holes of the hydrogel and silicone-hydrogel polymer contact lenses were investigated. Two types of polymer contact lenses were used as materials: the first is a hydrogel contact lenses Proclear family (Omafilcon A), while the second is a silicone-hydrogel contact lens of the family Biofinity (Comfilcon A). Positron annihilation lifetime spectroscopy PALS was used to characterize geometrical sizes and fraction of the free volume holes in the investigated samples. There is a clear difference in the free volume sizes and their fractions between silicone-hydrogel and polymer hydrogel contact lenses which in turn are connected with oxygen permeability in these lenses. Apart from that, spectroscopic (middle infrared) MIR and Raman examinations were carried out in order to demonstrate the differences of the water content in the test contact lenses.

  11. PALS and DSC measurements in 8 MeV electron irradiated natural rubber filled with different fillers

    NASA Astrophysics Data System (ADS)

    Mandal, Arunava; Pan, Sandip; Roychowdhury, Anirban; Sengupta, Asmita

    2015-10-01

    The effect of high energy electron irradiation on the microstructure and thermal properties of natural rubber (NR) filled with different fillers at different concentrations are studied. The samples are irradiated with 8 MeV electron beam to a total dose of 100 KGy. The change in free volume size and specific heat due to addition of fillers and irradiation are studied using positron annihilation lifetime spectroscopy (PALS) and differential scanning calorimetry (DSC) respectively. The Positron lifetime spectra are de-convoluted into two components. The longer lived component (τo-Ps) signifies the pick-off annihilation of ortho-positronium (o-Ps) at free volume site which may be related to the radius of the free volume holes. It is observed that the specific heat (Cp) and free volume size are all affected by both irradiation and addition of fillers.

  12. Basic features of electromagnetic pulse generated in a laser-target chamber at 3-TW laser facility PALS

    NASA Astrophysics Data System (ADS)

    De Marco, M.; Pfeifer, M.; Krousky, E.; Krasa, J.; Cikhardt, J.; Klir, D.; Nassisi, V.

    2014-04-01

    We describe the radiofrequency emission taking place when 300 ps laser pulses irradiate various solid targets with an intensity of 1016 W/cm2. The emission of intense electromagnetic pulses was observed outside the laser target chamber by two loop antennas up to 1 GHz. Electromagnetic pulses can be 800 MHz transients, which decay from a peak electromagnetic field of E0 ≊ 7 kV/m and H0 ≊ 15 A/m. The occurrence of these electromagnetic pulses is associated with generation of hard x-rays with photon energies extending beyond 1 MeV. This contribution reports the first observation of this effect at the PALS facility.

  13. Late Neolithic vegetation history at the pile-dwelling site of Palù di Livenza (northeastern Italy

    NASA Astrophysics Data System (ADS)

    Pini, Roberta

    2004-12-01

    The Late Neolithic pile-dwelling of Palù di Livenza yielded archaeological remains typical of the Square Mouth Pottery and Lagozza Cultures. A palynological investigation reveals important changes in the vegetation due to anthropogenic pressure. Between ca. 6590 and 5960 cal. yr BP, dense oak wood forests with deciduous Quercus, Fagus and Corylus extended around the mire, with no signs of human impact. The establishment of the pile-dwelling, dated to ca. 5960 cal. yr BP, led to a strong reduction of forests, reclamation of wetlands, and expansion of herbaceous communities, with cultivated species, infestant weeds, nitrophilous and ruderal herbs, pastures and meadows. According to AMS dates and previous archaeological chronologies, the pile-dwelling persisted for about 700 years (from ca. 5960 to 5260 cal. yr BP). The history of the pile-dwelling after ca. 5260 cal. yr BP cannot be reconstructed because of recent contamination of the top part of the section. Rarefaction analysis was applied to estimate changes of palynological richness through time: the highest E(Tn) (between 56 and 69 taxa) are contemporaneous with the local development of the pile-dwelling. The comparison of pollen data with archaeobotanical evidence indicates that Fragaria vesca, Malus sylvestris, Papaver somniferum and Physalis alkekengi were gathered at some distance from the site and that Linum usitatissimum is strongly under-represented in pollen samples. Crop cultivation can be estimated for a radius of several hundred metres around the mire. Palù di Livenza is significant in the context of Neolithic archaeobotany of northern Italy and neighbouring countries. Copyright

  14. Laboratory Tests

    MedlinePlus

    Laboratory tests check a sample of your blood, urine, or body tissues. A technician or your doctor ... compare your results to results from previous tests. Laboratory tests are often part of a routine checkup ...

  15. Future accelerator technology

    SciTech Connect

    Sessler, A.M.

    1986-05-01

    A general discussion is presented of the acceleration of particles. Upon this foundation is built a categorization scheme into which all accelerators can be placed. Special attention is devoted to accelerators which employ a wake-field mechanism and a restricting theorem is examined. It is shown how the theorem may be circumvented. Comments are made on various acceleration schemes.

  16. ACCELERATION AND THE GIFTED.

    ERIC Educational Resources Information Center

    GIBSON, ARTHUR R.; STEPHANS, THOMAS M.

    ACCELERATION OF PUPILS AND SUBJECTS IS CONSIDERED A MEANS OF EDUCATING THE ACADEMICALLY GIFTED STUDENT. FIVE INTRODUCTORY ARTICLES PROVIDE A FRAMEWORK FOR THINKING ABOUT ACCELERATION. FIVE PROJECT REPORTS OF ACCELERATED PROGRAMS IN OHIO ARE INCLUDED. ACCELERATION IS NOW BEING REGARDED MORE FAVORABLY THAN FORMERLY, BECAUSE METHODS HAVE BEEN…

  17. Laser driven ion accelerator

    DOEpatents

    Tajima, Toshiki

    2005-06-14

    A system and method of accelerating ions in an accelerator to optimize the energy produced by a light source. Several parameters may be controlled in constructing a target used in the accelerator system to adjust performance of the accelerator system. These parameters include the material, thickness, geometry and surface of the target.

  18. Laser driven ion accelerator

    DOEpatents

    Tajima, Toshiki

    2006-04-18

    A system and method of accelerating ions in an accelerator to optimize the energy produced by a light source. Several parameters may be controlled in constructing a target used in the accelerator system to adjust performance of the accelerator system. These parameters include the material, thickness, geometry and surface of the target.

  19. Oak Ridge 25-MV tandem accelerator

    SciTech Connect

    Ziegler, N.F.; Richardson, E.G.; Mann, J.E.; Juras, R.C.; Jones, C.M.; Biggerstaff, J.A.; Benjamin, J.A.

    1981-01-01

    A new heavy-ion accelerator facility is nearing completion at the Oak Ridge National Laboratory. This paper presents a brief description of the scope and status of this project and a discussion of some aspects of the first operational experience with the 25 MV tandem accelerator which is being provided by the National Electrostatics Corporation (NEC) as a major component of the first phase of the facility.

  20. Accelerated/abbreviated test methods for predicting life of solar cell encapsulants to Jet Propulsion Laboratory California Institute of Technology for the encapsulation task of the low-cost solar array project

    NASA Technical Reports Server (NTRS)

    Kolyer, J. M.

    1978-01-01

    An important principle is that encapsulants should be tested in a total array system allowing realistic interaction of components. Therefore, micromodule test specimens were fabricated with a variety of encapsulants, substrates, and types of circuitry. One common failure mode was corrosion of circuitry and solar cell metallization due to moisture penetration. Another was darkening and/or opacification of encapsulant. A test program plan was proposed. It includes multicondition accelerated exposure. Another method was hyperaccelerated photochemical exposure using a solar concentrator. It simulates 20 year of sunlight exposure in a short period of one to two weeks. The study was beneficial in identifying some cost effective encapsulants and array designs.

  1. The Spallation Neutron Source accelerator system design

    NASA Astrophysics Data System (ADS)

    Henderson, S.; Abraham, W.; Aleksandrov, A.; Allen, C.; Alonso, J.; Anderson, D.; Arenius, D.; Arthur, T.; Assadi, S.; Ayers, J.; Bach, P.; Badea, V.; Battle, R.; Beebe-Wang, J.; Bergmann, B.; Bernardin, J.; Bhatia, T.; Billen, J.; Birke, T.; Bjorklund, E.; Blaskiewicz, M.; Blind, B.; Blokland, W.; Bookwalter, V.; Borovina, D.; Bowling, S.; Bradley, J.; Brantley, C.; Brennan, J.; Brodowski, J.; Brown, S.; Brown, R.; Bruce, D.; Bultman, N.; Cameron, P.; Campisi, I.; Casagrande, F.; Catalan-Lasheras, N.; Champion, M.; Champion, M.; Chen, Z.; Cheng, D.; Cho, Y.; Christensen, K.; Chu, C.; Cleaves, J.; Connolly, R.; Cote, T.; Cousineau, S.; Crandall, K.; Creel, J.; Crofford, M.; Cull, P.; Cutler, R.; Dabney, R.; Dalesio, L.; Daly, E.; Damm, R.; Danilov, V.; Davino, D.; Davis, K.; Dawson, C.; Day, L.; Deibele, C.; Delayen, J.; DeLong, J.; Demello, A.; DeVan, W.; Digennaro, R.; Dixon, K.; Dodson, G.; Doleans, M.; Doolittle, L.; Doss, J.; Drury, M.; Elliot, T.; Ellis, S.; Error, J.; Fazekas, J.; Fedotov, A.; Feng, P.; Fischer, J.; Fox, W.; Fuja, R.; Funk, W.; Galambos, J.; Ganni, V.; Garnett, R.; Geng, X.; Gentzlinger, R.; Giannella, M.; Gibson, P.; Gillis, R.; Gioia, J.; Gordon, J.; Gough, R.; Greer, J.; Gregory, W.; Gribble, R.; Grice, W.; Gurd, D.; Gurd, P.; Guthrie, A.; Hahn, H.; Hardek, T.; Hardekopf, R.; Harrison, J.; Hatfield, D.; He, P.; Hechler, M.; Heistermann, F.; Helus, S.; Hiatt, T.; Hicks, S.; Hill, J.; Hill, J.; Hoff, L.; Hoff, M.; Hogan, J.; Holding, M.; Holik, P.; Holmes, J.; Holtkamp, N.; Hovater, C.; Howell, M.; Hseuh, H.; Huhn, A.; Hunter, T.; Ilg, T.; Jackson, J.; Jain, A.; Jason, A.; Jeon, D.; Johnson, G.; Jones, A.; Joseph, S.; Justice, A.; Kang, Y.; Kasemir, K.; Keller, R.; Kersevan, R.; Kerstiens, D.; Kesselman, M.; Kim, S.; Kneisel, P.; Kravchuk, L.; Kuneli, T.; Kurennoy, S.; Kustom, R.; Kwon, S.; Ladd, P.; Lambiase, R.; Lee, Y. Y.; Leitner, M.; Leung, K.-N.; Lewis, S.; Liaw, C.; Lionberger, C.; Lo, C. C.; Long, C.; Ludewig, H.; Ludvig, J.; Luft, P.; Lynch, M.; Ma, H.; MacGill, R.; Macha, K.; Madre, B.; Mahler, G.; Mahoney, K.; Maines, J.; Mammosser, J.; Mann, T.; Marneris, I.; Marroquin, P.; Martineau, R.; Matsumoto, K.; McCarthy, M.; McChesney, C.; McGahern, W.; McGehee, P.; Meng, W.; Merz, B.; Meyer, R.; Meyer, R.; Miller, B.; Mitchell, R.; Mize, J.; Monroy, M.; Munro, J.; Murdoch, G.; Musson, J.; Nath, S.; Nelson, R.; Nelson, R.; O`Hara, J.; Olsen, D.; Oren, W.; Oshatz, D.; Owens, T.; Pai, C.; Papaphilippou, I.; Patterson, N.; Patterson, J.; Pearson, C.; Pelaia, T.; Pieck, M.; Piller, C.; Plawski, T.; Plum, M.; Pogge, J.; Power, J.; Powers, T.; Preble, J.; Prokop, M.; Pruyn, J.; Purcell, D.; Rank, J.; Raparia, D.; Ratti, A.; Reass, W.; Reece, K.; Rees, D.; Regan, A.; Regis, M.; Reijonen, J.; Rej, D.; Richards, D.; Richied, D.; Rode, C.; Rodriguez, W.; Rodriguez, M.; Rohlev, A.; Rose, C.; Roseberry, T.; Rowton, L.; Roybal, W.; Rust, K.; Salazer, G.; Sandberg, J.; Saunders, J.; Schenkel, T.; Schneider, W.; Schrage, D.; Schubert, J.; Severino, F.; Shafer, R.; Shea, T.; Shishlo, A.; Shoaee, H.; Sibley, C.; Sims, J.; Smee, S.; Smith, J.; Smith, K.; Spitz, R.; Staples, J.; Stein, P.; Stettler, M.; Stirbet, M.; Stockli, M.; Stone, W.; Stout, D.; Stovall, J.; Strelo, W.; Strong, H.; Sundelin, R.; Syversrud, D.; Szajbler, M.; Takeda, H.; Tallerico, P.; Tang, J.; Tanke, E.; Tepikian, S.; Thomae, R.; Thompson, D.; Thomson, D.; Thuot, M.; Treml, C.; Tsoupas, N.; Tuozzolo, J.; Tuzel, W.; Vassioutchenko, A.; Virostek, S.; Wallig, J.; Wanderer, P.; Wang, Y.; Wang, J. G.; Wangler, T.; Warren, D.; Wei, J.; Weiss, D.; Welton, R.; Weng, J.; Weng, W.-T.; Wezensky, M.; White, M.; Whitlatch, T.; Williams, D.; Williams, E.; Wilson, K.; Wiseman, M.; Wood, R.; Wright, P.; Wu, A.; Ybarrolaza, N.; Young, K.; Young, L.; Yourd, R.; Zachoszcz, A.; Zaltsman, A.; Zhang, S.; Zhang, W.; Zhang, Y.; Zhukov, A.

    2014-11-01

    The Spallation Neutron Source (SNS) was designed and constructed by a collaboration of six U.S. Department of Energy national laboratories. The SNS accelerator system consists of a 1 GeV linear accelerator and an accumulator ring providing 1.4 MW of proton beam power in microsecond-long beam pulses to a liquid mercury target for neutron production. The accelerator complex consists of a front-end negative hydrogen-ion injector system, an 87 MeV drift tube linear accelerator, a 186 MeV side-coupled linear accelerator, a 1 GeV superconducting linear accelerator, a 248-m circumference accumulator ring and associated beam transport lines. The accelerator complex is supported by ~100 high-power RF power systems, a 2 K cryogenic plant, ~400 DC and pulsed power supply systems, ~400 beam diagnostic devices and a distributed control system handling ~100,000 I/O signals. The beam dynamics design of the SNS accelerator is presented, as is the engineering design of the major accelerator subsystems.

  2. Fifty years of accelerator based physics at Chalk River

    SciTech Connect

    McKay, John W.

    1999-04-26

    The Chalk River Laboratories of Atomic Energy of Canada Ltd. was a major centre for Accelerator based physics for the last fifty years. As early as 1946, nuclear structure studies were started on Cockroft-Walton accelerators. A series of accelerators followed, including the world's first Tandem, and the MP Tandem, Superconducting Cyclotron (TASCC) facility that was opened in 1986. The nuclear physics program was shut down in 1996. This paper will describe some of the highlights of the accelerators and the research of the laboratory.

  3. ATLAS with CARIBU: A laboratory portrait

    SciTech Connect

    Pardo, Richard C.; Savard, Guy; Janssens, Robert V. F.

    2016-03-21

    The Argonne Tandem Linac Accelerator System (ATLAS) is the world's first superconducting accelerator for projectiles heavier than the electron. This unique system is a U.S. Department of Energy (DOE) national user research facility open to scientists from all over the world. Here, it is located within the Physics Division at Argonne National Laboratory and is one of five large scientific user facilities located at the laboratory.

  4. Thomas Jefferson National Accelerator Facility

    SciTech Connect

    Grames, Joseph; Higinbotham, Douglas; Montgomery, Hugh

    2010-09-08

    The Thomas Jefferson National Accelerator Facility (Jefferson Lab) in Newport News, Virginia, USA, is one of ten national laboratories under the aegis of the Office of Science of the U.S. Department of Energy (DOE). It is managed and operated by Jefferson Science Associates, LLC. The primary facility at Jefferson Lab is the Continuous Electron Beam Accelerator Facility (CEBAF) as shown in an aerial photograph in Figure 1. Jefferson Lab was created in 1984 as CEBAF and started operations for physics in 1995. The accelerator uses superconducting radio-frequency (srf) techniques to generate high-quality beams of electrons with high-intensity, well-controlled polarization. The technology has enabled ancillary facilities to be created. The CEBAF facility is used by an international user community of more than 1200 physicists for a program of exploration and study of nuclear, hadronic matter, the strong interaction and quantum chromodynamics. Additionally, the exceptional quality of the beams facilitates studies of the fundamental symmetries of nature, which complement those of atomic physics on the one hand and of high-energy particle physics on the other. The facility is in the midst of a project to double the energy of the facility and to enhance and expand its experimental facilities. Studies are also pursued with a Free-Electron Laser produced by an energy-recovering linear accelerator.

  5. A portable accelerator control toolkit

    SciTech Connect

    Watson, W.A. III

    1997-06-01

    In recent years, the expense of creating good control software has led to a number of collaborative efforts among laboratories to share this cost. The EPICS collaboration is a particularly successful example of this trend. More recently another collaborative effort has addressed the need for sophisticated high level software, including model driven accelerator controls. This work builds upon the CDEV (Common DEVice) software framework, which provides a generic abstraction of a control system, and maps that abstraction onto a number of site-specific control systems including EPICS, the SLAC control system, CERN/PS and others. In principle, it is now possible to create portable accelerator control applications which have no knowledge of the underlying and site-specific control system. Applications based on CDEV now provide a growing suite of tools for accelerator operations, including general purpose displays, an on-line accelerator model, beamline steering, machine status displays incorporating both hardware and model information (such as beam positions overlaid with beta functions) and more. A survey of CDEV compatible portable applications will be presented, as well as plans for future development.

  6. Laboratory Building

    SciTech Connect

    Herrera, Joshua M.

    2015-03-01

    This report is an analysis of the means of egress and life safety requirements for the laboratory building. The building is located at Sandia National Laboratories (SNL) in Albuquerque, NM. The report includes a prescriptive-based analysis as well as a performance-based analysis. Following the analysis are appendices which contain maps of the laboratory building used throughout the analysis. The top of all the maps is assumed to be north.

  7. Archimedes: Accelerator Reveals Ancient Text

    SciTech Connect

    Bergmann, Uwe

    2004-02-24

    Archimedes (287-212 BC), who is famous for shouting 'Eureka' (I found it) is considered one of the most brilliant thinkers of all times. The 10th-century parchment document known as the 'Archimedes Palimpsest' is the unique source for two of the great Greek's treatises. Some of the writings, hidden under gold forgeries, have recently been revealed at the Stanford Synchrotron Radiation Laboratory at SLAC. An intense x-ray beam produced in a particle accelerator causes the iron in original ink, which has been partly erased and covered, to send out a fluorescence glow. A detector records the signal and a digital image showing the ancient writings is produced. Please join us in this fascinating journey of a 1,000-year-old parchment from its origin in the Mediterranean city of Constantinople to a particle accelerator in Menlo Park.

  8. The Radiological Research Accelerator Facility

    SciTech Connect

    Hall, E.J.; Marino, S.A.

    1993-05-01

    The Radiological Research Accelerator Facility (RARAF) is based on a 4-MV Van de Graaff accelerator, which is used to generate a variety of well-characterized radiation beams for research in radiobiology, radiological physics, and radiation chemistry. It is part of the Center for Radiological Research (CRR) - formerly the Radiological Research Laboratory of Columbia University, and its operation is supported as a National Facility by the US Department of Energy (DOE). As such, RARAF is available to all potential users on an equal basis and scientists outside the CRR are encouraged to submit proposals for experiments at RARAF. The operation of the Van de Graaff is supported by the DOE, but the research projects themselves must be supported separately. This report provides a listing and brief description of experiments performed at RARAF during the May 1, 1992 through April 30, 1993.

  9. The Radiological Research Accelerator Facility

    SciTech Connect

    Hall, E.J.

    1992-05-01

    The Radiological Research Accelerator Facility (RARAF) is based on a 4-MV Van de Graaff accelerator, which is used to generate a variety of well-characterized radiation beams for research in radiobiology, radiological physics, and radiation chemistry. It is part of the Center for Radiological Research (CRR) -- formerly the Radiological Research Laboratory (RRL) -- of Columbia University, and its operation is supported as a National Facility by the US Department of Energy (DOE). As such, RARAF is available to all potential users on an equal basis, and scientists outside the CRR are encouraged to submit proposals for experiments at RARAF. The operation of the Van de Graaff is supported by the DOE, but the research projects themselves must be supported separately. Experiments performed from May 1991--April 1992 are described.

  10. The effect of acceleration on turbulent entrainment

    NASA Astrophysics Data System (ADS)

    Breidenthal, Robert E.

    2008-12-01

    A new class of self-similar turbulent flows is proposed, which exhibits dramatically reduced entrainment rates. Under strong acceleration, the rotation period of the large-scale vortices is forced to decrease linearly in time. In ordinary unforced turbulence, the rotation period always increases linearly with time, at least in the mean. However, by imposing an exponential acceleration on the flow, the vortex rotation period is forced to become the e-folding timescale of the acceleration. If the e-folding timescale itself decreases linearly in time, the forcing is 'super-exponential', characterized by an acceleration parameter α. Based on dimensional and heuristic arguments, a model suggests that the dissipation rate is an exponential function of α and the dimensions of the conserved quantity of the flow. Acceleration decreases the dissipation and entrainment rates in all canonical laboratory flows except for Rayleigh-Taylor. Experiments of exponential jets and super-exponential transverse jets are in accord with the model. As noted by Johari, acceleration is the only known means of affecting the entrainment rate of the far-field jet. Numerical simulations of Rayleigh-Taylor flow by Cook and Greenough are also consistent. In the limit of large acceleration, vortices do not move far before their rotation period changes substantially. In this sense, extreme acceleration corresponds to stationary vortices.

  11. Vacuum systems of linear accelerators of the NICA injection complex

    NASA Astrophysics Data System (ADS)

    Kosachev, V. V.; Bazanov, A. M.; Butenko, A. V.; Galimov, A. R.; Nesterov, A. V.; Pivin, R. V.; Smirnov, A. V.

    2016-12-01

    The NICA project, which includes several accelerators of charged particles, is under construction in the Laboratory of High Energy Physics, Joint Institute for Nuclear Research (JINR), Dubna. Obtaining the required vacuum conditions is one of the key points in implementing the project, because reaching the required ion lifetime at all stages of particle acceleration is what determines the effective luminosity of the experiments in the long run. Currently, modernization of the vacuum system of the injection complex of the LU-20 linear accelerator of light ions, one of oldest accelerators in the JINR, is being carried out and the new HILAC linear accelerator for the acceleration of gold ions in the collider mode of the NICA complex is being installed. At the end parts of the linear accelerators, the residual gas pressure must be approximately 10-5 Pa, which is determined by the maximum amplitude of the RF electric field used for the acceleration of ions.

  12. Accelerating Particles with Plasma

    ScienceCinema

    Litos, Michael; Hogan, Mark

    2016-07-12

    Researchers at SLAC explain how they use plasma wakefields to accelerate bunches of electrons to very high energies over only a short distance. Their experiments offer a possible path for the future of particle accelerators.

  13. Peak acceleration limiter

    NASA Technical Reports Server (NTRS)

    Chapman, C. P.

    1972-01-01

    Device is described that limits accelerations by shutting off shaker table power very rapidly in acceleration tests. Absolute value of accelerometer signal is used to trigger electronic switch which terminates test and sounds alarm.

  14. Linear Accelerator (LINAC)

    MedlinePlus

    ... equipment? How is safety ensured? What is this equipment used for? A linear accelerator (LINAC) is the ... Therapy (SBRT) . top of page How does the equipment work? The linear accelerator uses microwave technology (similar ...

  15. Accelerating Particles with Plasma

    SciTech Connect

    Litos, Michael; Hogan, Mark

    2014-11-05

    Researchers at SLAC explain how they use plasma wakefields to accelerate bunches of electrons to very high energies over only a short distance. Their experiments offer a possible path for the future of particle accelerators.

  16. Improved plasma accelerator

    NASA Technical Reports Server (NTRS)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  17. Accelerator Technology Division

    NASA Astrophysics Data System (ADS)

    1992-04-01

    In fiscal year (FY) 1991, the Accelerator Technology (AT) division continued fulfilling its mission to pursue accelerator science and technology and to develop new accelerator concepts for application to research, defense, energy, industry, and other areas of national interest. This report discusses the following programs: The Ground Test Accelerator Program; APLE Free-Electron Laser Program; Accelerator Transmutation of Waste; JAERI, OMEGA Project, and Intense Neutron Source for Materials Testing; Advanced Free-Electron Laser Initiative; Superconducting Super Collider; The High-Power Microwave Program; (Phi) Factory Collaboration; Neutral Particle Beam Power System Highlights; Accelerator Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Accelerator Design and Engineering; Radio-Frequency Technology; Free-Electron Laser Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operations.

  18. Pulsars and Acceleration Sites

    NASA Technical Reports Server (NTRS)

    Harding, Alice

    2008-01-01

    Rotation-powered pulsars are excellent laboratories for the studying particle acceleration as well as fundamental physics of strong gravity, strong magnetic fields and relativity. But even forty years after their discovery, we still do not understand their pulsed emission at any wavelength. I will review both the basic physics of pulsars as well as the latest developments in understanding their high-energy emission. Special and general relativistic effects play important roles in pulsar emission, from inertial frame-dragging near the stellar surface to aberration, time-of-flight and retardation of the magnetic field near the light cylinder. Understanding how these effects determine what we observe at different wavelengths is critical to unraveling the emission physics. Fortunately the Gamma-Ray Large Area Space Telescope (GLAST), with launch in May 2008 will detect many new gamma-ray pulsars and test the predictions of these models with unprecedented sensitivity and energy resolution for gamma-rays in the range of 30 MeV to 300 GeV.

  19. Accelerators, Colliders, and Snakes

    NASA Astrophysics Data System (ADS)

    Courant, Ernest D.

    2003-12-01

    The author traces his involvement in the evolution of particle accelerators over the past 50 years. He participated in building the first billion-volt accelerator, the Brookhaven Cosmotron, which led to the introduction of the "strong-focusing" method that has in turn led to the very large accelerators and colliders of the present day. The problems of acceleration of spin-polarized protons are also addressed, with discussions of depolarizing resonances and "Siberian snakes" as a technique for mitigating these resonances.

  20. An investigation of the effect of silicone oil on polymer intraocular lenses by means of PALS, FT-IR and Raman spectroscopies

    NASA Astrophysics Data System (ADS)

    Chamerski, Kordian; Lesniak, Magdalena; Sitarz, Maciej; Stopa, Marcin; Filipecki, Jacek

    2016-10-01

    The effect of the polydimethylsiloxane (PDMS) based silicone oil, that is widely used in vitreoretinal surgery, on internal structures of the polymer intraocular lenses was investigated. The effect of PDMS was studied on the polymethyl methacrylate (PMMA) rigid lenses and poly(2-hydroxyethyl methacrylate) (PHEMA) flexible lenses. The research was carried out by means of the positron lifetime spectroscopy (PALS) as well as the infrared spectroscopy (FT-IR) and the Raman spectroscopy (RS). The studies involving the use of PALS and FT-IR methods have revealed that the PHEMA based lenses absorbed, whereas the PMMA lenses did not absorb, silicone oil. The results obtained with the use of the RS method were inconclusive, probably due to the too low intensity of the characteristic PDMS bands. The evidence from this study was discussed in terms of physics and related to the clinical use of both silicone oil and intraocular lenses.

  1. Acceleration: It's Elementary

    ERIC Educational Resources Information Center

    Willis, Mariam

    2012-01-01

    Acceleration is one tool for providing high-ability students the opportunity to learn something new every day. Some people talk about acceleration as taking a student out of step. In actuality, what one is doing is putting a student in step with the right curriculum. Whole-grade acceleration, also called grade-skipping, usually happens between…

  2. Angular Acceleration without Torque?

    ERIC Educational Resources Information Center

    Kaufman, Richard D.

    2012-01-01

    Hardly. Just as Robert Johns qualitatively describes angular acceleration by an internal force in his article "Acceleration Without Force?" here we will extend the discussion to consider angular acceleration by an internal torque. As we will see, this internal torque is due to an internal force acting at a distance from an instantaneous center.

  3. Accelerated test design

    NASA Technical Reports Server (NTRS)

    Mcdermott, P. P.

    1980-01-01

    The design of an accelerated life test program for electric batteries is discussed. A number of observations and suggestions on the procedures and objectives for conducting an accelerated life test program are presented. Equations based on nonlinear regression analysis for predicting the accelerated life test parameters are discussed.

  4. Packing and mobility of hydrocarbon chains in phospholipid lyotropic liquid crystalline lamellar phases and liposomes: characterisation by positron annihilation lifetime spectroscopy (PALS).

    PubMed

    Dong, Aurelia W; Fong, Celesta; Waddington, Lynne J; Hill, Anita J; Boyd, Ben J; Drummond, Calum J

    2015-01-07

    Lipid lamellar mesophases and their colloidal dispersions (liposomes) are increasingly being deployed in vivo as drug delivery vehicles, and also as models of biological membranes in fundamental biophysics studies. The permeability and diffusion of small molecules such as drugs is accommodated by a change in local curvature and molecular packing (mesophase behaviour) of the bilayer membrane molecules. Positron annihilation lifetime spectroscopy (PALS) is capable of providing in situ molecular level information on changes in free volume and void space arising from such changes in a non-perturbative manner. In this work PALS was used to systematically characterise the temperature-induced melting transitions (Tm) of saturated and unsaturated phospholipid-water systems while systematically varying lipid chain length, as both bulk lamellar mesophase and as aqueous colloidal dispersions (liposomes). A four-component fit of the data was used that provides separate PALS lifetimes for the aqueous (τ3) and organic domains (τ4). The oPs lifetime (τ4), for the lamellar phases of DSPC (C18:0), DPPC (C16:0), DMPC (C14:0) and DLPC (C12:0) was found to be independent of chain length, with characteristic lifetime value τ4 ∼ 3.4 ns. τ4 is consistently larger in the dispersed liposomes compared to the bulk mesophases, suggesting that the hydrocarbon chains are more mobile. The use of contemporary and consistent analytical approaches as described in this study is the key to future deployment of PALS to interrogate the in situ influence of drugs on membrane and cellular microenvironments.

  5. D-Ala2-GIP-glu-PAL is neuroprotective in a chronic Parkinson's disease mouse model and increases BNDF expression while reducing neuroinflammation and lipid peroxidation.

    PubMed

    Li, Yanwei; Liu, WeiZhen; Li, Lin; Hölscher, Christian

    2017-02-15

    Type 2 diabetes mellitus (T2DM) is a risk factor for Parkinson's disease (PD). Therefore, treatment to improve insulin resistance in T2DM may be useful for PD patients. Glucose dependent insulinotropic polypeptide (GIP) is a member of the incretin hormone family that can promote insulin release and improve insulin resistance. Several GIP analogues have been developed as potential treatments for T2DM. We had shown previously that D-Ala2-GIP-glu-PAL, a novel long-acting GIP analogue, can play a neuroprotective role in the PD mouse model induced by acute MPTP injection. The drug reduced damage to the dopaminergic neurons and increased CREB-mediated Bcl-2 expression to prevent apoptosis and reduced chronic inflammation in the brain. In the present study, we further tested the effects of chronic treatment by D-Ala2-GIP-glu-PAL in a chronic PD mouse model induced by MPTP (25mg/kg ip.) combination with probenecid (250mg/kg ip.) injection for 5 weeks. The results demonstrated that chronic treatment with D-Ala2-GIP-glu-PAL inhibits MPTP -induced Parkinsonism-like motor disorders in mice, and that the drug prevents dopaminergic neuronal loss in the substantia nigra pars compacta (SNpc). Moreover, D-Ala2-GIP-glu-PAL also inhibited the increased levels of expression of α-synuclein in the SNpc and striatum induced by MPTP. Furthermore, drug treatment reduced chronic neuroinflammation, oxidative stress and lipid peroxidation, and increased the expression of BDNF. These findings show that GIP signaling is neuroprotective and holds promise as a novel treatment of PD.

  6. The charged particle accelerators subsystems modeling

    NASA Astrophysics Data System (ADS)

    Averyanov, G. P.; Kobylyatskiy, A. V.

    2017-01-01

    Presented web-based resource for information support the engineering, science and education in Electrophysics, containing web-based tools for simulation subsystems charged particle accelerators. Formulated the development motivation of Web-Environment for Virtual Electrophysical Laboratories. Analyzes the trends of designs the dynamic web-environments for supporting of scientific research and E-learning, within the framework of Open Education concept.

  7. Maastrichtian-Early Eocene litho-biostratigraphy and palægeography of the northern Gulf of Suez region, Egypt

    NASA Astrophysics Data System (ADS)

    Scheibner, C.; Marzouk, A. M.; Kuss, J.

    2001-02-01

    The Maastrichtian-Lower Eocene sediments on both sides of the northern Gulf of Suez can be subdivided into eight formal formations (including one group) and one informal formation that are described in detail. These lithostratigraphic units reflect three different environmental regimes of deposition or non-deposition. The first regime is characterised by uplift and erosion or non-deposition resulting mostly from the uplift of the Northern Galala/Wadi Araba structure, a branch of the Syrian Arc Foldbelt. The shallow water carbonate platform and slope deposits of the Late Campanian-Maastrichtian St Anthony Formation and the Paleocene-Lower Eocene Southern Galala and Garra Formations represent the second regime and are found north and south of the Northern Galala/Wadi Araba High. The third regime is represented by basinal chalks, marls and shales of the Maastrichtian Sudr Formation and of the Paleocene-Eocene Dakhla, Tarawan and Esna Formations, the Dakhla/Tarawan/Esna informal formation and the Thebes Group. The distribution and lateral interfingering of the above mentioned environmental regimes reflect different vertical movements, changing basin morphology, sea level changes and progradation of shallow water sediments and is illustrated on 11 palæogeographic maps.

  8. Separating Hazardous Aerosols from Ambient Aerosols: Role of Fluorescence-Spectral Determination, Aerodynamic Deflector and Pulse Aerodynamic Localizer (PAL)

    SciTech Connect

    Pan, Yong-Le; Cobler, Patrick J.; Rhodes, Scott A.; Halverson, Justin; Chang, Richard K.

    2005-08-22

    An aerosol deflection technique based on the single-shot UV-laser-induced fluorescence spectrum from a flowing particle is presented as a possible front-end bio-aerosol/hazardous-aerosol sensor/identifier. Cued by the fluorescence spectra, individual flowing bio-aerosol particles (1-10 {micro}m in diameter) have been successfully deflected from a stream of ambient aerosols. The electronics needed to compare the fluorescence spectrum of a particular particle with that of a pre-determined fluorescence spectrum are presented in some detail. The deflected particles, with and without going through a funnel for pulse aerodynamic localization (PAL), were collected onto a substrate for further analyses. To demonstrate how hazardous materials can be deflected, TbCl{sub 3} {center_dot} 6H{sub 2}O (a simulant material for some chemical forms of Uranium Oxide) aerosol particles (2 {micro}m in diameter) mixed with Arizona road dust was separated and deflected with our system.

  9. Individual information beam broadcasting system using a PAL-SLM based CGH beam former for the location based information services

    NASA Astrophysics Data System (ADS)

    Osawa, Shunichi; Itoh, Hideo; Nakamura, Yoshiyuki; Nishimura, Takuichi; Lin, Xin; Tokuda, Masamitsu

    2006-01-01

    As an implementation of ubiquitous information service environments, we have been researching location-based information service systems at indoor and short distance area. The system should provide adequate information services, which fit the user's attributes, such as language, knowledge level and the volume of information, what is so-called "Right now, Here, and for Me" information services. Keeping privacy and security of the user is an important issue. Spatial optical communication technique is used for the system because the technique is easy to implement a location- and direction-based communication system. Information broadcasting in an area can be realized by an omnidirectional modulated light emission. However, the omnidirectional beam causes spill out of secure information to others, and has lower energy conservation than a focused beam communication. In this paper, a new spatial optical information broadcasting system, which can focus modulated beams only to intended users. CGH (Computer Generated Hologram) technique on a SLM (Spatial Light Modulator) is proposed and demonstrated. The system is composed of a PAL-SLM (Parallel Aligned Nematic Liquid Crystal Spatial Light Modulator), an eye-safe semiconductor laser or a semiconductor laser pumped YAG laser for the beam emitter, and an infrared video camera with an infrared LED illuminator for user locator. Experimental results of beam deflecting characteristics are described on beam uniformity, deflecting angle and the enhancement, communication characteristics, and real time tracking of user with a corner-reflecting sheet.

  10. Biological assessments for the low energy demonstration accelerator, 1996

    SciTech Connect

    Cross, S.

    1997-03-01

    This report discusses the biological impact to the area around the Los Alamos National Laboratory of the Low Energy Demonstration Accelerator. In particular the impact to the soils, water quality, vegetation, and wildlife are discussed.

  11. Don't Use Airtracks to Measure Gravity Acceleration.

    ERIC Educational Resources Information Center

    Kluk, Edward; Lopez, John L.

    1992-01-01

    Presents one way, using simple materials available in hardware stores, to obtain accurate measurements of gravity acceleration in student laboratories. Analyzes a time-of-flight measuring scheme and discusses the experimental arrangements to make the measurements. (MDH)

  12. Effects of PHENYLALANINE AMMONIA LYASE (PAL) knockdown on cell wall composition, biomass digestibility, and biotic and abiotic stress responses in Brachypodium

    SciTech Connect

    Cass, Cynthia L.; Peraldi, Antoine; Dowd, Patrick F.; Mottiar, Yaseen; Santoro, Nicholas; Karlen, Steven D.; Bukhman, Yury V.; Foster, Cliff E.; Thrower, Nick; Bruno, Laura C.; Moskvin, Oleg V.; Johnson, Eric T.; Willhoit, Megan E.; Phutane, Megha; Ralph, John; Mansfield, Shawn D.; Nicholson, Paul; Sedbrook, John C.

    2015-06-19

    The phenylpropanoid pathway in plants synthesizes a variety of structural and defence compounds, and is an important target in efforts to reduce cell wall lignin for improved biomass conversion to biofuels. Little is known concerning the trade-offs in grasses when perturbing the function of the first gene family in the pathway, PHENYLALANINE AMMONIA LYASE (PAL). Therefore, PAL isoforms in the model grass Brachypodium distachyon were targeted, by RNA interference (RNAi), and large reductions (up to 85%) in stem tissue transcript abundance for two of the eight putative BdPAL genes were identified. The cell walls of stems of BdPAL-knockdown plants had reductions of 43% in lignin and 57% in cell wall-bound ferulate, and a nearly 2-fold increase in the amounts of polysaccharide-derived carbohydrates released by thermochemical and hydrolytic enzymic partial digestion. PAL-knockdown plants exhibited delayed development and reduced root growth, along with increased susceptibilities to the fungal pathogens Fusarium culmorum and Magnaporthe oryzae. Surprisingly, these plants generally had wild-type (WT) resistances to caterpillar herbivory, drought, and ultraviolet light. RNA sequencing analyses revealed that the expression of genes associated with stress responses including ethylene biosynthesis and signalling were significantly altered in PAL knocked-down plants under non-challenging conditions. These data reveal that, although an attenuation of the phenylpropanoid pathway increases carbohydrate availability for biofuel, it can adversely affect plant growth and disease resistance to fungal pathogens. Lastly, the data identify notable differences between the stress responses of these monocot pal mutants versus Arabidopsis (a dicot) pal mutants and provide insights into the challenges that may arise when deploying phenylpropanoid pathway-altered bioenergy crops.

  13. Industrialization of Superconducting RF Accelerator Technology

    NASA Astrophysics Data System (ADS)

    Peiniger, Michael; Pekeler, Michael; Vogel, Hanspeter

    2012-01-01

    Superconducting RF (SRF) accelerator technology has basically existed for 50 years. It took about 20 years to conduct basic R&D and prototyping at universities and international institutes before the first superconducting accelerators were built, with industry supplying complete accelerator cavities. In parallel, the design of large scale accelerators using SRF was done worldwide. In order to build those accelerators, industry has been involved for 30 years in building the required cavities and/or accelerator modules in time and budget. To enable industry to supply these high tech components, technology transfer was made from the laboratories in the following three regions: the Americas, Asia and Europe. As will be shown, the manufacture of the SRF cavities is normally accomplished in industry whereas the cavity testing and module assembly are not performed in industry in most cases, yet. The story of industrialization is so far a story of customized projects. Therefore a real SRF accelerator product is not yet available in this market. License agreements and technology transfer between leading SRF laboratories and industry is a powerful tool for enabling industry to manufacture SRF components or turnkey superconducting accelerator modules for other laboratories and users with few or no capabilities in SRF technology. Despite all this, the SRF accelerator market today is still a small market. The manufacture and preparation of the components require a range of specialized knowledge, as well as complex and expensive manufacturing installations like for high precision machining, electron beam welding, chemical surface preparation and class ISO4 clean room assembly. Today, the involved industry in the US and Europe comprises medium-sized companies. In Japan, some big enterprises are involved. So far, roughly 2500 SRF cavities have been built by or ordered from industry worldwide. Another substantial step might come from the International Linear Collider (ILC) project

  14. The LLNL multi-user tandem laboratory

    NASA Astrophysics Data System (ADS)

    Davis, J. C.

    1989-04-01

    An FN tandem laboratory, cofunded by several Lawrence Livermore National Laboratory Divisions, Sandia Livermore, and the University of California Regents, is now operational at Livermore. The accelerator, formerly the University of Washington injector, has been upgraded with SF 6, Dowlish tubes, and a NEC pelletron charging system. A conventional duoplasmatron, a tritium source, and two Cs sputtering sources will be fielded on the accelerator. Pulsed beams will be available from two source positions. The laboratory has been designed to accommodate up to 19 experimental positions with excellent optics and working vacuum. The facility is unshielded with both accelerator and radiological systems under the control of a distributed microprocessor system. Research activities at the tandem include nuclear physics and astrophysics, materials science and characterization programs, and accelerator mass spectrometry for archaeology, biomedical, environmental and geoscience investigators.

  15. Fiber Accelerating Structures

    SciTech Connect

    Hammond, Andrew P.; /Reed Coll. /SLAC

    2010-08-25

    One of the options for future particle accelerators are photonic band gap (PBG) fiber accelerators. PBG fibers are specially designed optical fibers that use lasers to excite an electric field that is used to accelerate electrons. To improve PBG accelerators, the basic parameters of the fiber were tested to maximize defect size and acceleration. Using the program CUDOS, several accelerating modes were found that maximized these parameters for several wavelengths. The design of multiple defects, similar to having closely bound fibers, was studied to find possible coupling or the change of modes. The amount of coupling was found to be dependent on distance separated. For certain distances accelerating coupled modes were found and examined. In addition, several non-periodic fiber structures were examined using CUDOS. The non-periodic fibers produced several interesting results and promised more modes given time to study them in more detail.

  16. High brightness electron accelerator

    DOEpatents

    Sheffield, Richard L.; Carlsten, Bruce E.; Young, Lloyd M.

    1994-01-01

    A compact high brightness linear accelerator is provided for use, e.g., in a free electron laser. The accelerator has a first plurality of acclerating cavities having end walls with four coupling slots for accelerating electrons to high velocities in the absence of quadrupole fields. A second plurality of cavities receives the high velocity electrons for further acceleration, where each of the second cavities has end walls with two coupling slots for acceleration in the absence of dipole fields. The accelerator also includes a first cavity with an extended length to provide for phase matching the electron beam along the accelerating cavities. A solenoid is provided about the photocathode that emits the electons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electons as the electrons enter the first cavity.

  17. Accelerator and Fusion Research Division: Summary of activities, 1986

    SciTech Connect

    Not Available

    1987-04-15

    This report contains a summary of activities at the Lawrence Berkeley Laboratory's Accelerator and Fusion Research Division for the year 1986. Topics and facilities investigated in individual papers are: 1-2 GeV Synchrotron Radiation Source, the Center for X-Ray Optics, Accelerator Operations, High-Energy Physics Technology, Heavy-Ion Fusion Accelerator Research and Magnetic Fusion Energy. Six individual papers have been indexed separately. (LSP)

  18. Multipactor Physics, Acceleration, and Breakdown in Dielectric-Loaded Accelerating Structures

    SciTech Connect

    Fischer, Richard P.; Gold, Steven H.

    2016-07-01

    The objective of this 3-year program is to study the physics issues associated with rf acceleration in dielectric-loaded accelerating (DLA) structures, with a focus on the key issue of multipactor loading, which has been found to cause very significant rf power loss in DLA structures whenever the rf pulsewidth exceeds the multipactor risetime (~10 ns). The experiments are carried out in the X-band magnicon laboratory at the Naval Research Laboratory (NRL) in collaboration with Argonne National Laboratory (ANL) and Euclid Techlabs LLC, who develop the test structures with support from the DoE SBIR program. There are two main elements in the research program: (1) high-power tests of DLA structures using the magnicon output (20 MW @11.4 GHz), and (2) tests of electron acceleration in DLA structures using relativistic electrons from a compact X-band accelerator. The work during this period has focused on a study of the use of an axial magnetic field to suppress multipactor in DLA structures, with several new high power tests carried out at NRL, and on preparation of the accelerator for the electron acceleration experiments.

  19. Federal laboratories for the 21st century

    SciTech Connect

    Gover, J.; Huray, P.G.

    1998-04-01

    Federal laboratories have successfully filled many roles for the public; however, as the 21st Century nears it is time to rethink and reevaluate how Federal laboratories can better support the public and identify new roles for this class of publicly-owned institutions. The productivity of the Federal laboratory system can be increased by making use of public outcome metrics, by benchmarking laboratories, by deploying innovative new governance models, by partnerships of Federal laboratories with universities and companies, and by accelerating the transition of federal laboratories and the agencies that own them into learning organizations. The authors must learn how government-owned laboratories in other countries serve their public. Taiwan`s government laboratory, Industrial Technology Research Institute, has been particularly successful in promoting economic growth. It is time to stop operating Federal laboratories as monopoly institutions; therefore, competition between Federal laboratories must be promoted. Additionally, Federal laboratories capable of addressing emerging 21st century public problems must be identified and given the challenge of serving the public in innovative new ways. Increased investment in case studies of particular programs at Federal laboratories and research on the public utility of a system of Federal laboratories could lead to increased productivity of laboratories. Elimination of risk-averse Federal laboratory and agency bureaucracies would also have dramatic impact on the productivity of the Federal laboratory system. Appropriately used, the US Federal laboratory system offers the US an innovative advantage over other nations.

  20. Measurement of Coriolis Acceleration with a Smartphone

    NASA Astrophysics Data System (ADS)

    Shakur, Asif; Kraft, Jakob

    2016-05-01

    Undergraduate physics laboratories seldom have experiments that measure the Coriolis acceleration. This has traditionally been the case owing to the inherent complexities of making such measurements. Articles on the experimental determination of the Coriolis acceleration are few and far between in the physics literature. However, because modern smartphones come with a raft of built-in sensors, we have a unique opportunity to experimentally determine the Coriolis acceleration conveniently in a pedagogically enlightening environment at modest cost by using student-owned smartphones. Here we employ the gyroscope and accelerometer in a smartphone to verify the dependence of Coriolis acceleration on the angular velocity of a rotatingtrack and the speed of the sliding smartphone.

  1. Pulsed power accelerators for particle beam fusion

    SciTech Connect

    Martin, T.H.; Barr, G.W.; VanDevender, J.P.; White, R.A.; Johnson, D.L.

    1980-01-01

    Sandia National Laboratories is completing the construction phase of the Particle Beam Fusion Accelerator-I (PBFA-I). Testing of the 36 module, 30 TW, 1 MJ output accelerator is in the initial stages. The 4 MJ, PBFA Marx generator has provided 3.6 MA into water-copper sulfate load resistors with a spread from first to last Marx firing between 15 to 25 ns and an output power of 5.7 TW. This accelerator is a modular, lower voltage, pulsed power device that is capable of scaling to power levels exceeding 100 TW. The elements of the PBFA technology and their integration into an accelerator system for particle beam fusion will be discussed.

  2. Accelerator and Fusion Research Division 1989 summary of activities

    SciTech Connect

    Not Available

    1990-06-01

    This report discusses the research being conducted at Lawrence Berkeley Laboratory's Accelerator and Fusion Research Division. The main topics covered are: heavy-ion fusion accelerator research; magnetic fusion energy; advanced light source; center for x-ray optics; exploratory studies; high-energy physics technology; and bevalac operations.

  3. Laboratory accreditation.

    PubMed

    Bradway, D E; Siegelman, F L

    1994-09-01

    An investigation of alleged data fraud at a pesticide analytical laboratory led EPA to take a closer look at the Good Laboratory Practice (GLP) inspection program. There was special focus on changes which might be made in the program to enhance the chances of detecting fraud in regulated studies. To this end, the Assistant Administrator of the Office of Prevention, Pesticides and Toxic Substances (OPPTS) requested EPA's Office of Inspector General (OIG) to examine the GLP program. Several reports were issued by the OIG, including the recommendation that a laboratory accreditation program be adopted. EPA has been examining ways to implement the OIG's recommendations, including (1) laboratory accreditation consisting of three components: document submission and assessment, site visit and assessment, and proficiency assessment; and (2) mandatory registration of all facilities participating in GLP-regulated studies, based on document submission and assessment. These two alternatives are compared, and the advantages and disadvantages of each are discussed.

  4. Physics and Accelerator Applications of RF Superconductivity

    SciTech Connect

    H. Padamsee; K. W. Shepard; Ron Sundelin

    1993-12-01

    A key component of any particle accelerator is the device that imparts energy gain to the charged particle. This is usually an electromagnetic cavity resonating at a microwave frequency, chosen between 100 and 3000 MHz. Serious attempts to utilize superconductors for accelerating cavities were initiated more than 25 years ago with the acceleration of electrons in a lead-plated resonator at Stanford University (1). The first full-scale accelerator, the Stanford SCA, was completed in 1978 at the High Energy Physics Laboratory (HEPL) (2). Over the intervening one and a half decades, superconducting cavities have become increasingly important to particle accelerators for nuclear physics and high energy physics. For continuous operation, as is required for many applications, the power dissipation in the walls of a copper structure is quite substantial, for example, 0.1 megawatts per meter of structure operating at an accelerating field of 1 million volts/meter (MV/m). since losses increase as the square of the accelerating field, copper cavities become severely uneconomical as demand for higher fields grows with the higher energies called for by experimenters to probe ever deeper into the structure of matter. Rf superconductivity has become an important technology for particle accelerators. Practical structures with attractive performance levels have been developed for a variety of applications, installed in the targeted accelerators, and operated over significant lengths of time. Substantial progress has been made in understanding field and Q limitations and in inventing cures to advance performance. The technical and economical potential of rf superconductivity makes it an important candidate for future advanced accelerators for free electron lasers, for nuclear physics, and for high energy physics, at the luminosity as well as at the energy frontiers.

  5. Accelerators for Inertial Fusion Energy Production

    NASA Astrophysics Data System (ADS)

    Bangerter, R. O.; Faltens, A.; Seidl, P. A.

    2014-02-01

    Since the 1970s, high energy heavy ion accelerators have been one of the leading options for imploding and igniting targets for inertial fusion energy production. Following the energy crisis of the early 1970s, a number of people in the international accelerator community enthusiastically began working on accelerators for this application. In the last decade, there has also been significant interest in using accelerators to study high energy density physics (HEDP). Nevertheless, research on heavy ion accelerators for fusion has proceeded slowly pending demonstration of target ignition using the National Ignition Facility (NIF), a laser-based facility at Lawrence Livermore National Laboratory. A recent report of the National Research Council recommends expansion of accelerator research in the US if and when the NIF achieves ignition. Fusion target physics and the economics of commercial energy production place constraints on the design of accelerators for fusion applications. From a scientific standpoint, phase space and space charge considerations lead to the most stringent constraints. Meeting these constraints almost certainly requires the use of multiple beams of heavy ions with kinetic energies > 1 GeV. These constraints also favor the use of singly charged ions. This article discusses the constraints for both fusion and HEDP, and explains how they lead to the requirements on beam parameters. RF and induction linacs are currently the leading contenders for fusion applications. We discuss the advantages and disadvantages of both options. We also discuss the principal issues that must yet be resolved.

  6. Cryogenic Technology for Superconducting Accelerators

    NASA Astrophysics Data System (ADS)

    Hosoyama, Kenji

    2012-01-01

    Superconducting devices such as magnets and cavities are key components in the accelerator field for increasing the beam energy and intensity, and at the same time making the system compact and saving on power consumption in operation. An effective cryogenic system is required to cool and keep the superconducting devices in the superconducting state stably and economically. The helium refrigeration system for application to accelerators will be discussed in this review article. The concept of two cooling modes -- the liquefier and refrigerator modes -- will be discussed in detail because of its importance for realizing efficient cooling and stable operation of the system. As an example of the practical cryogenic system, the TRISTAN cryogenic system of KEK Laboratory will be treated in detail and the main components of the cryogenic system, including the high-performance multichannel transfer line and liquid nitrogen circulation system at 80K, will also be discussed. In addition, we will discuss the operation of the cryogenic system, including the quench control and safety of the system. The satellite refrigeration system will be discussed because of its potential for wide application in medium-size accelerators and in industry.

  7. Compensation Techniques in Accelerator Physics

    SciTech Connect

    Sayed, Hisham Kamal

    2011-05-01

    Accelerator physics is one of the most diverse multidisciplinary fields of physics, wherein the dynamics of particle beams is studied. It takes more than the understanding of basic electromagnetic interactions to be able to predict the beam dynamics, and to be able to develop new techniques to produce, maintain, and deliver high quality beams for different applications. In this work, some basic theory regarding particle beam dynamics in accelerators will be presented. This basic theory, along with applying state of the art techniques in beam dynamics will be used in this dissertation to study and solve accelerator physics problems. Two problems involving compensation are studied in the context of the MEIC (Medium Energy Electron Ion Collider) project at Jefferson Laboratory. Several chromaticity (the energy dependence of the particle tune) compensation methods are evaluated numerically and deployed in a figure eight ring designed for the electrons in the collider. Furthermore, transverse coupling optics have been developed to compensate the coupling introduced by the spin rotators in the MEIC electron ring design.

  8. Self-accelerating warped braneworlds

    SciTech Connect

    Carena, Marcela; Lykken, Joseph; Santiago, Jose; Park, Minjoon

    2007-01-15

    Braneworld models with induced gravity have the potential to replace dark energy as the explanation for the current accelerating expansion of the Universe. The original model of Dvali, Gabadadze, and Porrati (DGP) demonstrated the existence of a 'self-accelerating' branch of background solutions, but suffered from the presence of ghosts. We present a new large class of braneworld models which generalize the DGP model. Our models have negative curvature in the bulk, allow a second brane, and have general brane tensions and localized curvature terms. We exhibit three different kinds of ghosts, associated to the graviton zero mode, the radion, and the longitudinal components of massive graviton modes. The latter two species occur in the DGP model, for negative and positive brane tension, respectively. In our models, we find that the two kinds of DGP ghosts are tightly correlated with each other, but are not always linked to the feature of self-acceleration. Our models are a promising laboratory for understanding the origins and physical meaning of braneworld ghosts, and perhaps for eliminating them altogether.

  9. Self-accelerating Warped Braneworlds

    SciTech Connect

    Carena, Marcela; Lykken, Joseph; Park, Minjoon; Santiago, Jose; /Fermilab

    2006-11-01

    Braneworld models with induced gravity have the potential to replace dark energy as the explanation for the current accelerating expansion of the Universe. The original model of Dvali, Gabadadze and Porrati (DGP) demonstrated the existence of a ''self-accelerating'' branch of background solutions, but suffered from the presence of ghosts. We present a new large class of braneworld models which generalize the DGP model. Our models have negative curvature in the bulk, allow a second brane, and have general brane tensions and localized curvature terms. We exhibit three different kinds of ghosts, associated to the graviton zero mode, the radion, and the longitudinal components of massive graviton modes. The latter two species occur in the DGP model, for negative and positive brane tension respectively. In our models, we find that the two kinds of DGP ghosts are tightly correlated with each other, but are not always linked to the feature of self-acceleration. Our models are a promising laboratory for understanding the origins and physical meaning of braneworld ghosts, and perhaps for eliminating them altogether.

  10. An introduction to acceleration mechanisms

    SciTech Connect

    Palmer, R.B.

    1987-05-01

    This paper discusses the acceleration of charged particles by electromagnetic fields, i.e., by fields that are produced by the motion of other charged particles driven by some power source. The mechanisms that are discussed include: Ponderamotive Forces, Acceleration, Plasma Beat Wave Acceleration, Inverse Free Electron Laser Acceleration, Inverse Cerenkov Acceleration, Gravity Acceleration, 2D Linac Acceleration and Conventional Iris Loaded Linac Structure Acceleration. (LSP)

  11. Debris and micrometeorite impact measurements in the laboratory

    NASA Technical Reports Server (NTRS)

    Resnick, J.; Grun, J.; Crawford, J.; Burris, R.; Manka, C. K.; Ford, J. L.; Ripin, B. H.

    1992-01-01

    A method was developed to simulate space debris in the laboratory. This method, which is an outgrowth of research in inertial confinement fusion (ICF), uses laser ablation to accelerate material. Using this method, single 60 micron aluminum spheres were accelerated to 15 km/sec and larger 500 micron aluminum spheres were accelerated to 2 km/sec. Also, many small (less than 10 micron diameter) irregularly shaped particles were accelerated to speeds of 100 km/sec.

  12. Accelerated cleanup risk reduction

    SciTech Connect

    Knapp, R.B.; Aines, R.M.; Blake, R.G.; Copeland, A.B.; Newmark, R.L.; Tompson, A.F.B.

    1998-02-01

    There is no proven technology for remediating contaminant plume source regions in a heterogeneous subsurface. This project is an interdisciplinary effort to develop the requisite new technologies so that will be rapidly accepted by the remediation community. Our technology focus is hydrous pyrolysis/oxidation (HPO) which is a novel in situ thermal technique. We have expanded this core technology to leverage the action of steam injection and place an in situ microbial filter downstream to intercept and destroy the accelerated movement of contaminated groundwater. Most contaminant plume source regions, including the chlorinated solvent plume at LLNL, are in subsurface media characterized by a wide range in hydraulic conductivity. At LLNL, the main conduits for contaminant transport are buried stream channels composed of gravels and sands; these have a hydraulic conductivity in the range of 10{sup -1} to 10{sup -2} cm/s. Clay and silt units with a hydraulic conductivity of 10{sup -1} to 10{sup -6} cm/s bound these buried channels; these are barriers to groundwater movement and contain the highest contaminant concentrations in the source region. New remediation technologies are required because the current ones preferentially access the high conductivity units. HPO is an innovative process for the in situ destruction of contaminants in the entire subsurface. It operates by the injection of steam. We have demonstrated in laboratory experiments that many contaminants rapidly oxidize to harmless compounds at temperatures easily achieved by injecting steam, provided sufficient dissolved oxygen is present. One important challenge in a heterogeneous source region is getting heat, contaminants, and an oxidizing agent in the same place at the same time. We have used the NUFT computer program to simulate the cyclic injection of steam into a contaminated aquifer for design of a field demonstration. We used an 8 hour, steam/oxygen injection cycle followed by a 56 hour relaxation

  13. Schooling in Times of Acceleration

    ERIC Educational Resources Information Center

    Buddeberg, Magdalena; Hornberg, Sabine

    2017-01-01

    Modern societies are characterised by forms of acceleration, which influence social processes. Sociologist Hartmut Rosa has systematised temporal structures by focusing on three categories of social acceleration: technical acceleration, acceleration of social change, and acceleration of the pace of life. All three processes of acceleration are…

  14. Operation of the accelerator

    SciTech Connect

    Pardo, R.C.; Batzka, B.; Billquist, P.J.

    1995-08-01

    Fiscal Year 1994 was the first year of seven-day operation since ATLAS became a national user facility in 1985. ATLAS made the most of the opportunity this year by providing 5200 hours of beam on-target to the research program. A record number of 60 experiments were completed and the {open_quotes}facility reliability{close_quotes} remained near the 90% level. Seven-day operation was made possible with the addition to the staff of two operator positions providing single-operator coverage during the weekend period. The normally scheduled coverage was augmented by an on-call list of system experts who respond to emergencies with phone-in advice and return to the Laboratory when necessary. This staffing approach continues but we rearranged our staffing patterns so that we now have one cryogenics engineer working a shift pattern which includes 8-hour daily coverage during the weekend. ATLAS provided a beam mix to users consisting of 26 different isotopic species, 23% of which were for A>100 in FY 1994. Approximately 60% of the beam time was provided by the Positive Ion Injector, slightly less than the usage rate of FY 1993. Experiments using uranium or lead beams accounted for 16.4% of the total beam time. The ECR ion source and high-voltage platform functioned well throughout the year. A new technique for solid material production in the source was developed which uses a sputtering process wherein the sample of material placed near the plasma chamber wall is biased negatively. Plasma ions are accelerated into the sample and material is sputtered from the surface into the plasma. This technique is now used routinely for many elements. Runs of calcium, germanium, nickel, lead, tellurium, and uranium were carried out with this technique.

  15. Uniformly accelerated black holes

    NASA Astrophysics Data System (ADS)

    Letelier, Patricio S.; Oliveira, Samuel R.

    2001-09-01

    The static and stationary C metric are examined in a generic framework and their interpretations studied in some detail, especially those with two event horizons, one for the black hole and another for the acceleration. We find that (i) the spacetime of an accelerated static black hole is plagued by either conical singularities or a lack of smoothness and compactness of the black hole horizon, (ii) by using standard black hole thermodynamics we show that accelerated black holes have a higher Hawking temperature than Unruh temperature of the accelerated frame, and (iii) the usual upper bound on the product of the mass and acceleration parameters (<1/27) is just a coordinate artifact. The main results are extended to accelerated rotating black holes with no significant changes.

  16. The Dielectric Wall Accelerator

    SciTech Connect

    Caporaso, George J.; Chen, Yu-Jiuan; Sampayan, Stephen E.

    2009-01-01

    The Dielectric Wall Accelerator (DWA), a class of induction accelerators, employs a novel insulating beam tube to impress a longitudinal electric field on a bunch of charged particles. The surface flashover characteristics of this tube may permit the attainment of accelerating gradients on the order of 100 MV/m for accelerating pulses on the order of a nanosecond in duration. A virtual traveling wave of excitation along the tube is produced at any desired speed by controlling the timing of pulse generating modules that supply a tangential electric field to the tube wall. Because of the ability to control the speed of this virtual wave, the accelerator is capable of handling any charge to mass ratio particle; hence it can be used for electrons, protons and any ion. The accelerator architectures, key technologies and development challenges will be described.

  17. Airborne active and passive L-band measurements using PALS instrument in SMAPVEX12 soil moisture field campaign

    NASA Astrophysics Data System (ADS)

    Colliander, Andreas; Yueh, Simon; Chazanoff, Seth; Dinardo, Steven; O'Dwyer, Ian; Jackson, Thomas; McNairn, Heather; Bullock, Paul; Wiseman, Grant; Berg, Aaron; Magagi, Ramata; Njoku, Eni

    2012-10-01

    NASA's (National Aeronautics and Space Administration) Soil Moisture Active Passive (SMAP) Mission is scheduled for launch in late 2014. The objective of the mission is global mapping of soil moisture and freeze/thaw state. Merging of active and passive L-band observations of the mission will enable unprecedented combination of accuracy, resolution, coverage and revisit-time for soil moisture and freeze/thaw state retrieval. For pre-launch algorithm development and validation the SMAP project and NASA coordinated a field campaign named as SMAPVEX12 (Soil Moisture Active Passive Validation Experiment 2012) together with Agriculture and Agri-Food Canada, and other Canadian and US institutions in the vicinity of Winnipeg, Canada in June-July, 2012. The main objective of SMAPVEX12 was acquisition of a data record that features long time-series with varying soil moisture and vegetation conditions over an aerial domain of multiple parallel flight lines. The coincident active and passive L-band data was acquired with the PALS (Passive Active L-band System) instrument. The measurements were conducted over the experiment domain every 2-3 days on average, over a period of 43 days. The preliminary calibration of the brightness temperatures obtained in the campaign has been performed. Daily lake calibrations were used to adjust the radiometer calibration parameters, and the obtained measurements were compared against the raw in situ soil moisture measurements. The evaluation shows that this preliminary calibration of the data produces already a consistent brightness temperature record over the campaign duration, and only secondary adjustments and cleaning of the data is need before the data can be applied to the development and validation of SMAP algorithms.

  18. Optically pulsed electron accelerator

    DOEpatents

    Fraser, J.S.; Sheffield, R.L.

    1985-05-20

    An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radiofrequency-powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

  19. Optically pulsed electron accelerator

    DOEpatents

    Fraser, John S.; Sheffield, Richard L.

    1987-01-01

    An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radio frequency powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

  20. ACCELERATION RESPONSIVE SWITCH

    DOEpatents

    Chabrek, A.F.; Maxwell, R.L.

    1963-07-01

    An acceleration-responsive device with dual channel capabilities whereby a first circuit is actuated upon attainment of a predetermined maximum acceleration level and when the acceleration drops to a predetermined minimum acceleriltion level another circuit is actuated is described. A fluid-damped sensing mass slidably mounted in a relatively frictionless manner on a shaft through the intermediation of a ball bushing and biased by an adjustable compression spring provides inertially operated means for actuating the circuits. (AEC)

  1. The foxhole accelerating structure

    SciTech Connect

    Fernow, R.C.; Claus, J.

    1992-07-17

    This report examines some properties of a new type of open accelerating structure. It consists of a series of rectangular cavities, which we call foxholes, joined by a beam channel. The power for accelerating the particles comes from an external radiation source and enters the cavities through their open upper surfaces. Analytic and computer calculations are presented showing that the foxhole is a suitable structure for accelerating relativistic electrons.

  2. Particle acceleration in flares

    NASA Technical Reports Server (NTRS)

    Benz, Arnold O.; Kosugi, Takeo; Aschwanden, Markus J.; Benka, Steve G.; Chupp, Edward L.; Enome, Shinzo; Garcia, Howard; Holman, Gordon D.; Kurt, Victoria G.; Sakao, Taro

    1994-01-01

    Particle acceleration is intrinsic to the primary energy release in the impulsive phase of solar flares, and we cannot understand flares without understanding acceleration. New observations in soft and hard X-rays, gamma-rays and coherent radio emissions are presented, suggesting flare fragmentation in time and space. X-ray and radio measurements exhibit at least five different time scales in flares. In addition, some new observations of delayed acceleration signatures are also presented. The theory of acceleration by parallel electric fields is used to model the spectral shape and evolution of hard X-rays. The possibility of the appearance of double layers is further investigated.

  3. Charged particle accelerator grating

    DOEpatents

    Palmer, Robert B.

    1986-01-01

    A readily disposable and replaceable accelerator grating for a relativistic particle accelerator. The grating is formed for a plurality of liquid droplets that are directed in precisely positioned jet streams to periodically dispose rows of droplets along the borders of a predetermined particle beam path. A plurality of lasers are used to direct laser beams into the droplets, at predetermined angles, thereby to excite the droplets to support electromagnetic accelerating resonances on their surfaces. Those resonances operate to accelerate and focus particles moving along the beam path. As the droplets are distorted or destroyed by the incoming radiation, they are replaced at a predetermined frequency by other droplets supplied through the jet streams.

  4. Charged particle accelerator grating

    DOEpatents

    Palmer, Robert B.

    1986-09-02

    A readily disposable and replaceable accelerator grating for a relativistic particle accelerator. The grating is formed for a plurality of liquid droplets that are directed in precisely positioned jet streams to periodically dispose rows of droplets along the borders of a predetermined particle beam path. A plurality of lasers are used to direct laser beams into the droplets, at predetermined angles, thereby to excite the droplets to support electromagnetic accelerating resonances on their surfaces. Those resonances operate to accelerate and focus particles moving along the beam path. As the droplets are distorted or destroyed by the incoming radiation, they are replaced at a predetermined frequency by other droplets supplied through the jet streams.

  5. Accelerator-based BNCT.

    PubMed

    Kreiner, A J; Baldo, M; Bergueiro, J R; Cartelli, D; Castell, W; Thatar Vento, V; Gomez Asoia, J; Mercuri, D; Padulo, J; Suarez Sandin, J C; Erhardt, J; Kesque, J M; Valda, A A; Debray, M E; Somacal, H R; Igarzabal, M; Minsky, D M; Herrera, M S; Capoulat, M E; Gonzalez, S J; del Grosso, M F; Gagetti, L; Suarez Anzorena, M; Gun, M; Carranza, O

    2014-06-01

    The activity in accelerator development for accelerator-based BNCT (AB-BNCT) both worldwide and in Argentina is described. Projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators are briefly presented. In particular, the present status and recent progress of the Argentine project will be reviewed. The topics will cover: intense ion sources, accelerator tubes, transport of intense beams, beam diagnostics, the (9)Be(d,n) reaction as a possible neutron source, Beam Shaping Assemblies (BSA), a treatment room, and treatment planning in realistic cases.

  6. FFAGS for rapid acceleration

    SciTech Connect

    Carol J. Johnstone and Shane Koscielniak

    2002-09-30

    When large transverse and longitudinal emittances are to be transported through a circular machine, extremely rapid acceleration holds the advantage that the beam becomes immune to nonlinear resonances because there is insufficient time for amplitudes to build up. Uncooled muon beams exhibit large emittances and require fast acceleration to avoid decay losses and would benefit from this style of acceleration. The approach here employs a fixed-field alternating gradient or FFAG magnet structure and a fixed frequency acceleration system. Acceptance is enhanced by the use only of linear lattice elements, and fixed-frequency rf enables the use of cavities with large shunt resistance and quality factor.

  7. Acceleration of polarized protons in circular accelerators

    SciTech Connect

    Courant, E.D.; Ruth, R.D.

    1980-09-12

    The theory of depolarization in circular accelerators is presented. The spin equation is first expressed in terms of the particle orbit and then converted to the equivalent spinor equation. The spinor equation is then solved for three different situations: (1) a beam on a flat top near a resonance, (2) uniform acceleration through an isolated resonance, and (3) a model of a fast resonance jump. Finally, the depolarization coefficient, epsilon, is calculated in terms of properties of the particle orbit and the results are applied to a calculation of depolarization in the AGS.

  8. Pulsed power for particle beam accelerators in military applications

    SciTech Connect

    Smith, I.D.

    1980-06-20

    Techniques useful for generating and conditioning power for high energy pulsed accelerators with potential weapon applications are described. Pulsed electron accelerators are exemplified by ETA and ATA at Lawrence Livermore Laboratories and RADLAC at Sandia Laboratories Albuquerque. Pulse-power techniques used in other applications are briefly mentioned, including some that may be useful for collective ion accelerators. The limitations of pulse-power and the general directions of desirable development are illustrated. The main needs are to increase repetition rate and to decrease size.

  9. Status of the Wisconsin Plasma Astrophysics Laboratory

    NASA Astrophysics Data System (ADS)

    Wallace, John; Clark, Mike; Endrizzi, Doug; Flanagan, Ken; Milhone, Jason; Peterson, Ethan; Olson, Joseph; Stemo, Aaron; Weisberg, Dave; Egedal, Jan; Forest, Cary

    2015-11-01

    The Wisconsin Plasma Astrophysics Laboratory (WiPAL) is a facility that now encompasses a collection of novel plasma astrophysics experimental configurations. In the MPDX configuration large, un-magnetized, fast flowing, hot plasma is being used to investigate a variety of flow driven MHD instabilities. The experiment is 3 meters in diameter and utilizes a permanent magnet multicusp plasma confinement. Five 20KW, 2.45 GHz, CW magnetrons produce electron cyclotron heating for plasma generation. Ten lanthanum hexaboride (LaB6) stirring rods and molybdenum anodes are inserted into the vessel to produce JxB flows. The chamber has a variety of multiuse ports, and is able to split open to allow experimental apparatus to be inserted. This poster will describe recent improvements to the laboratory. We will also provide an overview of existing and future experimental configurations including: reconnection (TREX); acoustic and Alfven wave propagation in connection with helioseismology; pulsar and stellar wind launching from a rotating dipolar magnetosphere; jet formation and propagation into background plasma; and small-scale, high power helicity injection. Construction was funded by the NSF Major Research Instrumentation program (ARRA), DOE, and CMSO.

  10. Laboratory directed research and development

    SciTech Connect

    Not Available

    1991-11-15

    The purposes of Argonne's Laboratory Directed Research and Development (LDRD) Program are to encourage the development of novel concepts, enhance the Laboratory's R D capabilities, and further the development of its strategic initiatives. Among the aims of the projects supported by the Program are establishment of engineering proof-of-principle''; development of an instrumental prototype, method, or system; or discovery in fundamental science. Several of these project are closely associated with major strategic thrusts of the Laboratory as described in Argonne's Five Year Institutional Plan, although the scientific implications of the achieved results extend well beyond Laboratory plans and objectives. The projects supported by the Program are distributed across the major programmatic areas at Argonne. Areas of emphasis are (1) advanced accelerator and detector technology, (2) x-ray techniques in biological and physical sciences, (3) advanced reactor technology, (4) materials science, computational science, biological sciences and environmental sciences. Individual reports summarizing the purpose, approach, and results of projects are presented.

  11. The Naples University 3 MV tandem accelerator

    SciTech Connect

    Campajola, L.; Brondi, A.

    2013-07-18

    The 3 MV tandem accelerator of the Naples University is used for research activities and applications in many fields. At the beginning of operation (1977) the main utilization was in the field of nuclear physics. Later, the realization of new beam lines allowed the development of applied activities as radiocarbon dating, ion beam analysis, biophysics, ion implantation etc. At present, the availability of different ion sources and many improvements on the accelerator allow to run experiments in a wide range of subjects. An overview of the characteristics and major activities of the laboratory is presented.

  12. Technology development for high power induction accelerators

    SciTech Connect

    Birx, D.L.; Reginato, L.L.

    1985-06-11

    The marriage of Induction Linac technology with Nonlinear Magnetic Modulators has produced some unique capabilities. It appears possible to produce electron beams with average currents measured in amperes, at gradients exceeding 1 MeV/meter, and with power efficiencies approaching 50%. A 2 MeV, 5 kA electron accelerator has been constructed at the Lawrence Livermore National Laboratory (LLNL) to demonstrate these concepts and to provide a test facility for high brightness sources. The pulse drive for the accelerator is based on state-of-the-art magnetic pulse compressors with very high peak power capability, repetition rates exceeding a kilohertz and excellent reliability.

  13. COMPACT ACCELERATOR CONCEPT FOR PROTON THERAPY

    SciTech Connect

    Caporaso, G; Sampayan, S; Chen, Y; Harris, J; Hawkins, S; Holmes, C; Krogh, M; Nelson, S; Nunnally, W; Paul, A; Poole, B; Rhodes, M; Sanders, D; Selenes, K; Sullivan, J; Wang, L; Watson, J

    2006-08-18

    A new type of compact induction accelerator is under development at the Lawrence Livermore National Laboratory that promises to increase the average accelerating gradient by at least an order of magnitude over that of existing induction machines. The machine is based on the use of high gradient vacuum insulators, advanced dielectric materials and switches and is being developed as a compact flash x-ray radiography source. Research describing an extreme variant of this technology aimed at proton therapy for cancer will be presented.

  14. Laboratory diagnosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the first major goals of the microbiology laboratory is to isolate or detect clinically significant microorganisms from an affected site and, if more than one type of microorganism is present, to isolate them in approximately the same ratio as occurs in vivo. Whether an isolate is “clinically...

  15. Scaling FFAG accelerator for muon acceleration

    SciTech Connect

    Lagrange, JB.; Planche, T.; Mori, Y.

    2011-10-06

    Recent developments in scaling fixed field alternating gradient (FFAG) accelerators have opened new ways for lattice design, with straight sections, and insertions like dispersion suppressors. Such principles and matching issues are detailed in this paper. An application of these new concepts is presented to overcome problems in the PRISM project.

  16. Scaling FFAG accelerator for muon acceleration

    NASA Astrophysics Data System (ADS)

    Lagrange, JB.; Planche, T.; Mori, Y.

    2011-10-01

    Recent developments in scaling fixed field alternating gradient (FFAG) accelerators have opened new ways for lattice design, with straight sections, and insertions like dispersion suppressors. Such principles and matching issues are detailed in this paper. An application of these new concepts is presented to overcome problems in the PRISM project.

  17. Angular velocities, angular accelerations, and coriolis accelerations

    NASA Technical Reports Server (NTRS)

    Graybiel, A.

    1975-01-01

    Weightlessness, rotating environment, and mathematical analysis of Coriolis acceleration is described for man's biological effective force environments. Effects on the vestibular system are summarized, including the end organs, functional neurology, and input-output relations. Ground-based studies in preparation for space missions are examined, including functional tests, provocative tests, adaptive capacity tests, simulation studies, and antimotion sickness.

  18. Chemical Synthesis Accelerated by Paper Spray: The Haloform Reaction

    ERIC Educational Resources Information Center

    Bain, Ryan M.; Pulliam, Christopher J.; Raab, Shannon A.; Cooks, R. Graham

    2016-01-01

    In this laboratory, students perform a synthetic reaction in two ways: (i) by traditional bulk-phase reaction and (ii) in the course of reactive paper spray ionization. Mass spectrometry (MS) is used both as an analytical method and a means of accelerating organic syntheses. The main focus of this laboratory exercise is that the same ionization…

  19. Improvement of Space Shuttle Main Engine Low Frequency Acceleration Measurements

    NASA Technical Reports Server (NTRS)

    Stec, Robert C.

    1999-01-01

    The noise floor of low frequency acceleration data acquired on the Space Shuttle Main Engines is higher than desirable. Difficulties of acquiring high quality acceleration data on this engine are discussed. The approach presented in this paper for reducing the acceleration noise floor focuses on a search for an accelerometer more capable of measuring low frequency accelerations. An overview is given of the current measurement system used to acquire engine vibratory data. The severity of vibration, temperature, and moisture environments are considered. Vibratory measurements from both laboratory and rocket engine tests are presented.

  20. Vacuum Insulator Development for the Dielectric Wall Accelerator

    SciTech Connect

    Harris, J R; Blackfield, D; Caporaso, G J; Chen, Y; Hawkins, S; Kendig, M; Poole, B; Sanders, D M; Krogh, M; Managan, J E

    2008-03-17

    At Lawrence Livermore National Laboratory, we are developing a new type of accelerator, known as a Dielectric Wall Accelerator, in which compact pulse forming lines directly apply an accelerating field to the beam through an insulating vacuum boundary. The electrical strength of this insulator may define the maximum gradient achievable in these machines. To increase the system gradient, we are using 'High Gradient Insulators' composed of alternating layers of dielectric and metal for the vacuum insulator. In this paper, we present our recent results from experiment and simulation, including the first test of a High Gradient Insulator in a functioning Dielectric Wall Accelerator cell.

  1. Induction linear accelerators

    NASA Astrophysics Data System (ADS)

    Birx, Daniel

    1992-03-01

    Among the family of particle accelerators, the Induction Linear Accelerator is the best suited for the acceleration of high current electron beams. Because the electromagnetic radiation used to accelerate the electron beam is not stored in the cavities but is supplied by transmission lines during the beam pulse it is possible to utilize very low Q (typically<10) structures and very large beam pipes. This combination increases the beam breakup limited maximum currents to of order kiloamperes. The micropulse lengths of these machines are measured in 10's of nanoseconds and duty factors as high as 10-4 have been achieved. Until recently the major problem with these machines has been associated with the pulse power drive. Beam currents of kiloamperes and accelerating potentials of megavolts require peak power drives of gigawatts since no energy is stored in the structure. The marriage of liner accelerator technology and nonlinear magnetic compressors has produced some unique capabilities. It now appears possible to produce electron beams with average currents measured in amperes, peak currents in kiloamperes and gradients exceeding 1 MeV/meter, with power efficiencies approaching 50%. The nonlinear magnetic compression technology has replaced the spark gap drivers used on earlier accelerators with state-of-the-art all-solid-state SCR commutated compression chains. The reliability of these machines is now approaching 1010 shot MTBF. In the following paper we will briefly review the historical development of induction linear accelerators and then discuss the design considerations.

  2. Accelerator Science: Why RF?

    SciTech Connect

    Lincoln, Don

    2016-12-21

    Particle accelerators can fire beams of subatomic particles at near the speed of light. The accelerating force is generated using radio frequency technology and a whole lot of interesting features. In this video, Fermilab’s Dr. Don Lincoln explains how it all works.

  3. Particle Acceleration in Jets

    NASA Technical Reports Server (NTRS)

    Nishikawa, Ken-Ichi

    2005-01-01

    Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks, e.g., active galactic nuclei (AGNs), gamma ray burst (GRBs), and Galactic microquasar systems usually have power-law emission spectra. Fermi acceleration is the mechanism usually assumed for the acceleration of particles in astrophysical environments.

  4. Accelerators Beyond The Tevatron?

    SciTech Connect

    Lach, Joseph; /Fermilab

    2010-07-01

    Following the successful operation of the Fermilab superconducting accelerator three new higher energy accelerators were planned. They were the UNK in the Soviet Union, the LHC in Europe, and the SSC in the United States. All were expected to start producing physics about 1995. They did not. Why?

  5. Accelerators (3/5)

    ScienceCinema

    None

    2016-07-12

    1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges Prerequisite knowledge: Previous knowledge of accelerators is not required.

  6. Accelerators (4/5)

    ScienceCinema

    None

    2016-07-12

    1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges Prerequisite knowledge: Previous knowledge of accelerators is not required.

  7. Measuring Model Rocket Acceleration.

    ERIC Educational Resources Information Center

    Jenkins, Randy A.

    1993-01-01

    Presents an experiment that measures the acceleration and velocity of a model rocket. Lift-off information is transmitted to a computer that creates a graph of the velocity. Discusses the analysis of the computer-generated data and differences between calculated and experimental velocity and acceleration of several rocket types. (MDH)

  8. Microscale acceleration history discriminators

    DOEpatents

    Polosky, Marc A.; Plummer, David W.

    2002-01-01

    A new class of micromechanical acceleration history discriminators is claimed. These discriminators allow the precise differentiation of a wide range of acceleration-time histories, thereby allowing adaptive events to be triggered in response to the severity (or lack thereof) of an external environment. Such devices have applications in airbag activation, and other safety and surety applications.

  9. Accelerators (5/5)

    ScienceCinema

    None

    2016-07-12

    1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges Prerequisite knowledge: Previous knowledge of accelerators is not required.

  10. Accelerators Beyond The Tevatron?

    SciTech Connect

    Lach, Joseph

    2010-07-29

    Following the successful operation of the Fermilab superconducting accelerator three new higher energy accelerators were planned. They were the UNK in the Soviet Union, the LHC in Europe, and the SSC in the United States. All were expected to start producing physics about 1995. They did not. Why?.

  11. ACCELERATED SOLVENT EXTRACTION COMBINED WITH ...

    EPA Pesticide Factsheets

    A research project was initiated to address a recurring problem of elevated detection limits above required risk-based concentrations for the determination of semivolatile organic compounds in high moisture content solid samples. This project was initiated, in cooperation with the EPA Region 1 Laboratory, under the Regional Methods Program administered through the ORD Office of Science Policy. The aim of the project was to develop an approach for the rapid removal of water in high moisture content solids (e.g., wetland sediments) in preparation for analysis via Method 8270. Alternative methods for water removal have been investigated to enhance compound solid concentrations and improve extraction efficiency, with the use of pressure filtration providing a high-throughput alternative for removal of the majority of free water in sediments and sludges. In order to eliminate problems with phase separation during extraction of solids using Accelerated Solvent Extraction, a variation of a water-isopropanol extraction method developed at the USGS National Water Quality Laboratory in Denver, CO is being employed. The concentrations of target compounds in water-isopropanol extraction fluids are subsequently analyzed using an automated Solid Phase Extraction (SPE)-GC/MS method developed in our laboratory. The coupled approaches for dewatering, extraction, and target compound identification-quantitation provide a useful alternative to enhance sample throughput for Me

  12. A worldly approach to a new accelerator

    SciTech Connect

    Taubes, G.

    1993-02-19

    Particle physicists are learning to their discomfiture that for one country to plan a multibillion-dollar accelerator, then ask other countries to help build it, is a recipe for frustration. That's the lesson emerging from the struggles to build the Superconducting Super Collider (SSC), the mammoth accelerator that is now in limbo as officials wait to see whether Japan and other nations will pitch in. But a group of laboratory directors who are already planning the next-generation accelerator - a large linear collider that will address physics the SSC can't probe - is taking steps to ensure that it will be an international collaboration from day one. The machine would be a linear accelerator tens of kilometers long with an energy limit of 1 TeV, and would collide electrons and positrons. Two international collaborations are studying designs for radiofreqency cavities that would generate powerful accelerating gradients. A third international group is working on learning how to focus electron and positron beams down to 60 nm in diameter. The proposed accelerator would likely cost $2 to $3 billion, and one possible location is the big island of Hawaii.

  13. Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams

    SciTech Connect

    Siemann, R.H.; /SLAC

    2011-10-24

    Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.

  14. The Lawrence Livermore National Laboratory (LLNL) multi-user Tandem Laboratory

    SciTech Connect

    Davis, J.C.

    1988-09-01

    An FN tandem laboratory, cofounded by several Lawrence Livermore National Laboratory Divisions, Sandia Livermore, and the University of California Regents, is now operational at Livermore. The accelerator, formerly the University of Washington injector, has been upgraded with SF/sub 6/, Dowlish tubes, and a NEC pelletron charging system. A conventional duoplasmatron, a tritium source, and two Cs sputtering sources will be fielded on the accelerator. Pulsed beams will be available from two source positions. The laboratory has been designed to accommodate up to 19 experimental positions with excellent optics and working vacuum. The facility is unshielded with both accelerator and radiological systems under the control of a distributed microprocessor system. Research activities at the tandem include nuclear physics and astrophysics, materials science and characterization programs, and accelerator mass spectrometry for archaeology, biomedical, environmental and geoscience investigators. 3 refs., 1 fig.

  15. Teaching and Research with Accelerators at Tarleton State University

    SciTech Connect

    Marble, Daniel K.

    2009-03-10

    Tarleton State University students began performing both research and laboratory experiments using accelerators in 1998 through visitation programs at the University of North Texas, US Army Research Laboratory, and the Naval Surface Warfare Center at Carderock. In 2003, Tarleton outfitted its new science building with a 1 MV pelletron that was donated by the California Institution of Technology. The accelerator has been upgraded and supports a wide range of classes for both the Physics program and the ABET accredited Engineering Physics program as well as supplying undergraduate research opportunities on campus. A discussion of various laboratory activities and research projects performed by Tarleton students will be presented.

  16. 15 Years of R&D on high field accelerator magnets at FNAL

    DOE PAGES

    Barzi, Emanuela; Zlobin, Alexander V.

    2016-07-01

    The High Field Magnet (HFM) Program at Fermi National Accelerator Laboratory (FNAL) has been developing Nb3Sn superconducting magnets, materials and technologies for present and future particle accelerators since the late 1990s. This paper summarizes the main results of the Nb3Sn accelerator magnet and superconductor R&D at FNAL and outlines the Program next steps.

  17. Lunar laboratory

    SciTech Connect

    Keaton, P.W.; Duke, M.B.

    1986-01-01

    An international research laboratory can be established on the Moon in the early years of the 21st Century. It can be built using the transportation system now envisioned by NASA, which includes a space station for Earth orbital logistics and orbital transfer vehicles for Earth-Moon transportation. A scientific laboratory on the Moon would permit extended surface and subsurface geological exploration; long-duration experiments defining the lunar environment and its modification by surface activity; new classes of observations in astronomy; space plasma and fundamental physics experiments; and lunar resource development. The discovery of a lunar source for propellants may reduce the cost of constructing large permanent facilities in space and enhance other space programs such as Mars exploration. 29 refs.

  18. PALS (Passive Active L-band System) Radiometer-Based Soil Moisture Retrieval for the SMAP Validation Experiment 2012 (SMAPVEX12)

    NASA Astrophysics Data System (ADS)

    Colliander, A.; Jackson, T. J.; Chan, S.; Bindlish, R.; O'Neill, P. E.; Chazanoff, S. L.; McNairn, H.; Bullock, P.; Powers, J.; Wiseman, G.; Berg, A. A.; Magagi, R.; Njoku, E. G.

    2014-12-01

    NASA's (National Aeronautics and Space Administration) Soil Moisture Active Passive (SMAP) mission is scheduled for launch in early January 2015. For pre-launch soil moisture algorithm development and validation, the SMAP project and NASA coordinated a SMAP Validation Experiment 2012 (SMAPVEX12) together with Agriculture and Agri-Food Canada in the vicinity of Winnipeg, Canada in June 7-July 19, 2012. Coincident active and passive airborne L-band data were acquired using the Passive Active L-band System (PALS) on 17 days during the experiment. Simultaneously with the PALS measurements, soil moisture ground truth data were collected manually. The vegetation and surface roughness were sampled on non-flight days. The SMAP mission will produce surface (top 5 cm) soil moisture products a) using a combination of its L-band radiometer and SAR (Synthetic Aperture Radar) measurements, b) using the radiometer measurement only, and c) using the SAR measurements only. The SMAPVEX12 data are being utilized for the development and testing of the algorithms applied for generating these soil moisture products. This talk will focus on presenting results of retrieving surface soil moisture using the PALS radiometer. The issues that this retrieval faces are very similar to those faced by the global algorithm using the SMAP radiometer. However, the different spatial resolution of the two observations has to be accounted for in the analysis. The PALS 3 dB footprint in the experiment was on the order of 1 km, whereas the SMAP radiometer has a footprint of about 40 km. In this talk forward modeled brightness temperature over the manually sampled fields and the retrieved soil moisture over the entire experiment domain are presented and discussed. In order to provide a retrieval product similar to that of the SMAP passive algorithm, various ancillary information had to be obtained for the SMAPVEX12 domain. In many cases there are multiple options on how to choose and reprocess these data

  19. Laboratory accreditation

    SciTech Connect

    Pettit, R.B.

    1998-08-01

    Accreditation can offer many benefits to a testing or calibration laboratory, including increased marketability of services, reduced number of outside assessments, and improved quality of services. Compared to ISO 9000 registration, the accreditation process includes a review of the entire quality system, but in addition a review of testing or calibration procedures by a technical expert and participation in proficiency testing in the areas of accreditation. Within the DOE, several facilities have recently become accredited in the area of calibration, including Sandia National Laboratories, Oak Ridge, AlliedSignal FM and T; Lockheed Martin Idaho Technologies Co., and Pacific Northwest National Lab. At the national level, a new non-profit organization was recently formed called the National Cooperation for Laboratory Accreditation (NACLA). The goal of NACLA is to develop procedures, following national and international requirements, for the recognition of competent accreditation bodies in the US. NACLA is a voluntary partnership between the public and private sectors with the goal of a test or calibration performed once and accepted world wide. The NACLA accreditation body recognition process is based on the requirements of ISO Guide 25 and Guide 58. A membership drive will begin some time this fall to solicit organizational members and an election of a permanent NACLA Board of Directors will follow later this year or early 1999.

  20. Cloning and construction of recombinant palI gene from Klebsiella oxytoca on pET-32b into E. coli BL21 (DE3) pLysS for production of isomaltulose, a new generation of sugar

    SciTech Connect

    Moeis, Maelita R. Berlian, Liska Suhandono, Sony Prima, Alex Komalawati, Eli Kristianti, Tati

    2014-03-24

    Klebsiella oxytoca produces sucrose isomerase which catalyses the conversion of sucrose to isomaltulose, a new generation of sugar. From the previous study, palI gene from Klebsiella oxytoca was succesfully isolated from sapodilla fruit (Manilkara zapota). The full-length palI gene sequence of Klebsiella oxytoca was cloned in E. coli DH5α. The deduced amino acid sequence shows 498 residues which includes conserved motif for sucrose isomerisation {sup 325}RLDRD{sup 329} and 97% identical to palI gene from Klebsiella sp. LX3 (GenBank:AAK82938.1). This fragment was succesfullly ligated into the expression vector pET-32b using overlap-extension PCR and cloned in Escherichia coli BL21 (DE3) pLysS. DNA sequencing result shows that palI gene of Klebsiella oxytoca was inserted in-frame in pET-32b. This is the first report on cloning of palI gene from Klebsiella oxytoca.

  1. Cloning and construction of recombinant palI gene from Klebsiella oxytoca on pET-32b into E. coli BL21 (DE3) pLysS for production of isomaltulose, a new generation of sugar

    NASA Astrophysics Data System (ADS)

    Moeis, Maelita R.; Berlian, Liska; Suhandono, Sony; Prima, Alex; Komalawati, Eli; Kristianti, Tati

    2014-03-01

    Klebsiella oxytoca produces sucrose isomerase which catalyses the conversion of sucrose to isomaltulose, a new generation of sugar. From the previous study, palI gene from Klebsiella oxytoca was succesfully isolated from sapodilla fruit (Manilkara zapota). The full-length palI gene sequence of Klebsiella oxytoca was cloned in E. coli DH5α. The deduced amino acid sequence shows 498 residues which includes conserved motif for sucrose isomerisation 325RLDRD329 and 97% identical to palI gene from Klebsiella sp. LX3 (GenBank:AAK82938.1). This fragment was succesfullly ligated into the expression vector pET-32b using overlap-extension PCR and cloned in Escherichia coli BL21 (DE3) pLysS. DNA sequencing result shows that palI gene of Klebsiella oxytoca was inserted in-frame in pET-32b. This is the first report on cloning of palI gene from Klebsiella oxytoca.

  2. Large electrostatic accelerators

    SciTech Connect

    Jones, C.M.

    1984-01-01

    The increasing importance of energetic heavy ion beams in the study of atomic physics, nuclear physics, and materials science has partially or wholly motivated the construction of a new generation of large electrostatic accelerators designed to operate at terminal potentials of 20 MV or above. In this paper, the author briefly discusses the status of these new accelerators and also discusses several recent technological advances which may be expected to further improve their performance. The paper is divided into four parts: (1) a discussion of the motivation for the construction of large electrostatic accelerators, (2) a description and discussion of several large electrostatic accelerators which have been recently completed or are under construction, (3) a description of several recent innovations which may be expected to improve the performance of large electrostatic accelerators in the future, and (4) a description of an innovative new large electrostatic accelerator whose construction is scheduled to begin next year. Due to time and space constraints, discussion is restricted to consideration of only tandem accelerators.

  3. Centrifuge Study of Pilot Tolerance to Acceleration and the Effects of Acceleration on Pilot Performance

    NASA Technical Reports Server (NTRS)

    Creer, Brent Y.; Smedal, Harald A.; Wingrove, Rodney C.

    1960-01-01

    A research program the general objective of which was to measure the effects of various sustained accelerations on the control performance of pilots, was carried out on the Aviation Medical Acceleration Laboratory centrifuge, U.S. Naval Air Development Center, Johnsville, PA. The experimental setup consisted of a flight simulator with the centrifuge in the control loop. The pilot performed his control tasks while being subjected to acceleration fields such as might be encountered by a forward-facing pilot flying an atmosphere entry vehicle. The study was divided into three phases. In one phase of the program, the pilots were subjected to a variety of sustained linear acceleration forces while controlling vehicles with several different sets of longitudinal dynamics. Here, a randomly moving target was displayed to the pilot on a cathode-ray tube. For each combination of acceleration field and vehicle dynamics, pilot tracking accuracy was measured and pilot opinion of the stability and control characteristics was recorded. Thus, information was obtained on the combined effects of complexity of control task and magnitude and direction of acceleration forces on pilot performance. These tests showed that the pilot's tracking performance deteriorated markedly at accelerations greater than about 4g when controlling a lightly damped vehicle. The tentative conclusion was also reached that regardless of the airframe dynamics involved, the pilot feels that in order to have the same level of control over the vehicle, an increase in the vehicle dynamic stability was required with increases in the magnitudes of the acceleration impressed upon the pilot. In another phase, boundaries of human tolerance of acceleration were established for acceleration fields such as might be encountered by a pilot flying an orbital vehicle. A special pilot restraint system was developed to increase human tolerance to longitudinal decelerations. The results of the tests showed that human tolerance

  4. FERMI&Elettra Accelerator Technical Optimization Final Report

    SciTech Connect

    Cornacchia, M.; Craievich, P.; Di Mitri, S.; Pogorelov, I.; Qiang, J.; Venturini, M.; Zholents, A.; Wang, D.; Warnock, R.; /SLAC

    2007-04-30

    This chapter describes the accelerator physics aspects, the engineering considerations and the choice of parameters that led to the accelerator design of the FERMI Free-Electron-Laser. The accelerator (also called the ''electron beam delivery system'') covers the region from the exit of the injector to the entrance of the first FEL undulator. The considerations that led to the proposed configuration were made on the basis of a study that explored various options and performance limits. This work follows previous studies of x-ray FEL facilities (SLAC LCLS [1], DESY XFEL [2], PAL XFEL [3], MIT [4], BESSY FEL [5], LBNL LUX [6], Daresbury 4GLS [7]) and integrates many of the ideas that were developed there. Several issues specific to harmonic cascade FELs, and that had not yet been comprehensively studied, were also encountered and tackled. A particularly difficult issue was the need to meet the requirement for high peak current and small slice energy spread, as the specification for the ratio of these two parameters (that defines the peak brightness of the electron beam) is almost a factor of two higher than that of the LCLS's SASE FEL. Another challenging aspect was the demand to produce an electron beam with as uniform as possible peak current and energy distributions along the bunch, a condition that was met by introducing novel beam dynamics techniques. Part of the challenge was due to the fact that there were no readily available computational tools to carry out reliable calculations, and these had to be developed. Most of the information reported in this study is available in the form of scientific publications, and is partly reproduced here for the convenience of the reader.

  5. The EMMA Accelerator, a Diagnostic Systems Overview

    SciTech Connect

    Kalinin, A.; Berg, J.; Bliss, N. Cox, G.; Dufau, M.; Gallagher, A.; Hill, C.; Jones, J.; Ma, L.; McIntosh, P.; Muratori, B.; Oates, A.; Shepherd B.; Smith, R.; Hock, K.; Holder, D.; Ibison, M., Kirkman I.; Borrell, R.; Crisp, J.; Fellenz, B.; Wendt, M.

    2011-09-04

    The 'EMMA' Non-Scaling Fixed Field Alternating Gradient (ns-FFAG) international project is currently being commissioned at Daresbury Laboratory, UK. This accelerator has been equipped with a number of diagnostic systems to facilitate this. These systems include a novel time-domain-multiplexing BPM system, moveable screen systems, a time-of-flight instrument, Faraday cups, and injection/extraction tomography sections to analyze the single bunch beams. An upgrade still to implement includes the installation of wall current monitors. This paper gives an overview of these systems and shows some data and results from the diagnostics that have contributed to the successful demonstration of a serpentine acceleration by this novel accelerator.

  6. Clinical requirements and accelerator concepts for BNCT

    SciTech Connect

    Ludewigt, B.A.; Bleuel, D.L.; Chu, W.T.; Donahue, R.J.; Kwan, J.; Leung, K.N.; Reginato, L.L.; Wells, R.P.

    1997-05-01

    Accelerator-based neutron sources are an attractive alternative to nuclear reactors for providing epithermal neutron beams for Boron Neutron Capture Therapy. Based on clinical requirements and neutronics modeling the use of proton and deuteron induced reactions in {sup 7}Li and {sup 9}Be targets has been compared. Excellent epithermal neutron beams can be produced via the {sup 7}Li(p,n){sup 7}Be reaction at proton energies of {approximately}2.5 MeV. An electrostatic quadrupole accelerator and a lithium target, which can deliver and handle 2.5 MeV protons at beam currents up to 50 mA, are under development for an accelerator-based BNCT facility at the Lawrence Berkeley National Laboratory.

  7. Accelerated stress testing of terrestrial solar cells

    NASA Technical Reports Server (NTRS)

    Lathrop, J. W.; Hawkins, D. C.; Prince, J. L.; Walker, H. A.

    1982-01-01

    The development of an accelerated test schedule for terrestrial solar cells is described. This schedule, based on anticipated failure modes deduced from a consideration of IC failure mechanisms, involves bias-temperature testing, humidity testing (including both 85-85 and pressure cooker stress), and thermal-cycle thermal-shock testing. Results are described for 12 different unencapsulated cell types. Both gradual electrical degradation and sudden catastrophic mechanical change were observed. These effects can be used to discriminate between cell types and technologies relative to their reliability attributes. Consideration is given to identifying laboratory failure modes which might lead to severe degradation in the field through second quadrant operation. Test results indicate that the ability of most cell types to withstand accelerated stress testing depends more on the manufacturer's design, processing, and worksmanship than on the particular metallization system. Preliminary tests comparing accelerated test results on encapsulated and unencapsulated cells are described.

  8. High average power linear induction accelerator development

    SciTech Connect

    Bayless, J.R.; Adler, R.J.

    1987-07-01

    There is increasing interest in linear induction accelerators (LIAs) for applications including free electron lasers, high power microwave generators and other types of radiation sources. Lawrence Livermore National Laboratory has developed LIA technology in combination with magnetic pulse compression techniques to achieve very impressive performance levels. In this paper we will briefly discuss the LIA concept and describe our development program. Our goals are to improve the reliability and reduce the cost of LIA systems. An accelerator is presently under construction to demonstrate these improvements at an energy of 1.6 MeV in 2 kA, 65 ns beam pulses at an average beam power of approximately 30 kW. The unique features of this system are a low cost accelerator design and an SCR-switched, magnetically compressed, pulse power system. 4 refs., 7 figs.

  9. Neutrino mixing in accelerated proton decays

    NASA Astrophysics Data System (ADS)

    Ahluwalia, Dharam Vir; Labun, Lance; Torrieri, Giorgio

    2016-07-01

    We discuss the inverse β-decay of accelerated protons in the context of neutrino flavor superpositions (mixings) in mass eigenstates. The process p→ n ℓ+ ν_{ℓ} is kinematically allowed because the accelerating field provides the rest energy difference between initial and final states. The rate of p→ n conversions can be evaluated in either the laboratory frame (where the proton is accelerating) or the co-moving frame (where the proton is at rest and interacts with an effective thermal bath of ℓ and ν_{ℓ} due to the Unruh effect). By explicit calculation, we show that the rates in the two frames disagree when taking into account neutrino mixings, because the weak interaction couples to charge eigenstates whereas gravity couples to neutrino mass eigenstates (D.V. Ahluwalia et al., arXiv:1505.04082 [hep-ph]). The contradiction could be resolved experimentally, potentially yielding new information on the origins of neutrino masses.

  10. Proceedings of: 2005 Particle Acceleration Confence

    SciTech Connect

    Henderson, Stuart

    2006-01-01

    The 21st Particle Accelerator Conference, PAC05, took place at the Knoxville Convention Center (KCC) from Monday through Friday, May 16-20, 2005. Sponsored by the American Physical Society (APS), the Institute of Electrics and Electronics Engineers (IEEE) with its subdivision of Nuclear and Plasma Sciences Society (NPSS), the conference was hosted by the Oak Ridge National Laboratory (ORNL) Spallation Neutron Source (SNS) Project and Thomas Jefferson National Accelerator Facility (JLab). The conference was chaired by Norbert Holtkamp, and the Local Organizing Committee was made up of staff from the ORNL SNS Project under the chairmanship of Stuart Henderson. The conference welcomed over 1400 delegates from the United States, Europe, Asia, the Middle East, South America and from as far away as Australia. Almost 1400 papers where processed during the conference and will be published on the Joint Accelerator Conferences Website (JACoW) page.

  11. Ion beam accelerator system

    NASA Technical Reports Server (NTRS)

    Aston, Graeme (Inventor)

    1984-01-01

    A system is described that combines geometrical and electrostatic focusing to provide high ion extraction efficiency and good focusing of an accelerated ion beam. The apparatus includes a pair of curved extraction grids (16, 18) with multiple pairs of aligned holes positioned to direct a group of beamlets (20) along converging paths. The extraction grids are closely spaced and maintained at a moderate potential to efficiently extract beamlets of ions and allow them to combine into a single beam (14). An accelerator electrode device (22) downstream from the extraction grids, is at a much lower potential than the grids to accelerate the combined beam.

  12. Ion beam accelerator system

    NASA Technical Reports Server (NTRS)

    Aston, G. (Inventor)

    1981-01-01

    A system is described that combines geometrical and electrostatic focusing to provide high ion extraction efficiency and good focusing of an accelerated ion beam. The apparatus includes a pair of curved extraction grids with multiple pairs of aligned holes positioned to direct a group of beamlets along converging paths. The extraction grids are closely spaced and maintained at a moderate potential to efficiently extract beamlets of ions and allow them to combine into a single beam. An accelerator electrode device downstream from the extraction grids is at a much lower potential than the grids to accelerate the combined beam. The application of the system to ion implantation is mentioned.

  13. Motion Inference During +Gz Acceleration

    DTIC Science & Technology

    2006-09-01

    AFRL-HW-WP-TP-2006-0091 Motion Inference During +Gz Acceleration Lloyd D . Tripp Jr. Richard A. McKinley Robert L. Esken Air Force Research Laboratory...5c. PROGRAM ELEMENT NUMBER 62202F 6. AUTHOR(S) 5d. PROJECT NUMBER Lloyd D . Tripp Jr 7184 Richard A. McKinley 5e. TASK NUMBER Robert L. Esken 03 5f...CD A Cj CL.C2 C 0~ 0. D 0 0~G)C00.E)’ca)4-100 ( 0 Eo12 E a 0 0L0mm 0a0 " C0 U) U) LUr o CLI.,a @ .- . : ) 0 " 0 C CL.. 70 E- 0 M 0.0 toE-C .- 0)c .2 0UL

  14. Accelerator Facilities for Radiation Research

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.

    1999-01-01

    HSRP Goals in Accelerator Use and Development are: 1.Need for ground-based heavy ion and proton facility to understand space radiation effects discussed most recently by NAS/NRC Report (1996). 2. Strategic Program Goals in facility usage and development: -(1) operation of AGS for approximately 600 beam hours/year; (2) operation of Loma Linda University (LLU) proton facility for approximately 400 beam hours/year; (3) construction of BAF facility; and (4) collaborative research at HIMAC in Japan and with other existing or potential international facilities. 3. MOA with LLU has been established to provide proton beams with energies of 40-250 important for trapped protons and solar proton events. 4. Limited number of beam hours available at Brookhaven National Laboratory's (BNL) Alternating Gradient Synchrotron (AGS).

  15. Deuterium accelerator experiments for APT.

    SciTech Connect

    Causey, Rion A. (Sandia National Laboratories, Livermore, CA); Hertz, Kristin L. (Sandia National Laboratories, Livermore, CA); Cowgill, Donald F. (Sandia National Laboratories, Livermore, CA)

    2005-08-01

    Sandia National Laboratories in California initiated an experimental program to determine whether tritium retention in the tube walls and permeation through the tubes into the surrounding coolant water would be a problem for the Accelerator Production of Tritium (APT), and to find ways to mitigate the problem, if it existed. Significant holdup in the tube walls would limit the ability of APT to meet its production goals, and high levels of permeation would require a costly cleanup system for the cooling water. To simulate tritium implantation, a 200 keV accelerator was used to implant deuterium into Al 6061-T and SS3 16L samples at temperatures and particle fluxes appropriate for APT, for times varying between one week and five months. The implanted samples were characterized to determine the deuterium retention and Permeation. During the implantation, the D(d,p)T nuclear reaction was used to monitor the build-up of deuterium in the implant region of the samples. These experiments increased in sophistication, from mono-energetic deuteron implants to multi-energetic deuteron and proton implants, to more accurately reproduce the conditions expected in APT. Micron-thick copper, nickel, and anodized aluminum coatings were applied to the front surface of the samples (inside of the APT walls) in an attempt to lower retention and permeation. The reduction in both retention and permeation produced by the nickel coatings, and the ability to apply them to the inside of the APT tubes, indicate that both nickel-coated Al 6061-T6 and nickel-coated SS3 16L tubes would be effective for use in APT. The results of this work were submitted to the Accelerator Production of Tritium project in document number TPO-E29-Z-TNS-X-00050, APT-MP-01-17.

  16. Space Experiments with Particle Accelerators: SEPAC

    NASA Technical Reports Server (NTRS)

    Burch, J. L.; Roberts, W. T.; Taylor, W. W. L.; Kawashima, N.; Marshall, J. A.; Moses, S. L.; Neubert, T.; Mende, S. B.; Choueiri, E. Y.

    1994-01-01

    The Space Experiments with Particle Accelerators (SEPAC), which flew on the Atmospheric Laboratory for Applications and Science (ATLAS) 1 mission, used new techniques to study natural phenomena in the Earth's upper atmosphere, ionosphere and magnetosphere by introducing energetic perturbations into the system from a high power electron beam with known characteristics. Properties of auroras were studied by directing the electron beam into the upper atmosphere while making measurements of optical emissions. Studies were also performed of the critical ionization velocity phenomenon.

  17. New estimation method of neutron skyshine for a high-energy particle accelerator

    NASA Astrophysics Data System (ADS)

    Oh, Joo-Hee; Jung, Nam-Suk; Lee, Hee-Seock; Ko, Seung-Kook

    2016-09-01

    A skyshine is the dominant component of the prompt radiation at off-site. Several experimental studies have been done to estimate the neutron skyshine at a few accelerator facilities. In this work, the neutron transports from a source place to off-site location were simulated using the Monte Carlo codes, FLUKA and PHITS. The transport paths were classified as skyshine, direct (transport), groundshine and multiple-shine to understand the contribution of each path and to develop a general evaluation method. The effect of each path was estimated in the view of the dose at far locations. The neutron dose was calculated using the neutron energy spectra obtained from each detector placed up to a maximum of 1 km from the accelerator. The highest altitude of the sky region in this simulation was set as 2 km from the floor of the accelerator facility. The initial model of this study was the 10 GeV electron accelerator, PAL-XFEL. Different compositions and densities of air, soil and ordinary concrete were applied in this calculation, and their dependences were reviewed. The estimation method used in this study was compared with the well-known methods suggested by Rindi, Stevenson and Stepleton, and also with the simple code, SHINE3. The results obtained using this method agreed well with those using Rindi's formula.

  18. CLASHING BEAM PARTICLE ACCELERATOR

    DOEpatents

    Burleigh, R.J.

    1961-04-11

    A charged-particle accelerator of the proton synchrotron class having means for simultaneously accelerating two separate contra-rotating particle beams within a single annular magnet structure is reported. The magnet provides two concentric circular field regions of opposite magnetic polarity with one field region being of slightly less diameter than the other. The accelerator includes a deflector means straddling the two particle orbits and acting to collide the two particle beams after each has been accelerated to a desired energy. The deflector has the further property of returning particles which do not undergo collision to the regular orbits whereby the particles recirculate with the possibility of colliding upon subsequent passages through the deflector.

  19. Vibration control in accelerators

    SciTech Connect

    Montag, C.

    2011-01-01

    In the vast majority of accelerator applications, ground vibration amplitudes are well below tolerable magnet jitter amplitudes. In these cases, it is necessary and sufficient to design a rigid magnet support structure that does not amplify ground vibration. Since accelerator beam lines are typically installed at an elevation of 1-2m above ground level, special care has to be taken in order to avoid designing a support structure that acts like an inverted pendulum with a low resonance frequency, resulting in untolerable lateral vibration amplitudes of the accelerator components when excited by either ambient ground motion or vibration sources within the accelerator itself, such as cooling water pumps or helium flow in superconducting magnets. In cases where ground motion amplitudes already exceed the required jiter tolerances, for instance in future linear colliders, passive vibration damping or active stabilization may be considered.

  20. Dielectric assist accelerating structure

    NASA Astrophysics Data System (ADS)

    Satoh, D.; Yoshida, M.; Hayashizaki, N.

    2016-01-01

    A higher-order TM02 n mode accelerating structure is proposed based on a novel concept of dielectric loaded rf cavities. This accelerating structure consists of ultralow-loss dielectric cylinders and disks with irises which are periodically arranged in a metallic enclosure. Unlike conventional dielectric loaded accelerating structures, most of the rf power is stored in the vacuum space near the beam axis, leading to a significant reduction of the wall loss, much lower than that of conventional normal-conducting linac structures. This allows us to realize an extremely high quality factor and a very high shunt impedance at room temperature. A simulation of a 5 cell prototype design with an existing alumina ceramic indicates an unloaded quality factor of the accelerating mode over 120 000 and a shunt impedance exceeding 650 M Ω /m at room temperature.

  1. Wake field acceleration experiments

    SciTech Connect

    Simpson, J.D.

    1988-01-01

    Where and how will wake field acceleration devices find use for other than, possibly, accelerators for high energy physics. I don't know that this can be responsibly answered at this time. What I can do is describe some recent results from an ongoing experimental program at Argonne which support the idea that wake field techniques and devices are potentially important for future accelerators. Perhaps this will spawn expanded interest and even new ideas for the use of this new technology. The Argonne program, and in particular the Advanced Accelerator Test Facility (AATF), has been reported in several fairly recent papers and reports. But because this is a substantially new audience for the subject, I will include a brief review of the program and the facility before describing experiments. 10 refs., 7 figs.

  2. Accelerator on a Chip

    SciTech Connect

    England, Joel

    2014-06-30

    SLAC's Joel England explains how the same fabrication techniques used for silicon computer microchips allowed their team to create the new laser-driven particle accelerator chips. (SLAC Multimedia Communications)

  3. Charged particle accelerator grating

    DOEpatents

    Palmer, R.B.

    1985-09-09

    A readily disposable and replaceable accelerator grating for a relativistic particle accelerator is described. The grating is formed for a plurality of liquid droplets that are directed in precisely positioned jet streams to periodically dispose rows of droplets along the borders of a predetermined particle beam path. A plurality of lasers are used to direct laser beams onto the droplets, at predetermined angles, thereby to excite the droplets to support electromagnetic accelerating resonances on their surfaces. Those resonances operate to accelerate and focus particles moving along the beam path. As the droplets are distorted or destroyed by the incoming radiation, they are replaced at a predetermined frequency by other droplets supplied through the jet streams.

  4. HEAVY ION LINEAR ACCELERATOR

    DOEpatents

    Van Atta, C.M.; Beringer, R.; Smith, L.

    1959-01-01

    A linear accelerator of heavy ions is described. The basic contributions of the invention consist of a method and apparatus for obtaining high energy particles of an element with an increased charge-to-mass ratio. The method comprises the steps of ionizing the atoms of an element, accelerating the resultant ions to an energy substantially equal to one Mev per nucleon, stripping orbital electrons from the accelerated ions by passing the ions through a curtain of elemental vapor disposed transversely of the path of the ions to provide a second charge-to-mass ratio, and finally accelerating the resultant stripped ions to a final energy of at least ten Mev per nucleon.

  5. Principles of Induction Accelerators

    NASA Astrophysics Data System (ADS)

    Briggs*, Richard J.

    The basic concepts involved in induction accelerators are introduced in this chapter. The objective is to provide a foundation for the more detailed coverage of key technology elements and specific applications in the following chapters. A wide variety of induction accelerators are discussed in the following chapters, from the high current linear electron accelerator configurations that have been the main focus of the original developments, to circular configurations like the ion synchrotrons that are the subject of more recent research. The main focus in the present chapter is on the induction module containing the magnetic core that plays the role of a transformer in coupling the pulsed power from the modulator to the charged particle beam. This is the essential common element in all these induction accelerators, and an understanding of the basic processes involved in its operation is the main objective of this chapter. (See [1] for a useful and complementary presentation of the basic principles in induction linacs.)

  6. Accelerator on a Chip

    ScienceCinema

    England, Joel

    2016-07-12

    SLAC's Joel England explains how the same fabrication techniques used for silicon computer microchips allowed their team to create the new laser-driven particle accelerator chips. (SLAC Multimedia Communications)

  7. DIELECTRIC WALL ACCELERATOR TECHNOLOGY

    SciTech Connect

    Sampayan, S; Caporaso, G; Chen, Y; Harris, J; Hawkins, S; Holmes, C; Nelson, S; Poole, B; Rhodes, M; Sanders, D; Sullivan, J; Wang, L; Watson, J

    2007-10-18

    The dielectric wall accelerator (DWA) is a compact pulsed power device where the pulse forming lines, switching, and vacuum wall are integrated into a single compact geometry. For this effort, we initiated a extensive compact pulsed power development program and have pursued the study of switching (gas, oil, laser induced surface flashover and photoconductive), dielectrics (ceramics and nanoparticle composites), pulse forming line topologies (asymmetric and symmetric Blumleins and zero integral pulse forming lines), and multilayered vacuum insulator (HGI) technology. Finally, we fabricated an accelerator cell for test on ETAII (a 5.5 MeV, 2 kA, 70 ns pulsewidth electron beam accelerator). We review our past results and report on the progress of accelerator cell testing.

  8. Acceleration Disturbances onboard of Geodetic Precision Space Laboratories

    NASA Astrophysics Data System (ADS)

    Peterseim, Nadja; Jakob, Flury; Schlicht, Anja

    Bartlomiej Oszczak, b@dgps.pl University of Warmia and Mazury in Olsztyn, Poland, Olsztyn, Poland Olga Maciejczyk, omaciejczyk@gmail.com Poland In this paper there is presented the study on the parameters of the ASG-EUPOS real-time RTK service NAWGEO such as: accuracy, availability, integrity and continuity. Author's model is used for tests. These parameters enable determination of the quality of received information and practical applications of the service. Paper includes also the subject related to the NAWGEO service and algorithms used in determination of mentioned parameters. The results of accuracy and precision analyses and study on availability demonstrated that NAWGEO service enables a user a position determination with a few centimeters accuracy with high probability in any moment of time.

  9. Fermi National Accelerator Laboratory Annual Program Review 1999

    SciTech Connect

    1999-05-01

    This book is submitted as one written part of the 1999 Annual DOE High Energy Physics Program Review of Fermilab, scheduled May 5-7,1999. This book should be read in conjunction with the 1999 Fermilab Workbook and the review presentations.

  10. Accelerated Laboratory Research Experience in Psychology through Simulation.

    ERIC Educational Resources Information Center

    Chatfield, Douglas C.; Cruse, Bradley H.

    1986-01-01

    Describes implementation of computer simulation to aid in training psychology students in research methodology. Four skills required in research are reviewed; the simulation's context and the software used are described; and student activities, including submission of articles to online class journals and students' responses to the method, are…

  11. Amps particle accelerator definition study

    NASA Technical Reports Server (NTRS)

    Sellen, J. M., Jr.

    1975-01-01

    The Particle Accelerator System of the AMPS (Atmospheric, Magnetospheric, and Plasmas in Space) payload is a series of charged particle accelerators to be flown with the Space Transportation System Shuttle on Spacelab missions. In the configuration presented, the total particle accelerator system consists of an energetic electron beam, an energetic ion accelerator, and both low voltage and high voltage plasma acceleration devices. The Orbiter is illustrated with such a particle accelerator system.

  12. Measurement of absolute gravity acceleration in Firenze

    NASA Astrophysics Data System (ADS)

    de Angelis, M.; Greco, F.; Pistorio, A.; Poli, N.; Prevedelli, M.; Saccorotti, G.; Sorrentino, F.; Tino, G. M.

    2011-01-01

    This paper reports the results from the accurate measurement of the acceleration of gravity g taken at two separate premises in the Polo Scientifico of the University of Firenze (Italy). In these laboratories, two separate experiments aiming at measuring the Newtonian constant and testing the Newtonian law at short distances are in progress. Both experiments require an independent knowledge on the local value of g. The only available datum, pertaining to the italian zero-order gravity network, was taken more than 20 years ago at a distance of more than 60 km from the study site. Gravity measurements were conducted using an FG5 absolute gravimeter, and accompanied by seismic recordings for evaluating the noise condition at the site. The absolute accelerations of gravity at the two laboratories are (980 492 160.6 ± 4.0) μGal and (980 492 048.3 ± 3.0) μGal for the European Laboratory for Non-Linear Spectroscopy (LENS) and Dipartimento di Fisica e Astronomia, respectively. Other than for the two referenced experiments, the data here presented will serve as a benchmark for any future study requiring an accurate knowledge of the absolute value of the acceleration of gravity in the study region.

  13. Designing reliability into accelerators

    NASA Astrophysics Data System (ADS)

    Hutton, A.

    1992-07-01

    Future accelerators will have to provide a high degree of reliability. Quality must be designed in right from the beginning and must remain a central theme throughout the project. The problem is similar to the problems facing US industry today, and examples of the successful application of quality engineering will be given. Different aspects of an accelerator project will be addressed: Concept, Design, Motivation, Management Techniques, and Fault Diagnosis. The importance of creating and maintaining a coherent team will be stressed.

  14. Microgravity Acceleration Measurement System

    NASA Technical Reports Server (NTRS)

    Foster, William

    2009-01-01

    Microgravity Acceleration Measurement System (MAMS) is an ongoing study of the small forces (vibrations and accelerations) on the ISS that result from the operation of hardware, crew activities, as well as dockings and maneuvering. Results will be used to generalize the types of vibrations affecting vibration-sensitive experiments. Investigators seek to better understand the vibration environment on the space station to enable future research.

  15. CEBAF Accelerator Achievements

    NASA Astrophysics Data System (ADS)

    Chao, Y. C.; Drury, M.; Hovater, C.; Hutton, A.; Krafft, G. A.; Poelker, M.; Reece, C.; Tiefenback, M.

    2011-05-01

    In the past decade, nuclear physics users of Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) have benefited from accelerator physics advances and machine improvements. As of early 2011, CEBAF operates routinely at 6 GeV, with a 12 GeV upgrade underway. This article reports highlights of CEBAF's scientific and technological evolution in the areas of cryomodule refurbishment, RF control, polarized source development, beam transport for parity experiments, magnets and hysteresis handling, beam breakup, and helium refrigerator operational optimization.

  16. Rolamite acceleration sensor

    DOEpatents

    Abbin, Joseph P.; Briner, Clifton F.; Martin, Samuel B.

    1993-01-01

    A rolamite acceleration sensor which has a failsafe feature including a housing, a pair of rollers, a tension band wrapped in an S shaped fashion around the rollers, wherein the band has a force-generation cut out and a failsafe cut out or weak portion. The failsafe cut out or weak portion breaks when the sensor is subjected to an excessive acceleration so that the sensor fails in an open circuit (non-conducting) state permanently.

  17. Rolamite acceleration sensor

    DOEpatents

    Abbin, J.P.; Briner, C.F.; Martin, S.B.

    1993-12-21

    A rolamite acceleration sensor is described which has a failsafe feature including a housing, a pair of rollers, a tension band wrapped in an S shaped fashion around the rollers, wherein the band has a force-generation cut out and a failsafe cut out or weak portion. The failsafe cut out or weak portion breaks when the sensor is subjected to an excessive acceleration so that the sensor fails in an open circuit (non-conducting) state permanently. 6 figures.

  18. Collective field accelerator

    DOEpatents

    Luce, John S.

    1978-01-01

    A collective field accelerator which operates with a vacuum diode and utilizes a grooved cathode and a dielectric anode that operates with a relativistic electron beam with a .nu./.gamma. of .about. 1, and a plurality of dielectric lenses having an axial magnetic field thereabout to focus the collectively accelerated electrons and ions which are ejected from the anode. The anode and lenses operate as unoptimized r-f cavities which modulate and focus the beam.

  19. Application of positron annihilation lifetime spectroscopy (PALS) to study the nanostructure in amphiphile self-assembly materials: phytantriol cubosomes and hexosomes.

    PubMed

    Dong, Aurelia W; Fong, Celesta; Waddington, Lynne J; Hill, Anita J; Boyd, Ben J; Drummond, Calum J

    2015-01-21

    Self-assembled amphiphile nanostructures of colloidal dimensions such as cubosomes and hexosomes are of interest as delivery vectors in pharmaceutical and nanomedicine applications. Translation would be assisted through a better of understanding of the effects of drug loading on the internal nanostructure, and the relationship between this nanostructure and drug release profile. Positron annihilation lifetime spectroscopy (PALS) is sensitive to local microviscosity and is used as an in situ molecular probe to examine the Q2 (cubosome) → H2 (hexosome) → L2 phase transitions of the pharmaceutically relevant phytantriol-water system in the presence of a model hydrophobic drug, vitamin E acetate (VitEA). It is shown that the ortho-positronium lifetime (τ) is sensitive to molecular packing and mobility and this has been correlated with the rheological properties of individual lyotropic liquid crystalline mesophases. Characteristic PALS lifetimes for L2 (τ4∼ 4 ns) ∼ H2 (τ4∼ 4 ns) > Q(2 Pn3m) (τ4∼ 2.2 ns) are observed for the phytantriol-water system, with the addition of VitEA yielding a gradual increase in τ from τ∼ 2.2 ns for cubosomes to τ∼ 3.5 ns for hexosomes. The dynamic chain packing at higher temperatures and in the L2 and H2 phases is qualitatively less "viscous", consistent with rheological measurements. This information offers increased understanding of the relationship between internal nanostructure and species permeability.

  20. Accelerators for America's Future

    NASA Astrophysics Data System (ADS)

    Bai, Mei

    2016-03-01

    Particle accelerator, a powerful tool to energize beams of charged particles to a desired speed and energy, has been the working horse for investigating the fundamental structure of matter and fundermental laws of nature. Most known examples are the 2-mile long Stanford Linear Accelerator at SLAC, the high energy proton and anti-proton collider Tevatron at FermiLab, and Large Hadron Collider that is currently under operation at CERN. During the less than a century development of accelerator science and technology that led to a dazzling list of discoveries, particle accelerators have also found various applications beyond particle and nuclear physics research, and become an indispensible part of the economy. Today, one can find a particle accelerator at almost every corner of our lives, ranging from the x-ray machine at the airport security to radiation diagnostic and therapy in hospitals. This presentation will give a brief introduction of the applications of this powerful tool in fundermental research as well as in industry. Challenges in accelerator science and technology will also be briefly presented

  1. Virtual Laboratories

    NASA Astrophysics Data System (ADS)

    Hut, P.

    At the frontier of most areas in science, computer simulations playa central role. The traditional division of natural science into experimental and theoretical investigations is now completely outdated. Instead, theory, simulation, and experimentation form three equally essential aspects, each with its own unique flavor and challenges. Yet, education in computational science is still lagging far behind, and the number of text books in this area is minuscule compared to the many text books on theoretical and experimental science. As a result, many researchers still carry out simulations in a haphazard way, without properly setting up the computational equivalent of a well equipped laboratory. The art of creating such a virtual laboratory, while providing proper extensibility and documentation, is still in its infancy. A new approach is described here, Open Knowledge, as an extension of the notion of Open Source software. Besides open source code, manuals, and primers, an open knowledge project provides simulated dialogues between code developers, thus sharing not only the code, but also the motivations behind the code.

  2. Kr II Laser-Induced Fluorescence for Measuring Plasma Acceleration (Preprint)

    DTIC Science & Technology

    2012-02-01

    krypton as a diagnostic technique for quantifying the electrostatic acceleration within the discharge of a laboratory cross-field plasma accelerator...velocity as the krypton ions are accelerated from near rest to approximately 21 km/s (190 eV). Ion temperature and the ion velocity distributions...present the application of laser-induced fluorescence of singly ionized krypton as a diagnostic technique for quantifying the electrostatic acceleration

  3. Internal consistency, concurrent validity, and discriminant validity of a measure of public support for policies for active living in transportation (PAL-T) in a population-based sample of adults.

    PubMed

    Fuller, Daniel; Gauvin, Lise; Fournier, Michel; Kestens, Yan; Daniel, Mark; Morency, Patrick; Drouin, Louis

    2012-04-01

    Active living is a broad conceptualization of physical activity that incorporates domains of exercise; recreational, household, and occupational activities; and active transportation. Policy makers develop and implement a variety of transportation policies that can influence choices about how to travel from one location to another. In making such decisions, policy makers act in part in response to public opinion or support for proposed policies. Measures of the public's support for policies aimed at promoting active transportation can inform researchers and policy makers. This study examined the internal consistency, and concurrent and discriminant validity of a newly developed measure of the public's support for policies for active living in transportation (PAL-T). A series of 17 items representing potential policies for promoting active transportation was generated. Two samples of participants (n = 2,001 and n = 2,502) from Montreal, Canada, were recruited via random digit dialling. Analyses were conducted on the combined data set (n = 4,503). Participants were aged 18 through 94 years (58% female). The concurrent and discriminant validity of the PAL-T was assessed by examining relationships with physical activity and smoking. To explore the usability of the PAL-T, predicted scale scores were compared to the summed values of responses. Results showed that the internal consistency of the PAL-T was 0.70. Multilevel regression demonstrated no relationship between the PAL-T and smoking status (p > 0.05) but significant relationships with utilitarian walking (p < 0.05) and cycling (p < 0.01) for at least 30 minutes on 5 days/week. The PAL-T has acceptable internal consistency and good concurrent and discriminant validity. Measuring public opinion can inform policy makers and support advocacy efforts aimed at making built environments more suitable for active transportation while allowing researchers to examine the antecedents and

  4. Computational studies and optimization of wakefield accelerators

    SciTech Connect

    Tsung, Frank S.; Bruhwiler, David L.; Cary, John R.; Esarey, Eric H.; Mori, Warren B.; Vay, Jean-Luc; Martins, Samuel F.; Katsouleas, Tom; Cormier-Michel, Estelle; Fawley, William M.; Huang, Chengkun; Wang, Xiadong; Cowan, Ben; Decyk, Victor K.; Fonseca, Ricardo A.; Lu, Wei; Messmer, Peter; Mullowney, Paul; Nakamura, Kei; Paul, Kevin; Plateau, Guillaume R.; Schroeder, Carl B.; Silva, Luis O.; Toth, Csaba; Geddes, C.G.R.; Tzoufras, Michael; Antonsen, Tom; Vieira, Jorge; Leemans, Wim P.

    2008-06-16

    Laser- and particle beam-driven plasma wakefield accelerators produce accelerating fields thousands of times higher than radio-frequency accelerators, offering compactness and ultrafast bunches to extend the frontiers of high energy physics and to enable laboratory-scale radiation sources. Large-scale kinetic simulations provide essential understanding of accelerator physics to advance beam performance and stability and show and predict the physics behind recent demonstration of narrow energy spread bunches. Benchmarking between codes is establishing validity of the models used and, by testing new reduced models, is extending the reach of simulations to cover upcoming meter-scale multi-GeV experiments. This includes new models that exploit Lorentz boosted simulation frames to speed calculations. Simulations of experiments showed that recently demonstrated plasma gradient injection of electrons can be used as an injector to increase beam quality by orders of magnitude. Simulations are now also modeling accelerator stages of tens of GeV, staging of modules, and new positron sources to design next-generation experiments and to use in applications in high energy physics and light sources.

  5. Introductory labs on the vector nature of force and acceleration

    NASA Astrophysics Data System (ADS)

    Kanim, Stephen E.; Subero, Keron

    2010-05-01

    We discuss the use of long-exposure digital photography in introductory mechanics laboratories. Students at New Mexico State University use inexpensive digital cameras to record the motion of objects with attached blinking light emitting diodes. These photographs are used to make inferences about the velocity and acceleration of the moving object. We use the analysis of these photographs to promote student understanding of the vector nature of kinematics quantities. In subsequent laboratories we build on this understanding to help students relate the acceleration vector for a moving object to the net force vector for that object. We give details about the equipment we use and describe the sequence of activities that we have developed for a two-dimensional motion laboratory and for a laboratory on Newton's second law. Finally we present some pre- and post-test data on questions related to the concepts underlying these laboratories.

  6. Tethered gravity laboratories study

    NASA Technical Reports Server (NTRS)

    Lucchetti, F.

    1990-01-01

    The scope of the study is to investigate ways of controlling the microgravity environment of the International Space Station by means of a tethered system. Four main study tasks were performed. First, researchers analyzed the utilization of the tether systems to improve the lowest possible steady gravity level on the Space Station and the tether capability to actively control the center of gravity position in order to compensate for activities that would upset the mass distribution of the Station. The purpose of the second task was to evaluate the whole of the experiments performable in a variable gravity environment and the related beneficial residual accelerations, both for pure and applied research in the fields of fluid, materials, and life science, so as to assess the relevance of a variable g-level laboratory. The third task involves the Tethered Variable Gravity Laboratory. The use of the facility that would crawl along a deployed tether and expose experiments to varying intensities of reduced gravity is discussed. Last, a study performed on the Attitude Tether Stabilizer concept is discussed. The stabilization effect of ballast masses tethered to the Space Station was investigated as a means of assisting the attitude control system of the Station.

  7. Laboratory investigations

    NASA Technical Reports Server (NTRS)

    Russell, Ray W.

    1988-01-01

    Laboratory studies related to cometary grains and the nuclei of comets can be broken down into three areas which relate to understanding the spectral properties, the formation mechanisms, and the evolution of grains and nuclei: (1) Spectral studies to be used in the interpretation of cometary spectra; (2) Sample preparation experiments which may shed light on the physical nature and history of cometary grains and nuclei by exploring the effects on grain emissivities resulting from the ways in which the samples are created; and (3) Grain processing experiments which should provide insight on the interaction of cometary grains with the environment in the immediate vicinity of the cometary nucleus as the comet travels from the Oort cloud through perihelion, and perhaps even suggestions regarding the relationship between interstellar grains and cometary matter. A summary is presented with a different view of lab experiments than is found in the literature, concentrating on measurement techniques and sample preparations especially relevant to cometary dust.

  8. Laser Ion Acceleration Control

    NASA Astrophysics Data System (ADS)

    Kawata, Shigeo; Nagashima, T.; Izumiyama, T.; Sato, D.; Takano, M.; Barada, D.; Ma, Y. Y.; Gu, Y. J.; Kong, Q.; Wang, P. X.; Wang, W. M.

    2013-10-01

    An intense femtosecond pulsed laser is employed to accelerate ions. The issues in the laser ion accelerator include the energy efficiency from the laser to the ions, the ion beam collimation, the ion energy spectrum control, the ion beam bunching, the ion particle energy control, etc. In the study particle computer simulations were performed to solve the issues, and each component was designed to control the ion beam quality. When an intense laser illuminates a target, electrons in the target are accelerated and leave from the target; temporarily a strong electric field is formed between the high-energy electrons and the target ions, and the target ions are accelerated. The energy efficiency from the laser to ions was improved by using a solid target with a fine sub-wavelength structure or by a near critical density gas plasma. The ion beam collimation was realized by holes behind the solid target. The control of the ion energy spectrum and the ion particle energy, and the ion beam bunching were successfully realized by a multi-stage laser-target interaction. The present study proposed a novel concept for a future compact laser ion accelerator, based on each component study required to control the ion beam quality and parameters. Partly supported by JSPS, MEXT, CORE, Japan/US Cooperation program, ASHULA and ILE/Osaka University.

  9. Dielectric laser accelerators

    NASA Astrophysics Data System (ADS)

    England, R. Joel; Noble, Robert J.; Bane, Karl; Dowell, David H.; Ng, Cho-Kuen; Spencer, James E.; Tantawi, Sami; Wu, Ziran; Byer, Robert L.; Peralta, Edgar; Soong, Ken; Chang, Chia-Ming; Montazeri, Behnam; Wolf, Stephen J.; Cowan, Benjamin; Dawson, Jay; Gai, Wei; Hommelhoff, Peter; Huang, Yen-Chieh; Jing, Chunguang; McGuinness, Christopher; Palmer, Robert B.; Naranjo, Brian; Rosenzweig, James; Travish, Gil; Mizrahi, Amit; Schachter, Levi; Sears, Christopher; Werner, Gregory R.; Yoder, Rodney B.

    2014-10-01

    The use of infrared lasers to power optical-scale lithographically fabricated particle accelerators is a developing area of research that has garnered increasing interest in recent years. The physics and technology of this approach is reviewed, which is referred to as dielectric laser acceleration (DLA). In the DLA scheme operating at typical laser pulse lengths of 0.1 to 1 ps, the laser damage fluences for robust dielectric materials correspond to peak surface electric fields in the GV /m regime. The corresponding accelerating field enhancement represents a potential reduction in active length of the accelerator between 1 and 2 orders of magnitude. Power sources for DLA-based accelerators (lasers) are less costly than microwave sources (klystrons) for equivalent average power levels due to wider availability and private sector investment. Because of the high laser-to-particle coupling efficiency, required pulse energies are consistent with tabletop microJoule class lasers. Combined with the very high (MHz) repetition rates these lasers can provide, the DLA approach appears promising for a variety of applications, including future high-energy physics colliders, compact light sources, and portable medical scanners and radiative therapy machines.

  10. Electrostatic Plasma Accelerator (EPA)

    NASA Technical Reports Server (NTRS)

    Brophy, John R.; Aston, Graeme

    1989-01-01

    The Electrostatic Plasma Accelerator (EPA) is a thruster concept which promises specific impulse levels between low power arcjets and those of the ion engine while retaining the relative simplicity of the arcjet. The EPA thruster produces thrust through the electrostatic acceleration of a moderately dense plasma. No accelerating electrodes are used and the specific impulse is a direct function of the applied discharge voltage and the propellant atomic mass. The goal of the present program is to demonstrate feasibility of the EPA thruster concept through experimental and theoretical investigations of the EPA acceleration mechanism and discharge chamber performance. Experimental investigations will include operating the test bed ion (TBI) engine as an EPA thruster and parametrically varying the thruster geometry and operating conditions to quantify the electrostatic plasma acceleration effect. The theoretical investigations will include the development of a discharge chamber model which describes the relationships between the engine size, plasma properties, and overall performance. For the EPA thruster to be a viable propulsion concept, overall thruster efficiencies approaching 30% with specific impulses approaching 1000 s must be achieved.

  11. Advanced accelerator theory development

    SciTech Connect

    Sampayan, S.E.; Houck, T.L.; Poole, B.; Tishchenko, N.; Vitello, P.A.; Wang, I.

    1998-02-09

    A new accelerator technology, the dielectric wall accelerator (DWA), is potentially an ultra compact accelerator/pulsed power driver. This new accelerator relies on three new components: the ultra-high gradient insulator, the asymmetric Blumlein and low jitter switches. In this report, we focused our attention on the first two components of the DWA system the insulators and the asymmetric Blumlein. First, we sought to develop the necessary design tools to model and scale the behavior of the high gradient insulator. To perform this task we concentrated on modeling the discharge processes (i.e., initiation and creation of the surface discharge). In addition, because these high gradient structures exhibit favorable microwave properties in certain accelerator configurations, we performed experiments and calculations to determine the relevant electromagnetic properties. Second, we performed circuit modeling to understand energy coupling to dynamic loads by the asymmetric Blumlein. Further, we have experimentally observed a non-linear coupling effect in certain asymmetric Blumlein configurations. That is, as these structures are stacked into a complete module, the output voltage does not sum linearly and a lower than expected output voltage results. Although we solved this effect experimentally, we performed calculations to understand this effect more fully to allow better optimization of this DWA pulse-forming line system.

  12. Summary report of working group 4: Beam-driven acceleration

    NASA Astrophysics Data System (ADS)

    Litos, M.; Jing, C.

    2017-03-01

    Despite the urgent need for a TeV-class linear collider in High-Energy Physics (HEP), a clear path to buildable and affordable accelerator technologies has yet to be realized. Clearly, the identification and advancement of next generation accelerator technologies for a linear collider have been one of the main charges since the inception of the Advanced Accelerator Concepts (AAC) workshop. The fundamental requirements of linear colliders for accelerator technologies are to demonstrate high wall-plug efficiency, high beam quality preservation, high effective gradient, scalability, etc. Within the AAC community, beam-driven wakefield acceleration schemes (the central subject of Working Group 4) are always promising and attractive approaches. Since the last AAC workshop, a few high profile experiments related to beam-driven plasma wakefield acceleration have been conducted at the SLAC National Accelerator Laboratory's FACET facility. These experiments have successfully answered questions related to obtaining high beam energy transfer efficiency, demonstrating high gradient positron acceleration, and demonstrating high quality witness beam acceleration. Research on beam-driven structure-based wakefield acceleration has also demonstrated significant results for high gradient acceleration, including longitudinal bunch shaping for high efficiency and beam breakup control. As an important application or a stepping-stone facility, beam-driven plasma or structure-based wakefield accelerators for 5th generation FEL light sources have attracted broad attention. Studies have been undertaken on various aspects, ranging from the overall parameterizations to detailed beam generation and control technologies. Other related applications, such as high power RF and THz generation, beam modulation and energy chirp compensation, are also within the scope of our Working Group. In summary, WG4 examined the advancement of beam-driven wakefield accelerators (plasma and structure-based) in

  13. Plasma-based accelerator structures

    SciTech Connect

    Schroeder, Carl B.

    1999-12-01

    Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas.

  14. HF Accelerated Electron Fluxes, Spectra, and Ionization

    NASA Astrophysics Data System (ADS)

    Carlson, Herbert C.; Jensen, Joseph B.

    2015-10-01

    Wave particle interactions, an essential aspect of laboratory, terrestrial, and astrophysical plasmas, have been studied for decades by transmitting high power HF radio waves into Earth's weakly ionized space plasma, to use it as a laboratory without walls. Application to HF electron acceleration remains an active area of research (Gurevich in Usp Fizicheskikh Nauk 177(11):1145-1177, 2007) today. HF electron acceleration studies began when plasma line observations proved (Carlson et al. in J Atmos Terr Phys 44:1089-1100, 1982) that high power HF radio wave-excited processes accelerated electrons not to ~eV, but instead to -100 times thermal energy (10 s of eV), as a consequence of inelastic collision effects on electron transport. Gurevich et al (J Atmos Terr Phys 47:1057-1070, 1985) quantified the theory of this transport effect. Merging experiment with theory in plasma physics and aeronomy, enabled prediction (Carlson in Adv Space Res 13:1015-1024, 1993) of creating artificial ionospheres once ~GW HF effective radiated power could be achieved. Eventual confirmation of this prediction (Pedersen et al. in Geophys Res Lett 36:L18107, 2009; Pedersen et al. in Geophys Res Lett 37:L02106, 2010; Blagoveshchenskaya et al. in Ann Geophys 27:131-145, 2009) sparked renewed interest in optical inversion to estimate electron spectra in terrestrial (Hysell et al. in J Geophys Res Space Phys 119:2038-2045, 2014) and planetary (Simon et al. in Ann Geophys 29:187-195, 2011) atmospheres. Here we present our unpublished optical data, which combined with our modeling, lead to conclusions that should meaningfully improve future estimates of the spectrum of HF accelerated electron fluxes. Photometric imaging data can significantly improve detection of emissions near ionization threshold, and confirm depth of penetration of accelerated electrons many km below the excitation altitude. Comparing observed to modeled emission altitude shows future experiments need electron density profiles

  15. Perturbations for transient acceleration

    SciTech Connect

    Vargas, Cristofher Zuñiga; Zimdahl, Winfried; Hipólito-Ricaldi, Wiliam S. E-mail: hipolito@ceunes.ufes.br

    2012-04-01

    According to the standard ΛCDM model, the accelerated expansion of the Universe will go on forever. Motivated by recent observational results, we explore the possibility of a finite phase of acceleration which asymptotically approaches another period of decelerated expansion. Extending an earlier study on a corresponding homogeneous and isotropic dynamics, in which interactions between dark matter and dark energy are crucial, the present paper also investigates the dynamics of the matter perturbations both on the Newtonian and General Relativistic (GR) levels and quantifies the potential relevance of perturbations of the dark-energy component. In the background, the model is tested against the Supernova type Ia (SNIa) data of the Constitution set and on the perturbative level against growth rate data, among them those of the WiggleZ survey, and the data of the 2dFGRS project. Our results indicate that a transient phase of accelerated expansion is not excluded by current observations.

  16. Uniform acceleration in general relativity

    NASA Astrophysics Data System (ADS)

    Friedman, Yaakov; Scarr, Tzvi

    2015-10-01

    We extend de la Fuente and Romero's (Gen Relativ Gravit 47:33, 2015) defining equation for uniform acceleration in a general curved spacetime from linear acceleration to the full Lorentz covariant uniform acceleration. In a flat spacetime background, we have explicit solutions. We use generalized Fermi-Walker transport to parallel transport the Frenet basis along the trajectory. In flat spacetime, we obtain velocity and acceleration transformations from a uniformly accelerated system to an inertial system. We obtain the time dilation between accelerated clocks. We apply our acceleration transformations to the motion of a charged particle in a constant electromagnetic field and recover the Lorentz-Abraham-Dirac equation.

  17. Galactic Cosmic Ray Simulator at the NASA Space Radiation Laboratory

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Slaba, Tony C.; Rusek, Adam

    2015-01-01

    The external Galactic Cosmic Ray (GCR) spectrum is significantly modified when it passes through spacecraft shielding and astronauts. One approach for simulating the GCR space radiation environment is to attempt to reproduce the unmodified, external GCR spectrum at a ground based accelerator. A possibly better approach would use the modified, shielded tissue spectrum, to select accelerator beams impinging on biological targets. NASA plans for implementation of a GCR simulator at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory will be discussed.

  18. Microelectromechanical acceleration-sensing apparatus

    DOEpatents

    Lee, Robb M.; Shul, Randy J.; Polosky, Marc A.; Hoke, Darren A.; Vernon, George E.

    2006-12-12

    An acceleration-sensing apparatus is disclosed which includes a moveable shuttle (i.e. a suspended mass) and a latch for capturing and holding the shuttle when an acceleration event is sensed above a predetermined threshold level. The acceleration-sensing apparatus provides a switch closure upon sensing the acceleration event and remains latched in place thereafter. Examples of the acceleration-sensing apparatus are provided which are responsive to an acceleration component in a single direction (i.e. a single-sided device) or to two oppositely-directed acceleration components (i.e. a dual-sided device). A two-stage acceleration-sensing apparatus is also disclosed which can sense two acceleration events separated in time. The acceleration-sensing apparatus of the present invention has applications, for example, in an automotive airbag deployment system.

  19. Diffusive Shock Acceleration

    NASA Astrophysics Data System (ADS)

    Baring, Matthew

    2003-04-01

    The process of diffusive acceleration of charged particles in shocked plasmas is widely invoked in astrophysics to account for the ubiquitous presence of signatures of non-thermal relativistic electrons and ions in the universe. This statistical energization mechanism, manifested in turbulent media, was first posited by Enrico Fermi in 1949 to explain the observed cosmic ray population, which exhibits an almost power-law distribution in rigidity. The absence of a momentum scale is a key characteristic of diffusive shock acceleration, and astrophysical systems generally only impose scales at the injection (low energy) and loss (high energy) ends of the particle spectrum. The existence of structure in the cosmic ray spectrum (the "knee") at around 3000 TeV has promoted contentions that there are at least two origins for cosmic rays, a galactic one supplying those up to the knee, and perhaps an extragalactic one that can explain even the ultra-high energy cosmic rays (UHECRs) seen at 1-300 EeV. Accounting for the UHECRs with familiar astrophysical sites of acceleration has historically proven difficult due to the need to assume high magnetic fields in order to reduce the shortest diffusive acceleration timescale, the ion gyroperiod, to meaningful values. Yet active galaxies and gamma-ray bursts remain strong and interesting candidate sources for UHECRs, turning the theoretical focus to relativistic shocks. This review summarizes properties of diffusive shock acceleration that are salient to the issue of UHECR generation. These include spectral indices, anisotropies, acceleration efficencies and timescales, as functions of the shock speed and mean field orientation, and also the degree of field turbulence. Astrophysical sites for UHECR production are also critiqued.

  20. 'Light Sail' Acceleration Reexamined

    SciTech Connect

    Macchi, Andrea; Veghini, Silvia; Pegoraro, Francesco

    2009-08-21

    The dynamics of the acceleration of ultrathin foil targets by the radiation pressure of superintense, circularly polarized laser pulses is investigated by analytical modeling and particle-in-cell simulations. By addressing self-induced transparency and charge separation effects, it is shown that for 'optimal' values of the foil thickness only a thin layer at the rear side is accelerated by radiation pressure. The simple 'light sail' model gives a good estimate of the energy per nucleon, but overestimates the conversion efficiency of laser energy into monoenergetic ions.