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Sample records for 5370b resolution ps

  1. 400-ps time resolution with a passively quenched avalanche photodiode.

    PubMed

    Grayson, T P; Wang, L J

    1993-06-01

    Avalanche photodiodes (APD's) operated in a single-photon-counting Geiger mode are becoming attractive alternatives to photomultiplier tubes for low-light-level detection and signal timing. By paying careful attention to the design and construction of a simple APD passive quenching circuit to reduce stray capacitances, we directly measured a time resolution of 410 ps FWHM for a commercial APD. A more detailed data analysis shows the actual time resolution to be ~ 390 ps FWHM. This is believed to be the most accurate time response for such a simple, inexpensive, and widely available device achieved to date. PMID:20829894

  2. High-resolution PS-OCT of Enamel Remineralization

    PubMed Central

    Can, Anna M.; Darling, Cynthia L.; Fried, Daniel

    2011-01-01

    Previous studies have demonstrated that Polarization Sensitive Optical Coherence Tomography (PS-OCT) can be used to image the remineralization of early artificial caries lesions. However, the depth resolution of the imaging system employed in those previous studies was limited and the outer surface structure of the lesions were not resolved as clearly as desired. The purpose of this study was to repeat the earlier remineralization study using a broadband light-source of higher resolution to determine if there can be improved resolution of the remineralized surface zones of the lesions. An all polarization-maintaining fiber based PS-OCT system operating at 1310-nm was used to acquire polarization resolved images of bovine enamel surfaces exposed to a demineralizing solution at pH-4.9 followed by a fluoride containing remineralizing solution at pH-7.0 containing 2-ppm fluoride. The structure of the surface zones could be clearly resolved using PS-OCT in the samples that underwent remineralization. The PS-OCT measurements indicated a significant (p<0.05) reduction in the integrated reflectivity between the severity of the lesions that were exposed to the remineralization solution and those that were not. The lesion depth and mineral loss were also measured with polarized light microscopy and transverse microradiography after sectioning the enamel blocks. These results show that PS-OCT can be used to non-destructively monitor the remineralization potential of anti-caries agents. PMID:21909226

  3. Four-frame gated optical imager with 120-ps resolution

    SciTech Connect

    Young, P.E.; Hares, J.D.; Kilkenny, J.D.; Phillion, D.W.; Campbell, E.M.

    1987-08-11

    In this paper we describe a framing camera capable of four separate two-dimensional images with each frame having a 120-ps gate width. The time separation between frames can be selected arbitrarily. Fast gating of a single frame is accomplished by using a standard wafer image intensifier tube in which the cathode is capacitively coupled to a conducting mesh placed over the input window of the tube. The mesh is then pulsed relative to the microchannel plate by a narrow (120 ps), high-voltage pulse. The transmission of the tube as a function of time has been verified using a laser-diode pulser and is approximately Gaussian with a FWHM of 120 ps. Multiple frames are obtained using multiple gated tubes which can then share a single bias supply and pulser with relative gate times selected by the cable lengths between the tubes and the pulser. A beamsplitter system has been constructed which produces a separate image for each tube from a single scene. In the present system, the tubes use S-20 photocathodes with an 18 mm diameter and quartz input windows. Spatial resolution is unchanged between d.c. and fast gated operations and has been measured to 10 lp/mm. Applications to time-dependent behavior in laser-produced plasmas will be presented. 7 figs.

  4. Study on GASTOF - A 10 ps resolution timing detector

    NASA Astrophysics Data System (ADS)

    Bonnet, Luc; Liao, Junhui; Piotrzkowski, Krzysztof

    2014-10-01

    GASTOF (Gas Time Of Flight) is a type of fast-time detector affiliated to the HPS (High Precision Spectrometer) project which is a forward physics collaborator within CMS. It is a picosecond time resolution Cherenkov gas detector using very fast single anode micro-channel plate photomultiplier (Hamamatsu R3809U-50 or Photek 210) as a photon detector. We firstly measured characteristics of these two types of MCP-PMTs by a fast laser pulse in lab. Then two GASTOF detectors both equipped with a Hamamatsu R3809U-50 tube were studied in a beam test at CERN. According to the analysis of beam test data, the average number of photoelectrons (phe) was 2.0 for both phototubes. By making a cut on the number of photoelectrons such that the mean phe was 3.6 in one phototube and 3.2 in another, we obtained a time resolution of σ ~ 11.7 picosecond (ps) and σ ~ 8.2 ps.

  5. Four-frame gated optical imager with 120-ps resolution

    SciTech Connect

    Young, P.E.; Hares, J.D.; Kilkenny, J.D.; Phillion, D.W.; Campbell, E.M.

    1988-04-01

    In this paper we describe the operation and applications of a framing camera capable of four separate two-dimensional images with each frame having a 120-ps gate width. Fast gating of a single frame is accomplished by using a wafer image intensifier tube in which the cathode is capacitively coupled to an external electrode placed outside of the photocathode of the tube. This electrode is then pulsed relative to the microchannel plate by a narrow (120 ps), high-voltage pulse. Multiple frames are obtained by using multiple gated tubes which share a single bias supply and pulser with relative gate times selected by the cable lengths between the tubes and the pulser. A beamsplitter system has been constructed which produces a separate image for each tube from a single scene. Applications of the framing camera to inertial confinement fusion experiments are discussed.

  6. A multichannel time-to-digital converter ASIC with better than 3 ps RMS time resolution

    NASA Astrophysics Data System (ADS)

    Perktold, L.; Christiansen, J.

    2014-01-01

    The development of a new multichannel, fine-time resolution time-to-digital converter (TDC) ASIC is currently under development at CERN. A prototype TDC has been designed, fabricated and successfully verified with demonstrated time resolutions of better than 3 ps-rms. Least-significant-bit (LSB) sizes as small as 5 ps with a differential-non-linearity (DNL) of better than ±0.9 LSB and integral-non-linearity (INL) of better than ±1.3 LSB respectively have been achieved. The contribution describes the implemented architecture and presents measurement results of a prototype ASIC implemented in a commercial 130 nm technology.

  7. Directed self-assembly materials for high resolution beyond PS-b-PMMA

    NASA Astrophysics Data System (ADS)

    Hirahara, Eri; Paunescu, Margareta; Polishchuk, Orest; Jeong, EunJeong; Ng, Edward; Shan, Jianhui; Yin, Jian; Kim, Jihoon; Cao, Yi; Li, Jin; Hong, SungEun; Baskaran, Durairaj; Lin, Guanyang

    2016-03-01

    To extend directed self-assembly (DSA) of poly(styrene-b-methyl methacrylate) (PS-b-PMMA) for higher resolution, placement accuracy and potentially improved pattern line edge roughness (LER), we have developed a next-generation material platform of organic high-χ block copolymers ("HC series", AZEMBLYTM EXP PME-3000 series). The new material platform has a built-in orientation control mechanism which enables block copolymer domains to vertically selforient without topcoat/additive or delicate solvent vapor annealing. Furthermore, sub-10 nm lines and spaces (L/S) patterning by two major chemoepitaxy DSA, LiNe and SMARTTM processes, was successfully implemented on 12" wafer substrates by using the PME-3000 lamellar series. The results revealed that the new material platform is compatible with the existing PS-b-PMMA-based chemical prepatterns and standard protocols. We also introduced the built-in orientation control strategy to the conventional PS-b-PMMA system, producing a new generation of PS-b-PMMA materials with facile orientation control. The modified PS-b-PMMA (m-PS-b-PMMA) performed LiNe flow DSA yielding a comparable CD process window with improved LER/LWR/SWR after the L/S patterns were transferred into a Si substrate.

  8. 100 ps time resolution with thin silicon pixel detectors and a SiGe HBT amplifier

    NASA Astrophysics Data System (ADS)

    Benoit, M.; Cardarelli, R.; Débieux, S.; Favre, Y.; Iacobucci, G.; Nessi, M.; Paolozzi, L.; Shu, K.

    2016-03-01

    A 100 μm thick silicon detector with 1 mm2 pad readout optimized for sub-nanosecond time resolution has been developed and tested. Coupled to a purposely developed amplifier based on SiGe HBT technology, this detector was characterized at the H8 beam line at the CERN SPS. An excellent time resolution of (106 ± 1) ps for silicon detectors was measured with minimum ionizing particles.

  9. Reaching time resolution of less than 10 ps with plastic scintillation detectors

    NASA Astrophysics Data System (ADS)

    Zhao, J. W.; Sun, B. H.; Tanihata, I.; Terashima, S.; Zhu, L. H.; Enomoto, A.; Nagae, D.; Nishimura, T.; Omika, S.; Ozawa, A.; Takeuchi, Y.; Yamaguchi, T.

    2016-07-01

    Timing-pick up detectors with excellent timing resolutions are essential in many modern nuclear physics experiments. Aiming to develop a Time-Of-Flight system with precision down to about 10 ps, we have made a systematic study of the timing characteristic of TOF detectors, which consist of several combinations of plastic scintillators and photomultiplier tubes. With the conventional electronics, the best timing resolution of about 5.1 ps (σ) has been achieved for detectors with an area size of 3 × 1cm2 . It is found that for data digitalization a combination of TAC and ADC can achieve a better time resolution than the currently available TDC. Simultaneous measurements of both time and pulse height are very valuable for the correction of time-walk effect.

  10. A 2.9 ps equivalent resolution interpolating time counter based on multiple independent coding lines

    NASA Astrophysics Data System (ADS)

    Szplet, R.; Jachna, Z.; Kwiatkowski, P.; Rozyc, K.

    2013-03-01

    We present the design, operation and test results of a time counter that has an equivalent resolution of 2.9 ps, a measurement uncertainty at the level of 6 ps, and a measurement range of 10 s. The time counter has been implemented in a general-purpose reprogrammable device Spartan-6 (Xilinx). To obtain both high precision and wide measurement range the counting of periods of a reference clock is combined with a two-stage interpolation within a single period of the clock signal. The interpolation involves a four-phase clock in the first interpolation stage (FIS) and an equivalent coding line (ECL) in the second interpolation stage (SIS). The ECL is created as a compound of independent discrete time coding lines (TCL). The number of TCLs used to create the virtual ECL has an effect on its resolution. We tested ECLs made from up to 16 TCLs, but the idea may be extended to a larger number of lines. In the presented time counter the coarse resolution of the counting method equal to 2 ns (period of the 500 MHz reference clock) is firstly improved fourfold in the FIS and next even more than 400 times in the SIS. The proposed solution allows us to overcome the technological limitation in achievable resolution and improve the precision of conversion of integrated interpolators based on tapped delay lines.

  11. A time digitizer CMOS gate-array with a 250 ps time resolution

    SciTech Connect

    Arai, Yasuo

    1996-02-01

    Recent high-energy physics experiments are demanding a pipeline (deadtime-less) time-to-digital converter (TDC) with a time resolution of better than 500 ps and a double-pulse resolution of less than 30 ns. The TDC must keep all of the timing history until a trigger signal arrives about 3 {micro}s later. In large experiments, since the number of channels used is more than 100 k, the device must have a low power dissipation, a high circuit density and a low cost. A pipelined time digitizer CMOS gate-array has been developed using 0.5 {micro}m Sea-of-Gate technology. Precise timing signals which are used to sample input signals are generated from 32 taps of an asymmetric ring oscillator. The frequency of the oscillator is controlled by a phase-locked loop (PLL) circuit which runs in the 10--50 MHz frequency range. A test chip has been developed and tested; a time resolution of 250 ps rms at 40 MHz clock was measured. The chip has 4 channels and encoding circuits for both the rising and the falling edges of the input signals. The chip has 128-word dual-port memories, allowing the histories of the input signals to be stored and causing no deadtime for the conversion.

  12. Fast timing study of a CeBr3 crystal: Time resolution below 120 ps at 60Co energies

    NASA Astrophysics Data System (ADS)

    Fraile, L. M.; Mach, H.; Vedia, V.; Olaizola, B.; Paziy, V.; Picado, E.; Udías, J. M.

    2013-02-01

    We report on the time response of a novel inorganic scintillator, CeBr3. The measurements were performed using a cylindrical crystal of 1-in. in height and 1-in. in diameter at 22Na and 60Co photon energies. The time response was measured against a fast reference BaF2 detector. Hamamatsu R9779 and Photonis XP20D0 fast photomultipliers (PMTs) were used. The PMT bias voltages and Constant Fraction Discriminator settings were optimized with respect to the timing resolution. The Full Width at Half Maximum (FWHM) time resolution for an individual CeBr3 crystal coupled to Hamamatsu PMT is found here to be as low as 119 ps at 60Co energies, which is comparable to the resolution of 107 ps reported for LaBr3(Ce). For 511 keV photons the measured FWHM time resolution for CeBr3 coupled to the Hamamatsu PMT is 164 ps.

  13. A high resolution animal PET scanner using compact PS-PMT detectors

    SciTech Connect

    Watanabe, M.; Okada, H.; Shimizu, K.; Omura, T.

    1996-12-31

    A new high resolution PET scanner dedicated to animal studies has been designed, built and tested. The system utilizes 240 block detectors, each of which consists of a new compact position-sensitive photomultiplier tube (PS-PMT) and an 8 x 4 BGO array. A total number of 7,680 crystals (480 per ring) are positioned to form a 508 mm diameter of 16 detector rings with 7.2 mm pitch and 114 mm axial field of view (FOV). The system is designed to perform activation studies using a monkey in a sitting position. The data can be acquired in either 2D or 3D mode, where the slice collimators are retracted in 3D mode. The transaxial resolution is 2.6 mm FWHM at the center of the FOV, and the average axial resolution on the axis of the ring is 3.3 mm FWHM in the direct slice and 3.2 mm FWHM in the cross slice. The scatter fraction, sensitivity and count rate performance were evaluated for a 10 cm diameter cylindrical phantom. The total system sensitivity is 2.3 kcps/kBq/ml in 2D mode and 22.8 kcps/kBq/ml in 3D mode. The noise equivalent count rate with 3D mode is equivalent to that with 2D mode at five times higher radioactivity level. The applicable imaging capabilities of the scanner was demonstrated by animal studies with a monkey.

  14. Pulse-dilation enhanced gated optical imager with 5 ps resolution (invited)

    SciTech Connect

    Hilsabeck, T. J.; Kilkenny, J. D.; Hares, J. D.; Dymoke-Bradshaw, A. K. L.; Bell, P. M.; Koch, J. A.; Celliers, P. M.; Bradley, D. K.; McCarville, T.; Pivovaroff, M.; Soufli, R.; Bionta, R.

    2010-10-15

    A 5 ps gated framing camera was demonstrated using the pulse-dilation of a drifting electron signal. The pulse-dilation is achieved by accelerating a photoelectron derived information pulse with a time varying potential [R. D. Prosser, J. Phys. E 9, 57 (1976)]. The temporal dependence of the accelerating potential causes a birth time dependent axial velocity dispersion that spreads the pulse as it transits a drift region. The expanded pulse is then imaged with a conventional gated microchannel plate based framing camera and the effective gating time of the combined instrument is reduced over that of the framing camera alone. In the drift region, electron image defocusing in the transverse or image plane is prevented with a large axial magnetic field. Details of the unique issues associated with rf excited photocathodes were investigated numerically and a prototype instrument based on this principle was recently constructed. Temporal resolution of the instrument was measured with a frequency tripled femtosecond laser operating at 266 nm. The system demonstrated 20x temporal magnification and the results are presented here. X-ray image formation strategies and photometric calculations for inertial confinement fusion implosion experiments are also examined.

  15. 4 channel, 20 ps resolution, monolithic time-to-amplitude converter for multichannel TCSPC systems

    NASA Astrophysics Data System (ADS)

    Crotti, Matteo; Rech, Ivan; Labanca, Ivan; Ghioni, Massimo

    2012-06-01

    Over the past years an always growing interest has arisen about the measurement technique of time-correlated single photon counting (TCSPC) and many applications exploiting TCSPC have been developing in several fields, such as medicine and chemistry. The use of multianode PMTs and of single photon avalanche diode arrays led to the development of acquisition systems with several parallel channels, to employ the TCSPC technique in even more applications. Since TCSPC basically consists in the photons arrival time measurement, the most important part of an acquisition chain is the time measurement block, which must have high resolution and low differential nonlinearity and, in order to implement multidimensional systems, it has to be integrated to reduce both cost and area. To accomplish all these specifications, we have designed and fabricated a 4 channel fully integrated time-to-amplitude converter (TAC), built in 0.35 μm Si-Ge technology, characterized by a variable full scale range from 11 ns to 89 ns, very good time resolution (better than 20 ps FWHM), low differential nonlinearity (better than 0.04 LSB peak-peak and less than 0.2% LSB rms), high counting rate (16 MHz), low and constant power dissipation (50 mW) and low area occupation (340 × 390 μm2 per channel). Our measurements also show a very little crosstalk between converters integrated on the same chip; this feature together with low power and low area make the fabricated converter suitable for parallelization, so that it can be the starting point for future acquisition chains with a high number of parallel channels.

  16. X-ray bang-time and fusion reaction history at ~ps resolution using RadOptic detection

    SciTech Connect

    Vernon, S P; Lowry, M E; Baker, K L; Bennett, C V; Celeste, J R; Cerjan, C; Haynes, S; Hernandez, V J; Hsing, W W; London, R A; Moran, B; von Wittenau, A S; Steele, P T; Stewart, R E

    2012-05-01

    We report recent progress in the development of RadOptic detectors, radiation to optical converters, that rely upon x-ray absorption induced modulation of the optical refractive index of a semiconductor sensor medium to amplitude modulate an optical probe beam. The sensor temporal response is determined by the dynamics of the electron-hole pair creation and subsequent relaxation in the sensor medium. Response times of a few ps have been demonstrated in a series of experiments conducted at the LLNL Jupiter Laser Facility. This technology will enable x-ray bang-time and fusion burn-history measurements with {approx} ps resolution.

  17. The TDCpix readout ASIC: A 75 ps resolution timing front-end for the NA62 Gigatracker hybrid pixel detector

    NASA Astrophysics Data System (ADS)

    Kluge, A.; Aglieri Rinella, G.; Bonacini, S.; Jarron, P.; Kaplon, J.; Morel, M.; Noy, M.; Perktold, L.; Poltorak, K.

    2013-12-01

    The TDCpix is a novel pixel readout ASIC for the NA62 Gigatracker detector. NA62 is a new experiment being installed at the CERN Super Proton Synchrotron. Its Gigatracker detector shall provide on-beam tracking and time stamping of individual particles with a time resolution of 150 ps rms. It will consist of three tracking stations, each with one hybrid pixel sensor. The peak flow of particles crossing the detector modules reaches 1.27 MHz/mm2 for a total rate of about 0.75 GHz. Ten TDCpix chips will be bump-bonded to every silicon pixel sensor. Each chip shall perform time stamping of 100 M particle hits per second with a detection efficiency above 99% and a timing accuracy better than 200 ps rms for an overall three-station-setup time resolution of better than 150 ps. The TDCpix chip has been designed in a 130 nm CMOS technology. It will feature 45×40 square pixels of 300×300 μm2 and a complex End of Column peripheral region including an array of TDCs based on DLLs, four high speed serializers, a low-jitter PLL, readout and control circuits. This contribution will describe the complete design of the final TDCpix ASIC. It will discuss design choices, the challenges faced and some of the lessons learned. Furthermore, experimental results from the testing of circuit prototypes will be presented. These demonstrate the achievement of key performance figures such as a time resolution of the processing chain of 75 ps rms with a laser sent to the center of the pixel and the capability of time stamping charged particles with an overall resolution below 200 ps rms.

  18. Four-frame gated optical imager with 120-ps resolution (invited)

    SciTech Connect

    Young, P.E.; Hares, J.D.; Kilkenny, J.D.; Phillion, D.W.; Campbell, E.M.

    1988-08-01

    In this article we describe the operation and applications of a framing camera capable of four separate two-dimensional images with each frame having a 120-ps gate width. Fast gating of a single frame is accomplished by using a wafer image intensifier tube in which the cathode is capacitively coupled to an external electrode placed outside of the photocathode of the tube. This electrode is then pulsed relative to the microchannel plate by a narrow (120-ps), high-voltage pulse. Multiple frames are obtained by using multiple gated tubes which share a single bias supply and pulser with relative gate times selected by the cable lengths between the tubes and the pulser. A beam-splitter system has been constructed which produces a separate image for each tube from a single scene. Applications of the framing camera to inertial confinement fusion experiments are discussed.

  19. Sub-100 ps coincidence time resolution for positron emission tomography with LSO:Ce codoped with Ca.

    PubMed

    Nemallapudi, Mythra Varun; Gundacker, Stefan; Lecoq, Paul; Auffray, Etiennette; Ferri, Alessandro; Gola, Alberto; Piemonte, Claudio

    2015-06-21

    The coincidence time resolution (CTR) becomes a key parameter of 511 keV gamma detection in time of flight positron emission tomography (TOF-PET). This is because additional information obtained through timing leads to a better noise suppression and therefore a better signal to noise ratio in the reconstructed image. In this paper we present the results of CTR measurements on two different SiPM technologies from FBK coupled to LSO:Ce codoped 0.4%Ca crystals. We compare the measurements performed at two separate test setups, i.e. at CERN and at FBK, showing that the obtained results agree within a few percent. We achieve a best CTR value of 85 ± 4 ps FWHM for 2 × 2 × 3 mm(3) LSO:Ce codoped 0.4%Ca crystals, thus breaking the 100 ps barrier with scintillators similar to LSO:Ce or LYSO:Ce. We also demonstrate that a CTR of 140 ± 5 ps can be achieved for longer 2 × 2 × 20 mm(3) crystals, which can readily be implemented in the current generation PET systems to achieve the desired increase in the signal to noise ratio. PMID:26020610

  20. Time of flight positron emission tomography towards 100ps resolution with L(Y)SO: an experimental and theoretical analysis

    NASA Astrophysics Data System (ADS)

    Gundacker, S.; Auffray, E.; Frisch, B.; Jarron, P.; Knapitsch, A.; Meyer, T.; Pizzichemi, M.; Lecoq, P.

    2013-07-01

    Scintillation crystals have a wide range of applications in detectors for high energy and medical physics. They are recquired to have not only good energy resolution, but also excellent time resolution. In medical applications, L(Y)SO crystals are commonly used for time of flight positron emission tomography (TOF-PET). This study aims at determining the experimental and theoretical limits of timing using L(Y)SO based scintillators coupled to silicon photomultipliers (SiPMs). Measurements are based on the time-over-threshold method in a coincidence setup utilizing the ultra-fast amplifier-discriminator NINO and a fast oscilloscope. Using a 2 × 2 × 3 mm3 LSO:Ce codoped 0.4% Ca crystal coupled to a commercially available SiPM (Hamamatsu S10931-050P MPPC), we achieve a coincidence time resolution (CTR) of 108±5ps FWHM measured at E=511keV. We determine the influence of the data acquisition system to 27±2ps FWHM and thus negligible as compared to the CTR. This shows that L(Y)SO scintillators coupled to SiPM photodetectors are capable of achieving very good time resolution close to the desired 100ps FWHM for TOF-PET systems. To fully understand the measured values, we developed a simulation tool in MATLAB that incorporates the timing properties of the photodetector, the scintillation properties of the crystal and the light transfer within the crystal simulated by SLITRANI. The simulations are compared with measured data in order to determine their predictive power. Finally we use this model to discuss the influence of several important parameters on the time resolution like scintillation rise- and fall time and light yield, as well as single photon time resolution (SPTR) and the detection efficiency of the SiPM. In addition we find the influence of photon travel time spread in the crystal not negligible on the CTR, even for the used 2 × 2 × 3 mm3 geometry.

  1. Resolution limitations and optimization of the ITT F4157 streak tube focus for fast (10 ps) operation

    SciTech Connect

    Lerche, R.A.; Grasz, E.L.; Griffith, R.L.; Simpson, R.A.; Posey, R.

    1987-11-01

    The ITT F4157 image tube is biased at voltages far from the original design for operation in an ultrafast (10 ps) streak camera. Its output resolution at streak camera operating potentials has been measured as a function of input slit width, incident-light wavelength, and focus-grid voltage. The results are similar to those reported for the RCA C73435 streak tube. Indeed, the two tubes can be substituted for each other with minor mechanical modifications. The temporal resolution is insensitive to focus-grid voltage for a narrow (50 ..mu..m) input slit, but is very sensitive to focus-grid voltage for a wide (500 ..mu..m) input slit. Spatial resolution is nearly independent of focus-grid voltage for values that give good temporal resolution. Both temporal and spatial resolution depend on the incident-light wavelength. Streak camera operation is simulated with a computer program that calculates photoelectron trajectories. Electron ray tracing describes the observed effects of slit width, incident-light wavelength, and focus-grid voltage on the output resolution. 6 refs., 10 figs., 1 tab.

  2. The TDCpix Readout ASIC: A 75 ps Resolution Timing Front-End for the Gigatrackerof theNA62 Experiment

    NASA Astrophysics Data System (ADS)

    Rinella, G. Aglieri; Fiorini, M.; Jarron, P.; Kaplon, J.; Kluge, A.; Martin, E.; Morel, M.; Noy, M.; Perktold, L.; Poltorak, K.

    NA62 is an experiment under development at the CERN Super Proton Synchrotron, aiming at measuring ultra rare kaon decays. The Gigatracker (GTK) detector shall combine on-beam tracking of individual particles with a time resolution of 150 ps rms. The peak flow of particles crossing the detector modules reaches 1.27 MHz/mm2 fora total rateof about 0.75 GHz.Ahybrid siliconpixel detectoris beingdevelopedto meet these requirements. The pixel chip for the Gigatracker (TDCpix) is under design. The TDCpix chip will feature 1800 square pixels of 300×300 μm2 arranged in a matrix of 45 rows × 40 columns. Bump-bonded to a silicon pixel sensor it shall perform time stamping of particle hits with a timing accuracybetter than 200 ps rms and a detection efficiencyabove 99%. The chosen architecture provides full separation of the sensitive analog amplifiers of the pixel matrix from the noisy digital circuits of the TDCs and of the readout blocks. Discriminated hit signals from each pixel are transmitted to the end of column region. An array ofTime to Digital Converters (TDC) is implemented at the bottom of the pixel array. The TDCs are based on time tagging the events with the fine time codes generated by Delay Locked Loops (DLL) and have a nominal time bin of ˜100 ps. Time stamps and time-over-threshold are recorded for each discriminated hit and the correction of the discriminator's time-walk is performed off-detector. Data are continuously transmitted on four 2.4 Gb/s serial output links. Adescription of the on-going design of the final TDCpix is given in this paper. Design choices and some technical implementation details are presented. Aprototype ASIC including thekeycomponents of this architecture has been manufactured. The achievement of specification figures such as a time resolution of the processing chain of 75 ps rms as well as charged particle time stampingwitha resolutionbetterthan200psrmswere demonstratedexperimentally.Asummaryoftheseresultsisalso presented in

  3. Self-assembly of high-resolutions PS-b-PMMA block-copolymers: processes capabilities and integration on 300mm track

    NASA Astrophysics Data System (ADS)

    Chevalier, X.; Nicolet, C.; Tiron, R.; Gharbi, A.; Chamiot-Maitral, G.; Jullian, K.; Pimenta-Barros, P.; Argoud, M.; Peyre, J.-L.; Van Spaandonk, R.; Fleury, G.; Hadziioannou, G.; Navarro, C.

    2014-03-01

    Careful control and reproducibility of BCP's synthesis are mandatory parameters to push-down PS-b-PMMA block-copolymer systems toward its lowest dimensions for microelectronic applications. The self-assembly process optimization of different high-resolution cylindrical PS-b-PMMA block-copolymers (i.e. L0 period below 25 nm) is studied to highlight processes-variations as regard to more classical PS-b-PMMA systems while the characterizations of bulk materials provide deeper insights on the parameters addressing the self-assembly of such materials. The integration of a high-resolution BCP on 300 mm track is then studied to check the capabilities of such materials in terms of lithographic applications. CD uniformity measurements in contact hole shrink approach, as well as the transfer of the BCP mask into typical industrial under-layer stacks leading to aggressive features, show that these materials exhibit promising potentials for advanced lithographic nodes.

  4. Sub-100ps single photoelectron time resolution of a strip silicon photomultiplier for time-resolved optical spectroscopy

    NASA Astrophysics Data System (ADS)

    Wang, Shenyuan; Liu, Rongdan; Liang, Kun; Yang, Ru; Han, Dejun

    2015-10-01

    SiPM with epitaxial quenching resistors developed at NDL (Novel Device Laboratory, Beijing) could alleviate the conflict between large dynamic range and high photon detection efficiency (PDE). It can be used as low light level detector in various applications with excellent single photoelectron time resolution (SPTR) and photon counting capacity. SPTR is mainly determined by the intrinsic structure parameters of the SiPM. However, it is also limited to measurement setup, electronics readout and the ultra-small signal of single photoelectron level. In this work, we designed and fabricated a 1 mm × 1 mm strip SiPM array for possible applications in time-resolved optical spectroscopy. The SiPM array consists of sixteen 50 μm × 1 mm strip SiPM elements. Each element contains five hundred 6.5 μm × 6.5 μm micro avalanche photodiode (APD) cells with 10μm pitch. The strip SiPM demonstrated SPTR of 68 ps (FWHM), peak PDE of 17% around 450 nm and high photon number resolving and photon counting capability.

  5. Particle Identification Using Cost Effective mRPC Technology for Time-of-Flight Measurements with Less than 10 ps Time Resolution

    NASA Astrophysics Data System (ADS)

    Shimek, Taylor

    2015-10-01

    This presentation will introduce the use of multi-gap Resistive Plate Chambers (mRPCs) for time of flight (TOF) based particle identification (PID) in nuclear and high-energy physics. The mRPC technology is developed for use in future experiments at the planned Electron Ion Collider, EIC. TOF PID using mRPCs with 10 ps timing resolution will make it possible to precisely determine the flavor content of valence- and sea-quarks in the proton through semi-inclusive deep inelastic scattering with identified pions and kaons. A first mRPC prototype using float glass resistive plates at UIUC has reached a timing resolution of 21 ps. In this presentation I discuss an effort to replace the float glass with cheaper Mylar-based resistive plates. I will also discuss the design and construction of a first prototype and present initial results on signal development, efficiencies and timing resolution of the mRPC prototype.

  6. Resolution and shutter speed measurements of an MCPII with a 270-ps whole image shutter for a point-source input

    SciTech Connect

    Thomas, M.C.; Yates, G.J.; Zagarino, P.

    1995-07-01

    The modulation transfer function (MF) of a shuttered, 18-mm-diameter, proximity-focused microchemical-plate image intensifier (MCPII) was measured as a function of time in the shutter sequence. Electrical gate pulses were delivered to the MCPII with microstrip impedance transformers for reduced pulse dispersion and reflections. Using 30 ps FWHM, 600 nm pulses from a sync-pumped dye, argon-ion laser as a probe, the MCPII`s shutter speed for point-source (6-{mu}m-diameter) illumination and 230 ps FWHM, {minus}590 V gate pulses was measured to be between 200 and 250 ps FWHM. The MF of the MCPII was measured by analyzing the point spread function (PSF) for inputs at several different locations on the MCPII and at different times in the shuttering sequence. The best 50% MF resolution of 16.2 lp/mm was found with illumination near the edge where the gate pulse enters the MCPII and at 120 ps into the shutter sequence. The whole image (18-mm-diameter) shutter speed (off-to-off) of the MCPII was measured to be 270 ps.

  7. Design and assessment of a 6 ps-resolution time-to-digital converter with 5 MGy gamma-dose tolerance for nuclear instrumentation

    SciTech Connect

    Cao, Y.; Leroux, P.; De Cock, W.; Steyaert, M.

    2011-07-01

    Time-to-Digital Converters (TDCs) are key building blocks in time-based mixed-signal systems, used for the digitization of analog signals in time domain. A short survey on state-of-the-art TDCs is given. In order to realize a TDC with picosecond time resolution as well as multi MGy gamma-dose radiation tolerance, a novel multi-stage noise-shaping (MASH) delta-sigma ({Delta}{Sigma}) TDC structure is proposed. The converter, implemented in 0.13 {mu}m, achieves a time resolution of 5.6 ps and an ENOB of 11 bits, when the over sampling ratio (OSR) is 250. The TDC core consumes only 1.7 mW, and occupies an area of 0.11 mm{sup 2}. Owing to the usage of circuit level radiation hardened-by-design techniques, such as passive RC oscillators and constant-g{sub m} biasing, the TDC exhibits enhanced radiation tolerance. At a low dose rate of 1.2 kGy/h, the frequency of the counting clock in the TDC remains constant up to at least 160 kGy. Even after a total dose of 3.4 MGy at a high dose rate of 30 kGy/h, the TDC still achieves a time resolution of 10.5 ps with an OSR of 250. (authors)

  8. A single shot TDC with 4.8 ps resolution in 40 nm CMOS for high energy physics applications

    NASA Astrophysics Data System (ADS)

    Prinzie, J.; Steyaert, M.; Leroux, P.

    2015-01-01

    A robust TDC with 4.8 ps bin width has been designed for harsh environments and high energy physics applications. The circuit uses resistive interpolation DLL with a novel dual phase detector architecture. This architecture improves startup- and recovery speed from single event strikes without control voltage ripple trade-off and requires no off-line calibrations. A 0.43 LSB DNL has been measured at a power consumption of 4.2 mW with an extended frequency range from 0.8 GHz to 2.4 GHz. The TDC has been processed in 40 nm CMOS technology.

  9. Detection of high energy muons with sub-20 ps timing resolution using L(Y)SO crystals and SiPM readout

    NASA Astrophysics Data System (ADS)

    Benaglia, A.; Gundacker, S.; Lecoq, P.; Lucchini, M. T.; Para, A.; Pauwels, K.; Auffray, E.

    2016-09-01

    Precise timing capability will be a key aspect of particle detectors at future high energy colliders, as the time information can help in the reconstruction of physics events at the high collision rate expected there. Other than being used in detectors for PET, fast scintillating crystals coupled to compact Silicon Photomultipliers (SiPMs) constitute a versatile system that can be exploited to realize an ad-hoc timing device to be hosted in a larger high energy physics detector. In this paper, we present the timing performance of LYSO:Ce and LSO:Ce codoped 0.4% Ca crystals coupled to SiPMs, as measured with 150 GeV muons at the CERN SPS H2 extraction line. Small crystals, with lengths ranging from 5 mm up to 30 mm and transverse size of 2 × 2mm2 or 3 × 3mm2 , were exposed to a 150 GeV muon beam. SiPMs from two different companies (Hamamatsu and FBK) were used to detect the light produced in the crystals. The best coincidence time resolution value of (14.5 ± 0.5) ps , corresponding to a single-detector time resolution of about 10 ps, is demonstrated for 5 mm long LSO:Ce,Ca crystals coupled to FBK SiPMs, when time walk corrections are applied.

  10. A 75 ps rms time resolution BiCMOS time to digital converter optimized for high rate imaging detectors

    NASA Astrophysics Data System (ADS)

    Hervé, C.; Torki, K.

    2002-04-01

    This paper presents an integrated time to digital converter (TDC) with a bin size adjustable in the range of 125 to 175 ps and a differential nonlinearity of ±0.3%. The TDC has four channels. Its architecture has been optimized for the readout of imaging detectors in use at Synchrotron Radiation facilities. In particular, a built-in logic flags piled-up events. Multi-hit patterns are also supported for other applications. Time measurements are extracted off chip at the maximum throughput of 40 MHz. The dynamic range is 14 bits. It has been fabricated in 0.8 μm BiCMOS technology. Time critical inputs are PECL compatible whereas other signals are CMOS compatible. A second application specific integrated circuit (ASIC) has been developed which translates NIM electrical levels to PECL ones. Both circuits are used to assemble board level TDCs complying with industry standards like VME, NIM and PCI.

  11. Modeling the Nucleus Laminaris of the Barn Owl: Achieving 20 ps Resolution on a 85-MHz-Clocked Digital Device.

    PubMed

    Salomon, Ralf; Heinrich, Enrico; Joost, Ralf

    2012-01-01

    The nucleus laminaris of the barn owl auditory system is quite impressive, since its underlying time estimation is much better than the processing speed of the involved neurons. Since precise localization is also very important in many technical applications, this paper explores to what extent the main principles of the nucleus laminaris can be implemented in digital hardware. The first prototypical implementation yields a time resolution of about 20 ps, even though the chosen standard, low-cost device is clocked at only 85 MHz, which leads to an internal duty cycle of approximately 12 ns. In addition, this paper also explores the utility of an advanced sampling scheme, known as unfolding-in-time. It turns out that with this sampling method, the prototype can easily process input signals of up to 300 MHz, which is almost four times higher than the sampling rate. PMID:22347179

  12. Modeling the Nucleus Laminaris of the Barn Owl: Achieving 20 ps Resolution on a 85-MHz-Clocked Digital Device

    PubMed Central

    Salomon, Ralf; Heinrich, Enrico; Joost, Ralf

    2012-01-01

    The nucleus laminaris of the barn owl auditory system is quite impressive, since its underlying time estimation is much better than the processing speed of the involved neurons. Since precise localization is also very important in many technical applications, this paper explores to what extent the main principles of the nucleus laminaris can be implemented in digital hardware. The first prototypical implementation yields a time resolution of about 20 ps, even though the chosen standard, low-cost device is clocked at only 85 MHz, which leads to an internal duty cycle of approximately 12 ns. In addition, this paper also explores the utility of an advanced sampling scheme, known as unfolding-in-time. It turns out that with this sampling method, the prototype can easily process input signals of up to 300 MHz, which is almost four times higher than the sampling rate. PMID:22347179

  13. A photoelectron-photoion coincidence imaging apparatus for femtosecond time-resolved molecular dynamics with electron time-of-flight resolution of {sigma}=18 ps and energy resolution {delta}E/E=3.5%

    SciTech Connect

    Vredenborg, Arno; Roeterdink, Wim G.; Janssen, Maurice H. M.

    2008-06-15

    We report on the construction and performance of a novel photoelectron-photoion coincidence machine in our laboratory in Amsterdam to measure the full three-dimensional momentum distribution of correlated electrons and ions in femtosecond time-resolved molecular beam experiments. We implemented sets of open electron and ion lenses to time stretch and velocity map the charged particles. Time switched voltages are operated on the particle lenses to enable optimal electric field strengths for velocity map focusing conditions of electrons and ions separately. The position and time sensitive detectors employ microchannel plates (MCPs) in front of delay line detectors. A special effort was made to obtain the time-of-flight (TOF) of the electrons at high temporal resolution using small pore (5 {mu}m) MCPs and implementing fast timing electronics. We measured the TOF distribution of the electrons under our typical coincidence field strengths with a temporal resolution down to {sigma}=18 ps. We observed that our electron coincidence detector has a timing resolution better than {sigma}=16 ps, which is mainly determined by the residual transit time spread of the MCPs. The typical electron energy resolution appears to be nearly laser bandwidth limited with a relative resolution of {delta}E{sub FWHM}/E=3.5% for electrons with kinetic energy near 2 eV. The mass resolution of the ion detector for ions measured in coincidence with electrons is about {delta}m{sub FWHM}/m=1/4150. The velocity map focusing of our extended source volume of particles, due to the overlap of the molecular beam with the laser beams, results in a parent ion spot on our detector focused down to {sigma}=115 {mu}m.

  14. Observation and Analysis of Strong Oscillating Electric Fields in a ps and fs Laser Plasma by High-resolution X-ray Spectroscopy Measurements

    SciTech Connect

    Faenov, A. Ya.; Pikuz, T. A.; Skobelev, I. Yu.; Magunov, A. I.; Belyaev, V. S.; Vinogradov, V. I.; Matafonov, A. P.; Lisitsa, V. S.; Gavrilenko, V. P.; Pikuz, S. A. Jr.; Kim, K. Y.; Milchberg, H. M.

    2006-04-07

    The results of measurements of the multicharged ions spectra in plasma produced by moderately intense (up to 4x1017 W/cm-2) laser pulses are presented. In the first case, Nd glass laser radiation with energy 1 - 2 J and pulse duration 1.5 ps was focused on the flat solid Teflon target. In the second case, Ti:Sa laser radiation with energy {approx}70 mJ and pulse duration 70 and 500 fs was focused onto an N2O gas jet, created by a high-pressure liquid nitrogen cooled, pulsed (10 Hz) nozzle. Profiles of the Ly{alpha} lines of F IX ions in Teflon target and O VIII ions in N2O clusters were recorded with a very high spectral resolution {lambda}/{delta}{lambda} {approx} 3000 - 5000. The features (peaks and dips) in the Ly{alpha} line profiles were observed. They suggest the existence of intense plasma oscillations with a frequency appreciably lower than the frequency of the laser radiation. The observed X-ray spectra for the plasma satellites of the Ly{alpha} doublet of the hydrogen F IX and O VIII ions in plasma were modeled theoretically. It was shown that the resulting doublet profile have a complex structure, which depends nontrivially both on the plasma temperature, density and on the frequency and amplitude of the plasma oscillations. Experimental positions of the satellites and their separations allowed them to be associated with intense electrostatic oscillations with an amplitude E0 {approx} (4-6)x108 Vcm-1 and a frequency {omega} {approx} (0.7-1)x1015 s-1 for F IX ions and E0 {approx} (0.5 - 1.0)x10 9 V/cm and frequency {omega} {approx} (0.7-2.4)x1015 s-1 for O VIII, simultaneously. Assuming the oscillation frequency to be determined by the strength of the magnetic field B generated in the plasma, we obtained an estimate of B that is in reasonable agreement with other measurements.

  15. 10 ps resolution, 160 ns full scale range and less than 1.5% differential non-linearity time-to-digital converter module for high performance timing measurements.

    PubMed

    Markovic, B; Tamborini, D; Villa, F; Tisa, S; Tosi, A; Zappa, F

    2012-07-01

    We present a compact high performance time-to-digital converter (TDC) module that provides 10 ps timing resolution, 160 ns dynamic range and a differential non-linearity better than 1.5% LSB(rms). The TDC can be operated either as a general-purpose time-interval measurement device, when receiving external START and STOP pulses, or in photon-timing mode, when employing the on-chip SPAD (single photon avalanche diode) detector for detecting photons and time-tagging them. The instrument precision is 15 ps(rms) (i.e., 36 ps(FWHM)) and in photon timing mode it is still better than 70 ps(FWHM). The USB link to the remote PC allows the easy setting of measurement parameters, the fast download of acquired data, and their visualization and storing via an user-friendly software interface. The module proves to be the best candidate for a wide variety of applications such as: fluorescence lifetime imaging, time-of-flight ranging measurements, time-resolved positron emission tomography, single-molecule spectroscopy, fluorescence correlation spectroscopy, diffuse optical tomography, optical time-domain reflectometry, quantum optics, etc. PMID:22852708

  16. 10 ps resolution, 160 ns full scale range and less than 1.5% differential non-linearity time-to-digital converter module for high performance timing measurements

    SciTech Connect

    Markovic, B.; Tamborini, D.; Villa, F.; Tisa, S.; Tosi, A.; Zappa, F.

    2012-07-15

    We present a compact high performance time-to-digital converter (TDC) module that provides 10 ps timing resolution, 160 ns dynamic range and a differential non-linearity better than 1.5% LSB{sub rms}. The TDC can be operated either as a general-purpose time-interval measurement device, when receiving external START and STOP pulses, or in photon-timing mode, when employing the on-chip SPAD (single photon avalanche diode) detector for detecting photons and time-tagging them. The instrument precision is 15 ps{sub rms} (i.e., 36 ps{sub FWHM}) and in photon timing mode it is still better than 70 ps{sub FWHM}. The USB link to the remote PC allows the easy setting of measurement parameters, the fast download of acquired data, and their visualization and storing via an user-friendly software interface. The module proves to be the best candidate for a wide variety of applications such as: fluorescence lifetime imaging, time-of-flight ranging measurements, time-resolved positron emission tomography, single-molecule spectroscopy, fluorescence correlation spectroscopy, diffuse optical tomography, optical time-domain reflectometry, quantum optics, etc.

  17. 10 ps resolution, 160 ns full scale range and less than 1.5% differential non-linearity time-to-digital converter module for high performance timing measurements

    NASA Astrophysics Data System (ADS)

    Markovic, B.; Tamborini, D.; Villa, F.; Tisa, S.; Tosi, A.; Zappa, F.

    2012-07-01

    We present a compact high performance time-to-digital converter (TDC) module that provides 10 ps timing resolution, 160 ns dynamic range and a differential non-linearity better than 1.5% LSBrms. The TDC can be operated either as a general-purpose time-interval measurement device, when receiving external START and STOP pulses, or in photon-timing mode, when employing the on-chip SPAD (single photon avalanche diode) detector for detecting photons and time-tagging them. The instrument precision is 15 psrms (i.e., 36 psFWHM) and in photon timing mode it is still better than 70 psFWHM. The USB link to the remote PC allows the easy setting of measurement parameters, the fast download of acquired data, and their visualization and storing via an user-friendly software interface. The module proves to be the best candidate for a wide variety of applications such as: fluorescence lifetime imaging, time-of-flight ranging measurements, time-resolved positron emission tomography, single-molecule spectroscopy, fluorescence correlation spectroscopy, diffuse optical tomography, optical time-domain reflectometry, quantum optics, etc.

  18. High-tech breakthrough DNA scanner for reading sequence and detecting gene mutation: A powerful 1 lb, 20 {mu}m resolution, 16-bit personal scanner (PS) that scans 17inch x 14inch x-ray film in 48 s, with laser, uv and white light sources

    SciTech Connect

    Zeineh, J.A.; Zeineh, M.M.; Zeineh, R.A.

    1993-06-01

    The 17inch x 14inch X-ray film, gels, and blots are widely used in DNA research. However, DNA laser scanners are costly and unaffordable for the majority of surveyed biotech scientists who need it. The high-tech breakthrough analytical personal scanner (PS) presented in this report is an inexpensive 1 lb hand-held scanner priced at 2-4% of the bulky and costly 30-95 lb conventional laser scanners. This PS scanner is affordable from an operation budget and biotechnologists, who originate most science breakthroughs, can acquire it to enhance their speed, accuracy, and productivity. Compared to conventional laser scanners that are currently available only through hard-to-get capital-equipment budgets, the new PS scanner offers improved spatial resolution of 20 {mu}m, higher speed (scan up to 17inch x 14inch molecular X-ray film in 48 s), 1-32,768 gray levels (16-bits), student routines, versatility, and, most important, affordability. Its programs image the film, read DNA sequences automatically, and detect gene mutation. In parallel to the wide laboratory use of PC computers instead of mainframes, this PS scanner might become an integral part of a PC-PS powerful and cost-effective system where the PS performs the digital imaging and the PC acts on the data.

  19. The PS1 Observatory

    NASA Astrophysics Data System (ADS)

    Kaiser, Nick; Morgan, J.; Pier, E.; Chambers, K.

    2007-12-01

    The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) will use gigapixel cameras on multi-aperture telescopes to survey the sky in the visible and near-infrared bands. The first surveys will begin in 2008 using a single telescope system (PS1) has been deployed on Haleakala, Maui. This facility is currently undergoing commissioning tests. The PS1 telescope is a 1.8-m f/4 Richey-Chretien design that employs three 50 cm diameter correcting lens. The optical system produces a 3 degree diameter field of view at the focal plane. Images will be recorded on a 1.4 gigapixel CCD camera (described in an accompanying poster presentation). The survey programs will be conducted using g, r, i, and z filters which closely approximate the band-pass and response of those used in the Sloan Digital Sky Survey. These filters will be supplemented with a y band filter further to the infrared of z and a wide w filter for solar system observations. The images from the PS1 camera are supplemented by an Imaging Sky Probe that will provide co-pointed photometric calibration images of each target field. An all-sky camera at the observatory monitors sky conditions and transparency. The operation of the PS1 telescope is supported by the Observatory, Telescope, and Instrument Software (OTIS) system. The OTIS software interfaces the telescope control software provided by the vendor and the CCD camera computer systems. OTIS also records and archives environmental metadata from the dome and the observatory weather station.

  20. Accelerating PS model-based dynamic cardiac MRI using compressed sensing.

    PubMed

    Zhang, Xiaoyong; Xie, Guoxi; Shi, Caiyun; Su, Shi; Zhang, Yongqin; Liu, Xin; Qiu, Bensheng

    2016-02-01

    High spatiotemporal resolution MRI is a challenging topic in dynamic MRI field. Partial separability (PS) model has been successfully applied to dynamic cardiac MRI by exploiting data redundancy. However, the model requires substantial preprocessing data to accurately estimate the model parameters before image reconstruction. Since compressed sensing (CS) is a potential technique to accelerate MRI by reducing the number of acquired data, the combination of PS and CS, named as Stepped-SparsePS, was introduced to accelerate the preprocessing data acquisition of PS in this work. The proposed Stepped-SparsePS method sequentially reconstructs a set of aliased dynamic images in each channel based on PS model and then the final dynamic images from the aliased images using CS. The results from numerical simulations and in vivo experiments demonstrate that Stepped-SparsePS could significantly reduce data acquisition time while preserving high spatiotemporal resolution. PMID:26552006

  1. The PS1 Software Systems

    NASA Astrophysics Data System (ADS)

    Heasley, James N.; Jedicke, R.; Magnier, E.

    2007-12-01

    The Pan-STARRS PS1 observatory will generate on average 1.4 TBytes of image data during a typical night of observing. To support the reduction and analysis of these data, the Pan-STARRS construction project has developed three software systems: the Image Processing Pipeline (IPP) for the reduction and calibration of the images and the generation of source catalogs, the Moving Object Processing System (MOPS), a science client designed to develop orbital information for the moving transient sources found by the IPP, and the Published Science Products Subsystem (PSPS) which will serve as the scientific access point to the catalog data derived by the IPP and as the overall archive for the science products generated by PS1. The IPP has largely been developed internally at the Institute for Astronomy. The software has been extensively tested on CCD mosaic data from the CFH12K, MegaPrime, and Suprime cameras. Since late August 2007 we have been using IPP to process the first images from the PS1 gigapixel camera. MOPS incorporates both legacy code and new software developed for linking observations of objects on different nights into tracklets for orbit determination. The MOPS has been tested with simulations based on our model of the solar system as well as on data from the SpaceWatch observatory. The primary component of the PSPS is the Object Data Manager (ODM) which will serve as the science database for the stationary objects found in the PS1 observations. We anticipate tracking over 5.5 billion objects and 140 billion detections over the 3.5 year mission of PS1. The ODM is leveraging the design work done during the Sloan Digital Sky Survey to scale out a database design to accommodate this volume of data.

  2. MUW Approach of PS OCT

    NASA Astrophysics Data System (ADS)

    Hitzenberger, Christoph K.; Pircher, Michael

    Polarization sensitive (PS) OCT is a functional extension of OCT that exploits the light's polarization state to generate intrinsic, tissue specific contrast and enables quantitative measurements of tissue parameters. This chapter explains the technique, discusses polarization-changing light-tissue interactions and demonstrates the application of PS-OCT to retinal imaging. Two polarization-changing light-tissue interactions are discussed and their use for retinal diagnostics are demonstrated: (i) birefringence, which is found in fibrous tissues like the retinal nerve fiber layer and can be used for glaucoma diagnostics; and (ii) depolarization, which is observed in the retinal pigment epithelium (RPE) and can be used to segment the RPE and associated lesions like drusen or geographic atrophies in age related macular degeneration.

  3. Image enhancement using a range gated MCPII video system with a 180-ps FWHM shutter

    SciTech Connect

    Thomas, M.C.; Yates, G.J.; Zadgarino, P.

    1995-09-01

    The video image of a target submerged in a scattering medium was improved through the use of range gating techniques. The target, an Air Force resolution chart, was submerged in 18 in. of a colloidal suspension of tincture green soap in water. The target was illuminated with pulsed light from a Raman shifted, frequency-doubled, ND:YAG laser having a wavelength of 559 mm and a width of 20 ps FWHM. The laser light reflected by the target along with the light scattered by the soap, was imaged onto a microchannel-plate image intensifier (MCPII). The output from the MCPII was then recorded with a RS-170 video camera and a video digitizer. The MCPII was gated on with a pulse synchronously timed to the laser pulse. The relative timing between the reflected laser pulse and the shuttering of the MCPII determined the distance to the imaged region. The resolution of the image was influenced by the MCPII`s shutter time. A comparison was made between the resolution of images obtained with 6 ns, 500 ps and 180 ps FWHM (8 ns, 750 ps and 250 ps off-to-off) shutter times. it was found that the image resolution was enhanced by using the faster shutter since the longer exposures allowed light scattered by the water to be recorded too. The presence of scattered light in the image increased the noise, thereby reducing the contrast and the resolution.

  4. PP/PS anisotropic stereotomography

    NASA Astrophysics Data System (ADS)

    Nag, Steinar; Alerini, Mathias; Ursin, Bjørn

    2010-04-01

    Stereotomography is a slope tomographic method which gives good results for background velocity model estimation in 2-D isotropic media. We develop here the extension of the method to 3-D general anisotropic media for PP and PS events. We do not take into account the issue of shear wave degeneracy. As in isotropic media, the sensitivity matrix of the inversion can be computed by paraxial ray tracing. We introduce a `constant Z stereotomography' approach, which can reduce the size of the sensitivity matrix. Based on ray perturbation theory, we give all the derivatives of stereotomography data parameters with respect to model parameters in a 3-D general anisotropic medium. These general formulas for the derivatives can also be used in other applications that rely on anisotropic ray perturbation theory. In particular, we obtain derivatives of the phase velocity with respect to position, phase angle and elastic medium parameters, all for general anisotropic media. The derivatives are expressed using the Voigt notation for the elastic medium parameters. We include a Jacobian that allows to change the model parametrization from Voigt to Thomsen parameters. Explicit expressions for the derivatives of the data are given for the case of 2-D tilted transversely isotropic (TTI) media. We validate the method by single-parameter estimation of each Thomsen parameter field of a 2-D TTI synthetic model, where data are modelled by ray tracing. For each Thomsen parameter, the estimated velocity field fits well with the true velocity field.

  5. P.S. 49: A Special Place.

    ERIC Educational Resources Information Center

    McEwen, Christian

    1991-01-01

    Describes the Teachers and Writers Collaborative at P.S 49 and the principal who keeps the writing program going. Discusses how the collaboration works and the teaching techniques used by the writing teachers in the school. (MG)

  6. Drosophila PS1 integrin is a laminin receptor and differs in ligand specificity from PS2.

    PubMed Central

    Gotwals, P J; Fessler, L I; Wehrli, M; Hynes, R O

    1994-01-01

    We have expressed Drosophila position-specific (PS) integrins on the surfaces of Schneider S2 cells and tested for adhesion and spreading on various matrix molecules. We report that PS1 integrin is a laminin receptor and that PS1 and PS2 integrins promote cell spreading on two different Drosophila extracellular matrix molecules, laminin and tiggrin, respectively. The differing ligand specificities of these two integrins, combined with data on the in vivo expression patterns of the integrins and their ligands, lead to a model for the structure of integrin-dependent attachments in the pupal wings and embryonic muscles of Drosophila. Images PMID:7972082

  7. Self-assembly of CdSe quantum dots and colloidal titanium dioxide on copolymer microspheres (PS) for CdSe/PS and TiO2/CdSe/PS sub-microspheres with yolk-shell structure

    NASA Astrophysics Data System (ADS)

    Zhao, Qingchun

    2015-07-01

    Semiconductor nanocrystals serve as the building blocks for designing next generation solar cells, chemical/biological sensors, and metal chalcogenides (e.g., CdS, CdSe, PbS, and PbSe) are particularly useful for harnessing size-dependent optical and electronic properties in nanostructures. In this paper, relying on the interaction including van der Waals forces and hydrogen bond, CdSe/PS sub-microspheres composite and TiO2/CdSe/PS sub-microspheres with yolk-shell structure were prepared via self-assembly of CdSe quantum dots and colloidal titanium dioxide on modified PS surface. The morphology, structure and composition obtained products were investigated by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and energy disperse X-ray spectroscopy (EDX). Transmission electron microscopy (TEM) investigations show the CdSe quantum dots and colloidal titanate were assembled on the surface of PS sub-microspheres. CdSe QD-polymer sub-microspheres composites in which the QDs retain their original emission efficiency can be obtained. TiO2/CdSe/PS sub-microspheres with yolk-shell structure can improve the efficiency of charge separation.

  8. Asiago spectroscopic classification of PS15cwx and PS15cwo

    NASA Astrophysics Data System (ADS)

    Tartaglia, L.; Pastorello, A.; Benetti, S.; Cappellaro, E.; Elias-Rosa, N.; Ochner, P.; Terreran, G.; Tomasella, L.; Turatto, M.

    2015-11-01

    The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic classifications of PS15cwx in 2MFGC 04279 and PS15cwo in SDSS J031116.60+011124.3 The targets were supplied by the Pan-STARRS Survey for Transients (see Huber et al., ATel #7153).

  9. CRTS observations of recent PS1 transients

    NASA Astrophysics Data System (ADS)

    Drake, A. J.; Mahabal, A. A.; Djorgovski, S. G.; Graham, M. J.; Williams, R.; Prieto, J.; Catelan, M.; Christensen, E.; Beshore, E. C.; Larson, S. M.

    2010-08-01

    Valenti et al. (2010, ATel#2773) recently reported the discovery of an AGN outburst (PS1-1000382) detected in PS1 taken data on June 12.23 UT with magnitude g=17.9. The redshift of the AGN is given by Valenti et al. (2010) as z=0.435 and host galaxy SDSS J160414.08+091354.0. We have extracted the five year archival CSS/CRTS lightcurve at the location of PS1-1000382 and SDSS DR7 data.

  10. Positron Annihilation in the Bipositronium Ps2

    SciTech Connect

    Bailey, David H.; Frolov, Alexei M.

    2005-07-01

    The electron-positron-pair annihilation in the bipositronium PS2 is considered. In particular, the two-, three-, one- and zero-photon annihilation rates are determined to high accuracy. The corresponding analytical expressions are also presented. Also, a large number of bound state properties have been determined for this system.

  11. The 4 Ps as a Guiding Perspective

    ERIC Educational Resources Information Center

    Kalsbeek, David H.

    2013-01-01

    A 4 Ps perspective addresses immediate needs: to help institutions gain traction in their retention strategies by framing and reframing the challenges and the possible responses, by challenging some of the traditional mental models about retention that can distract or dilute those strategies, and by offering focus and coherence to institutional…

  12. Asiago spectroscopic classification of PS15cyk

    NASA Astrophysics Data System (ADS)

    Tartaglia, L.; Pastorello, A.; Benetti, S.; Cappellaro, E.; Elias-Rosa, N.; Ochner, P.; Terreran, G.; Tomasella, L.; Turatto, M.

    2015-12-01

    The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic classification of PS15cyk in UGC 12687. The target is supplied by the Pan-STARRS Survey for Transients (see Huber et al., ATel #7153).

  13. 10th Anniversary P.S.

    ScienceCinema

    None

    2011-04-25

    John Adams parle de la préhistoire du P.S. avec présentation des dias. Le DG B.Gregory prend la parole. Les organisateurs présentent sous la direction du "Prof.Ocktette"(?) un sketch très humoristique (p.e.existence de Quark etc.....)

  14. A 7.5 ps single-shot precision integrated time counter with segmented delay line

    NASA Astrophysics Data System (ADS)

    Klepacki, K.; Szplet, R.; Pelka, R.

    2014-03-01

    This paper describes the design and test results of time interval counter featuring the single-shot precision of 7.5 ps root mean square (rms) and measurement range of 1 ms. These parameters have been achieved by combining direct counting method with a two-stage interpolation within a single clock period. Both stages of interpolation are based on the use of tapped delay lines stabilized by delay locked loop mechanism. In the first stage, a coarse resolution is obtained with the aid of high frequency multiphase clock, while in the second stage a sub-gate delay resolution is achieved with the use of differential delay line. To reduce the nonlinearities of conversion and to improve the precision of measurement, a novel segmented delay line is proposed. An important feature of this segmented delay line is partial overlapping of measurement range and resulting enhancement of both resolution and precision of time interval counter. The maximum integral nonlinearity error of the fine-stage interpolators does not exceed 16 ps and 14 ps in START and STOP interpolators, respectively. These errors have been identified by statistical calibration procedure and corrected to achieve single-shot precision better than 7.5 ps (rms). The time counter is integrated in a single ASIC (Application Specific Integrated Circuit) chip using a standard cost-effective 0.35 μm CMOS (Complementary Metal Oxide Semiconductor) process.

  15. The Study of Interpenetration Length between dPS Films and PS-grafted Layers

    NASA Astrophysics Data System (ADS)

    Lee, Hoyeon; Jo, Seongjun; Hirata, Toyoaki; Yamada, Norifumi L.; Tanaka, Keiji; Ryu, Du Yeol

    In polymer thin film system, the type of interfacial interaction is a critical parameter to determining the thermal and physical properties of polymer films. Interestingly, the interfacial energy of grafted substrates with polymer chains is remarkably altered by simply controlling grafting density, which has been referred to as autophobicity. In this study, we investigated the interpenetrating interfaces between deuterated polystyrene (dPS) and grafted substrates with the same chemical identity. PS-grafted substrates were prepared using a grafting-to approach with hydroxyl end-functionalized polystyrene (PSOH) in a dry brush regime, where the brush thickness and grafting density were determined based on the chain length (or molecular weight, Mn) of PSOHs. The interpenetration lengths (ξ) at interfaces between dPS and PS-grafted layers were characterized using neutron reflectivity (NR) measurements (performed at the SOFIA beam-line at J-PARC, Japan). Academic adviser.

  16. Sub-10ps monolithic and low-power photodetector readout

    SciTech Connect

    Varner, Gary S.; Ruckman, Larry L.

    2009-02-20

    Recent advances in photon detectors have resulted in high-density imaging arrays that offer many performance and cost advantages. In particular, the excellent transit time spread of certain devices show promise to provide tangible benefits in applications such as Positron Emission Tomography (PET). Meanwhile, high-density, high-performance readout techniques have not kept on pace for exploiting these developments. Photodetector readout for next generation high event rate particle identification and time-resolved PET requires a highly-integrated, low-power, and cost-effective readout technique. We propose fast waveform sampling as a method that meets these criteria and demonstrate that sub-10ps resolution can be obtained for an existing device.

  17. High speed, high strength microwelding of Si/glass using ps-laser pulses.

    PubMed

    Miyamoto, Isamu; Okamoto, Yasuhiro; Hansen, Assi; Vihinen, Joma; Amberla, Tiina; Kangastupa, Jarno

    2015-02-01

    A novel microwelding procedure to join Si-to-glass using ps-laser pulses with high repetition rates is presented. The procedure provides weld joint with mechanical strength as high as 85 MPa and 45 MPa in sample pairs of Si/aluminosilicate (Si/SW-Y) and Si/borosilicate (Si/Borofloat 33), respectively, which are higher than anodic bonding, at high spatial resolution (< 20 µm) and very high throughput without pre- and post-heating. Laser-matter interaction analysis indicates that excellent weld joint of Si/glass is obtained by avoiding violent evaporation of Si substrate using ps-laser pulses. Laser welded Si/glass samples can be singulated along the weld lines by standard blade dicer without defects, demonstrating welding by ps-laser pulses is applicable to wafer-level packaging. PMID:25836199

  18. OCT/PS-OCT imaging of brachial plexus neurovascular structures

    NASA Astrophysics Data System (ADS)

    Raphael, David T.; Zhang, Jun; Zhang, Yaoping; Chen, Zhongping; Miller, Carol; Zhou, Li

    2004-07-01

    Introduction: Optical coherence tomography (OCT) allows high-resolution imaging (less than 10 microns) of tissue structures. A pilot study with OCT and polarization-sensitive OCT (PS-OCT) was undertaken to image ex-vivo neurovascular structures (vessels, nerves) of the canine brachial plexus. Methods: OCT is an interferometry-based optical analog of B-mode ultrasound, which can image through non-transparent biological tissues. With approval of the USC Animal Care and Use Committee, segments of the supra- and infraclavicular brachial plexus were excised from euthanized adult dogs, and the ex-vivo specimens were placed in cold pH-buffered physiologic solution. An OCT beam, in micrometer translational steps, scanned the fixed-position bisected specimens in transverse and longitudinal views. Two-dimensional images were obtained from identified arteries and nerves, with specific sections of interest stained with hematoxylin-eosin for later imaging through a surgical microscope. Results: with the beam scan direction transverse to arteries, the resulting OCT images showed an identifiable arterial lumen and arterial wall tissue layers. By comparison, transverse beam OCT images of nerves revealed a multitude of smaller nerve bundles contained within larger circular-shaped fascicles. PS-OCT imaging was helpful in showing the characteristic birefringence exhibited by arrayed neural structures. Discussion: High-resolution OCT imaging may be useful in the optical identification of neurovascular structures during attempted regional nerve blockade. If incorporated into a needle-shaped catheter endoscope, such a technology could prevent intraneural and intravascular injections immediately prior to local anesthetic injection. The major limitation of OCT is that it can form a coherent image of tissue structures only to a depth of 1.5 - 2 mm.

  19. The new CERN PS timing system

    NASA Astrophysics Data System (ADS)

    Lewis, Julian; Sikolenko, Vitali

    1994-12-01

    The PS complex consists of nine interacting accelerators, which can produce from cycle to cycle beams varying in end user, particle type, energy, time structure and beam-geometry. Since the introduction of the new timing system, the sequencing of the PS accelerators now depends dynamically on their status, so that sequence changes in real-time are now produced automatically. This greatly improves the response time for changing end user requests and simplifies the task of the machine operators who no longer need to program it manually. Coordinating this intricate time-sharing particle factory is the MTG (Master Timing Generator) which broadcasts messages around the complex containing summary information on what each part must do next, and the timing needed to carry it out. These messages are received by Tg8 VME timing modules which then provide nearby equipment with timing pulses and the VME host processors with task synchronization events and summary information.

  20. Assessment of coronary plaque collagen with polarization sensitive optical coherence tomography (PS-OCT)

    NASA Astrophysics Data System (ADS)

    Giattina, Susanne D.; Courtney, Brian K.; Herz, Paul R.; Harman, Michelle; Shortkroff, Sonya; Stamper, Debra L.; Liu, Bin; Fujimoto, James G.; Brezinski, Mark E.

    2006-02-01

    Current evidence indicates that most plaques classified as vulnerable or ruptured plaques do not lead to unstable angina or myocardial infarction. Improved methods are needed to risk stratify plaques to identify those which lead to most acute coronary syndromes. Collagen depletion in the intima overlying lipid collections appears to be a critical component of unstable plaques. In this study, we use polarization sensitive optical coherence tomography (PS-OCT) for the assessment of coronary plaque collagen. Collagen is birefringent, meaning that different polarization states travel through it at different velocities. Changes in PS-OCT images are a measure of tissue birefringence. Twenty-two coronary artery segments were imaged with PS-OCT and analyzed by picrosirius staining (a measure of collagen intensity and fiber size) and trichrome blue. The regression plot between PS-OCT changes and measured collagen yielded a correlation coefficient value of 0.475 (p<0.002). Good correlation was noted between two blinded investigators both with respect to PS-OCT measurements as well as luminosity as assessed by picrosirius. The predictive value of a PS-OCT measurement of negligible birefringence (less than 33% change) for minimal collagen was 93% while the predictive value of high birefringence (greater than 66% change) for high collagen concentrations was 89%. The effect of fiber type (chemical composition) was minimal relative to the effect due to fiber concentration. The capability of PS-OCT to assess plaque collagen content, in addition to its ability to generate high resolution structural assessments, make it a potentially powerful technology for identifying high risk plaques.

  1. Regeneration of tumor antigen-specific CTLs utilizing iPS technology.

    PubMed

    Maeda, Takuya; Masuda, Kyoko; Kawamoto, Hiroshi

    2016-08-01

    Tumor immunotherapy, especially tumor antigen specific T cell therapy, is currently attracting attention. However, a critical issue still awaits resolution; it is difficult to efficiently expand tumor antigen-specific T cells. To solve this problem, we are now utilizing iPS cell technology. When iPS cells are established from tumor antigen specific T cells, T cells regenerated from these iPS cells are expected to express the same TCRs as the original T cells. In line with this concept, we succeeded in regenerating tumor antigen specific cytotoxic T cells. The regenerated T cells exhibited TCR specific killing activity comparable to that of the original cells, and were able to kill leukemia cells in an antigen-specific manner. We are currently endeavoring to apply this method clinically. In the future, we intend to establish an allogeneic transfusion system, in which various tumor antigen specific T-iPS cells from a wide range of HLA haplotype homozygous donors will be lined up as a "T-iPS cell bank", with the aim of making off-the-shelf tumor immunotherapy a reality. PMID:27599425

  2. Comparison of Cyberware PX and PS 3D human head scanners

    NASA Astrophysics Data System (ADS)

    Carson, Jeremy; Corner, Brian D.; Crockett, Eric; Li, Peng; Paquette, Steven

    2008-02-01

    A common limitation of laser line three-Dimensional (3D) scanners is the inability to scan objects with surfaces that are either parallel to the laser line or that self-occlude. Filling in missing areas adds some unwanted inaccuracy to the 3D model. Capturing the human head with a Cyberware PS Head Scanner is an example of obtaining a model where the incomplete areas are difficult to fill accurately. The PS scanner uses a single vertical laser line to illuminate the head and is unable to capture data at top of the head, where the line of sight is tangent to the surface, and under the chin, an area occluded by the chin when the subject looks straight forward. The Cyberware PX Scanner was developed to obtain this missing 3D head data. The PX scanner uses two cameras offset at different angles to provide a more detailed head scan that captures surfaces missed by the PS scanner. The PX scanner cameras also use new technology to obtain color maps that are of higher resolution than the PS Scanner. The two scanners were compared in terms of amount of surface captured (surface area and volume) and the quality of head measurements when compared to direct measurements obtained through standard anthropometry methods. Relative to the PS scanner, the PX head scans were more complete and provided the full set of head measurements, but actual measurement values, when available from both scanners, were about the same.

  3. Spectroscopic Classification of PS16ccj with Mayall/KOSMOS

    NASA Astrophysics Data System (ADS)

    Pan, Y.-C.; Foley, R. J.; Jha, S. W.; Rest, A.; Scolnic, D.

    2016-05-01

    We report the classification of PS16ccj from spectroscopic observation with KOSMOS on the Mayall telescope. The observation was made on 2016 May 05 UT. We classify PS16ccj as a SN Ia near maximum light.

  4. PS-analysis of InSAR data stacks through a quick and simple approach

    NASA Astrophysics Data System (ADS)

    Riva, D.; D'Aria, D.; Monti Guarnieri, A.; Giudici, D.; Scagliola, M.

    2012-12-01

    PS InSAR is a very useful remote-sensing technique for detecting and monitoring line-of-sight (uplift and subsidence) surface deformations both in rural zones and urbanized area. In this paper, an accurate PS analysis technique is described. This technique leads to the estimate of the PS differential velocity, phase and displacement starting from a SAR interferometric dataset. PS differential velocity can be useful to analyze the deformation of chosen sites in order to detect unexpected terrain movements and identify hazard risks in particular in urbanized areas. The technique is an original implementation of the Persistent Scatterers analysis, based on the correction of the atmospheric disturbance through the estimation of a differential velocity field to be integrated and removed from the original interferograms. This core step is important as it allows to obtain the atmospheric corrected phases while avoiding the direct estimation of the phase itself. The procedure exploits the initial set of PS candidates to estimate the spatial gradient of the phase and, after this step, the differential velocity field. Being this field estimated on the spatial gradient of the phases, it is smooth and can be unwrapped leading to a straight velocity analysis. The atmospheric phase screen (APS) is interpolated over all the pixels, allowing the densification of the PS set in a second iteration. The APS can be useful to enhance tomographic studies in chosen areas, reducing errors introduced in the InSAR data stacks by atmospheric disturbance. Knowing the location of each PS, its velocity and tomographic information, dynamic 3D city models can be generated. The proposed approach allows to analyze SAR interferometric datasets belonging to sensors with different resolutions. In this paper the result of processing COSMO SKYMED high resolution Stripmap data (about 3 x 3 meters resolution) provided by the Politecnico of Milan in the frame of the ASI-AO #1080 "SAR data Calibration and

  5. PAN/PS elctrospun fibers for oil spill cleanup

    NASA Astrophysics Data System (ADS)

    Ying, Qiao; Lili, Zhao; Haixiang, Sun; Peng, Li

    2014-08-01

    A high-capacity oil sorbent was fabricated by electrospinning using PS/PAN blend. Morphology, contact angle and oil adsorption of PAN/PS fiber and PP nonwoven fabric were studied. It was found that the PAN/PS fiber had a smaller diameter than PP, and the maximum sorption capacities of the PAN/PS sorbent for pump oil, peanut oil, diesel, and gasoline were 194.85, 131.7, 66.75, and 43.38 g/g, which were far higher than those of PP. The sorbent PS/PAN fiber showed a contact angle of water144.32° and diesel oil 0°. The sorption kinetics of PAN/PS and PP sorbent were also investigated. Compared with the commercial PP fabric, the PAN/PS fiber seems to have the ability to be used in oil-spill cleanup application.

  6. Internal gastargets in AmPS

    NASA Astrophysics Data System (ADS)

    Kaan, A. P.; Postma, O.; van den Brand, J. F. J.; van Leeuwen, E.; Doets, M.; Kraan, M.

    1997-05-01

    Internal gas targets in AmPS A.P. Kaan, O. Postma, J.F.J. van den Brand, E. van Leeuwen, M. Doets, M. Kra= an National Institute for Nuclear Physics and High Energy Physics; Kruislaan 409; 1098 SJ Amsterdam; Holland In the Amsterdam Puls Stretcher/storage ring AmPS(1 GeV electrons), we designed a set-up in order to accommodate a gas target with a density of 1016 mol/cm2. The storage cell needed for this purpose is a aluminium tube with a length of 40 cm, a diameter of 15 mm and a wall thickness of 25 =B5m. Three sets of conductance limiters on both sides of the target, combined with dry turbopumps are designed to be used as differential pumping stations. These limiters cause discontinuities in the beam path and must therefor be retractable and radio frequency compatible in both positions. Low =B5 materials must be used because of the depolarisation effects of changing magnetic fields. The calculations show that the flow resistance's are sufficient to reduce the load of the getter pumps to a level with which the lifetime of the pump elements remain acceptable. The design of the mechanics and the vacuum system will be explained. Recent results from the measurements after installation in combination with the influence on the lifetime on the beam will be presented

  7. PS2004 Light-harvesting Systems Workshop

    SciTech Connect

    Robert E. Blankenship

    2005-11-01

    This special issue of the international scientific research journal Photosynthesis Research consists of 25 original peer-reviewed contributions from participants in the PS 2004 Lisht-Harvesting Systems Workshop. This workshop was held from 26-29, 2004 at Hotel Le Chantecler, Sainte-Adele, Quebec, Canada. The workshop was a satellite meeting of the XIII International Congress on Photosynthesis held August 29-September 3, 2004 in Montreal, Canada. The workshope dealt with all types of photosynthetic antenna systems and types of organisms, including anoxygenic photosynthetic bacteria, cyanobacteria, algae and higher plants, as well as in vitro studies of isolated pigments. This collection of papers is a good representation of the highly interdisciplinary nature of modern research on photosynthetic antenna complexes, utilizing techniques of advanced spectroscopy, biochemistry, molecular biology, synthetic chemistry and structural determination to understand these diverse and elegant molecular complexes.

  8. Findings in Ps-H scattering

    SciTech Connect

    Ray, Hasi

    2006-06-15

    The best three-channel projectile-inelastic close-coupling approximation (CCA) is used to study the resonances in positronium (Ps) and hydrogen (H) scattering at the energy region below the inelastic threshold. The s-wave elastic phase shifts and s-wave elastic cross sections are studied using the static-exchange, two- and three-channel projectile-inelastic CCA for both the singlet (+) and triplet (-) channels. The singlet resonances detected using different CCA schemes confirm previous predictions [Drachman and Houston, Phys. Rev. A 12, 885 (1975); Page, J. Phys. B. 9, 1111 (1976)]. We report a resonance in the triplet channel too using the present three-channel CCA scheme.

  9. Spectroscopic Classification of AT2016axw (=MASTER OT J142718.40-014031.0 =PS16axi)

    NASA Astrophysics Data System (ADS)

    Blanchard, Peter; Berger, Edo; Bieryla, Allyson; Brzycki, Bryan; Cohn, Amy; Dillett, Sean; Feder-Staehle, Richard; Frostig, Danielle; Grell, Gabe; James, Nicholas; Johnson, April; Mahmood, Zahra; Merryman, Hunter; Peak, Barra; Sanders, Cecilia; Taylor, Anthony

    2016-03-01

    We obtained a low-resolution optical spectrum of AT2016axw (=MASTER OT J142718.40-014031.0 =PS16ayd; ATel #8791). Observations were carried out on 2016 March 16.4 UT using the FAST spectrograph mounted on the F.L. Whipple Observatory 1.5-m telescope.

  10. Directed self-assembly of PS-b-PMMA with ionic liquid addition

    NASA Astrophysics Data System (ADS)

    Chen, Xuanxuan; Seo, Takehito; Rincon-Delgadillo, Paulina; Matsumiya, Tasuku; Kawaue, Akiya; Maehashi, Takaya; Gronheid, Roel; Nealey, Paul F.

    2016-03-01

    Directed self-assembly of block copolymers is a promising candidate to address grand challenges towards new generations of low-cost, high-resolution nanopatterning technology. Over the past decade, poly(styrene-b-methyl methacrylate) (PS-b-PMMA) has been the most popular block copolymer applied in this area. However, further scaling towards pitches below 20 nm is hindered by its relatively low segregation strength between constituent blocks, characterized by a low Flory-Huggins interaction parameter, χ (~ 0.038 at r.t). To reach sub-10 nm feature dimensions, many high- χ block copolymer materials and processes are currently being studied. Here we investigate the DSA of PSb- PMMA with blended ionic liquid (IL) on chemically-patterned substrates via thermal annealing with a free surface. In this materials system, by adding low volume fraction of IL, a substantially higher χ than the pure block copolymer is achieved with manageable change in surface and interfacial properties so that poly(styrene-random-methyl methacrylate) brushes may be used to control substrate wetting behavior, and the blend could be assembled using thermal annealing with a free surface. In other words, PS-b-PMMA/IL may serve as a high- χ drop-in replacement for PS-b-PMMA. In this work, we provide key DSA results to determine if PS-b-PMMA/IL blends would offer a solution for sub-10 nm lithography.

  11. Photoinactivation of PS2 secondary donors by PS2 cation radicals and superoxide radicals

    SciTech Connect

    Chen, G.X.; Cheniae, G.M.; Blubaugh, D.J.; Golbeck, J.H.

    1991-12-31

    Illumination of Mn- and Cl-depleted PS2 causes rapid irreversible inactivation of specific redox-active components on the donor side of the PS2 Reaction Center (RC). Under aerobic conditions, weak light preillumination of NH{sub 2}OH-PS2 causes rapid loss of Y{sub Z}{sup {plus_minus}} formation, Y{sub Z} {yields} P{sub 680}{sup +}, the A{sub T}-band thermoluminescence emission, the Y{sub Z}{sup +}-dependent (Site 1) photooxidation of exogenous e{sup {minus}} donors, and the capability to photoligate Mn{sup 2+} into the water oxidizing enzyme (photoactivation), all without significantly affecting P{sub 680}{sup +}/Q{sub A}{sup {minus}} charge separation. In contrast, aerobic high light preillumination of Mn-depleted PS2 promotes very rapid and parallel loss of photoactivation and A{sub T}-band emission capabilities significantly than loss of either Y{sub Z}{sup +}-formation or P{sub 680}{sup +}/Q{sub A}{sup {minus}} charge separation capabilities. These photodamages and those to Cl-depleted thylakoids (4,5) generally are believed to be caused by reactions between the highly oxidizing cation radicals (P{sub 680}{sup +}/Chl{sup +}) and nearby amino acid residues of D{sub 1}>D{sub 2}. The reported promotion of the photodamages by e{sup {minus}} acceptors of Q{sub A}{sup {minus}}/Q{sub B}{sup {minus}} their inhibition by e{sup {minus}} donors to Y{sub Z}{sup +} and their occurrence under strict anaerobic conditions all tend to support the idea of direct damage by P{sub 680}{sup +}/Chl{sup +}. Our studies lead us to conclude that the photodamages to the donor side components are caused minimally by a rapid mechanism requiring both superoxide and PS2 cation radicals; and by a slower mechanism driven by the PS2 cation radicals only.

  12. Energy and expectation values of the PsH system

    SciTech Connect

    Mitroy, J.

    2006-05-15

    Close to converged energies and expectation values for PsH are computed using a ground state wave function consisting of 1800 explicitly correlated gaussians. The best estimate of the Ps{sup {infinity}}H energy was -0.789 196 740 hartree which is the lowest variational energy to date. The 2{gamma} annihilation rate for Ps{sup {infinity}}H was 2.471 78x10{sup 9} s{sup -1}.

  13. PS: A nonprocedural language with data types and modules

    NASA Technical Reports Server (NTRS)

    Gokhale, M. B.

    1986-01-01

    The Problem Specification (PS) nonprocedural language is a very high level language for algorithm specification. PS is suitable for nonprogrammers, who can specify a problem using mathematically-oriented equations; for expert programmers, who can prototype different versions of a software system for evaluation; and for those who wish to use specifications for portions (if not all) of a program. PS has data types and modules similar to Modula-2. The compiler generates C code. PS is first shown by example, and then efficiency issues in scheduling and code generation are discussed.

  14. Lysophosphatidylserine analogues differentially activate three LysoPS receptors.

    PubMed

    Uwamizu, Akiharu; Inoue, Asuka; Suzuki, Kensuke; Okudaira, Michiyo; Shuto, Akira; Shinjo, Yuji; Ishiguro, Jun; Makide, Kumiko; Ikubo, Masaya; Nakamura, Sho; Jung, Sejin; Sayama, Misa; Otani, Yuko; Ohwada, Tomohiko; Aoki, Junken

    2015-03-01

    Lysophosphatidylserine (1-oleoyl-2 R-lysophosphatidylserine, LysoPS) has been shown to have lipid mediator-like actions such as stimulation of mast cell degranulation and suppression of T lymphocyte proliferation, although the mechanisms of LysoPS actions have been elusive. Recently, three G protein-coupled receptors (LPS1/GPR34, LPS2/P2Y10 and LPS3/GPR174) were found to react specifically with LysoPS, raising the possibility that LysoPS serves as a lipid mediator that exerts its role through these receptors. Previously, we chemically synthesized a number of LysoPS analogues and evaluated them as agonists for mast-cell degranulation. Here, we used a transforming growth factor-α (TGFα) shedding assay to see if these LysoPS analogues activated the three LysoPS receptors. Modification of the serine moiety significantly reduced the ability of the analogues to activate the three LysoPS receptors, whereas modification of other parts resulted in loss of activity in receptor-specific manner. We found that introduction of methyl group to serine moiety (1-oleoyl-lysophosphatidylallothreonine) and removal of sn-2 hydroxyl group (1-oleoyl-2-deoxy-LysoPS) resulted in reduction of reactivity with LPS1 and LPS3, respectively. Accordingly, we synthesized a LysoPS analogue with the two modifications (1-oleoyl-2-deoxy-lysophosphatidylallothreonine) and found it to be an LPS2-selective agonist. These pharmacological tools will definitely help to identify the biological roles of these LysoPS receptors. PMID:25320102

  15. The HARP detector at the CERN PS

    NASA Astrophysics Data System (ADS)

    Catanesi, M. G.; Muciaccia, M. T.; Radicioni, E.; Simone, S.; Edgecock, R.; Ellis, M.; Robbins, S.; Soler, F. J. P.; Gößling, C.; Mass, M.; Bunyatov, S.; Chukanov, A.; Klimov, O.; Krasin, I.; Krasnoperov, A.; Kustov, D.; Popov, B.; Serdiouk, V.; Tereshchenko, V.; Carassiti, V.; Di Capua, E.; Evangelisti, F.; Vidal-Sitjes, G.; Artamonov, A.; Arce, P.; Brocard, R.; Decreuse, G.; Friend, B.; Giani, S.; Gilardoni, S.; Gorbunov, P.; Grant, A.; Grossheim, A.; Gruber, P.; Ivanchenko, V.; Legrand, J.-C.; Kayis-Topaksu, A.; Panman, J.; Papadopoulos, I.; Pasternak, J.; Tcherniaev, E.; Tsukerman, I.; van der Vlugt, R.; Veenhof, R.; Wiebusch, C.; Zucchelli, P.; Blondel, A.; Borghi, S.; Campanelli, M.; Cervera-Villanueva, A.; Morone, M. C.; Prior, G.; Schroeter, R.; Kato, I.; Gastaldi, U.; Mills, G. B.; Graulich, J. S.; Grégoire, G.; Bonesini, M.; Chignoli, F.; Ferri, F.; Paleari, F.; Kirsanov, M.; Postoev, V.; Bagulya, A.; Grichine, V.; Polukhina, N.; Palladino, V.; Coney, L.; Schmitz, D.; Barr, G.; De Santo, A.; Pattison, C.; Zuber, K.; Barichello, G.; Bobisut, F.; Gibin, D.; Guglielmi, A.; Laveder, M.; Menegolli, A.; Mezzetto, M.; Pepato, A.; Dumarchez, J.; Troquereau, S.; Vannucci, F.; Dore, U.; Iaciofano, A.; Lobello, M.; Marinilli, F.; Orestano, D.; Panayotov, D.; Pasquali, M.; Pastore, F.; Tonazzo, A.; Tortora, L.; Booth, C.; Buttar, C.; Hodgson, P.; Howlett, L.; Nicholson, R.; Bogomilov, M.; Burin, K.; Chizhov, M.; Kolev, D.; Petev, P.; Rusinov, I.; Tsenov, R.; Piperov, S.; Temnikov, P.; Apollonio, M.; Chimenti, P.; Giannini, G.; Santin, G.; Burguet-Castell, J.; Gómez-Cadenas, J. J.; Novella, P.; Sorel, M.; Tornero, A.

    2007-02-01

    HARP is a high-statistics, large solid angle experiment to measure hadron production using proton and pion beams with momenta between 1.5 and 15 GeV/ c impinging on many different solid and liquid targets from low to high Z. The experiment, located in the T9 beam of the CERN PS, took data in 2001 and 2002. For the measurement of momenta of produced particles and for the identification of particle types, the experiment includes a large-angle spectrometer, based on a Time Projection Chamber and a system of Resistive Plate Chambers, and a forward spectrometer equipped with a set of large drift chambers, a threshold Cherenkov detector, a time-of-flight wall and an electromagnetic calorimeter. The large angle system uses a solenoidal magnet, while the forward spectrometer is based on a dipole magnet. Redundancy in particle identification has been sought, to enable the cross-calibration of efficiencies and to obtain a few percent overall accuracy in the cross-section measurements. Detector construction, operation and initial physics performances are reported. In addition, the full chain for data recording and analysis, from trigger to the software framework, is described.

  16. Modulation of enzymatic PS synthesis by liposome membrane composition.

    PubMed

    Pinsolle, Alexandre; Roy, Philippe; Cansell, Maud

    2014-03-01

    Phosphatidylserine (PS) is a phospholipid known to exert important physiological roles in humans. However, this phospholipid (PL) is poorly available as a natural source and hardly produced by the chemical route. In this work, PS was obtained by transphosphatidylation using phospholipase D (PLD) and PL self-assembled into liposomes as the substrates. The aim was to better understand how the liposome membrane composition could modulate PS yield. Three lecithins were used as PL substrates, one originated from a marine source providing a high amount of n-3 polyunsaturated fatty acids, and two issued from soya differing in their phosphatidylcholine (PC) content. Different parameters such as Ca(2+) content, enzyme and L-serine concentrations modulated PS synthesis. The presence of Ca(2+) increased PS conversion yield. The alcohol acceptor (L-serine) concentration positively acted on PL conversion, by governing the equilibrium between transphosphatidylation and hydrolysis. Beside these specific reaction conditions, it was demonstrated that the membrane composition of the liposomes modulated PS synthesis. A direct correlation between PS accumulation and the amount of cholesterol or α-tocopherol incorporated into the soya lecithins was observed. This result was interpreted in terms of "head" spacers promoting PLD transphosphatidylation. On the whole, this work provided key parameters for the formulation of liposomes using enzymatic PLD technology, to produce lecithins enriched in different proportions of PS and esterified with various types of fatty acids depending on the initial lecithin source. PMID:24334268

  17. Pan-STARRS PS1 Published Science Products Subsystem

    NASA Astrophysics Data System (ADS)

    Heasley, J.; Smith, W.; Eek, R.; Rosen, J.

    This paper describes the requirements and design of the Pan-STARRS PS1 Published Science Products Subsystem (PSPS) that constitutes the primary distribution tool for the very large amount of science data products produced by the Pan-STARRS PS1 prototype telescope. The data management challenges are identified in terms of stressing characteristics: dynamic, fast, spatial, and large; these are countered by mitigating characteristics: simple and lenient. This combination of characteristics is not only distinctly more demanding than traditional survey astronomy data managers, but lies at the boundaries of current commercially available data management technology. The requirements imposed on the PSPS result in devising a design strategy at the boundaries of currently available data management technology. In particular, we describe the capabilities and characteristics of the four main PS1 PSPS components: the Web-Based Interface (WBI), the Data Retrieval Layer (DRL), the Object Data Manager (ODM), and the Solar System Data Manager (SSDM). Potential architectural strategies are examined in the context of the stressing and mitigating characteristics with the conclusion that the ODM should follow an architectural concept that emphasizes the pooling of application, processing, and storage resources. The PS1 PSPS is specifically designed to support the PS1 science mission (see K.C. Chambers et al., these proceedings) while at the same time providing substantial design direction for a future PSPS component of the final PS4 Pan-STARRS. Finally, the limitations and possible scalability of the PS1 design relative to PS4 are discussed.

  18. Spectroscopic Classification of PS16chs with SOAR/Goodman

    NASA Astrophysics Data System (ADS)

    Miller, J. A.; Hounsell, R. A.; Pan, Y.-C.; Foley, R. J.; Jha, S. W.; Rest, A.; Scolnic, D.

    2016-05-01

    We report the classification of PS16chs from spectroscopic observation with the Goodman spectrograph on the SOAR telescope. The observation was made on 2016 May 08 UT. We classify PS16chs as a SN Ia near maximum light at z = 0.19.

  19. Safeguarding Nonhuman Primate iPS Cells With Suicide Genes

    PubMed Central

    Zhong, Bonan; Watts, Korashon L; Gori, Jennifer L; Wohlfahrt, Martin E; Enssle, Joerg; Adair, Jennifer E; Kiem, Hans-Peter

    2011-01-01

    The development of technology to generate induced pluripotent stem (iPS) cells constitutes one of the most exciting scientific breakthroughs because of the enormous potential for regenerative medicine. However, the safety of iPS cell-related products is a major concern for clinical translation. Insertional mutagenesis, possible oncogenic transformation of iPS cells or their derivatives, or the contamination of differentiated iPS cells with undifferentiated cells, resulting in the formation of teratomas, have remained considerable obstacles. Here, we demonstrate the utility of suicide genes to safeguard iPS cells and their derivatives. We found suicide genes can control the cell fate of iPS cells in vitro and in vivo without interfering with their pluripotency and self-renewal capacity. This study will be useful to evaluate the safety of iPS cell technology in a clinically highly relevant, large animal model and further benefit the clinical use of human iPS cells. PMID:21587213

  20. Beam optics of the AmPS extraction line

    NASA Astrophysics Data System (ADS)

    Hoekstra, R.

    1991-01-01

    The beam optics of the AmPS (Amsterdam Pulse Stretcher) are described. Definitions are outlined, and the beam elements and parameters are given. Developments relating to the electrostatic septum, chicane, beam transformer and bending through 90 degrees are described. The performance of the AmPS and beam diagnostics are discussed.

  1. Final results for π± production in the HARP/PS214 experiment at CERN PS

    NASA Astrophysics Data System (ADS)

    Bonesini, M.; HARP/PS214 Collaboration

    2012-08-01

    The final results on π± production in proton nucleus or π± nucleus interactions for incident particle momenta between 1.5 GeV/c and 15 GeV/c as measured in the HARP/PS214 experiment at CERN PS are presented.

  2. Solution structure of the PsIAA4 oligomerization domain reveals interaction modes for transcription factors in early auxin response.

    PubMed

    Dinesh, Dhurvas Chandrasekaran; Kovermann, Michael; Gopalswamy, Mohanraj; Hellmuth, Antje; Calderón Villalobos, Luz Irina A; Lilie, Hauke; Balbach, Jochen; Abel, Steffen

    2015-05-12

    The plant hormone auxin activates primary response genes by facilitating proteolytic removal of auxin/indole-3-acetic acid (AUX/IAA)-inducible repressors, which directly bind to transcriptional auxin response factors (ARF). Most AUX/IAA and ARF proteins share highly conserved C-termini mediating homotypic and heterotypic interactions within and between both protein families. The high-resolution NMR structure of C-terminal domains III and IV of the AUX/IAA protein PsIAA4 from pea (Pisum sativum) revealed a globular ubiquitin-like β-grasp fold with homologies to the Phox and Bem1p (PB1) domain. The PB1 domain of wild-type PsIAA4 features two distinct surface patches of oppositely charged amino acid residues, mediating front-to-back multimerization via electrostatic interactions. Mutations of conserved basic or acidic residues on either face suppressed PsIAA4 PB1 homo-oligomerization in vitro and confirmed directional interaction of full-length PsIAA4 in vivo (yeast two-hybrid system). Mixing of oppositely mutated PsIAA4 PB1 monomers enabled NMR mapping of the negatively charged interface of the reconstituted PsIAA4 PB1 homodimer variant, whose stoichiometry (1:1) and equilibrium binding constant (KD ∼ 6.4 μM) were determined by isothermal titration calorimetry. In silico protein-protein docking studies based on NMR and yeast interaction data derived a model of the PsIAA4 PB1 homodimer, which is comparable with other PB1 domain dimers, but indicated considerable differences between the homodimeric interfaces of AUX/IAA and ARF PB1 domains. Our study provides an impetus for elucidating the molecular determinants that confer specificity to complex protein-protein interaction circuits between members of the two central families of transcription factors important to the regulation of auxin-responsive gene expression. PMID:25918389

  3. Demonstration of 11-ps exposure time of a framing camera using pulse-dilation technology and a magnetic lens

    NASA Astrophysics Data System (ADS)

    Bai, Yanli; Long, Jinghua; Liu, Jinyuan; Cai, Houzhi; Niu, Lihong; Zhang, Dongfang; Ma, Xue; Liu, Dan; Yang, Qinlao; Niu, Hanben

    2015-12-01

    A framing camera with high temporal and spatial resolution is demonstrated using pulse-dilation technology and a magnetic lens. The magnetic field of the magnetic lens is simulated using LORENTZ-3EM software, and the magnetic field distribution on-axis is similar to a Gaussian function. The temporal and spatial resolutions of the instrument are measured using light at the wavelength of 266 nm from a frequency tripled femtosecond laser. The measured exposure time of this camera is ˜11 ps, and the spatial resolution is better than 100 μm.

  4. Preliminary Tuft Testing of Metallic Bristles Versus PS212, PS300, and HVOF300

    NASA Technical Reports Server (NTRS)

    Fellenstein, James A.; DellaCorte, Christopher

    1998-01-01

    Turbine engine brush seals are designed with sacrificial brushes and hard shaft coatings to minimize shaft wear and reduce the cost of engine overhauls. Replacing a worm seal is more cost and time effective than refinishing an engine shaft. However, this tribological design causes excessive brush wear and reduces long term seal efficiency. An alternative approach is to coat the shaft with a solid lubricant and allow the bristles to wear into the shaft coating similar to traditional abradable labyrinth seals. This approach can result in reduced seal leakage by forcing the leakage to flow through the seal bristle pack or through a more tortuous shaft wear track. Key to this approach is limiting the shaft wear to an acceptable level were surface refinishing would not be required during every engine overhaul. Included in this paper are brush seal tuft test results for four metallic bristles (nickel-chrome or cobalt-chrome based superalloys) tested against three solid lubricant coatings (NASA's PS212, PS300, and HVOF300). These test results are also compared to previous baseline tests conducted with plasma sprayed chrome carbide. Compared to the baseline results, no tribological benefit was achieved with the metallic bristle/solid lubricant tribopairs tested. To improve the performance of the solid lubricant coatings, issues regarding lubricant phase sizes (homogeneity), and composition need to be addressed.

  5. Phosphatidylserine (PS) Is Exposed in Choroidal Neovascular Endothelium: PS-Targeting Antibodies Inhibit Choroidal Angiogenesis In Vivo and Ex Vivo

    PubMed Central

    Li, Tao; Aredo, Bogale; Zhang, Kaiyan; Zhong, Xin; Pulido, Jose S.; Wang, Shusheng; He, Yu-Guang; Huang, Xianming; Brekken, Rolf A.; Ufret-Vincenty, Rafael L.

    2015-01-01

    Purpose Choroidal neovascularization (CNV) accounts for 90% of cases of severe vision loss in patients with advanced age-related macular degeneration. Identifying new therapeutic targets for CNV may lead to novel combination therapies to improve outcomes and reduce treatment burden. Our goal was to test whether phosphatidylserine (PS) becomes exposed in the outer membrane of choroidal neovascular endothelium, and whether this could provide a new therapeutic target for CNV. Methods Choroidal neovascularization was induced in C57BL/6J mice using laser photocoagulation. Choroidal neovascularization lesions costained for exposed PS and for intercellular adhesion molecule 2 (or isolectin B4) were imaged in flat mounts and in cross sections. The laser CNV model and a choroidal sprouting assay were used to test the effect of PS-targeting antibodies on choroidal angiogenesis. Choroidal neovascularization lesion size was determined by intercellular adhesion molecule 2 (ICAM-2) staining of flat mounts. Results We found that PS was exposed in CNV lesions and colocalized with vascular endothelial staining. Treatment with PS-targeting antibodies led to a 40% to 80% reduction in CNV lesion area when compared to treatment with a control antibody. The effect was the same as that seen using an equal dose of an anti-VEGF antibody. Results were confirmed using the choroid sprouting assay, an ex vivo model of choroidal angiogenesis. Conclusions We demonstrated that PS is exposed in choroidal neovascular endothelium. Furthermore, targeting this exposed PS with antibodies may be of therapeutic value in CNV. PMID:26529048

  6. Cryoannealing-induced space-group transition of crystals of the carbonic anhydrase psCA3.

    PubMed

    Pinard, Melissa A; Kurian, Justin J; Aggarwal, Mayank; Agbandje-McKenna, Mavis; McKenna, Robert

    2016-07-01

    Cryoannealing has been demonstrated to improve the diffraction quality and resolution of crystals of the β-carbonic anhydrase psCA3 concomitant with a change in space group. After initial flash-cooling in a liquid-nitrogen cryostream an X-ray diffraction data set from a psCA3 crystal was indexed in space group P21212 and was scaled to 2.6 Å resolution, but subsequent cryoannealing studies revealed induced protein rearrangements in the crystal contacts, which transformed the space group to I222, with a corresponding improvement of 0.7 Å in resolution. Although the change in diffraction resolution was significant, only minor changes in the psCA3 structure, which retained its catalytic `open' conformation, were observed. These findings demonstrate that cryoannealing can be successfully utilized to induce higher diffraction-quality crystals while maintaining enzymatically relevant conformations and may be useful as an experimental tool for structural studies of other enzymes where the initial diffraction quality is poor. PMID:27380376

  7. Microfabrication of biomaterials by the sub-ps laser-induced forward transfer process

    NASA Astrophysics Data System (ADS)

    Karaiskou, A.; Zergioti, I.; Fotakis, C.; Kapsetaki, M.; Kafetzopoulos, D.

    2003-03-01

    The precise fabrication of micro-dimensioned patterns of biomaterials by the laser microprinting technique using a sub-ps UV laser is described. An ultrashort UV laser has been used to transfer the biomaterial, with low angular divergence, and deposit it onto the substrate with minimum spread and high spatial resolution. The laser-transferred features of 100 μm×100 μm size have been studied by means of scanning electron microscopy and scanning laser confocal fluorescence microscopy. The analysis of DNA and protein microarrays provides an excellent tool to expand our knowledge of genome functions.

  8. Nano-imprint lithography using poly (methyl methacrylate) (PMMA) and polystyrene (PS) polymers

    NASA Astrophysics Data System (ADS)

    Ting, Yung-Chiang; Shy, Shyi-Long

    2016-04-01

    Nano-imprinting lithography (NIL) technology, as one of the most promising fabrication technologies, has been demonstrated to be a powerful tool for large-area replication up to wafer-level, with features down to nanometer scale. The cost of resists used for NIL is important for wafer-level large-area replication. This study aims to develop capabilities in patterning larger area structure using thermal NIL. The commercial available Poly (Methyl Methacrylate) (PMMA) and Polystyrene (PS) polymers possess a variety of characteristics desirable for NIL, such as low material cost, low bulkvolumetric shrinkage, high spin coating thickness uniformity, high process stability, and acceptable dry-etch resistance. PMMA materials have been utilized for positive electron beam lithography for many years, offering high resolution capability and wide process latitude. In addition, it is preferable to have a negative resist like PMMA, which is a simple polymer with low cost and practically unlimited shelf life, and can be dissolved easily using commercial available Propylene glycol methyl ether acetate (PGMEA) safer solvent to give the preferred film thickness. PS is such a resist, as it undergoes crosslinking when exposed to deep UV light or an electron beam and can be used for NIL. The result is a cost effective patterning larger area structure using thermal nano-imprint lithography (NIL) by using commercial available PMMA and PS ploymers as NIL resists.

  9. Hierarchy of scales in B{yields}PS decays

    SciTech Connect

    Delepine, D.; Lucio M, J. L.; Mendoza S, J. A.; Ramirez, Carlos A.

    2008-08-31

    We show that the naive factorization approach can accommodate the existence of the observed hierarchy of branching ratios for the B{yields}PS decays (P stands for pseudoscalar and S for scalar mesons respectively.

  10. Assessment of slope stability using PS-InSAR technique

    NASA Astrophysics Data System (ADS)

    Dwivedi, R.; Varshney, P.; Tiwari, A.; Singh, A. K.; Dikshit, O.

    2014-11-01

    In this research work, PS-InSAR approach is envisaged to monitor slope stability of landslides prone areas in Nainital and Tehri region of Uttarakhand, India. For the proposed work, Stanford Method for Persistent Scatterers (StaMPS) based PS-InSAR is used for processing ENVISAT ASAR C-Band data stacks of study area which resulted in a time series 1D-Line of Sight (LOS) map of surface displacement. StaMPS efficiently extracted the PS pixels on the unstable slopes in both areas and the time series 1D-LOS displacement map of PS pixels indicates that those areas in Nainital and Tehri region have measurement pixels with maximum displacement away from the satellite of the order of 22 mm/year and 17.6 mm/year respectively

  11. KNb1.75V0.25PS10

    PubMed Central

    Yu, Jaemin; Yun, Hoseop

    2011-01-01

    The title compound, potassium diniobium vanadium phospho­rus deca­sulfide, KNb1.75V0.25PS10, was obtained by reaction of the elements with a eutectic mixture of KCl/LiCl. It is isostructural with the quaternary KNb2PS10, but the Nb sites are occupied by statistically disordered Nb (87.5%) and V (12.5%) atoms. The structure is composed of anionic ∞ 1[M 2PS10]− chains (M = Nb/V) separated from each other by K+ ions. The chain is composed of [MS8] distorted bicapped trigonal prisms and [PS4] tetra­hedra. There are no inter­chain bonding inter­actions. The crystal used for the X-ray analysis was a racemic twin. PMID:21522232

  12. The PS1 Science Mission - Status and Results

    NASA Astrophysics Data System (ADS)

    Chambers, Kenneth C.

    2013-06-01

    PS1, the Pan-STARRS1 Telescope is in its last year of the PS1 Science Mission. Operations of the PS1 System include the Observatory, Telescope, 1.4 Gigapixel Camera, Image Processing Pipeline , PSPS relational database and reduced science product software servers. The PS1 Surveys include: (1) A 3pi Steradian Survey, (2) A Medium Deep survey of 10 PS1 footprints spaced around the sky; (3) A solar system survey optimized for Near Earth Objects, (4) a Stellar Transit Survey; and (5) a Deep Survey of M31. The PS1 3pi Survey has now covered the sky north of dec=-30 with 8 to 12 visits in five bands: g,r,i,z and y or over ~45 epochs per point on sky. The performance of the PS1 system, sky coverage, cadence, and data quality of the surveys will be presented as well as progress in reprocessing of the data taken to date and plans for serving the data to the public. A summary of science highlights will be included. The PS1 Science Consortium consists of The Institute for Astronomy at the University of Hawai'i in Manoa, the Max Planck Institute for Astronomy, Heidelberg and the Max Planck Institute for Extraterrestrial Physics, Garching, The Johns Hopkins University, the University of Durham, the University of Edinburgh, the Queen's University Belfast, the Harvard-Smithsonian Center for Astrophysics, the Los Cumbres Observatory Global Telescope Network Incorporated, and the National Central University of Taiwan, NASA, and NSF.

  13. [Application for Lifestyle disease by iPS cells technologies].

    PubMed

    Takashima, Yasuhiro

    2016-03-01

    Currently it is less advanced to understand the pathology of lifestyle disease by using iPS cells because there is partly less direct connection between life style disease and iPS cells. So much more scientists focus on regenerative medicine such as beta cells therapy using iPS cells technologies. It will be indeed a powerful tool to generate beta cells from iPS cells as even in type2 diabetes patients, hyposecretion of insulin from beta cells in pancreas is one of causes. Another reason is complexity of the pathology of life style disease. There are a lot of reasons to cause lifestyle disease. Lifestyle diseases include cancer, chronic liver disease, Type 2 diabetes, heart disease, metabolic syndrome, chronic renal failure, stroke, and obesity. Since obesity is one of major causes of lifestyle diseases, we want to focus on adipogenesis from iPS cells in this review. We analysed and established the differentiation protocol into adipocytes from mouse ES cells and human iPS cells. The other point in this review is the starting pluripotent cells for differentiation. Quality of pluripotent stem cells are one of most critical factors to succeed in getting well-differentiated cells. Recently, we have developed new naive human pluripotent stem cells (PSC),"Reset cells". Naive PSC have more similar to human epibast cells than conventional human PSC. They will be more ideal cells for differentiation because of their hypomethylated status and earlier stage of development. PMID:26923982

  14. Profiling the microRNA Expression in Human iPS and iPS-derived Retinal Pigment Epithelium

    PubMed Central

    Wang, Heuy-Ching; Greene, Whitney A; Kaini, Ramesh R; Shen-Gunther, Jane; Chen, Hung-I H; Cai, Hong; Wang, Yufeng

    2014-01-01

    The purpose of this study is to characterize the microRNA (miRNA) expression profiles of induced pluripotent stem (iPS) cells and retinal pigment epithelium (RPE) derived from induced pluripotent stem cells (iPS-RPE). MiRNAs have been demonstrated to play critical roles in both maintaining pluripotency and facilitating differentiation. Gene expression networks accountable for maintenance and induction of pluripotency are linked and share components with those networks implicated in oncogenesis. Therefore, we hypothesize that miRNA expression profiling will distinguish iPS cells from their iPS-RPE progeny. To identify and analyze differentially expressed miRNAs, RPE was derived from iPS using a spontaneous differentiation method. MiRNA microarray analysis identified 155 probes that were statistically differentially expressed between iPS and iPS-RPE cells. Up-regulated miRNAs including miR-181c and miR-129–5p may play a role in promoting differentiation, while down-regulated miRNAs such as miR-367, miR-18b, and miR-20b are implicated in cell proliferation. Subsequent miRNA–target and network analysis revealed that these miRNAs are involved in cellular development, cell cycle progression, cell death, and survival. A systematic interrogation of temporal and spatial expression of iPS-RPE miRNAs and their associated target mRNAs will provide new insights into the molecular mechanisms of carcinogenesis, eye differentiation and development. PMID:25392691

  15. 2-ps Hard X-Ray Streak Camera Measurements at Sector 7 Beamline of the Advanced Photon Source

    SciTech Connect

    Chollet, M.; Ahr, B.; Walko, D.A.; Rose-Petruck, C.; Adams, B.

    2011-08-02

    A hard X-ray streak camera capable of 2-ps time resolution is in operation at the Sector 7 beamline of the Advanced Photon Source. It is used for laser-pump, X-ray probe experiments using the Ti:Sapphire femtosecond laser system installed on the beamline. This streak camera, combined with standardized and prealigned experimental setups, can perform time-resolved liquid-phase absorption spectroscopy, reflectivity, and diffraction experiments.

  16. PS2013 Satellite Workshop on Photosynthetic Light-Harvesting Systems

    SciTech Connect

    Niederman, Robert A.; Blankenship, Robert E.; Frank, Harry A.

    2015-02-07

    These funds were used for partial support of the PS2013 Satellite Workshop on Photosynthetic Light-Harvesting Systems, that was held on 8-11 August, 2013, at Washington University, St. Louis, MO. This conference, held in conjunction with the 16th International Congress on Photosynthesis/St. Louis, continued a long tradition of light-harvesting satellite conferences that have been held prior to the previous six international photosynthesis congresses. In this Workshop, the basis was explored for the current interest in replacing fossil fuels with energy sources derived form direct solar radiation, coupled with light-driven electron transport in natural photosynthetic systems and how they offer a valuable blueprint for conversion of sunlight to useful energy forms. This was accomplished through sessions on the initial light-harvesting events in the biological conversion of solar energy to chemically stored energy forms, and how these natural photosynthetic processes serve as a guide to the development of robust bio-hybrid and artificial systems for solar energy conversion into both electricity or chemical fuels. Organized similar to a Gordon Research Conference, a lively, informal and collegial setting was established, highlighting the exchange of exciting new data and unpublished results from ongoing studies. A significant amount of time was set aside for open discussion and interactive poster sessions, with a special session devoted to oral presentations by talented students and postdoctoral fellows judged to have the best posters. This area of research has seen exceptionally rapid progress in recent years, with the availability of a number of antenna protein structures at atomic resolution, elucidation of the molecular surface architecture of native photosynthetic membranes by atomic force microscopy and the maturing of ultrafast spectroscopic and molecular biological techniques for the investigation and manipulation of photosynthetic systems. The conferees

  17. Imaging early demineralization with PS-OCT

    NASA Astrophysics Data System (ADS)

    Kang, Hobin; Jiao, Jane J.; Lee, Chulsung; Darling, Cynthia L.; Fried, Daniel

    2010-02-01

    New methods are needed for the nondestructive measurement of tooth demineralization and remineralization to monitor the progression of incipient caries lesions (tooth decay) for effective nonsurgical intervention and to evaluate the performance of anti-caries treatments such as chemical treatments or laser irradiation. Studies have shown that optical coherence tomography (OCT) has great potential to fulfill this role since it can be used to measure the depth and severity of early lesions with an axial resolution exceeding 10-μm, it is easy to apply in vivo and it can be used to image the convoluted topography of tooth occlusal surfaces. In this paper we attempt to determine the earliest stage at which we can detect significant differences in lesion severity. Automated methods of analysis were used to measure the depth and severity of demineralized bovine enamel produced using a simulated caries model that emulates demineralization in the mouth. Significant differences in the depth and integrated reflectivity from the lesions were detected after only a few hours of demineralization. These results demonstrate that cross polarization OCT is ideally suited for the nondestructive assessment of early demineralization.

  18. SwarmPS: rapid, semi-automated single particle selection software.

    PubMed

    Woolford, David; Ericksson, Geoffery; Rothnagel, Rosalba; Muller, David; Landsberg, Michael J; Pantelic, Radosav S; McDowall, Alasdair; Pailthorpe, Bernard; Young, Paul R; Hankamer, Ben; Banks, Jasmine

    2007-01-01

    Single particle analysis (SPA) coupled with high-resolution electron cryo-microscopy is emerging as a powerful technique for the structure determination of membrane protein complexes and soluble macromolecular assemblies. Current estimates suggest that approximately 10(4)-10(5) particle projections are required to attain a 3A resolution 3D reconstruction (symmetry dependent). Selecting this number of molecular projections differing in size, shape and symmetry is a rate-limiting step for the automation of 3D image reconstruction. Here, we present Swarm(PS), a feature rich GUI based software package to manage large scale, semi-automated particle picking projects. The software provides cross-correlation and edge-detection algorithms. Algorithm-specific parameters are transparently and automatically determined through user interaction with the image, rather than by trial and error. Other features include multiple image handling (approximately 10(2)), local and global particle selection options, interactive image freezing, automatic particle centering, and full manual override to correct false positives and negatives. Swarm(PS) is user friendly, flexible, extensible, fast, and capable of exporting boxed out projection images, or particle coordinates, compatible with downstream image processing suites. PMID:16774837

  19. Pressure Monitoring Using Hybrid fs/ps Rotational CARS

    NASA Technical Reports Server (NTRS)

    Kearney, Sean P.; Danehy, Paul M.

    2015-01-01

    We investigate the feasibility of gas-phase pressure measurements at kHz-rates using fs/ps rotational CARS. Femtosecond pump and Stokes pulses impulsively prepare a rotational Raman coherence, which is then probed by a high-energy 6-ps pulse introduced at a time delay from the Raman preparation. Rotational CARS spectra were recorded in N2 contained in a room-temperature gas cell for pressures from 0.1 to 3 atm and probe delays ranging from 10-330 ps. Using published self-broadened collisional linewidth data for N2, both the spectrally integrated coherence decay rate and the spectrally resolved decay were investigated as means for detecting pressure. Shot-averaged and single-laser-shot spectra were interrogated for pressure and the accuracy and precision as a function of probe delay and cell pressure are discussed. Single-shot measurement accuracies were within 0.1 to 6.5% when compared to a transducer values, while the precision was generally between 1% and 6% of measured pressure for probe delays of 200 ps or more, and better than 2% as the delay approached 300 ps. A byproduct of the pressure measurement is an independent but simultaneous measurement of the gas temperature.

  20. Assessment of dentin remineralization with PS-OCT

    NASA Astrophysics Data System (ADS)

    Manesh, Saman K.; Darling, Cynthia L.; Fried, Daniel

    2009-02-01

    Previous studies have demonstrated that polarization sensitive optical coherence tomography (PS-OCT) can be used to image natural root caries lesions, measure non-destructively the severity of dentin demineralization and determine the efficacy of intervention with anti-caries agents including fluoride and lasers. The objective of this study was to determine if PS-OCT could be used to nondestructively measure the formation of a layer of remineralized dentin on the surface of dentin lesions after exposure to a remineralization solution. In this study images of artificial dentin lesions on extracted human teeth were acquired using PS-OCT after exposure to an artificial demineralizing solution at pH 4.9 for six days and after subsequent exposure to a remineralizing solution at pH 7.0 for 20 days. Polarized light microscopy and microradiography were used to examine histological thin sections from the samples for comparison. PS-OCT successfully measured the formation of a layer of increased mineral content near the lesion surface. PLM and TMR corroborated those results. This study demonstrates the potential use of PS-OCT for the nondestructive measurement of the remineralization of dentin surfaces.

  1. Characterization of crosslinked polystyrene(PS) beads in SBR matrix

    SciTech Connect

    Cha, Yoon-Jong; Choe, Soonja

    1995-12-01

    Monodisperse sized crosslinked polystyrene(PS) beads were prepared by a reaction of semibatch emulsion polymerization with styrene monomer, divinylbenzene(DVB) crosslinking agent and potassium persulfate(K{sub 2}S{sub 2}O{sub 9}) initiator in the absence of emulsifier. The glass transition temperature(T{sub g}) and the mean diameter of the beads were increased from 100{degrees}C to 135{degrees}C and from 402 nm to 532 nm, respectively, for an incorporation of 2 to 10 mol% DVB. Crosslinking density was also linearly increased with DVB content. SEM microphotographs of SBR composite filled with various contents of PS beads revealed that PS beads are relatively well dispersed without changing the spherical shape of the beads in all range of compositions. In stress-strain analysis, elongation at break and tensile strength of SBR composite were increased with the bead content. Applicability of the PS beads as a filler in SBR matrix is tested by plotting Mooney-Rivlin or Guth-Smallwood equations. However, mechanical properties of the composite with the beads were not so excellent as those of the composite with carbon black. Crosslinked PS beads are still tentative as a white color reinforcing filler on SBR matrix.

  2. Molecular signatures of neurodegeneration in the cortex of PS1/PS2 double knockout mice

    PubMed Central

    Mirnics, Károly; Norstrom, Eric M; Garbett, Krassimira; Choi, Se Hoon; Zhang, Xiaoqiong; Ebert, Philip; Sisodia, Sangram S

    2008-01-01

    Background Familial Alzheimer's disease-linked variants of presenilin (PSEN1 and PSEN2) contribute to the pathophysiology of disease by both gain-of-function and loss-of-function mechanisms. Deletions of PSEN1 and PSEN2 in the mouse forebrain result in a strong and progressive neurodegenerative phenotype which is characterized by both anatomical and behavioral changes. Results To better understand the molecular changes associated with these morphological and behavioral phenotypes, we performed a DNA microarray transcriptome profiling of the hippocampus and the frontal cortex of the PSEN1/PSEN2 double knock-out mice and littermate controls at five different ages ranging from 2–8 months. Our data suggest that combined deficiencies of PSEN1 and PSEN2 results in a progressive, age-dependent transcriptome signature related to neurodegeneration and neuroinflammation. While these events may progress differently in the hippocampus and frontal cortex, the most critical expression signatures are common across the two brain regions, and involve a strong upregulation of cathepsin and complement system transcripts. Conclusion The observed neuroinflammatory expression changes are likely to be causally linked to the neurodegenerative phenotype observed in mice with compound deletions of PSEN1 and PSEN2. Furthermore, our results suggest that the evaluation of inhibitors of PS/γ-secretase activity for treatment of Alzheimer's Disease must include close monitoring for signs of calpain-cathepsin system activation. PMID:18834536

  3. SEA and strategy formation theories: From three Ps to five Ps

    SciTech Connect

    Cherp, Aleh Watt, Alan Vinichenko, Vadim

    2007-10-15

    A transition to environmentally sustainable societies should involve a significant and comprehensive - strategic - change. Much of the promise of SEA is associated precisely with its perceived capacity to facilitate such a strategic transformation by influencing selected 'strategic decisions'. This paper examines the potential effectiveness and limitations of such an approach in light of contemporary organizational strategy theories. Most of these theories separate 'strategies' from 'decisions' and also transcend the notion of strategies as formal plans, policies and programs (PPPs). Instead, they consider strategies as 'five Ps', adding 'Position', 'Perspective', 'Pattern' and 'Ploy' to the 'Plan'. Lessons from organizational strategy formation give rise to the following challenges for SEA theory and practice: 1.How to assess and influence informal as well as formal aspects of strategic initiatives? 2.How to extend SEA 'beyond decisions' to address 'emergent strategies' where strategic action is not necessarily preceded by a decision? 3.How to ensure that knowledge provided as a result of SEA is strategically relevant and communicated to key players in strategy formation? 4.How to deal with an uncontrollable and unpredictable environment in which strategic initiatives unfold? 5.How to recognize those situations when SEA can have most strategic influence? This paper takes a step towards examining these challenges by exploring the intellectual history of SEA in light of the main strategy formation theories and by identifying directions in which the SEA discourse may be further enhanced to meet these five challenges.

  4. Discriminating the effects of phylogenetic hypothesis, tree resolution and clade age estimates on phylogenetic signal measurements.

    PubMed

    Seger, G D S; Duarte, L D S; Debastiani, V J; Kindel, A; Jarenkow, J A

    2013-09-01

    Understanding how species traits evolved over time is the central question to comprehend assembly rules that govern the phylogenetic structure of communities. The measurement of phylogenetic signal (PS) in ecologically relevant traits is a first step to understand phylogenetically structured community patterns. The different methods available to estimate PS make it difficult to choose which is most appropriate. Furthermore, alternative phylogenetic tree hypotheses, node resolution and clade age estimates might influence PS measurements. In this study, we evaluated to what extent these parameters affect different methods of PS analysis, and discuss advantages and disadvantages when selecting which method to use. We measured fruit/seed traits and flowering/fruiting phenology of endozoochoric species occurring in Southern Brazilian Araucaria forests and evaluated their PS using Mantel regressions, phylogenetic eigenvector regressions (PVR) and K statistic. Mantel regressions always gave less significant results compared to PVR and K statistic in all combinations of phylogenetic trees constructed. Moreover, a better phylogenetic resolution affected PS, independently of the method used to estimate it. Morphological seed traits tended to show higher PS than diaspores traits, while PS in flowering/fruiting phenology depended mostly on the method used to estimate it. This study demonstrates that different PS estimates are obtained depending on the chosen method and the phylogenetic tree resolution. This finding has implications for inferences on phylogenetic niche conservatism or ecological processes determining phylogenetic community structure. PMID:23368095

  5. Influence of the external DEM on PS-InSAR processing and results on Northern Appennine slopes

    NASA Astrophysics Data System (ADS)

    Bayer, B.; Schmidt, D. A.; Simoni, A.

    2014-12-01

    We present an InSAR analysis of slow moving landslide in the Northern Appennines, Italy, and assess the dependencies on the choice of DEM. In recent years, advanced processing techniques for synthetic aperture radar interferometry (InSAR) have been applied to measure slope movements. The persistent scatterers (PS-InSAR) approach is probably the most widely used and some codes are now available in the public domain. The Stanford method of Persistent Scatterers (StamPS) has been successfully used to analyze landslide areas. One problematic step in the processing chain is the choice of an external DEM that is used to model and remove the topographic phase in a series of interferograms in order to obtain the phase contribution caused by surface deformation. The choice is not trivial, because the PS InSAR results differ significantly in terms of PS identification, positioning, and the resulting deformation signal. We use four different DEMs to process a set of 18 ASAR (Envisat) scenes over a mountain area (~350 km2) of the Northern Appennines of Italy, using StamPS. Slow-moving landslides control the evolution of the landscape and cover approximately 30% of the territory. Our focus in this presentation is to evaluate the influence of DEM resolution and accuracy by comparing PS-InSAR results. On an areal basis, we perform a statistical analysis of displacement time-series to make the comparison. We also consider two case studies to illustrate the differences in terms of PS identification, number and estimated displacements. It is clearly shown that DEM accuracy positively influences the number of PS, while line-of-sight rates differ from case to case and can result in deformation signals that are difficult to interpret. We also take advantage of statistical tools to analyze the obtained time-series datasets for the whole study area. Results indicate differences in the style and amount of displacement that can be related to the accuracy of the employed DEM.

  6. The nonconserved hydrophilic loop domain of presenilin (PS) is not required for PS endoproteolysis or enhanced abeta 42 production mediated by familial early onset Alzheimer's disease-linked PS variants.

    PubMed

    Saura, C A; Tomita, T; Soriano, S; Takahashi, M; Leem, J Y; Honda, T; Koo, E H; Iwatsubo, T; Thinakaran, G

    2000-06-01

    Presenilin 1 (PS1) and presenilin 2 (PS2) are polytopic membrane proteins that are mutated in the majority of early onset familial Alzheimer's disease (FAD) cases. Two lines of evidence establish a critical role for PS in the production of beta-amyloid peptides (Abeta). FAD-linked PS mutations elevate the levels of highly amyloidogenic Abeta ending at residue 42 (Abeta42), and cells with ablated PS1 alleles secrete low levels of Abeta. Several recent reports have shown that the hydrophilic loop (HL) domain, located between transmembrane domains 6 and 7, contains sites for phosphorylation, caspase cleavage, and sequences that bind several PS-interacting proteins. In the present report, we examined the metabolism of PS polypeptides lacking the HL domain and the influence of these molecules on Abeta production. We report that the deletion of the HL domain does not have a deleterious effect on the regulated endoproteolysis of PS, saturable accumulation of PS fragments, or the self-association of PS fragments. Abeta production was not significantly altered in cells expressing HL-deleted PS polypeptides compared with cells expressing full-length PS. Importantly, deletion of the HL domain did not affect FAD mutation-mediated elevation in the production of Abeta42. Furthermore, the deletion of the HL domain did not impair the role of PS1 or PS2 in facilitating Notch processing. Thus, our results argue against a biologically or pathologically relevant role for the HL domain phosphorylation and caspase cleavage and the association of PS HL domain-interacting proteins, in amyloid precursor protein metabolism and Abeta production or Notch cleavage. PMID:10748144

  7. Effect of interfaces on the melting of PEO confined in triblock PS-b-PEO-b-PS copolymers.

    PubMed

    Beaudoin, E; Phan, T N T; Robinet, M; Denoyel, R; Davidson, P; Bertin, D; Bouchet, R

    2013-08-27

    Block copolymers form nanostructures that have interesting physical properties because they combine, for a single compound, the complementary features brought by each block. However, in order to fully exploit these properties, the physical state of each kind of domain must be precisely controlled. In this work, triblock PS-b-PEO-b-PS copolymers consisting of a central poly(ethylene oxide) (PEO) block covalently bonded to polystyrene (PS) blocks were synthesized by Atom Transfer Radical Polymerization. Their morphology was investigated by X-ray scattering and TEM experiments whereas their thermodynamic behavior was characterized by DSC. A strong decrease of both the melting temperature and the degree of crystallinity of PEO, due to its confinement between the PS domains, was observed and analyzed with a modified Gibbs-Thomson equation, following the approaches used for fluids confined in porous media. The existence of an amorphous bound layer, a few nanometers thick, at the PEO/PS interface, that does not undergo any phase transition in the temperature range investigated, accounts for both the melting temperature depression and the decrease of crystallinity upon confinement. This interfacial layer may significantly affect the mechanical and transport properties of these block copolymers that find applications as solid polymer electrolytes in batteries for example. Moreover, the value obtained for the solid PEO/liquid PEO surface tension is lower than those previously published but is thermodynamically consistent with the surface tensions of polymers at the solid/vapor and liquid/vapor interfaces. PMID:23865710

  8. Physiologically generated presenilin 1 lacking exon 8 fails to rescue brain PS1−/− phenotype and forms complexes with wildtype PS1 and nicastrin

    PubMed Central

    Brautigam, Hannah; Moreno, Cesar L.; Steele, John W.; Bogush, Alexey; Dickstein, Dara L.; Kwok, John B.J.; Schofield, Peter R.; Thinakaran, Gopal; Mathews, Paul M.; Hof, Patrick R.; Gandy, Sam; Ehrlich, Michelle E.

    2015-01-01

    The presenilin 1 (PSEN1) L271V mutation causes early-onset familial Alzheimer’s disease by disrupting the alternative splicing of the PSEN1 gene, producing some transcripts harboring the L271V point mutation and other transcripts lacking exon 8 (PS1∆exon8). We previously reported that PS1 L271V increased amyloid beta (Aβ) 42/40 ratios, while PS1∆exon8 reduced Aβ42/40 ratios, indicating that the former and not the exon 8 deletion transcript is amyloidogenic. Also, PS1∆exon8 did not rescue Aβ generation in PS1/2 double knockout cells indicating its identity as a severe loss-of-function splice form. PS1∆exon8 is generated physiologically raising the possibility that we had identified the first physiological inactive PS1 isoform. We studied PS1∆exon8 in vivo by crossing PS1∆exon8 transgenics with either PS1-null or Dutch APPE693Q mice. As a control, we crossed APPE693Q with mice expressing a deletion in an adjacent exon (PS1∆exon9). PS1∆exon8 did not rescue embryonic lethality or Notch-deficient phenotypes of PS1-null mice displaying severe loss of function in vivo. We also demonstrate that this splice form can interact with wildtype PS1 using cultured cells and co-immunoprecipitation (co-IP)/bimolecular fluorescence complementation. Further co-IP demonstrates that PS1∆exon8 interacts with nicastrin, participating in the γ–secretase complex formation. These data support that catalytically inactive PS1∆exon8 is generated physiologically and participates in protein-protein interactions. PMID:26608390

  9. Physiologically generated presenilin 1 lacking exon 8 fails to rescue brain PS1-/- phenotype and forms complexes with wildtype PS1 and nicastrin.

    PubMed

    Brautigam, Hannah; Moreno, Cesar L; Steele, John W; Bogush, Alexey; Dickstein, Dara L; Kwok, John B J; Schofield, Peter R; Thinakaran, Gopal; Mathews, Paul M; Hof, Patrick R; Gandy, Sam; Ehrlich, Michelle E

    2015-01-01

    The presenilin 1 (PSEN1) L271V mutation causes early-onset familial Alzheimer's disease by disrupting the alternative splicing of the PSEN1 gene, producing some transcripts harboring the L271V point mutation and other transcripts lacking exon 8 (PS1(∆exon8)). We previously reported that PS1 L271V increased amyloid beta (Aβ) 42/40 ratios, while PS1(∆exon8) reduced Aβ42/40 ratios, indicating that the former and not the exon 8 deletion transcript is amyloidogenic. Also, PS1(∆exon8) did not rescue Aβ generation in PS1/2 double knockout cells indicating its identity as a severe loss-of-function splice form. PS1(∆exon8) is generated physiologically raising the possibility that we had identified the first physiological inactive PS1 isoform. We studied PS1(∆exon8) in vivo by crossing PS1(∆exon8) transgenics with either PS1-null or Dutch APP(E693Q) mice. As a control, we crossed APP(E693Q) with mice expressing a deletion in an adjacent exon (PS1(∆exon9)). PS1(∆exon8) did not rescue embryonic lethality or Notch-deficient phenotypes of PS1-null mice displaying severe loss of function in vivo. We also demonstrate that this splice form can interact with wildtype PS1 using cultured cells and co-immunoprecipitation (co-IP)/bimolecular fluorescence complementation. Further co-IP demonstrates that PS1(∆exon8) interacts with nicastrin, participating in the γ-secretase complex formation. These data support that catalytically inactive PS1(∆exon8) is generated physiologically and participates in protein-protein interactions. PMID:26608390

  10. Dynamic regional phase synchrony (DRePS): An Instantaneous Measure of Local fMRI Connectivity Within Spatially Clustered Brain Areas.

    PubMed

    Omidvarnia, Amir; Pedersen, Mangor; Walz, Jennifer M; Vaughan, David N; Abbott, David F; Jackson, Graeme D

    2016-05-01

    Dynamic functional brain connectivity analysis is a fast expanding field in computational neuroscience research with the promise of elucidating brain network interactions. Sliding temporal window based approaches are commonly used in order to explore dynamic behavior of brain networks in task-free functional magnetic resonance imaging (fMRI) data. However, the low effective temporal resolution of sliding window methods fail to capture the full dynamics of brain activity at each time point. These also require subjective decisions regarding window size and window overlap. In this study, we introduce dynamic regional phase synchrony (DRePS), a novel analysis approach that measures mean local instantaneous phase coherence within adjacent fMRI voxels. We evaluate the DRePS framework on simulated data showing that the proposed measure is able to estimate synchrony at higher temporal resolution than sliding windows of local connectivity. We applied DRePS analysis to task-free fMRI data of 20 control subjects, revealing ultra-slow dynamics of local connectivity in different brain areas. Spatial clustering based on the DRePS feature time series reveals biologically congruent local phase synchrony networks (LPSNs). Taken together, our results demonstrate three main findings. Firstly, DRePS has increased temporal sensitivity compared to sliding window correlation analysis in capturing locally synchronous events. Secondly, DRePS of task-free fMRI reveals ultra-slow fluctuations of ∼0.002-0.02 Hz. Lastly, LPSNs provide plausible spatial information about time-varying brain local phase synchrony. With the DRePS method, we introduce a framework for interrogating brain local connectivity, which can potentially provide biomarkers of human brain function in health and disease. Hum Brain Mapp 37:1970-1985, 2016. © 2016 Wiley Periodicals, Inc. PMID:27019380

  11. Isolation of PsPIN2 and PsAUX1 from etiolated pea epicotyls and their expression on a three-dimensional clinostat

    NASA Astrophysics Data System (ADS)

    Hoshino, Tomoki; Hitotsubashi, Reiko; Miyamoto, Kensuke; Tanimoto, Eiichi; Ueda, Junichi

    We isolated novel cDNAs containing the complete open reading frames of a putative auxin influx carrier, PsAUX1, and a putative auxin efflux carrier, PsPIN2, from etiolated pea epicotyls. High levels of homology were found on nucleotide and deduced amino acid sequences among PsPIN2, PsPIN1 (Accession No. AY222857) and AtPINs. Phylogenetic analyses based on deduced amino acid sequences revealed that PsPIN2 belonged to a subclade including AtPIN3, AtPIN4 and AtPIN7, while PsPIN1 belonged to the same clade as AtPIN1. The results were similar for PsAUX1 and AtAUX1, where PsAUX1 belongs to the same subclade as AtAUX1 and CS-AUX1. Expression of PsPIN1, PsPIN2 and PsAUX1 in pea epicotyl segments was promoted upon incubation of the segments with auxin (indole-3-acetic acid). In 3.5-d-old etiolated pea seedlings, relatively high expression of PsPIN1 and PsAUX1 was observed in the hook region, growing epicotyls and root tips as compared with those in mature regions of epicotyls and roots. Expression of PsPIN2 in roots was less than that in shoots. Simulated microgravity conditions on a three-dimensional clinostat remarkably increased gene expression of PsPIN1 and PsAUX1 in the hook and the internodes of pea epicotyls, but the increase in PsPIN2 was less. In contrast, polar auxin transport of pea epicotyls was substantially suppressed under simulated microgravity conditions on a 3D clinostat, similar to data from a space experiment on STS-95. These results suggest that PsPINs and PsAUX1 are auxin-inducible genes, and that the expression of PsPINs and PsAUX1 genes is sensitive to gravistimulation.

  12. Watching a signaling protein function in real time via 100-ps time-resolved Laue crystallography

    SciTech Connect

    Schotte, Friedrich; Cho, Hyun Sun; Kaila, Ville R.I.; Kamikubo, Hironari; Dashdorj, Naranbaatar; Henry, Eric R.; Graber, Timothy J.; Henning, Robert; Wulff, Michael; Hummer, Gerhard; Kataoka, Mikio; Anfinrud, Philip A.

    2012-11-06

    To understand how signaling proteins function, it is necessary to know the time-ordered sequence of events that lead to the signaling state. We recently developed on the BioCARS 14-IDB beamline at the Advanced Photon Source the infrastructure required to characterize structural changes in protein crystals with near-atomic spatial resolution and 150-ps time resolution, and have used this capability to track the reversible photocycle of photoactive yellow protein (PYP) following trans-to-cis photoisomerization of its p-coumaric acid (pCA) chromophore over 10 decades of time. The first of four major intermediates characterized in this study is highly contorted, with the pCA carbonyl rotated nearly 90° out of the plane of the phenolate. A hydrogen bond between the pCA carbonyl and the Cys69 backbone constrains the chromophore in this unusual twisted conformation. Density functional theory calculations confirm that this structure is chemically plausible and corresponds to a strained cis intermediate. This unique structure is short-lived (~600 ps), has not been observed in prior cryocrystallography experiments, and is the progenitor of intermediates characterized in previous nanosecond time-resolved Laue crystallography studies. The structural transitions unveiled during the PYP photocycle include trans/cis isomerization, the breaking and making of hydrogen bonds, formation/relaxation of strain, and gated water penetration into the interior of the protein. This mechanistically detailed, near-atomic resolution description of the complete PYP photocycle provides a framework for understanding signal transduction in proteins, and for assessing and validating theoretical/computational approaches in protein biophysics.

  13. Watching a signaling protein function in real time via 100-ps time-resolved Laue crystallography

    PubMed Central

    Schotte, Friedrich; Cho, Hyun Sun; Kaila, Ville R. I.; Kamikubo, Hironari; Dashdorj, Naranbaatar; Henry, Eric R.; Graber, Timothy J.; Henning, Robert; Wulff, Michael; Hummer, Gerhard; Kataoka, Mikio; Anfinrud, Philip A.

    2012-01-01

    To understand how signaling proteins function, it is crucial to know the time-ordered sequence of events that lead to the signaling state. We recently developed on the BioCARS 14-IDB beamline at the Advanced Photon Source the infrastructure required to characterize structural changes in protein crystals with near-atomic spatial resolution and 150-ps time resolution, and have used this capability to track the reversible photocycle of photoactive yellow protein (PYP) following trans-to-cis photoisomerization of its p-coumaric acid (pCA) chromophore over 10 decades of time. The first of four major intermediates characterized in this study is highly contorted, with the pCA carbonyl rotated nearly 90° out of the plane of the phenolate. A hydrogen bond between the pCA carbonyl and the Cys69 backbone constrains the chromophore in this unusual twisted conformation. Density functional theory calculations confirm that this structure is chemically plausible and corresponds to a strained cis intermediate. This unique structure is short-lived (∼600 ps), has not been observed in prior cryocrystallography experiments, and is the progenitor of intermediates characterized in previous nanosecond time-resolved Laue crystallography studies. The structural transitions unveiled during the PYP photocycle include trans/cis isomerization, the breaking and making of hydrogen bonds, formation/relaxation of strain, and gated water penetration into the interior of the protein. This mechanistically detailed, near-atomic resolution description of the complete PYP photocycle provides a framework for understanding signal transduction in proteins, and for assessing and validating theoretical/computational approaches in protein biophysics. PMID:23132943

  14. Consistent scenario for B{yields}PS decays

    SciTech Connect

    Delepine, D.; Lucio M, J. L.; Mendoza S, J. A.; Ramirez, Carlos A.

    2008-12-01

    We consider B{yields}PS decays where P stands for pseudoscalar and S for a heavy (1500 MeV) scalar meson. We achieve agreement with available experimental data, which includes two orders of magnitude hierarchy, assuming the scalars mesons are two quark states. The contribution of the dipolar penguin operator O{sub 11} is quantified.

  15. BioMaPS: A Roadmap for Success

    ERIC Educational Resources Information Center

    McCarthy, Maeve L.; Fister, K. Renee

    2010-01-01

    The manuscript outlines the impact that our National Science Foundation Interdisciplinary Training for Undergraduates in Biological and Mathematical Sciences program, BioMaPS, has had on the students and faculty at Murray State University. This interdisciplinary program teams mathematics and biology undergraduate students with mathematics and…

  16. Framing Retention for Institutional Improvement: A 4 Ps Framework

    ERIC Educational Resources Information Center

    Kalsbeek, David H.

    2013-01-01

    A 4 Ps framework for student retention strategy is a construct for reframing the retention discussion in a way that enables institutional improvement by challenging some conventional wisdom and prevailing perspectives that have characterized retention strategy for years. It opens new possibilities for action and improvement by suggesting that…

  17. Near-threshold Ps(n=2)-p scattering

    NASA Astrophysics Data System (ADS)

    Fabrikant, Ilya; Bray, Igor

    2016-05-01

    We study the threshold behavior of elastic and inelastic collisions of the excited positronium (Ps) atom with the proton using the theory developed by Gailitis. We show that partial cross sections for elastic and quasielastic processes exhibit pronounced oscillations above the threshold and diverge as 1 / E where E is the collision energy. This behavior is limited from below by the energy equal to the relativistic splitting between degenerate Ps states. Ab initio close coupling calculations are in excellent agreement with the results of the threshold theory. The oscillations almost completely disappear in the total (summed over partial waves) cross sections. However, dipole-supported resonances appear in inelastic processes, in particular in the important process Ps(nl) + p --> H(n'l') +e+ below higher-energy thresholds. Above thresholds these cross sections don't exhibit oscillations but have the 1 / E divergence in an exothermic case. These results are important for current attempts to produce antihydrogen in a similar charge-conjugated reaction Ps(nl) + p --> H (n'l') +e- . Supported by the US National Science Foundation.

  18. Directionality of Electron Transfer in Type I Reaction Center Proteins: High-Frequency EPR Study of PS I with Removed Iron-Sulfur Centers.

    PubMed

    Poluektov, Oleg G; Utschig, Lisa M

    2015-10-29

    A key step of photosynthetic solar energy conversion involves rapid light-induced sequential electron-transfer steps that result in the formation of a stabilized charge-separated state. These primary reactions take place in large integral membrane reaction center (RC) proteins, wherein a series of donor/acceptor cofactors are specifically positioned for efficient electron transfer. RCs can be divided in two classes, Type I and Type II and examples of both types, photosystem I (PS I) and photosystem II (PS II), are involved in the oxygenic photosynthesis of higher plants, cyanobacteria, and algae. High-resolution X-ray crystal structures reveal that PS I and PS II contain two nearly symmetric branches of redox cofactors, termed the A and B branches. While unidirectional ET along the A branch in Type II RCs is well established, there is still a debate of whether primary photochemistry in Type I RCs is unidirectional along the A branch or bidirectional proceeding down both of the A and B branches. Light-induced electron transfer through the B branch has been observed in genetically modified PS I and in native PS I pretreated with strong reducing conditions to reduce three [4Fe-4S] clusters, the terminal electron acceptors of PS I; however, the extent of asymmetry of ET along both cofactor branches remains an open question. To prove that bidirectional ET in PS I is not simply an artifact of a reducing environment or genetic modification and to determine the degree of PS I ET asymmetry, we have examined biochemically modified Synechococcus leopoliensis PS I RCs, wherein the [4Fe-4S] clusters FX, FA, and FB have been removed to prevent secondary ET from phylloquinones (A1A/A1B) to FX. For these Fe-removed proteins, we observe that ET along both the A and B branches occurs with a ratio close to 1. Together with previously reported data, the concomitant structural and kinetic information obtained with HF EPR unambiguously proves the bidirectional nature of ET in PS I over

  19. Time-gated single-photon detection module with 110 ps transition time and up to 80 MHz repetition rate

    SciTech Connect

    Buttafava, Mauro Boso, Gianluca; Ruggeri, Alessandro; Tosi, Alberto; Dalla Mora, Alberto

    2014-08-15

    We present the design and characterization of a complete single-photon counting module capable of time-gating a silicon single-photon avalanche diode with ON and OFF transition times down to 110 ps, at repetition rates up to 80 MHz. Thanks to this sharp temporal filtering of incoming photons, it is possible to reject undesired strong light pulses preceding (or following) the signal of interest, allowing to increase the dynamic range of optical acquisitions up to 7 decades. A complete experimental characterization of the module highlights its very flat temporal response, with a time resolution of the order of 30 ps. The instrument is fully user-configurable via a PC interface and can be easily integrated in any optical setup, thanks to its small and compact form factor.

  20. Emerging roles for lysophosphatidylserine in resolution of inflammation

    PubMed Central

    Frasch, S. Courtney; Bratton, Donna L.

    2012-01-01

    Despite overlapping structural aspects with other phospholipids, lysophosphatidylserine (lysoPS), the monoacyl derivative of phosphatidylserine (diacylPS), appears to exert unique signaling characteristics important in both the early stages of initiating acute inflammation and in the orchestration of its resolution. LysoPS has long been known as a signaling phospholipid in mast cell biology, markedly enhancing stimulated histamine release and eicosanoid production. More recently, there has been a resurgence of interest in lysoPS as new roles in the promotion of phagocytosis of apoptotic cells, so-called efferocytosis, and resolution of inflammation have been identified. With regard to the latter, lysoPS generated in/on activated or aged apoptotic neutrophils enhances their clearance by macrophages via signaling through the macrophage G-protein coupled receptor G2A. In macrophages, this early acting pathway results in PKA-dependent augmentation of Rac1 activity via increased production of PGE2 and cAMP. As such, macrophages stimulated with lysoPS demonstrate significantly increased efferocytic capacity necessary to clear large numbers of recruited neutrophils typical of acute inflammation. Given that clearance of these cells is critical for restoration of tissue function, lysoPS, as a pro-resolving lipid mediator, is hypothesized to play a key role in promoting timely resolution of inflammation. This article will review our current knowledge of lysoPS biology including receptor signaling and mechanisms of generation as well as summarize the more recent evidence of its expanding roles in inflammation. PMID:22465125

  1. Capturing molecular structural dynamics by 100 ps time-resolved X-ray absorption spectroscopy.

    PubMed

    Sato, Tokushi; Nozawa, Shunsuke; Ichiyanagi, Kohei; Tomita, Ayana; Chollet, Matthieu; Ichikawa, Hirohiko; Fujii, Hiroshi; Adachi, Shin Ichi; Koshihara, Shin Ya

    2009-01-01

    An experimental set-up for time-resolved X-ray absorption spectroscopy with 100 ps time resolution at beamline NW14A at the Photon Factory Advanced Ring is presented. The X-ray positional active feedback to crystals in a monochromator combined with a figure-of-merit scan of the laser beam position has been utilized as an essential tool to stabilize the spatial overlap of the X-ray and laser beams at the sample position. As a typical example, a time-resolved XAFS measurement of a photo-induced spin crossover reaction of the tris(1,10-phenanthrorine)iron(II) complex in water is presented. PMID:19096182

  2. Spectra and relaxation dynamics of the pseudohalide (PS) vibrational bands for Ru(bpy)2(PS)2 complexes, PS = CN, NCS and N3

    NASA Astrophysics Data System (ADS)

    Compton, Ryan; Gerardi, Helen K.; Weidinger, Daniel; Brown, Douglas J.; Dressick, Walter J.; Heilweil, Edwin J.; Owrutsky, Jeffrey C.

    2013-08-01

    Static and transient infrared spectroscopy were used to investigate cis-Ru(bpy)2(N3)2 (bpy = 2,2‧-bipyridine), cis-Ru(bpy)2(NCS)2, and cis-Ru(bpy)2(CN)2 in solution. The NC stretching IR band for cis-Ru(bpy)2(NCS)2 appears at higher frequency (∼2106 cm-1 in DMSO) than for the free NCS- anion while the IR bands for the azide and cyanide complexes are closer to those of the respective free anions. The vibrational energy relaxation (VER) lifetime for the azide complex is found to be much shorter (∼5 ps) than for either the NCS or CN species (both ∼70 ps in DMSO) and the lifetimes resemble those for each corresponding free anion in solution. However, for cis-Ru(bpy)2(N3)2, it is determined that the transition frequency depends more on the solvent than the VER lifetime implying that intramolecular vibrational relaxation is predominant over solvent energy-extracting interactions. These results are compared to the behavior of other related metal complexes in solution.

  3. The CERN PS/SL Controls Java Application Programming Interface

    SciTech Connect

    I. Deloose; J. Cuperus; P. Charrue; F. DiMaio; K. Kostro; M. Vanden Eynden; W. Watson

    1999-10-01

    The PS/SL Convergence Project was launched in March 1998. Its objective is to deliver a common control as infrastructure for the CERN accelerators by year 2001. In the framework of this convergence activity, a project was launched to develop a Java Application Programming Interface (API) between programs written in the Java language and the PS and SL accelerator equipment. This Java API was specified and developed in collaboration with TJNAF. It is based on the Java CDEV [1] package that has been extended in order to end up with a CERN/TJNAF common product. It implements a detailed model composed of devices organized in named classes that provide a property-based interface. It supports data subscription and introspection facilities. The device model is presented and the capabilities of the API are described with syntax examples. The software architecture is also described.

  4. Direct molding of nanopatterned polymeric films: Resolution and errors

    NASA Astrophysics Data System (ADS)

    Azzaroni, O.; Schilardi, P. L.; Salvarezza, R. C.; Gago, R.; Vázquez, L.

    2003-01-01

    The capability of the direct polymer molding method to transfer ordered nanopatterns from a surface-modified silicon template to polymeric materials, such as polystyrene (PS) and high-impact polystyrene (HIPS) is investigated by tapping mode atomic force microscopy (AFM). The lateral resolution of the method for both materials is 54±1 nm while the vertical resolution is 5±1 nm and 3±1 nm, for PS and HIPS, respectively. This difference is explained by considering the different nanomechanical properties of the polymers. In contrast, HIPS surfaces are more resistant to the wear induced by the repetitive "reading" of the surface structure with the AFM tip.

  5. The four "P"s of marketing are dead.

    PubMed

    English, J

    2000-01-01

    For several decades marketing planning in the United States has relied upon the "four Ps" model. Product, price, place, and promotion were considered the foundation of the marketing mix. This model, however, has never been a comfortable fit for health care and, as the new century dawns, we find that a new marketing model--emphasizing the "four Rs"--is emerging. The foundations of the new model are relevance, response, relationships, and results. PMID:11183425

  6. Large-area 200-ps gated microchannel plate detector

    SciTech Connect

    Eckart, M.J.; Hanks, R.L.; Kilkenny, J.D.; Pasha, R.; Wiedwald, J.D.; Hares, J.D.

    1986-08-01

    Results are presented with a 15-mm-wide gated microchannel plate UV and x-ray detector. The active area is part of a 6-..cap omega.. transmission line driven by an electronically generated gate pulse. The microchannel plate is coated with CsI allowing tests with a frequency-quadrupoled, high-repetition-rate 1.05-..mu..m laser. Results showing optical gate widths as short as 100 ps are presented.

  7. PS3 CELL Development for Scientific Computation and Research

    NASA Astrophysics Data System (ADS)

    Christiansen, M.; Sevre, E.; Wang, S. M.; Yuen, D. A.; Liu, S.; Lyness, M. D.; Broten, M.

    2007-12-01

    The Cell processor is one of the most powerful processors on the market, and researchers in the earth sciences may find its parallel architecture to be very useful. A cell processor, with 7 cores, can easily be obtained for experimentation by purchasing a PlayStation 3 (PS3) and installing linux and the IBM SDK. Each core of the PS3 is capable of 25 GFLOPS giving a potential limit of 150 GFLOPS when using all 6 SPUs (synergistic processing units) by using vectorized algorithms. We have used the Cell's computational power to create a program which takes simulated tsunami datasets, parses them, and returns a colorized height field image using ray casting techniques. As expected, the time required to create an image is inversely proportional to the number of SPUs used. We believe that this trend will continue when multiple PS3s are chained using OpenMP functionality and are in the process of researching this. By using the Cell to visualize tsunami data, we have found that its greatest feature is its power. This fact entwines well with the needs of the scientific community where the limiting factor is time. Any algorithm, such as the heat equation, that can be subdivided into multiple parts can take advantage of the PS3 Cell's ability to split the computations across the 6 SPUs reducing required run time by one sixth. Further vectorization of the code can allow for 4 simultanious floating point operations by using the SIMD (single instruction multiple data) capabilities of the SPU increasing efficiency 24 times.

  8. A new shape resonance in the Ps^- system

    NASA Astrophysics Data System (ADS)

    Ho, Yew Kam

    2012-06-01

    There have been continues experimental and theoretical investigations on the positronium negative ion (Ps^-), one of the simplest three-lepton systems interacting through Coulomb forces. In the present work, we use highly correlated Hylleraas wave functions up to N=1078 terms together with employing the complex-coordinate rotation method [1] to investigate resonances in the Ps^- system. We have located a new S-wave shape resonance lying above the Ps (n=2) threshold. Our preliminary results for the resonance parameters are Er = - 0.0498788 a.u. and γ / 2 = 0.0139470 a.u., where Er and γ denote the resonance energy and width, respectively. This stabilized complex eigenvalue has never been reported in the literature, to the best of our knowledge. Here, by changing the mass of the positively charged particle from one unit of the electron mass to infinitely heavy, we have traced this resonance pole from the positronium negative ion to the hydrogen negative ion [2]. Detailed calculations will be presented at the meeting. [4pt] [1]. Y. K. Ho, Phys. Reports 99, 1 (1983) and references therein. [0pt] [2]. A. Burgers and E. Lindroth, Euro. Phys. J. D 10, 327 (2000).

  9. iPS cell transplantation for traumatic spinal cord injury

    PubMed Central

    Goulão, Miguel; Lepore, Angelo C.

    2016-01-01

    A large body of work has been published on transplantation of a wide range of neural stem and progenitor cell types derived from the developing and adult CNS, as well as from pluripotent embryonic stem cells, in models of traumatic spinal cord injury (SCI). However, many of these cell-based approaches present practical issues for clinical translation such as ethical cell derivation, generation of potentially large numbers of homogenously prepared cells, and immune rejection. With the advent of induced Pluripotent Stem (iPS) cell technology, many of these issues may potentially be overcome. To date, a number of studies have demonstrated integration, differentiation into mature CNS lineages, migration and long-term safety of iPS cell transplants in a variety of SCI models, as well as therapeutic benefits in some cases. Given the clinical potential of this advance in stem cell biology, we present a concise review of studies published to date involving iPS cell transplantation in animal models of SCI. PMID:26201863

  10. Stabilization of PS/PLA cocontinuous blends by interfacial graphene

    NASA Astrophysics Data System (ADS)

    Bai, Lian; He, Siyao; Fruehwirth, John; Stein, Andreas; Cheng, Xiang; Macosko, Christopher

    Reduced graphene oxide (r-GO) is known to be effective in increasing the conductivity of cocontinuous polymer blends with a lower electrical percolation threshold. However, little is known regarding the localization and dynamics of r-GO along with morphology change during annealing. In this study, we develop a facile method to stabilize the polystyrene (PS)/polylactic acid (PLA) cocontinuous blends with r-GO jammed at interface. In this method, the non-functionalized GO is premixed with PLA via solvent method, and then reduced in-situ at 210oC to obtain a PLA/r-GO polymer composite. This composite is further mixed with PS via batch melt compounding. We observe the migration of r-GO from the PLA phase to the interface during annealing. The interfacial r-GO suppresses the coarsening of cocontinuous morphology and increases the conductivity of the filled polymer blend. Moreover, we systematically investigate the relationship between r-GO localization, rheological and conductivity change during annealing of r-GO filled PLA/PS blends. University of Minnesota Industrial Partnership for Research in Interfacial and Materials Engineering (IPRIME).

  11. Research of beam smoothing technologies using CPP, SSD, and PS

    NASA Astrophysics Data System (ADS)

    Zhang, Rui; Su, Jingqin; Hu, Dongxia; Li, Ping; Yuan, Haoyu; Zhou, Wei; Yuan, Qiang; Wang, Yuancheng; Tian, Xiaocheng; Xu, Dangpeng; Dong, Jun; Zhu, Qihua

    2015-02-01

    Precise physical experiments place strict requirements on target illumination uniformity in Inertial Confinement Fusion. To obtain a smoother focal spot and suppress transverse SBS in large aperture optics, Multi-FM smoothing by spectral dispersion (SSD) was studied combined with continuous phase plate (CPP) and polarization smoothing (PS). New ways of PS are being developed to improve the laser irradiation uniformity and solve LPI problems in indirect-drive laser fusion. The near field and far field properties of beams using polarization smoothing were studied and compared, including birefringent wedge and polarization control array. As more parameters can be manipulated in a combined beam smoothing scheme, quad beam smoothing was also studies. Simulation results indicate through adjusting dispersion directions of one-dimensional (1-D) SSD beams in a quad, two-dimensional SSD can be obtained. Experiments have been done on SG-III laser facility using CPP and Multi-FM SSD. The research provides some theoretical and experimental basis for the application of CPP, SSD and PS on high-power laser facilities.

  12. Effects of Preplasma in 10-ps Relativistic Laser Matter Interaction

    NASA Astrophysics Data System (ADS)

    Wei, M. S.; Stephens, R. B.; Peebles, J.; McGuffey, C.; Qiao, B.; Beg, F.; Sentoku, Y.; Link, A.; Chen, H.; McLean, H.; Theobald, W.; Haberberger, D.; Davies, A.

    2014-10-01

    Experiments were performed using the kJ 10-ps OMEGA EP laser to study the effect of preplasma on fast electron generation and energy coupling in relativistic laser plasma interaction (LPI) with a controlled preplasma at various scalelength created by a 1-ns UV laser. Targets were multilayered planar foil consisting of an Al substrate, a buried Cu layer and a thick conductive CH layer. Preplasma density profile and relativistic LPI generated fields were characterized using a 10-ps 4 ω optical probe (angular filter refractometry and polarimetry) together with radiography using a high-energy proton beam produced by the second kJ 10-ps EP beam. Fast electrons were diagnosed by measuring Cu K-shell fluorescence emission and bremsstrahlung radiation. Electron energy spectrum was monitored by a magnetic spectrometer. Preliminary results showed nonlinear interaction instabilities and a reduced electron temperature with increasing preplasma scalelength. Dynamics of the relativistic LPI and the resultant fast electron beam characteristics and energy coupling will be presented. Supported by the US DOE under DE-NA0002026 and DE-FC02-04ER54789.

  13. Expectation values of the e{sup +}PsH system

    SciTech Connect

    Zhang, J.-Y.; Mitroy, J.

    2007-07-15

    Close to converged energies and expectation values for e{sup +}PsH are computed using a ground-state wave function consisting of 1500 explicitly correlated Gaussians. The best estimate of the e{sup +}PsH{sup {infinity}} energy was -0.810 254 hartrees, which has a binding energy of 0.021 057 hartrees against dissociation into e{sup +}+PsH. The 2{gamma} annihilation rate was 2.7508x10{sup 9} s{sup -1}. Binding energies and annihilation rates are also given for the different finite-mass variants of e{sup +}PsH. Comparisons between expectation values for e{sup +}PsH and PsH provide compelling evidence that the e{sup +}PsH ground state can be regarded as consisting of a weakly bound positron orbiting the PsH ground state.

  14. [Dispute Resolutions].

    ERIC Educational Resources Information Center

    Hale, Claudia L.; Cooks, Leda M.

    1994-01-01

    Focusing on the teaching of alternative dispute resolutions at universities, Claudia L. Hale and Leda M. Cooks argue that mediation should be taught primarily as a communication process that involves the joint efforts of mediator and disputants. Teachers of mediation should begin by distinguishing mediation from other forms of dispute resolution,…

  15. Time resolution of a scintillating fiber detector

    NASA Astrophysics Data System (ADS)

    Horikawa, S.; Toeda, T.; Daito, I.; Doushita, N.; Hasegawa, T.; Horikawa, N.; Iwata, T.; Kibe, Y.; Matsuda, T.; Miyachi, Y.; Noboriguchi, K.; Takabayashi, N.; Tohyama, T.; Wakai, A.

    1999-07-01

    The performance of scintillating fiber detectors with 2 m long light guides was investigated for COMPASS experiment, using a 450 MeV/ c electron beam.Prototypes consisting of 0.5 mm diameter fibers (Kuraray SCSF-38 single-cladding) with the position-sensitive photomultipliers H6568 (Hamamatsu) were constructed for the test. The time resolution of σ˜430 ps was obtained with about 10 photoelectrons for the prototype of 10-layers structure.

  16. STIC3 - Silicon Photomultiplier Timing Chip with picosecond resolution

    NASA Astrophysics Data System (ADS)

    Stankova, Vera; Shen, Wei; Briggl, Konrad; Chen, Huangshan; Fischer, Peter; Gil, Alejandro; Harion, Tobias; Kiworra, Volker; Munwes, Yonathan; Ritzert, Michael; Schultz-Coulon, Hans-Christian

    2015-07-01

    The diagnostic of pancreas and prostate cancer is a challenging task due to the background noise coming from the closer organs. The EndoToFPET-US project aims to combine the synergy between metabolic and anatomical (ultrasound) image in order to improve the precision in the tumor localization. The goal of the project is to develop a Positron Emission Tomography (PET) system that provides a time-of-flight resolution of 200 ps FWHM for improving the signal to noise ratio and further to improve the medical image quality. In order to achieve this purpose an ASIC has been designed for very high timing resolution in time-of-flight (ToF) applications. In this paper we present the ASIC performance and the first characterization measurements with the 64-channels prototype version (STiC3). Measurements are performed with LYSO scintillator crystal and a Multi Pixel Photon Counter (MPPC). Measurements with the chip show an analog-front-end stage jitter of 35 ps for the first photo-electron equivalent charge and reach 18 ps for the third photo-electron. Coincidence time resolution (CTR) of 240 ps FWHM is measured with 3.1×3.1×15 mm3 LYSO crystal and 50 μm pixel pitch MPPC. Further optimization including the Time-to-Digital Converter (TDC) non-linearity corrections and setup fine tuning are ongoing for achieving the desired CTR of 200 ps FWHM.

  17. CYCLoPs: A Comprehensive Database Constructed from Automated Analysis of Protein Abundance and Subcellular Localization Patterns in Saccharomyces cerevisiae

    PubMed Central

    Koh, Judice L. Y.; Chong, Yolanda T.; Friesen, Helena; Moses, Alan; Boone, Charles; Andrews, Brenda J.; Moffat, Jason

    2015-01-01

    Changes in protein subcellular localization and abundance are central to biological regulation in eukaryotic cells. Quantitative measures of protein dynamics in vivo are therefore highly useful for elucidating specific regulatory pathways. Using a combinatorial approach of yeast synthetic genetic array technology, high-content screening, and machine learning classifiers, we developed an automated platform to characterize protein localization and abundance patterns from images of log phase cells from the open-reading frame−green fluorescent protein collection in the budding yeast, Saccharomyces cerevisiae. For each protein, we produced quantitative profiles of localization scores for 16 subcellular compartments at single-cell resolution to trace proteome-wide relocalization in conditions over time. We generated a collection of ∼300,000 micrographs, comprising more than 20 million cells and ∼9 billion quantitative measurements. The images depict the localization and abundance dynamics of more than 4000 proteins under two chemical treatments and in a selected mutant background. Here, we describe CYCLoPs (Collection of Yeast Cells Localization Patterns), a web database resource that provides a central platform for housing and analyzing our yeast proteome dynamics datasets at the single cell level. CYCLoPs version 1.0 is available at http://cyclops.ccbr.utoronto.ca. CYCLoPs will provide a valuable resource for the yeast and eukaryotic cell biology communities and will be updated as new experiments become available. PMID:26048563

  18. Communicating Knowing through Communities of Practice: Exploring Internal Communicative Processes and Differences among CoPs

    ERIC Educational Resources Information Center

    Iverson, Joel O.; McPhee, Robert D.

    2008-01-01

    Knowing is an enacted, communicated process that is difficult to observe, let alone manage, in organizations. Communities of practice (CoPs) offer a productive solution for improving knowledge and knowledge management, but the communicative processes that enact CoPs have not been explored, leaving CoPs as an organizational black box. This research…

  19. 7 CFR 1753.37 - Plans and specifications (P&S).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 11 2011-01-01 2011-01-01 false Plans and specifications (P&S). 1753.37 Section 1753... Installation of Central Office Equipment § 1753.37 Plans and specifications (P&S). (a) General. (1) Prior to the preparation of P&S, the borrower shall review with the GFR the current and future requirements...

  20. 7 CFR 1753.37 - Plans and specifications (P&S).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Plans and specifications (P&S). 1753.37 Section 1753... Installation of Central Office Equipment § 1753.37 Plans and specifications (P&S). (a) General. (1) Prior to the preparation of P&S, the borrower shall review with the GFR the current and future requirements...

  1. 7 CFR 1753.37 - Plans and specifications (P&S).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false Plans and specifications (P&S). 1753.37 Section 1753... Installation of Central Office Equipment § 1753.37 Plans and specifications (P&S). (a) General. (1) Prior to the preparation of P&S, the borrower shall review with the GFR the current and future requirements...

  2. 7 CFR 1753.37 - Plans and specifications (P&S).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false Plans and specifications (P&S). 1753.37 Section 1753... Installation of Central Office Equipment § 1753.37 Plans and specifications (P&S). (a) General. (1) Prior to the preparation of P&S, the borrower shall review with the GFR the current and future requirements...

  3. 7 CFR 1753.37 - Plans and specifications (P&S).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false Plans and specifications (P&S). 1753.37 Section 1753... Installation of Central Office Equipment § 1753.37 Plans and specifications (P&S). (a) General. (1) Prior to the preparation of P&S, the borrower shall review with the GFR the current and future requirements...

  4. A High-resolution TOF Detector _ A Possible Way to Compete with a RICH Detector

    SciTech Connect

    Va'vra, J; Ertley, C.; Leith, D.W.G.S.; Ratcliff, B.; Schwiening, J.; /SLAC

    2008-07-25

    Using two identical 64-pixel Burle/Photonis MCP-PMTs to provide start and stop signals, they have achieved a timing resolution of {sigma}{sub Single{_}detector} {approx} 7.2 ps for N{sub pe} {approx} 50 photoelectrons (N{sub pe}) with a laser diode providing a 1 mm spot on the MCP window. The limiting resolution achieved was {sigma}{sub Single{_}detector} {approx} 5.0 ps for N{sub pe} {approx} 180, for which they estimate the MCP-PMT contribution of {sigma}{sub MCP-PMT} {approx} 4.5 ps. The electronics contribution is estimated as {sigma}{sub Electrons} = 3.42 ps. These results suggest that an ultra-high resolution TOF detector may become a reality at future experiments one day.

  5. PsHint1, associated with the G-protein α subunit PsGPA1, is required for the chemotaxis and pathogenicity of Phytophthora sojae.

    PubMed

    Zhang, Xin; Zhai, Chunhua; Hua, Chenlei; Qiu, Min; Hao, Yujuan; Nie, Pingping; Ye, Wenwu; Wang, Yuanchao

    2016-02-01

    Zoospore chemotaxis to soybean isoflavones is essential in the early stages of infection by the oomycete pathogen Phytophthora sojae. Previously, we have identified a G-protein α subunit encoded by PsGPA1 which regulates the chemotaxis and pathogenicity of P. sojae. In the present study, we used affinity purification to identify PsGPA1-interacting proteins, including PsHint1, a histidine triad (HIT) domain-containing protein orthologous to human HIT nucleotide-binding protein 1 (HINT1). PsHint1 interacted with both the guanosine triphosphate (GTP)- and guanosine diphosphate (GDP)-bound forms of PsGPA1. An analysis of the gene-silenced transformants revealed that PsHint1 was involved in the chemotropic response of zoospores to the isoflavone daidzein. During interaction with a susceptible soybean cultivar, PsHint1-silenced transformants displayed significantly reduced infectious hyphal extension and caused a strong cell death in plants. In addition, the transformants displayed defective cyst germination, forming abnormal germ tubes that were highly branched and exhibited apical swelling. These results suggest that PsHint1 not only regulates chemotaxis by interacting with PsGPA1, but also participates in a Gα-independent pathway involved in the pathogenicity of P. sojae. PMID:25976113

  6. Quality control of the tribological coating PS212

    NASA Technical Reports Server (NTRS)

    Sliney, Harold E.; Dellacorte, Christopher; Deadmore, Daniel L.

    1989-01-01

    PS212 is a self-lubricating, composite coating that is applied by the plasma spray process. It is a functional lubricating coating from 25 C (or lower) to 900 C. The coating is prepared from a blend of three different powders with very dissimilar properties. Therefore, the final chemical composition and lubricating effectiveness of the coatings are very sensitive to the process variables used in their preparation. Defined here are the relevant variables. The process and analytical procedures that will result in satisfactory tribological coatings are discussed.

  7. Create and Publish a Hierarchical Progressive Survey (HiPS)

    NASA Astrophysics Data System (ADS)

    Fernique, P.; Boch, T.; Pineau, F.; Oberto, A.

    2014-05-01

    Since 2009, the CDS promotes a method for visualizing based on the HEALPix sky tessellation. This method, called “Hierarchical Progressive Survey" or HiPS, allows one to display a survey progressively. It is particularly suited for all-sky surveys or deep fields. This visualization method is now integrated in several applications, notably Aladin, the SiTools/MIZAR CNES framework, and the recent HTML5 “Aladin Lite". Also, more than one hundred surveys are already available in this view mode. In this article, we will present the progress concerning this method and its recent adaptation to the astronomical catalogs such as the GAIA simulation.

  8. Genetic transformation in the methanogen Methanococcus voltae PS

    NASA Technical Reports Server (NTRS)

    Bertani, G.; Baresi, L.

    1987-01-01

    Mutations causing requirements for histidine, purine, and vitamin B12 were obtained in strain PS of Methanococcus voltae (archaebacteria) upon irradiation with UV or gamma rays. The first two mutations were shown to revert at low frequencies and were used to demonstrate the occurrence of transformation with homologous, wild-type DNA. The transformation rates obtained for these presumably chromosomal markers were in the range of 2 to 100 transformants per microgram of DNA. Mutants resistant to 2-bromoethanesulfonate and to 5-methyl-DL-tryptophan were also isolated.

  9. Genetic transformation in the methanogen Methanococcus voltae PS

    SciTech Connect

    Bertani, G.; Baresi, L.

    1987-06-01

    Mutations causing requirements for histidine, purine, and vitamin B/sub 12/ were obtained in strain PS of Methanococcus voltae (archaebacteria) upon irradiation with UV or gamma rays. The first two mutations were shown to revert at low frequencies and were sued to demonstrate the occurrence of transformation with homologous, wild-type DNA. The transformation rates obtained for these presumably chromosomal markers were in the range of 2 to 100 transformants per ..mu..g of DNA. Mutants resistant to 2-bromoethanesulfonate and to 5-methyl-DL-tryptophan were also isolated.

  10. Parameter estimation in PS-InSAR deformation studies using integer least-squares techniques

    NASA Astrophysics Data System (ADS)

    Hanssen, R. F.; Ferretti, A.

    2002-12-01

    Interferometric synthetic aperture radar (InSAR) methods are increasingly used for measuring deformations of the earth's surface. Unfortunately, in many cases the problem of temporal decorrelation hampers successful measurements over longer time intervals. The permanent scatterers approach (PS-InSAR) for processing time series of SAR interferograms proves to be a good alternative by recognizing and analyzing single scatterers with a reliable phase behavior in time. Ambiguity resolution or phase unwrapping is the process of resolving the unknown cycle ambiguities in the radar data, and is one of the main problems in InSAR data analysis. In a single interferogram, the problem of phase unwrapping and parameter estimation is usually solved for in separate consecutive computations. It is often assumed that the final result of the phase unwrapping is a deterministic signal, used as input for the parameter estimation, e.g. elevation and deformation. As a result, errors in the ambiguity resolution are usually not propagated into the final results, which can lead to a serious underestimation of errors in the parameters and consequently in the geophysical models which use these parameters. In fact, however, the resolved phase ambiguities are stochastic as well, even though they are described with a probability mass function in stead of a probability density function. In this paper, the integer least-squares technique for integrated ambiguity resolution and parameter estimation is applied to PS-InSAR data analysis, using a three-step procedure. First, a standard least-squares adjustment is performed, assuming the ambiguities are float parameters, leading to the real-valued 'float'-solution. Second, the ambiguities are resolved using the float ambiguity estimates. Third, if the second step was successful, the integer estimates are used to correct the float solution estimate. It has been proved that the integer least-squares estimator is an optimal method in the sense that it

  11. TRPV-1-mediated elimination of residual iPS cells in bioengineered cardiac cell sheet tissues

    PubMed Central

    Matsuura, Katsuhisa; Seta, Hiroyoshi; Haraguchi, Yuji; Alsayegh, Khaled; Sekine, Hidekazu; Shimizu, Tatsuya; Hagiwara, Nobuhisa; Yamazaki, Kenji; Okano, Teruo

    2016-01-01

    The development of a suitable strategy for eliminating remaining undifferentiated cells is indispensable for the use of human-induced pluripotent stem (iPS) cell-derived cells in regenerative medicine. Here, we show for the first time that TRPV-1 activation through transient culture at 42 °C in combination with agonists is a simple and useful strategy to eliminate iPS cells from bioengineered cardiac cell sheet tissues. When human iPS cells were cultured at 42 °C, almost all cells disappeared by 48 hours through apoptosis. However, iPS cell-derived cardiomyocytes and fibroblasts maintained transcriptional and protein expression levels, and cardiac cell sheets were fabricated after reducing the temperature. TRPV-1 expression in iPS cells was upregulated at 42 °C, and iPS cell death at 42 °C was TRPV-1-dependent. Furthermore, TRPV-1 activation through thermal or agonist treatment eliminated iPS cells in cardiac tissues for a final concentration of 0.4% iPS cell contamination. These findings suggest that the difference in tolerance to TRPV-1 activation between iPS cells and iPS cell-derived cardiac cells could be exploited to eliminate remaining iPS cells in bioengineered cell sheet tissues, which will further reduce the risk of tumour formation. PMID:26888607

  12. Comparative study of myocytes from normal and mdx mice iPS cells.

    PubMed

    Chen, Fei; Cao, Jiqing; Liu, Qiang; Qin, Jie; Kong, Jie; Wang, Yanyun; Li, Yaqin; Geng, Jia; Li, Qiuling; Yang, Liqing; Xiang, Andy Peng; Zhang, Cheng

    2012-02-01

    Recently, induced pluripotent stem cells (iPS cells) have been derived from various techniques and show great potential for therapy of human diseases. Furthermore, the iPS technique can be used to provide cell models to explore pathological mechanisms of many human diseases in vitro, such as Duchenne muscular dystrophy (DMD), which is a severe recessive X-linked form of muscular dystrophy without effective treatment. In this study, we try to determine whether there are different characteristics of myocytes from mdx iPS cells and C57BL/10 iPS cells. Our results showed that both of mdx and C57BL/10 cells could be induced into iPS cells in vitro, whereas colony-forming ability of mdx iPS cells was much weaker than that of C57BL/10 iPS cells. Meanwhile, mdx iPS cells could be induced to differentiate into myocytes, whereas their differentiation efficiency was much lower than that of C57BL/10 iPS cells. And, the number of apoptotic cells in differentiated myocytes from mdx iPS cells was significantly higher than that from C57BL/10 iPS cells. More importantly, treatment of a pan-caspase inhibitor (Z-VAD) produced a significant decrease in apoptotic cells. This study might add some insight to the biology study of dystrophin gene. PMID:21976068

  13. Watching proteins function with 150-ps time-resolved X-ray crystallography

    NASA Astrophysics Data System (ADS)

    Anfinrud, Philip

    2007-03-01

    We have used time-resolved Laue crystallography to characterize ligand migration pathways and dynamics in wild-type and several mutant forms of myoglobin (Mb), a ligand-binding heme protein found in muscle tissue. In these pump-probe experiments, which were conducted on the ID09B time-resolved beamline at the European Synchrotron and Radiation Facility, a laser pulse photodissociates CO from an MbCO crystal and a suitably delayed X-ray pulse probes its structure via Laue diffraction. Single-site mutations in the vicinity of the heme pocket docking site were found to have a dramatic effect on ligand migration. To visualize this process, time-resolved electron density maps were stitched together into movies that unveil with <2-å spatial resolution and 150-ps time-resolution the correlated protein motions that accompany and/or mediate ligand migration. These studies help to illustrate at an atomic level relationships between protein structure, dynamics, and function.

  14. Ps-LAMBDA: Ambiguity success rate evaluation software for interferometric applications

    NASA Astrophysics Data System (ADS)

    Verhagen, Sandra; Li, Bofeng; Teunissen, Peter J. G.

    2013-04-01

    Integer ambiguity resolution is the process of estimating the unknown ambiguities of carrier-phase observables as integers. It applies to a wide range of interferometric applications of which Global Navigation Satellite System (GNSS) precise positioning is a prominent example. GNSS precise positioning can be accomplished anytime and anywhere on Earth, provided that the integer ambiguities of the very precise carrier-phase observables are successfully resolved. As wrongly resolved ambiguities may result in unacceptably large position errors, it is crucial that one is able to evaluate the probability of correct integer ambiguity estimation. This ambiguity success rate depends on the underlying mathematical model as well as on the integer estimation method used. In this contribution, we present the Matlab toolbox Ps-LAMBDA for the evaluation of the ambiguity success rates. It allows users to evaluate all available success rate bounds and approximations for different integer estimators. An assessment of the sharpness of the bounds and approximations is given as well. Furthermore, it is shown how the toolbox can be used to assess the integer ambiguity resolution performance for design and research purposes, so as to study for instance the impact of using different GNSS systems and/or different measurement scenarios.

  15. Protein structural dynamics in solution unveiled via 100-ps time-resolved x-ray scattering

    PubMed Central

    Anfinrud, Philip

    2010-01-01

    We have developed a time-resolved x-ray scattering diffractometer capable of probing structural dynamics of proteins in solution with 100-ps time resolution. This diffractometer, developed on the ID14B BioCARS (Consortium for Advanced Radiation Sources) beamline at the Advanced Photon Source, records x-ray scattering snapshots over a broad range of q spanning 0.02–2.5 Å-1, thereby providing simultaneous coverage of the small-angle x-ray scattering (SAXS) and wide-angle x-ray scattering (WAXS) regions. To demonstrate its capabilities, we have tracked structural changes in myoglobin as it undergoes a photolysis-induced transition from its carbon monoxy form (MbCO) to its deoxy form (Mb). Though the differences between the MbCO and Mb crystal structures are small (rmsd < 0.2 Å), time-resolved x-ray scattering differences recorded over 8 decades of time from 100 ps to 10 ms are rich in structure, illustrating the sensitivity of this technique. A strong, negative-going feature in the SAXS region appears promptly and corresponds to a sudden > 22 Å3 volume expansion of the protein. The ensuing conformational relaxation causes the protein to contract to a volume ∼2 Å3 larger than MbCO within ∼10 ns. On the timescale for CO escape from the primary docking site, another change in the SAXS/WAXS fingerprint appears, demonstrating sensitivity to the location of the dissociated CO. Global analysis of the SAXS/WAXS patterns recovered time-independent scattering fingerprints for four intermediate states of Mb. These SAXS/WAXS fingerprints provide stringent constraints for putative models of conformational states and structural transitions between them. PMID:20406909

  16. Protein structural dynamics in solution unveiled via 100-ps time-resolved x-ray scattering

    SciTech Connect

    Cho, Hyun Sun; Dashdorj, Naranbaatar; Schotte, Friedrich; Graber, Timothy; Henning, Robert; Anfinruda, Philip

    2010-04-21

    We have developed a time-resolved x-ray scattering diffractometer capable of probing structural dynamics of proteins in solution with 100-ps time resolution. This diffractometer, developed on the ID14B BioCARS (Consortium for Advanced Radiation Sources) beamline at the Advanced Photon Source, records x-ray scattering snapshots over a broad range of q spanning 0.02-2.5 {angstrom}{sup -1}, thereby providing simultaneous coverage of the small-angle x-ray scattering (SAXS) and wide-angle x-ray scattering (WAXS) regions. To demonstrate its capabilities, we have tracked structural changes in myoglobin as it undergoes a photolysis-induced transition from its carbon monoxy form (MbCO) to its deoxy form (Mb). Though the differences between the MbCO and Mb crystal structures are small (rmsd < 0.2 {angstrom}), time-resolved x-ray scattering differences recorded over 8 decades of time from 100 ps to 10 ms are rich in structure, illustrating the sensitivity of this technique. A strong, negative-going feature in the SAXS region appears promptly and corresponds to a sudden > 22 {angstrom}{sup 3} volume expansion of the protein. The ensuing conformational relaxation causes the protein to contract to a volume {approx}2 {angstrom}{sup 3} larger than MbCO within {approx}10 ns. On the timescale for CO escape from the primary docking site, another change in the SAXS/WAXS fingerprint appears, demonstrating sensitivity to the location of the dissociated CO. Global analysis of the SAXS/WAXS patterns recovered time-independent scattering fingerprints for four intermediate states of Mb. These SAXS/WAXS fingerprints provide stringent constraints for putative models of conformational states and structural transitions between them.

  17. [Features of Expression of the PsSst] and PsIgn1 Genes in Nodules of Pea (Pisum sativum L.) Symbiotic Mutants].

    PubMed

    Zhukova, V A; Rychagova, T S; Fedorina, Ya V; Pinaeva, A G; Andronova, E E; Borisova, A Yu; Tikhonovich, I A

    2016-04-01

    The sequences of the PsSst1 and PsIgn1 genes of pea (Pisum sativum L.) homologous to the symbiotic LjSST1 and LjIGN1 genes of Lotusjaponicus (Regel.) K. Larsen are determined. The expression level of PsSst1 and PsIgn1 genes is determined by real-time PCR in nodules of several symbiotic mutants and original lines of pea. Lines with increased (Sprint-2Fix⁻ (Pssym31)) and decreased (P61 (Pssym25)) expression level of both genes are revealed along with the lines characterized by changes in the expression level of only one of these genes. The revealed features of the PsSst1 and PsIgn1 expression allow us to expand the phenotypic characterization of pea symbiotic mutants. In addition, PsSst1 and PsIgn1 cDNA is sequenced in selected mutant lines, characterized by a decreased expression level of these genes in nodules, but no mutations are found. PMID:27529974

  18. Properties of Extruded PS-212 Type Self-Lubricating Materials

    NASA Technical Reports Server (NTRS)

    Waters, W. J.; Sliney, H. E.; Soltis, R. F.

    1993-01-01

    Research has been underway at the NASA Lewis Research Center since the 1960's to develop high temperature, self-lubricating materials. The bulk of the research has been done in-house by a team of researchers from the Materials Division. A series of self-lubricating solid material systems has been developed over the years. One of the most promising is the composite material system referred to as PS-212 or PM-212. This material is a powder metallurgy product composed of metal bonded chromium carbide and two solid lubricating materials known to be self-lubricating over a wide temperature range. NASA feels this material has a wide potential in industrial applications. Simplified processing of this material would enhance its commercial potential. Processing changes have the potential to reduce processing costs, but tribological and physical properties must not be adversely affected. Extrusion processing has been employed in this investigation as a consolidation process for PM-212/PS-212. It has been successful in that high density bars of EX-212 (extruded PM-212) can readily be fabricated. Friction and strength data indicate these properties have been maintained or improved over the P.M. version. A range of extrusion temperatures have been investigated and tensile, friction, wear, and microstructural data have been obtained. Results indicate extrusion temperatures are not critical from a densification standpoint, but other properties are temperature dependent.

  19. iPS cell technology: Future impact on renal care.

    PubMed

    Freedman, Benjamin S; Steinman, Theodore I

    2015-08-01

    iPS cells from patients with kidney disease are a new tool with the potential to impact the future of renal care. They can be used in the laboratory to model the pathophysiology of human kidney disease, and have the potential to establish a new area of immunocompatible, on-demand renal transplantation. Critical challenges remain before the full potential of these cells can be accurately assessed. We need to understand whether the derived cell types are mature and can replace kidney function(s). To what extent can iPS cells model kidney disease in the simplified environment of cell culture? Ultimately, successful integration of these cells as autograft therapies will require demonstration of safety and efficacy equal or superior to the existing gold standards of kidney allograft transplantation and dialysis. Specific educational and infrastructural changes will be necessary if these specialized technologies are to be adopted as an accepted modalities in clinical medicine. Given these barriers, the first fruit of these labors is likely to be improved understanding of pathophysiological pathways in human IPS cell disease models, followed by drug discovery and testing. These experiments will lead naturally to improvements in differentiation and experiments in animal models testing function. The time course to achieve the desired goals remains unknown, but the ultimate hope is that new, more effective and less expensive modalities for renal replacement therapy will occur in the foreseeable future. A new standard of care for patients is anticipated that addresses limitations of currently available treatments. PMID:26454909

  20. STS-52 PS MacLean, backup PS Tryggvason, and PI pose on JSC's CCT flight deck

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-52 Columbia, Orbiter Vehicle (OV) 102, Canadian Payload Specialist (PS) Steven G. MacLean (left) and backup Payload Specialist Bjarni V. Tryggvason (right) take a break from a camera training session in JSC's Crew Compartment Trainer (CCT). The two Canadian Space Agency (CSA) representatives pose on the CCT's aft flight deck with Canadian scientist David Zimick, the principal investigator (PI) for the materials experiment in low earth orbit (MELEO). MELEO is a component of the CANEX-2 experiment package, manifest to fly on the scheduled October 1992 STS-52 mission. The CCT is part of the shuttle Mockup and Integration Laboratory (MAIL) Bldg 9NE.

  1. The elite and stochastic model for iPS cell generation: multilineage-differentiating stress enduring (Muse) cells are readily reprogrammable into iPS cells.

    PubMed

    Wakao, Shohei; Kitada, Masaaki; Dezawa, Mari

    2013-01-01

    Induced pluripotent stem (iPS) cells have attracted a great deal of attention, although the mechanism by which they are generated is still not fully understood. Currently, two theories, the stochastic and elite models, have been proposed. Some reports provide theoretical support for the stochastic model. Other reports, however, support the elite model. For example, some human fibroblasts, such as Multilineage-differentiating stress enduring (Muse) cells, are reported to be pluripotent and a primary source of iPS cells. Thus, the mechanism of iPS cell generation continues to be debated. In this review, we discuss the properties of the original cell source, such as the components of the original populations and the potential of each population to become iPS cells, and further discuss the implications of the two theories for iPS cell research. PMID:22693162

  2. MicroRNA Expression Profiles of Human iPS Cells, Retinal Pigment Epithelium Derived From iPS, and Fetal Retinal Pigment Epithelium

    PubMed Central

    Greene, Whitney A.; Muñiz, Alberto.; Plamper, Mark L.; Kaini, Ramesh R.; Wang, Heuy-Ching

    2014-01-01

    The objective of this report is to describe the protocols for comparing the microRNA (miRNA) profiles of human induced-pluripotent stem (iPS) cells, retinal pigment epithelium (RPE) derived from human iPS cells (iPS-RPE), and fetal RPE. The protocols include collection of RNA for analysis by microarray, and the analysis of microarray data to identify miRNAs that are differentially expressed among three cell types. The methods for culture of iPS cells and fetal RPE are explained. The protocol used for differentiation of RPE from human iPS is also described. The RNA extraction technique we describe was selected to allow maximal recovery of very small RNA for use in a miRNA microarray. Finally, cellular pathway and network analysis of microarray data is explained. These techniques will facilitate the comparison of the miRNA profiles of three different cell types. PMID:24999033

  3. Laser-free RF-gun as a combined source of THz and ps-sub-ps X-rays

    DOE PAGESBeta

    Agustsson, R.; Boucher, S.; Finn, O.; Hartzell, J.; Ruelas, M.; Smirnov, A. V.; Storms, S.; Ning, Z.; Murokh, A.; Campese, T.; et al

    2015-01-01

    A coherent, mm-sub-mm-wave source driven by a RF electron gun is proposed for wide research applications as well as auxiliary inspection and screening, safe imaging, cancer diagnostics, surface defectoscopy, and enhanced time-domain spectroscopy. It allows generation of high peak and average THz-sub-THz radiation power provided by beam pre-bunching and chirping in the RF gun followed by microbunching in magnetic compressor, and resonant Cherenkov radiation of an essentially flat beam in a robust, ~inch-long, planar, mm-sub-mm gap structure. The proof-of-principle has been successfully demonstrated in Phase I on a 5 MeV beam of L-band thermionic injector of Idaho Accelerator Center. Themore » system can also deliver an intense, ps-sub-ps bursts of low-to-moderate dose of relativistic electrons and X-ray radiation produced by the same beam required for pulsed radiolysis as well as to enhance screening efficiency, throughput and safety.« less

  4. Laser-free RF-gun as a combined source of THz and ps-sub-ps X-rays

    SciTech Connect

    Agustsson, R.; Boucher, S.; Finn, O.; Hartzell, J.; Ruelas, M.; Smirnov, A. V.; Storms, S.; Ning, Z.; Murokh, A.; Campese, T.; Faillace, L.; Verma, A.; Kim, Y.; Buaphad, P.; Andrews, A.; Berls, B.; Eckman, C.; Folkman, K.; Knowles-Swingle, A.; O’Neill, C.; Smith, M.; Grandsaert, T.; van der Geer, B.; de Loos, M.; Berg, W. J.; Sereno, N. S.; Sun, Y.; Zholents, A. A.

    2015-01-01

    A coherent, mm-sub-mm-wave source driven by a RF electron gun is proposed for wide research applications as well as auxiliary inspection and screening, safe imaging, cancer diagnostics, surface defectoscopy, and enhanced time-domain spectroscopy. It allows generation of high peak and average THz-sub-THz radiation power provided by beam pre-bunching and chirping in the RF gun followed by microbunching in magnetic compressor, and resonant Cherenkov radiation of an essentially flat beam in a robust, ~inch-long, planar, mm-sub-mm gap structure. The proof-of-principle has been successfully demonstrated in Phase I on a 5 MeV beam of L-band thermionic injector of Idaho Accelerator Center. The system can also deliver an intense, ps-sub-ps bursts of low-to-moderate dose of relativistic electrons and X-ray radiation produced by the same beam required for pulsed radiolysis as well as to enhance screening efficiency, throughput and safety.

  5. Laser-Free RF-Gun as a Combined Source of Thz and Ps-Sub-Ps X-Rays

    NASA Astrophysics Data System (ADS)

    Agustsson, R.; Boucher, S.; Finn, O.; Hartzell, J.; Ruelas, M.; Smirnov, A. V.; Storms, S.; Ning, Z.; Murokh, A.; Campese, T.; Faillace, L.; Verma, A.; Kim, Y.; Buaphad, P.; Andrews, A.; Berls, B.; Eckman, C.; Folkman, K.; Knowles-Swingle, A.; O'Neill, C.; Smith, M.; Grandsaert, T.; van der Geer, B.; de Loos, M.; Berg, W. J.; Sereno, N. S.; Sun, Y.; Zholents, A. A.

    A coherent, mm-sub-mm-wave source driven by a RF electron gun is proposed for wide research applications as well as auxiliary inspection and screening, safe imaging, cancer diagnostics, surface defectoscopy, and enhanced time-domain spectroscopy. It allows generation of high peak and average THz-sub-THz radiation power provided by beam pre-bunching and chirping in the RF gun followed by microbunching in magnetic compressor, and resonant Cherenkov radiation of an essentially flat beam in a robust, ∼inch-long, planar, mm-sub-mm gap structure. The proof-of-principle has been successfully demonstrated in Phase I on a 5 MeV beam of L-band thermionic injector of Idaho Accelerator Center. The system can also deliver an intense, ps-sub-ps bursts of low-to-moderate dose of relativistic electrons and X-ray radiation produced by the same beam required for pulsed radiolysis as well as to enhance screening efficiency, throughput and safety.

  6. A high-resolution time-to-digital converter using a three-level resolution

    NASA Astrophysics Data System (ADS)

    Dehghani, Asma; Saneei, Mohsen; Mahani, Ali

    2016-08-01

    In this article, a three-level resolution Vernier delay line time-to-digital converter (TDC) was proposed. The proposed TDC core was based on the pseudo-differential digital architecture that made it insensitive to nMOS and pMOS transistor mismatches. It also employed a Vernier delay line (VDL) in conjunction with an asynchronous read-out circuitry. The time interval resolution was equal to the difference of delay between buffers of upper and lower chains. Then, via the extra chain included in the lower delay line, resolution was controlled and power consumption was reduced. This method led to high resolution and low power consumption. The measurement results of TDC showed a resolution of 4.5 ps, 12-bit output dynamic range, and integral nonlinearity of 1.5 least significant bits. This TDC achieved the consumption of 68.43 µW from 1.1-V supply.

  7. Performance Analysis of the ertPS Algorithm and Enhanced ertPS Algorithm for VoIP Services in IEEE 802.16e Systems

    NASA Astrophysics Data System (ADS)

    Kim, Bong Joo; Hwang, Gang Uk

    In this paper, we analyze the extended real-time Polling Service (ertPS) algorithm in IEEE 802.16e systems, which is designed to support Voice-over-Internet-Protocol (VoIP) services with data packets of various sizes and silence suppression. The analysis uses a two-dimensional Markov Chain, where the grant size and the voice packet state are considered, and an approximation formula for the total throughput in the ertPS algorithm is derived. Next, to improve the performance of the ertPS algorithm, we propose an enhanced uplink resource allocation algorithm, called the e2rtPS algorithm, for VoIP services in IEEE 802.16e systems. The e2rtPS algorithm considers the queue status information and tries to alleviate the queue congestion as soon as possible by using remaining network resources. Numerical results are provided to show the accuracy of the approximation analysis for the ertPS algorithm and to verify the effectiveness of the e2rtPS algorithm.

  8. Midinfrared Nonlinear Optical Thiophosphates from LiZnPS4 to AgZnPS4: A Combined Experimental and Theoretical Study.

    PubMed

    Zhou, Molin; Kang, Lei; Yao, Jiyong; Lin, Zheshuai; Wu, Yicheng; Chen, Chuangtian

    2016-04-18

    Our earlier theoretical calculation and preliminary experiment highlighted LiZnPS4 as a good mid-infrared (mid-IR) nonlinear optical (NLO) material. However, this compound suffers from problems including corrosion of the silica tubes, a pungent smell, deliquescence, and incongruent-melting behavior in the further single crystal growth and applications. In order to overcome these problems, herein, we investigate the analogues of LiZnPS4 and propose that AgZnPS4 would be a good candidate. The combination of experimental and theoretical study demonstrates that AgZnPS4 exhibits a much stronger NLO effect than that of LiZnPS4 despite the relatively smaller energy band gap. More importantly, AgZnPS4 melts congruently with a melting point as low as 534 °C, much lower than those of traditional IR NLO crystals, and is nondeliquescent with enough stability in the air. Such a good crystal growth habit and chemical stability enable AgZnPS4 to possess much better overall performance for the practical mid-IR NLO applications. PMID:27015097

  9. Comparing The Results Of Terrasar-X And Envisat Sar Images With Ps-InSAR Methods On Slow Motion Landslides: Koyulhisar, Turkey

    NASA Astrophysics Data System (ADS)

    Demirel, Mehmet; Poyraz, Fatih; Özgür Hastaoğlu, Kemal; Türk, Tarık; Tatar, Orhan; Birdal, Anıl Can

    2015-04-01

    In recent years, PS-InSAR method has been used widely on monitoring slow motion landslides. The motion amounts obtained by PS-InSAR method is avaliable only in LOS(line of sight) and it can't provide information about three dimensional motions. Nevertheless, motions caused by landslides are usually 3 dimensional and also they are not homogeneous. This is one of the biggest handicaps of monitoring landslides with SAR method. In this study, annual motion rates of the PS points that are located in Koyulhisar landslide region are obtained from differently resolutioned sar images of Envisat and Terrasar-x satellite's frames through PS-InSAR method and by using StaMPS software. Throughout the landslide region a profile has been established in North-South line, and the correlation of the results obtained from the sar images lining on this profile. All results are observed to have %80 correlation with each other. By means of these results a subsidence area has been found in the northern region and an uplifting area has been found in the southern region. Through this study, general information about the landslide mechanism has been obtained.

  10. Hormone interactions and regulation of Unifoliata, PsPK2, PsPIN1 and LE gene expression in pea (Pisum sativum) shoot tips.

    PubMed

    Bai, Fang; DeMason, Darleen A

    2006-07-01

    The Unifoliata (Uni) gene plays a major role in development of the compound leaf in pea, but its regulation is unknown. In this study, we examined the effects of plant hormones on the expression of Uni, PsPK2 (the gene for a pea homolog of Arabidopsis PID, a regulator of PIN1 targeting), PsPIN1 (the major gene for a putative auxin efflux carrier) and LE (a gibberellin biosynthesis gene, GA3ox), and also examined mutual hormonal regulation of these genes, in pea shoot tips, including a number of mutants. The Uni promoter possessed putative auxin and gibberellin response elements. The PsPIN1 mRNA levels were increased in afila, which replaces leaflets with branched tendrils; and reduced in tendrilless, which replaces tendrils with leaflets, compared with the wild type (WT). In contrast, mRNA levels of LE were increased in uni and tendrilless and decreased in afila compared with the WT. Uni, PsPK2 and PsPIN1 are positively regulated by gibberellin and auxin, and were induced to higher levels by simultaneous application of auxin and gibberellin. Auxin induction of Uni, PsPK2 and PsPIN1 did not require de novo protein synthesis. LE was positively regulated by auxin and cytokinin. In conclusion, these results support the hypothesis that auxin and gibberellin positively regulate Uni, which controls pea compound leaf development. Also, Uni, PsPIN1, PsPK2 and LE are expressed differentially in the leaf mutants, suggesting that mutual regulation by auxin and gibberellin promotes compound leaf development. PMID:16760220

  11. Coexistence of WiFi and WiMAX systems based on PS-request protocols.

    PubMed

    Kim, Jongwoo; Park, Suwon; Rhee, Seung Hyong; Choi, Yong-Hoon; Chung, Young-uk; Hwang, Ho Young

    2011-01-01

    We introduce both the coexistence zone within the WiMAX frame structure and a PS-Request protocol for the coexistence of WiFi and WiMAX systems sharing a frequency band. Because we know that the PS-Request protocol has drawbacks, we propose a revised PS-Request protocol to improve the performance. Two PS-Request protocols are based on the time division operation (TDO) of WiFi system and WiMAX system to avoid the mutual interference, and use the vestigial power management (PwrMgt) bit within the Frame Control field of the frames transmitted by a WiFi AP. The performance of the revised PS-Request protocol is evaluated by computer simulation, and compared to those of the cases without a coexistence protocol and to the original PS-Request protocol. PMID:22163721

  12. Coexistence of WiFi and WiMAX Systems Based on PS-Request Protocols†

    PubMed Central

    Kim, Jongwoo; Park, Suwon; Rhee, Seung Hyong; Choi, Yong-Hoon; Chung, Young-uk; Hwang, Ho Young

    2011-01-01

    We introduce both the coexistence zone within the WiMAX frame structure and a PS-Request protocol for the coexistence of WiFi and WiMAX systems sharing a frequency band. Because we know that the PS-Request protocol has drawbacks, we propose a revised PS-Request protocol to improve the performance. Two PS-Request protocols are based on the time division operation (TDO) of WiFi system and WiMAX system to avoid the mutual interference, and use the vestigial power management (PwrMgt) bit within the Frame Control field of the frames transmitted by a WiFi AP. The performance of the revised PS-Request protocol is evaluated by computer simulation, and compared to those of the cases without a coexistence protocol and to the original PS-Request protocol. PMID:22163721

  13. Calibration of PS09, PS10, and PS11 trans-Alaska pipeline system strong-motion instruments, with acceleration, velocity, and displacement records of the Denali fault earthquake, 03 November 2002

    USGS Publications Warehouse

    Evans, John R.; Jensen, E. Gray; Sell, Russell; Stephens, Christopher D.; Nyman, Douglas J.; Hamilton, Robert C.; Hager, William C.

    2006-01-01

    In September, 2003, the Alyeska Pipeline Service Company (APSC) and the U.S. Geological Survey (USGS) embarked on a joint effort to extract, test, and calibrate the accelerometers, amplifiers, and bandpass filters from the earthquake monitoring systems (EMS) at Pump Stations 09, 10, and 11 of the Trans-Alaska Pipeline System (TAPS). These were the three closest strong-motion seismographs to the Denali fault when it ruptured in the MW 7.9 earthquake of 03 November 2002 (22:12:41 UTC). The surface rupture is only 3.0 km from PS10 and 55.5 km from PS09 but PS11 is 124.2 km away from a small rupture splay and 126.9 km from the main trace. Here we briefly describe precision calibration results for all three instruments. Included with this report is a link to the seismograms reprocessed using these new calibrations: http://nsmp.wr.usgs.gov/data_sets/20021103_2212_taps.html Calibration information in this paper applies at the time of the Denali fault earthquake (03 November 2002), but not necessarily at other times because equipment at these stations is changed by APSC personnel at irregular intervals. In particular, the equipment at PS09, PS10, and PS11 was changed by our joint crew in September, 2003, so that we could perform these calibrations. The equipment stayed the same from at least the time of the earthquake until that retrieval, and these calibrations apply for that interval.

  14. Positional scanning substrate combinatorial library (PS-SCL) approach to define caspase substrate specificity.

    PubMed

    Poręba, Marcin; Szalek, Aleksandra; Kasperkiewicz, Paulina; Drąg, Marcin

    2014-01-01

    Positional scanning substrate combinatorial library (PS-SCL) is a powerful tool for studying substrate specificity of proteolytic enzymes. Here, we describe the protocol for analyzing S4-S2 pockets preferences of caspases using PS-SCL. Additionally, we describe procedures for the identification of optimal substrates sequence after PS-SCL, solid phase synthesis, and purification of selected fluorogenic substrates, as well as their kinetic analysis. PMID:24567093

  15. The New CERN PS control system overview and status

    NASA Astrophysics Data System (ADS)

    Perriollat, F.; Serre, C.

    1994-12-01

    The CERN PS control system is being completely rejuvenated. The existing system, whose design options were frozen in 1978, uses 16 bit minicomputers for process computers and for conventional consoles and services. These are being replaced by the agreed CERN Standard Architecture, using UNIX workstations as operator interface and VME based processors or PC frontends, under LynxOS. All CAMAC is essentially preserved. The project covers about five years and proceeds in steps of one year. Swicht over takes place in the annual shutdown, early in each year. No interference with the machine operation schedule is tolerated and this implies that no extra machine stops are planned for controls. The first two steps have been completed and operate to the complete satisfaction of the users; the LPI (Lep Preinjector) machines run since March 92 and the Proton Linac was started in March 93. The control system of the Lead Linac is being commissioned during 93 and 94. The third step of rejuvenation concerns the Booster machine and is under implementation now. The paper describes the architecture, the techniques used, the major components and the experience gained up to the conference time.

  16. A critical appraisal of NLO+PS matching methods

    NASA Astrophysics Data System (ADS)

    Höche, Stefan; Krauss, Frank; Schönherr, Marek; Siegert, Frank

    2012-09-01

    In this publication, uncertainties in and differences between the M C@NLO and P OWHEG methods for matching next-to-leading order QCD calculations with parton showers are discussed. Implementations of both algorithms within the event generator S HERPA and based on Catani-Seymour subtraction are employed to assess the impact on a representative selection of observables. In the case of M C@NLO a substantial simplification is achieved by using dipole subtraction terms to generate the first emission. A phase space restriction is employed, which allows to vary in a transparent way the amount of non-singular radiative corrections that are exponentiated. Effects on various observables are investigated, using the production of a Higgs boson in gluon fusion, with or without an associated jet, as a benchmark process. The case of H+jet production is presented for the first time in an NLO+PS matched simulation. Uncertainties due to scale choices and non-perturbative effects are explored in the production of W ± and Z bosons in association with a jet. Corresponding results are compared to data from the Tevatron and LHC experiments.

  17. A Critical Appraisal of NLO+PS Matching Methods

    SciTech Connect

    Hoeche, Stefan; Krauss, Frank; Schonherr, Marek; Siegert, Frank; /Freiburg U.

    2012-03-19

    In this publication, uncertainties in and differences between the MC{at}NLO and POWHEG methods for matching next-to-leading order QCD calculations with parton showers are discussed. Implementations of both algorithms within the event generator SHERPA are employed to assess the impact on a representative selection of observables. In the MC{at}NLO approach a phase space restriction has been added to subtraction and parton shower, which allows to vary in a transparent way the amount of non-singular radiative corrections that are exponentiated. Effects on various observables are investigated, using the production of a Higgs boson in gluon fusion, with or without an associated jet, as a benchmark process. The case of H+jet production is presented for the first time in an NLO+PS matched simulation. Uncertainties due to scale choices and non-perturbative effects are explored in the production of W{sup {+-}} and Z bosons in association with a jet. Corresponding results are compared to data from the Tevatron and LHC experiments.

  18. Multichannel low power time-to-digital converter card with 21 ps precision and full scale range up to 10 μs.

    PubMed

    Tamborini, D; Portaluppi, D; Villa, F; Tisa, S; Tosi, A

    2014-11-01

    We present a Time-to-Digital Converter (TDC) card with a compact form factor, suitable for multichannel timing instruments or for integration into more complex systems. The TDC Card provides 10 ps timing resolution over the whole measurement range, which is selectable from 160 ns up to 10 μs, reaching 21 ps rms precision, 1.25% LSB rms differential nonlinearity, up to 3 Mconversion/s with 400 mW power consumption. The I/O edge card connector provides timing data readout through either a parallel bus or a 100 MHz serial interface and further measurement information like input signal rate and valid conversion rate (typically useful for time-correlated single-photon counting application) through an independent serial link. PMID:25430129

  19. Multichannel low power time-to-digital converter card with 21 ps precision and full scale range up to 10 μs

    SciTech Connect

    Tamborini, D. Portaluppi, D.; Villa, F.; Tosi, A.; Tisa, S.

    2014-11-15

    We present a Time-to-Digital Converter (TDC) card with a compact form factor, suitable for multichannel timing instruments or for integration into more complex systems. The TDC Card provides 10 ps timing resolution over the whole measurement range, which is selectable from 160 ns up to 10 μs, reaching 21 ps rms precision, 1.25% LSB rms differential nonlinearity, up to 3 Mconversion/s with 400 mW power consumption. The I/O edge card connector provides timing data readout through either a parallel bus or a 100 MHz serial interface and further measurement information like input signal rate and valid conversion rate (typically useful for time-correlated single-photon counting application) through an independent serial link.

  20. Multichannel low power time-to-digital converter card with 21 ps precision and full scale range up to 10 μs

    NASA Astrophysics Data System (ADS)

    Tamborini, D.; Portaluppi, D.; Villa, F.; Tisa, S.; Tosi, A.

    2014-11-01

    We present a Time-to-Digital Converter (TDC) card with a compact form factor, suitable for multichannel timing instruments or for integration into more complex systems. The TDC Card provides 10 ps timing resolution over the whole measurement range, which is selectable from 160 ns up to 10 μs, reaching 21 ps rms precision, 1.25% LSB rms differential nonlinearity, up to 3 Mconversion/s with 400 mW power consumption. The I/O edge card connector provides timing data readout through either a parallel bus or a 100 MHz serial interface and further measurement information like input signal rate and valid conversion rate (typically useful for time-correlated single-photon counting application) through an independent serial link.

  1. Immunolocalization of PsNLEC-1, a lectin-like glycoprotein expressed in developing pea nodules.

    PubMed Central

    Dahiya, P; Kardailsky, I V; Brewin, N J

    1997-01-01

    The pea (Pisum sativum) nodule lectin gene PsNlec1 is a member of the legume lectin gene family that is strongly expressed in infected pea nodule tissue. A full-length cDNA sequence of PsNlec1 was expressed in Escherichia coli and a specific antiserum was generated from the purified protein. Immunoblotting of material from isolated symbiosomes revealed that the glycoprotein was present in two antigenic isoforms, PsNLEC-1A and PsNLEC-1B. The N-terminal sequence of isoform A showed homology to an eight-amino acid propeptide sequence previously identified from the cDNA sequence of isoform B. In nodule homogenates the antiserum recognized an additional fast-migrating band, PsNLEC-1C. Fractionation studies indicated that PsNLEC-1C was associated with a 100,000 g nodule membrane fraction, suggesting an association with cytoplasmic membrane or vesicles. Immunogold localization in pea nodule tissue sections demonstrated that the PsNLEC-1 antigen was present in the symbiosome compartment and also in the vacuole but revealed differences in distribution between infected host cells in different parts of the nodule. These data suggest that PsNLEC-1 is subject to posttranslational modification and that the various antigenic isoforms can be used to monitor membrane and vesicle targeting during symbiosome development. PMID:9414555

  2. PsANT, the adenine nucleotide translocase of Puccinia striiformis, promotes cell death and fungal growth.

    PubMed

    Tang, Chunlei; Wei, Jinping; Han, Qingmei; Liu, Rui; Duan, Xiaoyuan; Fu, Yanping; Huang, Xueling; Wang, Xiaojie; Kang, Zhensheng

    2015-01-01

    Adenine nucleotide translocase (ANT) is a constitutive mitochondrial component that is involved in ADP/ATP exchange and mitochondrion-mediated apoptosis in yeast and mammals. However, little is known about the function of ANT in pathogenic fungi. In this study, we identified an ANT gene of Puccinia striiformis f. sp. tritici (Pst), designated PsANT. The PsANT protein contains three typical conserved mitochondrion-carrier-protein (mito-carr) domains and shares more than 70% identity with its orthologs from other fungi, suggesting that ANT is conserved in fungi. Immuno-cytochemical localization confirmed the mitochondrial localization of PsANT in normal Pst hyphal cells or collapsed cells. Over-expression of PsANT indicated that PsANT promotes cell death in tobacco, wheat and fission yeast cells. Further study showed that the three mito-carr domains are all needed to induce cell death. qRT-PCR analyses revealed an in-planta induced expression of PsANT during infection. Knockdown of PsANT using a host-induced gene silencing system (HIGS) attenuated the growth and development of virulent Pst at the early infection stage but not enough to alter its pathogenicity. These results provide new insight into the function of PsANT in fungal cell death and growth and might be useful in the search for and design of novel disease control strategies. PMID:26058921

  3. PsANT, the adenine nucleotide translocase of Puccinia striiformis, promotes cell death and fungal growth

    PubMed Central

    Tang, Chunlei; Wei, Jinping; Han, Qingmei; Liu, Rui; Duan, Xiaoyuan; Fu, Yanping; Huang, Xueling; Wang, Xiaojie; Kang, Zhensheng

    2015-01-01

    Adenine nucleotide translocase (ANT) is a constitutive mitochondrial component that is involved in ADP/ATP exchange and mitochondrion-mediated apoptosis in yeast and mammals. However, little is known about the function of ANT in pathogenic fungi. In this study, we identified an ANT gene of Puccinia striiformis f. sp. tritici (Pst), designated PsANT. The PsANT protein contains three typical conserved mitochondrion-carrier-protein (mito-carr) domains and shares more than 70% identity with its orthologs from other fungi, suggesting that ANT is conserved in fungi. Immuno-cytochemical localization confirmed the mitochondrial localization of PsANT in normal Pst hyphal cells or collapsed cells. Over-expression of PsANT indicated that PsANT promotes cell death in tobacco, wheat and fission yeast cells. Further study showed that the three mito-carr domains are all needed to induce cell death. qRT-PCR analyses revealed an in-planta induced expression of PsANT during infection. Knockdown of PsANT using a host-induced gene silencing system (HIGS) attenuated the growth and development of virulent Pst at the early infection stage but not enough to alter its pathogenicity. These results provide new insight into the function of PsANT in fungal cell death and growth and might be useful in the search for and design of novel disease control strategies. PMID:26058921

  4. NASA PS400: A New Temperature Solid Lubricant Coating for High Temperature Wear Applications

    NASA Technical Reports Server (NTRS)

    DellaCorte, C.; Edmonds, B. J.

    2009-01-01

    A new solid lubricant coating, NASA PS400, has been developed for high temperature tribological applications. This plasma sprayed coating is a variant of the patented PS304 coating and has been formulated to provide higher density, smoother surface finish and better dimensional stability than PS304. PS400 is comprised of a nickel-molybdenum binder that provides strength, creep resistance and extreme oxidative and dimensional stability. Chromium oxide, silver and barium-calcium fluoride eutectic are added to the binder to form PS400.Tribological properties were evaluated with a pin-on-disk test rig in sliding contact to 650 C. Coating material samples were exposed to air, argon and vacuum at 760 C followed by cross section microscopic analysis to assess microstructure stability. Oil-Free microturbine engine hot section foil bearing tests were undertaken to assess PS400 s suitability for hot foil gas bearing applications. The preliminary results indicate that PS400 exhibits tribological characteristics comparable to the PS304 coating but with enhanced creep resistance and dimensional stability suitable for demanding, dynamic applications.

  5. 7 CFR 1753.26 - Plans and specifications (P&S).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... CFR part 1792, subpart C. (e) Two sets of the building plans and specifications shall be prepared and... 7 Agriculture 11 2010-01-01 2010-01-01 false Plans and specifications (P&S). 1753.26 Section 1753... Buildings § 1753.26 Plans and specifications (P&S). (a) For headquarters and commercial office...

  6. 7 CFR 1753.26 - Plans and specifications (P&S).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... CFR part 1792, subpart C. (e) Two sets of the building plans and specifications shall be prepared and... 7 Agriculture 11 2011-01-01 2011-01-01 false Plans and specifications (P&S). 1753.26 Section 1753... Buildings § 1753.26 Plans and specifications (P&S). (a) For headquarters and commercial office...

  7. SALT spectroscopic classification of PS15bjg as a type-Ia supernova

    NASA Astrophysics Data System (ADS)

    Jha, S. W.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Smith, K. W.; Wright, D.; Smartt, S. J.; Huber, M.; Chambers, K. C.; Flewelling, H.; Willman, M.; Primak, N.; Schultz, A.; Gibson, B.; Magnier, E.; Waters, C.; Tonry, J.; Wainscoat, R. J.; Colmenero, E. Romero

    2015-07-01

    We obtained SALT (+RSS) spectroscopy of PS15bjg on 2015 July 27.0 UT, covering the wavelength range 350-900 nm. Cross-correlation of the spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows PS15bjg to be a normal type-Ia supernova several days before maximum light.

  8. SALT spectroscopic classification of PS15bzz as a type-Ia supernova at maximum light

    NASA Astrophysics Data System (ADS)

    Jha, S. W.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Smith, K. W.; Wright, D.; Smartt, S. J.; Huber, M.; Chambers, K. C.; Flewelling, H.; Willman, M.; Primak, N.; Schultz, A.; Gibson, B.; Magnier, E.; Waters, C.; Tonry, J.; Wainscoat, R. J.; Miszalski, B.

    2015-09-01

    We obtained SALT (+RSS) spectroscopy of PS15bzz on 2015 Aug 16.9 UT, covering the wavelength range 360-820 nm. Cross-correlation of the spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows PS15bzz is a type-Ia supernova within a few days of maximum light.

  9. SALT spectroscopic classification of PS15atx as a type-Ia supernova

    NASA Astrophysics Data System (ADS)

    Jha, S. W.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Smith, K. W.; Wright, D.; Smartt, S. J.; Huber, M.; Chambers, K. C.; Flewelling, H.; Willman, M.; Primak, N.; Schultz, A.; Gibson, B.; Magnier, E.; Waters, C.; Tonry, J.; Wainscoat, R. J.; Depagne, E.

    2015-06-01

    We obtained SALT (+RSS) spectroscopy of PS15atx on 2015 June 20.8 UT, covering the wavelength range 400-950 nm. Cross-correlation of the spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows PS15atx to be a normal type-Ia supernova a few days before maximum light.

  10. 7 CFR 1753.26 - Plans and specifications (P&S).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... CFR part 1792, subpart C. (e) Two sets of the building plans and specifications shall be prepared and... 7 Agriculture 11 2014-01-01 2014-01-01 false Plans and specifications (P&S). 1753.26 Section 1753... Buildings § 1753.26 Plans and specifications (P&S). (a) For headquarters and commercial office...

  11. 7 CFR 1753.26 - Plans and specifications (P&S).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... CFR part 1792, subpart C. (e) Two sets of the building plans and specifications shall be prepared and... 7 Agriculture 11 2013-01-01 2013-01-01 false Plans and specifications (P&S). 1753.26 Section 1753... Buildings § 1753.26 Plans and specifications (P&S). (a) For headquarters and commercial office...

  12. 7 CFR 1753.26 - Plans and specifications (P&S).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... CFR part 1792, subpart C. (e) Two sets of the building plans and specifications shall be prepared and... 7 Agriculture 11 2012-01-01 2012-01-01 false Plans and specifications (P&S). 1753.26 Section 1753... Buildings § 1753.26 Plans and specifications (P&S). (a) For headquarters and commercial office...

  13. Preliminary Evaluation of PS300: A New Self-Lubricating High Temperature Composite Coating for Use to 800 C

    NASA Technical Reports Server (NTRS)

    Dellacorte, C.; Edmonds, B. J.

    1995-01-01

    This paper introduces PS300, a plasma sprayed, self-lubricating composite coating for use in sliding contacts at temperatures to 800 C. PS300 is a metal bonded chrome oxide coating with silver and BaF2/CaF2 eutectic solid lubricant additives. PS300 is similar to PS200, a chromium carbide based coating, which is currently being investigated for a variety of tribological applications. In pin-on-disk testing up to 650 C, PS300 exhibited comparable friction and wear properties to PS200. The PS300 matrix, which is predominantly chromium oxide rather than chromium carbide, does not require diamond grinding and polishes readily with silicon carbide abrasives greatly reducing manufacturing costs compared to PS200. It is anticipated that PS300 has potential for sliding bearing and seal applications in both aerospace and general industry.

  14. PICASSO: Lithosphere Structure in the Western Mediterranean from Ps Receiver Functions and Rayleigh Wave Tomography

    NASA Astrophysics Data System (ADS)

    Palomeras, I.; Thurner, S.; Levander, A.; Humphreys, E.; Miller, M. S.; Carbonell, R.; Gallart, J.

    2012-04-01

    The western Mediterranean is a diffuse plate boundary separating the African and Eurasian plates. Cenozoic deformation is centered on the Gibraltar arc and Alboran Sea, and occupies a wide area from the southern Iberian Massif in Spain to the Atlas Mountains in Morocco. We present a model of the lithospheric structure of this region derived from Rayleigh wave tomography and Ps receiver functions, using data from the PICASSO (Program to Investigate Convective Alboran Sea System Overturn) linear broadband array of ~100 seismographs. This array is deployed from central Spain to the Morocco-Algerian border. We complement these data with some of that recorded by IberArray, an areal broadband array, operated by the Spanish seismological community, covering the same region with a uniform 50 km x 50 km grid of stations. Rayleigh phase velocities have been measured from 20-167s period using the two-plane-wave method to remove complications due to multi-pathing, and finite-frequency kernels to improve lateral resolution. The phase velocities were inverted for 1D structure on a 0.25 by 0.25 degree grid. Ps receiver functions at 1Hz and 2Hz were calculated for the same area using water-level and time-domain iterative deconvolution, and were then CCP stacked. The Rayleigh wave shear velocity model, jointly interpreted with the discontinuity structure from the CCP stack, shows the first-order lithospheric structure, and the lithosphere-asthenosphere boundary (LAB). From north to south along the PICASSO profile: The lithosphere is ~120 km thick beneath the Iberian Massif, where it has the highest shear velocity, 4.45 km/s. To the south the lithosphere thins dramatically beneath the Betic Mountains to ~85 km, and then varies in thickness and decreases in velocity beneath the Alboran Sea and Gibraltar Arc. The thinnest lithosphere, ~60 km, is observed beneath the Rif mountains and Middle Atlas, with a low velocity feature (4.2 km/s) at ~60 km depth beneath a site of Late Cenozoic

  15. Grouping of Persistent Scatterers in high-resolution SAR data of urban scenes

    NASA Astrophysics Data System (ADS)

    Schunert, Alexander; Soergel, Uwe

    2012-09-01

    Persistent Scatterer Interferometry (PSI) is a technique to simultaneously estimate surface deformation and 3D structure from stacks of SAR images. It was proposed first about one decade ago to monitor preferably urban areas, where in general the highest numbers of PS are found. At that time no high-resolution satellite SAR data were available. Instead, for example, stacks of ERS imagery were used providing ground range resolution of about 25 m. In data of such kind only the strongest PS can be detected, which are usually caused by corner reflectors built by orthogonal building and road planes of considerable size, whereas smaller structures causing weaker ones signal are averaged by clutter or mutually interfere with others in the same resolution cell. Thus, if any, only a few or even just one single PS are found per building. The advent of a new senor generation of systems like TerraSAR-X and COSMO-Skymed in 2007 led to a significant improvement of spatial resolution of about one order of magnitude. This comes along with a dramatic rise of PS density: In some cases tens to hundreds are detected at large buildings, which offers the possibility to monitor even individual urban objects. In addition, especially at building façades the distribution of those PS is often quite regular. A reason for that is the usually rectilinear arrangement of façade structures inducing PS like windows or balconies. Those patterns contain a lot of information about the objects under investigation, which is mostly ignored in current PSI processing schemes. For example, consider a regular structure of windows on a certain façade of a multi-story building. Assuming the same kind of structure generates one single PS at each window, the phase centers of all scatterers caused by windows of each floor share the same height. This means, we may benefit from such kind of redundancy, for instance, to improve the height estimate by averaging over PS having the same elevation. In this work, we

  16. Retinoid Uptake, Processing, and Secretion in Human iPS-RPE Support the Visual Cycle

    PubMed Central

    Muñiz, Alberto; Greene, Whitney A.; Plamper, Mark L.; Choi, Jae Hyek; Johnson, Anthony J.; Tsin, Andrew T.; Wang, Heuy-Ching

    2014-01-01

    Purpose. Retinal pigmented epithelium derived from human induced pluripotent stem (iPS) cells (iPS-RPE) may be a source of cells for transplantation. For this reason, it is essential to determine the functional competence of iPS-RPE. One key role of the RPE is uptake and processing of retinoids via the visual cycle. The purpose of this study is to investigate the expression of visual cycle proteins and the functional ability of the visual cycle in iPS-RPE. Methods. iPS-RPE was derived from human iPS cells. Immunocytochemistry, RT-PCR, and Western blot analysis were used to detect expression of RPE genes lecithin-retinol acyl transferase (LRAT), RPE65, cellular retinaldehyde-binding protein (CRALBP), and pigment epithelium–derived factor (PEDF). All-trans retinol was delivered to cultured cells or whole cell homogenate to assess the ability of the iPS-RPE to process retinoids. Results. Cultured iPS-RPE expresses visual cycle genes LRAT, CRALBP, and RPE65. After incubation with all-trans retinol, iPS-RPE synthesized up to 2942 ± 551 pmol/mg protein all-trans retinyl esters. Inhibition of LRAT with N-ethylmaleimide (NEM) prevented retinyl ester synthesis. Significantly, after incubation with all-trans retinol, iPS-RPE released 188 ± 88 pmol/mg protein 11-cis retinaldehyde into the culture media. Conclusions. iPS-RPE develops classic RPE characteristics and maintains expression of visual cycle proteins. The results of this study confirm that iPS-RPE possesses the machinery to process retinoids for support of visual pigment regeneration. Inhibition of all-trans retinyl ester accumulation by NEM confirms LRAT is active in iPS-RPE. Finally, the detection of 11-cis retinaldehyde in the culture medium demonstrates the cells' ability to process retinoids through the visual cycle. This study demonstrates expression of key visual cycle machinery and complete visual cycle activity in iPS-RPE. PMID:24255038

  17. Elastomeric Capture Microparticles (ECmuPs) and Their use with Acoustophoresis to Perform Affinity Capture Assays

    NASA Astrophysics Data System (ADS)

    Cushing, Kevin Wallace

    This dissertation describes the development of elastomeric capture microparticles (ECmicroPs) and their use with acoustophoresis to perform affinity capture assays. ECμPs that function as negative acoustic contrast particles were developed by crosslinking emulsion-based droplets composed of commercially available silicone precursors followed by functionalization with avidin/biotin reagents. The size distribution of the ECμPs was very broad or narrow depending on the emulsion system that was used during the synthesis process. Elastomeric particles exhibited a very broad size distribution when a bulk-emulsion process was used; however, when microfluidic systems were utilized, their size distribution became comparatively narrow. The functionalization of elastomeric particles was accomplished by the non-specific adsorption of avidin protein followed by bovine serum albumin (BSA) blocking and bio-specific adsorption of a biotinylated-capture antibody. Polydisperse ECμPs were functionalized to bind prostate specific antigen (PSA) or IgG-phycoerythrin (PE) in aqueous media (buffer, plasma, blood); whereas monodisperse ECμPs were functionalized to bind a high density lipoprotein in the aqueous media. Polydisperse ECμPs functionalized to bind PSA in a physiological buffer (PBS pH 7.4) demonstrated nanomolar detection using flow cytometry analysis; whereas ECμPs functionalized to bind IgG-PE demonstrated picomolar detection in 10% porcine plasma. ECμPs have a specific density of ~1.03 and are more compressible than their surrounding aqueous media; which allowed the ECμPs to exhibit negative acoustic contrast properties under an ultrasonic acoustic standing wave field. The negative acoustic contrast property of ECμPs was advantageously utilized in an IgG-PE assay conducted in 0.1% whole porcine blood. The ligand-bound ECμPs suspended in the diluted blood sample were flowed through an acoustofluidic device where the application of an ultrasonic acoustic standing wave

  18. TG/FTIR analysis on co-pyrolysis behavior of PE, PVC and PS.

    PubMed

    Wu, Jingli; Chen, Tianju; Luo, Xitao; Han, Dezhi; Wang, Zhiqi; Wu, Jinhu

    2014-03-01

    The pyrolysis and co-pyrolysis behaviors of polyethylene (PE), polystyrene (PS) and polyvinyl chloride (PVC) under N2 atmosphere were analyzed by Thermal gravimetric/Fourier transform infrared (TG/FTIR). The volatile products were analyzed to investigate the interaction of the plastic blends during the thermal decomposition process. The TGA results showed that the thermal stability increased followed by PVC, PS and PE. The pyrolysis process of PE was enhanced when mixed with PS. However, PS was postponed when mixed with PVC. As for PE and PVC, mutual block was happened when mixed together. The FTIR results showed that the free radical of the decomposition could combine into a stable compound. When PE mixed with PVC or PS, large amount of unsaturated hydrocarbon groups existed in products while the content of alkynes was decreased. The methyl (-CH3) and methylene (-CH2-) bonds were disappeared while PVC mixed with PE. PMID:24411064

  19. Study of mechanical properties of polyvinyl chloride (PVC) and polystyrene (PS) polymers and their blends

    NASA Astrophysics Data System (ADS)

    Agarwal, Shalini; Saxena, N. S.; Agrawal, R.; Saraswat, Vibhav K.

    2013-06-01

    Presented work is an effort to observe the variation in mechanical properties of two thermoplastic materials PVC, PS and their blends. PVC and PS are taken in the ratio of 100:0, 70:30, 50:50, and 0:100. Mixing of PVC and PS is carried out by solution casting method using tetra hydro furan as solvent. Dynamical mechanical analyzer (DMA) is used to study mechanical properties. The storage modulus, loss modulus and mechanical loss factor (tan δ) are determined with temperature. The pallets of pure PS, PVC and their blends are scanned over a temperature range from room to 140 °C. The variation of modulus, tan δ of pure PVC & pure PS and their blends with temperature were studied. The observed variation in modulus and tan δ could be accounted for their thermal behavior and compositions.

  20. Tribology and Microstructure of PS212 with a Cr2O3 Seal Coat

    NASA Technical Reports Server (NTRS)

    Sliney, Harold E.; Benoy, Patricia A.; Korenyi-Both, Andras; Dellacorte, Christopher

    1994-01-01

    PS212 is a plasma sprayed metal bonding chrome carbide coating with solid lubricant additives which has lubricating properties at temperatures up to about 900 deg C. The coating is diamond ground to achieve an acceptable tribological surface. But, as with many plasma spray coatings, PS212 is not fully-dense. In this study, a chromium oxide base seal coating is used in an attempt to seal any porosity that is open to the surface of the PS212 coating, and to study the effect of the sealant on the tribological properties of PS212. The results indicate that the seal coating reduces friction and wear when it is applied and then diamond ground leaving a thin layer of seal coating which fills in the surface pits of the PS212 coating.

  1. Formation of positron-atom bound states in collisions between Rydberg Ps and neutral atoms

    NASA Astrophysics Data System (ADS)

    Swann, A. R.; Cassidy, D. B.; Deller, A.; Gribakin, G. F.

    2016-05-01

    Predicted 20 years ago, positron binding to neutral atoms has not yet been observed experimentally. A scheme is proposed to detect positron-atom bound states by colliding Rydberg positronium (Ps) with neutral atoms. Estimates of the charge-transfer reaction cross section are obtained using the first Born approximation for a selection of neutral atom targets and a wide range of incident Ps energies and principal quantum numbers. We also estimate the corresponding Ps ionization cross section. The accuracy of the calculations is tested by comparison with earlier predictions for charge transfer in Ps collisions with hydrogen and antihydrogen. We describe an existing Rydberg Ps beam suitable for producing positron-atom bound states and estimate signal rates based on the calculated cross sections and realistic experimental parameters. We conclude that the proposed methodology is capable of producing such states and of testing theoretical predictions of their binding energies.

  2. iPS cell technologies: significance and applications to CNS regeneration and disease

    PubMed Central

    2014-01-01

    In 2006, we demonstrated that mature somatic cells can be reprogrammed to a pluripotent state by gene transfer, generating induced pluripotent stem (iPS) cells. Since that time, there has been an enormous increase in interest regarding the application of iPS cell technologies to medical science, in particular for regenerative medicine and human disease modeling. In this review article, we outline the current status of applications of iPS technology to cell therapies (particularly for spinal cord injury), as well as neurological disease-specific iPS cell research (particularly for Parkinson’s disease and Alzheimer’s disease). Finally, future directions of iPS cell research are discussed including a) development of an accurate assay system for disease-associated phenotypes, b) demonstration of causative relationships between genotypes and phenotypes by genome editing, c) application to sporadic and common diseases, and d) application to preemptive medicine. PMID:24685317

  3. iPS cell technology-based research for the treatment of diabetic nephropathy.

    PubMed

    Osafune, Kenji

    2012-09-01

    Regenerative medicine strategies using induced pluripotent stem (iPS) cells are among the candidate approaches to treat diabetic nephropathy caused by type 1 diabetes. Cell transplantation therapy and disease modeling with patient-derived iPS cells should be examined for diabetic renal disease. Considerable work already has been performed with regard to the generation of renal lineage cells from mouse embryonic stem cells, however, few reports have described research with human embryonic stem cells or iPS cells. Further elucidation of the mechanisms of kidney development and establishing the method for directed differentiation from human iPS cells into renal lineage cells will be required for the development of iPS cell technology-based treatment for diabetic nephropathy. PMID:23062989

  4. Measurement of Time Resolution of the Mu2e LYSO Calorimeter Prototype

    SciTech Connect

    Atanov, N.

    2015-09-16

    In this paper we present the time resolution measurements of the LutetiumYttrium Oxyorthosilicate (LYSO) calorimeter prototype for the Mu2e experiment. The measurements have been performed using the e- beam of the Beam Test Facility (BTF) in Frascati, Italy in the energy range from 100 to 400 MeV. The calorimeter prototype consisted of twenty five 30x30x130 mm3, LYSO crystals read out by 10x10 mm2 Hamamatsu Avalanche Photodiodes (APDs). The energy dependence of the measured time resolution can be parametrized as σt(E) = a/pE/GeV⊕b, with the stochastic and constant terms a = (51±1) ps and b = (14 ± 1) ps, respectively. This corresponds to the time resolution of (162 ± 3) ps at 100 MeV.

  5. Measurement of time resolution of the Mu2e LYSO calorimeter prototype

    NASA Astrophysics Data System (ADS)

    Atanov, N.; Baranov, V.; Colao, F.; Cordelli, M.; Corradi, G.; Dané, E.; Davydov, Yu. I.; Flood, K.; Giovannella, S.; Glagolev, V.; Happacher, F.; Hitlin, D. G.; Martini, M.; Miscetti, S.; Miyashita, T.; Morescalchi, L.; Pezzullo, G.; Saputi, A.; Sarra, I.; Soleti, S. R.; Tassielli, G.; Tereshchenko, V.

    2016-03-01

    In this paper we present the time resolution measurements of the Lutetium-Yttrium Oxyorthosilicate (LYSO) calorimeter prototype for the Mu2e experiment. The measurements have been performed using the e- beam of the Beam Test Facility (BTF) in Frascati, Italy in the energy range from 100 to 400 MeV. The calorimeter prototype consisted of twenty five 30 × 30 × 130mm3, LYSO crystals read out by 10 × 10mm2 Hamamatsu Avalanche Photodiodes (APDs). The energy dependence of the measured time resolution can be parametrized as σt(E) = a /√{ E / GeV } ⊕ b, with the stochastic and constant terms a =(51 ± 1) ps and b =(10 ± 4) ps, respectively. This corresponds to the time resolution of (162 ± 4) ps at 100 MeV.

  6. Asiago classification of PS15mb and ASASSN-15ed

    NASA Astrophysics Data System (ADS)

    Noebauer, U.; Ishida, E.; Taubenberger, S.; Tomasella, L.; Ochner, P.; Benetti, S.; Cappellaro, E.; Elias-Rosa, N.; Pastorello, A.; Tartaglia, L.; Terreran, G.; Turatto, M.

    2015-03-01

    The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic observation of the following transients. The observations were performed with the Asiago 1.82 m Copernico Telescope (+AFOSC; range 340-820 nm; resolution 1.4 nm).

  7. Land Cover Change Community-based Processing and Analysis System (LC-ComPS): Lessons Learned from Technology Infusion

    NASA Astrophysics Data System (ADS)

    Masek, J.; Rao, A.; Gao, F.; Davis, P.; Jackson, G.; Huang, C.; Weinstein, B.

    2008-12-01

    The Land Cover Change Community-based Processing and Analysis System (LC-ComPS) combines grid technology, existing science modules, and dynamic workflows to enable users to complete advanced land data processing on data available from local and distributed archives. Changes in land cover represent a direct link between human activities and the global environment, and in turn affect Earth's climate. Thus characterizing land cover change has become a major goal for Earth observation science. Many science algorithms exist to generate new products (e.g., surface reflectance, change detection) used to study land cover change. The overall objective of the LC-ComPS is to release a set of tools and services to the land science community that can be implemented as a flexible LC-ComPS to produce surface reflectance and land-cover change information with ground resolution on the order of Landsat-class instruments. This package includes software modules for pre-processing Landsat-type satellite imagery (calibration, atmospheric correction, orthorectification, precision registration, BRDF correction) for performing land-cover change analysis and includes pre-built workflow chains to automatically generate surface reflectance and land-cover change products based on user input. In order to meet the project objectives, the team created the infrastructure (i.e., client-server system with graphical and machine interfaces) to expand the use of these existing science algorithm capabilities in a community with distributed, large data archives and processing centers. Because of the distributed nature of the user community, grid technology was chosen to unite the dispersed community resources. At that time, grid computing was not used consistently and operationally within the Earth science research community. Therefore, there was a learning curve to configure and implement the underlying public key infrastructure (PKI) interfaces, required for the user authentication, secure file

  8. The Ames dwarf mutation attenuates Alzheimer's disease phenotype of APP/PS1 mice.

    PubMed

    Puig, Kendra L; Kulas, Joshua A; Franklin, Whitney; Rakoczy, Sharlene G; Taglialatela, Giulio; Brown-Borg, Holly M; Combs, Colin K

    2016-04-01

    APP/PS1 double transgenic mice expressing human mutant amyloid precursor protein (APP) and presenilin-1 (PS1) demonstrate robust brain amyloid beta (Aβ) peptide containing plaque deposition, increased markers of oxidative stress, behavioral dysfunction, and proinflammatory gliosis. On the other hand, lack of growth hormone, prolactin, and thyroid-stimulating hormone due to a recessive mutation in the Prop 1 gene (Prop1df) in Ames dwarf mice results in a phenotype characterized by potentiated antioxidant mechanisms, improved learning and memory, and significantly increased longevity in homozygous mice. Based on this, we hypothesized that a similar hormone deficiency might attenuate disease changes in the brains of APP/PS1 mice. To test this idea, APP/PS1 mice were crossed to the Ames dwarf mouse line. APP/PS1, wild-type, df/+, df/df, df/+/APP/PS1, and df/df/APP/PS1 mice were compared at 6 months of age through behavioral testing and assessing amyloid burden, reactive gliosis, and brain cytokine levels. df/df mice demonstrated lower brain growth hormone and insulin-like growth factor 1 concentrations. This correlated with decreased astrogliosis and microgliosis in the df/df/APP/PS1 mice and, surprisingly, reduced Aβ plaque deposition and Aβ 1-40 and Aβ 1-42 concentrations. The df/df/APP/PS1 mice also demonstrated significantly elevated brain levels of multiple cytokines in spite of the attenuated gliosis. These data indicate that the df/df/APP/PS1 line is a unique resource in which to study aging and resistance to disease and suggest that the affected pituitary hormones may have a role in regulating disease progression. PMID:26973101

  9. Intron-exon organization of the active human protein S gene PS. alpha. and its pseudogene PS. beta. : Duplication and silencing during primate evolution

    SciTech Connect

    Ploos van Amstel, H.; Reitsma, P.H.; van der Logt, C.P.; Bertina, R.M. )

    1990-08-28

    The human protein S locus on chromosome 3 consists of two protein S genes, PS{alpha} and PS{beta}. Here the authors report the cloning and characterization of both genes. Fifteen exons of the PS{alpha} gene were identified that together code for protein S mRNA as derived from the reported protein S cDNAs. Analysis by primer extension of liver protein S mRNA, however, reveals the presence of two mRNA forms that differ in the length of their 5{prime}-noncoding region. Both transcripts contain a 5{prime}-noncoding region longer than found in the protein S cDNAs. The two products may arise from alternative splicing of an additional intron in this region or from the usage of two start sites for transcription. The intron-exon organization of the PS{alpha} gene fully supports the hypothesis that the protein S gene is the product of an evolutional assembling process in which gene modules coding for structural/functional protein units also found in other coagulation proteins have been put upstream of the ancestral gene of a steroid hormone binding protein. The PS{beta} gene is identified as a pseudogene. It contains a large variety of detrimental aberrations, viz., the absence of exon I, a splice site mutation, three stop codons, and a frame shift mutation. Overall the two genes PS{alpha} and PS{beta} show between their exonic sequences 96.5% homology. Southern analysis of primate DNA showed that the duplication of the ancestral protein S gene has occurred after the branching of the orangutan from the African apes. A nonsense mutation that is present in the pseudogene of man also could be identified in one of the two protein S genes of both chimpanzee and gorilla. This implicates that silencing of one of the two protein S genes must have taken place before the divergence of the three African apes.

  10. How to squeeze high quantum efficiency and high time resolution out of a SPAD

    NASA Technical Reports Server (NTRS)

    Lacaita, A.; Zappa, F.; Cova, Sergio; Ripamonti, Giancarlo; Spinelli, A.

    1993-01-01

    We address the issue whether Single-Photon Avalanche Diodes (SPADs) can be suitably designed to achieve a trade-off between quantum efficiency and time resolution performance. We briefly recall the physical mechanisms setting the time resolution of avalanche photodiodes operated in single-photon counting, and we give some criteria for the design of SPADs with a quantum efficiency better than l0 percent at 1064 nm together with a time resolution below 50 ps rms.

  11. Optical diagnostic suite (schlieren, interferometry, and grid image refractometry) on OMEGA EP using a 10-ps, 263-nm probe beam

    SciTech Connect

    Froula, D. H.; Boni, R.; Bedzyk, M.; Craxton, R. S.; Ehrne, F.; Ivancic, S.; Jungquist, R.; Shoup, M. J.; Theobald, W.; Weiner, D.; Kugland, N. L.; Rushford, M. C.

    2012-10-15

    A 10-ps, 263-nm (4{omega}) laser is being built to probe plasmas produced on the OMEGA EP [J. H. Kelly, L. J. Waxer, V. Bagnoud, I. A. Begishev, J. Bromage, B. E. Kruschwitz, T. E. Kessler, S. J. Loucks, D. N. Maywar, R. L. McCrory et al., J. Phys. IV France 133, 75-80 (2006)]. A suite of optical diagnostics (schlieren, interferometry, and grid image refractometry) has been designed to diagnose and characterize a wide variety of plasmas. Light scattered by the probe beam is collected by an f/4 catadioptric telescope and a transport system is designed to image with a near-diffraction-limited resolution ({approx}1 -{mu}m full width at half maximum) over a 5-mm field of view to a diagnostic table. The transport system provides a contrast greater than 1 : 10{sup 4} with respect to all wavelengths outside of the 263 {+-} 2 nm measurement range.

  12. Optical diagnostic suite (schlieren, interferometry, and grid image refractometry) on OMEGA EP using a 10-ps, 263-nm probe beam.

    PubMed

    Froula, D H; Boni, R; Bedzyk, M; Craxton, R S; Ehrne, F; Ivancic, S; Jungquist, R; Shoup, M J; Theobald, W; Weiner, D; Kugland, N L; Rushford, M C

    2012-10-01

    A 10-ps, 263-nm (4ω) laser is being built to probe plasmas produced on the OMEGA EP [J. H. Kelly, L. J. Waxer, V. Bagnoud, I. A. Begishev, J. Bromage, B. E. Kruschwitz, T. E. Kessler, S. J. Loucks, D. N. Maywar, R. L. McCrory et al., J. Phys. IV France 133, 75-80 (2006)]. A suite of optical diagnostics (schlieren, interferometry, and grid image refractometry) has been designed to diagnose and characterize a wide variety of plasmas. Light scattered by the probe beam is collected by an f/4 catadioptric telescope and a transport system is designed to image with a near-diffraction-limited resolution (~1 - μm full width at half maximum) over a 5-mm field of view to a diagnostic table. The transport system provides a contrast greater than 1 : 10(4) with respect to all wavelengths outside of the 263 ± 2 nm measurement range. PMID:23127030

  13. iPS cells to model CDKL5-related disorders

    PubMed Central

    Amenduni, Mariangela; De Filippis, Roberta; Cheung, Aaron Y L; Disciglio, Vittoria; Epistolato, Maria Carmela; Ariani, Francesca; Mari, Francesca; Mencarelli, Maria Antonietta; Hayek, Youssef; Renieri, Alessandra; Ellis, James; Meloni, Ilaria

    2011-01-01

    Rett syndrome (RTT) is a progressive neurologic disorder representing one of the most common causes of mental retardation in females. To date mutations in three genes have been associated with this condition. Classic RTT is caused by mutations in the MECP2 gene, whereas variants can be due to mutations in either MECP2 or FOXG1 or CDKL5. Mutations in CDKL5 have been identified both in females with the early onset seizure variant of RTT and in males with X-linked epileptic encephalopathy. CDKL5 is a kinase protein highly expressed in neurons, but its exact function inside the cell is unknown. To address this issue we established a human cellular model for CDKL5-related disease using the recently developed technology of induced pluripotent stem cells (iPSCs). iPSCs can be expanded indefinitely and differentiated in vitro into many different cell types, including neurons. These features make them the ideal tool to study disease mechanisms directly on the primarily affected neuronal cells. We derived iPSCs from fibroblasts of one female with p.Q347X and one male with p.T288I mutation, affected by early onset seizure variant and X-linked epileptic encephalopathy, respectively. We demonstrated that female CDKL5-mutated iPSCs maintain X-chromosome inactivation and clones express either the mutant CDKL5 allele or the wild-type allele that serve as an ideal experimental control. Array CGH indicates normal isogenic molecular karyotypes without detection of de novo CNVs in the CDKL5-mutated iPSCs. Furthermore, the iPS cells can be differentiated into neurons and are thus suitable to model disease pathogenesis in vitro. PMID:21750574

  14. Genital warts in Burmeister's porpoises: characterization of Phocoena spinipinnis papillomavirus type 1 (PsPV-1) and evidence for a second, distantly related PsPV.

    PubMed

    Van Bressem, Marie-Françoise; Cassonnet, Patricia; Rector, Annabel; Desaintes, Christian; Van Waerebeek, Koen; Alfaro-Shigueto, Joanna; Van Ranst, Marc; Orth, Gérard

    2007-07-01

    We identified sequences from two distantly related papillomaviruses in genital warts from two Burmeister's porpoises, including a PV antigen-positive specimen, and characterized Phocoena spinipinnis papillomavirus type 1 (PsPV-1). The PsPV-1 genome comprises 7879 nt and presents unusual features. It lacks an E7, an E8 and a bona fide E5 open reading frame (ORF) and has a large E6 ORF. PsPV-1 L1 ORF showed the highest percentage of nucleotide identity (54-55 %) with human papillomavirus type 5, bovine papillomavirus type 3 (BPV-3) and Tursiops truncatus papillomavirus type 2 (TtPV-2). This warrants the classification of PsPV-1 as the prototype of the genus Omikronpapillomavirus. PsPV-1 clustered with TtPV-2 in the E6 and E1E2 phylogenetic trees and with TtPV-2 and BPV-3 in the L2L1 tree. This supports the hypothesis that PV evolution may not be monophyletic across all genes. PMID:17554024

  15. Integration-Free iPS Cells Engineered Using Human Artificial Chromosome Vectors

    PubMed Central

    Hiratsuka, Masaharu; Uno, Narumi; Ueda, Kana; Kurosaki, Hajime; Imaoka, Natsuko; Kazuki, Kanako; Ueno, Etsuya; Akakura, Yutaro; Katoh, Motonobu; Osaki, Mitsuhiko; Kazuki, Yasuhiro; Nakagawa, Masato; Yamanaka, Shinya; Oshimura, Mitsuo

    2011-01-01

    Human artificial chromosomes (HACs) have unique characteristics as gene-delivery vectors, including episomal transmission and transfer of multiple, large transgenes. Here, we demonstrate the advantages of HAC vectors for reprogramming mouse embryonic fibroblasts (MEFs) into induced pluripotent stem (iPS) cells. Two HAC vectors (iHAC1 and iHAC2) were constructed. Both carried four reprogramming factors, and iHAC2 also encoded a p53-knockdown cassette. iHAC1 partially reprogrammed MEFs, and iHAC2 efficiently reprogrammed MEFs. Global gene expression patterns showed that the iHACs, unlike other vectors, generated relatively uniform iPS cells. Under non-selecting conditions, we established iHAC-free iPS cells by isolating cells that spontaneously lost iHAC2. Analyses of pluripotent markers, teratomas and chimeras confirmed that these iHAC-free iPS cells were pluripotent. Moreover, iHAC-free iPS cells with a re-introduced HAC encoding Herpes Simplex virus thymidine kinase were eliminated by ganciclovir treatment, indicating that the HAC safeguard system functioned in iPS cells. Thus, the HAC vector could generate uniform, integration-free iPS cells with a built-in safeguard system. PMID:21998730

  16. Reprogramming in vivo produces teratomas and iPS cells with totipotency features.

    PubMed

    Abad, María; Mosteiro, Lluc; Pantoja, Cristina; Cañamero, Marta; Rayon, Teresa; Ors, Inmaculada; Graña, Osvaldo; Megías, Diego; Domínguez, Orlando; Martínez, Dolores; Manzanares, Miguel; Ortega, Sagrario; Serrano, Manuel

    2013-10-17

    Reprogramming of adult cells to generate induced pluripotent stem cells (iPS cells) has opened new therapeutic opportunities; however, little is known about the possibility of in vivo reprogramming within tissues. Here we show that transitory induction of the four factors Oct4, Sox2, Klf4 and c-Myc in mice results in teratomas emerging from multiple organs, implying that full reprogramming can occur in vivo. Analyses of the stomach, intestine, pancreas and kidney reveal groups of dedifferentiated cells that express the pluripotency marker NANOG, indicative of in situ reprogramming. By bone marrow transplantation, we demonstrate that haematopoietic cells can also be reprogrammed in vivo. Notably, reprogrammable mice present circulating iPS cells in the blood and, at the transcriptome level, these in vivo generated iPS cells are closer to embryonic stem cells (ES cells) than standard in vitro generated iPS cells. Moreover, in vivo iPS cells efficiently contribute to the trophectoderm lineage, suggesting that they achieve a more plastic or primitive state than ES cells. Finally, intraperitoneal injection of in vivo iPS cells generates embryo-like structures that express embryonic and extraembryonic markers. We conclude that reprogramming in vivo is feasible and confers totipotency features absent in standard iPS or ES cells. These discoveries could be relevant for future applications of reprogramming in regenerative medicine. PMID:24025773

  17. Characterization of cucurbita maxima phloem serpin-1 (CmPS-1). A developmentally regulated elastase inhibitor.

    PubMed

    Yoo, B C; Aoki, K; Xiang, Y; Campbell, L R; Hull, R J; Xoconostle-Cázares, B; Monzer, J; Lee, J Y; Ullman, D E; Lucas, W J

    2000-11-10

    We report on the molecular, biochemical, and functional characterization of Cucurbita maxima phloem serpin-1 (CmPS-1), a novel 42-kDa serine proteinase inhibitor that is developmentally regulated and has anti-elastase properties. CmPS-1 was purified to near homogeneity from C. maxima (pumpkin) phloem exudate and, based on microsequence analysis, the cDNA encoding CmPS-1 was cloned. The association rate constant (k(a)) of phloem-purified and recombinant His(6)-tagged CmPS-1 for elastase was 3.5 +/- 1.6 x 10(5) and 2.7 +/- 0.4 x 10(5) m(-)(1) s(-)(1), respectively. The fraction of complex-forming CmPS-1, X(inh), was estimated at 79%. CmPS-1 displayed no detectable inhibitory properties against chymotrypsin, trypsin, or thrombin. The elastase cleavage sites within the reactive center loop of CmPS-1 were determined to be Val(347)-Gly(348) and Val(350)-Ser(351) with a 3:2 molar ratio. In vivo feeding assays conducted with the piercing-sucking aphid, Myzus persicae, established a close correlation between the developmentally regulated increase in CmPS-1 within the phloem sap and the reduced ability of these insects to survive and reproduce on C. maxima. However, in vitro feeding experiments, using purified phloem CmPS-1, failed to demonstrate a direct effect on aphid survival. Likely roles of this novel phloem serpin in defense against insects/pathogens are discussed. PMID:10960478

  18. Delayed Amyloid Plaque Deposition and Behavioral Deficits in Outcrossed AβPP/PS1 Mice

    PubMed Central

    Couch, Brian A.; Kerrisk, Meghan E.; Kaufman, Adam C.; Nygaard, Haakon B.; Strittmatter, Stephen M.; Koleske, Anthony J.

    2012-01-01

    Alzheimer’s disease (AD) is a progressive neurodegenerative dementia characterized by amyloid plaque accumulation, synapse/dendrite loss, and cognitive impairment. Transgenic mice expressing mutant forms of amyloid-β precursor protein (AβPP) and presenilin-1 (PS1) recapitulate several aspects of this disease and provide a useful model system for studying elements of AD progression. AβPP/PS1 mice have been previously shown to exhibit behavioral deficits and amyloid plaque deposition between 4–9 months of age. We crossed AβPP/PS1 animals with mice of a mixed genetic background (C57BL/6 × 129/SvJ) and investigated the development of AD-like features in the resulting outcrossed mice. The onset of memory-based behavioral impairment is delayed considerably in outcrossed AβPP/PS1 mice relative to inbred mice on a C57BL/6 background. While inbred AβPP/PS1 mice develop deficits in radial-arm water maze performance and novel object recognition as early as 8 months, outcrossed AβPP/PS1 mice do not display defects until 18 months. Within the forebrain, we find that inbred AβPP/PS1 mice have significantly higher amyloid plaque burden at 12 months than outcrossed AβPP/PS1 mice of the same age. Surprisingly, inbred AβPP/PS1 mice at 8 months have low plaque burden suggesting that plaque burden alone cannot explain the accompanying behavioral deficits. Analysis of AβPP processing revealed that elevated levels of soluble Aβ correlate with the degree of behavioral impairment in both strains. Taken together, these findings suggest that animal behavior, amyloid plaque deposition, and AβPP processing are sensitive to genetic differences between mouse strains. PMID:23047754

  19. Time resolution of a 1-inch cylindrical CeBr{sub 3} crystal at {sup 60}Co energies

    SciTech Connect

    Vedia, V.; Fraile, L. M.; Olaizola, B.; Paziy, V.; Picado, E.; Udias, J. M.; Mach, H.

    2013-06-10

    We have measured time resolutions of a cylindrical CeBr{sub 3} scintillator of 1-inch in height and 1-inch in diameter coupled to two different fast photomultiplier tubes, Hamamatsu R9779 and Photonis XP20D0, as a function of applied high voltages and different settings of a Constant Fraction Discriminator ORTEC 935. The time resolution was measured using a time-delayed coincidence set-up involving a fast reference detector. The best result of 119(2) ps at {sup 60}Co energies was obtained for the CeBr{sub 3} crystal coupled to the Hamamatsu PMT. This result is comparable to the resolution of 107 ps reported for a LaBr{sub 3}(Ce) crystal of the same size. For the coupling of the CeBr{sub 3} scintillator to the Photonis PMT we got the time resolution of 146(2) ps.

  20. Resonant-photoemission identification of the valence states of NiPS 3

    NASA Astrophysics Data System (ADS)

    Kelly, M. K.; Daniels, R. R.; Margaritondo, G.; Lévy, F.

    1984-04-01

    We monitored the resonant behavior of the Ni d satellite peaks in the valence band photoemission spectra of NiPS 3 at photon energies immediately below and immediately above the Ni3p threshold. The observed resonance gives an unequivocal identification of the satellite peaks and of the corresponding main Ni d features. The study of the electronic structure of this material and of the related compounds FePS 3 and HgPS 3 was extended to unoccupied states by means of partial-yield synchrotron-radiation photoemission spectroscopy.

  1. Generation of iPS Cells from Human Peripheral Blood Mononuclear Cells Using Episomal Vectors.

    PubMed

    Su, Ruijun Jeanna; Neises, Amanda; Zhang, Xiao-Bing

    2016-01-01

    Peripheral blood is the easy-to-access, minimally invasive, and the most abundant cell source to use for cell reprogramming. The episomal vector is among the best approaches for generating integration-free induced pluripotent stem (iPS) cells due to its simplicity and affordability. Here we describe the detailed protocol for the efficient generation of integration-free iPS cells from peripheral blood mononuclear cells. With this optimized protocol, one can readily generate hundreds of iPS cell colonies from 1 ml of peripheral blood. PMID:25403468

  2. Virus-induced gene silencing of PEAM4 affects floral morphology by altering the expression pattern of PsSOC1a and PsPVP in pea.

    PubMed

    Chen, Zhe-Hao; Jia, Fei-Fei; Hu, Jiang-Qin; Pang, Ji-Liang; Xu, Lei; Wang, Li-Lin

    2014-01-15

    pea-MADS4 (PEAM4) regulates floral morphology in Pisum sativum L., however, its molecular mechanisms still remain unclear. Virus-induced gene silencing (VIGS) is a recently developed reverse genetic approach that facilities an easier and more rapid study of gene functions. In this study, the PEAM4 gene was effectively silenced by VIGS using a pea early browning virus (PEBV) in wild type pea JI992. The infected plants showed abnormal phenotypes, as the floral organs, especially the sepals and petals changed in both size and shape, which made the corolla less closed. The petals changed in morphology and internal symmetry with, the stamens reduced and carpel dehisced. Larger sepals and longer tendrils with small cauline leaves appeared, with some sepals turning into bracts, and secondary inflorescences with fused floral organs were formed, indicating a flower-to-inflorescence change. The infected plants also displayed a delayed and prolonged flowering time. The PEAM4-VIGS plants with altered floral morphology were similar to the pim (proliferating inflorescence meristem) mutant and also mimicked the phenotypes of ap1 mutants in Arabidopsis. The expression pattern of the homologous genes PsSOC1a and PsSVP, which were involved in flowering time and florescence morphological control downstream of PEAM4, were analyzed by real-time RT-PCR and mRNA in situ hybridization. PsSOC1a and PsSVP were ectopically expressed and enhanced in the floral meristems from PEAM4-silenced plants. Our data suggests that PEAM4 may have a similar molecular mechanism as AtAP1, which inhibits the expression of PsSOC1a and PsSVP in the floral meristem from the early stages of flower development. As such, in this way PEAM4 plays a crucial role in maintaining floral organ identity and flower development in pea. PMID:24331430

  3. Time- and energy-resolution measurements of BaF2, BC-418, LYSO and CeBr3 scintillators

    NASA Astrophysics Data System (ADS)

    Ackermann, Ulrich; Egger, Werner; Sperr, Peter; Dollinger, Günther

    2015-06-01

    We have investigated the time and energy resolution (TTiming, ∆E/E) of four different scintillator materials BaF2, BC-418, LYSO and CeBr3 at a gamma energy of 511 keV in views of their possible usage for time, energy and position resolution for positron annihilation experiments. The shape of each scintillator was a cylinder with a diameter of 25 mm and a height of 10 mm readout by a Photonis XP2020/URQ photomultiplier tube. The best single time resolution was determined for each photomultiplier-scintillator setup in a three step optimization process. The optimized single time resolutions (FWHM) for BaF2, BC-418, LYSO and CeBr3 were 119 ps, 117 ps, 269 ps and 127 ps, respectively. We measured the energy resolution of the photomultiplier-scintillator setups which show a photopeak in the energy spectrum. The energy resolutions ∆E/E of BaF2, LYSO and CeBr3 were 9.8%, 9.7% and 5.4%, respectively. The overall most promising material for measuring simultaneously time, energy and position resolution for positron annihilation experiments seems to be CeBr3 due to its very good time and energy resolution characteristics.

  4. A cosmic ray test platform based on high time resolution MRPC technology

    NASA Astrophysics Data System (ADS)

    Chen, Tian-Xiang; Li, Cheng; Sun, Yong-Jie; Chen, Hong-Fang; Shao, Ming; Tang, Ze-Bo; Yang, Rong-Xing; Zhou, Yi; Zhang, Yi-Fei

    2015-05-01

    In order to test the performance of detector prototypes in a laboratory environment, we design and build a large area (90 cm×52 cm) test platform for cosmic rays based on a well-designed Multi-gap Resistive Plate Chamber (MRPC) with excellent time resolution and a high detection efficiency for minimum ionizing particles. The time resolution of the MRPC module used is tested to be ∼80 ps, and the position resolution along the strip is ∼5 mm, while the position resolution perpendicular to the strip is ∼12.7 mm. The platform constructed by four MRPC modules can be used for tracking cosmic rays with a spatial resolution of ∼6.3 mm, and provide a reference time ∼40 ps. Supported by National Natural Science Foundation of China (11275196), and Strategic Priority Research Program of the Chinese Academy of Sciences (XDA03010100)

  5. Advanced Photon Counting Imaging Detectors with 100ps Timing for Astronomical and Space Sensing Applications

    NASA Astrophysics Data System (ADS)

    Siegmund, O.; Vallerga, J.; Welsh, B.; Rabin, M.; Bloch, J.

    In recent years EAG has implemented a variety of high-resolution, large format, photon-counting MCP detectors in space instrumentation for satellite FUSE, GALEX, IMAGE, SOHO, HST-COS, rocket, and shuttle payloads. Our scheme of choice has been delay line readouts encoding photon event position centroids, by determination of the difference in arrival time of the event charge at the two ends of a distributed resistive-capacitive (RC) delay line. Our most commonly used delay line configuration is the cross delay line (XDL). In its simplest form the delay-line encoding electronics consists of a fast amplifier for each end of the delay line, followed by time-to-digital converters (TDC's). We have achieved resolutions of < 25 μm in tests over 65 mm x 65 mm (3k x3k resolution elements) with excellent linearity. Using high speed TDC's, we have been able to encode event positions for random photon rates of ~1 MHz, while time tagging events using the MCP output signal to better than 100 ps. The unique ability to record photon X,Y,T high fidelity information has advantages over "frame driven" recording devices for some important applications. For example we have built open face and sealed tube cross delay line detectors used for biological fluorescence lifetime imaging, observation of flare stars, orbital satellites and space debris with the GALEX satellite, and time resolved imaging of the Crab Pulsar with a telescope as small as 1m. Although microchannel plate delay line detectors meet many of the imaging and timing demands of various applications, they have limitations. The relatively high gain (107) reduces lifetime and local counting rate, and the fixed delay (10's of ns) makes multiple simultaneous event recording problematic. To overcome these limitations we have begun development of cross strip readout anodes for microchannel plate detectors. The cross strip (XS) anode is a coarse (~0.5 mm) multi-layer metal and ceramic pattern of crossed fingers on an alumina

  6. Observation of coupled vortex gyrations by 70-ps-time and 20-nm-space- resolved full-field magnetic transmission soft x-ray microscopy

    SciTech Connect

    Jung, Hyunsung; Yu, Young-Sang; Lee, Ki-Suk; Im, Mi-Young; Fischer, Peter; Bocklage, Lars; Vogel, Andreas; Bolte, Markus; Meier, Guido; Kim, Sang-Koog

    2010-09-01

    We employed time-and space-resolved full-field magnetic transmission soft x-ray microscopy to observe vortex-core gyrations in a pair of dipolar-coupled vortex-state Permalloy (Ni{sub 80}Fe{sub 20}) disks. The 70 ps temporal and 20 nm spatial resolution of the microscope enabled us to simultaneously measure vortex gyrations in both disks and to resolve the phases and amplitudes of both vortex-core positions. We observed their correlation for a specific vortex-state configuration. This work provides a robust and direct method of studying vortex gyrations in dipolar-coupled vortex oscillators.

  7. Direct generation of 2-ps blue pulses from gain-switched InGaN VCSEL assessed by up-conversion technique

    PubMed Central

    Asahara, Akifumi; Chen, Shaoqiang; Ito, Takashi; Yoshita, Masahiro; Liu, Wenjie; Zhang, Baoping; Suemoto, Tohru; Akiyama, Hidefumi

    2014-01-01

    Ultra-short pulses in blue region generated from compact and low-cost semiconductor lasers have attracted much attention for a wide variety of applications. Nitride-based vertical-cavity surface-emitting lasers (VCSELs), having intrinsic high material gain and short cavities, favor the generation of ultra-short blue pulses via a simple gain-switching technique. In this study, we fabricated a single-mode InGaN VCSEL consisting of 10-period InGaN/GaN quantum wells (QWs). The output pulses were evaluated accurately with an up-conversion measurement system having time resolution of 0.12 ps. We demonstrated that ultra-short blue pulses, as short as 2.2 ps at 3.4 K and 4.0 ps at room temperature, were generated from the gain-switched InGaN VCSEL via impulsive optical pumping, without any post-processing. The gain-switched pulses we obtained should greatly promote the development of ultra-short blue pulse generation. In addition, this successful assessment demonstrates the up-conversion technique's usefulness for characterizing ultra-short blue pulses from semiconductor lasers. PMID:25236162

  8. Direct generation of 2-ps blue pulses from gain-switched InGaN VCSEL assessed by up-conversion technique.

    PubMed

    Asahara, Akifumi; Chen, Shaoqiang; Ito, Takashi; Yoshita, Masahiro; Liu, Wenjie; Zhang, Baoping; Suemoto, Tohru; Akiyama, Hidefumi

    2014-01-01

    Ultra-short pulses in blue region generated from compact and low-cost semiconductor lasers have attracted much attention for a wide variety of applications. Nitride-based vertical-cavity surface-emitting lasers (VCSELs), having intrinsic high material gain and short cavities, favor the generation of ultra-short blue pulses via a simple gain-switching technique. In this study, we fabricated a single-mode InGaN VCSEL consisting of 10-period InGaN/GaN quantum wells (QWs). The output pulses were evaluated accurately with an up-conversion measurement system having time resolution of 0.12 ps. We demonstrated that ultra-short blue pulses, as short as 2.2 ps at 3.4 K and 4.0 ps at room temperature, were generated from the gain-switched InGaN VCSEL via impulsive optical pumping, without any post-processing. The gain-switched pulses we obtained should greatly promote the development of ultra-short blue pulse generation. In addition, this successful assessment demonstrates the up-conversion technique's usefulness for characterizing ultra-short blue pulses from semiconductor lasers. PMID:25236162

  9. Probe-pulse optimization for nonresonant suppression in hybrid fs/ps coherent anti-Stokes Raman scattering at high temperature.

    PubMed

    Miller, Joseph D; Slipchenko, Mikhail N; Meyer, Terrence R

    2011-07-01

    Hybrid femtosecond/picosecond coherent anti-Stokes Raman scattering (fs/ps CARS) offers accurate thermometry at kHz rates for combustion diagnostics. In high-temperature flames, selection of probe-pulse characteristics is key to simultaneously optimizing signal-to-nonresonant-background ratio, signal strength, and spectral resolution. We demonstrate a simple method for enhancing signal-to-nonresonant-background ratio by using a narrowband Lorentzian filter to generate a time-asymmetric probe pulse with full-width-half-maximum (FWHM) pulse width of only 240 fs. This allows detection within just 310 fs after the Raman excitation for eliminating nonresonant background while retaining 45% of the resonant signal at 2000 K. The narrow linewidth is comparable to that of a time-symmetric sinc2 probe pulse with a pulse width of ~2.4 ps generated with a conventional 4-f pulse shaper. This allows nonresonant-background-free, frequency-domain vibrational spectroscopy at high temperature, as verified using comparisons to a time-dependent theoretical fs/ps CARS model. PMID:21747487

  10. Room temperature light emission from the low-dimensional semiconductors AZrPS{sub 6} ( A = K, Rb, Cs).

    SciTech Connect

    Banerjee, S.; Szarko, J. M.; Yuhas, B. D.; Malliakas, C. D.; Chen, L. X.; Kanatzidis, M. G.

    2010-03-29

    The new semiconducting thiophosphate compounds KZrPS{sub 6}, RbZrPS{sub 6}, and CsZrPS{sub 6} exhibit red light emission at room temperature. The materials have longer photoluminescence lifetimes than most of the inorganic chalcogenide semiconductors. They can be solution processed into thin films for potential device fabrication.

  11. Time resolution studies using digital constant fraction discrimination

    NASA Astrophysics Data System (ADS)

    Fallu-Labruyere, A.; Tan, H.; Hennig, W.; Warburton, W. K.

    2007-08-01

    Digital Pulse Processing (DPP) modules are being increasingly considered to replace modular analog electronics in medium-scale nuclear physics experiments (100-1000s of channels). One major area remains, however, where it has not been convincingly demonstrated that DPP modules are competitive with their analog predecessors—time-of-arrival measurement. While analog discriminators and time-to-amplitude converters can readily achieve coincidence time resolutions in the 300-500 ps range with suitably fast scintillators and Photomultiplier Tubes (PMTs), this capability has not been widely demonstrated with DPPs. Some concern has been expressed, in fact, that such time resolutions are attainable with the 10 ns sampling times that are presently commonly available. In this work, we present time-coincidence measurements taken using a commercially available DPP (the Pixie-4 from XIA LLC) directly coupled to pairs of fast PMTs mated with either LSO or LaBr 3 scintillator crystals and excited by 22Na γ-ray emissions. Our results, 886 ps for LSO and 576 ps for LaBr 3, while not matching the best literature results using analog electronics, are already well below 1 ns and fully adequate for a wide variety of experiments. These results are shown not to be limited by the DPPs themselves, which achieved 57 ps time resolution using a pulser, but are degraded in part both by the somewhat limited number of photoelectrons we collected and by a sub-optimum choice of PMT. Analysis further suggests that increasing the sampling speed would further improve performance. We therefore conclude that DPP time-of-arrival resolution is already adequate to supplant analog processing in many applications and that further improvements could be achieved with only modest efforts.

  12. Chemically defined conditions for human iPS cell derivation and culture

    PubMed Central

    Chen, Guokai; Gulbranson, Daniel R.; Hou, Zhonggang; Bolin, Jennifer M.; Ruotti, Victor; Probasco, Mitchell D.; Smuga-Otto, Kimberly; Howden, Sara E.; Diol, Nicole R.; Propson, Nicholas E.; Wagner, Ryan; Lee, Garrett O.; Antosiewicz-Bourget, Jessica; Teng, Joyce M. C.; Thomson, James A.

    2011-01-01

    We reexamine the individual components for human ES and iPS cell culture, and formulate a cell culture system in which all protein reagents for liquid media, attachment surfaces, and splitting are chemically defined. A major improvement is the lack of a serum albumin component, as variations in either animal or human sourced albumin batches have previously plagued human ES and iPS cell culture with inconsistencies. Using this new medium (E8) and vitronectin-coated surfaces, we demonstrate improved derivation efficiencies of vector-free human iPS cells with an episomal approach. This simplified E8 medium should facilitate both the research use and clinical applications of human ES and iPS cells and their derivatives, and should be applicable to other reprogramming methods. PMID:21478862

  13. The Photodetachment of Ps ion and Low-Energy e(+) -H Collisions

    NASA Technical Reports Server (NTRS)

    Ward, S.J.

    2007-01-01

    Two calculations in the area of positron collisions are presented. The first is the calculation of the photodetachment cross section of the positronium negative ion (Ps-) using accurate variational wave functions for both the initial bound-state and the final P continuum state. The second is the calculation of partial wave cross sections for Ps(1s)-formation in ef -H(ls) collisions using the hyperspherical hidden crossing method. Since the S-wave Stiickelberg phase is close to pi, the very small S-wave Ps(1s) formation cross section can be understood in terms of destructive interference. Other examples in positron collisions are given where it is either known or expected that destructive interference is the cause of the small S-wave Ps(1s) formation cross section. In addition, examples are presented of processes in atomic physics where the Stiickelberg phase is a multiple of pi/2.

  14. Hyperspherical hidden crossing calculation of Ps formation in low-energy e+-Na collisions

    NASA Astrophysics Data System (ADS)

    Ward, S. J.; Shertzer, J.

    2011-05-01

    The hyperspherical hidden crossing method (HHCM) can provide important insight into scattering processes. Previously, we have used the HHCM to calculate the Ps(1s)-formation cross section in low-energy e+-H and e+-Li collisions. Here we apply the HHCM to low-energy e+-Na collisions. We use the Peach model potential and treat e+e-Na+ as an effective three-body system. We calculate the Ps(1s)-formation cross sections for 0 <= L <= 3 and compare our results with a hyperspherical close-coupling calculation. The HHCM provides an explanation for the small S-wave Ps(1s)-formation cross section. The S-wave Stückelberg phase is close to π for the three collision systems due to destructive interference between the two amplitudes that correspond to different paths leading to Ps(1s) formation.

  15. 2. P.S. Rittermann, Photographer February 1995 BUILDING 990, WEST SIDE. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. P.S. Rittermann, Photographer February 1995 BUILDING 990, WEST SIDE. - Presidio of San Francisco, Flammable Storage Building Submarine Mine Depot, Fort Point vicinity, Long Avenue, San Francisco, San Francisco County, CA

  16. PS-Analysis Of COSMO SAR Data Stacks Through A Fast And Simple Technique

    NASA Astrophysics Data System (ADS)

    Riva, Davide; D'Aria, Davide; Giudici, Davide; Guarnieri, Andrea Monti; Recchia, Andrea; Tagliani, Nicolas; Tebaldini, Stefano; Mancon, Simone

    2012-01-01

    This paper shows the results obtained with a Persistent Scatterers analysis over an X-band satellite interferometric dataset, acquired by three sensors of the COSMO SKYMED constellation over Milan, Italy. The accurate Persistent Scatterers analysis technique that leads to the estimation of the PS velocity, phase and displacement is briefly introduced. The PS analysis method performs the estimation by exploiting the differential atmospheric correction of the phases and then estimating the velocity through DFT.

  17. Topoisomerase-I PS506 as a Dual Function Cancer Biomarker

    PubMed Central

    Zhao, Ming; Gjerset, Ruth A.

    2015-01-01

    Novel biomarkers for cancer diagnosis and therapy selection are urgently needed to facilitate early detection and improve therapy outcomes. We have previously identified a novel phosphorylation site at serine 506 (PS506) on topoisomerase-I (topo-I) and have shown that it is widely expressed in cell lines derived from several cancers, including lung cancer, but is low in cell lines derived from non-cancerous tissues. Here we have investigated how PS506 expression in lung tissue specimens correlates with their malignant status. We find that PS506 expression is significantly elevated in malignant tumors of non-small cell lung cancer (NSCLC) compared to adjacent, non-cancerous lung tissue and benign lung tumors. PS506 expression was up to 6-fold higher in malignant specimens than in paired non-malignant tissue. Using the well-characterized NIH/NCI 60-cell line panel, we correlate the most elevated expression levels of PS506 in lung, ovarian, and colon cancer cells lines with increased sensitivity to camptothecin, a plant alkaloid that targets topo-I. This is consistent with our earlier studies in a smaller sampling of cell lines and with our finding that PS506 increases topo-I DNA binding. Two widely used chemotherapeutic drugs for ovarian and colon cancer, topotecan and irinotecan, respectively, are derived from camptothecin. Irinotecan has also displayed efficacy in clinical trials of NSCLC. Our results suggest that elevated PS506 expression may correlate with clinical chemosensitivity to these agents in ovarian, colon, and NSCLC. PS506 may therefore serve as a biomarker for diagnosis or therapy selection. PMID:26248194

  18. 7 CFR 1753.47 - Plans and specifications (P&S).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... from the approved LD (7 CFR part 1737) must be approved by RUS (See § 1753.3). (2) The standard RUS... 7 Agriculture 11 2011-01-01 2011-01-01 false Plans and specifications (P&S). 1753.47 Section 1753... Construction by Contract § 1753.47 Plans and specifications (P&S). (a) General. (1) Prior to the preparation...

  19. E-Cloud Drivent Single-Bunch Instabilities in PS2

    SciTech Connect

    Venturini, M.; Furman, M.; Penn, G.; Secondo, R.; Vay, J-L.; De Maria, R.; Papaphilippou, Y.; Rumolo, G.

    2010-05-23

    One of the proposals under consideration for future upgrades of the LHC injector complex entails the replacement of the PS with the PS2, a longer circumference and higher energy synchrotron, with electron cloud effects representing a potentially serious limitation to the achievement of the upgrade goals. We report on ongoing numerical studies aiming at estimating the e-cloud density threshold for the occurrence of single bunch instabilities.

  20. Necrotic Cells Actively Attract Phagocytes through the Collaborative Action of Two Distinct PS-Exposure Mechanisms

    PubMed Central

    Li, Zao; Venegas, Victor; Nagaoka, Yuji; Morino, Eri; Raghavan, Prashant; Audhya, Anjon; Nakanishi, Yoshinobu; Zhou, Zheng

    2015-01-01

    Necrosis, a kind of cell death closely associated with pathogenesis and genetic programs, is distinct from apoptosis in both morphology and mechanism. Like apoptotic cells, necrotic cells are swiftly removed from animal bodies to prevent harmful inflammatory and autoimmune responses. In the nematode Caenorhabditis elegans, gain-of-function mutations in certain ion channel subunits result in the excitotoxic necrosis of six touch neurons and their subsequent engulfment and degradation inside engulfing cells. How necrotic cells are recognized by engulfing cells is unclear. Phosphatidylserine (PS) is an important apoptotic-cell surface signal that attracts engulfing cells. Here we observed PS exposure on the surface of necrotic touch neurons. In addition, the phagocytic receptor CED-1 clusters around necrotic cells and promotes their engulfment. The extracellular domain of CED-1 associates with PS in vitro. We further identified a necrotic cell-specific function of CED-7, a member of the ATP-binding cassette (ABC) transporter family, in promoting PS exposure. In addition to CED-7, anoctamin homolog-1 (ANOH-1), the C. elegans homolog of the mammalian Ca2+-dependent phospholipid scramblase TMEM16F, plays an independent role in promoting PS exposure on necrotic cells. The combined activities from CED-7 and ANOH-1 ensure efficient exposure of PS on necrotic cells to attract their phagocytes. In addition, CED-8, the C. elegans homolog of mammalian Xk-related protein 8 also makes a contribution to necrotic cell-removal at the first larval stage. Our work indicates that cells killed by different mechanisms (necrosis or apoptosis) expose a common “eat me” signal to attract their phagocytic receptor(s); furthermore, unlike what was previously believed, necrotic cells actively present PS on their outer surfaces through at least two distinct molecular mechanisms rather than leaking out PS passively. PMID:26061275

  1. SALT spectroscopic classification of PS15bqc as a type-IIb SN before maximum light

    NASA Astrophysics Data System (ADS)

    Jha, S. W.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Smith, K. W.; Wright, D.; Smartt, S. J.; Huber, M.; Chambers, K. C.; Flewelling, H.; Willman, M.; Primak, N.; Schultz, A.; Gibson, B.; Magnier, E.; Waters, C.; Tonry, J.; Wainscoat, R. J.; Miszalski, B.

    2015-08-01

    We obtained SALT (+RSS) spectroscopy of PS15bqc on 2015 Aug 10.8 UT, covering the wavelength range 340-920 nm. Cross-correlation of the spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows PS15bqc is likely a type-IIb supernova a few days before maximum light, with good matches to spectra of SN 1993J at -3 or -2 days from maximum.

  2. 7 CFR 1753.47 - Plans and specifications (P&S).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... from the approved LD (7 CFR part 1737) must be approved by RUS (See § 1753.3). (2) The standard RUS... 7 Agriculture 11 2012-01-01 2012-01-01 false Plans and specifications (P&S). 1753.47 Section 1753... Construction by Contract § 1753.47 Plans and specifications (P&S). (a) General. (1) Prior to the preparation...

  3. 7 CFR 1753.47 - Plans and specifications (P&S).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... from the approved LD (7 CFR part 1737) must be approved by RUS (See § 1753.3). (2) The standard RUS... 7 Agriculture 11 2014-01-01 2014-01-01 false Plans and specifications (P&S). 1753.47 Section 1753... Construction by Contract § 1753.47 Plans and specifications (P&S). (a) General. (1) Prior to the preparation...

  4. 7 CFR 1753.47 - Plans and specifications (P&S).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... from the approved LD (7 CFR part 1737) must be approved by RUS (See § 1753.3). (2) The standard RUS... 7 Agriculture 11 2013-01-01 2013-01-01 false Plans and specifications (P&S). 1753.47 Section 1753... Construction by Contract § 1753.47 Plans and specifications (P&S). (a) General. (1) Prior to the preparation...

  5. APP/PS1 transgenic mice treated with aluminum: an update of Alzheimer's disease model.

    PubMed

    Zhang, Q L; Jia, L; Jiao, X; Guo, W L; Ji, J W; Yang, H L; Niu, Q

    2012-01-01

    There is still no animal model available that can mimic all the cognitive, behavioral, biochemical, and histopathological abnormalities observed in patients with Alzheimer's disease (AD). We undertook to consider the interaction between genetic factors, including amyloid precursor protein (APP) and presenilin-1 (PS1), and environmental factors, such as Aluminum (Al) in determining susceptibility outcomes when studying the pathogenesis of AD. In this article, we provide an AD model in APP/PS1 transgenic mice triggered by Al. The animal model was established via intracerebral ventricular microinjection of aluminum chloride once a day for 5 days in APP/PS1 transgenic mice. Twenty wild type (WT) mice and 20 APP/PS1 transgenic (TG) mice were separately divided into 2 groups (control and Al group), and a stainless steel injector with stopper was used for microinjection into the left-lateral cerebral ventricle of each mouse. The Morris water maze task was used to evaluate behavioral function of learning and memory ability on the 20th day after the last injection. This AD model's brain was analyzed by: (1) amyloid beta immunohistochemical staining; (2) Tunnel staining; (3) apoptotic rates; (4) caspase-3 gene expression. Here, decrease of cognitive ability and neural cells loss were shown in APP/PS1 transgenic mice exposed to Al, which were more extensive than those in APP/PS1 TG alone and WT mice exposed to Al alone. These findings indicate that there is a close relationship between over-expression of APP and PS1 genes and Al overload. It is also suggested that APP/PS1 TG mice exposed to Al have potential value for improving AD models. PMID:22507317

  6. Perceptions of Community Health Workers (CHWs/PS) in the U.S.-Mexico Border HEART CVD Study

    PubMed Central

    Balcazar, Hector G.; Wise, Sherrie; Redelfs, Alisha; Rosenthal, E. Lee; de Heer, Hendrik D.; Burgos, Ximena; Duarte-Gardea, Maria

    2014-01-01

    Although prior research has shown that Community Health Workers/Promotores de Salud (CHW/PS) can facilitate access to care, little is known about how CHW/PS are perceived in their community. The current study reports the findings of a randomized telephone survey conducted in a high-risk urban community environment along the U.S.-Mexico border. In preparation for a community-based CHW/PS intervention called the HEART ecological study, the survey aimed to assess perceptions of CHW/PS, availability and utilization of community resources (recreational and nutrition related) and health behaviors and intentions. A total of 7,155 calls were placed to complete 444 surveys in three zip codes in El Paso, Texas. Results showed that participants felt that healthful community resources were available, but utilization was low and variable: 35% reported going to a park, 20% reported having taken a health class, few reported using a gym (12%), recreation center (8%), or YMCA/YWCA (0.9%). Awareness and utilization of CHW/PS services were low: 20% of respondents had heard of CHW/PS, with 8% reporting previous exposure to CHW/PS services. Upon review of a definition of CHW/PS, respondents expressed positive views of CHW/PS and their value in the healthcare system. Respondents who had previous contact with a CHW/PS reported a significantly more positive perception of the usefulness of CHW/PS (p = 0.006), were more likely to see CHW/PS as an important link between providers and patients (p = 0.008), and were more likely to ask a CHW/PS for help (p = 0.009). Participants who utilized CHW/PS services also had significantly healthier intentions to reduce fast food intake. Future research is needed to evaluate if CHW/PS can facilitate utilization of available community resources such as recreational facilities among Hispanic border residents at risk for CVD. PMID:24518646

  7. Perceptions of Community Health Workers (CHWs/PS) in the U.S.-Mexico border HEART CVD study.

    PubMed

    Balcazar, Hector G; Wise, Sherrie; Redelfs, Alisha; Rosenthal, E Lee; de Heer, Hendrik D; Burgos, Ximena; Duarte-Gardea, Maria

    2014-02-01

    Although prior research has shown that Community Health Workers/Promotores de Salud (CHW/PS) can facilitate access to care, little is known about how CHW/PS are perceived in their community. The current study reports the findings of a randomized telephone survey conducted in a high-risk urban community environment along the U.S.-Mexico border. In preparation for a community-based CHW/PS intervention called the HEART ecological study, the survey aimed to assess perceptions of CHW/PS, availability and utilization of community resources (recreational and nutrition related) and health behaviors and intentions. A total of 7,155 calls were placed to complete 444 surveys in three zip codes in El Paso, Texas. Results showed that participants felt that healthful community resources were available, but utilization was low and variable: 35% reported going to a park, 20% reported having taken a health class, few reported using a gym (12%), recreation center (8%), or YMCA/YWCA (0.9%). Awareness and utilization of CHW/PS services were low: 20% of respondents had heard of CHW/PS, with 8% reporting previous exposure to CHW/PS services. Upon review of a definition of CHW/PS, respondents expressed positive views of CHW/PS and their value in the healthcare system. Respondents who had previous contact with a CHW/PS reported a significantly more positive perception of the usefulness of CHW/PS (p = 0.006), were more likely to see CHW/PS as an important link between providers and patients (p = 0.008), and were more likely to ask a CHW/PS for help (p = 0.009). Participants who utilized CHW/PS services also had significantly healthier intentions to reduce fast food intake. Future research is needed to evaluate if CHW/PS can facilitate utilization of available community resources such as recreational facilities among Hispanic border residents at risk for CVD. PMID:24518646

  8. PS-InSAR processing methodologies in the detection of field surface deformation—Study of the Granada basin (Central Betic Cordilleras, southern Spain)

    NASA Astrophysics Data System (ADS)

    Sousa, Joaquim J.; Ruiz, Antonio M.; Hanssen, Ramon F.; Bastos, Luisa; Gil, Antonio J.; Galindo-Zaldívar, Jesús; Sanz de Galdeano, Carlos

    2010-04-01

    Differential SAR interferometry (DInSAR) is a very effective technique for measuring crustal deformation. However, almost all interferograms include large areas where the signals decorrelate and no measurements are possible. Persistent scatterer interferometry (PS-InSAR) overcomes the decorrelation problem by identifying resolution elements whose echo is dominated by a single scatterer in a series of interferograms. Two time series of 29 ERS-1/2 and 22 ENVISAT ASAR acquisitions of the Granada basin, located in the central sector of the Betic Cordillera (southern Spain), covering the period from 1992 to 2005, were analyzed. Rough topography of the study area associated to its moderate activity geodynamic setting, including faults and folds in an uplifting relief by the oblique Eurasian-African plate convergence, poses a challenge for the application of interferometric techniques. The expected tectonic deformation rates are in the order of ˜1 mm/yr, which are at the feasibility limit of current InSAR techniques. In order to evaluate whether, under these conditions, InSAR techniques can still be used to monitor deformations we have applied and compared two PS-InSAR approaches: DePSI, the PS-InSAR package developed at Delft University of Technology (TU Delft) and StaMPS (Stanford Method for Persistent Scatterers) developed at Stanford University. Ground motion processes have been identified for the first time in the study area, the most significant process being a subsidence bowl located at the village of Otura. The idea behind this comparative study is to analyze which of the two PS-InSAR approaches considered might be more appropriate for the study of specific areas/environments and to attempt to evaluate the potentialities and benefits that could be derived for the integration of those methodologies.

  9. PS-OCT of occlusal and interproximal caries lesions viewed from occlusal surfaces

    NASA Astrophysics Data System (ADS)

    Ngaotheppitak, Patara; Darling, Cynthia L.; Fried, Daniel; Bush, Jeff; Bell, Steve

    2006-02-01

    Previous studies have demonstrated that Polarization Sensitive Optical Coherence Tomography (PS-OCT) can be used to image early dental caries. The primary objective of this study was to compare the measured reflectivity of natural occlusal caries lesions with the relative mineral loss measured using digital microradiography. There was excellent agreement between the increase in the integrated reflectivity in the perpendicular polarization axis of the PS-OCT system and the increase in the integrated mineral loss or lesion severity for occlusal lesions. Therefore, PS-OCT is ideally suited to image natural caries lesions in the important occlusal surfaces for the assessment of the lesion severity and activity. A secondary objective was to compare the performance of a new autocorrelator-based PS-OCT system employing a novel polarization-switching probe with our polarization-maintaining fiber based PS-OCT system, both operating at 1310-nm. The new PS-OCT system produced clean images with no artifacts and achieved high penetration depth. Yet a third objective was to determine if interproximal lesions can be imaged from the occlusal surface (from above) since interproximal lesions may only be accessible in vivo from buccal or lingual surfaces or from the occlusal surface. Simulated and natural interproximal caries lesions were imaged from the occlusal surfaces as long as there was no intervening dentin.

  10. Community Perspectives Associated With the African PsA-TT (MenAfriVac) Vaccine Trials

    PubMed Central

    Idoko, Olubukola T.; Diallo, Aldiouma; Sow, Samba O.; Hodgson, Abraham; Akinsola, Adebayo; Diarra, Bou; Haidara, Fadima Cheick; Ansah, Patrick Odum; Kampmann, Beate; Bouma, Enricke; Preziosi, Marie-Pierre; Enwere, Godwin C.

    2015-01-01

    Background. The Meningitis Vaccine Project (MVP) was established to address epidemic meningitis as a public health problem in sub-Saharan Africa and, to that end, worked to develop a group A meningococcal conjugate vaccine, PsA-TT. Methods. Experiences in 4 clinical trial sites are described. Culturally sensitive collaborative strategies were adopted to manage acceptable communication methods, peculiarities with the consent process, participant medical issues, community care, and death. Results. The clinical trials were completed successfully through community acceptance and active community collaboration. The trials also strengthened the capacities in the participating communities, and actively worked to resolve community problems. Conclusions. The understanding and integration of sociocultural realities of communities were major assets in the conduct and acceptance of these trials. MVP succeeded in these sites and provided a sound example for future clinical studies in Africa. Clinical Trials Registration. ISRTCN78147026 (PsA-TT 002); ISRCTN87739946 (PsA-TT 003); ISRCTN82484612 (PsA-TT 004); PACTR ATMR2010030001913177 (PsA-TT 006); and PACTR201110000328305 (PsA-TT 007). PMID:26553669

  11. Construction of a chromosome map for the phage group II Staphylococcus aureus Ps55.

    PubMed Central

    Bannantine, J P; Pattee, P A

    1996-01-01

    The genome size and a partial physical and genetic map have been defined for the phage group II Staphylococcus aureus Ps55. The genome size was estimated to be 2,771 kb by pulsed-field gel electrophoresis (PFGE) using the restriction enzymes SmaI, CspI, and SgrAI. The Ps55 chromosome map was constructed by transduction of auxotrophic and cryptic transposon insertions, with known genetic and physical locations in S. aureus NCTC 8325, into the Ps55 background. PFGE and DNA hybridization analysis were used to detect the location of the transposon in Ps55. Ps55 restriction fragments were then ordered on the basis of genetic conservation between the two strains. Cloned DNA probes containing the lactose operon (lac) and genes encoding staphylococcal protein A (spa), gamma hemolysin (hlg), and coagulase (coa) were also located on the map by PFGE and hybridization analysis. This methodology enabled a direct comparison of chromosomal organization between NCTC 8325 and Ps55 strains. The chromosome size, gene order, and some of the restriction sites are conserved between the two phage group strains. PMID:8955305

  12. Relation of P-S4 interval to left ventricular end-diastolic pressure.

    PubMed Central

    Schapira, J N; Fowles, R E; Bowden, R E; Alderman, E L; Popp, R L

    1982-01-01

    Reports have suggested that the interval between P wave onset and the fourth heart sound (P-S4 interval) reflects changes in left ventricular myocardial stiffness. We made simultaneous measurements of the P-S4 or atrial electrogram to S4 (A-S4) interval and left ventricular pressure in 19 patients with coronary artery disease who were studied before and after atrial pacing. Thirteen patients developed angina accompanied by significant rises in their end-diastolic pressure and a consistent decrease in P-S4 or A-S4 interval; whereas the six patients who had atrial pacing without the development of angina had no change in end-diastolic pressure, P-S4, or A-S4 interval. The resting data showed in inverse correlation between left ventricular end-diastolic pressure and the P-S4 interval. In addition, the P-S4 interval let us discriminate between patients with normal and abnormal end-diastolic pressure (greater than 15 mmHg). Images PMID:7059403

  13. Cloning and expression of the sucrose transporter gene PsSUT1 from tree peony leaf.

    PubMed

    Li, Y H; Guo, T; Cui, Y; Li, Y; He, D

    2015-01-01

    This study reports the cloning of a sucrose transporter gene, PsSUT1, from the leaf of tree peony (Paeonia suffruticosa Lind. cv 'Huhong'). Expression patterns were examined in different organs and at different developmental stages. The full-length cDNA of PsSUT1 consisted of a 2001-bp sequence containing a 1557-bp open reading frame, encoding 519 amino acids with a conserved domain typical of the glycoside-pentoside-hexuronide superfamily. The amino acid sequence of PsSUT1 in tree peony shared high homology with that of other plants. At different developmental stages, PsSUT1 was expressed in roots, stems, leaves, and petals. Its expression level in stems was 10.9-fold higher than in petals at the flowering stage. Expression of PsSUT1 at the flowering stage was highest during flower development. The significant differences in PsSUT1 expression observed among developmental stages and organs were closely related to changes in sucrose content during flower opening. These results form the basis for further research on the molecular mechanisms of carbohydrate metabolism and transport during flower development in tree peony. PMID:26505390

  14. Efficient genomic correction methods in human iPS cells using CRISPR-Cas9 system.

    PubMed

    Li, Hongmei Lisa; Gee, Peter; Ishida, Kentaro; Hotta, Akitsu

    2016-05-15

    Precise gene correction using the CRISPR-Cas9 system in human iPS cells holds great promise for various applications, such as the study of gene functions, disease modeling, and gene therapy. In this review article, we summarize methods for effective editing of genomic sequences of iPS cells based on our experiences correcting dystrophin gene mutations with the CRISPR-Cas9 system. Designing specific sgRNAs as well as having efficient transfection methods and proper detection assays to assess genomic cleavage activities are critical for successful genome editing in iPS cells. In addition, because iPS cells are fragile by nature when dissociated into single cells, a step-by-step confirmation during the cell recovery process is recommended to obtain an adequate number of genome-edited iPS cell clones. We hope that the techniques described here will be useful for researchers from diverse backgrounds who would like to perform genome editing in iPS cells. PMID:26525194

  15. Preparation of pancreatic β-cells from human iPS cells with small molecules.

    PubMed

    Hosoya, Masaki

    2012-01-01

    Human induced pluripotent stem (iPS) cells obtained from patients are expected to be a useful source for cell transplantation therapy, because many patients (including those with type 1 diabetes and severe type 2 diabetes) are on waiting lists for transplantation for a long time due to the shortage of donors. At present, many concerns related to clinical application of human iPS cells have been raised, but rapid development of methods for the establishment, culture, and standardization of iPS cells will lead autologous cell therapy to be realistic sooner or later. However, establishment of a method for preparing some of desired cell types is still challenging. Regarding pancreatic β-cells, there have been many reports about differentiation of these cells from human embryonic stem (ES)/iPS cells, but a protocol for clinical application has still not been established. Since there is clear proof that cell transplantation therapy is effective for diabetes based on the results of clinical islet transplantation, pancreatic β-cells prepared from human iPS cells are considered likely to be effective for reducing the burden on patients. In this article, the current status of procedures for preparing pancreatic β-cells from human ES/iPS cells, including effective use of small molecules, is summarized, and some of the problems that still need to be overcome are discussed. PMID:22722666

  16. New molecular-scale information on polystyrene dynamics in PS and PS-BaTiO3 composites from FTIR spectroscopy.

    PubMed

    Olmos, D; Martín, E V; González-Benito, J

    2014-11-28

    A new idea to understand the macromolecular motion occurring along the thermal relaxations of polystyrene (PS) and PS-barium titanate composites is proposed. Detailed analysis of PS infrared bands provides a better knowledge of the factors affecting polymer dynamics. Average spectral positions and integrated absorbance of bands in the region of C-H out-of-plane vibrations showed a continuous decrease with temperature, whereas those in the region of aliphatic and aromatic C-H stretching vibrations showed the sharpest changes with temperature. Relaxation temperatures were determined from the changes observed in the band wavenumber or area with temperature. These results were attributed to changes in the distribution of the phenyl π-electron cloud, causing important dipole moment variations in the different vibration modes when the thermal transitions are taking place. Finally, although the presence of BaTiO3 particles does not seem to exert any specific effect on the PS dynamics in the glassy state, the Curie transition of these particles might induce a kind of confinement effect observable by FTIR. PMID:25301098

  17. Paper sludge (PS) to bioethanol: Evaluation of virgin and recycle mill sludge for low enzyme, high-solids fermentation.

    PubMed

    Boshoff, Sonja; Gottumukkala, Lalitha Devi; van Rensburg, Eugéne; Görgens, Johann

    2016-03-01

    Paper sludge (PS) from the paper and pulp industry consists primarily of cellulose and ash and has significant potential for ethanol production. Thirty-seven PS samples from 11 South African paper and pulp mills exhibited large variation in chemical composition and resulting ethanol production. Simultaneous saccharification and fermentation (SSF) of PS in fed-batch culture was investigated at high solid loadings and low enzyme dosages. Water holding capacity and viscosity of the PS influenced ethanol production at elevated solid loadings of PS. High viscosity of PS from virgin pulp mills restricted the solid loading to 18% (w/w) at an enzyme dosage of 20 FPU/gram dry PS (gdPS), whereas an optimal solid loading of 27% (w/w) was achieved with corrugated recycle mill PS at 11 FPU/gdPS. Ethanol concentration and yield of virgin pulp and corrugated recycle PS were 34.2g/L at 66.9% and 45.5 g/L at 78.2%, respectively. PMID:26722809

  18. Structure and inhibition studies of a type II beta-carbonic anhydrase psCA3 from Pseudomonas aeruginosa.

    PubMed

    Pinard, Melissa A; Lotlikar, Shalaka R; Boone, Christopher D; Vullo, Daniela; Supuran, Claudiu T; Patrauchan, Marianna A; McKenna, Robert

    2015-08-01

    Carbonic anhydrases (CAs) are metallo-enzymes that catalyze the reversible hydration of carbon dioxide into bicarbonate and a proton. The β-class CAs (β-CAs) are expressed in prokaryotes, fungi, plants, and more recently have been isolated in some animals. The β-CA class is divided into two subclasses, termed type I and II, defined by pH catalytic activity profile and active site structural configuration. Type I β-CAs display catalytic activity over a broad pH range (6.5-9.0) with the active site zinc tetrahedrally coordinated by three amino acids and a hydroxide/water. In contrast, type II β-CAs are catalytically active only at a pH 8 and higher where they adopt a functional active site configuration like that of type I. However, below pH 8 they are conformationally self-inactivated by the addition of a fourth amino acid coordinating the zinc and thereby displacing the zinc bound solvent. We have determined the structure of psCA3, a type II β-CA, isolated from Pseudomonas aeruginosa (P. aeruginosa) PAO1 at pH 8.3, in its open active state to a resolution of 1.9 Å. The active site zinc is coordinated by Cys42, His98, Cys101 and a water/hydroxide molecule. P. aeruginosa is a multi-drug resistant bacterium and displays intrinsic resistance to most of the currently used antibiotics; therefore, there is a need for new antibacterial targets. Kinetic data confirm that psCA3 belongs to the type II subclass and that sulfamide, sulfamic acid, phenylboronic acid and phenylarsonic acid are micromolar inhibitors. In vivo studies identified that among six tested inhibitors representing sulfonamides, inorganic anions, and small molecules, acetazolamide has the most significant dose-dependent inhibitory effect on P. aeruginosa growth. PMID:26068018

  19. Validity and Reliability of the Dutch Adaptation of the Psoriatic Arthritis Quality of Life (PsAQoL) Questionnaire

    PubMed Central

    McKenna, Stephen P.; Houtman, Pieternella M.; Brouwer, Elisabeth; Spoorenberg, Anneke

    2013-01-01

    Objective The Psoriatic Arthritis Quality of Life (PsAQoL) questionnaire is a disease- specific instrument developed to measure quality of life (QoL) in patients with psoriatic arthritis (PsA). The aim of this study was to translate the measure into Dutch and to determine its psychometric properties. Method Translation of the original English PsAQoL into Dutch was performed by bilingual and lay panel. Ten field-test interviews with PsA patients were performed to assess face and content validity. In total, 211 PsA patients were included in a test-retest postal survey to investigate the reliability and construct validity of the Dutch adaptation of the PsAQoL. The PsAQoL, Health Assessment Questionnaire (HAQ) and Skindex-17 were administered on two different occasions approximately two weeks apart. Results The Dutch version of the PsAQoL was found to be relevant, understandable and easy to complete in only a few minutes. It correlated as expected with the HAQ (Spearman’s ρ = 0.72) and the 2 subscales of the Skindex-17 (ρ = 0.40 for the psychosocial and ρ = 0.46 for the symptom scale). Furthermore, the measure had good internal consistency (Cronbach’s α = 0.92) and test-retest reliability (ρ = 0.89). The PsAQoL was able to define groups of patients based on self-reported general health status, self-reported severity of PsA and flare of arthritis. Duration of PsA did not influence PsAQoL scores. Conclusions The Dutch version of the PsAQoL is a valid and reliable questionnaire suitable for use in clinical or research settings to asses PsA-specific QoL. PMID:23418474

  20. Ultra-high resolution polarization-sensitive optical coherence microscopy for brain imaging at 6 um, 3.4 um and 1.3 um resolution (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Akkin, Taner; Magnain, Caroline V.; Yaseen, Mohammad A.; Cramer, Avilash; Wang, Ruopeng; Sakadžic, Sava; Boas, David A.

    2016-03-01

    Neuroanatomical pathways form the basis for functional activity of brain circuits. In the past, we developed a polarization-sensitive optical coherence tomography with serial scanning to achieve large-scale brain imaging. The system was able to visualize 3D fiber tracts of ~20 um in diameter. To investigate the neuroanatomical pathways at finer scales, we have now built a polarization-maintaining fiber based ultra-high resolution polarization-sensitive optical coherence microscope (PS-OCM) at 1300 nm. The PS-OCM has an axial resolution of 3.5 um in tissue. The detection setup consists of two spectrometers, acquiring spectral interference on orthogonal polarization channels. With a single measurement, the setup generates four contrasts: reflectivity, cross-polarization, retardance and optic axis orientation. To investigate the capability of PS-OCM at different resolutions, we used three microscope objectives that yield lateral resolutions of 6.0 um, 3.4 um and 1.3 um. Blocks of formalin fixed mouse brain and human brain were scanned. The cross-polarization and retardance images clearly depict the neuronal fiber structures, which are comparable with that generated by the maximum projection of volumetric reflectivity data. The optic axis orientation quantifies the in-plane fiber orientation. With the lateral resolution of 1.3 um, the retardance contrast is weak in white matter due to the shallow depth of focus. Overall, the ultra-high resolution PS-OCM provides a new tool to reveal neuroanatomical maps in the brain at cellular resolution.

  1. Modeling Alzheimer's disease with human induced pluripotent stem (iPS) cells.

    PubMed

    Mungenast, Alison E; Siegert, Sandra; Tsai, Li-Huei

    2016-06-01

    In the last decade, induced pluripotent stem (iPS) cells have revolutionized the utility of human in vitro models of neurological disease. The iPS-derived and differentiated cells allow researchers to study the impact of a distinct cell type in health and disease as well as performing therapeutic drug screens on a human genetic background. In particular, clinical trials for Alzheimer's disease (AD) have been failing. Two of the potential reasons are first, the species gap involved in proceeding from initial discoveries in rodent models to human studies, and second, an unsatisfying patient stratification, meaning subgrouping patients based on the disease severity due to the lack of phenotypic and genetic markers. iPS cells overcome this obstacles and will improve our understanding of disease subtypes in AD. They allow researchers conducting in depth characterization of neural cells from both familial and sporadic AD patients as well as preclinical screens on human cells. In this review, we briefly outline the status quo of iPS cell research in neurological diseases along with the general advantages and pitfalls of these models. We summarize how genome-editing techniques such as CRISPR/Cas9 will allow researchers to reduce the problem of genomic variability inherent to human studies, followed by recent iPS cell studies relevant to AD. We then focus on current techniques for the differentiation of iPS cells into neural cell types that are relevant to AD research. Finally, we discuss how the generation of three-dimensional cell culture systems will be important for understanding AD phenotypes in a complex cellular milieu, and how both two- and three-dimensional iPS cell models can provide platforms for drug discovery and translational studies into the treatment of AD. PMID:26657644

  2. Active quenching and gating circuit of the photon counting detector for laser time transfer with improved timing resolution and stability

    NASA Astrophysics Data System (ADS)

    Prochazka, Ivan; Blazej, Josef; Kodet, Jan; Michalek, Vojtech

    2015-05-01

    We are presenting the results of research and development of a new active quenching and gating electronics for Single Photon Avalanche Detector (SPAD). The goal of the work was to develop a new SPAD detector package for Laser Time Transfer ground to space with improved timing resolution and stability. The first version of a SPAD detector is operational on board of GNSS navigation satellites. They are based on 25 μm diameter K14 series SPAD chips. They do provide timing resolution of typically 125 ps and stability of the order of 10 ps. The new control electronics provides timing resolution of 25 ps and timing stability and drifts of the order of one picosecond. The device is constructed on a basis of electronics components for which the space qualified equivalents are commercially available. The device construction, tests and results will be presented in detail.

  3. Analysis of single-photon time resolution of FBK silicon photomultipliers

    NASA Astrophysics Data System (ADS)

    Acerbi, Fabio; Ferri, Alessandro; Gola, Alberto; Zorzi, Nicola; Piemonte, Claudio

    2015-07-01

    We characterized and analyzed an important feature of silicon photomultipliers: the single-photon time resolution (SPTR). We characterized the SPTR of new RGB (Red-Green-Blue) type Silicon Photomultipliers and SPADs produced at FBK (Trento, Italy), studying its main limiting factors. We compared time resolution of 1×1 mm2 and 3×3 mm2 SiPMs and a single SiPM cell (i.e. a SPAD with integrated passive-quenching), employing a mode-locked pulsed laser with 2-ps wide pulses. We estimated the contribution of front-end electronic-noise, of cell-to-cell uniformity, and intrinsic cell time-resolution. At a single-cell level, we compared the results obtained with different layouts. With a circular cell with a top metallization covering part of the edge and enhancing the signal extraction, we reached ~20 ps FWHM of time resolution.

  4. Laser induced breakdown spectroscopy of pure aluminum with high temporal resolution.

    PubMed

    Li, Yu-Tai; Liu, Tze-An; Chen, Chen-Wei; Lee, Yu-Hsien; Yabushita, Atsushi

    2013-09-01

    We report on a Laser Induced Breakdown Spectroscopy (LIBS) system with a very high temporal resolution, using femtosecond and picosecond pulse laser excitation of pure aluminum (Al). By using a 140 fs Ti:Sapphire laser in an ultrafast optical Kerr gate (OKG), we demonstrate LIBS sampling with a sub-ps time resolution (0.8 ± 0.08 ps) in a 14 ns window. The width of the gating window in this system was as narrow as 0.8 ps, owing to the inclusion of a carbon disulfide (CS(2)) cell, which has a fast response and a large nonlinear coefficient. Furthermore, when using a 100 ps pulsed Nd:YAG laser and a fast photomultiplier tube (PMT) we demonstrate a LIBS system with a nanosecond time resolution (2.20 ± 0.08 ns) in a microsecond window. With this sort of temporal resolution, a non-continuous decay in the Al signal could be observed. After 50 ns decay of the first peak, the second peak at 230 ns is started to perform. Experimental results with such short temporal windows in LIBS, in both nanosecond and microsecond ranges, are important for fast temporal evolution measurements and observations of early continuum emission in materials. PMID:24104032

  5. Cavity-enhanced absorption spectroscopy with a ps-pulsed UV laser for sensitive, high-speed measurements in a shock tube.

    PubMed

    Wang, Shengkai; Sun, Kai; Davidson, David F; Jeffries, Jay B; Hanson, Ronald K

    2016-01-11

    We report the first application of cavity-enhanced absorption spectroscopy (CEAS) with a ps-pulsed UV laser for sensitive and rapid gaseous species time-history measurements in a transient environment (in this study, a shock tube). The broadband nature of the ps pulses enabled instantaneous coupling of the laser beam into roughly a thousand cavity modes, which grants excellent immunity to laser-cavity coupling noise in environments with heavy vibrations, even with an on-axis alignment. In this proof-of-concept experiment, we demonstrated an absorption gain of 49, which improved the minimum detectable absorbance by ~20 compared to the conventional single-pass strategy at similar experimental conditions. For absorption measurements behind reflected shock waves, an effective time-resolution of ~2 μs was achieved, which enabled time-resolved observations of transient phenomena, such as the vibrational relaxation of O(2) demonstrated here. The substantial improvement in detection sensitivity, together with microsecond measurement resolution implies excellent potential for studies of transient physical and chemical processes in nonequilibrium situations, particularly via measurements of weak absorptions of trace species in dilute reactive systems. PMID:26832262

  6. Biodegradation of waste greases and biochemical properties of a novel lipase from Pseudomonas synxantha PS1.

    PubMed

    Cai, Xianghai; Chen, Siqi; Yang, Hong; Wang, Wei; Lin, Lin; Shen, Yaling; Wei, Wei; Wei, Dong-Zhi

    2016-07-01

    A lipase-producing bacterial strain was isolated from oil-well-produced water in Shengli oilfield (Shandong province, China) and was identified as Pseudomonas synxantha by 16S rDNA sequence analysis (named Pseudomonas synxantha PS1). Strain PS1 showed a maximum lipase activity of 10.8 U/mL after culturing for 48 h at 30 °C, with lactose (4 g/L) as carbon source, tryptone (8 g/L) as nitrogen source, olive oil (0.5%, v/v) as inductor, and the initial pH 8.0. Meanwhile, the lipase gene from P. synxantha PS1 was cloned and expressed in Escherichia coli BL21 with the vector pET28a. The novel gene (lipPS1) has an open reading frame of 1425 bp and encodes a 474 aa lipase (LipPS1) sharing the most identity (87%) with the lipase in Pseudomonas fluorescens. LipPS1 preferably acted on substrates with a long chain (C10-C18) of fatty acids. The optimum pH and temperature of the recombinant enzyme were 8.0 and 40 °C, respectively, towards the optimum substrate p-nitrophenyl palmitate. The LipPS1 showed remarkable stability under alkaline conditions and was stable at pH 7.0-10.0 (retaining more than 60% activity). From the organic solvents tests, the lipase was activated by 15% (v/v) methanol (112%), 15% ethanol (127%), and 15% n-butyl alcohol (116%). LipPS1 presented strong biodegradability of waste grease; 93% of waste grease was hydrolyzed into fatty acid after 12 h at 30 °C. This is the first report of the lipase activity and lipase gene obtained from P. synxantha (including wild strain and recombinant strain) and of the recombinant LipPS1 with the detailed enzymatic properties. Also a preliminary study of the biodegradability of waste greases shows the potential value in industry applications. PMID:27321682

  7. Test and characterisation of SiPMs for the MEGII high resolution Timing Counter

    NASA Astrophysics Data System (ADS)

    Simonetta, M.; Biasotti, M.; Boca, G.; Cattaneo, P. W.; De Gerone, M.; Gatti, F.; Nardò, R.; Nishimura, M.; Ootani, W.; Pizzigoni, G.; Prata, M. C.; Rossella, M.; Shibata, N.; Uchiyama, Y.; Yoshida, K.

    2016-07-01

    The MEGII Timing Counter will measure the positron time of arrival with a resolution of ~ 30 ps relying on two arrays of scintillator pixels read out by 6144 Silicon Photomultipliers (SiPMs) from AdvanSiD. They are characterised, measuring their breakdown voltage, to assure that the gains of the SiPMs of each pixel are as uniform as possible, to maximise the pixel resolution. Gain measurements have also been performed.

  8. The Effect of Composition on the Surface Finish of PS400: A New High Temperature Solid Lubricant Coating

    NASA Technical Reports Server (NTRS)

    DellaCorte, Christopher; Stanford, malcolm K.; Thomas, Fransua; Edmonds, Brian J.

    2010-01-01

    A new composite, multi-constituent, solid lubricant coating, NASA PS400, developed for high temperature tribological applications, exhibits a smoother surface finish after grinding and polishing than its predecessors PS200 and PS300. In this paper, the baseline composition of PS400 is modified to investigate each individual constituent s role on the achievable surface finish through a series of coating deposition, grinding, and polishing experiments. Furthermore, to explore the limits of compositional tailoring for improved tribological performance, several PS400 coatings were doped with additional solid lubricants (graphite, MoS2 and BN) and tribologically tested. The test results clearly showed that, compared to PS300 coatings, PS400 achieves a smoother surface finish via a reduced lubricant content. Coatings prepared with higher than the baseline level (10 wt%) of lubricants exhibited higher final surface roughness than the earlier generation PS300 coatings. Reducing or eliminating the one or both lubricants (fluorides or silver) did not further improve the surface finish suggesting that the current composition of PS400 is near optimal with respect to surface finish. Lastly, attempts to improve the poor initial room temperature tribological behavior of PS400 via the addition of traditional solid lubricants were unsuccessful. Based upon this work and earlier results it is expected that future research will concentrate on developing methods to produce a lubricious glaze on the rubbing surface during break in to ensure that low friction and wear are rapidly achieved.

  9. Miniaturized iPS-Cell-Derived Cardiac Muscles for Physiologically Relevant Drug Response Analyses

    PubMed Central

    Huebsch, Nathaniel; Loskill, Peter; Deveshwar, Nikhil; Spencer, C. Ian; Judge, Luke M.; Mandegar, Mohammad A.; B. Fox, Cade; Mohamed, Tamer M.A.; Ma, Zhen; Mathur, Anurag; Sheehan, Alice M.; Truong, Annie; Saxton, Mike; Yoo, Jennie; Srivastava, Deepak; Desai, Tejal A.; So, Po-Lin; Healy, Kevin E.; Conklin, Bruce R.

    2016-01-01

    Tissue engineering approaches have the potential to increase the physiologic relevance of human iPS-derived cells, such as cardiomyocytes (iPS-CM). However, forming Engineered Heart Muscle (EHM) typically requires >1 million cells per tissue. Existing miniaturization strategies involve complex approaches not amenable to mass production, limiting the ability to use EHM for iPS-based disease modeling and drug screening. Micro-scale cardiospheres are easily produced, but do not facilitate assembly of elongated muscle or direct force measurements. Here we describe an approach that combines features of EHM and cardiospheres: Micro-Heart Muscle (μHM) arrays, in which elongated muscle fibers are formed in an easily fabricated template, with as few as 2,000 iPS-CM per individual tissue. Within μHM, iPS-CM exhibit uniaxial contractility and alignment, robust sarcomere assembly, and reduced variability and hypersensitivity in drug responsiveness, compared to monolayers with the same cellular composition. μHM mounted onto standard force measurement apparatus exhibited a robust Frank-Starling response to external stretch, and a dose-dependent inotropic response to the β-adrenergic agonist isoproterenol. Based on the ease of fabrication, the potential for mass production and the small number of cells required to form μHM, this system provides a potentially powerful tool to study cardiomyocyte maturation, disease and cardiotoxicology in vitro. PMID:27095412

  10. Contribution of Defective PS Recognition and Efferocytosis to Chronic Inflammation and Autoimmunity

    PubMed Central

    Kimani, Stanley Gititu; Geng, Ke; Kasikara, Canan; Kumar, Sushil; Sriram, Ganapathy; Wu, Yi; Birge, Raymond B.

    2014-01-01

    The rapid and efficient clearance of apoptotic cells results in the elimination of auto-antigens and provides a strong anti-inflammatory and immunosuppressive signal to prevent autoimmunity. While professional and non-professional phagocytes utilize a wide array of surface receptors to recognize apoptotic cells, the recognition of phosphatidylserine (PS) on apoptotic cells by PS receptors on phagocytes is the emblematic signal for efferocytosis in metazoans. PS-dependent efferocytosis is associated with the production of anti-inflammatory factors such as IL-10 and TGF-β that function, in part, to maintain tolerance to auto-antigens. In contrast, when apoptotic cells fail to be recognized and processed for degradation, auto-antigens persist, such as self-nucleic acids, which can trigger immune activation leading to autoantibody production and autoimmunity. Despite the fact that genetic mouse models clearly demonstrate that loss of PS receptors can lead to age-dependent auto-immune diseases reminiscent of systemic lupus erythematosus (SLE), the link between PS and defective clearance in chronic inflammation and human autoimmunity is not well delineated. In this perspective, we review emerging questions developing in the field that may be of relevance to SLE and human autoimmunity. PMID:25426118

  11. Genesis and Variability of [Ps1] Prion Factors in Saccharomyces Cerevisiae

    PubMed Central

    Derkatch, I. L.; Chernoff, Y. O.; Kushnirov, V. V.; Inge-Vechtomov, S. G.; Liebman, S. W.

    1996-01-01

    We have previously shown that multicopy plasmids containing the complete SUP35 gene are able to induce the appearance of the non-Mendelian factor [PS1]. This result was later interpreted by others as a crucial piece of evidence for a model postulating that [PS1] is a self-modified, prion-like conformational derivative of the Sup35 protein. Here we support this interpretation by proving that it is the overproduction of Sup35 protein, and not the excess of SUP35 DNA or mRNA that causes the appearance of [PS1]. We also show that the ``prion-inducing domain'' of Sup35p is in the N-terminal region, which, like the ``prion-inducing domain'' of another yeast prion, Ure2p, was previously shown to be distinct from the functional domain of the protein. This suggests that such a chimeric organization may be a common pattern of some prion elements. Finally, we find that [PS1] factors of different efficiencies and different mitotic stabilities are induced in the same yeast strain by overproduction of the identical Sup35 protein. We suggest that the different [PS1]-containing derivatives are analogous to the mysterious mammalian prion strains and result from different conformational variants of Sup35p. PMID:8978027

  12. The development of the Asian Forum for Polar Sciences (AFoPS)

    NASA Astrophysics Data System (ADS)

    Kim, Yeadong; Jeong, Jihoon

    2015-12-01

    The Asian Forum for Polar Sciences (AFoPS), an international forum of Asian polar research institutes, was established for the advancement of polar sciences among its members in 2004. The Forum has served as an important medium of Asian collective endeavors for polar affairs in human and information exchange, research collaboration, and logistics cooperation for the last decade. The historical development of the AFoPS in retrospect can be divided into four phases: inception and establishment (2003-2004), growth and expansion (2005-2007), review and restructuring (2008-2011), and achievements and further measures (2012-2014). The progress of the AFoPS has not been linear and this trend will continue into the next decades. The Forum, however, clearly made achievements in this period of time, realizing multilateral research and logistics cooperation that would have been previously unimaginable; by doing so, it has laid the foundation for the future. Responsible for a great portion of the world's polar activities, the AFoPS will rise to meet the expectations of the world by producing notable research output, initiating international cooperative programs, and supporting non-polar Asian countries with education and research collaboration. These are the tasks of the AFoPS for the next decade and they require strategy that promotes and facilitates collaboration in a practical way and draws attention of non-polar Asian countries to the polar sciences.

  13. Preparation and characterization of monodispersed PS/Ag composite microspheres through modified electroless plating

    NASA Astrophysics Data System (ADS)

    Ma, Yuehui; Zhang, Qinghua

    2012-07-01

    A modified electroless silver-plating process has been devised for the preparation of monodispersed, polystyrene/silver (PS/Ag) composite microspheres with tunable shell thickness. Tailoring was achieved by altering the concentration of the silver precursor in the plating bath. PS/Ag composite microspheres were characterized by field-emission scanning electron microscopy, ultraviolet-visible absorption, X-ray diffraction and thermogravimetric analysis. The results showed that a dense, stable and uniform silver nanoshell was formed on the surface of PS microspheres in the presence of poly(vinylpyrrolidone) and glucose. The bulk conductivity of the PS/Ag composites increased from 1.16 S/m to 3.57 × 104 S/m, corresponding to a shell thickness of 35-198 nm. The PS/Ag composite microspheres with diameters of ca. 3 μm might have great potential to be used as fillers in anisotropic conductive films because of the uniform diameter, low density and good conductivity of the microspheres.

  14. Surface Dynamics of Free PS Chains on Chemically Identical Polymer Brushes: An XPCS Study

    NASA Astrophysics Data System (ADS)

    Ugur, Gokce; Akgun, Bulent; Jiang, Zhang; Narayanan, Suresh; Brittain, William J.; Foster, Mark D.

    2009-03-01

    We found no relaxation of fluctuations of the brush surfaces within the range of time (0.2 -1100 s) and length scale (0.6-3 um) studied by X-ray photon correlation spectroscopy(XPCS). This is true for PS brushes of thicknesses of 9 - 101 nm and grafting density of 0.12-0.6 chains/nm^2 at temperatures up to 130C above bulk Tg. Results on the dynamics of a layer of untethered 2.2k PS chains on top of a PS brush surface show that placing the PS chains atop the brush dramatically slows down the surface relaxations of the film surface. As the ratio of the thickness of the layer of untethered chains to the thickness of the highly dense brush drops below ˜0.5, the surface relaxations become too slow to be observed readily with XPCS. Reducing grafting density of the underlying brush markedly slows the surface dynamics. The surface dynamics of the layer of ``free'' PS chains are coupled with those of the underlying brush.

  15. Proteomic response of Rhizoctonia solani GD118 suppressed by Paenibacillus kribbensis PS04.

    PubMed

    Wang, Liuqing; Liu, Mei; Liao, Meide

    2014-12-01

    Rice sheath blight, caused by Rhizoctonia solani, is considered a worldwide destructive rice disease and leads to considerable yield losses. A bio-control agent, Paenibacillus kribbensis PS04, was screened to resist against the pathogen. The inhibitory effects were investigated (>80 %) by the growth of the hyphae. Microscopic observation of the hypha structure manifested that the morphology of the pathogenic mycelium was strongly affected by P. kribbensis PS04. To explore essentially inhibitory mechanisms, proteomic approach was adopted to identify differentially expressed proteins from R. solani GD118 in response to P. kribbensis PS04 using two-dimensional gel electrophoresis. Protein profiling was used to identify 13 differential proteins: 10 proteins were found to be down-regulated while 3 proteins were up-regulated. These proteins were involved in material and energy metabolism, antioxidant activity, protein folding and degradation, and cytoskeleton regulation. Among them, material and energy metabolism was differentially regulated by P. kribbensis PS04. Protein expression was separately inhibited by the bio-control agent in oxidation resistance, protein folding and degradation, and cytoskeleton regulation. Proteome changes of the mycelium assist in understanding how the pathogen was directly suppressed by P. kribbensis PS04. PMID:25164959

  16. Miniaturized iPS-Cell-Derived Cardiac Muscles for Physiologically Relevant Drug Response Analyses.

    PubMed

    Huebsch, Nathaniel; Loskill, Peter; Deveshwar, Nikhil; Spencer, C Ian; Judge, Luke M; Mandegar, Mohammad A; B Fox, Cade; Mohamed, Tamer M A; Ma, Zhen; Mathur, Anurag; Sheehan, Alice M; Truong, Annie; Saxton, Mike; Yoo, Jennie; Srivastava, Deepak; Desai, Tejal A; So, Po-Lin; Healy, Kevin E; Conklin, Bruce R

    2016-01-01

    Tissue engineering approaches have the potential to increase the physiologic relevance of human iPS-derived cells, such as cardiomyocytes (iPS-CM). However, forming Engineered Heart Muscle (EHM) typically requires >1 million cells per tissue. Existing miniaturization strategies involve complex approaches not amenable to mass production, limiting the ability to use EHM for iPS-based disease modeling and drug screening. Micro-scale cardiospheres are easily produced, but do not facilitate assembly of elongated muscle or direct force measurements. Here we describe an approach that combines features of EHM and cardiospheres: Micro-Heart Muscle (μHM) arrays, in which elongated muscle fibers are formed in an easily fabricated template, with as few as 2,000 iPS-CM per individual tissue. Within μHM, iPS-CM exhibit uniaxial contractility and alignment, robust sarcomere assembly, and reduced variability and hypersensitivity in drug responsiveness, compared to monolayers with the same cellular composition. μHM mounted onto standard force measurement apparatus exhibited a robust Frank-Starling response to external stretch, and a dose-dependent inotropic response to the β-adrenergic agonist isoproterenol. Based on the ease of fabrication, the potential for mass production and the small number of cells required to form μHM, this system provides a potentially powerful tool to study cardiomyocyte maturation, disease and cardiotoxicology in vitro. PMID:27095412

  17. Surface tailored PS/TiO2 composite nanofiber membrane for copper removal from water.

    PubMed

    Wanjale, Santosh; Birajdar, Mallinath; Jog, Jyoti; Neppalli, Ramesh; Causin, Valerio; Karger-Kocsis, József; Lee, Jonghwi; Panzade, Prasad

    2016-05-01

    Polystyrene (PS)/TiO2 composite nanofiber membranes have been fabricated by electrospinning process for Cu(2+) ions removal from water. The surface properties of the polystyrene nanofibers were modulated by introducing TiO2 nanoparticles. The contact angle of the PS nanofiber membrane was found to be decreased with increasing concentration of TiO2, depicted enhanced hydrophilicity. These membranes were highly effective in adsorbing Cu(2+) ions from water. The adsorption capacity of these membranes was found to be 522mg/g, which is significantly higher than the results reported by other researchers. This was attributed to enhanced hydrophilicity of the PS/TiO2 composite nanofiber membranes and effective adsorption property of TiO2 nanoparticles. PMID:26866887

  18. Studies of Space Charge Effects in the Proposed CERN PS2

    SciTech Connect

    Qiang, Ji; Ryne, Robert; De Maria, Riccardo; Macridin, Alexandru; Spentzouris, Panagiotis; Papaphilippou, Yannis; Wienands, Ulrich; /SLAC

    2012-06-22

    A new proton synchrotron, the PS2, is under design study to replace the current proton synchrotron at CERN for the LHC upgrade. Nonlinear space charge effects could cause significant beam emittance growth and particle losses and limit the performance of the PS2. In this paper, we report on studies of the potential space-charge effects at the PS2 using three-dimensional self-consistent macroparticle tracking codes, IMPACT, MaryLie/IMPACT, and Synergia. We will present initial benchmark results among these codes. Effects of space-charge on the emittance growth, especially due to synchrotron coupling, aperture sizes, initial painted distribution, and RF ramping scheme will also be discussed.

  19. Industry Needs Fulfilled by Patented NASA PS300 Solid Lubricant Technology

    NASA Technical Reports Server (NTRS)

    DellaCorte, Christopher

    2003-01-01

    In 1999, the NASA Glenn Research Center was awarded a patent (#5866518) for a new high-temperature solid lubricant coating material, PS300. A combination of wear-resistant metals and ceramics with solid lubricant additives, PS300 reduces friction and wear in sliding contacts from below ambient to over 650 C. This lubricant is an outgrowth of over three decades of high-temperature tribological research and was specifically developed as a shaft lubricant to protect foil air bearings used in Oil-Free turbomachinery, like gas turbines. Foil bearings are lubricated by air at high speeds but experience sliding and wear during initial startup and shut down when a lubricating film of air has not yet developed. PS300 shaft coatings have successfully lubricated foil bearings for over 100 000 cycles without wearing out.

  20. Emerging ps-TW CO{sub 2} laser technology for high energy physics applications

    SciTech Connect

    Pogorelsky, I.V.

    1998-02-01

    A brief overview of laser acceleration techniques and a comparative analysis of the picosecond terawatt (ps-TW) CO{sub 2} laser technology versus T{sup 3} solid state lasers for prospective HEP applications. Special attention is given to two laser accelerator schemes. The first one is the far-field staged laser accelerator, STELLA, which is under exploration at the ATF using a CO{sub 2} laser. The second is a laser wakefield accelerator where ps-TW CO{sub 2} lasers have a great potential. Inverse to the laser accelerator, a prospective monochromatic x-ray source feasible at the ATF will also utilize a 50 MeV subpicosecond electron beam and the first ps-TW CO{sub 2} laser, PITER I.

  1. Controllable fabrication of PS/Ag core-shell-shaped nanostructures

    PubMed Central

    2012-01-01

    In this paper, based on the previous steps, a facile in situ reduction method was developed to controllably prepare polystyrene/Ag (PS/Ag) core-shell-shaped nanostructures. The crucial procedure includes surface treatment of polystyrene core particles by cationic polyelectrolyte polyethyleneimine, in situ formation of Ag nanoparticles, and immobilization of the Ag nanoparticles onto the surface of the polystyrene colloids via functional group NH from the polyethyleneimine. The experimental parameters, such as the reaction temperature, the reaction time, and the silver precursors were optimized for improvement of dispersion and Ag coat coverage of the core-shell-shaped nanostructures. Ultimately, the optimum parameters were obtained through a series of experiments, and well-dispersed, uniformly coated PS/Ag core-shell-shaped nanostructures were successfully fabricated. The formation mechanism of the PS/Ag core-shell-shaped nanostructures was also explained. PMID:23092195

  2. Synthesis and characterization of MnPS{sub 3} for hydrogen sorption

    SciTech Connect

    Ismail, N.; Temerk, Y.M.; El-Meligi, A.A.; Badr, M.A.; Madian, M.

    2010-05-15

    Single phase MnPS{sub 3} powder was prepared by solid state reaction between Mn, S and P carried out at 650 deg. C in evacuated silica tube. The structure, morphology and sorption characteristics of the prepared solid were investigated. The results revealed that the obtained MnPS{sub 3} compound was capable of adsorbing 3.5 wt% hydrogen at -193 deg. C and a pressure of 30 bar. Little amount of hydrogen (0.07 wt%) was adsorbed at room temperature. The hydrogen adsorption/desorption cycles at various temperatures did not result in irreversible chemical structural changes of the MnPS{sub 3} compound, but the microstructure after hydrogen cycling diminished and became finer. - Graphical abstract: Atomic building of MPS{sub 3}

  3. PsOr1, a potential target for RNA interference-based pest management.

    PubMed

    Zhao, Y Y; Liu, F; Yang, G; You, M S

    2011-02-01

    Insect pests cause billions of dollars in agricultural losses, and attempts to kill them have resulted in growing threats from insecticide resistance, dietary pesticide pollution and environmental destruction. New approaches to control refractory insect pests are therefore needed. The host-plant preferences of insect pests rely on olfaction and are mediated via a seven transmembrane-domain odorant receptor (Or) family. The present study reports the cloning and characterization of PsOr1, the first candidate member of the Or gene family from Phyllotreta striolata, a devastating beetle pest that causes damage worldwide. PsOr1 is remarkably well conserved with respect to other insect orthologues, including DmOr83b from Drosophila melanogaster. These insect orthologues form an essential non-conventional Or sub-family and may play an important and generalized role in insect olfaction. We designed double-stranded (ds) RNA directly against the PsOr1 gene and exploited RNA interference (RNAi) to control P. striolata. The chemotactic behavioural measurements showed that adult beetles were unable to sense the attractant or repellent odour stimulus after microinjection of dsRNA against PsOr1. Reverse Transcription (RT)-PCR analysis showed specific down-regulation of mRNA transcript levels for this gene. Furthermore, host-plant preference experiments confirmed that silencing PsOr1 by RNAi treatment impaired the host-plant preferences of P. striolata for cruciferous vegetables. These results demonstrate that this insect control approach of using RNAi to target PsOr1 and its orthologues might be effective in blocking host-plant-seeking behaviours in diverse insect pests. The results also support the theory that this unique receptor type plays an essential general role in insect olfaction. PMID:20854479

  4. A high-linearity and high-resolution delay line structure with a calibration algorithm in delay-based LINC transmitters

    NASA Astrophysics Data System (ADS)

    Yue, Han; Shushan, Qiao; Yong, Hei

    2016-01-01

    In order to overcome the bottleneck of low linearity and low resolution, an improved delay line structure is proposed with a calibration algorithm to conquer PVT (process, voltage and temperature) variations for an all-digital design. The chip is implemented in 0.13 μm CMOS technology. Measurement results show that the proposed structure with the calibration algorithm can evidently improve the linearity and resolution of the delay line. The delay resolution is 2 ps and the root mean square jitter of the delay is 4.71 ps, leading to an error vector magnitude enhancement of 1.32 dB.

  5. Influence of external factors on optical parameters in Cu6PS5I thin films

    NASA Astrophysics Data System (ADS)

    Studenyak, Ihor P.; Bendak, Andrii V.; Demko, Pavlo Yu.; Studenyak, Viktor I.; Izai, Vitalii Yu.; Vorokhta, Mykhailo; Matolin, Vladimir; Kúš, Peter; Lisý, Vladimir; Komada, Paweł; Kashaganova, Gulzhan

    2015-12-01

    Cu6PS5I superionic thin films were deposited onto silicate glass substrates by non-reactive radio frequency magnetron sputtering. Optical transmission spectra of annealed and implanted by sulphur and phosphorous thin films were investigated. In the temperature interval 77-300 K the temperature behavior of optical absorption spectra and dispersion of refractive index of annealed films as well as the influence of ionic implantation on spectra and parameters of exponential absorption edge were studied. Temperature dependences of optical pseudogap, Urbach energy and refractive index of annealed and implanted Cu6PS5I thin films were analysed.

  6. The death of the four "P"s: a premature obituary.

    PubMed

    MacStravic, S

    2000-01-01

    To paraphrase Mark Twain the report of the demise of the four "P"s has been greatly exaggerated. While new concepts such as the four "R"s of relevance, response, relationships, and results may add value, the four "P"s remain essential. Moreover, health care marketing can benefit from the addition of a fifth "P," Prompting customers to adopt and repeat behaviors that benefit them, and a fifth "R," Reminding customers of the health and quality-of-life benefits they have gained from health care plans and providers. PMID:11209475

  7. MiPS (Mi Prostate Score Urine test) — EDRN Public Portal

    Cancer.gov

    The MiPS assay is a multiplex analysis of T2-ERG gene fusion, PCA3, and serum PSA (KLK3). It is commercially available through the University of Michigan MLabs. The MiPS assay tests for the presence of two prostate cancer biomarkers: a piece of RNA made from the PCA3 gene, found to be overactive in 95 percent of all prostate cancers, and another RNA marker that is found only when TMPRSS2 and ERG abnormally fuse. TMPRSS2:ERG, or T2-ERG, is a strong indicator of prostate cancer.

  8. Thermal response of polystyrene/poly methyl methacrylate (PS/PMMA) polymeric blends

    NASA Astrophysics Data System (ADS)

    Mathur, Vishal; Sharma, Kananbala

    2016-02-01

    The present paper reports the investigationsto evaluate thermal behavior of polystyrene/poly methyl methacrylate (PS/PMMA) polymeric blends, prepared at different compositions through solution casting method. The glass transition temperatures have been obtained using dynamic mechanical analyzer. Simultaneous measurements of temperature dependentthermal transport properties (thermal conductivity and thermal diffusivity) have been made using Hot Disk Thermal Constants Analyzer based on transient plane source. The study reveals that blending of PS with PMMA leads to different phase morphologies corresponding to different composition range which further affects the thermal performance of respective blends.

  9. Ethics and the 7 `P`s` of computer use policies

    SciTech Connect

    Scott, T.J.; Voss, R.B.

    1994-12-31

    A Computer Use Policy (CUP) defines who can use the computer facilities for what. The CUP is the institution`s official position on the ethical use of computer facilities. The authors believe that writing a CUP provides an ideal platform to develop a group ethic for computer users. In prior research, the authors have developed a seven phase model for writing CUPs, entitled the 7 P`s of Computer Use Policies. The purpose of this paper is to present the model and discuss how the 7 P`s can be used to identify and communicate a group ethic for the institution`s computer users.

  10. 10-GHz, 1.3-ps erbium fiber laser employing soliton pulse shortening

    NASA Astrophysics Data System (ADS)

    Carruthers, Thomas F.; Duling, Irl N., III

    1996-12-01

    An actively mode-locked single-polarization erbium fiber laser modulated at 10 GHz utilizes intracavity soliton formation to produce 1.3-ps pulses, well below the Kuizenga-Siegman limit, without passive mode locking. The observed degree of pulse shortening agrees with the predictions of recently developed soliton laser models. The pulse dropout ratio was measured to be less than 10-12 , and the rms amplitude and phase jitter are less than 1.1% and 0.16 ps, respectively.

  11. Comparison of soft and hard tissue ablation with sub-ps and ns pulse lasers

    SciTech Connect

    Da Silva, L.B.; Stuart, B.C.; Celliers, P.M.; Feit, M.D.; Glinsky, M.E.; Heredia, N.J.; Herman, S.; Lane, S.M.; London, R.A.; Matthews, D.L.; Perry, M.D.; Rubenchik, A.M.; Chang, T.D.; Neev, J.

    1996-05-01

    Tissue ablation with ultrashort laser pulses offers several unique advantages. The nonlinear energy deposition is insensitive to tissue type, allowing this tool to be used for soft and hard tissue ablation. The localized energy deposition lead to precise ablation depth and minimal collateral damage. This paper reports on efforts to study and demonstrate tissue ablation using an ultrashort pulse laser. Ablation efficiency and extent of collateral damage for 0.3 ps and 1000 ps duration laser pulses are compared. Temperature measurements of the rear surface of a tooth section is also presented.

  12. Complete genome sequence of the plant growth-promoting endophyte Burkholderia phytofirmans strain PsJN.

    PubMed

    Weilharter, Alexandra; Mitter, Birgit; Shin, Maria V; Chain, Patrick S G; Nowak, Jerzy; Sessitsch, Angela

    2011-07-01

    Burkholderia phytofirmans PsJN(T) is able to efficiently colonize the rhizosphere, root, and above-ground plant tissues of a wide variety of genetically unrelated plants, such as potatoes, canola, maize, and grapevines. Strain PsJN shows strong plant growth-promoting effects and was reported to enhance plant vigor and resistance to biotic and abiotic stresses. Here, we report the genome sequence of this strain, which indicates the presence of multiple traits relevant for endophytic colonization and plant growth promotion. PMID:21551308

  13. The 80 kV electrostatic wire septum for AmPS

    NASA Astrophysics Data System (ADS)

    Vanderlinden, A.; Bijleveld, J. H. M.; Rookhuizen, H. Boer; Bruinsma, P. J. T.; Heine, E.; Lassing, P.; Prins, E.

    The characteristics of the wire septum for the Amsterdam Pulse Stretcher (AmPS) are summarized. In the extraction process of the AmPS the extracted beam is intercepted from the circulating beam by the 1 m long electrostatic wire septum. For a bending angle of 4.4 mrad, the maximum anode voltage is 80 kV. The system developed consists of a wire spacing of 0.65 mm between tungsten wires of 50 micrometers diameter. Stainless steel spring wires, bent in a half cylindrical carrier, stretch the septum wires two by two. Prototype tests were successful up to an anode voltage of 120 kV.

  14. Sub-100-ps structural dynamics of horse heart myoglobin probed by time-resolved X-ray solution scattering

    NASA Astrophysics Data System (ADS)

    Oang, Key Young; Kim, Kyung Hwan; Jo, Junbeom; Kim, Youngmin; Kim, Jong Goo; Kim, Tae Wu; Jun, Sunhong; Kim, Jeongho; Ihee, Hyotcherl

    2014-10-01

    Here we report sub-100-ps structural dynamics of horse heart myoglobin revealed by time-resolved X-ray solution scattering. By applying the time-slicing scheme to the measurement and subsequent deconvolution, we investigate the protein structural dynamics that occur faster than the X-ray temporal pulse width of synchrotrons (∼100 ps). The singular value decomposition analysis of the experimental data suggests that two structurally distinguishable intermediates are formed within 100 ps. In particular, the global structural change occurring on the time scale of 70 ps is identified.

  15. Effect of cross-link density and hydrophilicity of PU on blood compatibility of hydrophobic PS/hydrophilic PU IPNs.

    PubMed

    Roh, H W; Song, M J; Han, D K; Lee, D S; Ahn, J H; Kim, S C

    1999-01-01

    To investigate the effect of the hydrophilic and hydrophobic microdomain structure on blood compatibility, a series of interpenetrating polymer networks (IPNs) composed of hydrophilic polyurethane (PU) and hydrophobic polystyrene (PS) was prepared. One series was prepared with varying cross-link densities of each network, the other with varying hydrophilicity of the PU component. All PU/PS IPNs exhibited microphase-separated structures that had dispersed PS domains in the continuous PU matrix. The domain size decreased with decreasing the hydrophilicity of the PU component and increasing the cross-link density of each network. As the cross-link density and hydrophobicity of the PU component was increased, an inward shift of Tgs was observed, which was due to the decrease in phase separation between the hydrophobic PS component and hydrophilic PU component. In the in vitro platelet adhesion test, as the microdomain size of PU/PS IPN surface decreased, the number of adhered platelets on the PU/PS IPN surface was reduced and deformation of the adhered platelets decreased. It could be concluded that blood compatibility of PU/PS IPN was mainly affected by the degree of mixing between PU and PS component, which was reflected by the domain size of PS rich phase. PMID:10091927

  16. Ataxia telangiectasia derived iPS cells show preserved x-ray sensitivity and decreased chromosomal instability.

    PubMed

    Fukawatase, Yoshihiro; Toyoda, Masashi; Okamura, Kohji; Nakamura, Ken-ichi; Nakabayashi, Kazuhiko; Takada, Shuji; Yamazaki-Inoue, Mayu; Masuda, Akira; Nasu, Michiyo; Hata, Kenichiro; Hanaoka, Kazunori; Higuchi, Akon; Takubo, Kaiyo; Umezawa, Akihiro

    2014-01-01

    Ataxia telangiectasia is a neurodegenerative inherited disease with chromosomal instability and hypersensitivity to ionizing radiation. iPS cells lacking ATM (AT-iPS cells) exhibited hypersensitivity to X-ray irradiation, one of the characteristics of the disease. While parental ataxia telangiectasia cells exhibited significant chromosomal abnormalities, AT-iPS cells did not show any chromosomal instability in vitro for at least 80 passages (560 days). Whole exome analysis also showed a comparable nucleotide substitution rate in AT-iPS cells. Taken together, these data show that ATM is involved in protection from irradiation-induced cell death. PMID:24970375

  17. Sub-100-ps structural dynamics of horse heart myoglobin probed by time-resolved X-ray solution scattering

    PubMed Central

    Oang, Key Young; Kim, Kyung Hwan; Jo, Junbeom; Kim, Youngmin; Kim, Jong Goo; Kim, Tae Wu; Jun, Sunhong; Kim, Jeongho; Ihee, Hyotcherl

    2015-01-01

    Here we report sub-100-ps structural dynamics of horse heart myoglobin revealed by time-resolved X-ray solution scattering. By applying the time-slicing scheme to the measurement and subsequent deconvolution, we investigate the protein structural dynamics that occur faster than the X-ray temporal pulse width of synchrotrons (~100 ps). The singular value decomposition analysis of the experimental data suggests that two structurally distinguishable intermediates are formed within 100 ps. In particular, the global structural change occurring on the time scale of 70 ps is identified. PMID:25678733

  18. SED-Machine Classification of PSN J09430082+3146486 and PS1-14xx

    NASA Astrophysics Data System (ADS)

    Konidaris, N.; Quimby, R.; Ben-Ami, S.; Ngeow, C.; Ofek, E.; Ritter, A.

    2014-05-01

    We obtained optical spectra (4000-10000 A) of PSN J09430082+3146486 and PS1-14xx using the SED-Machine mounted on the Palomar 1.5-m Telescope. We report the following classifications using superfit (Howell et al. ...

  19. Exploring the Potential of LiPS Instruction for Beginning Readers

    ERIC Educational Resources Information Center

    McIntyre, Laureen; Protz, Susan; McQuarrie, Lynn

    2008-01-01

    The purpose of this study was to determine if phonemic awareness skills improved for first grade students classified as at-risk whose teachers used the Lindamood Phoneme Sequencing Program (LiPS; Lindamood & Lindamood, 1998). Students' scores on a Kindergarten screening tool (Learning Disabilities Working Committee-LDWC, 2005) were compared to…

  20. Sulfide response analysis for sulfide control using a pS electrode in sulfate reducing bioreactors.

    PubMed

    Villa-Gomez, D K; Cassidy, J; Keesman, K J; Sampaio, R; Lens, P N L

    2014-03-01

    Step changes in the organic loading rate (OLR) through variations in the influent chemical oxygen demand (CODin) concentration or in the hydraulic retention time (HRT) at constant COD/SO4(2-) ratio (0.67) were applied to create sulfide responses for the design of a sulfide control in sulfate reducing bioreactors. The sulfide was measured using a sulfide ion selective electrode (pS) and the values obtained were used to calculate proportional-integral-derivative (PID) controller parameters. The experiments were performed in an inverse fluidized bed bioreactor with automated operation using the LabVIEW software version 2009(®). A rapid response and high sulfide increment was obtained through a stepwise increase in the CODin concentration, while a stepwise decrease to the HRT exhibited a slower response with smaller sulfide increment. Irrespective of the way the OLR was decreased, the pS response showed a time-varying behavior due to sulfide accumulation (HRT change) or utilization of substrate sources that were not accounted for (CODin change). The pS electrode response, however, showed to be informative for applications in sulfate reducing bioreactors. Nevertheless, the recorded pS values need to be corrected for pH variations and high sulfide concentrations (>200 mg/L). PMID:24361702

  1. Deposition of BACE-1 Protein in the Brains of APP/PS1 Double Transgenic Mice

    PubMed Central

    Luo, Gang; Xu, Hongxia; Huang, Yinuo; Mo, Dapeng; Song, Ligang; Jia, Baixue; Wang, Bo; Jin, Zhanqiang; Miao, Zhongrong

    2016-01-01

    The main causes of Alzheimer's disease remain elusive. Previous data have implicated the BACE-1 protein as a central player in the pathogenesis of Alzheimer's disease. However, many inhibitors of BACE-1 have failed during preclinical and clinical trials for AD treatment. Therefore, uncovering the exact role of BACE-1 in AD may have significant impact on the future development of therapeutic agents. Three- and six-month-old female APP/PS1 double transgenic mice were used to study abnormal accumulation of BACE-1 protein in brains of mice here. Immunofluorescence, immunohistochemistry, and western blot were performed to measure the distributing pattern and expression level of BACE-1. We found obvious BACE-1 protein accumulation in 3-month-old APP/PS1 mice, which had increased by the time of 6 months. Coimmunostaining results showed BACE-1 surrounded amyloid plaques in brain sections. The abnormal protein expression might not be attributable to the upregulation of BACE-1 protein, as no significant difference of protein expression was observed between wild-type and APP/PS1 mice. With antibodies against BACE-1 and CD31, we found a high immunoreactive density of BACE-1 protein on the outer layer of brain blood vessels. The aberrant distribution of BACE-1 in APP/PS1 mice suggests BACE-1 may be involved in the microvascular abnormality of AD. PMID:27294139

  2. Induced Pluripotent Stem (iPS) Cell Culture Methods and Induction of Differentiation into Endothelial Cells

    PubMed Central

    Chatterjee, Ishita; Li, Fei; Kohler, Erin E.; Rehman, Jalees; Malik, Asrar B.; Wary, Kishore K.

    2015-01-01

    Summary The studies of stem cell behavior and differentiation in a developmental context is complex, time-consuming and expensive, and for this reason, cell culture remains a method of choice for developmental and regenerative biology and mechanistic studies. Similar to ES cells, iPS cells have the ability to differentiate into endothelial cells (ECs), and the route for differentiation appears to mimic the developmental process that occurs during the formation of an embryo. Traditional EC induction methods from embryonic stem (ES) cells rely mostly on the formation the embryoid body (EB), which employs feeder or feeder-free conditions in the presence or absence of supporting cells. Similar to ES cells, iPS cells can be cultured in feeder-layer or feeder-free conditions. Here, we describe the iPS cell culture methods and induction differentiation of these cells into ECs. We use anti-mouse Flk1 and anti-mouse VE-cadherin to isolate and characterize mouse ECs, because these antibodies are commercially available and their use has been described in the literature, including by our group. The ECs produced by this method have been used by our laboratory, and we have demonstrated their in vivo potential. We also discuss how iPS cells differ in their ability to differentiate into endothelial cells in culture. PMID:25687301

  3. Spectroscopic Classification of PS15bln as a Type Ia supernova near maximum light

    NASA Astrophysics Data System (ADS)

    Piascik, A. S.; Steele, I. A.

    2015-08-01

    We conducted a spectroscopic observation of transient PS15bln at 2015-08-01T22:01:48 UT. This transient was identified by the Pan-STARRS Survey for Transients (PSST) in ATel #7857 with a discovery date 2015-07-25.

  4. Classification of PS15bpa as a post maximum Type II supernova

    NASA Astrophysics Data System (ADS)

    Piascik, A. S.; Steele, I. A.

    2015-08-01

    We conducted a spectroscopic observation of transient PS15bpa at 2015-08-06T22:11:16 UT. This transient was identified by the Pan-STARRS Survey for Transients (PSST) in ATel #7876 with a discovery date 2015-08-01.

  5. 75 FR 66734 - Proposed Voluntary Product Standard PS 2-10, Structural Plywood

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-29

    ... on a proposed revision to Voluntary Product Standard (PS) 2-04, Performance Standard for Wood-Based... assess the acceptability of wood-based structural-use panels for construction sheathing and single-floor... acceptability of wood-based structural-use panels for construction sheathing and single- floor application,...

  6. INHIBITION OF PS II PHOTOCHEMISTRY BY PAR AND UV RADIATION IN NATURAL PHYTOPLANKTON COMMUNITIES

    EPA Science Inventory

    The effects of PAR and UV radiation on PS II photochemistry were examined in natural phytoplankton communities from coastal waters off Rhode Island (USA) and the subtropical Pacific. he photochemical energy conversion efficiency, the functional absorption cross section and the ki...

  7. Solvent vapor induced morphology variation in thin films of PS-b-PLA copolymers

    NASA Astrophysics Data System (ADS)

    Foote, Lauren; Heres, Maximilian; Kinsey, Thomas; Sangoro, Joshua

    Molecular dynamics in thin films of PS-b-PLA copolymers annealed by solvent vapor annealing is investigated using broadband dielectric spectroscopy, atomic force microscopy and ellipsometry. Impact of morphology changes on molecular dynamics are analyzed. The results of this study are discussed within the framework of current understanding of morphology control of copolymer thin films.

  8. 27ps DFT Molecular Dynamics Simulation of a-maltose: A Reduced Basis Set Study.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DFT molecular dynamics simulations are time intensive when carried out on carbohydrates such as alpha-maltose, requiring up to three or more weeks on a fast 16-processor computer to obtain just 5ps of constant energy dynamics. In a recent publication [1] forces for dynamics were generated from B3LY...

  9. [Unresolved issues in the evaluation of research projects involving induced pluripotent stem cells (iPS)].

    PubMed

    Casado, María; de Lecuona, Itziar

    2013-01-01

    This paper identifies problems and analyzes those conflicts posed by the evaluation of research projects involving the collection and use of human induced pluripotent stem cells (iPS) in Spain. Current legislation is causing problems of interpretation, circular and unnecessary referrals, legal uncertainty and undue delays. Actually, this situation may cause a lack of control and monitoring, and even some paralysis in regenerative medicine and cell therapy research, that is a priority nowadays. The analysis of the current legislation and its bioethical implications, led us to conclude that the review of iPS research projects cannot be assimilated to the evaluation of research projects that involve human embryonic stem cell (hESC). In this context, our proposal is based on the review by the Research Ethics Committees and the checkout by the Spanish Comission of Guarantees for Donation and Use of Human Cells and Tissues (CGDUCTH) of human iPS cells research projects. Moreover, this article claims for a more transparent research system, by effectively articulating the Registry on Research Projects. Finally, a model of verification protocol (checklist) for checking out biomedical research projects involving human iPS cells is suggested. PMID:24868955

  10. The PS 200 catching trap: A new tool for ultra-low energy antiproton physics

    SciTech Connect

    Holzscheiter, M.H.; Dyer, P.L.; King, N.S.P.; Lizon, D.C.; Morgan, G.L.; Schauer, M.M.; Schecker, J.A.; Hoibraten, S.; Lewis, R.A.; Otto, T.; Rochet, J.

    1994-04-01

    Approximately one million antiprotons have been trapped and electron cooled in the PS200 catching trap from a single fast extracted pulse from LEAR. The system is described in detail, different extraction schemes are discussed, and possible applications of this instrument to ultra-low energy atomic and nuclear physics with antiprotons are mentioned.

  11. Lindamood Phonemic Sequencing (LiPS) [R]. What Works Clearinghouse Intervention Report

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2008

    2008-01-01

    The Lindamood Phonemic Sequencing (LiPS)[R] program (formerly called the Auditory Discrimination in Depth[R] [ADD] program) is designed to teach students skills to decode words and to identify individual sounds and blends in words. The program is individualized to meet student needs and is often used with students who have learning disabilities or…

  12. Bacteriophage-like Particles Associated with the Gene Transfer Agent of Methanococcus Voltale PS

    NASA Technical Reports Server (NTRS)

    Bertani, G.; Eiserling, F.; Pushkin, A.; Gingery, M.

    1999-01-01

    The methanogenic archaebacterium Methanococus voltae (strain PS) is known to produce a filterable, DNase resistant agent (called VTA, for voltae transfer agent), which carries very small fragments (4,400 base pairs) of bacterial DNA and is able to transduce bacterial genes between derivatives of the strain.

  13. Perceived Professional Development Needs of Teachers and Administrators in PS-12 Christian Schools

    ERIC Educational Resources Information Center

    Finn, Donald; Swezey, James; Warren, Debra

    2010-01-01

    To fulfill their religious and educational missions, PS-12 Christian schools should properly equip teachers to design and deliver instruction of the highest quality that incorporates sound pedagogical approaches. Research indicates that a key element for making this happen in classrooms is to offer professional development opportunities that…

  14. Complete Genome Sequence of Streptococcus salivarius PS4, a Strain Isolated from Human Milk

    PubMed Central

    Martín, Virginia; Maldonado-Barragán, Antonio; Jiménez, Esther; Ruas-Madiedo, Patricia; Fernández, Leónides

    2012-01-01

    Streptococcus salivarius is a commensal species commonly found in the human oropharyngeal tract. Some strains of this species have been developed for use as oral probiotics, while others have been associated with a variety of opportunistic human infections. Here, we report the complete sequence of strain PS4, which was isolated from breast milk of a healthy woman. PMID:22843595

  15. Complete genome sequence of Streptococcus salivarius PS4, a strain isolated from human milk.

    PubMed

    Martín, Virginia; Maldonado-Barragán, Antonio; Jiménez, Esther; Ruas-Madiedo, Patricia; Fernández, Leónides; Rodríguez, Juan M

    2012-08-01

    Streptococcus salivarius is a commensal species commonly found in the human oropharyngeal tract. Some strains of this species have been developed for use as oral probiotics, while others have been associated with a variety of opportunistic human infections. Here, we report the complete sequence of strain PS4, which was isolated from breast milk of a healthy woman. PMID:22843595

  16. Precision measurement of the decay rate of the negative positronium ion Ps{sup -}

    SciTech Connect

    Ceeh, Hubert; Hugenschmidt, Christoph; Schreckenbach, Klaus; Gaertner, Stefan A.; Thirolf, Peter G.; Fleischer, Frank; Schwalm, Dirk

    2011-12-15

    The negative positronium ion Ps{sup -} is a bound system consisting of two electrons and a positron. Its three constituents are pointlike leptonic particles of equal mass, which are subject only to the electroweak and gravitational force. Hence, Ps{sup -} is an ideal object in which to study the quantum mechanics of a three-body system. The ground state of Ps{sup -} is stable against dissociation but unstable against annihilation into photons. We report here on a precise measurement of the Ps{sup -} ground-state decay rate {Gamma}, which was carried out at the high-intensity NEutron induced POsitron source MUniCh (NEPOMUC) at the research reactor FRM II in Garching. A value of {Gamma}=2.0875(50) ns{sup -1} was obtained, which is three times more precise than previous experiments and in agreement with most recent theoretical predictions. The achieved experimental precision is at the level of the leading corrections in the theoretical predictions.

  17. Enhanced penetration of exogenous EPCs into brains of APP/PS1 transgenic mice

    PubMed Central

    Yuan, Xiaoyang; Mei, Bin; Zhang, Le; Zhang, Cuntai; Zheng, Miao; Liang, Huifang; Wang, Wei; Zheng, Jie; Ding, Ling; Zheng, Kai

    2016-01-01

    The aim of this study was to investigate the repair function of exogenous Endothelial progenitor cells (EPCs) for brain microvascular damage of the APP/PS1 transgenic mouse model of Alzheimer’s disease (AD). This study used a density-gradient centrifugation method to isolate mononuclear cells (MNCs) from mouse bone marrow, which were subsequently seeded and cultured. Cells were characterized by morphology and detection of the surface markers CD34 and CD133 at different time points by immunofluorescence (IF) and flow cytometry (FCM). Then, EPCs were transfected with GFP adenoviral vectors (GFP-EPCs). Wild-type (WT) and APP/PS1 transgenic mice both received GFP-EPCs injection through the tail vein, and using a PBS buffer injection as the control. Seven days later, the animals’ brain tissue was isolated. Expression of GFP was detected by quantitative polymerase chain reaction (qPCR) and western-blot (WB), while the fluorescence of GFP within the brains of mice was observed under a fluorescence microscope. Higher mRNA and protein expression of GFP, accompanied with increased green fluorescence, were detected in the brain of GFP-EPCs-injected APP/PS1 mice, as compared with GFP-EPCs-injected WT mice. The results show that the APP/PS1 transgenic mouse model of AD exhibited enhanced penetration of exogenous EPCs into brains than the WT mice. PMID:27186272

  18. Beyond the Four Ps: A Theoretical Explication and Research Agenda for Social Marketing.

    ERIC Educational Resources Information Center

    Sego, Trina

    Advocates of social marketing in the 1970s rarely went beyond discussion of the marketing 4Ps (product, place, promotion, and price) and their application to case studies. After two decades of research on social marketing, some misunderstanding of the approach persists, and a substantial theoretical base for social marketing has not been…

  19. [Towards the Clinical Application of iPS Cell Technology for the Treatment of Kidney Diseases].

    PubMed

    Osafune, Kenji

    2015-02-01

    In Japan, around 13 million adults have been estimated to suffer from chronic kidney disease (CKD), and more than 300 thousand patients with end-stage renal failure are receiving dialysis therapy, causing both medical and medicoeconomic problems. Regenerative medicine strategies using induced pluripotent stem (iPS) cells are among the candidate approaches to solve the problems. The mechanisms of kidney development and cell fate in the development of renal lineage cells have been elucidated using experimental animal models. Based on the knowledge of kidney development, intensive research has already been conducted to generate renal lineage cells from mouse embryonic stem (ES) cells, while few reports have been on studies using human iPS/ES cells. Recently, several research groups, including ours, have established methods to differentiate human iPS/ES cells into the intermediate mesoderm, an embryonic germ layer that gives rise to the kidney, and embryonic renal progenitors. Some reports also described the formation of three-dimensional renal tissues, such as renal tubules and glomeruli. Continued efforts are required to elucidate the mechanisms of kidney development and generate renal cells or tissues from human iPS cells, which could open up the new research avenues towards clinical application and practical use to overcome problems associated with kidney disease, such as human embryology, cell therapy, toxicology, drug discovery, and disease modeling. PMID:26529981

  20. Improved Thermal Cycling Durability of Thermal Barrier Coatings Manufactured by PS-PVD

    NASA Astrophysics Data System (ADS)

    Rezanka, S.; Mauer, G.; Vaßen, R.

    2014-01-01

    The plasma spray-physical vapor deposition (PS-PVD) process is a promising method to manufacture thermal barrier coatings (TBCs). It fills the gap between traditional thermal spray processes and electron beam physical vapor deposition (EB-PVD). The durability of PS-PVD manufactured columnar TBCs is strongly influenced by the compatibility of the metallic bondcoat (BC) and the ceramic TBC. Earlier investigations have shown that a smooth BC surface is beneficial for the durability during thermal cycling. Further improvements of the bonding between BC and TBC could be achieved by optimizing the formation of the thermally grown oxide (TGO) layer. In the present study, the parameters of pre-heating and deposition of the first coating layer were investigated in order to adjust the growth of the TGO. Finally, the durability of the PS-PVD coatings was improved while the main advantage of PS-PVD, i.e., much higher deposition rate in comparison to EB-PVD, could be maintained. For such coatings, improved thermal cycling lifetimes more than two times higher than conventionally sprayed TBCs, were measured in burner rigs at ~1250 °C/1050 °C surface/substrate exposure temperatures.

  1. Genome Sequence of Lactobacillus gastricus PS3, a Strain Isolated from Human Milk

    PubMed Central

    Martín, Virginia; Cárdenas, Nivia; Jiménez, Esther; Maldonado, Antonio; Rodríguez, Juan Miguel

    2013-01-01

    Lactobacillus gastricus is a mostly unknown lactobacilli species associated with mucosal surfaces. We present the draft annotated genome sequence of L. gastricus strain PS3, isolated from a human milk sample, to provide new insights into its biology and to characterize those genes related to advantageous technological and beneficial properties. PMID:23846278

  2. Lindamood Phoneme Sequencing[R] (LiPS[R]). What Works Clearinghouse Intervention Report

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2010

    2010-01-01

    The "Lindamood Phoneme Sequencing"[R] ("LiPS"[R]) program (formerly called the "Auditory Discrimination in Depth"[R] ["ADD"] program) is designed to teach students the skills they need to decode words and to identify individual sounds and blends in words. Thirty-one studies reviewed by the What Works Clearinghouse (WWC) investigated the effects of…

  3. Orbit, optics and chromaticity correction for PS2 negative momentum compaction lattices

    SciTech Connect

    Papaphilippou,Y.; Barranco, J.; Bartmann, W.; Benedikt, M.; Carli, C.; de Maria, R.; Peggs, S.; Trbojevic, D.

    2009-05-04

    The effect of magnet misalignments in the beam orbit and linear optics functions are reviewed and correction schemes are applied to the negative momentum compaction lattice of PS2. Chromaticity correction schemes are also proposed and tested with respect to off-momentum optics properties. The impact of the correction schemes in the dynamic aperture of the lattice is finally evaluated.

  4. Quantifying the remineralization of artificial caries lesions using PS-OCT

    NASA Astrophysics Data System (ADS)

    Jones, Robert S.; Fried, Daniel

    2006-02-01

    New optical imaging methods are needed to determine whether caries lesions (tooth decay) are active and progressing or have become remineralized and arrested and are no longer progressing. The objective of this study was to use Polarization Sensitive Optical Coherence Tomography (PS-OCT) to image the fluoride enhanced remineralization of artificial enamel lesions. Artificial lesions were created by an acetate buffer on smooth enamel surfaces and were exposed for 20 days to a 2 ppm fluoride containing remineralization solution. PS-OCT images revealed the presence of a low scattering surface zone after the artificial lesions were remineralized. These samples displayed intact nondepolarizing surface zones when analyzed with Polarized Light Microscopy (PLM). No statistical difference in lesion depth before and after remineralization was found with both PS-OCT and PLM. The remineralized lesions showed a significant decrease in the overall integrated reflectivity compared with the demineralized lesions. Digital Microradiography confirmed the increase in mineral volume of the remineralized surface zone. This study determined that PS-OCT can image the restoration of the surface zone enamel after fluoride-enhanced remineralization of artificial in vitro dental caries.

  5. Automated detection of remineralization in simulated enamel lesions with PS-OCT

    NASA Astrophysics Data System (ADS)

    Lee, Robert C.; Darling, Cynthia L.; Fried, Daniel

    2014-02-01

    Previous in vitro and in vivo studies have demonstrated that polarization-sensitive optical coherence tomography (PS-OCT) can be used to nondestructively image the subsurface structure and measure the thickness of the highly mineralized transparent surface zone of caries lesions. There are structural differences between active lesions and arrested lesions, and the surface layer thickness may correlate with activity of the lesion. The purpose of this study was to develop a method that can be used to automatically detect and measure the thickness of the transparent surface layer in PS-OCT images. Automated methods of analysis were used to measure the thickness of the transparent layer and the depth of the bovine enamel lesions produced using simulated caries models that emulate demineralization in the mouth. The transparent layer thickness measured with PS-OCT correlated well with polarization light microscopy (PLM) measurements of all regions (r2=0.9213). This study demonstrates that PS-OCT can automatically detect and measure thickness of the transparent layer formed due to remineralization in simulated caries lesions.

  6. 7 CFR 1753.7 - Plans and specifications (P&S).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... standards and specifications listed in 7 CFR part 1755 shall be included in the P&S. When RUS has not... is included in the construction. (b) 7 CFR 1755.93 provides a list of the RUS forms of...) The insurance provision shall provide coverage as required by 7 CFR 1788. (ii) A contractor's...

  7. 7 CFR 1753.7 - Plans and specifications (P&S).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... standards and specifications listed in 7 CFR part 1755 shall be included in the P&S. When RUS has not... is included in the construction. (b) 7 CFR 1755.93 provides a list of the RUS forms of...) The insurance provision shall provide coverage as required by 7 CFR 1788. (ii) A contractor's...

  8. Versatile properties of an exopolysaccharide R-PS18 produced by Rhizobium sp. PRIM-18.

    PubMed

    Priyanka, P; Arun, A B; Ashwini, P; Rekha, P D

    2015-08-01

    Exopolysaccharides (EPS) produced by bacteria have attracted scientific and industrial attention due to their multifunctional properties and relatively easier production. In this study, an EPS viz., R-PS18 produced by Rhizobium sp. PRIM-18 was characterized and its functional properties were assessed. Cell proliferative and in vitro wound healing activities of the EPS were established using human dermal fibroblast (HDF) cells. The isolate produced 2.1 g L(-1) purified EPS (molecular weight 9.33×10(6) Da) comprising of glucose, galactose, and mannose (6.1:1.8:1). Viscosity of 0.25% solution was 23.4 mPa s (shear rate 75 s(-1)) and it showed pseudoplastic and thixotropic behavior. High emulsification, iron chelation, and superoxide scavenging abilities were also observed. Significant increase in HDF cell proliferation and wound healing in vitro was achieved by R-PS18 treatment. Sulfation of R-PS18 significantly enhanced the cell proliferative and wound healing activities. In conclusion, these findings indicate potential applications of R-PS18. PMID:25933542

  9. PS-b-PDMS Block Copolymer Thin Film: Pattern Formation and Phase Behavior

    NASA Astrophysics Data System (ADS)

    Hsieh, I.-Fan; Cheng, Stephen Z. D.; Department of Polymer Science, The University of Akron Team

    2011-03-01

    Recently, block copolymer thin films attract great attention due to their potential applications in surface nano-lithography. In our work, PS- b -PDMS with cylinder morphology is chosen due to extremely large χ value between two blocks. Besides, PS- b -PDMS can be transformed into silicon oxide under UV/O3 exposure and a layer of silicon oxide with the self-assembled block copolymer patterns can be made. By utilizing the PGMEA as solvent, we can easily obtain sphere morphology in cylindrical composition block copolymer by preserved block copolymer solution morphology during film formation. Furthermore, in thermal annealing process, the phase behavior of the PS- b -PDMS thin film is strongly affects by molecular weight, film thickness and annealing temperature. In larger-molecular-weight PS- b -PDMS, we only observed spherical domains rearrangement and without morphology transition between sphere and cylinder due to high energy barrier, whereas, in the case of smaller-molecular-weight polymer, depending on the film thickness and annealing temperature, its thin film morphology transits between sphere and cylinder alternatively, which is similar to what we found in solvent annealing.

  10. PS-b-PDMS Block Copolymer Thin Film: Pattern Formation and Phase Behavior

    NASA Astrophysics Data System (ADS)

    Hsieh, I.-Fan; Cheng, Stephen Z. D.; Chen, Feng; Fu, Qiang

    2010-03-01

    Recently, block copolymer thin films are of great interest for their applications in surface patterning, and thin films of diblock copolymers with cylindrical microdomains normal to the surface are more attractive due to the tenability of large aspect ratios of the cylindrical microdomains. Within various kind of block copolymer, PS-b-PDMS is chosen due to an extremely large χ value between PS and PDMS. PS-b-PDMS can be transformed into silicon oxide under UV/O3 exposure, and a layer of silicon oxide with the self-assembled block copolymer patterns can be made. In our work, utilizing PGMEA as solvent and its vapor as spin casting atmosphere, we found an effective approach to obtain the PDMS cylinders oriented normal to the substrate. Furthermore, during benzene solvent annealing, PDMS cylinders' orientation transfers from perpendicular to parallel and then back to perpendicular again. By changing the cylinders orientation alternatively, the lateral order of cylinder packing gradually improved. By investigating this morphology evolution, the mechanism and free energy pathway for PS-b-PDMS thin film morphology transition during solvent annealing can be constructed.

  11. Investigation of Thermal Processing on the Properties of PS304: A Solid Lubricant Coating

    NASA Technical Reports Server (NTRS)

    Benoy, Patricia A.; Williams, Syreeta (Technical Monitor)

    2002-01-01

    The effect of thermal processing on PS304, a solid lubricant coating, was investigated. PS304 is a plasma sprayed solid lubricant consisting of 10% Ag and 10% BaF2 and CaF2 in a eutectic mixture for low and high temperature lubricity respectively. In addition, PS304 contains 20% Cr2O3 for increased hardness and 60% NiCr which acts as a binder. All percents are in terms of weight not volume. Previous research on thermal processing (NAG3-2245) of PS304 revealed that substrate affected both the pre- and post-anneal hardness of the plasma spray coating. The objective of this grant was to both quantify this effect and determine whether the root cause was an artifact of the substrate or an actual difference in hardness due to interaction between the substrate and the coating. In addition to clarifying past research developments new data was sought in terms of coating growth due to annealing.

  12. Detection of ultrastructural changes in genetically altered and exercised skeletal muscle using PS-OCT

    NASA Astrophysics Data System (ADS)

    Pasquesi, James J.; Schlachter, Simon C.; Boppart, Marni D.; Chaney, Eric; Kaufman, Stephen J.; Boppart, Stephen A.

    2006-02-01

    Birefringence of skeletal muscle has been associated with the ultrastructure of individual sarcomeres, specifically the arrangement of A-bands corresponding to the thick myosin filaments. Murine skeletal muscle (gastrocnemius) was imaged with a fiber-based PS-OCT imaging system to determine the level of birefringence present in the tissue under various conditions. In addition to muscle controls from wild-type mice, muscle from abnormal mice included: genetically-modified (mdx) mice which model human muscular dystrophy, transgenic mice exhibiting an overexpression of integrin (α7β1), and transgenic integrin (α7β1)knockout mice. Comparisons were also made between rested and exercised muscles to determine the effects of exercise on muscle birefringence for each of these normal and abnormal conditions. The PS-OCT images revealed that the presence of birefringence was similar in the rested muscle with dystrophy-like features (i.e., lacking the structural protein dystrophin - mdx) and in the integrin (α7β1)knockout muscle when compared to the normal (wild-type) control. However, exercising these abnormal muscle tissues drastically reduced the presence of birefringence detected by the PS-OCT system. The muscle exhibiting an overexpression of integrin (α7β1) remained heavily birefringent before and after exercise, similar to the normal (wild-type) muscle. These results suggest that there is a distinct relationship between the degree of birefringence detected using PS-OCT and the sarcomeric ultrastructure present within skeletal muscle.

  13. Enhanced penetration of exogenous EPCs into brains of APP/PS1 transgenic mice.

    PubMed

    Yuan, Xiaoyang; Mei, Bin; Zhang, Le; Zhang, Cuntai; Zheng, Miao; Liang, Huifang; Wang, Wei; Zheng, Jie; Ding, Ling; Zheng, Kai

    2016-01-01

    The aim of this study was to investigate the repair function of exogenous Endothelial progenitor cells (EPCs) for brain microvascular damage of the APP/PS1 transgenic mouse model of Alzheimer's disease (AD). This study used a density-gradient centrifugation method to isolate mononuclear cells (MNCs) from mouse bone marrow, which were subsequently seeded and cultured. Cells were characterized by morphology and detection of the surface markers CD34 and CD133 at different time points by immunofluorescence (IF) and flow cytometry (FCM). Then, EPCs were transfected with GFP adenoviral vectors (GFP-EPCs). Wild-type (WT) and APP/PS1 transgenic mice both received GFP-EPCs injection through the tail vein, and using a PBS buffer injection as the control. Seven days later, the animals' brain tissue was isolated. Expression of GFP was detected by quantitative polymerase chain reaction (qPCR) and western-blot (WB), while the fluorescence of GFP within the brains of mice was observed under a fluorescence microscope. Higher mRNA and protein expression of GFP, accompanied with increased green fluorescence, were detected in the brain of GFP-EPCs-injected APP/PS1 mice, as compared with GFP-EPCs-injected WT mice. The results show that the APP/PS1 transgenic mouse model of AD exhibited enhanced penetration of exogenous EPCs into brains than the WT mice. PMID:27186272

  14. Swift follow-up observation of the optical transient PS16ccm

    NASA Astrophysics Data System (ADS)

    Kong, A. K. H.

    2016-07-01

    We report on a Swift follow-up observation of the optical transient PS16ccm (= Gaia16ara; ATel #9226). The field of this source was observed with Swift on 2016-07-13 04:36 UT for a total exposure of about 3 ks. No X-ray source was found at the optical position.

  15. PS341 inhibits hepatocellular and colorectal cancer cells through the FOXO3/CTNNB1 signaling pathway

    PubMed Central

    Yang, Zhao; Liu, Shengwu; Zhu, Mingao; Zhang, Hong; Wang, Ji; Xu, Qian; Lin, Kaisu; Zhou, Xiumin; Tao, Min; Li, Chong; Zhu, Hong

    2016-01-01

    Hepatocellular carcinoma (HCC) and colorectal cancer (CRC) are among the most common cancers across the world. Particularly, a large number of patients with CRC also have liver metastasis. Currently, there are just a few targeted drugs against these two kinds of tumors which can only benefit a very small population of patients. Therefore, the need of more effective therapeutic drugs or strategies for these two types of cancers is urgent. PS341 (Bortezomib) is the first proteasome inhibitor drug which has been approved in clinical treatment for multiple myeloma. Here we demonstrated that PS341 negatively regulated HCC and CRC both in vitro and in vivo, including the inhibition of cell proliferation, epithelial-mesenchymal transition (EMT), the expression of stemness-related genes, cell migration and invasiveness. Mechanically, PS341 upregulated the expression of FOXO3, which inhibited the transcriptional activation of CTNNB1. The downregualtion of CTNNB1 led to apoptosis, cell cycle arrest, and the inhibition of migration, invasion, self-renewal and tumor formation of these two cancer types. In sum, our findings shed light on the PS341 mediated targeted therapy against both HCC and CRC in the future. PMID:26915315

  16. 7 CFR 1753.7 - Plans and specifications (P&S).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... is included in the construction. (b) 7 CFR 1755.93 provides a list of the RUS forms of... standards and specifications listed in 7 CFR part 1755 shall be included in the P&S. When RUS has not...) The insurance provision shall provide coverage as required by 7 CFR 1788. (ii) A contractor's...

  17. 7 CFR 1753.7 - Plans and specifications (P&S).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... is included in the construction. (b) 7 CFR 1755.93 provides a list of the RUS forms of... standards and specifications listed in 7 CFR part 1755 shall be included in the P&S. When RUS has not...) The insurance provision shall provide coverage as required by 7 CFR 1788. (ii) A contractor's...

  18. 7 CFR 1753.7 - Plans and specifications (P&S).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... is included in the construction. (b) 7 CFR 1755.93 provides a list of the RUS forms of... standards and specifications listed in 7 CFR part 1755 shall be included in the P&S. When RUS has not...) The insurance provision shall provide coverage as required by 7 CFR 1788. (ii) A contractor's...

  19. Adapting STePS, an Adult Team Problem Solving Model, for Use with Sixth Grade Students.

    ERIC Educational Resources Information Center

    Sheive, L. T.; And Others

    Structured Team Problem Solving (STePS) is a problem solving model for shared decision making. This project uses the model to discover if children can learn using this method, and what adaptations would be necessary for child use. Sixth grade students in their social studies class worked together in teams (6-8) to identify what they already think…

  20. High-resolution refractive index anisotropy measurement in optical fibers through phase retardation modulation

    NASA Astrophysics Data System (ADS)

    Sévigny, Benoit; Busque, François; Godbout, Nicolas; Lacroix, Suzanne; Faucher, Mathieu

    2008-03-01

    We present an improved, high-resolution method for the measurement of phase retardation induced by the material birefringence of optical fibers. Such a method can be used to retrieve information about the spatial distribution of refractive index anisotropy in the fiber by comparing the accumulated phase of a polarization component oriented along the fiber transmission axis and another located in the transverse plane. The method is based on the nonlinear regression of a phase modulated signal of known modulation amplitude altered by the sample. Experimental results obtained with our method for a standard telecommunications fiber (the Corning SMF-28) as well as photosensitive fibers (Fibercore PS1250 and PS1500) are presented with a noise-limited phase resolution below 10-4 radians and a spatial resolution below 1 μm. An analysis of the limitation of such measurement methods is also presented including diffraction by the fibers.

  1. Higher Tetanus Toxoid Immunity 2 Years After PsA-TT Introduction in Mali

    PubMed Central

    Basta, Nicole E.; Borrow, Ray; Berthe, Abdoulaye; Onwuchekwa, Uma; Dembélé, Awa Traoré Eps; Almond, Rachael; Frankland, Sarah; Patel, Sima; Wood, Daniel; Nascimento, Maria; Manigart, Olivier; Trotter, Caroline L.; Greenwood, Brian; Sow, Samba O.

    2015-01-01

    Background. In 2010, mass vaccination with a then-new meningococcal A polysaccharide–tetanus toxoid protein conjugate vaccine (PsA-TT, or MenAfriVac) was undertaken in 1- to 29-year-olds in Bamako, Mali. Whether vaccination with PsA-TT effectively boosts tetanus immunity in a population with heterogeneous baseline tetanus immunity is not known. We assessed the impact of PsA-TT on tetanus toxoid (TT) immunity by quantifying age- and sex-specific immunity prior to and 2 years after introduction. Methods. Using a household-based, age-stratified design, we randomly selected participants for a prevaccination serological survey in 2010 and a postvaccination survey in 2012. TT immunoglobulin G (IgG) antibodies were quantified and geometric mean concentrations (GMCs) pre- and postvaccination among all age groups targeted for vaccination were compared. The probability of TT IgG levels ≥0.1 IU/mL (indicating short-term protection) and ≥1.0 IU/mL (indicating long-term protection) by age and sex was determined using logistic regression models. Results. Analysis of 793 prevaccination and 800 postvaccination sera indicated that while GMCs were low pre–PsA-TT, significantly higher GMCs in all age–sex strata were observed 2 years after PsA-TT introduction. The percentage with short-term immunity increased from 57.1% to 88.4% (31.3-point increase; 95% confidence interval [CI], 26.6–36.0;, P < .0001) and with long-term immunity increased from 20.0% to 58.5% (38.5-point increase; 95% CI, 33.7–43.3; P < .0001) pre- and postvaccination. Conclusions. Significantly higher TT immunity was observed among vaccine-targeted age groups up to 2 years after Mali's PsA-TT mass vaccination campaign. Our results, combined with evidence from clinical trials, strongly suggest that conjugate vaccines containing TT such as PsA-TT should be considered bivalent vaccines because of their ability to boost tetanus immunity. PMID:26553691

  2. EGb761 improves cognitive function and regulates inflammatory responses in the APP/PS1 mouse.

    PubMed

    Wan, Wenbin; Zhang, Chunyan; Danielsen, Mark; Li, Qianlei; Chen, Wenjing; Chan, Yuanjin; Li, Yaming

    2016-08-01

    There is accumulating evidence that the Ginkgo biloba extract EGb761 may help to prevent Alzheimer's disease (AD). However, the underlying mechanism of its action remains to be elaborated. In this study, we examined the effects of EGb761 using the APP/PS1 transgenic mouse model of AD. Two-month-old APP/PS1 mice were supplemented with EGb761 daily for 6months. We found that this chronic treatment with EGb761 improved the cognitive function of these mice and also significantly alleviated amyloid plaque deposition. Although the level of insoluble amyloid beta (Aβ) was decreased, the soluble content of Aβ was not changed after administration of EGb761. We then determined the changes in central inflammation and observed that the activated microglia around amyloid plaque was increased in these treated mice. We also found that chronic EGb761 treatment downregulated pro-inflammatory cytokines and inducible nitric oxide synthase (iNOS), and upregulated anti-inflammatory cytokines and Arginase-1 (Arg-1), suggesting that EGb761 regulated the phenotype of activated microglia in the APP/PS1 mouse brain. In support of this, pretreatment of the BV2 microglial cell line with EGb761 inhibited the inflammatory reaction to Aβ. Furthermore, the addition of conditioned media derived from BV2 cells that were co-treated with Aβ and EGb761, protected neurons against treatment of Aβ and inhibited apoptotic damage. Taken together, our results demonstrated that EGb761 provided a protective effect in APP/PS1 mouse. This protection was correlated with an inhibition of the pro-inflammatory effects of microglia and an induction of anti-inflammatory effects. These results strongly suggest that EGb761 provides a protective effect in APP/PS1 mouse via regulation of inflammation in the brain. PMID:27220811

  3. Near-IR and PS-OCT imaging of developmental defects in dental enamel

    NASA Astrophysics Data System (ADS)

    Hirasuna, Krista; Fried, Daniel; Darling, Cynthia L.

    2007-02-01

    Polarization sensitive optical coherence tomography (PS-OCT) and near-IR (NIR) imaging are promising new technologies under development for monitoring early carious lesions. Fluorosis is a growing problem in the U.S., and the more prevalent mild fluorosis can be visually mistaken for early enamel demineralization. Some initial NIR images suggest that enamel defects and dental caries manifest different optical behavior in the NIR. Unfortunately, there is little quantitative information available regarding the differences in optical properties of sound enamel, enamel developmental defects, and demineralized enamel due to caries. This study tested the hypothesis that hypomineralized enamel due to fluorosis can be differentiated from demineralized enamel due to caries using NIR and PS-OCT imaging because of different optical behavior in the NIR. Thirty extracted human teeth with various degrees of suspected fluorosis and/or caries were imaged using PS-OCT and NIR transillumination. An InGaAs camera and a near-IR diode laser were used to measure the optical attenuation through transverse tooth sections (~200 μm). Developmental defects were clearly visible in the polarization-resolved OCT images, demonstrating that PS-OCT can be used to nondestructively measure the depth and possible severity of the defects. Enamel defects on whole teeth that could be imaged with high contrast with visible light were transparent in the near-IR while demineralized areas due to caries were opaque. In contrast, dental caries could be clearly distinguished from sound enamel. This study suggests that PS-OCT and NIR methods may potentially be used as tools to assess the severity and extent of enamel defects and for the differentiation of mild fluorosis defects from early carious lesions.

  4. Basidiomycete DyPs: Genomic diversity, structural-functional aspects, reaction mechanism and environmental significance.

    PubMed

    Linde, Dolores; Ruiz-Dueñas, Francisco J; Fernández-Fueyo, Elena; Guallar, Victor; Hammel, Kenneth E; Pogni, Rebecca; Martínez, Angel T

    2015-05-15

    The first enzyme with dye-decolorizing peroxidase (DyP) activity was described in 1999 from an arthroconidial culture of the fungus Bjerkandera adusta. However, the first DyP sequence had been deposited three years before, as a peroxidase gene from a culture of an unidentified fungus of the family Polyporaceae (probably Irpex lacteus). Since the first description, fewer than ten basidiomycete DyPs have been purified and characterized, but a large number of sequences are available from genomes. DyPs share a general fold and heme location with chlorite dismutases and other DyP-type related proteins (such as Escherichia coli EfeB), forming the CDE superfamily. Taking into account the lack of an evolutionary relationship with the catalase-peroxidase superfamily, the observed heme pocket similarities must be considered as a convergent type of evolution to provide similar reactivity to the enzyme cofactor. Studies on the Auricularia auricula-judae DyP showed that high-turnover oxidation of anthraquinone type and other DyP substrates occurs via long-range electron transfer from an exposed tryptophan (Trp377, conserved in most basidiomycete DyPs), whose catalytic radical was identified in the H2O2-activated enzyme. The existence of accessory oxidation sites in DyP is suggested by the residual activity observed after site-directed mutagenesis of the above tryptophan. DyP degradation of substituted anthraquinone dyes (such as Reactive Blue 5) most probably proceeds via typical one-electron peroxidase oxidations and product breakdown without a DyP-catalyzed hydrolase reaction. Although various DyPs are able to break down phenolic lignin model dimers, and basidiomycete DyPs also present marginal activity on nonphenolic dimers, a significant contribution to lignin degradation is unlikely because of the low activity on high redox-potential substrates. PMID:25637654

  5. IMPEDANCE CONSIDERATIONS FOR THE DESIGN OF THE VACUUM SYSTEM OF THE CERN PS2

    SciTech Connect

    Bane, K.L.F.; Stupakov, G.; Wienands, U.; Benedikt, M.; Grudiev, A.; Mahner, E.; /SLAC /CERN

    2010-08-26

    In order for the LHC to reach an ultimate luminosity goal of 10{sup 35}/cm{sup 2}/s, CERN is considering upgrade options for the LHC injector chain, including a new 50 GeV synchrotron of about 1.3 km length for protons and heavy ions, to be called the PS2 [1]. The proton energy will be ramped from 4 GeV to 50 GeV in 1.2 s, and the design proton current for LHC operation is 2.7 A. In the LARP framework, we are studying the instability thresholds and the impedance requirements of the vacuum system for the PS2. Goal of this study is to develop an impedance budget for the machine. We consider the standard single and multi-bunch collective effects that may be an issue in the PS2. For single bunch, we study the microwave instability and the transverse mode coupling instability (TMCI); for multi-bunch, the transverse coupled bunch instability. While the impedance budget will include many components in the machine, at present, we only have sufficient information to include the resistance of the beam pipe, the vacuum flanges that connect the various pieces of the vacuum chamber, and space charge impedance in our estimate. Note that earlier estimates of the impedance and its effects in the PS2 can be found in Ref. [2]. Table 1 presents selected PS2 parameters that will be used in the calculations. The equations used, unless indicated otherwise, can be found in Ref. [3].

  6. Induced pluripotent stem (iPS) cells offer a powerful new tool for the life sciences.

    PubMed

    Nakamura, Y

    2010-01-01

    Stem cell biology started with the analysis of somatic stem cells that function to maintain the adult body. We now know that the body is maintained by regeneration of a wide range of cell types, such as skin cells, blood cells and gastrointestinal mucous cells, from somatic stem cells. This regenerative activity is essential for survival. Regenerative medicine was initiated to identify therapies that support and/or accelerate this natural regenerative ability. For example, bone marrow transplantation is a therapy for reconstituting hematopoiesis from the hematopoietic stem cells present in the donor bone marrow. The successful development of a protocol for obtaining human embryonic stem (ES) cells prompted medical scientists to utilize human ES cells for regenerative medicine. However, use of these cells raises ethical issues as they are derived from human embryos. An alternative approach using ES-like pluripotent stem cells has the considerable advantage that it does not necessitate use of human embryos. Pluripotent stem cells can be induced from terminally differentiated somatic cells by the introduction of only four defined factors. The products of this method are termed "induced pluripotent stem (iPS)" cells. iPS cells have considerable promise as a substitute for ES cells not only for regenerative medicine but also in many other fields. For example, liver and heart cells derived from iPS cells can be used in pharmaceutical research. In addition, iPS cell technology opens new avenues of disease research, for example, by construction of so-called "disease-specific iPS cells" from a patient's somatic cells. PMID:24693054

  7. High-resolution transversal load sensor using a random distributed feedback fiber laser

    NASA Astrophysics Data System (ADS)

    DeMiguel-Soto, V.; Leandro, D.; Lopez-Amo, M.

    2016-05-01

    In this work, a new application of random distributed feedback lasers to fiber optic sensing has been presented. The particular properties of these lasers, such as the lack of longitudinal modes and high stability, have been exploited to monitor transversal load using a phase-shifted fiber Bragg grating (PS-FBG), obtaining a resolution of 1g and a sensitivity of 3.95GHz/Kg. Due to the PS-FBG birefringence and the load-interrelated transmission lines generated by the PS-FBG along the orthogonal polarization directions, the beating of the two emission lines generated in the laser can be monitored in the electrical domain. As a result, transversal load applied on the sensor can be measured.

  8. Conflict Resolution Communications.

    ERIC Educational Resources Information Center

    Lincoln, Melinda G.

    2002-01-01

    Suggests that, due to escalating violence in contemporary society, community colleges should offer certificate or degree programs in conflict resolution. Describes a conflict resolution communication program, which teaches communication skills, mediation processes, and coping strategies to prospective mediators. (NB)

  9. Age-Related Loss of Synaptophysin Immunoreactive Presynaptic Boutons within the Hippocampus of APP751SL, PS1M146L, and APP751SL/PS1M146L Transgenic Mice

    PubMed Central

    Rutten, Bart P.F.; Van der Kolk, Nicolien M.; Schafer, Stephanie; van Zandvoort, Marc A.M.J.; Bayer, Thomas A.; Steinbusch, Harry W.M.; Schmitz, Christoph

    2005-01-01

    Neuron and synapse loss are important features of the neuropathology of Alzheimer’s disease (AD). Recently, we observed substantial age-related hippocampal neuron loss in APP751SL/PS1M146L transgenic mice but not in PS1M146L mice. Here, we investigated APP751SL mice, PS1M146L mice, and APP751SL/PS1M146L mice for age-related alterations in synaptic integrity within hippocampal stratum moleculare of the dentate gyrus (SM), stratum lucidum of area CA3 (SL), and stratum radiatum of area CA1–2 (SR) by analyzing densities and numbers of synaptophysin-immunoreactive presynaptic boutons (SIPBs). Wild-type mice, APP751SL mice and PS1M146L mice showed similar amounts of age-related SIPB loss within SM, and no SIPB loss within SL. Both APP751SL mice and PS1M146L mice showed age-related SIPB loss within SR. Importantly, APP751SL/PS1M146L mice displayed the severest age-related SIPB loss within SM, SL, and SR, even in regions free of extracellular Aβ deposits. Together, these mouse models offer a unique framework to study the impact of several molecular and cellular events caused by mutant APP and/or mutant PS1 on age-related alterations in synaptic integrity. The observation of age-related SIPB loss within SR of PS1M146L mice supports a role of mutant PS1 in neurodegeneration apart from its contribution to alterations in Aβ generation. PMID:15972962

  10. MYC cis-Elements in PsMPT Promoter Is Involved in Chilling Response of Paeonia suffruticosa

    PubMed Central

    Liu, Shaoqing; Dong, Lei; Liu, Chunying; Song, Wenwen; Liu, Jingjing; Gai, Shupeng

    2016-01-01

    The MPT transports Pi to synthesize ATP. PsMPT, a chilling-induced gene, was previously reported to promote energy metabolism during bud dormancy release in tree peony. In this study, the regulatory elements of PsMPT promoter involved in chilling response were further analyzed. The PsMPT transcript was detected in different tree peony tissues and was highly expressed in the flower organs, including petal, stigma and stamen. An 1174 bp of the PsMPT promoter was isolated by TAIL-PCR, and the PsMPT promoter::GUS transgenic Arabidopsis was generated and analyzed. GUS staining and qPCR showed that the promoter was active in mainly the flower stigma and stamen. Moreover, it was found that the promoter activity was enhanced by chilling, NaCl, GA, ACC and NAA, but inhibited by ABA, mannitol and PEG. In transgenic plants harboring 421 bp of the PsMPT promoter, the GUS gene expression and the activity were significantly increased by chilling treatment. When the fragment from -421 to -408 containing a MYC cis-element was deleted, the chilling response could not be observed. Further mutation analysis confirmed that the MYC element was one of the key motifs responding to chilling in the PsMPT promoter. The present study provides useful information for further investigation of the regulatory mechanism of PsMPT during the endo-dormancy release. PMID:27228117

  11. 75 FR 16748 - Final Voluntary Product Standard; DOC PS 20-10 “American Softwood Lumber Standard”

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-02

    ...The National Institute of Standards and Technology (NIST) announces voluntary product standard DOC PS 20-10 ``American Softwood Lumber Standard'' which will supersede DOC PS 20-05. The Standard establishes standard sizes and requirements for developing and coordinating the lumber grades of the various species of softwood lumber, the assignment of design values, and the preparation of grading......

  12. MYC cis-Elements in PsMPT Promoter Is Involved in Chilling Response of Paeonia suffruticosa.

    PubMed

    Zhang, Yuxi; Sun, Tingzhao; Liu, Shaoqing; Dong, Lei; Liu, Chunying; Song, Wenwen; Liu, Jingjing; Gai, Shupeng

    2016-01-01

    The MPT transports Pi to synthesize ATP. PsMPT, a chilling-induced gene, was previously reported to promote energy metabolism during bud dormancy release in tree peony. In this study, the regulatory elements of PsMPT promoter involved in chilling response were further analyzed. The PsMPT transcript was detected in different tree peony tissues and was highly expressed in the flower organs, including petal, stigma and stamen. An 1174 bp of the PsMPT promoter was isolated by TAIL-PCR, and the PsMPT promoter::GUS transgenic Arabidopsis was generated and analyzed. GUS staining and qPCR showed that the promoter was active in mainly the flower stigma and stamen. Moreover, it was found that the promoter activity was enhanced by chilling, NaCl, GA, ACC and NAA, but inhibited by ABA, mannitol and PEG. In transgenic plants harboring 421 bp of the PsMPT promoter, the GUS gene expression and the activity were significantly increased by chilling treatment. When the fragment from -421 to -408 containing a MYC cis-element was deleted, the chilling response could not be observed. Further mutation analysis confirmed that the MYC element was one of the key motifs responding to chilling in the PsMPT promoter. The present study provides useful information for further investigation of the regulatory mechanism of PsMPT during the endo-dormancy release. PMID:27228117

  13. Nearly penalty-free, less than 4 ps supercontinuum Gbit/s pulse generation over 1535-1560 nm

    NASA Astrophysics Data System (ADS)

    Morioka, T.; Kawanishi, S.; Mori, K.; Saruwatari, M.

    1994-05-01

    Nearly penalty-free less than 4ps supercontinuum WDM pulses are generated at 6.3 Gbit/s over 1535-1560 nm for the first time using a 200 nm superbroadened supercontinuum in an optical fibre pumped by 1.7 W, 3.3 ps, 1542 nm short pulses from an Er(3+)-doped fibre ring laser.

  14. Investigation of Blend Miscibility of a Ternary PS/PCHMA/PMMA System Using SIMS and Mean-Field Theory

    SciTech Connect

    Harton,S.; Koga, T.; Stevie, F.; Araki, T.; Ade, H.

    2005-01-01

    Poly(cyclohexyl methacrylate) (PCHMA) and polystyrene (PS) are miscible with each other, but each is highly immiscible with PMMA. Identifiable by the asymmetries in the binary mean-field interaction parameters {chi}, PS preferentially segregates to the PCHMA/PMMA interface. Secondary ion mass spectrometry was used to provide real-space depth profiles of deuterated PS (dPS) in a miscible blend with PCHMA. The initial dPS concentration was varied from 5 to 20% (v/v), and the blend film was annealed at 150 C on a film of PMMA for 42 h. X-ray reflectometry was used to determine the interfacial width between PCHMA and PMMA at 150 C. Using self-consistent mean-field theory, good agreement was found between the experimental and theoretical interfacial excess Z* of dPS at each concentration. Because of their similar glass transition temperatures ({approx}100 C for PS and PCHMA) and the ability of PS and PCHMA to be controllably synthesized with low polydispersities, we anticipate this blend to be a model system for future investigations of such phenomena as diffusion in miscible blends and diffusion near surfaces and interfaces.

  15. Alteration of behavior and monoamine levels attributable to Lactobacillus plantarum PS128 in germ-free mice.

    PubMed

    Liu, Wei-Hsien; Chuang, Hsiao-Li; Huang, Yen-Te; Wu, Chien-Chen; Chou, Geng-Ting; Wang, Sabrina; Tsai, Ying-Chieh

    2016-02-01

    Probiotics, defined as live bacteria or bacterial products, confer a significant health benefit to the host, including amelioration of anxiety-like behavior and psychiatric illnesses. Here we administered Lactobacillus plantarum PS128 (PS128) to a germ-free (GF) mouse model to investigate the impact of the gut-brain axis on emotional behaviors. First, we demonstrated that chronic administration of live PS128 showed no adverse effects on physical health. Then, we found that administration of live PS128 significantly increased the total distance traveled in the open field test and decreased the time spent in the closed arm in the elevated plus maze test, whereas the administration of PS128 had no significant effects in the depression-like behaviors of GF mice. Also, chronic live PS128 ingestion significantly increased the levels of both serotonin and dopamine in the striatum, but not in the prefrontal cortex or hippocampus. These results suggest that the chronic administration of PS128 is safe and could induce changes in emotional behaviors. The behavioral changes are correlated with the increase in the monoamine neurotransmitters in the striatum. These findings suggest that daily intake of the L. plantarum strain PS128 could improve anxiety-like behaviors and may be helpful in ameliorating neuropsychiatric disorders. PMID:26522841

  16. SALT spectroscopic classification of PS16atu (SN 2016atv) as a type-Ia supernova after maximum light

    NASA Astrophysics Data System (ADS)

    Jha, S. W.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Kotze, M.

    2016-03-01

    We obtained SALT (+RSS) spectroscopy of PS16atu (SN 2016atv) on 2016 Mar 10.1 UT, covering the wavelength range 350-920 nm. Cross-correlation of the spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows PS16atu is a type-Ia supernova approximately a week past maximum light.

  17. Electrical properties comparison of TiO2/PS/Si devices fabricated by spin coating and electron beam gun

    NASA Astrophysics Data System (ADS)

    Dariani, R. S.; Faraji, F.

    2016-04-01

    Three porous silicon (PS) samples with different porosities by electrochemical anodization are fabricated. Then, TiO2 nanoparticles are deposited on PS by two methods, spin coating and electron beam gun. I- V characteristics of all samples show diode behavior. Our result showed that transient current decreases with increasing porosity for PS/Si samples while increases for TiO2/PS/Si samples in both deposition methods. The reason could be due to filling pores by TiO2 nanoparticles and reduction of resistivity on PS surface. Also, our result showed that transient current increases highly for samples which were deposited by electron beam gun with respect to spin coating. The reason could be that in spin coating method TiO2 sol with high viscosity was used and causes that TiO2 nanoparticles cannot easily penetrate into PS pores. But in electron beam gun method TiO2 nanoparticles reaches to PS surface as a few atoms and can easily penetrate into PS pores. Ideality factor of our samples reduces after TiO2 deposition. Also, ideality factor of samples which were deposited by electron beam gun decreases with respect to spin coating, since transient current and I- V curve slop increase in electron beam gun.

  18. Using the 5Ps Leadership Analysis to Examine the Battle of Antietam: An Explanation and Case Study

    ERIC Educational Resources Information Center

    Hull, Bradley Z.; Allen, Scott J.

    2012-01-01

    The authors describe an exploratory analytical tool called "The 5Ps Leadership Analysis" (Personal Attributes, Position, Purpose, Practices/Processes, and Product) as a heuristic for better understanding the complexities of leadership. Using "The 5Ps Leadership Analysis," the authors explore the leadership of General Robert E. Lee of the…

  19. Preliminary evaluation of PS300: A new self-lubricating high temperature composite coating for use to 800{degrees}C

    SciTech Connect

    DellaCorte, C.; Edmonds, B.J.

    1996-12-31

    This paper introduces PS300, a plasma sprayed, self-lubricating composite coating for use in sliding contacts at temperatures to 800{degrees}C. PS300 is a metal bonded chrome oxide coating with silver and BaF{sub 2}/CaF{sub 2} eutectic solid lubricant additives. PS300 is similar to PS200, a chromium carbide based coating; which is currently being investigated for a variety of tribological applications. In pin-on-disk testing up to 650{degrees}C, PS300 exhibited comparable friction and wear properties to PS200. The PS300 matrix, which is predominantly chromium oxide rather than chromium carbide, does not require diamond grinding and polishes readily with silicon carbide abrasives greatly reducing manufacturing costs compared to PS200. It is anticipated that PS300 has potential for sliding bearing and seal applications in both aerospace and general industry.

  20. The Current Status of iPS Cells in Cardiac Research and Their Potential for Tissue Engineering and Regenerative Medicine

    PubMed Central

    Martins, Ana M.; Vunjak-Novakovic, Gordana

    2015-01-01

    The recent availability of human cardiomyocytes derived from induced pluripotent stem (iPS) cells opens new opportunities to build in vitro models of cardiac disease, screening for new drugs, and patient-specific cardiac therapy. Notably, the use of iPS cells enables studies in the wide pool of genotypes and phenotypes. We describe progress in reprogramming of induced pluripotent stem (iPS) cells towards the cardiac lineage/differentiation. The focus is on challenges of cardiac disease modeling using iPS cells and their potential to produce safe, effective and affordable therapies/applications with the emphasis of cardiac tissue engineering. We also discuss implications of human iPS cells to biological research and some of the future needs. PMID:24425421

  1. Resolution limitations and optimization of the LLNL streak camera focus

    SciTech Connect

    Lerche, R.A.; Griffith, R.L.

    1987-09-01

    The RCA C73435 image tube is biased at voltages far from its original design in the LLNL ultrafast (10 ps) streak camera. Its output resolution at streak camera operating potentials has been measured as a function of input slit width, incident-light wavelength, and focus-grid voltage. The temporal resolution is insensitive to focus-grid voltage for a narrow (100 ..mu..m) input slit, but is very sensitive to focus-grid voltage for a wide (2 mm) input slit. At the optimum wide-slit focus voltage, temporal resolution is insensitive to slit width. Spatial resolution is nearly independent of focus-grid voltage for values that give good temporal resolution. Both temporal and spatial resolution depend on the incident-light wavelength. Data for 1.06-..mu..m light show significantly better focusing than for 0.53-..mu..m light. Streak camera operation is simulated with a computer program that calculates photoelectron trajectories. Electron ray tracing describes all of the observed effects of slit width, incident-light wavelength, and focus-grid voltage on output resolution. 7 refs.

  2. Ataxia-telangiectasia mutated (ATM) deficiency decreases reprogramming efficiency and leads to genomic instability in iPS cells

    SciTech Connect

    Kinoshita, Taisuke; Nagamatsu, Go; Kosaka, Takeo; Takubo, Keiyo; Hotta, Akitsu; Ellis, James; Suda, Toshio

    2011-04-08

    Highlights: {yields} iPS cells were induced with a fluorescence monitoring system. {yields} ATM-deficient tail-tip fibroblasts exhibited quite a low reprogramming efficiency. {yields} iPS cells obtained from ATM-deficient cells had pluripotent cell characteristics. {yields} ATM-deficient iPS cells had abnormal chromosomes, which were accumulated in culture. -- Abstract: During cell division, one of the major features of somatic cell reprogramming by defined factors, cells are potentially exposed to DNA damage. Inactivation of the tumor suppressor gene p53 raised reprogramming efficiency but resulted in an increased number of abnormal chromosomes in established iPS cells. Ataxia-telangiectasia mutated (ATM), which is critical in the cellular response to DNA double-strand breaks, may also play an important role during reprogramming. To clarify the function of ATM in somatic cell reprogramming, we investigated reprogramming in ATM-deficient (ATM-KO) tail-tip fibroblasts (TTFs). Although reprogramming efficiency was greatly reduced in ATM-KO TTFs, ATM-KO iPS cells were successfully generated and showed the same proliferation activity as WT iPS cells. ATM-KO iPS cells had a gene expression profile similar to ES cells and WT iPS cells, and had the capacity to differentiate into all three germ layers. On the other hand, ATM-KO iPS cells accumulated abnormal genome structures upon continuous passages. Even with the abnormal karyotype, ATM-KO iPS cells retained pluripotent cell characteristics for at least 20 passages. These data indicate that ATM does participate in the reprogramming process, although its role is not essential.

  3. A high resolution Timing Counter for the MEG II experiment

    NASA Astrophysics Data System (ADS)

    De Gerone, M.; Bevilacqua, A.; Biasotti, M.; Boca, G.; Cattaneo, P. W.; Gatti, F.; Nishimura, M.; Ootani, W.; Pizzigoni, G.; Rossella, M.; Shibata, N.; Siccardi, F.; Simonetta, M.; Uchiyama, Y.; Yoshida, K.

    2016-07-01

    The development of a Timing Counter detector designed for the MEGII upgrade of the MEG experiment, which strives to improve the sensitivity on the μ+ →e+ γ decay of an order of magnitude, is presented. It is based on two sets of counters (sectors) arranged on a semi-cylindrical structure; each sector consists of 256 counters. Each counter consists of tile of fast scintillator with a dual-side read-out based on SiPM arrays in series connection. The high granularity has two advantages: optimized size for achieving high resolution (75 ps) for the single counter, and a signal e+ crosses several counters, so that resolution improves by averaging multiple time measurements. A prototype has been built and tested both in BTF and PSI facilities in order to prove the multi-hit scheme in MEG-like beam conditions. A 35 ps resolution with eight hits has been obtained with a e+ beam at 100 kHz. The first sector will be tested in the MEG II pre-engineering run planned at the end of 2015.

  4. Radio frequency phototube and optical clock: High resolution, high rate and highly stable single photon timing technique

    SciTech Connect

    Margaryan, Amur

    2011-10-01

    A new timing technique for single photons based on the radio frequency phototube and optical clock or femtosecond optical frequency comb generator is proposed. The technique has a 20 ps resolution for single photons, is capable of operating with MHz frequencies and achieving 10 fs instability level.

  5. Synthesis and Melt Self-Assembly of PS-PMMA-PLA Triblock Bottlebrush Copolymers

    SciTech Connect

    Bolton, Justin; Rzayev, Javid

    2014-07-03

    Polystyrene–poly(methyl methacrylate)–polylactide (PS–PMMA–PLA) triblock bottlebrush copolymer with nearly symmetric volume fractions was synthesized by grafting from a symmetrical triblock backbone and the resulting melt was characterized by scanning electron microscopy and small-angle X-ray scattering. The copolymer backbone was prepared by sequential reversible addition–fragmentation chain transfer (RAFT) polymerization of solketal methacrylate (SM), 2-(bromoisobutyryl)ethyl methacrylate (BIEM), and 5-(trimethylsilyl)-4-pentyn-1-ol methacrylate (TPYM). PMMA branches were grafted by atom transfer radical polymerization from the poly(BIEM) segment, PS branches were grafted by RAFT polymerization from the poly(TPYM) block after installment of the RAFT agents, while PLA side chains were grafted from the deprotected poly(SM) block. The resulting copolymer was found to exhibit a lamellae morphology with a domain spacing of 79 nm. Differential scanning calorimetry analysis indicated that PMMA was preferentially mixing with PS while phase separating from PLA domains.

  6. The effect of high-index liquids on PS-OCT imaging of dental caries

    NASA Astrophysics Data System (ADS)

    Jones, Robert S.; Fried, Daniel

    2005-03-01

    The aim of this study was to investigate the effects of high refractive index liquids on PS-OCT imaging of dental enamel. Several biocompatible agents such as propylene glycol and glycerol that have been proposed or utilized for soft tissue OCT experiments (skin and GI mucosa) were applied to the occlusal surfaces of sound and carious teeth. This study determined that the application of high refractive index liquids increased penetration depth in sound enamel to a greater degree than dried or water moistened samples. The results also demonstrated that image contrast between sound and carious enamel is dependent on the viscosity of the liquid and the degree of porosity of the carious lesion. The use of liquid agents with different viscositites in PS-OCT imaging may help determine the severity and depth of caries lesions in the occlusal pits and fissures.

  7. Titin Mutations in iPS cells Define Sarcomere Insufficiency as a Cause of Dilated Cardiomyopathy

    PubMed Central

    Hinson, John T.; Chopra, Anant; Nafissi, Navid; Polacheck, William J.; Benson, Craig C.; Swist, Sandra; Gorham, Joshua; Yang, Luhan; Schafer, Sebastian; Sheng, Calvin C.; Haghighi, Alireza; Homsy, Jason; Hubner, Norbert; Church, George; Cook, Stuart A.; Linke, Wolfgang A.; Chen, Christopher S.; Seidman, J. G.; Seidman, Christine E.

    2015-01-01

    Human mutations that truncate the massive sarcomere protein titin (TTNtv) are the most common genetic cause for dilated cardiomyopathy (DCM), a major cause of heart failure and premature death. Here we show that cardiac microtissues engineered from human induced pluripotent stem (iPS) cells are a powerful system for evaluating the pathogenicity of titin gene variants. We found that certain missense mutations, like TTNtv, diminish contractile performance and are pathogenic. By combining functional analyses with RNAseq, we explain why truncations in the A-band domain of TTN cause DCM while truncations in the I-band are better tolerated. Finally, we demonstrate that mutant titin protein in iPS-cardiomyocytes results in sarcomere insufficiency, impaired responses to mechanical and β-adrenergic stress, and attenuated growth factor and cell signaling activation. Our findings indicate that titin mutations cause DCM by disrupting critical linkages between sarcomerogenesis and adaptive remodelling. PMID:26315439

  8. Rheological/Morphological Study of PS/CNT Nanocomposite Electrospun Fibers

    NASA Astrophysics Data System (ADS)

    Mazinani, Saeedeh; Ajji, Abdellah; Dubois, Charles

    2008-07-01

    This work depicts rheological characteristics of Polystyrene (PS)/Carbon Nanotube (CNT) nanocomposite solutions and their incidence on the morphological properties of final electrospun fibers. Nanocomposite fibers were obtained through electrospinning of PS/Di-Methyl Formamide (DMF) solutions containing different concentrations and types of Carbon Nanotubes. The morphology of fibers at different concentrations and types of CNTs was studied using Scanning Electron Microscopy (SEM) and Optical Microscopy. Correlation between initial CNT dispersion and final fibers morphologies was obtained using viscometry results and optical microscopy of initial solutions. The results obtained show that beads presence in fibers are due to nanoparticles agglomerations. A styrenic copolymer (Styrene-Butadiene-Styrene, SBS-Kraton) was employed as a compatibilizing agent to improve CNTs dispersion instead of chemical modification. Addition of copolymer affects both final fiber morphologies and CNT dispersion condition.

  9. Electron-cloud Build-up Simulations in the Proposed PS2: Status Report

    SciTech Connect

    Furman, M. A.; De Maria, R.; Papaphilippou, Y.; Rumolo, G.

    2010-05-05

    A replacement for the PS storage ring is being considered, in the context of the future LHC accelerator complex upgrade, that would likely place the new machine (the PS2) in a regime where the electron-cloud (EC) effect might be significant. We report here our current estimate of the EC density ne in the bending magnets and the field-free regions at injection and extraction beam energy, for both proposed bunch spacings, tb = 25 and 50 ns. The primary model parameters exercised are the peak secondary emission yield (SEY) delta max, the electron-wall impact energy at which the SEY peaks, Emax, and the chamber radius a in the fieldfree regions. We present many of our results as a function of the bunch intensity Nb, and we provide a tentative explanation for the non-monotonic behavior of ne as a function of Nb.

  10. Commercialization of NASA PS304 Solid Lubricant Coating Enhanced by Fundamental Powder Flow Research

    NASA Technical Reports Server (NTRS)

    Stanford, Malcolm K.

    2003-01-01

    The NASA Glenn Research Center has developed a patented high-temperature solid lubricant coating, designated PS304, for reducing friction and wear in bearing systems. The material used to produce the coating is initially a blend of metallic and ceramic powders that are deposited on the bearing surface by the plasma spray process. PS304 was developed to lubricate foil air bearings in Oil-Free turbomachinery, where the moving surfaces are coated with a hydrodynamic air film except at the beginning and end of an operation cycle when the air film is not present. The coating has been successful in several applications including turbochargers, land-based turbines, and industrial drying furnace conveyor components, with current development activities directed at implementation in Oil-Free aeropropulsion engines.

  11. Effects of Humidity On the Flow Characteristics of PS304 Plasma Spray Feedstock Powder Blend

    NASA Technical Reports Server (NTRS)

    Stanford, Malcolm K.; DellaCorte, Christopher

    2002-01-01

    The effects of environmental humidity on the flow characteristics of PS304 feedstock have been investigated. Angular and spherical BaF2-CaF2 powder was fabricated by comminution and by atomization, respectively. The fluorides were added incrementally to the nichrome, chromia, and silver powders to produce PS304 feedstock. The powders were dried in a vacuum oven and cooled to a Tom temperature under dry nitrogen. The flow of the powder was studied from 2 to 100 percent relative humidity (RH) The results suggest that the feedstock flow is slightly degraded with increasing humidity below 66 percent RH and is more affected above 66 percent RH. There was no flow above 88 percent RH. Narrower particle size distributions of the angular fluorides allowed flow up to 95 percent RH. These results offer guidance that enhances the commercial potential for this material system.

  12. XUV spectral analysis of ns- and ps-laser produced platinum plasmas

    NASA Astrophysics Data System (ADS)

    Wu, Tao; Higashiguchi, Takeshi; Li, Bowen; Suzuki, Yuhei; Arai, Goki; Dinh, Thanh-Hung; Dunne, Padraig; O'Reilly, Fergal; Sokell, Emma; O'Sullivan, Gerry

    2015-12-01

    XUV spectra of ns- and ps-laser produced platinum (Pt) plasmas in the 1-7 nm wavelength region, where Δn = 1 n = 4-5 and Δn = 0 n = 4-4 transitions dominate the observed emission, were investigated experimentally and theoretically. Ab initio calculations using the Hartree-Fock with configuration interaction (HFCI) Cowan suite of codes and the unresolved transition array (UTA) formalism, as well as consideration of previous predictions of isoelectronic trends, together with spectra obtained under different laser power densities are all employed to identify lines and a number of new features in spectra from Pt XX to Pt XLII. The possible reasons for the main differences between the ns- and ps-laser plasmas spectra are also demonstrated. This work extends previous analyses of the XUV spectra of laser produced gold, tungsten, tantalum, hafnium and rhenium plasmas in the 1-7 nm wavelength range.

  13. Generalized linear joint PP-PS inversion based on two constraints

    NASA Astrophysics Data System (ADS)

    Fang, Yuan; Zhang, Feng-Qi; Wang, Yan-Chun

    2016-03-01

    Conventional joint PP—PS inversion is based on approximations of the Zoeppritz equations and assumes constant VP/VS; therefore, the inversion precision and stability cannot satisfy current exploration requirements. We propose a joint PP—PS inversion method based on the exact Zoeppritz equations that combines Bayesian statistics and generalized linear inversion. A forward model based on the exact Zoeppritz equations is built to minimize the error of the approximations in the large-angle data, the prior distribution of the model parameters is added as a regularization item to decrease the ill-posed nature of the inversion, low-frequency constraints are introduced to stabilize the low-frequency data and improve robustness, and a fast algorithm is used to solve the objective function while minimizing the computational load. The proposed method has superior antinoising properties and well reproduces real data.

  14. Biological studies and electrical conductivity of paper sheet based on PANI/PS/Ag-NPs nanocomposite.

    PubMed

    Youssef, A M; Mohamed, S A; Abdel-Aziz, M S; Abdel-Aziz, M E; Turky, G; Kamel, S

    2016-08-20

    Polyaniline (PANI) with/without polystyrene (PS), was successfully manufactured in the occurrence of dispersed pulp fibers via the oxidative polymerization reaction of aniline monomer to produce conductive paper sheets containing PANI, PANI/PS composites. Additionally, sliver nitrate (Ag-NO3) was added by varied loadings to the oxidative polymerization of aniline monomer to provide sliver nanoparticles (Ag-NPs) emptied into the prepared paper sheets. The prepared paper sheets were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD) and infrared spectroscopy (IR), the mechanical properties of the prepared paper sheets were evaluated. Moreover, the electrical conductivity and biological studies such as cellulases assay, Microorganism & culture condition and detection of the released of Ag-NPs were evaluated. Furthermore, the prepared paper sheets were displayed good antibacterial properties contrary to gram positive and gram negative bacteria. Consequently, the prepared paper sheet may be used as novel materials for packaging applications. PMID:27178939

  15. Ultra-high resolution, polarization sensitive transversal optical coherence tomography for structural analysis and strain mapping

    NASA Astrophysics Data System (ADS)

    Wiesauer, Karin; Pircher, Michael; Goetzinger, Erich; Hitzenberger, Christoph K.; Engelke, Rainer; Ahrens, Gisela; Pfeiffer, Karl; Ostrzinski, Ute; Gruetzner, Gabi; Oster, Reinhold; Stifter, David

    2006-02-01

    Optical coherence tomography (OCT) is a contactless and non-invasive technique nearly exclusively applied for bio-medical imaging of tissues. Besides the internal structure, additionally strains within the sample can be mapped when OCT is performed in a polarization sensitive (PS) way. In this work, we demonstrate the benefits of PS-OCT imaging for non-biological applications. We have developed the OCT technique beyond the state-of-the-art: based on transversal ultra-high resolution (UHR-)OCT, where an axial resolution below 2 μm within materials is obtained using a femtosecond laser as light source, we have modified the setup for polarization sensitive measurements (transversal UHR-PS-OCT). We perform structural analysis and strain mapping for different types of samples: for a highly strained elastomer specimen we demonstrate the necessity of UHR-imaging. Furthermore, we investigate epoxy waveguide structures, photoresist moulds for the fabrication of micro-electromechanical parts (MEMS), and the glass-fibre composite outer shell of helicopter rotor blades where cracks are present. For these examples, transversal scanning UHR-PS-OCT is shown to provide important information about the structural properties and the strain distribution within the samples.

  16. Quantitative Proteomic Analysis of Mitochondria in Aging PS-1 Transgenic Mice

    PubMed Central

    Fu, You-Jun; Xiong, Shuling; Lovell, Mark A.; Lynn, Bert C.

    2010-01-01

    Accumulating evidence suggests mitochondrial alterations are intimately associated with the pathogenesis of Alzheimer’s disease (AD). To determine if mutations of presenilin-1 (PS-1) affect levels of mitochondrial proteins at different ages we enriched mitochondrial fractions from 3, 6, 12 month old knock-in mice expressing the M146V PS-1 mutation and identified, and quantified proteins using cleavable Isotope Coded Affinity Tag (ICAT) labeling and two dimensional liquid chromatography/tandem mass spectrometry (2D–LC/MS/MS). Using this approach, 165 non-redundant proteins were identified with 80 of them present in all three age groups. Specifically, at young ages (3 and 6 months), Na+/K+ ATPase and several signal transduction proteins exhibited elevated levels, but dropped dramatically at 12 months. In contrast, components of the oxidative phosporylation pathway (OXPHOS), the mitochondrial permeability transition pore (MPTP), and energy metabolism proteins remained unchanged at 3 months but significantly increased with age. We propose that alterations in calcium homeostasis induced by the PS-1 mutation have a major impact in young animals by inhibiting function of relevant proteins and inducing compensatory changes. However, in older mice combination of the PS-1 mutation and accumulated oxidative damage results in functional suppression of OXPHOS and MPTP proteins requiring a compensatory increase in expression levels. In contrast, signal transduction proteins showed decreased levels due to a break down in the compensatory mechanisms. The dysfunction of Na+/K+ ATPase and signal transduction proteins may induce impaired cognition and memory before neurodegeneration occurs. PMID:19241155

  17. The study of optical properties and proteoglycan content of tendons by PS-OCT

    NASA Astrophysics Data System (ADS)

    Yang, Ying; Rupani, Asha; Weightman, Alan; Wimpenny, Ian; Bagnaninchi, Pierre; Ahearne, Mark

    2011-03-01

    Tendons are load-bearing collagenous tissues consisting mainly of type I collagen and various proteoglycans (PGs) including decorin and versican. It is widely accepted that highly orientated collagen fibers in tendons a play critical role for transferring tensile stress and demonstrate birefringent optical properties. However, the influence that proteoglycans have on the optical properties of tendons is yet to be fully elucidated. Tendinopathy (defined as a syndrome of tendon pain, tenderness and swelling that affects the normal function of the tissue) is a common disease associated with sporting injuries or degeneration. PG's are the essential components of the tendon extracellular matrix; changes in their quantities and compositions have been associated with tendinopathy. In this study, polarization sensitive optical coherence tomography (PS-OCT) has been used to reveal the relationship between proteoglycan content/location and birefringent properties of tendons. Tendons dissected from freshly slaughtered chickens were imaged at regular intervals by PS-OCT and polarizing light microscope during the extraction of PGs or glycosaminoglycans using established protocols (guanidine hydrochloride (GuHCl) or proteinase K solution). The macroscopic and microscopic time lapsed images are complimentary; mutually demonstrating that there was a higher concentration of PG's in the outer sheath region than in the fascicles; and the integrity of the sheath affected extraction process and the OCT birefringence bands. Extraction of PGs using GuHCl disturbed the organization of local collagen bundles, which corresponded to a reduction in the frequency of birefringence bands and the band width by PS-OCT. The feature of OCT penetration depth helped us to define the heterogeneous distribution of PG's in tendon, which was complimented by polarizing light microscopy. The results provide new insight of tendon structure and also demonstrate a great potential for using PS-OCT as a

  18. Cannabis-based medicine reduces multiple pathological processes in AβPP/PS1 mice.

    PubMed

    Aso, Ester; Sánchez-Pla, Alexandre; Vegas-Lozano, Esteban; Maldonado, Rafael; Ferrer, Isidro

    2015-01-01

    Several recent findings suggest that targeting the endogenous cannabinoid system can be considered as a potential therapeutic approach to treat Alzheimer's disease (AD). The present study supports this hypothesis demonstrating that delta-9-tetrahydrocannabinol (THC) or cannabidiol (CBD) botanical extracts, as well as the combination of both natural cannabinoids, which are the components of an already approved cannabis-based medicine, preserved memory in AβPP/PS1 transgenic mice when chronically administered during the early symptomatic stage. Moreover, THC + CBD reduced learning impairment in AβPP/PS1 mice. A significant decrease in soluble Aβ42 peptide levels and a change in plaques composition were also observed in THC + CBD-treated AβPP/PS1 mice, suggesting a cannabinoid-induced reduction in the harmful effect of the most toxic form of the Aβ peptide. Among the mechanisms related with these positive cognitive effects, the anti-inflammatory properties of cannabinoids may also play a relevant role. Here we observed reduced astrogliosis, microgliosis, and inflammatory-related molecules in treated AβPP/PS1 mice, which were more marked after treatment with THC + CBD than with either THC or CBD. Moreover, other cannabinoid-induced effects were uncovered by a genome-wide gene expression study. Thus, we have identified the redox protein thioredoxin 2 and the signaling protein Wnt16 as significant substrates for the THC + CBD-induced effects in our AD model. In summary, the present findings show that the combination of THC and CBD exhibits a better therapeutic profile than each cannabis component alone and support the consideration of a cannabis-based medicine as potential therapy against AD. PMID:25125475

  19. Burkholderia phytofirmans PsJN reduces impact of freezing temperatures on photosynthesis in Arabidopsis thaliana

    PubMed Central

    Su, Fan; Jacquard, Cédric; Villaume, Sandra; Michel, Jean; Rabenoelina, Fanja; Clément, Christophe; Barka, Essaid A.; Dhondt-Cordelier, Sandrine; Vaillant-Gaveau, Nathalie

    2015-01-01

    Several plant growth-promoting rhizobacteria (PGPR) are known to improve plant tolerance to multiple stresses, including low temperatures. However, mechanisms underlying this protection are still poorly understood. The aim of this study was to evaluate the role of the endophytic PGPR, Burkholderia phytofirmans strain PsJN (Bp PsJN), on Arabidopsis thaliana cold tolerance using photosynthesis parameters as physiological markers. Under standard conditions, our results indicated that Bp PsJN inoculation led to growth promotion of Arabidopsis plants without significant modification on photosynthesis parameters and chloroplast organization. However, bacterial colonization induced a cell wall strengthening in the mesophyll. Impact of inoculation modes (either on seeds or by soil irrigation) and their effects overnight at 0, -1, or -3°C, were investigated by following photosystem II (PSII) activity and gas exchanges. Following low temperatures stress, a decrease of photosynthesis parameters was observed. In addition, during three consecutive nights or days at -1°C, PSII activity was monitored. Pigment contents, RuBisCO protein abundance, expression of several genes including RbcS, RbcL, CBF1, CBF2, CBF3, ICE1, COR15a, and COR78 were evaluated at the end of exposure. To assess the impact of the bacteria on cell ultrastructure under low temperatures, microscopic observations were achieved. Results indicated that freezing treatment induced significant changes in PSII activity as early as the first cold day, whereas the same impact on PSII activity was observed only during the third cold night. The significant effects conferred by PsJN were differential accumulation of pigments, and reduced expression of RbcL and COR78. Microscopical observations showed an alteration/disorganization in A. thaliana leaf mesophyll cells independently of the freezing treatments. The presence of bacteria during the three successive nights or days did not significantly improved A. thaliana

  20. Burkholderia phytofirmans PsJN reduces impact of freezing temperatures on photosynthesis in Arabidopsis thaliana.

    PubMed

    Su, Fan; Jacquard, Cédric; Villaume, Sandra; Michel, Jean; Rabenoelina, Fanja; Clément, Christophe; Barka, Essaid A; Dhondt-Cordelier, Sandrine; Vaillant-Gaveau, Nathalie

    2015-01-01

    Several plant growth-promoting rhizobacteria (PGPR) are known to improve plant tolerance to multiple stresses, including low temperatures. However, mechanisms underlying this protection are still poorly understood. The aim of this study was to evaluate the role of the endophytic PGPR, Burkholderia phytofirmans strain PsJN (Bp PsJN), on Arabidopsis thaliana cold tolerance using photosynthesis parameters as physiological markers. Under standard conditions, our results indicated that Bp PsJN inoculation led to growth promotion of Arabidopsis plants without significant modification on photosynthesis parameters and chloroplast organization. However, bacterial colonization induced a cell wall strengthening in the mesophyll. Impact of inoculation modes (either on seeds or by soil irrigation) and their effects overnight at 0, -1, or -3°C, were investigated by following photosystem II (PSII) activity and gas exchanges. Following low temperatures stress, a decrease of photosynthesis parameters was observed. In addition, during three consecutive nights or days at -1°C, PSII activity was monitored. Pigment contents, RuBisCO protein abundance, expression of several genes including RbcS, RbcL, CBF1, CBF2, CBF3, ICE1, COR15a, and COR78 were evaluated at the end of exposure. To assess the impact of the bacteria on cell ultrastructure under low temperatures, microscopic observations were achieved. Results indicated that freezing treatment induced significant changes in PSII activity as early as the first cold day, whereas the same impact on PSII activity was observed only during the third cold night. The significant effects conferred by PsJN were differential accumulation of pigments, and reduced expression of RbcL and COR78. Microscopical observations showed an alteration/disorganization in A. thaliana leaf mesophyll cells independently of the freezing treatments. The presence of bacteria during the three successive nights or days did not significantly improved A. thaliana

  1. PM200/PS200: Self-Lubricating Bearing and Seal Materials for Applications to 900 C

    NASA Technical Reports Server (NTRS)

    Sliney, Harold E.

    1991-01-01

    The development of the PS/PM200 class of self-lubricating material is described. The composition of the materials and their performance under temperature conditions from minus 160 degrees to 900 C (minus 250 to 1650 F) are examined. Applications in areas such as cylinder liner coatings, shaft seals, gas bearings, and airframe thermal expansion joints are proposed. Graphs and tables are provided to show service temperature limits, mechanical strength, linear thermal expansion, and thermal conductivity parameters.

  2. Joint Use of PP and PS AVOA Data to Estimate Fluid Indicator in Vertically Fractured Medium

    NASA Astrophysics Data System (ADS)

    Pan, B.; Sen, M. K.; Gu, H.

    2015-12-01

    The existence of fractures induces anisotropy in medium. This anisotropy might be a comprehensive result of fractures' properties, such as the direction, spacing, apertures, intensity, microstructure, fluid infill, and so on. Among these properties, the preferential orientation of fracture networks makes the medium azimuthally anisotropic with respect to seismic wave propagation. To the medium containing a set of vertical fractures, the tangential weakness does not vary with the fluid content, however on which the normal weakness shows great dependence. Based on the theory of linear slip model and the sensitivity to fracture weakness of PP- and PS-reflection coefficients which can be derived by a Born formula, we did both the PP-AVOA and PS-AVOA numerical experiment and also the joint inversion of fluid indicator. Results show that when the fractures have low saturation of gas, the fluid indicator estimated from PP-AVOA data is precise enough; when gas saturation goes up to 70%, joint inversion can help to improve the poor quality of PP-AVOA data inversion. Under high gas-saturated case, both PP inversion and joint inversion are sensitive to the errors in g, where g is the square of the ratio of S- and P- wave velocity in the unfractured medium. This dependency can be reduced by adding a different weight to PP and PS data during the inversion.Based on the result of numerical experiment, we processed field data in Sichuan Basin in China. The inversion result is consistent with the well interpretation. The first column in figure represents the PP- and PS-reflectivity computed by matrix method(Fryer and Frazer,1984). The second column is the result of Born linearized method. In the last column, upper one shows the estimated fluid indicator in different gas saturation case and the below one consider the effect of error in g on the inversion results.

  3. SESAM-modelocked electrically pumped VECSELs emitting 6.3-ps pulses

    NASA Astrophysics Data System (ADS)

    Zaugg, C. A.; Pallmann, W. P.; Mangold, M.; Dahhan, I.; Golling, M.; Tilma, B. W.; Witzigmann, B.; Keller, U.

    2014-03-01

    Optically pumped vertical external cavity surface emitting lasers (OP-VECSELs) evolved to high-power laser sources offering excellent beam-quality, wavelength flexibility and low-noise properties in a compact and simple cavity. Passively modelocked with a semiconductor saturable absorber mirror (SESAM), VECSELs demonstrated fs-pulses with multi-Watt average output powers at gigahertz repetition rates. Electrical pumping (EP) is an obvious step to make these semiconductor lasers even more compact and suitable for chip integration, potentially enabling access to applications such as data communication or optical clocking. With SESAMmodelocked EP-VECSELs, 57-ps pulses with an average output power of 40 mW and 9.5-ps pulses with 7.6 mW have been obtained. However, due to the intrinsic trade-off between electrical and optical properties in the design of EPVECSELs, short pulses at high average output power are difficult to achieve. This challenge was previously addressed in our theoretical guidelines for power scaling and modelocking optimization and later experimentally verified. Here, we report on the successful implementation of an improved design and fabrication scheme for EP-VECSELs, grown and fabricated at ETH Zurich. These lasers enabled a further decrease in pulse duration to 7.3 ps while increasing the average output power to 13.1 mW at 1.46-GHz repetition rate. The shortest pulse duration measured was 6.3 ps with an average power of 6.2 mW. In addition to the modelocking experiments, we present a thorough cw-characterization of our EP-VECSELs of different sizes and in different cavity configurations, pointing out the inevitable trade-off between high-power multi-mode and low-power single-mode operation limiting the modelocking performance.

  4. Cloud Computing for Pharmacometrics: Using AWS, NONMEM, PsN, Grid Engine, and Sonic

    PubMed Central

    Sanduja, S; Jewell, P; Aron, E; Pharai, N

    2015-01-01

    Cloud computing allows pharmacometricians to access advanced hardware, network, and security resources available to expedite analysis and reporting. Cloud-based computing environments are available at a fraction of the time and effort when compared to traditional local datacenter-based solutions. This tutorial explains how to get started with building your own personal cloud computer cluster using Amazon Web Services (AWS), NONMEM, PsN, Grid Engine, and Sonic. PMID:26451333

  5. Cloud Computing for Pharmacometrics: Using AWS, NONMEM, PsN, Grid Engine, and Sonic.

    PubMed

    Sanduja, S; Jewell, P; Aron, E; Pharai, N

    2015-09-01

    Cloud computing allows pharmacometricians to access advanced hardware, network, and security resources available to expedite analysis and reporting. Cloud-based computing environments are available at a fraction of the time and effort when compared to traditional local datacenter-based solutions. This tutorial explains how to get started with building your own personal cloud computer cluster using Amazon Web Services (AWS), NONMEM, PsN, Grid Engine, and Sonic. PMID:26451333

  6. Technological Overview of iPS Induction from Human Adult Somatic Cells

    PubMed Central

    Bayart, Emilie; Cohen-Haguenauer, Odile

    2013-01-01

    The unlimited proliferation capacity of embryonic stem cells (ESCs) combined with their pluripotent differentiation potential in various lineages raised great interest in both the scientific community and the public at large with hope for future prospects of regenerative medicine. However, since ESCs are derived from human embryos, their use is associated with significant ethical issues preventing broad studies and therapeutic applications. To get around this bottleneck, Takahashi and Yamanaka have recently achieved the conversion of adult somatic cells into ES-like cells via the forced expression of four transcription factors: Oct3/4, Sox2, Klf4 and c-Myc. This first demonstration attracted public attention and opened a new field of stem cells research with both cognitive – such as disease modeling - and therapeutic prospects. This pioneer work just received the 2012 Nobel Prize in Physiology or Medicine. Many methods have been reported since 2006, for the generation of induced pluripotent stem (iPS) cells. Most strategies currently under use are based on gene delivery via gamma-retroviral or lentiviral vectors; some experiments have also been successful using plasmids or transposons-based systems and few with adenovirus. However, most experiments involve integration in the host cell genome with an identified risk for insertional mutagenesis and oncogenic transformation. To circumvent such risks which are deemed incompatible with therapeutic prospects, significant progress has been made with transgene-free reprogramming methods based on e.g.: sendaï virus or direct mRNA or protein delivery to achieve conversion of adult cells into iPS. In this review we aim to cover current knowledge relating to both delivery systems and combinations of inducing factors including chemicals which are used to generate human iPS cells. Finally, genetic instability resulting from the reprogramming process is also being considered as a safety bottleneck for future clinical

  7. E-Cloud Effects on Singe-Bunch Dynamics in the Proposed PS2

    SciTech Connect

    Venturini, M.; Furman, M.; Vay, J.-L.

    2010-10-08

    One of the options considered for future upgrades of the LHC injector complex entails the replacement of the PSwith the PS2, a longer circumference and higher energy synchrotron. Electron cloud effects represent an importantpotential limitation to the achievement of the upgrade goals. We report the results of numerical studies aimingat estimating the e-cloud density thresholds for the occurrence of single bunch instabilities.

  8. Technological overview of iPS induction from human adult somatic cells.

    PubMed

    Bayart, Emilie; Cohen-Haguenauer, Odile

    2013-04-01

    The unlimited proliferation capacity of embryonic stem cells (ESCs) combined with their pluripotent differentiation potential in various lineages raised great interest in both the scientific community and the public at large with hope for future prospects of regenerative medicine. However, since ESCs are derived from human embryos, their use is associated with significant ethical issues preventing broad studies and therapeutic applications. To get around this bottleneck, Takahashi and Yamanaka have recently achieved the conversion of adult somatic cells into ES-like cells via the forced expression of four transcription factors: Oct3/4, Sox2, Klf4 and c-Myc. This first demonstration attracted public attention and opened a new field of stem cells research with both cognitive - such as disease modeling - and therapeutic prospects. This pioneer work just received the 2012 Nobel Prize in Physiology or Medicine. Many methods have been reported since 2006, for the generation of induced pluripotent stem (iPS) cells. Most strategies currently under use are based on gene delivery via gamma-retroviral or lentiviral vectors; some experiments have also been successful using plasmids or transposons- based systems and few with adenovirus. However, most experiments involve integration in the host cell genome with an identified risk for insertional mutagenesis and oncogenic transformation. To circumvent such risks which are deemed incompatible with therapeutic prospects, significant progress has been made with transgene-free reprogramming methods based on e.g.: sendai virus or direct mRNA or protein delivery to achieve conversion of adult cells into iPS. In this review we aim to cover current knowledge relating to both delivery systems and combinations of inducing factors including chemicals which are used to generate human iPS cells. Finally, genetic instability resulting from the reprogramming process is also being considered as a safety bottleneck for future clinical translation

  9. FLOYDS Classification of ASASSN-15ps as a Type Ia Supernova Near Peak

    NASA Astrophysics Data System (ADS)

    Hosseinzadeh, G.; Smartt, S. J.; Arcavi, I.; Howell, D. A.; McCully, C.; Valenti, S.

    2015-09-01

    We obtained a spectrum of ASASSN-15ps (ATel #8066) on 2015 September 20.7 UT with the robotic FLOYDS instrument mounted on the Faulkes Telescope South. Using SNID (Blondin & Tonry 2007, ApJ, 666, 1024), we find several good fits to the normal Type Ia SN 1998aq 2-6 days after maximum light at redshifts around z=0.04.

  10. Effects of Folic Acid on Secretases Involved in Aβ Deposition in APP/PS1 Mice.

    PubMed

    Tian, Tian; Bai, Dong; Li, Wen; Huang, Guo-Wei; Liu, Huan

    2016-01-01

    Alzheimer's disease (AD) is the most common type of dementia. Amyloid-β protein (Aβ) is identified as the core protein of neuritic plaques. Aβ is generated by the sequential cleavage of the amyloid precursor protein (APP) via the APP cleaving enzyme (α-secretase, or β-secretase) and γ-secretase. Previous studies indicated that folate deficiency elevated Aβ deposition in APP/PS1 mice, and this rise was prevented by folic acid. In the present study, we aimed to investigate whether folic acid could influence the generation of Aβ by regulating α-, β-, and γ-secretase. Herein, we demonstrated that folic acid reduced the deposition of Aβ42 in APP/PS1 mice brain by decreasing the mRNA and protein expressions of β-secretase [beta-site APP-cleaving enzyme 1 (BACE1)] and γ-secretase complex catalytic component-presenilin 1 (PS1)-in APP/PS1 mice brain. Meanwhile, folic acid increased the levels of ADAM9 and ADAM10, which are important α-secretases in ADAM (a disintegrin and metalloprotease) family. However, folic acid has no impact on the protein expression of nicastrin (Nct), another component of γ-secretase complex. Moreover, folic acid regulated the expression of miR-126-3p and miR-339-5p, which target ADAM9 and BACE1, respectively. Taken together, the effect of folic acid on Aβ deposition may relate to making APP metabolism through non-amyloidogenic pathway by decreasing β-secretase and increasing α-secretase. MicroRNA (miRNA) may involve in the regulation mechanism of folic acid on secretase expression. PMID:27618097

  11. Control and readout of the extraction septum of AmPS

    NASA Astrophysics Data System (ADS)

    Vanes, J. T.; Luigjes, G.; Vantrigt, J. H.

    The electronics used for the septum translation-rotation control system and for the control of the 100 kV power supply of the electrostatic septum of the storage ring AmPS (Amsterdam Pulse Stretcher) are described. The translation and rotation of the septum are performed by stepping motors controlled by LVDT's (Linear Variable Differential Transformers), which are controlled by a bitbus module which also controls the high voltage power supply.

  12. STS-47 PS Mohri uses sky genie during post landing egress training at JSC

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-47 Endeavour, Orbiter Vehicle (OV) 105, Spacelab Japan (SLJ) Payload Specialist (PS) Mamoru Mohri, wearing launch and entry suit (LES) and launch and entry helmet (LEH), operates sky genie equipment. Mohri is participating in post landing egress training exercises at JSC's Mockup and Integration Laboratory (MAIL) Bldg 9NE. Mohri has exited the Crew Compartment Trainer (CCT) mockup through an overhead window and now uses the sky genie to lower himself to the ground. Mohri represents Japan's National Space Development Agency (NASDA).

  13. Generation and In Vitro Expansion of Hepatic Progenitor Cells from Human iPS Cells.

    PubMed

    Yanagida, Ayaka; Nakauchi, Hiromitsu; Kamiya, Akihide

    2016-01-01

    Stem cells have the unique properties of self-renewal and multipotency (producing progeny belonging to two or more lineages). Induced pluripotent stem (iPS) cells can be generated from somatic cells by simultaneous expression of pluripotent factors (Oct3/4, Klf4, Sox2, and c-Myc). They share the same properties as embryonic stem (ES) cells and can differentiate into several tissue cells, i.e., neurons, hematopoietic cells, and liver cells. Therefore, iPS cells are suitable candidate cells for regenerative medicine and analyses of disease mechanisms.The liver is the major organ that regulates a multitude of metabolic functions. Hepatocytes are the major cell type populating the liver parenchyma and express several metabolic enzymes that are necessary for liver functions. Although hepatocytes are essential for maintaining homeostasis, it is difficult to alter artificial and transplanted cells because of their multifunctionality, donor shortage, and immunorejection risk. During liver development, hepatic progenitor cells in the fetal liver differentiate into both mature hepatocytes and cholangiocytes. As hepatic progenitor cells have bipotency and high proliferation ability, they could present a potential source for generating transplantable cells or as a liver study model. Here we describe the induction and purification of hepatic progenitor cells derived from human iPS cells. These cells can proliferate for a long term under suitable culture conditions. PMID:25697415

  14. Effect of reactive monomer on PS-b-P2VP film with UV irradiation

    NASA Astrophysics Data System (ADS)

    Kim, H. J.; Shin, D. M.

    2012-03-01

    Poly(styrene-b-2-vinyl pyridine) (PS-b-P2VP) lamellar film which is hydrophobic block hydrophilic polyelectrolyte block polymer of 52 kg/mol -b- 57 kg/mol and PS-b-P2VP film with reactive monomer (RM257) were prepared for photonic gel films. The lamellar stacks, which is alternating layer of hydrophilic and hydrophobic part of PS-b-P2VP. We reported about the influence of reactive monomer on those photonic gel films. Added reactive monomer photonic gel film had higher absorbance than pure photonic gel films. And band gaps of the lamellar films shifted by the time of UV light irradiation. That Photonic gel films were measured with the UV spectrophotometer. As a result the photonic gel film with reactive monomer had more clear color. The lamellar films were swollen by DI water, Ethyl alcohol (aq) and calcium carbonate solution. Since the domain spacing of dried photonic gel films were not showing any color in visible wavelength. The band gap of the lamellar films were drastically shifted to longer wavelength swollen by calcium carbonate solution (absorbance peak 565nm-->617nm). And the lamellar films were shifted to shorter wave length swollen by ethanol (absorbance peak 565nm-->497nm). So each Photonic gel film showed different color.

  15. Effects of curcumin on synapses in APPswe/PS1dE9 mice.

    PubMed

    He, Yingkun; Wang, Pengwen; Wei, Peng; Feng, Huili; Ren, Ying; Yang, Jinduo; Rao, Yingxue; Shi, Jing; Tian, Jinzhou

    2016-06-01

    Significant losses of synapses have been demonstrated in studies of Alzheimer's disease (AD), but structural and functional changes in synapses that depend on alterations of the postsynaptic density (PSD) area occur prior to synaptic loss and play a crucial role in the pathology of AD. Evidence suggests that curcumin can ameliorate the learning and memory deficits of AD. To investigate the effects of curcumin on synapses, APPswe/PS1dE9 double transgenic mice (an AD model) were used, and the ultra-structures of synapses and synapse-associated proteins were observed. Six months after administration, few abnormal synapses were observed upon electron microscopy in the hippocampal CA1 areas of the APPswe/PS1dE9 double transgenic mice. The treatment of the mice with curcumin resulted in improvements in the quantity and structure of the synapses. Immunohistochemistry and western blot analyses revealed that the expressions of PSD95 and Shank1 were reduced in the hippocampal CA1 areas of the APPswe/PS1dE9 double transgenic mice, but curcumin treatment increased the expressions of these proteins. Our findings suggest that curcumin improved the structure and function of the synapses by regulating the synapse-related proteins PSD95 and Shank1. PMID:26957323

  16. LCAT deficiency does not impair amyloid metabolism in APP/PS1 mice.

    PubMed

    Stukas, Sophie; Freeman, Lita; Lee, Michael; Wilkinson, Anna; Ossoli, Alice; Vaisman, Boris; Demosky, Stephen; Chan, Jeniffer; Hirsch-Reinshagen, Veronica; Remaley, Alan T; Wellington, Cheryl L

    2014-08-01

    A key step in plasma HDL maturation from discoidal to spherical particles is the esterification of cholesterol to cholesteryl ester, which is catalyzed by LCAT. HDL-like lipoproteins in cerebrospinal fluid (CSF) are also spherical, whereas nascent lipoprotein particles secreted from astrocytes are discoidal, suggesting that LCAT may play a similar role in the CNS. In plasma, apoA-I is the main LCAT activator, while in the CNS, it is believed to be apoE. apoE is directly involved in the pathological progression of Alzheimer's disease, including facilitating β-amyloid (Aβ) clearance from the brain, a function that requires its lipidation by ABCA1. However, whether apoE particle maturation by LCAT is also required for Aβ clearance is unknown. Here we characterized the impact of LCAT deficiency on CNS lipoprotein metabolism and amyloid pathology. Deletion of LCAT from APP/PS1 mice resulted in a pronounced decrease of apoA-I in plasma that was paralleled by decreased apoA-I levels in CSF and brain tissue, whereas apoE levels were unaffected. Furthermore, LCAT deficiency did not increase Aβ or amyloid in APP/PS1 LCAT(-/-) mice. Finally, LCAT expression and plasma activity were unaffected by age or the onset of Alzheimer's-like pathology in APP/PS1 mice. Taken together, these results suggest that apoE-containing discoidal HDLs do not require LCAT-dependent maturation to mediate efficient Aβ clearance. PMID:24950691

  17. iPS-cell derived dendritic cells and macrophages for cancer therapy.

    PubMed

    Senju, Satoru

    2016-08-01

    Antibody-based anti-cancer immunotherapy was recently recognized as one of the truly effective therapies for cancer patients. Antibodies against cell surface cancer antigens, such as CD20, and also those against immune-inhibitory molecules called "immune checkpoint blockers", such as CTLA4 or PD1, have emerged. Large-scale clinical trials have confirmed that, in some cases, antibody-based drugs are superior to conventional chemotherapeutic agents. These antibody-based drugs are now being manufactured employing a mass-production system by pharmaceutical companies. Anti-cancer therapy by immune cells, i.e. cell-based immunotherapy, is expected to be more effective than antibody therapy, because immune cells can recognize, infiltrate, and act in cancer tissues more directly than antibodies. In order to achieve cell-based anti-cancer immunotherapy, it is necessary to develop manufacturing systems for mass-production of immune cells. Our group has been studying immunotherapy with myeloid cells derived from ES cells or iPS cells. These pluripotent stem cells can be readily propagated under constant culture conditions, with expansion into a large quantity. We consider these stem cells to be the most suitable cellular source for mass-production of immune cells. This review introduces our studies on anti-cancer therapy with iPS cell-derived dendritic cells and iPS cell-derived macrophages. PMID:27599426

  18. High aspect ratio PS-b-PMMA block copolymer masks for lithographic applications.

    PubMed

    Ferrarese Lupi, F; Giammaria, T J; Volpe, F G; Lotto, F; Seguini, G; Pivac, B; Laus, M; Perego, M

    2014-12-10

    The control of the self-assembly (SA) process and nanostructure orientation in diblock copolymer (DBC) thick films is a crucial technological issue. Perpendicular orientation of the nanostructures in symmetric and asymmetric poly(styrene)-b-poly(methyl methacrylate) (PS-b-PMMA) block copolymer films obtained by means of simple thermal treatments was demonstrated to occur in well-defined thickness windows featuring modest maximum values, thus resulting in low aspect ratio (h/d < 2) of the final lithographic mask. In this manuscript, the thickness window corresponding to the perpendicular orientation of the cylindrical structures in asymmetric DBC is investigated at high temperatures (190 °C ≤ T ≤ 310 °C) using a rapid thermal processing machine. A systematic study of the annealing conditions (temperature and time) of asymmetric PS-b-PMMA (Mn = 67.1, polydispersity index = 1.09) films, with thicknesses ranging from 10 to 400 nm, allowed ordered patterns, with a maximum value of orientational correlation length of 350 nm, to be obtained for film thicknesses up to 200 nm. The complete propagation of the cylindrical structures through the whole film thickness in a high aspect ratio PS template (h/d ≈ 7) is probed by lift-off process. Si nanopillars are obtained having the same lateral ordering and characteristic dimensions of the DBC lithographic mask as further confirmed by grazing-incidence small-angle X-ray scattering experiments. PMID:25387131

  19. Hypothalamic S1P/S1PR1 axis controls energy homeostasis.

    PubMed

    Silva, Vagner R R; Micheletti, Thayana O; Pimentel, Gustavo D; Katashima, Carlos K; Lenhare, Luciene; Morari, Joseane; Mendes, Maria Carolina S; Razolli, Daniela S; Rocha, Guilherme Z; de Souza, Claudio T; Ryu, Dongryeol; Prada, Patrícia O; Velloso, Lício A; Carvalheira, José B C; Pauli, José Rodrigo; Cintra, Dennys E; Ropelle, Eduardo R

    2014-01-01

    Sphingosine 1-phosphate receptor 1 (S1PR1) is a G-protein-coupled receptor for sphingosine-1-phosphate (S1P) that has a role in many physiological and pathophysiological processes. Here we show that the S1P/S1PR1 signalling pathway in hypothalamic neurons regulates energy homeostasis in rodents. We demonstrate that S1PR1 protein is highly enriched in hypothalamic POMC neurons of rats. Intracerebroventricular injections of the bioactive lipid, S1P, reduce food consumption and increase rat energy expenditure through persistent activation of STAT3 and the melanocortin system. Similarly, the selective disruption of hypothalamic S1PR1 increases food intake and reduces the respiratory exchange ratio. We further show that STAT3 controls S1PR1 expression in neurons via a positive feedback mechanism. Interestingly, several models of obesity and cancer anorexia display an imbalance of hypothalamic S1P/S1PR1/STAT3 axis, whereas pharmacological intervention ameliorates these phenotypes. Taken together, our data demonstrate that the neuronal S1P/S1PR1/STAT3 signalling axis plays a critical role in the control of energy homeostasis in rats. PMID:25255053

  20. Thermal Effects on a Low Cr Modification of PS304 Solid Lubricant Coating

    NASA Technical Reports Server (NTRS)

    Stanford, Malcolm K.; Yanke, Anne M.; DellaCorte, Christopher

    2004-01-01

    PS304 is a high temperature composite solid lubricant coating composed of Ni-Cr, Cr2O3, BaF2-CaF2 and Ag. The effect of reducing chromium content on the formation of voids in the Ni-Cr particles after heat treatment in PS304 coating was investigated. Coatings were prepared with Ni-20Cr or Ni-10Cr powder and in various combinations with the other constituents of PS304 (i.e., chromia, silver and eutectic BaF2-CaF2 powders) and deposited on metal substrates by plasma spray. Specimens were exposed to 650 C for 24 hr or 1090 C for 15 hr and then examined for changes in thickness, coating microstructure and adhesion strength. Specimens with Ni-10Cr generally had less thickness increase than specimens with Ni-20Cr, but there was great variance in the data. Reduction of chromium concentration in Ni-Cr powder tended to reduce the appearance of voids in the Ni-Cr phase after heat exposure. The presence of BaF2-CaF2 resulted in a significant increase in coating adhesion strength after heat treatment, while coatings without BaF2-CaF2 had no significant change. Chemical composition analysis suggested that the void formation was due to oxidation of chromium in the Ni-Cr constituent.

  1. Quantitative analysis of intraneuronal transport in human iPS neurons.

    PubMed

    Nakamura, Haruko; Yamashita, Naoya; Kanamaru, Yuri; Tachibana, Takahiko; Sekino, Yuko; Chen, Sandy; Gotoh, Toshiyuki; Tanaka, Fumiaki; Goshima, Yoshio

    2015-08-01

    Induced pluripotent stem (iPS) cells are promising tools to investigate disease mechanism and develop new drugs. Intraneuronal transport, which is fundamental for neuronal survival and function, is vulnerable to various pharmacological and chemical agents and is disrupted in some neurodegenerative disorders. We applied a quantification method for axonal transport by counting CM-DiI-labeled particles traveling along the neurite, which allowed us to monitor and quantitate, for the first time, intraneuronal transport in human neurons differentiated from iPS cells (iCell neurons). We evaluated the acute effects of several anti-neoplastic agents that have been previously shown to affect intraneuronal transport. Vincristine, paclitaxel and oxaliplatin decreased the number of moving particle along neurites. Cisplatin, however, produced no effect on intraneuronal transport, which is in contrast to our previous report indicating that it inhibits transport in chick dorsal root ganglion neurons. Our system may be a useful method for assessing intraneuronal transport and neurotoxicity in human iPS neurons. PMID:26232861

  2. The Limits of Lamellae-Forming PS-b-PMMA Block Copolymers for Lithography.

    PubMed

    Wan, Lei; Ruiz, Ricardo; Gao, He; Patel, Kanaiyalal C; Albrecht, Thomas R; Yin, Jian; Kim, Jihoon; Cao, Yi; Lin, Guanyang

    2015-07-28

    We explore the lithographic limits of lamellae-forming PS-b-PMMA block copolymers by performing directed self-assembly and pattern transfer on a range of PS-b-PMMA materials having a full pitch from 27 to 18.5 nm. While directed self-assembly on chemical contrast patterns was successful with all the materials used in this study, clean removal of PMMA domains and subsequent pattern transfer could only be sustained down to 22 nm full pitch. We attribute this limitation to the width of the interface, which may represent more than half of the domain width for materials with a critical dimension below 10 nm. With the limit of pattern transfer for PS-b-PMMA set at ∼11 nm, we propose an integration scheme suitable for bit patterned media for densities above 1.6 Tdot/in(2), which require features below this limit. Directed self-assembly was carried out on chemical contrast patterns made by a rotary e-beam lithography system, and pattern transfer was carried out to demonstrate fabrication of large area (up to 25 mm-wide annular band of circular tracks) nanoimprint templates for bit patterned media. We also demonstrate compatibility with hard disk drive architecture by fabricating patterns with skewed radial lines with constant angular pitch and with servo patterns that are needed in hard disk drives to generate a radial positional error signal (PES). PMID:26046475

  3. Particle Size Effects on Flow Properties of PS304 Plasma Spray Feedstock Powder Blend

    NASA Technical Reports Server (NTRS)

    Stanford, Malcolm K.; DellaCorte, Christopher; Eylon, Daniel

    2002-01-01

    The effects of BaF2-CaF2 particle size and size distribution on PS304 feedstock powder flowability have been investigated. Angular BaF2-CaF2 eutectic powders were produced by comminution and classified by screening to obtain 38 to 45 microns 45 to 106 microns, 63 to 106 microns, 45 to 53 microns, 63 to 75 microns, and 90 to 106 microns particle size distributions. The fluorides were added incrementally from 0 to 10 wt% to the other powder constituents of the PS304 feedstock: nichrome, chromia, and silver powders. The flow rate of the powder blends decreased linearly with increasing concentration of the fluorides. Flow was degraded with decreasing BaF2-CaF2 particle size and with increasing BaF2-CaF2 particle size distribution. A semiempirical relationship is offered to describe the PS304 powder blend flow behavior. The Hausner Ratio confirmed the funnel flow test results, but was slightly less sensitive to differences in BaF2-CaF2 particle size and size distribution. These findings may have applicability to other powders that do not flow easily, such as ceramic powders.

  4. Redetermination of AgNb2PS10 revealing a silver deficiency

    PubMed Central

    Do, Junghwan; Yun, Hoseop

    2009-01-01

    In comparison with a previous crystallographic study [Goh et al. (2002 ▶). J. Solid State Chem. 168, 119–125] of the title compound, silver diniobium tris­(disulfide) tetra­thio­phosphate(V), that reports a full occupation of the silver position and isotropic displacement parameters for the atoms, the current redetermination reveals a silver deficiency with a site-occupation factor of 0.88 (1) and reports all atoms with anisotropic displacement parameters. The structure of Ag0.88Nb2PS10 is composed of ∞ 1[Nb2PS10] chains, which are built up from pairs of distorted bicapped trigonal-prismatic [NbS8] polyhedra forming [Nb2S12] dimers and of tetra­hedral [PS4] groups. These chains are connected via the statistically disordered Ag+ ions, forming double layers. Adjacent layers are stacked solely through van der Waals forces into a three-dimensional structure. Short and long Nb—Nb distances [2.880 (1) and 3.770 (2) Å, respectively] alternate along the chain and S2 2− and S2− anionic species are observed. PMID:21583293

  5. Public Health Impact After the Introduction of PsA-TT: The First 4 Years

    PubMed Central

    Diomandé, Fabien V. K.; Djingarey, Mamoudou H.; Daugla, Doumagoum M.; Novak, Ryan T.; Kristiansen, Paul A.; Collard, Jean-Marc; Gamougam, Kadidja; Kandolo, Denis; Mbakuliyemo, Nehemie; Mayer, Leonard; Stuart, James; Clark, Thomas; Tevi-Benissan, Carol; Perea, William A.; Preziosi, Marie-Pierre; Marc LaForce, F.; Caugant, Dominique; Messonnier, Nancy; Walker, Oladapo; Greenwood, Brian

    2015-01-01

    Background. During the first introduction of a group A meningococcal vaccine (PsA-TT) in 2010–2011 and its rollout from 2011 to 2013, >150 million eligible people, representing 12 hyperendemic meningitis countries, have been vaccinated. Methods. The new vaccine effectiveness evaluation framework was established by the World Health Organization and partners. Meningitis case-based surveillance was strengthened in PsA-TT first-introducer countries, and several evaluation studies were conducted to estimate the vaccination coverage and to measure the impact of vaccine introduction on meningococcal carriage and disease incidence. Results. PsA-TT implementation achieved high vaccination coverage, and results from studies conducted showed significant decrease of disease incidence as well as significant reduction of oropharyngeal carriage of group A meningococci in vaccinated and unvaccinated individuals, demonstrating the vaccine's ability to generate herd protection and prevent group A epidemics. Conclusions. Lessons learned from this experience provide useful insights in how to guide and better prepare for future new vaccine introductions in resource-limited settings. PMID:26553676

  6. Modeling of MHD edge containment in strip casting with ELEKTRA and CaPS-EM codes

    SciTech Connect

    Chang, F. C.

    2000-01-12

    This paper presents modeling studies of magnetohydrodynamics analysis in twin-roll casting. Argonne National Laboratory (ANL) and ISPAT Inland Inc. (Inland), formerly Inland Steel Co., have worked together to develop a three-dimensional (3-D) computer model that can predict eddy currents, fluid flows, and liquid metal containment of an electromagnetic (EM) edge containment device. The model was verified by comparing predictions with experimental results of liquid metal containment and fluid flow in EM edge dams (EMDs) that were designed at Inland for twin-roll casting. This mathematical model can significantly shorten casting research on the use of EM fields for liquid metal containment and control. The model can optimize the EMD design so it is suitable for application, and minimize expensive time-consuming full-scale testing. Numerical simulation was performed by coupling a 3-D finite-element EM code (ELEKTRA) and a 3-D finite-difference fluids code (CaPS-EM) to solve heat transfer, fluid flow, and turbulence transport in a casting process that involves EM fields. ELEKTRA can predict the eddy-current distribution and the EM forces in complex geometries. CaPS-EM can model fluid flows with free surfaces. The computed 3-D magnetic fields and induced eddy currents in ELEKTRA are used as input to temperature- and flow-field computations in CaPS-EM. Results of the numerical simulation compared well with measurements obtained from both static and dynamic tests.

  7. NASA PS304 Lubricant Tested in World's First Commercial Oil-Free Gas Turbine

    NASA Technical Reports Server (NTRS)

    Weaver, Harold F.

    2003-01-01

    In a marriage of research and commercial technology, a 30-kW Oil-Free Capstone microturbine electrical generator unit has been installed and is serving as a test bed for long-term life-cycle testing of NASA-developed PS304 shaft coatings. The coatings are used to reduce friction and wear of the turbine engine s foil air bearings during startup and shut down when sliding occurs, prior to the formation of a lubricating air film. This testing supports NASA Glenn Research Center s effort to develop Oil-Free gas turbine aircraft propulsion systems, which will employ advanced foil air bearings and NASA s PS304 high temperature solid lubricant to replace the ball bearings and lubricating oil found in conventional engines. Glenn s Oil-Free Turbomachinery team s current project is the demonstration of an Oil-Free business jet engine. In anticipation of future flight certification of Oil-Free aircraft engines, long-term endurance and durability tests are being conducted in a relevant gas turbine environment using the Capstone microturbine engine. By operating the engine now, valuable performance data for PS304 shaft coatings and for industry s foil air bearings are being accumulated.

  8. Photoactivated electronic activities of Photosystem I (PS I) immobilized on self-assembled monolayer/gold substrates

    NASA Astrophysics Data System (ADS)

    Mukherjee, Dibyendu; Ivanov, Ilia; Khomami, Bamin

    2012-02-01

    Photosynthetic protein complex, Photosystem I (PS I) activates a light-induced (λ=680 nm) directional electron transfer chain that initiates at the lumenal side (mid-point potential, Em(P700/ P700+)˜+0.4 V) and terminates at the stromal side (Em(FA; FB; FX)˜-0.7 V) of PS I. In an effort to harness this photo-electrochemical activity of PS I in future bio-hybrid photovoltaic devices, precise electrochemical measurements have been used to investigate the photo-activated properties of PS I monolayers assembled on C9-alkanethiolate SAM/Au substrates. These measurements demonstrate, for the first time, a light-induced energetic electron transfer from the Au donor facilitated by photoexcitation of the reaction center P700 in PS I complexes. Furthermore, electrochemical impedance spectroscopy measurements, when fitted with equivalent electrical circuit models, reveal a light-induced reduction in the charge transfer resistance at the PS I/SAM-electrolyte interface. These observations, in conjunction with measurements for the transient electronic behavior, reveal the underlying mechanistic picture for the photo-excited electronic activities in PS I monolayer assembly on SAM/Au substrates.

  9. Acetylation-dependent regulation of essential iPS-inducing factors: a regulatory crossroad for pluripotency and tumorigenesis

    PubMed Central

    Dai, Xiangpeng; Liu, Pengda; Lau, Alan W; Liu, Yueyong; Inuzuka, Hiroyuki

    2014-01-01

    Induced pluripotent stem (iPS) cells can be generated from somatic cells by coexpression of four transcription factors: Sox2, Oct4, Klf4, and c-Myc. However, the low efficiency in generating iPS cells and the tendency of tumorigenesis hinder the therapeutic applications for iPS cells in treatment of human diseases. To this end, it remains largely unknown how the iPS process is subjected to regulation by upstream signaling pathway(s). Here, we report that Akt regulates the iPS process by modulating posttranslational modifications of these iPS factors in both direct and indirect manners. Specifically, Akt directly phosphorylates Oct4 to modulate the Oct4/Sox2 heterodimer formation. Furthermore, Akt either facilitates the p300-mediated acetylation of Oct4, Sox2, and Klf4, or stabilizes Klf4 by inactivating GSK3, thus indirectly modulating stemness. As tumorigenesis shares possible common features and mechanisms with iPS, our study suggests that Akt inhibition might serve as a cancer therapeutic approach to target cancer stem cells. PMID:25116380

  10. Crystal structure of the mixed-metal thio-phosphate Nb1.18V0.82PS10.

    PubMed

    Sun, Joobin; Heo, Jiyun; Yun, Hoseop

    2015-03-01

    The mixed-metal thio-phosphate, Nb1.18V0.82PS10 (niobium vanadium phospho-rus deca-sulfide), has been prepared though solid state reactions using an alkali-metal halide flux. The title compound is isostructural with two-dimensional Nb2PS10. [M 2S12] (M = Nb or V) dimers built up from two bicapped trigonal prisms and tetra-hedral [PS4] units share sulfur atoms to construct (1) ∞[M 2PS10] chains along the a axis. These chains are linked through the di-sulfide bonds between [PS4] units in adjacent chains to form layers parallel to the ab plane. These layers then stack on top of each other to complete the three-dimensional structure with van der Waals gaps. The M sites are occupied by 59% of Nb and 41% of V and the average M-S and M-M distances in the title compound are in between those of V2PS10 and Nb2PS10. The classical charge balance of the title compound can be represented by [(Nb/V)(4+)]2[P(5+)][S(2-)]3[S(-)]7. PMID:25844187

  11. Opto-electronic properties of a TiO2/PS/mc-Si heterojunction based solar cell

    NASA Astrophysics Data System (ADS)

    Janene, N.; Ghrairi, N.; Allagui, A.; Alawadhi, H.; Khakani, M. A. El; Bessais, B.; Gaidi, M.

    2016-04-01

    In this work, we show the results of our investigation on the photoelectric properties of heterojunction solar cells based on Au/PS/mc-Si/Al and Au/TiO2/PS/mc-Si/Al structures. Porous silicon (PS) were prepared by an electrochemical etching process with different values of current density. The surface porosity was found to increase with the increase of current density. Pulsed laser deposition was used to deposit 80 nm TiO2 thin films. Surface morphology and structural properties of TiO2/PS were characterized by using scanning electron microscopy (SEM) and atomic force microscopy (AFM). An enhancement of the electrical properties of the TiO2/PS/mc-Si heterojunction was observed after coating with TiO2. As a consequence, the solar cell efficiencies increased from 1.4% for the uncoated PS/mc-Si structure to 5% for the TiO2 coated one. Impedance spectroscopy confirmed the passivation effect of TiO2 through the improvement of the elaborated cells' electron lifetime and the formation of a TiO2/PS/Au heterojunction with the appearance of a second semi-circle in the Nyquist plot.

  12. Immunotherapy against Metastatic Melanoma with Human iPS Cell-Derived Myeloid Cell Lines Producing Type I Interferons.

    PubMed

    Miyashita, Azusa; Fukushima, Satoshi; Nakahara, Satoshi; Kubo, Yosuke; Tokuzumi, Aki; Yamashita, Junji; Aoi, Jun; Haruta, Miwa; Senju, Satoru; Nishimura, Yasuharu; Jinnin, Masatoshi; Ihn, Hironobu

    2016-03-01

    In recent years, immunotherapy for advanced melanoma has been gaining increased attention. The efficacy of anti-cytotoxic T-lymphocyte antigen 4 antibodies, anti-programmed cell death 1 antibodies, and the BRAF(V600E) kinase inhibitor has been proven in metastatic melanoma. At the same time, adoptive cell transfer has significant effects against metastatic melanoma; however, it is difficult to apply on a broad scale because of the problems related to cell preparation. To overcome these problems, we developed immune cell therapy using induced pluripotent stem (iPS) cells. The benefit of our method is that a large number of cells can be readily obtained. We focused on macrophages for immune cell therapy because macrophage infiltration is frequently observed in solid cancers. In this study, the efficacy of human iPS cell-derived myeloid cell lines (iPS-ML) genetically modified to express type I IFNs against human melanoma cells was examined. The morphology, phagocytic ability, and surface markers of iPS-ML were similar to those of macrophages. The iPS-ML that express type I IFNs (iPS-ML-IFN) showed significant effects in inhibiting the growth of disseminated human melanoma cells in SCID mice. The infiltration of iPS-ML into the tumor nests was confirmed immunohistologically. The iPS-ML-IFNs increased the expression of CD169, a marker of M1 macrophages that can activate antitumor immunity. The iPS-ML-IFNs could infiltrate into tumor tissue and exert anticancer effects in the local tumor tissue. In conclusion, this method will provide a new therapeutic modality for metastatic melanoma. Cancer Immunol Res; 4(3); 248-58. ©2015 AACR. PMID:26714554

  13. The chitinase C gene PsChiC from Pseudomonas sp. and its synergistic effects on larvicidal activity

    PubMed Central

    Zhong, Wanfang; Ding, Shaojun; Guo, Huifang

    2015-01-01

    Pseudomonas sp. strain TXG6-1, a chitinolytic gram-negative bacterium, was isolated from a vegetable field in Taixing city, Jiangsu Province, China. In this study, a Pseudomonas chitinase C gene (PsChiC) was isolated from the chromosomal DNA of this bacterium using a pair of specific primers. The PsChiC gene consisted of an open reading frame of 1443 nucleotides and encoded 480 amino acid residues with a calculated molecular mass of 51.66 kDa. The deduced PsChiC amino acid sequence lacked a signal sequence and consisted of a glycoside hydrolase family 18 catalytic domain responsible for chitinase activity, a fibronectin type III-like domain (FLD) and a C-terminal chitin-binding domain (ChBD). The amino acid sequence of PsChiCshowed high sequence homology (> 95%) with chitinase C from Serratia marcescens. SDS-PAGE showed that the molecular mass of chitinase PsChiC was 52 kDa. Chitinase assays revealed that the chitobiosidase and endochitinase activities of PsChiCwere 51.6- and 84.1-fold higher than those of pET30a, respectively. Although PsChiC showed little insecticidal activity towards Spodoptera litura larvae, an insecticidal assay indicated that PsChiC increased the insecticidal toxicity of SpltNPV by 1.78-fold at 192 h and hastened death. These results suggest that PsChiC from Pseudomonas sp. could be useful in improving the pathogenicity of baculoviruses. PMID:26500441

  14. Psychotropic effects of Lactobacillus plantarum PS128 in early life-stressed and naïve adult mice.

    PubMed

    Liu, Yen-Wenn; Liu, Wei-Hsien; Wu, Chien-Chen; Juan, Yi-Chen; Wu, Yu-Chen; Tsai, Huei-Ping; Wang, Sabrina; Tsai, Ying-Chieh

    2016-01-15

    Ingestion of specific probiotics, namely "psychobiotics", produces psychotropic effects on behavior and affects the hypothalamic-pituitary-adrenal axis and neurochemicals in the brain. We examined the psychotropic effects of a potential psychobiotic bacterium, Lactobacillus plantarum strain PS128 (PS128), on mice subjected to early life stress (ELS) and on naïve adult mice. Behavioral tests revealed that chronic ingestion of PS128 increased the locomotor activities in both ELS and naïve adult mice in the open field test. In the elevated plus maze, PS128 significantly reduced the anxiety-like behaviors in naïve adult mice but not in the ELS mice; whereas the depression-like behaviors were reduced in ELS mice but not in naïve mice in forced swimming test and sucrose preference test. PS128 administration also reduced ELS-induced elevation of serum corticosterone under both basal and stressed states but had no effect on naïve mice. In addition, PS128 reduced inflammatory cytokine levels and increased anti-inflammatory cytokine level in the serum of ELS mice. Furthermore, the dopamine level in the prefrontal cortex (PFC) was significantly increased in PS128 treated ELS and naïve adult mice whereas serotonin (5-HT) level was increased only in the naïve adult mice. These results suggest that chronic ingestion of PS128 could ameliorate anxiety- and depression-like behaviors and modulate neurochemicals related to affective disorders. Thus PS128 shows psychotropic properties and has great potential for improving stress-related symptoms. PMID:26620542

  15. Transcriptome Profiling of the Endophyte Burkholderia phytofirmans PsJN Indicates Sensing of the Plant Environment and Drought Stress

    PubMed Central

    Sheibani-Tezerji, Raheleh; Rattei, Thomas; Sessitsch, Angela; Trognitz, Friederike

    2015-01-01

    ABSTRACT It is widely accepted that bacterial endophytes actively colonize plants, interact with their host, and frequently show beneficial effects on plant growth and health. However, the mechanisms of plant-endophyte communication and bacterial adaption to the plant environment are still poorly understood. Here, whole-transcriptome sequencing of B. phytofirmans PsJN colonizing potato (Solanum tuberosum L.) plants was used to analyze in planta gene activity and the response of strain PsJN to plant stress. The transcriptome of PsJN colonizing in vitro potato plants showed a broad array of functionalities encoded in the genome of strain PsJN. Transcripts upregulated in response to plant drought stress were mainly involved in transcriptional regulation, cellular homeostasis, and the detoxification of reactive oxygen species, indicating an oxidative stress response in PsJN. Genes with modulated expression included genes for extracytoplasmatic function (ECF) group IV sigma factors. These cell surface signaling elements allow bacteria to sense changing environmental conditions and to adjust their metabolism accordingly. TaqMan quantitative PCR (TaqMan-qPCR) was performed to identify ECF sigma factors in PsJN that were activated in response to plant stress. Six ECF sigma factor genes were expressed in PsJN colonizing potato plants. The expression of one ECF sigma factor was upregulated whereas that of another one was downregulated in a plant genotype-specific manner when the plants were stressed. Collectively, our study results indicate that endophytic B. phytofirmans PsJN cells are active inside plants. Moreover, the activity of strain PsJN is affected by plant drought stress; it senses plant stress signals and adjusts its gene expression accordingly. PMID:26350963

  16. Photosensitizer (PS)-cyanine dye (CD) conjugates: Impact of the linkers joining the PS and CD moieties and their orientation in tumor-uptake and photodynamic therapy (PDT).

    PubMed

    James, Nadine S; Joshi, Penny; Ohulchanskyy, Tymish Y; Chen, Yihui; Tabaczynski, Walter; Durrani, Farukh; Shibata, Masayuki; Pandey, Ravindra K

    2016-10-21

    To investigate the impact of linker(s) joining the photosensitizer HPPH [3-(1'-hexyloxy) ethyl-3-devinylpyropheophorbide-a] and the cyanine dye (CD) in tumor-imaging and photodynamic therapy (dual-function agents), a series of HPPH-CD conjugates were synthesized. The modifications were done in an attempt to minimize Forster Resonance Energy Transfer (FRET) between the two chromophores and maximize singlet oxygen production. Among the conjugates containing variable length of linkers, the HPPH-CD conjugate, in which the photosensitizer (PS) and the CD was joined by four Carbon [(CH2)4] units showed higher tumor uptake, improved tumor contrast and limited skin uptake in mice bearing Colon-26 (BALB/c) or U87 tumors in Nude mice. The bi-functional agents in which the HPPH was linked at the meta-position of phenyl-substituted CD 5, 6 and 7 showed longer tumor response (cure) than the corresponding para-substituted analogs 2, 3, and 4, which suggests that the orientation of the PS and CD moieties within the conjugate also makes a substantial difference in tumor-specificity. Compared to HPPH, the singlet oxygen yields of all the HPPH-CD conjugates were significantly low, and required a higher therapeutic dose to achieve the same in vivo response obtained by HPPH-PDT alone. However, conjugate 6 produced a higher singlet oxygen yield with reduced FRET and exhibited enhanced long-term PDT efficacy in mice bearing Colon-26 (BALB/c) and U87 tumors (nude) than its counterparts, including our lead compound (HPPH-CD), making it the most efficacious of the series. Thus, these conjugates bearing cyanine dye moiety (CD) provide an opportunity of imaging deeply seated tumors for fluorescence-guided surgery with an option of PDT. PMID:27543778

  17. Controllable Cooperative Self-Assembly of PS-b-PAA/PS-b-P4VP Mixture by Tuning the Intercorona Interaction.

    PubMed

    Geng, Zhen; Cheng, Zhongkai; Zhu, Yutian; Jiang, Wei

    2016-06-23

    The cooperative self-assembly of amphiphilic polystyrene-block-poly(acrylic acid) (PS144-b-PAA22) and polystyrene-block-poly(4-vinylpyridine) (PS144-b-P4VP33) diblock copolymers in DMF/H2O mixtures has been investigated. Both copolymers self-assemble into small spherical micelles (SSMs) if used individually. However, the equimolar mixture of these two copolymers cooperatively self-assembles into vesicles. It is found that the formation of vesicles is attributed to the complex interactions between PAA and P4VP chains, including the hydrogen bonds between un-ionized acrylic acid units and pyridine units as well as the electronic attractions between ionized acrylic acid units and protonated pyridine units. Since these interactions between PAA and P4VP chains depend on pH value, the cooperatively self-assembled morphology can be easily tuned by the addition of HCl or NaOH. At high addition of H(+) or OH(-), the intercorona interaction is repulsive and the copolymer mixture tends to form SSMs (basic condition) or cylindrical micelles (acidic condition), whereas it prefers to aggregate into vesicles at low addition of H(+) or OH(-) because the intercorona interaction is attractive. Interestingly, the same morphology of the self-assembled aggregates can be obtained either at high H(+) addition or at low OH(-) addition, which results from the nonmonotonic variation of the intercorona interaction along with the addition of HCl or NaOH. The current study implies that it is the intercorona interaction rather than the chemical condition that dominates the cooperatively self-assembled morphology. PMID:27195581

  18. Toughening mechanisms in melt manipulated thermoplastics (PS and PC) and in novel modified epoxies

    NASA Astrophysics Data System (ADS)

    Hydro, Ryan Michael

    This study examined the deformation mechanisms associated with the fatigue and fracture of polystyrene (PS) and polycarbonate (PC) processed using a novel polymer melt manipulation technique, vibration-assisted injection molding (VAIM), as well as the toughening mechanisms of several epoxy resins modified with several novel block co-polymers. VAIM processed PS was found to possess a tensile strength 28% greater than conventionally processed PS, which is in agreement with previous research. The increase in tensile strength is due to the higher craze initiation stress required to overcome the thicker "frozen in" layer of the VAIM processed specimens. Also, the residual orientation present in VAIM specimens appears to retard craze propagation and this is evident by shear banding. Unfortunately, VAIM processed PS did not result in a fatigue lifetime improvement. In fatigue, the PS specimens processed either way usually resulted in the initiation and propagation of a single "killer craze" that caused failure. In contrast, the VAIM processed PC did not exhibit a significant improvement in tensile strength compared against the conventionally molded specimens. In cyclic loading, for the two stress levels examined, both the VAIM and conventional PC specimens were found to perform equally---when examining the average lifetimes and their corresponding standard deviations. In addition, this work studied the deformation mechanisms associated with novel block co-polymer modified epoxies. It was found that the plane strain fracture toughness, KIC, was on the order of 3.0MPa√m for the NanoStrength(TM) E20 modified AEP and PIP cured systems, which is comparable to micro-segregated core-shell particles. Toughness improvements significantly depended on cross-link density of the epoxy matrix, curing agent, and on the amount of polybutadiene present in the toughening agents examined. The system with the highest, KIC, was selected to make a conductive adhesive using 30nm diameter Ag

  19. Dynamic dipole polarizabilities of H{sup −} and Ps{sup −} in weakly coupled plasmas

    SciTech Connect

    Kar, Sabyasachi; Li, H. W.; Jiang, Pinghui

    2013-08-15

    The effects of weakly coupled plasmas on the dynamic dipole polarizabilities of the H{sup −} and Ps{sup −} ions are investigated using highly correlated exponential wave functions. The Debye-Hückel shielding approach of plasma modeling is used to represent weakly coupled plasma environments. In free-atomic cases, results obtained from the present study for H{sup −} are in agreement with the available calculations and results for Ps{sup −} are reported for the first time. Frequency-dependent polarizabilities of H{sup −} and Ps{sup −} as functions of screening parameter are also presented for the first time.

  20. Comparison of 8 × 112 Gb/s PS-QPSK and PDM-QPSK signals over transoceanic distances.

    PubMed

    Nölle, Markus; Fischer, Johannes Karl; Molle, Lutz; Schmidt-Langhorst, Carsten; Peckham, David; Schubert, Colja

    2011-11-21

    We experimentally investigate polarization-switched quadrature phase-shift keying (PS-QPSK) with a symbol rate of 37.3 GBd corresponding to a bit rate of 112 Gb/s. In a wavelength-division multiplexing (WDM) experiment with 50 GHz channel spacing, the transmission performance of PS-QPSK is compared to that of polarization-division multiplexed QPSK (PDM-QPSK) over an EDFA amplified ultra-large-effective-area fiber link. For a bit-error ratio (BER) of 3.8 × 10(-3), the achieved transmission distance is 11000 km for PS-QSPK and 10000 km for PDM-QPSK. PMID:22109464

  1. USGS aerial resolution targets.

    USGS Publications Warehouse

    Salamonowicz, P.H.

    1982-01-01

    It is necessary to measure the achievable resolution of any airborne sensor that is to be used for metric purposes. Laboratory calibration facilities may be inadequate or inappropriate for determining the resolution of non-photographic sensors such as optical-mechanical scanners, television imaging tubes, and linear arrays. However, large target arrays imaged in the field can be used in testing such systems. The USGS has constructed an array of resolution targets in order to permit field testing of a variety of airborne sensing systems. The target array permits any interested organization with an airborne sensing system to accurately determine the operational resolution of its system. -from Author

  2. Late Quaternary environments on the western Lomonosov Ridge (Arctic Ocean) - first results from RV Polarstern expedition PS87 (2014)

    NASA Astrophysics Data System (ADS)

    Spielhagen, Robert F.; Stein, Rüdiger; Mackensen, Andreas; PS87 Shipboard Scientific Party

    2016-04-01

    The interior Arctic Ocean is still one of the least known parts of the earth's surface. In particular this holds true for the deep-sea area north of Greenland which has been reached by research ships only within the last decade. The region is of special interest for climate researchers because numerical climate models predict that under future global warming the shrinking summer sea ice cover will finde a place of refuge here until it totally disappears. In summer 2014 several short and long undisturbed large-volume sediment cores were obtained from the western Lomonosov Ridge between 86.5°N and the North Pole. Here we present first results from site PS87/030 situated at 88°40'N. The combined sedimentary record of a box core and a kasten core analyzed so far is interpreted to represent the environmental variability in the last ca. 200,000 years and can be correlated to comparable records from the eastern Lomonosov Ridge and the Morris Jesup Rise. The well-defined coarse layers with abundant ice-rafted detritus reflect the history of circum-Arctic ice sheets. Planktic foraminifers with a distinct dominance of the polar species were found in most of the analyzed samples and allow to reconstruct the water mass history for this part of the Arctic Ocean. Planktic oxygen and carbon isotope records allow to identify several freshwater events which can be correlated to the decay of ice sheets surrounding the Arctic Ocean. The results presented are, however, preliminary and will be refined by future work including an improved temporal resolution of the records and the addition of further proxy records.

  3. Cellular FLICE-like Inhibitory Protein (c-FLIP) and PS1-associated Protein (PSAP) Mediate Presenilin 1-induced γ-Secretase-dependent and -independent Apoptosis, Respectively.

    PubMed

    Zeng, Linlin; Hu, Chen; Zhang, Fuqiang; Xu, Daniel C; Cui, Mei-Zhen; Xu, Xuemin

    2015-07-24

    Presenilin 1 (PS1) has been implicated in apoptosis; however, its mechanism remains elusive. We report that PS1-induced apoptosis was associated with cellular FLICE-like inhibitory protein (c-FLIP) turnover and that γ-secretase inhibitor blocked c-FLIP turnover and also partially blocked PS1-induced apoptosis. A complete inhibition of PS1-induced apoptosis was achieved by knockdown of PS1-associated protein (PSAP), a mitochondrial proapoptotic protein that forms a complex with Bax upon induction of apoptosis, in the presence of γ-secretase inhibitor. PS1-induced apoptosis was partially inhibited by knockdown of caspase-8, Fas-associated protein with death domain (FADD), or Bid. However, knockdown of Bax or overexpression of Bcl-2 resulted in complete inhibition of PS1-induced apoptosis. These data suggest that PS1 induces apoptosis through two pathways: the γ-secretase-dependent pathway mediated by turnover of c-FLIP and the γ-secretase-independent pathway mediated by PSAP-Bax complex formation. These two pathways converge on Bax to activate mitochondria-dependent apoptosis. These findings provide new insight into the mechanisms by which PS1 is involved in apoptosis and the mechanism by which PS1 exerts its pathogenic effects. In addition, our results suggest that PS2 induces apoptosis through a pathway that is different from that of PS1. PMID:26025363

  4. Cellular FLICE-like Inhibitory Protein (c-FLIP) and PS1-associated Protein (PSAP) Mediate Presenilin 1-induced γ-Secretase-dependent and -independent Apoptosis, Respectively*

    PubMed Central

    Zeng, Linlin; Hu, Chen; Zhang, Fuqiang; Xu, Daniel C.; Cui, Mei-Zhen; Xu, Xuemin

    2015-01-01

    Presenilin 1 (PS1) has been implicated in apoptosis; however, its mechanism remains elusive. We report that PS1-induced apoptosis was associated with cellular FLICE-like inhibitory protein (c-FLIP) turnover and that γ-secretase inhibitor blocked c-FLIP turnover and also partially blocked PS1-induced apoptosis. A complete inhibition of PS1-induced apoptosis was achieved by knockdown of PS1-associated protein (PSAP), a mitochondrial proapoptotic protein that forms a complex with Bax upon induction of apoptosis, in the presence of γ-secretase inhibitor. PS1-induced apoptosis was partially inhibited by knockdown of caspase-8, Fas-associated protein with death domain (FADD), or Bid. However, knockdown of Bax or overexpression of Bcl-2 resulted in complete inhibition of PS1-induced apoptosis. These data suggest that PS1 induces apoptosis through two pathways: the γ-secretase-dependent pathway mediated by turnover of c-FLIP and the γ-secretase-independent pathway mediated by PSAP-Bax complex formation. These two pathways converge on Bax to activate mitochondria-dependent apoptosis. These findings provide new insight into the mechanisms by which PS1 is involved in apoptosis and the mechanism by which PS1 exerts its pathogenic effects. In addition, our results suggest that PS2 induces apoptosis through a pathway that is different from that of PS1. PMID:26025363

  5. Automated conflict resolution issues

    NASA Technical Reports Server (NTRS)

    Wike, Jeffrey S.

    1991-01-01

    A discussion is presented of how conflicts for Space Network resources should be resolved in the ATDRSS era. The following topics are presented: a description of how resource conflicts are currently resolved; a description of issues associated with automated conflict resolution; present conflict resolution strategies; and topics for further discussion.

  6. Conflict Resolution Bibliography.

    ERIC Educational Resources Information Center

    Charnofsky, Norene M., Comp.

    Various theories and approaches to conflict resolution and peace education are presented in the 31 resources listed in this annotated bibliography. It is divided into two sections. Section 1 contains materials designed to help adults become more effective role models for the peaceful resolution of conflict. Topics include parent/child conflicts,…

  7. Effects of spatial resolution

    NASA Technical Reports Server (NTRS)

    Abrams, M.

    1982-01-01

    Studies of the effects of spatial resolution on extraction of geologic information are woefully lacking but spatial resolution effects can be examined as they influence two general categories: detection of spatial features per se; and the effects of IFOV on the definition of spectral signatures and on general mapping abilities.

  8. Generation of intense 10-ps, 193-nm pulses using simple distributed feedback dye lasers and an ArF(*) amplifier.

    PubMed

    Hatten, D L; Cui, Y; Iii, W T; Mikes, T; Goldhar, J

    1992-11-20

    A pair of holographic distributed feedback dye lasers is used to generate 10-ps pulses at two selected wavelengths that are mixed in a BBO crystal to produce a pulse ~ 10 ps in duration at 193 nm. This seed pulse is subsequently amplified in an ArF(*) excimer laser to an energy of 10-15 mJ with <40 microJ in amplified spontaneous emission. The pulses are nearly transform limited and diffraction limited. PMID:20802565

  9. The PS1 Hairpin of Mcm3 Is Essential for Viability and for DNA Unwinding In Vitro

    PubMed Central

    Lam, Simon K. W.; Ma, Xiaoli; Sing, Tina L.; Shilton, Brian H.; Brandl, Christopher J.; Davey, Megan J.

    2013-01-01

    The pre-sensor 1 (PS1) hairpin is found in ring-shaped helicases of the AAA+ family (ATPases associated with a variety of cellular activities) of proteins and is implicated in DNA translocation during DNA unwinding of archaeal mini-chromosome maintenance (MCM) and superfamily 3 viral replicative helicases. To determine whether the PS1 hairpin is required for the function of the eukaryotic replicative helicase, Mcm2-7 (also comprised of AAA+ proteins), we mutated the conserved lysine residue in the putative PS1 hairpin motif in each of the Saccharomyces cerevisiae Mcm2-7 subunits to alanine. Interestingly, only the PS1 hairpin of Mcm3 was essential for viability. While mutation of the PS1 hairpin in the remaining MCM subunits resulted in minimal phenotypes, with the exception of Mcm7 which showed slow growth under all conditions examined, the viable alleles were synthetic lethal with each other. Reconstituted Mcm2-7 containing Mcm3 with the PS1 mutation (Mcm3K499A) had severely decreased helicase activity. The lack of helicase activity provides a probable explanation for the inviability of the mcm3K499A strain. The ATPase activity of Mcm2-73K499A was similar to the wild type complex, but its interaction with single-stranded DNA in an electrophoretic mobility shift assay and its associations in cells were subtly altered. Together, these findings indicate that the PS1 hairpins in the Mcm2-7 subunits have important and distinct functions, most evident by the essential nature of the Mcm3 PS1 hairpin in DNA unwinding. PMID:24349215

  10. Non-viral generation of marmoset monkey iPS cells by a six-factor-in-one-vector approach.

    PubMed

    Debowski, Katharina; Warthemann, Rita; Lentes, Jana; Salinas-Riester, Gabriela; Dressel, Ralf; Langenstroth, Daniel; Gromoll, Jörg; Sasaki, Erika; Behr, Rüdiger

    2015-01-01

    Groundbreaking studies showed that differentiated somatic cells of mouse and human origin could be reverted to a stable pluripotent state by the ectopic expression of only four proteins. The resulting pluripotent cells, called induced pluripotent stem (iPS) cells, could be an alternative to embryonic stem cells, which are under continuous ethical debate. Hence, iPS cell-derived functional cells such as neurons may become the key for an effective treatment of currently incurable degenerative diseases. However, besides the requirement of efficacy testing of the therapy also its long-term safety needs to be carefully evaluated in settings mirroring the clinical situation in an optimal way. In this context, we chose the long-lived common marmoset monkey (Callithrix jacchus) as a non-human primate species to generate iPS cells. The marmoset monkey is frequently used in biomedical research and is gaining more and more preclinical relevance due to the increasing number of disease models. Here, we describe, to our knowledge, the first-time generation of marmoset monkey iPS cells from postnatal skin fibroblasts by non-viral means. We used the transposon-based, fully reversible piggyback system. We cloned the marmoset monkey reprogramming factors and established robust and reproducible reprogramming protocols with a six-factor-in-one-construct approach. We generated six individual iPS cell lines and characterized them in comparison with marmoset monkey embryonic stem cells. The generated iPS cells are morphologically indistinguishable from marmoset ES cells. The iPS cells are fully reprogrammed as demonstrated by differentiation assays, pluripotency marker expression and transcriptome analysis. They are stable for numerous passages (more than 80) and exhibit euploidy. In summary, we have established efficient non-viral reprogramming protocols for the derivation of stable marmoset monkey iPS cells, which can be used to develop and test cell replacement therapies in

  11. Spatio-temporal Responses of Arabidopsis Leaves in Photosynthetic Performance and Metabolite Contents to Burkholderia phytofirmans PsJN.

    PubMed

    Su, Fan; Gilard, Françoise; Guérard, Florence; Citerne, Sylvie; Clément, Christophe; Vaillant-Gaveau, Nathalie; Dhondt-Cordelier, Sandrine

    2016-01-01

    A valuable strategy to improve crop yield consists in the use of plant growth-promoting rhizobacteria (PGPRs). However, the influence of PGPR colonization on plant physiology is largely unknown. PGPR Burkholderia phytofirmans strain PsJN (Bp PsJN) colonized only Arabidopsis thaliana roots after seed or soil inoculation. Foliar bacteria were detected only after leaf infiltration. Since, different bacterial times of presence and/or locations in host plant could lead to different plant physiological responses, photosynthesis, and metabolite profiles in A. thaliana leaves were thus investigated following leaf, root, or seed inoculation with Bp PsJN. Only Bp PsJN leaf colonization transiently decreased cyclic electron transport and effective quantum yield of photosystem I (PSI), and prevented a decrease in net photosynthesis and stomatal opening compared to the corresponding control. Metabolomic analysis revealed that soluble sugars, amino acids or their derivatives accumulated differently in all Bp PsJN-inoculated plants. Octanoic acid accumulated only in case of inoculated plants. Modifications in vitamin, organic acid such as tricarboxylic acid intermediates, and hormone amounts were dependent on bacterial time of presence and location. Additionally, a larger array of amino acids and hormones (auxin, cytokinin, abscisic acid) were modified by seed inoculation with Bp PsJN. Our work thereby provides evidence that relative short-term inoculation with Bp PsJN altered physiological status of A. thaliana leaves, whereas long-term bacterization triggered modifications on a larger set of metabolites. Our data highlighted the changes displayed during this plant-microbe interaction to trigger physiological and metabolic responses that could explain the increase in plant growth or stress tolerance conferred by the presence of Bp PsJN. PMID:27066045

  12. SALT spectroscopic classification of PS15cjr (=LSQ15bgf) as a type-IIb supernova near maximum light

    NASA Astrophysics Data System (ADS)

    Jha, S. W.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Smith, K. W.; Wright, D.; Smartt, S. J.; Huber, M.; Chambers, K. C.; Flewelling, H.; Willman, M.; Primak, N.; Schultz, A.; Gibson, B.; Magnier, E.; Waters, C.; Tonry, J.; Wainscoat, R. J.; Kniazev, A.

    2015-10-01

    We obtained SALT (+RSS) spectroscopy of PS15cjr (=LSQ15bgf) on 2015 Oct 16.9 UT, covering the wavelength range 350-950 nm. Cross-correlation of the spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows PS15cjr is likely a type-IIb a few days past maximum light, with a good match to the spectrum of SN 1993J at +4 days.

  13. SALT spectroscopic classification of PS16efm (= SN 2016fxu) as a type-Ic supernova after maximum light

    NASA Astrophysics Data System (ADS)

    Jha, S. W.; Dettman, K.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Kotze, M.

    2016-09-01

    We obtained SALT (+RSS) spectroscopy of PS16efm (= SN 2016fxu) on 2016 Sep 8.0 UT, covering the wavelength range 350-920 nm. Cross-correlation of the spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows PS16efm is a type-Ic supernova approximately two to three weeks past maximum light.

  14. Altered life cycle in Arabidopsis plants expressing PsUGT1, a UDP-glucuronosyltransferase-encoding gene from pea.

    PubMed

    Woo, Ho-Hyung; Faull, Kym F; Hirsch, Ann M; Hawes, Martha C

    2003-10-01

    Alfalfa (Medicago sativa) and Arabidopsis were used as model systems to examine molecular mechanisms underlying developmental effects of a microsomal UDP-glucuronosyltransferase-encoding gene from pea (Pisum sativum; PsUGT1). Alfalfa expressing PsUGT1 antisense mRNA under the control of the cauliflower mosaic virus (CaMV) 35S promoter exhibited delayed root emergence, reduced root growth, and increased lateral root development. The timing of root emergence in wild-type and antisense plants was correlated with the transient accumulation of auxin at the site of root emergence. Cell suspension cultures derived from the antisense alfalfa plants exhibited a delay in cell cycle from 24-h in the wild-type plants to 48-h in the antisense plants. PsUGT1::uidA was introduced into Arabidopsis to demonstrate that, as in alfalfa and pea, PsUGT1 expression occurs in regions of active cell division. This includes the root cap and root apical meristems, leaf primordia, tips of older leaves, and the transition zone between the hypocotyl and the root. Expression of PsUGT1::uidA colocalized with the expression of the auxin-responding reporter DR5::uidA. Co-expression of DR5::uidA in transgenic Arabidopsis lines expressing CaMV35S::PsUGT1 revealed that ectopic expression of CaMV35S::PsUGT1 is correlated with a change in endogenous auxin gradients in roots. Roots of ecotype Columbia expressing CaMV35S::PsUGT1 exhibited distinctive responses to exogenous naphthalene acetic acid. Completion of the life cycle occurred in 4 to 6 weeks compared with 6 to 7 weeks for wild-type Columbia. Inhibition of endogenous ethylene did not correct this early senescence phenotype. PMID:12972656

  15. Spatio-temporal Responses of Arabidopsis Leaves in Photosynthetic Performance and Metabolite Contents to Burkholderia phytofirmans PsJN

    PubMed Central

    Su, Fan; Gilard, Françoise; Guérard, Florence; Citerne, Sylvie; Clément, Christophe; Vaillant-Gaveau, Nathalie; Dhondt-Cordelier, Sandrine

    2016-01-01

    A valuable strategy to improve crop yield consists in the use of plant growth-promoting rhizobacteria (PGPRs). However, the influence of PGPR colonization on plant physiology is largely unknown. PGPR Burkholderia phytofirmans strain PsJN (Bp PsJN) colonized only Arabidopsis thaliana roots after seed or soil inoculation. Foliar bacteria were detected only after leaf infiltration. Since, different bacterial times of presence and/or locations in host plant could lead to different plant physiological responses, photosynthesis, and metabolite profiles in A. thaliana leaves were thus investigated following leaf, root, or seed inoculation with Bp PsJN. Only Bp PsJN leaf colonization transiently decreased cyclic electron transport and effective quantum yield of photosystem I (PSI), and prevented a decrease in net photosynthesis and stomatal opening compared to the corresponding control. Metabolomic analysis revealed that soluble sugars, amino acids or their derivatives accumulated differently in all Bp PsJN-inoculated plants. Octanoic acid accumulated only in case of inoculated plants. Modifications in vitamin, organic acid such as tricarboxylic acid intermediates, and hormone amounts were dependent on bacterial time of presence and location. Additionally, a larger array of amino acids and hormones (auxin, cytokinin, abscisic acid) were modified by seed inoculation with Bp PsJN. Our work thereby provides evidence that relative short-term inoculation with Bp PsJN altered physiological status of A. thaliana leaves, whereas long-term bacterization triggered modifications on a larger set of metabolites. Our data highlighted the changes displayed during this plant–microbe interaction to trigger physiological and metabolic responses that could explain the increase in plant growth or stress tolerance conferred by the presence of Bp PsJN. PMID:27066045

  16. High-resolution dynamic speech imaging with deformation estimation.

    PubMed

    Maojing Fu; Barlaz, Marissa S; Shosted, Ryan K; Zhi-Pei Liang; Sutton, Bradley P

    2015-08-01

    Dynamic speech magnetic resonance imaging (DSMRI) is a promising technique for visualizing articulatory motion in real time. However, many existing applications of DSMRI have been limited by slow imaging speed and the lack of quantitative motion analysis. In this paper, we present a novel DS-MRI technique to simultaneously estimate dynamic image sequence of speech and the associated deformation field. Extending on our previous Partial Separability (PS) model-based methods, the proposed technique visualizes both speech motion and deformation with a spatial resolution of 2.2 × 2.2 mm(2) and a nominal frame rate of 100 fps. Also, the technique enables direct analysis of articulatory motion through the deformation fields. Effectiveness of the method is systematically examined via in vivo experiments. Utilizing the obtained high-resolution images and deformation fields, we also performed a phonetics study on Brazilian Portuguese to show the method's practical utility. PMID:26736572

  17. Negative velocity gradients in the western US upper mantle from Ps and Sp receiver functions

    NASA Astrophysics Data System (ADS)

    McClenahan, Joseph J.

    Using three-component broad-band seismic data from EarthScope Transportable Array, PASSCAL arrays, and other regional seismic deployments in the United States west of Georgia, receiver functions are created using a multi-channel deconvolution algorithm, yielding 65,519 Ps and 34,057 Sp receiver functions. An automated depth picker was coded to pick depths and amplitudes of arrivals from a common conversion point image volume. The depth picker finds a pervasive negative velocity gradient (NVG) between the Moho and 150 km depth. The resulting NVG depth maps find depth ranges of 63 - 120 km (Ps) and 64 - 135 km (Sp). Using a surface wave shear velocity model (Shen and Ritzwoller, 2012) and an anelastic olivine model (Jackson and Faul, 2010), a temperature volume was created to assess temperatures at the NVG depths. The NVG is shown to exist across a broad temperature spectrum (Ps, 602° - 1356° C; Sp, 620° - 1398° C), with Ps modal peaks at 811° C and 1231° C, and Sp modal peaks at 732° C and 1273° C. These modal peaks correspond with two modal NVG Ps/Sp depths; 86 km (811° C) and 70 km (1231° C) for Ps, 97 km (732° C) and 82 km (1273° C) for Sp. From the NVG depths and temperatures, as well as lithospheric age, geologic history, and xenolith constraints, three species of NVG are identified. East of the Rocky Mountain Front, NVG depths are deep (82 - 135 km), with cold mantle temperatures (<950° C), and these NVG arrivals are internal to the lithosphere. This NVG species is interpreted as a metasomatic freezing front from accumulation of volatile rich low velocity phase melts (phlogopite, amphibole) over Ga time scales. West of the Precambrian rift hinge line to the Pacific, and in the Rio Grand Rift area, NVG depths are shallow (63 - 101 km) and mantle temperatures are warm (>1150° C). This NVG is at super-solidus conditions, thus melt is believed to cause this warm, shallow NVG species. Finally, in the Colorado Rocky Mountain and Colorado Plateau

  18. Generation and validation of PAX7 reporter lines from human iPS cells using CRISPR/Cas9 technology.

    PubMed

    Wu, Jianbo; Hunt, Samuel D; Xue, Haipeng; Liu, Ying; Darabi, Radbod

    2016-03-01

    Directed differentiation of iPS cells toward various tissue progenitors has been the focus of recent research. Therefore, generation of tissue-specific reporter iPS cell lines provides better understanding of developmental stages in iPS cells. This technical report describes an efficient strategy for generation and validation of knock-in reporter lines in human iPS cells using the Cas9-nickase system. Here, we have generated a knock-in human iPS cell line for the early myogenic lineage specification gene of PAX7. By introduction of site-specific double-stranded breaks (DSB) in the genomic locus of PAX7 using CRISPR/Cas9 nickase pairs, a 2A-GFP reporter with selection markers has been incorporated before the stop codon of the PAX7 gene at the last exon. After positive and negative selection, single cell-derived human iPS clones have been isolated and sequenced for in-frame positioning of the reporter construct. Finally, by using a nuclease-dead Cas9 activator (dCas9-VP160) system, the promoter region of PAX7 has been targeted for transient gene induction to validate the GFP reporter activity. This was confirmed by flow cytometry analysis and immunostaining for PAX7 and GFP. This technical report provides a practical guideline for generation and validation of knock-in reporters using CRISPR/Cas9 system. PMID:26826926

  19. Overexpression of Notch3 and pS6 Is Associated with Poor Prognosis in Human Ovarian Epithelial Cancer

    PubMed Central

    Yun, Rongna; Yu, Xiaolin; Huang, Genhua; Tan, Buzhen

    2016-01-01

    Notch3 and pS6 play important roles in tumor angiogenesis. To assess the expression of Notch3 and pS6 in Chinese ovarian epithelial cancer patients, a ten-year follow-up study was performed in ovarian epithelial cancer tissues from 120 specimens of human ovarian epithelial cancer, 30 specimens from benign ovarian tumors, and 30 samples from healthy ovaries by immunohistochemistry. The results indicate that the expression of Notch3 and pS6 was higher in ovarian epithelial cancer than in normal ovary tissues and in benign ovarian tumor tissues (p < 0.01). In tumor tissues, Notch3 expression and pS6 expression were negatively associated with age (p > 0.05) but positively associated with clinical stage, pathological grading, histologic type, lymph node metastasis, and ascites (p < 0.05 or p < 0.01). A follow-up survey of 64 patients with ovarian epithelial cancer showed that patients with high Notch3 and pS6 expression had a shorter survival time (p < 0.01), in which the clinical stage (p < 0.05) and Notch3 expression (p < 0.01) played important roles. In conclusion, Notch3 and pS6 are significantly related to ovarian epithelial cancer development and prognosis, and their combination represents a potential biomarker and therapeutic target in ovarian tumor angiogenesis. PMID:27445438

  20. [Induced pluripotent stem (iPS) cell-based cell therapy for muscular dystrophy: current progress and future prospects].

    PubMed

    Nishiyama, Takashi; Takeda, Shin'ichi

    2012-01-01

    Duchenne muscular dystrophy (DMD) is a devastating muscle disorder caused by mutations in the dystrophin gene. There is currently no effective treatment for DMD. Muscle satellite cells are tissue-specific stem cells found in the skeletal muscle; these cells play a central role in postnatal muscle growth and regeneration, and are, therefore, a potential source for stem cell therapy for DMD. However, transplantation of satellite cell-derived myoblasts has not yet been successful in humans. Patient-specific induced pluripotent stem (iPS) cells are expected to be a source for autologous cell transplantation therapy for DMD, because iPS cells can proliferate vigorously in vitro and can differentiate into multiple cell lineages both in vitro and in vivo. Here, we discuss the strategies to generate muscle stem cells from iPS cells. So far, the most promising method for generating muscle stem cells from iPS cells is the conditional overexpression of Pax3 or Pax7 in the differentiating mouse embryoid bodies. However, induction methods for human iPS cells have not yet been developed. Thus, iPS cells are expected to serve as an in vitro disease model system, which will enable us to determine the pathology of muscle diseases and develop pharmaceutical treatments. PMID:22223500

  1. Early growth promotion and leaf level physiology changes in Burkholderia phytofirmans strain PsJN inoculated switchgrass.

    PubMed

    Wang, Bingxue; Mei, Chuansheng; Seiler, John R

    2015-01-01

    Switchgrass (SG) is one of the most promising next generation biofuel crops in North America. Inoculation with bacterial endophytes has improved growth of several plant species. Our study demonstrated that Burkholderia phytofirmans strain PsJN, a well-studied plant growth promoting rhizo-bacterium (PGPR) significantly increased both aboveground and belowground biomass (DW) and promoted elongation of root, stem and leaf within 17 days following inoculation. Furthermore, the enhanced root growth in PsJN inoculated plants lagged behind the shoot response, resulting in greater allocation to aboveground growth (p = 0.0041). Lower specific root length (SRL, p = 0.0158) and higher specific leaf weight (SLW, p = 0.0029) were also observed in PsJN inoculated seedlings, indicating changes in development. Photosynthetic rates (Ps) were also significantly higher in PsJN inoculated seedlings after 17 days (54%, p = 0.0016), and this occurred initially without increases in stomatal conductance resulting in significantly greater water use efficiency (WUE, 37.7%, p = 0.0467) and lower non-stomatal limitation (LNS, 29.6%, p = 0.0222). These rapid changes in leaf level physiology are at least partially responsible for the growth enhancement due to PsJN. PMID:25461696

  2. Insights into tidal disruption of stars from PS1-10jh

    NASA Astrophysics Data System (ADS)

    Strubbe, Linda E.; Murray, Norman

    2015-12-01

    Was PS1-10jh, an optical/ultraviolet transient discovered by the Pan-STARRS Medium Deep Survey, the tidal disruption of a star by a massive black hole (BH)? We address two aspects of the problem: the composition of the putative disrupted object (using the spectroscopic data), and the energetics of the observed gas and radiation (using the photometric data). We perform photoionization calculations and compare with the observed lower limit of the line ratio L_{He II 4686}/L_{Hα }>5 to argue that this event was not the disruption of a solar-type star, and instead was likely the disruption of a helium core (as first proposed by Gezari et al.). Disruption of such a dense object requires a relatively small central BH, MBH ≲ 2 × 105 M⊙. We use the photometric data to infer that PS1-10jh comprised an outflow of ˜0.01 M⊙ of gas, escaping from the BH at ˜1000 km s-1, and we propose that this outflow was driven primarily by radiation pressure trapped by Thomson and resonance line scattering. The large ratio of radiated energy to kinetic energy, Erad/EK ˜ 104, together with the large value of Erad ˜ 2 × 1051 erg, suggests that the outflow was shocked at large radius (perhaps similar to superluminous supernovae or the internal shock model for gamma-ray bursts). We describe puzzles in the physics of PS1-10jh, and discuss how this event may help us understand future tidal disruptions and super-Eddington accretion events as well.

  3. Characterization of dye-doped PMMA, CA, and PS films as recording materials

    NASA Astrophysics Data System (ADS)

    Lessard, Roger A.; Tork, Amir; Lafond, Christophe; Bolte, Michel; Ritcey, Anna-Marie R.

    2000-05-01

    The photoinduced reversible color change and in-situ recording of fulgide Aberchrome 670 doped polymethyl methacrylate (PMMA), cellulose acetate (CA) and polystyrene (PS) were investigated. Upon UV and visible exposure, closed-form absorbency followed first-order kinetic. The rate constants KUV and KVIS for respectively the coloring and bleaching process were determined. In PMMA matrix KUV equals 1.2 * 10-3 s-1 and KVIS equals 11.1 8 10-3 s-1, in CA matrix kUV equals 2.7 * 10-3 s-1 and kVIS equals 6.4 8 10-3 s-1 and in the case of PS film kUV equals 2.1 * 10-3 s-1 and kVIS equals 11.9 * 10-3 s-1 were obtained. These results show that, KVIS is much larger than KUV for all matrices. Photochemical fatigue resistance in different polymer matrices was investigated. We found a loss of 9, 11 and 13 percent in PS, CA and PMMA respectively, after 10 repeated UV and visible cycles. The real time holographic recording in fulgide doped PMMA films were studied. We have analyzed the effect of the photochromic concentration, the thickness of the film and the recording intensity on the diffraction efficiency. The highest diffraction efficiency is obtained for the concentration of 5 percent of the fulgide dye in PMMA film with an exposure energy of 10 mw/cm2. For the same sample we have not observed any diffraction beam when the sample was illuminated by an intensity of 3 mw/cm2.

  4. LCAT deficiency does not impair amyloid metabolism in APP/PS1 mice[S

    PubMed Central

    Stukas, Sophie; Freeman, Lita; Lee, Michael; Wilkinson, Anna; Ossoli, Alice; Vaisman, Boris; Demosky, Stephen; Chan, Jeniffer; Hirsch-Reinshagen, Veronica; Remaley, Alan T.; Wellington, Cheryl L.

    2014-01-01

    A key step in plasma HDL maturation from discoidal to spherical particles is the esterification of cholesterol to cholesteryl ester, which is catalyzed by LCAT. HDL-like lipoproteins in cerebrospinal fluid (CSF) are also spherical, whereas nascent lipoprotein particles secreted from astrocytes are discoidal, suggesting that LCAT may play a similar role in the CNS. In plasma, apoA-I is the main LCAT activator, while in the CNS, it is believed to be apoE. apoE is directly involved in the pathological progression of Alzheimer’s disease, including facilitating β-amyloid (Aβ) clearance from the brain, a function that requires its lipidation by ABCA1. However, whether apoE particle maturation by LCAT is also required for Aβ clearance is unknown. Here we characterized the impact of LCAT deficiency on CNS lipoprotein metabolism and amyloid pathology. Deletion of LCAT from APP/PS1 mice resulted in a pronounced decrease of apoA-I in plasma that was paralleled by decreased apoA-I levels in CSF and brain tissue, whereas apoE levels were unaffected. Furthermore, LCAT deficiency did not increase Aβ or amyloid in APP/PS1 LCAT−/− mice. Finally, LCAT expression and plasma activity were unaffected by age or the onset of Alzheimer’s-like pathology in APP/PS1 mice. Taken together, these results suggest that apoE-containing discoidal HDLs do not require LCAT-dependent maturation to mediate efficient Aβ clearance. PMID:24950691

  5. 200 ps FWHM and 100 MHz repetition rate ultrafast gated camera for optical medical functional imaging

    NASA Astrophysics Data System (ADS)

    Uhring, Wilfried; Poulet, Patrick; Hanselmann, Walter; Glazenborg, René; Zint, Virginie; Nouizi, Farouk; Dubois, Benoit; Hirschi, Werner

    2012-04-01

    The paper describes the realization of a complete optical imaging device to clinical applications like brain functional imaging by time-resolved, spectroscopic diffuse optical tomography. The entire instrument is assembled in a unique setup that includes a light source, an ultrafast time-gated intensified camera and all the electronic control units. The light source is composed of four near infrared laser diodes driven by a nanosecond electrical pulse generator working in a sequential mode at a repetition rate of 100 MHz. The resulting light pulses, at four wavelengths, are less than 80 ps FWHM. They are injected in a four-furcated optical fiber ended with a frontal light distributor to obtain a uniform illumination spot directed towards the head of the patient. Photons back-scattered by the subject are detected by the intensified CCD camera; there are resolved according to their time of flight inside the head. The very core of the intensified camera system is the image intensifier tube and its associated electrical pulse generator. The ultrafast generator produces 50 V pulses, at a repetition rate of 100 MHz and a width corresponding to the 200 ps requested gate. The photocathode and the Micro-Channel-Plate of the intensifier have been specially designed to enhance the electromagnetic wave propagation and reduce the power loss and heat that are prejudicial to the quality of the image. The whole instrumentation system is controlled by an FPGA based module. The timing of the light pulses and the photocathode gating is precisely adjustable with a step of 9 ps. All the acquisition parameters are configurable via software through an USB plug and the image data are transferred to a PC via an Ethernet link. The compactness of the device makes it a perfect device for bedside clinical applications.

  6. Engineering a perfusable 3D human liver platform from iPS cells.

    PubMed

    Schepers, Arnout; Li, Cheri; Chhabra, Arnav; Seney, Benjamin Tschudy; Bhatia, Sangeeta

    2016-07-01

    In vitro models of human tissue are crucial to our ability to study human disease as well as develop safe and effective drug therapies. Models of single organs in static and microfluidic culture have been established and shown utility for modeling some aspects of health and disease; however, these systems lack multi-organ interactions that are critical to some aspects of drug metabolism and toxicity. Thus, as part of a consortium of researchers, we have developed a liver chip that meets the following criteria: (1) employs human iPS cells from a patient of interest, (2) cultures cells in perfusable 3D organoids, and (3) is robust to variations in perfusion rate so as to be compatible in series with other specialized tissue chips (e.g. heart, lung). In order to achieve this, we describe methods to form hepatocyte aggregates from primary and iPS-derived cells, alone and in co-culture with support cells. This necessitated a novel culture protocol for the interrupted differentiation of iPS cells that permits their removal from a plated surface and aggregation while maintaining phenotypic hepatic functions. In order to incorporate these 3D aggregates in a perfusable platform, we next encapsulated the cells in a PEG hydrogel to prevent aggregation and overgrowth once on chip. We adapted a C-trap chip architecture from the literature that enabled robust loading with encapsulated organoids and culture over a range of flow rates. Finally, we characterize the liver functions of this iHep organoid chip under perfusion and demonstrate a lifetime of at least 28 days. We envision that such this strategy can be generalized to other microfluidic tissue models and provides an opportunity to query patient-specific liver responses in vitro. PMID:27296616

  7. Recent advance in Asian polar science - Commemorating ten-year activities of the Asian Forum for Polar Sciences (AFoPS)

    NASA Astrophysics Data System (ADS)

    Watanabe, Kentaro; Doi, Koichiro; Ewe, Hong Tat; Krishnan, Kottekkatu Padinchati; Lee, Jae Il; Liu, Ruiyuan

    2015-12-01

    The Asian Forum for Polar Sciences (AFoPS) was established in 2004 to encourage and facilitate cooperation for the advance of polar sciences among countries in the Asian region. It commemorated tenth anniversary organizing the AFoPS Symposium on 7 October, 2014 in Port Dickson, Malaysia, hosted by the National Antarctic Research Center (NARC), University of Malaya. This second volume of AFoPS Special Issue includes those presentations submitted to the Symposium and scientific papers from AFoPS countries on wide variety of polar research. This publication is one of the excellent achievements of AFoPS.

  8. Polarimetry diagnostic on OMEGA EP using a 10-ps, 263-nm probe beam

    SciTech Connect

    Davies, A. Haberberger, D.; Boni, R.; Ivancic, S.; Brown, R.; Froula, D. H.

    2014-11-15

    A polarimetry diagnostic was built and characterized for magnetic-field measurements in laser-plasma experiments on the OMEGA EP laser. This diagnostic was built into the existing 4ω (263-nm) probe system that employs a 10-ps laser pulse collected with an f/4 imaging system. The diagnostic measures the rotation of the probe beam's polarization. The polarimeter uses a Wollaston prism to split the probe beam into orthogonal polarization components. Spatially localized intensity variations between images indicate polarization rotation. Magnetic fields can be calculated by combining the polarimetry data with the measured plasma density profile obtained from angular filter refractometry.

  9. Ps receiver function imaging of crustal structure and Moho topography beneath the Northeast Caribbean

    NASA Astrophysics Data System (ADS)

    Ntuli, G.; Agrawal, M.; Pulliam, J.; Huerfano Moreno, V. A.; Polanco Rivera, E.

    2015-12-01

    Due to its tectonic history, the Caribbean plate contains complex fault systems that are likely to have disrupted the Moho. To study the region's subsurface structure we computed a 3D image of the Northeast Caribbean via "velocity analysis" with Ps receiver functions. In this technique we simultaneously find, via an optimization procedure, depths to major discontinuities (in this case the Moho) and P and S velocity profiles beneath each seismic station. Ps receiver functions are time series computed from three-component seismograms that identify waves converted from P- to S-type at velocity discontinuities, such as the Moho and subducting lithosphere. Data were requested from the IRIS Data Management Center for events that occurred in the 2005-15 time period with magnitudes of 5.5-8.0 and epicentral distances of 30°-95° from stations in the study region. Data pre-processing steps include tapering, removing the trend and mean, and rotating from Z-N-E to L-Q-T (ray-based) coordinate systems. Ps receiver functions were then computed via iterative deconvolution in the time domain and the best receiver functions were stacked and modeled to generate a 3D image of the subsurface. Shear velocity profiles for each station are varied in a procedure, driven by simulated annealing, that seeks to optimize the correlation of a target feature—in this case the Moho—in the set of pre-processed Ps receiver functions. This procedure is feasible only when station spacing is relatively dense, which limits its success in this region to the islands of Puerto Rico and Hispaniola. Individual receiver functions were computed for isolated stations in the NE Caribbean, as well, but velocity analysis is limited to the two islands that have the densest station coverage. Moho depths beneath Puerto Rico range from 24 km, in the north, to 37 km, in the south. Moho depths beneath Hispaniola range from 23 km to 36 km but exhibit a more complex pattern of variation than beneath Puerto Rico

  10. A study of ps-laser-induced-damage-threshold in hybrid metal-dielectric mirrors

    NASA Astrophysics Data System (ADS)

    Škoda, Václav; Vanda, Jan

    2014-10-01

    Laser-induced-damage-threshold of two types of metal-dielectric mirrors was tested using a laser apparatus working at 800 nm wavelength with 1 ps pulse length at 1 kHz repetition rate and in 106-on-1 test mode. Four sets of mirror samples with different layer system designs using a multilayer Ta2O5/SiO2 coating on silver or gold metal layer were manufactured. Both BK7 and fused silica substrate materials were used for manufacturing of samples. The measured damage thresholds at 45 deg incidence and P-polarization were compared with computed properties of layer system and used materials.

  11. PS300 Tribomaterials Evaluated at 6500C by Bushing Test Rig

    NASA Technical Reports Server (NTRS)

    Striebing, Donald R.; DellaCorte, Christopher

    2004-01-01

    A new facility has been developed to test the tribological behavior (friction and wear) of PS300 solid lubricant bushings at high temperatures. PS300 is a commercially available solid lubricant invented at the NASA Glenn Research Center. It can be prepared as a plasma spray coating or as a free-standing powder metallurgy component, designated PM300. PS300 and PM300 composites are designed to lubricate sliding components at temperatures above the capability of today's best oils, greases, and solid lubricants. One of the primary applications being pursued for PM300 is the development of bushings for use in high-temperature machinery. Examples include inlet guide vane bushings for gas turbines and conveyors, and bearings for industrial furnaces and ovens. Encouraging preliminary field trials indicate that PS300 and PM300 lubricant materials have been commercialized successfully in several industrial applications. However, the lack of laboratory performance data has hindered further commercialization especially for new applications that differ significantly from the established experience base. The purpose of the newly developed bushing test rig will be to determine the performance characteristics of PM300, and other materials, under conditions closely matching intended applications. The data will be used to determine engineering friction and wear rates and to estimate the life expectancy of bushings for new applications. In the new rig, the bushing is loaded against a rotating shaft inside a furnace enclosure (see the preceding photograph). Loads can vary from 5 to 200 N, speeds from 1 to 400 rpm, and temperatures from 25 to 800 C. Furnace temperature, bushing temperature, shaft speed, and torque are monitored during the test, and wear of both the bushing and the shaft is measured after testing is completed. Initially, PM300 bushings will be evaluated and compared with lower temperature, traditional bushing materials like graphite and porous bronze. The baseline PM304

  12. Pattern formation and phase behavior in PS-B-Si containing block copolymer thin film

    NASA Astrophysics Data System (ADS)

    Hsieh, I.-Fan

    Since the top-down approaches, such as the extremely ultraviolet (EUV) technique and the high-index fluid-based immersion ArF lithography, may be cover one or two generations, these lithography technologies are getting more severe for the feature size scaling down to sub 10 nm. The directed self-assembly technology of block copolymers is one of the candidates for next generation lithography which can afford feature sizes that are dictated by the molecular weight of the block copolymer and are typically 15 to 30 nm. Directed self-assembly of block copolymers has attracted attention as a technology to extend photoresist-based lithography to smaller dimensions. It has been demonstrated that the directed self assembly of block copolymer offers a new route to perfect nanolithographic pattering at sub-50 nm length scale with molecular scale precision. For application in electronic media, it requires large-area, long-range ordered structures, which is both a kinetic and thermodynamic problem and requires subtle balance of various parameters and processing conditions. So far, block copolymer thin films have already achieved certain success, mainly with higher molecular weights and a feature size of ˜30 nm. Several challenges still remain, such as (a) the generation of long-range ordered structure with smaller feature sizes (domain size < 22 nm), (b) obtaining sharp interface between two domains with high lithographic contrast, particularly for smaller feature sizes, and (c) etch selectivity and resistance between two phases in the nanostructure. To address these challenges, several different approaches have been used in our research. First approach is using PS-b-PDMS. PDMS-containing block copolymers have emerged as next generation block copolymers for nanolithography. Their films can be processed under dry conditions using oxygen plasma to produce inorganic, silica patterns which enables their integration into existing device fabrication. Also, the large thermodynamic

  13. Linear optics design of negative momentum compaction lattices for PS2

    SciTech Connect

    Papaphilippou,Y.; de Maria,R.; Barranco, J.; Bartmann, W.; Benedikt, M.; Carli, C.; Goddard, B.; Peggs, S.; Trbojevic, D.

    2009-05-04

    In view of the CERN Proton Synchrotron proposed replacement with a new ring (PS2), a detailed optics design has been undertaken following the evaluation of several lattice options. The basic arc module consists of cells providing negative momentum compaction. The straight section is formed with a combination of FODO and quadrupole triplet cells, to accommodate the injection and extraction systems, in particular the H{sup -} injection elements. The arc is matched to the straight section with a dispersion suppressor and matching module. Different lattices are compared with respect to their linear optics functions, tuning flexibility and geometrical acceptance properties.

  14. Chemical composition effects on the crazing of PS-PMMA block copolymers

    NASA Astrophysics Data System (ADS)

    Kim, Won; Han, Junwon; Yang, Hoichang; Ryu, Chang

    2006-03-01

    Using a large scale separation technique adopting interaction chromatography, we have fractionated as-synthesized PS-PMMA block copolymers in terms of the average chemical composition difference, while maintaining the same average molecular weight. Copper grid technique with optical, atomic force and transmission electron microscopy has been employed for the fracture study to reveal how the composition-dependent morphology affect the crazing of the glassy-glassy block copolymers, while maintaining the same level of Chi*N. In addition, we study how the thermal annealing affects the median strains for crazing and catastrophic failure.

  15. High-throughput gated photon counter with two detection windows programmable down to 70 ps width

    SciTech Connect

    Boso, Gianluca; Tosi, Alberto Zappa, Franco; Mora, Alberto Dalla

    2014-01-15

    We present the design and characterization of a high-throughput gated photon counter able to count electrical pulses occurring within two well-defined and programmable detection windows. We extensively characterized and validated this instrument up to 100 Mcounts/s and with detection window width down to 70 ps. This instrument is suitable for many applications and proves to be a cost-effective and compact alternative to time-correlated single-photon counting equipment, thanks to its easy configurability, user-friendly interface, and fully adjustable settings via a Universal Serial Bus (USB) link to a remote computer.

  16. T3PS v1.0: Tool for Parallel Processing in Parameter Scans

    NASA Astrophysics Data System (ADS)

    Maurer, Vinzenz

    2016-01-01

    T3PS is a program that can be used to quickly design and perform parameter scans while easily taking advantage of the multi-core architecture of current processors. It takes an easy to read and write parameter scan definition file format as input. Based on the parameter ranges and other options contained therein, it distributes the calculation of the parameter space over multiple processes and possibly computers. The derived data is saved in a plain text file format readable by most plotting software. The supported scanning strategies include: grid scan, random scan, Markov Chain Monte Carlo, numerical optimization. Several example parameter scans are shown and compared with results in the literature.

  17. All-fiber based amplification of 40 ps pulses from a gain-switched laser diode.

    PubMed

    Kanzelmeyer, Sebastian; Sayinc, Hakan; Theeg, Thomas; Frede, Maik; Neumann, Joerg; Kracht, Dietmar

    2011-01-31

    Amplification of a gain-switched laser diode is demonstrated in an all-fiber based setup. The amplified spontaneous emission between two consecutive pulses was investigated quantitatively in the time domain. A maximum pulse energy of 13 µJ at a repetition rate of 1 MHz and a pulse duration of 40 ps was extracted, corresponding to a peak power of 270 KW. To the best of our knowledge, this is the highest extracted pulse energy from a laser system seeded by a gain-switched laser diode. Temporal pulse deformation due to intrapulse Raman scattering was observed in the reported system. PMID:21369000

  18. High power laser pulses with voltage controlled durations of 400 - 1000 ps.

    PubMed

    Harth, F; Ulm, T; Lührmann, M; Knappe, R; Klehr, A; Hoffmann, Th; Erbert, G; L'huillier, J A

    2012-03-26

    We report on the generation and amplification of pulses with pulse widths of 400 - 1000 ps at 1064 nm. For pulse generation an ultra-fast semiconductor modulator is used that modulates a cw-beam of a DFB diode laser. The pulse lengths could be adjusted by the use of a voltage control. The pulses were amplified in a solid state Nd:YVO₄ regenerative amplifier to an average power of up to 47.7 W at 100 - 816 kHz. PMID:22453379

  19. Immunological evaluation of the entirely carbohydrate-based Thomsen-Friedenreich - PS B conjugate.

    PubMed

    Trabbic, Kevin R; Bourgault, Jean-Paul; Shi, Mengchao; Clark, Matthew; Andreana, Peter R

    2016-04-01

    PS B, a naturally occurring CD4(+) T-cell simulating zwitterionic polysaccharide from Bacteroides fragilis ATCC 25285/NCTC 9343, was conjugated with aminooxy Thomsen Friedenreich (TF or T) [α-d-Gal-(1,3)-β-d-GalNAc-ONH2] tumor antigen. Immunization in Jax C57BL/6, followed by ELISA revealed IgM and IgG antibody TF specificity. FACS data noted preferential binding to TF-laced MCF-7 cells but not to HCT-116 cells. PMID:26958987

  20. High resolution MR microscopy

    NASA Astrophysics Data System (ADS)

    Ciobanu, Luisa

    Magnetic resonance imaging (MRI) microscopy [1] has the potential to bring the full capabilities of NMR to arbitrarily specified localized positions within small samples. The most interesting target of study is the living biological cell, with typical dimensions ˜100 mum, but with substructures that are much smaller, such as the cell nucleus (typically ˜10 mu m) and mitochondria (1--10 mum). One anticipates that the development of MR microscopy with resolution at the level of these substructures or better and with a wide, three dimensional field-of-view could open a new avenue of investigation into the biology of the living cell. Although the first MR image of a single biological cell was reported in 1987 [2], the cell imaged had quite large (˜1 mm diameter) spatial dimensions and the resolution obtained (on the order of 10 mu m) was not adequate for meaningful imaging of more typically sized cells. The quest for higher resolution has continued. In 1989 Zhou et al. [3] obtained fully three dimensional images with spatial resolution of (6.37 mum)3, or 260 femtoliters. While better "in-plane" resolutions (i.e., the resolution in 2 of the 3 spatial dimensions) have since been obtained, [4, 5] this volume resolution was not exceeded until quite recently by Lee et al., [6] who report 2D images having volume resolution of 75 mum 3 and in-plane resolution of 1 mum. In parallel with these advances in raw resolution several investigators [7, 8, 9] have focused on localized spectroscopy and/or chemical shift imaging. The key obstacles to overcome in MR microscopy are (1) the loss of signal to noise that occurs when observing small volumes and (2) molecular diffusion during the measurement or encoding. To date the problem of sensitivity has typically been addressed by employing small micro-coil receivers. [10] The problem of molecular diffusion can only be defeated with strong magnetic field gradients that can encode spatial information quickly. We report MR microscopy

  1. Simple ps microchip Nd:YVO4 laser with 3.3-ps pulses at 0.2 to 1.4 MHz and single-stage amplification to the microjoule level

    NASA Astrophysics Data System (ADS)

    Türkyilmaz, Erdal; Lohbreier, Jan; Günther, Christian; Mehner, Eva; Kopf, Daniel; Giessen, Harald; Braun, Bernd

    2016-06-01

    Commercial picosecond sources have found widespread applications. Typical system parameters are pulse widths below 20 ps, repetition rates between 0.1 and 2 MHz, and microjoule level pulse energies. Most systems are based on short pulse mode-locked oscillators, regenerative amplifiers, and pockel cells as active beam switches. In contrast, we present a completely passive system, consisting of a passively Q-switched microchip laser, a single-stage amplifier, and a pulse compressor. The Q-switched microchip laser has a 50-μm-long Nd:YVO4 gain material optically bonded to a 4.6-mm-thick undoped YVO4 crystal. It delivers pulse widths of 40 ps and repetition rates of 0.2 to 1.4 MHz at a wavelength of 1.064 μm. The pulse energy is a few nanojoule. These 40-ps pulses are spectrally broadened in a standard single-mode fiber and then compressed in a 24-mm-long chirped Bragg grating to as low as 3.3 ps. The repetition rate can be tuned from ˜0.2 to 1.4 MHz by changing the pump power, while the pulse width and the pulse energy from the microchip laser are unchanged. The spectral broadening in the fiber is observed throughout the pulse repetition rate, supporting sub-10-ps pulses. Finally, the pulses are amplified in a single-stage Nd:YVO4 amplifier up to the microjoule level (up to 4 μJ pulse energy). As a result, the system delivers sub-10-ps pulses at a microjoule level with about 1 MHz repetition rate, and thus fulfills the requirements for ps-micromachining. It does not contain any active switching elements and can be integrated in a very compact setup.

  2. Inverse modeling using PS-InSAR for improved calibration of hydraulic parameters and prediction of future subsidence for Las Vegas Valley, USA

    NASA Astrophysics Data System (ADS)

    Burbey, T. J.; Zhang, M.

    2015-11-01

    Las Vegas Valley has had a long history of surface deformation due to groundwater pumping that began in the early 20th century. After nearly 80 years of pumping, PS-InSAR interferograms have revealed detailed and complex spatial patterns of subsidence in the Las Vegas Valley area that do not coincide with major pumping regions. High spatial and temporal resolution subsidence observations from InSAR and hydraulic head data were used to inversely calibrate transmissivities (T), elastic and inelastic skeletal storage coefficients (Ske and Skv) of the developed-zone aquifer and conductance (CR) of the basin-fill faults for the entire Las Vegas basin. The results indicate that the subsidence observations from PS-InSAR are extremely beneficial for accurately quantifying hydraulic parameters, and the model calibration results are far more accurate than when using only water-levels as observations, and just a few random subsidence observations. Future predictions of land subsidence to year 2030 were made on the basis of existing pumping patterns and rates. Simulation results suggests that subsidence will continue in northwest subsidence bowl area, which is expected to undergo an additional 11.3 cm of subsidence. Even mitigation measures that include artificial recharge and reduced pumping do not significantly reduce the compaction in the northwest subsidence bowl. This is due to the slow draining of thick confining units in the region. However, a small amount of uplift of 0.4 cm is expected in the North and Central bowl areas over the next 20 years.

  3. Lincoln's Spot Resolutions.

    ERIC Educational Resources Information Center

    Mueller, Jean West; Schamel, Wynell Burroughs

    1988-01-01

    Examines the events leading to and immediately following the declaration of war on Mexico in 1846. Includes the second and third pages of Abraham Lincoln's "Spot Resolutions" and presents teaching suggestions for interpreting the document and assessing public opinion. (GEA)

  4. Shower counter resolution scaling

    SciTech Connect

    Kirk, T.B.W.

    1991-10-14

    The EM shower counter for the SDC detector has a resolution expression containing two stochastic terms plus a constant term. Recent measurements clarifying the sources of these terms are presented here. 3 refs., 4 figs.

  5. Measurement of intrinsic rise times for various L(Y)SO and LuAG scintillators with a general study of prompt photons to achieve 10 ps in TOF-PET.

    PubMed

    Gundacker, Stefan; Auffray, Etiennette; Pauwels, Kristof; Lecoq, Paul

    2016-04-01

    The coincidence time resolution (CTR) of scintillator based detectors commonly used in positron emission tomography is well known to be dependent on the scintillation decay time (τd) and the number of photons detected (n'), i.e. CTR proportional variant √τd/n'. However, it is still an open question to what extent the scintillation rise time (τr) and other fast or prompt photons, e.g. Cherenkov photons, at the beginning of the scintillation process influence the CTR. This paper presents measurements of the scintillation emission rate for different LSO type crystals, i.e. LSO:Ce, LYSO:Ce, LSO:Ce codoped Ca and LGSO:Ce. For the various LSO-type samples measured we find an average value of 70 ps for the scintillation rise time, although some crystals like LSO:Ce codoped Ca seem to have a much faster rise time in the order of 20 ps. Additional measurements for LuAG:Ce and LuAG:Pr show a rise time of 535 ps and 251 ps, respectively. For these crystals, prompt photons (Cherenkov) can be observed at the beginning of the scintillation event. Furthermore a significantly lower rise time value is observed when codoping with calcium. To quantitatively investigate the influence of the rise time to the time resolution we measured the CTR with the same L(Y)SO samples and compared the values to Monte Carlo simulations. Using the measured relative light yields, rise- and decay times of the scintillators we are able to quantitatively understand the measured CTRs in our simulations. Although the rise time is important to fully explain the CTR variation for the different samples tested we determined its influence on the CTR to be in the order of a few percent only. This result is surprising because, if only photonstatistics of the scintillation process is considered, the CTR would be proportional to the square root of the rise time. The unexpected small rise time influence on the CTR can be explained by the convolution of the scintillation rate with the single photon time

  6. Measurement of intrinsic rise times for various L(Y)SO and LuAG scintillators with a general study of prompt photons to achieve 10 ps in TOF-PET

    NASA Astrophysics Data System (ADS)

    Gundacker, Stefan; Auffray, Etiennette; Pauwels, Kristof; Lecoq, Paul

    2016-04-01

    The coincidence time resolution (CTR) of scintillator based detectors commonly used in positron emission tomography is well known to be dependent on the scintillation decay time ({τd} ) and the number of photons detected ({{n}\\prime} ), i.e. CTR\\propto \\sqrt{{τd}/{{n}\\prime}} . However, it is still an open question to what extent the scintillation rise time ({τr} ) and other fast or prompt photons, e.g. Cherenkov photons, at the beginning of the scintillation process influence the CTR. This paper presents measurements of the scintillation emission rate for different LSO type crystals, i.e. LSO:Ce, LYSO:Ce, LSO:Ce codoped Ca and LGSO:Ce. For the various LSO-type samples measured we find an average value of 70 ps for the scintillation rise time, although some crystals like LSO:Ce codoped Ca seem to have a much faster rise time in the order of 20 ps. Additional measurements for LuAG:Ce and LuAG:Pr show a rise time of 535 ps and 251 ps, respectively. For these crystals, prompt photons (Cherenkov) can be observed at the beginning of the scintillation event. Furthermore a significantly lower rise time value is observed when codoping with calcium. To quantitatively investigate the influence of the rise time to the time resolution we measured the CTR with the same L(Y)SO samples and compared the values to Monte Carlo simulations. Using the measured relative light yields, rise- and decay times of the scintillators we are able to quantitatively understand the measured CTRs in our simulations. Although the rise time is important to fully explain the CTR variation for the different samples tested we determined its influence on the CTR to be in the order of a few percent only. This result is surprising because, if only photonstatistics of the scintillation process is considered, the CTR would be proportional to the square root of the rise time. The unexpected small rise time influence on the CTR can be explained by the convolution of the scintillation rate with the

  7. Ultra high resolution tomography

    SciTech Connect

    Haddad, W.S.

    1994-11-15

    Recent work and results on ultra high resolution three dimensional imaging with soft x-rays will be presented. This work is aimed at determining microscopic three dimensional structure of biological and material specimens. Three dimensional reconstructed images of a microscopic test object will be presented; the reconstruction has a resolution on the order of 1000 A in all three dimensions. Preliminary work with biological samples will also be shown, and the experimental and numerical methods used will be discussed.

  8. High-Resolution Autoradiography

    NASA Technical Reports Server (NTRS)

    Towe, George C; Gomberg, Henry J; Freemen, J W

    1955-01-01

    This investigation was made to adapt wet-process autoradiography to metallurgical samples to obtain high resolution of segregated radioactive elements in microstructures. Results are confined to development of the technique, which was perfected to a resolution of less than 10 microns. The radioactive samples included carbon-14 carburized iron and steel, nickel-63 electroplated samples, a powder product containing nickel-63, and tungsten-185 in N-155 alloy.

  9. Onset of ice VII phase during ps laser pulse propagation through liquid water

    NASA Astrophysics Data System (ADS)

    Paturi, Prem Kiran; Vaddapally, Rakesh Kumar; Acrhem Team

    2015-06-01

    Water dominantly present in liquid state on earth gets transformed to crystalline polymorphs under different dynamic loading conditions. Out of 15 different crystalline phases discovered till date, ice VII is observed to be stable over wide pressure (2-63 GPa) and temperature (>273 K) ranges. We present the onset of ice VII phase at low threshold of 2 mJ/pulse during 30 ps (532 nm, 10 Hz) laser pulse induced shock propagating through liquid water. Role of input pulse energy on the evolution of Stoke's and anti-Stoke's Raman shift of the dominant A1g mode of ice VII, filamentation, free-electrons, plasma shielding is presented. The H-bond network rearrangement, electron ion energy transfer time coinciding with the excitation pulse duration supported by the filamentation and plasma shielding of the ps laser pulses reduced the threshold of ice VII structure formation. Filamentation and the plasma shielding have shown the localized creation and sustenance of ice VII structure in liquid water over 3 mm length and 50 μm area of cross-section. The work is supported by Defence Research and Developement Organization, India through Grants-in-Aid Program.

  10. A Simple Protocol for the Myocardial Differentiation of Human iPS Cells.

    PubMed

    Aikawa, Nobuo; Suzuki, Yui; Takaba, Katsumi

    2015-01-01

    We have developed a simple protocol for inducing the myocardial differentiation of human induced pluripotent stem (iPS) cells. Human iPS cell-derived embryonic bodies (EBs) were treated with a combination of activin-A, bone morphogenetic protein-4 and wnt-3a for one day in serum-free suspension culture, and were subsequently treated with noggin for three days. Thereafter, the EBs were subjected to adherent culture in media with 5% serum. All EBs were differentiated into spontaneously beating EBs, which were identified by the presence of striated muscles in transmission electron microscopy and the expression of the specific cardiomyocyte markers, NKX2-5 and TNNT2. The beating rate of the beating EBs was decreased by treatment with a rapidly activating delayed rectifier potassium current (Ikr) channel blocker, E-4031, an Ikr trafficking inhibitor, pentamidin, and a slowly activating delayed rectifier potassium current (Iks) channel blocker, chromanol 293B, and was increased by treatment with a beta-receptor agonist, isoproterenol. At a low concentration, verapamil, a calcium channel blocker, increased the beating rate of the beating EBs, while a high concentration decreased this rate. These findings suggest that the spontaneously beating EBs were myocardial cell clusters. This simple protocol for myocardial differentiation would be useful in providing a sufficient number of the beating myocardial cell clusters for studies requiring human myocardium. PMID:26133717

  11. Production and characterization of poly-3-hydroxybutyrate from Bacillus cereus PS 10.

    PubMed

    Sharma, Priyanka; Bajaj, Bijender Kumar

    2015-11-01

    Usage of renewable raw materials for production of fully degradable bioplastics (bacterial poly-3-hydroxybutyrate, PHB) has gained immense research impetus considering recalcitrant nature of petroleum based plastics, dwindling fossil fuel feed stocks, and associated green house gas emissions. However, high production cost of PHB is the major bottleneck for its wide range industrial applications. In current study, Bacillus cereus PS 10, a recent isolate, efficiently utilized molasses, an abundantly available by-product from sugar industries as sole carbon source for growth and PHB production. Most influential bioprocess variables i.e. molasses, pH and NH4Cl were identified based on Plackett-Burman-designed experiments. Design of experiment approach (response surface methodology) was further employed for optimization of these bioprocess variables, and an enhanced PHB yield (57.5%) was obtained. PHB produced by Bacillus cereus PS 10 was investigated using various physico-chemical approaches viz. thermogravimetric analysis, proton and carbon NMR ((1)H and (13)C) spectroscopy, melting point, elemental analysis and polarimetry for its detail characterization, and assessment for industrial application potential. PMID:26257381

  12. [Research on monitoring land subsidence in Beijing plain area using PS-InSAR technology].

    PubMed

    Gu, Zhao-Qin; Gong, Hui-Li; Zhang, You-Quan; Lu, Xue-Hui; Wang, Sa; Wang, Rong; Liu, Huan-Huan

    2014-07-01

    In the present paper, the authors use permanent scatterers synthetic aperture radar interferometry (PS-InSAR) technique and 29 acquisitions by Envisat during 2003 to 2009 to monitor and analyze the spatial-temporal distribution and mechanism characterize of land subsidence in Beijing plain area. The results show that subsidence bowls have been bounded together in Beijing plain area, which covers Chaoyang, Changping, Shunyi and Tongzhou area, and the range of subsidence has an eastward trend. The most serious regional subsidence is mainly distributed by the quaternary depression in Beijing plain area. PS-Insar results also show a new subsidence bowl in Pinggu. What's more, the spatial and temporal distribution of deformation is controlled mainly by faults, such as Liangxiang-Shunyi fault, Huangzhuang-Gaoliying fault, and Nankou-Sunhe fault. The subsidence and level of groundwater in study area shows a good correlation, and the subsidence shows seasonal ups trend during November to March and seasonal downs trend during March to June along with changes in groundwater levels. The contribution of land subsidence is also influenced by stress-strain behavior of aquitards. The compaction of aquitards shows an elastic, plastic, viscoelastic pattern. PMID:25269304

  13. Measurements at TRIUMF on a 80 MHz Cavity Model for the CERN PS Upgrade for LHC.

    NASA Astrophysics Data System (ADS)

    Mitra, A. K.; Poirier, R. L.; Losito, R.

    1997-05-01

    The RF system of the CERN PS being upgraded to bunch a beam that can be captured by the SPS 200 MHz RF system for injection into LHC. Two identical 80 MHz cavities are part of this PS upgrade programme. At CERN, the cavity has been designed using SUPERFISH and MAFIA concerning its shape, tuning devices and amplifier coupling loop. TRIUMF has built a simplified full-scale, copper-lined, wooden model, designed such that the field patters of the fundamental accelerating mode and the longitudinal modes agree closely to CERN cavity ones. The aim of constructing the wooden model was primarily to check the design of the capacitive tuners, the power coupling loop and the HOM dampers for the longitudinal modes up to 1 GHz. The results of the measurements were used to define the parameters of the tuners and a reliable model to describe the interaction of the coupling look with the fundamental mode of the final CERN cavity. Five quarter-wave antennae are adequate to damp the first fifteen longitudinal modes. In order not to decrease the shunt impedance of the fundamental mode by more than 5%, a three-element filter has been used with the antenna which damps the first longitudinal mode at 256 MHz.

  14. Processing of metals and dielectric materials with ps-laserpulses: results, strategies, limitations and needs

    NASA Astrophysics Data System (ADS)

    Neuenschwander, Beat; Bucher, Guido F.; Nussbaum, Christian; Joss, Benjamin; Muralt, Martin; Hunziker, Urs W.; Schuetz, Peter

    2010-02-01

    Ultra short (ps, fs) laser pulses are used, when high requirements concerning accuracy, surface roughness, heat affected zone etc. are demanded for surface structuring. Ps-laser systems that are suited to be operated in industrial environments are of great interest for many practical applications. Here results in the field of 3-d structuring (metals and transparent materials), induced processes and structuring of flexible solar cells will be presented. Beside the pulse duration, which is given by the laser system, the user has a wide variety of optimization parameters such as fluence, repetition rate and wavelength. Based on a simple model it will be shown, that there exist optimum laser parameters to achieve maximum volume ablation rates at a given average power. To take benefit of these optimum parameters and to prevent harmful effects like plasma shielding and surface melting, adapted structuring strategies, depending on the requirements, have to be used. Today's ultra short pulsed systems have average powers from a few W up to a few 10W at high repetition rates. The actual available beam guiding systems are limited and can often not fulfill the requirements needed for high throughput structuring with optimized parameters. Based on the achieved results, the needs for future beam guiding systems will be discussed.

  15. Extracellular thermostable proteolytic activity of the milk spoilage bacterium Pseudomonas fluorescens PS19 on bovine caseins.

    PubMed

    Stuknytė, M; Decimo, M; Colzani, M; Silvetti, T; Brasca, M; Cattaneo, S; Aldini, G; De Noni, I

    2016-06-01

    We studied the thermostable proteolytic activity of Pseudomonas fluorescens PS19 isolated from raw bovine milk. The heat-treated cell-free supernatant (HT-CFS) contained a thermostable protease of approximately 45 kDa, as revealed by casein zymography. We assigned this enzyme to P. fluorescens AprX metalloprotease (UniProtKB Acc. No. C9WKP6). After concentration by ultrafiltration at 10 kDa, the HT-CFS showed 2 other thermostable proteolytic bands on zymogram, with molecular masses of approximately 15 and 25 kDa. The former resulted a fragment of the AprX protease, whereas the 25-kDa protease was not homologous to any known protein of Pseudomonas spp. Subsequently, we assessed the proteolytic activity of the HT-CFS on bovine αS-, β-, and κ-casein during in vitro incubation at 7 or 22°C. By means of ultra-performance liquid chromatography-tandem mass spectrometry we identified the released peptides (n=591). Some of them resisted proteolysis during the whole incubation period at both incubation temperatures and, therefore, they could be assumed as indicators of the proteolytic action of P. fluorescens PS19 on bovine caseins. PMID:26995139

  16. Patterns with PS-b-PMMA block copolymer on various substrates and their applications

    NASA Astrophysics Data System (ADS)

    Alam, Md. Mahbub; Lee, Yu-Rim; Jung, Woo-Gwang

    2011-01-01

    High density arrays of nanostructures over large area can be formed by self-assembly of block copolymers on a variety of substrates such as silica deposited silicon wafer, glass, GaN, PET etc. This block copolymer thin film, such that the domains are oriented perpendicularly to the substrate, is particularly useful for the formation of templates for patterns. The degradation and elimination of the minor component transforms the material into an array of nanopores to form some patterned template that offer potential benefits in a number of applications. The morphology of the polymer surface is strongly dependent on the thickness of the polymer layer. Moreover it is necessary to control the size and shape in order to get the desired properties. Spin coating fallowed by baking the polymer solution onto the substrate self assembles the components of the polymer. PS and PMMA have significantly different photodegradation properties. Exposure to ultraviolet radiation degrades the PMMA (polymethyl methacrylate) chain that can be removed by rinsing in acetic acid giving patterned holes. Sonicating the samples in different solutions in different steps gives fingerprint pattern or sometimes patterns with PS cylindrical domains with large interstitial spaces. Moreover the interstitial space depends on the composition of the polymer solution. All these controlled patterns made on GaN, Glass can be applied to make photonic crystal

  17. Derivation of LIF-independent mouse iPS cells with modified Oct4

    PubMed Central

    Hirai, Hiroyuki; Firpo, Meri; Kikyo, Nobuaki

    2015-01-01

    It has been very difficult, if not impossible, to establish mouse induced pluripotent stem cells (iPSCs) from differentiated cells, such as fibroblasts, without leukemia inhibitory factor (LIF). We have established and maintained LIF-independent iPSCs for longer than 120 days with modified Oct4 along with Sox2, Klf4, and c-Myc. The iPSCs will provide a novel tool to investigate the roles of the LIF-Stat3 signaling pathway in mouse pluripotent stem cells. Resource TableBiological reagent: induced pluripotent stem (iPS) cellName of Stem Cell constructM3O-lenti-iPSC-LIF(−)InstitutionUniversity of MinnesotaPerson who created resourceHiroyuki HiraiContact person and emailNobuaki Kikyo, kikyo001@umn.eduDate archived/stock date2014–2015OriginMouse embryonic fibroblastsType of resourceBiological reagent: induced pluripotent stem (iPS) cellSub-typeCell lineKey transcription factorsM3O, Sox2, Klf4, c-MycAuthenticationIdentity and purity of cell line confirmed (Figure 1)Link to related literature (direct URL links and full references)Hirai H., et al. In press, Stem Cell ResearchInformation in public databases PMID:26318720

  18. Unusual Thermal Stability of RNA/[RP-PS]-DNA/RNA Triplexes Containing a Homopurine DNA Strand

    PubMed Central

    Guga, Piotr; Boczkowska, Małgorzata; Janicka, Magdalena; Maciaszek, Anna; Kuberski, Sławomir; Stec, Wojciech J.

    2007-01-01

    Homopurine deoxyribonucleoside phosphorothioates, as short as hexanucleotides and possessing all internucleotide linkages of RP configuration, form a triple helix with two RNA or 2′-OMe-RNA strands, with Watson-Crick and Hoogsteen complementarity. Melting temperature and fluorescence quenching experiments strongly suggest that the Hoogsteen RNA strand is parallel to the homopurine [RP-PS]-oligomer. Remarkably, these triplexes are thermally more stable than complexes formed by unmodified homopurine DNA molecules of the same sequence. The triplexes formed by phosphorothioate DNA dodecamers containing 4–6 dG residues are thermally stable at pH 7.4, although their stability increases significantly at pH 5.3. FTIR measurements suggest participation of the C2-carbonyl group of the pyrimidines in the stabilization of the triplex structure. Formation of triple-helix complexes with exogenously delivered PS-oligos may become useful for the reduction of RNA accessibility in vivo and, hence, selective suppression/inhibition of the translation process. PMID:17218459

  19. Mitochondrial Parkin recruitment is impaired in neurons derived from mutant PINK1 iPS cells

    PubMed Central

    Seibler, Philip; Graziotto, John; Jeong, Hyun; Simunovic, Filip; Klein, Christine; Krainc, Dimitri

    2011-01-01

    Genetic Parkinson disease (PD) has been associated with mutations in PINK1, a gene encoding a mitochondrial kinase implicated in the regulation of mitochondrial degradation. While the studies so far examined PINK1 function in non-neuronal systems or through PINK1 knockdown approaches, there is an imperative to examine the role of endogenous PINK1 in appropriate human-derived and biologically relevant cell models. Here we report the generation of induced pluripotent stem (iPS) cells from skin fibroblasts taken from three PD patients with nonsense (c.1366C>T; p.Q456X) or missense mutations (c.509T>G; p.V170G) in the PINK1 gene. These cells were differentiated into dopaminergic neurons that upon mitochondrial depolarization showed impaired recruitment of lentivirally expressed Parkin to mitochondria, increased mitochondrial copy number and upregulation of PGC-1α, an important regulator of mitochondrial biogenesis. Importantly, these alterations were corrected by lentiviral expression of wild-type PINK1 in mutant iPS cell-derived PINK1 neurons. In conclusion, our studies suggest that fibroblasts from genetic PD can be reprogrammed and differentiated into neurons. These neurons exhibit distinct phenotypes that should be amenable to further mechanistic studies in this relevant biological context. PMID:21508222

  20. hiPS-MSCs differentiation towards fibroblasts on a 3D ECM mimicking scaffold.

    PubMed

    Xu, Ruodan; Taskin, Mehmet Berat; Rubert, Marina; Seliktar, Dror; Besenbacher, Flemming; Chen, Menglin

    2015-01-01

    Fibroblasts are ubiquitous cells that constitute the stroma of virtually all tissues and play vital roles in homeostasis. The poor innate healing capacity of fibroblastic tissues is attributed to the scarcity of fibroblasts as collagen-producing cells. In this study, we have developed a functional ECM mimicking scaffold that is capable to supply spatial allocation of stem cells as well as anchorage and storage of growth factors (GFs) to direct stem cells differentiate towards fibroblasts. Electrospun PCL fibers were embedded in a PEG-fibrinogen (PF) hydrogel, which was infiltrated with connective tissue growth factor (CTGF) to form the 3D nanocomposite PFP-C. The human induced pluripotent stem cells derived mesenchymal stem cells (hiPS-MSCs) with an advance in growth over adult MSCs were applied to validate the fibrogenic capacity of the 3D nanocomposite scaffold. The PFP-C scaffold was found not only biocompatible with the hiPS-MSCs, but also presented intriguingly strong fibroblastic commitments, to an extent comparable to the positive control, tissue culture plastic surfaces (TCP) timely refreshed with 100% CTGF. The novel scaffold presented not only biomimetic ECM nanostructures for homing stem cells, but also sufficient cell-approachable bio-signaling cues, which may synergistically facilitate the control of stem cell fates for regenerative therapies. PMID:25684543

  1. Correlation of anisotropy and directional conduction in β-Li3PS4 fast Li+ conductor

    NASA Astrophysics Data System (ADS)

    Chen, Yan; Cai, Lu; Liu, Zengcai; dela Cruz, Clarina R.; Liang, Chengdu; An, Ke

    2015-07-01

    This letter reports the correlation of anisotropy and directional conduction in the fast Li+ conductor β-Li3PS4, one of the low-symmetry crystalline electrolyte candidates. The material has both high conductivity and good stability that serves well for the large-scale energy storage applications of all-solid-state lithium ion batteries. The anisotropic physical properties, demonstrated here by the thermal expansion coefficients, are crucial for compatibility in the solid-state system and battery performance. Neutron and X-ray powder diffraction measurements were done to determine the crystal structure and thermal stability. The crystallographic b-axis was revealed as a fast expansion direction, while negligible thermal expansion was observed along the a-axis around the battery operating temperatures. The anisotropic behavior has its structural origin from the Li+ conduction channels with incomplete Li occupancy and a flexible connection of LiS4 and PS4 tetrahedra within the framework. This indicates a strong correlation in the direction of the ionic transport in the low-symmetry Li+ conductor.

  2. hiPS-MSCs differentiation towards fibroblasts on a 3D ECM mimicking scaffold

    PubMed Central

    Xu, Ruodan; Taskin, Mehmet Berat; Rubert, Marina; Seliktar, Dror; Besenbacher, Flemming; Chen, Menglin

    2015-01-01

    Fibroblasts are ubiquitous cells that constitute the stroma of virtually all tissues and play vital roles in homeostasis. The poor innate healing capacity of fibroblastic tissues is attributed to the scarcity of fibroblasts as collagen-producing cells. In this study, we have developed a functional ECM mimicking scaffold that is capable to supply spatial allocation of stem cells as well as anchorage and storage of growth factors (GFs) to direct stem cells differentiate towards fibroblasts. Electrospun PCL fibers were embedded in a PEG-fibrinogen (PF) hydrogel, which was infiltrated with connective tissue growth factor (CTGF) to form the 3D nanocomposite PFP-C. The human induced pluripotent stem cells derived mesenchymal stem cells (hiPS-MSCs) with an advance in growth over adult MSCs were applied to validate the fibrogenic capacity of the 3D nanocomposite scaffold. The PFP-C scaffold was found not only biocompatible with the hiPS-MSCs, but also presented intriguingly strong fibroblastic commitments, to an extent comparable to the positive control, tissue culture plastic surfaces (TCP) timely refreshed with 100% CTGF. The novel scaffold presented not only biomimetic ECM nanostructures for homing stem cells, but also sufficient cell-approachable bio-signaling cues, which may synergistically facilitate the control of stem cell fates for regenerative therapies. PMID:25684543

  3. PS-1/S1 picosecond streak camera application for multichannel laser system diagnostics

    SciTech Connect

    Garanin, S G; Bel'kov, S A; Rogozhnikov, G S; Rukavishnikov, N N; Romanov, V V; Voronich, I N; Vorob'ev, N S; Gornostaev, P B; Lozovoi, V I; Shchelev, M Ya

    2014-08-31

    A PS-1/S1 picosecond image-tube streak camera (ITSC) with slit scan (streak camera), developed and manufactured at the General Physics Institute RAS, has been used to measure the spatiotemporal characteristics of ultrashort laser pulses generated by a petawatt-power laser installation 'FEMTO' at the Institute of Laser Physics Research in Sarov. It is found that such a camera is suitable for measuring the spatial and temporal parameters of single laser pulses with an accuracy of about one picosecond. It is shown that the intensity time profile of a train of picosecond pulses may be precisely defined for the pulses separated in time by a few picoseconds. The camera allows the contrast of radiation to be determined with a high (no less than 10{sup 3}) accuracy; spatial distribution of the laser pulses can be measured with an accuracy of tens of microns, and the temporal separation of single laser pulses can be identified with an accuracy of 1 – 1.5 ps. (extreme light fields and their applications)

  4. Plasma Spray-Physical Vapor Deposition (PS-PVD) of Ceramics for Protective Coatings

    NASA Technical Reports Server (NTRS)

    Harder, Bryan J.; Zhu, Dongming

    2011-01-01

    In order to generate advanced multilayer thermal and environmental protection systems, a new deposition process is needed to bridge the gap between conventional plasma spray, which produces relatively thick coatings on the order of 125-250 microns, and conventional vapor phase processes such as electron beam physical vapor deposition (EB-PVD) which are limited by relatively slow deposition rates, high investment costs, and coating material vapor pressure requirements. The use of Plasma Spray - Physical Vapor Deposition (PS-PVD) processing fills this gap and allows thin (< 10 microns) single layers to be deposited and multilayer coatings of less than 100 microns to be generated with the flexibility to tailor microstructures by changing processing conditions. Coatings of yttria-stabilized zirconia (YSZ) were applied to NiCrAlY bond coated superalloy substrates using the PS-PVD coater at NASA Glenn Research Center. A design-of-experiments was used to examine the effects of process variables (Ar/He plasma gas ratio, the total plasma gas flow, and the torch current) on chamber pressure and torch power. Coating thickness, phase and microstructure were evaluated for each set of deposition conditions. Low chamber pressures and high power were shown to increase coating thickness and create columnar-like structures. Likewise, high chamber pressures and low power had lower growth rates, but resulted in flatter, more homogeneous layers

  5. Poisson's ratio prediction through dual stimulated fuzzy logic by ACE and GA-PS

    NASA Astrophysics Data System (ADS)

    Bagheripour, Parisa; Asoodeh, Mojtaba

    2014-08-01

    Poisson's ratio is one of the most important rock mechanical parameters having significance in both planning and post analysis of wellbore operations. Laboratory measurement of this parameter covers a broad range of costs, including sidewall sampling, preservation, and laboratory tests. This study proposes an improved strategy, called dual stimulated fuzzy logic by ACE and GA-PS for determining Poisson's ratio from conventional well log data in a rapid, precise, and cost-effective way. Firstly, conventional well log data are transformed to a higher correlated data space with Poisson's ratio through the use of alternative condition expectation (ACE) algorithm. This step simplifies the convoluted space of the problem and makes it easier to solve for fuzzy logic. Subsequently, transformed conventional well log data are fed to fuzzy logic model. To ensure that optimal fuzzy model is constructed, a hybrid genetic algorithm-pattern search (GA-PS) technique is employed for extracting fuzzy clusters (or rules). This step sets fuzzy logic to its optimal performance. The propounded strategy was successfully applied to data from carbonate reservoir rocks of an Iranian Oil Field. A comparison between present model and previous models showed superiority of current study.

  6. Ablation processing of biomedical materials by ultrashort laser pulse ranging from 50 fs through 2 ps

    NASA Astrophysics Data System (ADS)

    Ozono, Kazue; Obara, Minoru; Sakuma, Jun

    2003-06-01

    In recent years, femtosecond laser processing of human hard/soft tissues has been studied. Here, we have demonstrated ablation etching of hydroxyapatite. Hydroxyapatite (Ca10(PO4)6(OH)2) is a key component of human tooth and human bone. The human bone is mainly made of hydroxyapatite oriented along the collagen. The micromachining of hydroxyapatite is highly required for orthopedics and dentistry. The important issue is to preserve the chemical property of the ablated surface. If chemical properties of hydroxyapatite change once, the human bone or tooth cannot grow again after laser processing. As for nanosecond laser ablation (for example excimer laser ablation), the relative content of calcium and phosphorus in (Ca10(PO4)6(OH)2) is found to change after laser ablation. We used here pulsewidth tunable output from 50 fs through 2 ps at 820 nm and 1 kpps. We measured calcium spectrum and phosphorus spectrum of the ablated surface of hydroxyapatite by XPS. As a result, the chemical content of calcium and phosphorus is kept unchanged before and after 50-fs - 2-ps laser ablation. We also demonstrated ablation processing of human tooth with Ti:sapphire laser, and precise ablation processing and microstructure fabrication are realized.

  7. Detecting Land Subsidence in Shanghai by PS-Networking SAR Interferometry

    PubMed Central

    Liu, Guoxiang; Luo, Xiaojun; Chen, Qiang; Huang, Dingfa; Ding, Xiaoli

    2008-01-01

    Existing studies have shown that satellite synthetic aperture radar (SAR) interferometry has two apparent drawbacks, i.e., temporal decorrelation and atmospheric contamination, in the application of deformation mapping. It is however possible to improve deformation analysis by tracking some natural or man-made objects with steady radar reflectivity, i.e., permanent scatterers (PS), in the frame of time series of SAR images acquired over the same area. For detecting land subsidence in Shanghai, China, this paper presents an attempt to explore an approach of PS-neighborhood networking SAR interferometry. With use of 26 ERS-1/2 SAR images acquired 1992 through 2002 over Shanghai, the analysis of subsiding process in time and space is performed on the basis of a strong network which is formed by connecting neighboring PSs according to a distance threshold. The linear and nonlinear subsidence, atmospheric effects as well as topographic errors can be separated effectively in this way. The subsidence velocity field in 10 years over Shanghai is also derived. It was found that the annual subsidence rates in the study area range from -2.1 to -0.6 cm/yr, and the averaged subsidence rate reaches -1.1 cm/yr.

  8. Regrouping of the beam in the IHEP PS for the UNK p-p programs

    NASA Astrophysics Data System (ADS)

    Myae, E. A.; Nelipovich, E. S.; Pashkov, P. T.; Smirnov, A. V.

    Possibilities to form particle bunches in the IHEP machine whose longitudinal parameters would satisfy the requirements imposed by the UNK p-p programs are analyzed. In the case of the 3 x 3 TeV p-p program the accelerated proton beam in the IHEP PS after preliminary quasiadiabatic debunching process will be recaptured into a stable oscillating mode at 33.3 MHz. The peculiarities of the RF system designed for these purposes with an account of strong beam loading are discussed. For the 0.4 x 3 TeV UNK colliding beam regime, it is necessary to compress the accelerated proton bunches in the IHEP PS so that their length will be 4 times less. The main difficulties arising during 'RF gymnastics' which is used for beam compressing, are caused by nonlinearities of the external accelerating field and also the fields induced in the RF cavities by the beam. The compensation of such effects with the help of the special RF system is discussed.

  9. Particle Morphology Effects on Flow Characteristics of PS304 Plasma Spray Coating Feedstock Powder Blend

    NASA Technical Reports Server (NTRS)

    Stanford, Malcolm K.; DellaCorte, Christopher; Eylon, Daniel

    2002-01-01

    The effects of BaF2-CaF 2 particle morphology on PS304 feedstock powder flow ability have been investigated. BaF2-CaF2 eutectic powders were fabricated by comminution (angular) and by gas atomization (spherical). The fluoride powders were added incrementally to the other powder constituents of the PS304 feedstock: nichrome, chromia, and silver powders. A linear relationship between flow time and concentration of BaF2-CaF2 powder was found. Flow of the powder blend with spherical BaF2-CaF2 was better than the angular BaF2-CaF2. Flow ability of the powder blend with angular fluorides decreased linearly with increasing fluoride concentration. Flow of the powder blend with spherical fluorides was independent of fluoride concentration. Results suggest that for this material blend, particle morphology plays a significant role in powder blend flow behavior, offering potential methods to improve powder flow ability and enhance the commercial potential. These findings may have applicability to other difficult-to-flow powders such as cohesive ceramics.

  10. Postmodification of PS-b-P4VP diblock copolymer membranes by ARGET ATRP.

    PubMed

    Keskin, Damla; Clodt, Juliana I; Hahn, Janina; Abetz, Volker; Filiz, Volkan

    2014-07-29

    The surfaces of polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) diblock copolymer membranes were modified in order to obtain polymer brushes by using surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP). Isoporous membranes were prepared by the combination of self-assembly of PS-b-P4VP diblock copolymers and the nonsolvent induced phase separation process, also known as "phase inversion". In order to allow further functionalization, the membranes were modified with an ATRP initiator, 2-bromoisobutyryl bromide (BIBB). Therefore, the mussel-inspired poly(dopamine) coating was used to attach BIBB on the membranes surface. In the next step the coated membranes were postmodified by using surface-initiated ARGET ATRP with the hydrophilic monomer 2-hydroxyethyl methacrylate (HEMA). HEMA as a hydrophilic methacrylate was chosen for the modification in order to enhance the membrane characteristics and to obtain a surface with antifouling properties. The surface-initiated ARGET ATRP reaction was carried out using different reaction times and environments. PHEMA could successfully incorporate on the membrane surface as confirmed by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), (1)H nuclear magnetic resonance spectroscopy ((1)H NMR), scanning electron microscopy (SEM), and contact angle measurements. Furthermore, stability tests against heat and solvents were performed, and water flux was measured for the raw and modified membranes. Stability against heat and hydrophilicity could be increased with this type of modification for diblock copolymer membranes. PMID:24948370

  11. PS-1/S1 picosecond streak camera application for multichannel laser system diagnostics

    NASA Astrophysics Data System (ADS)

    Garanin, S. G.; Bel'kov, S. A.; Rogozhnikov, G. S.; Rukavishnikov, N. N.; Romanov, V. V.; Voronich, I. N.; Vorob'ev, N. S.; Gornostaev, P. B.; Lozovoi, V. I.; Shchelev, M. Ya

    2014-08-01

    A PS-1/S1 picosecond image-tube streak camera (ITSC) with slit scan (streak camera), developed and manufactured at the General Physics Institute RAS, has been used to measure the spatiotemporal characteristics of ultrashort laser pulses generated by a petawatt-power laser installation 'FEMTO' at the Institute of Laser Physics Research in Sarov. It is found that such a camera is suitable for measuring the spatial and temporal parameters of single laser pulses with an accuracy of about one picosecond. It is shown that the intensity time profile of a train of picosecond pulses may be precisely defined for the pulses separated in time by a few picoseconds. The camera allows the contrast of radiation to be determined with a high (no less than 103) accuracy; spatial distribution of the laser pulses can be measured with an accuracy of tens of microns, and the temporal separation of single laser pulses can be identified with an accuracy of 1 - 1.5 ps.

  12. Selective precipitation of Cu from Zn in a pS controlled continuously stirred tank reactor.

    PubMed

    Sampaio, R M M; Timmers, R A; Xu, Y; Keesman, K J; Lens, P N L

    2009-06-15

    Copper was continuously and selectively precipitated with Na(2)S to concentrations below 0.3 ppb from water containing around 600 ppm of both Cu and Zn in a Continuously Stirred Tank Reactor. The pH was controlled at 3 and the pS at 25 (pS=-log(S(2-))) by means of an Ag(2)S sulfide selective electrode. Copper's recovery and purity were about 100%, whereas the total soluble sulfide concentration was below 0.02 ppm. X-ray diffraction (XRD) analysis showed that copper precipitated as hexagonal CuS (covellite). The mode of the particle size distribution (PSD) of the CuS precipitates was around 36 microm. The PSD increased by high pS values and by the presence of Zn. Depending on the turbulence, the CuS precipitates can grow up to 200 microm or fragment in particles smaller than 3 microm in a few seconds. Zn precipitation with Na(2)S at pH 3 and 4, in batch, always lead to Zn concentrations above 1 ppm. Zn precipitated as cubic ZnS (spharelite). PMID:19019537

  13. Correlation of anisotropy and directional conduction in β-Li3PS4 fast Li+ conductor

    DOE PAGESBeta

    Chen, Yan; Cai, Lu; Liu, Zengcai; dela Cruz, Clarina R.; Liang, Chengdu; An, Ke

    2015-07-06

    Our letter reports the correlation of anisotropy and directional conduction in the fast Li+ conductor β-Li3PS4, one of the low-symmetry crystalline electrolyte candidates. The material has both high conductivity and good stability that serves well for the large-scale energy storage applications of all-solid-state lithium ion batteries. The anisotropic physical properties, demonstrated here by the thermal expansion coefficients, are crucial for compatibility in the solid-state system and battery performance. Neutron and X-ray powder diffraction measurements were done to determine the crystal structure and thermal stability. Moreover, the crystallographic b-axis was revealed as a fast expansion direction, while negligible thermal expansion wasmore » observed along the a-axis around the battery operating temperatures. The anisotropic behavior has its structural origin from the Li+ conduction channels with incomplete Li occupancy and a flexible connection of LiS4 and PS4 tetrahedra within the framework. This indicates a strong correlation in the direction of the ionic transport in the low-symmetry Li+ conductor.« less

  14. In situ monitoring of the hydration process of K-PS geopolymer cement with ESEM

    SciTech Connect

    Sun Wei; Zhang Yunsheng; Lin Wei; Liu Zhiyong

    2004-06-01

    Environmental scanning electron microscope (ESEM) was used to in situ quantitatively study the hydration process of K-PS geopolymer cement under an 80% RH environment. An energy dispersion X-ray analysis (EDXA) was also employed to distinguish the chemical composition of hydration product. The ESEM micrographs showed that metakaolin particles pack loosely at 10 min after mixing, resulting in the existence of many large voids. As hydration proceeds, a lot of gels were seen and gradually precipitated on the surfaces of these particles. At later stage, these particles were wrapped by thick gel layers and their interspaces were almost completely filled. The corresponding EDXA results illustrated that the molar ratios of K/Al increase while Si/Al decrease with the development of hydration. As a result, the molar ratios of K/Al and Si/Al of hydration products at an age of 4 h amounted to 0.99 and 1.49, respectively, which were close to the theoretical values (K/Al=1.0, Si/Al=1.0 for K-PS geopolymer cement paste). In addition, well-developed crystals could not been found at any ages; instead, spongelike amorphous gels were always been observed.

  15. Performance of a 512 x 512 Gated CMOS Imager with a 250 ps Exposure Time

    SciTech Connect

    Teruya, A T; Moody, J D; Hsing, W W; Brown, C G; Griffin, M; Mead, A S; Tran, V

    2012-10-01

    We describe the performance of a 512x512 gated CMOS read out integrated circuit (ROIC) with a 250 ps exposure time. A low-skew, H-tree trigger distribution system is used to locally generate individual pixel gates in each 8x8 neighborhood of the ROIC. The temporal width of the gate is voltage controlled and user selectable via a precision potentiometer. The gating implementation was first validated in optical tests of a 64x64 pixel prototype ROIC developed as a proof-of-concept during the early phases of the development program. The layout of the H-Tree addresses each quadrant of the ROIC independently and admits operation of the ROIC in two modes. If “common mode” triggering is used, the camera provides a single 512x512 image. If independent triggers are used, the camera can provide up to four 256x256 images with a frame separation set by the trigger intervals. The ROIC design includes small (sub-pixel) optical photodiode structures to allow test and characterization of the ROIC using optical sources prior to bump bonding. Reported test results were obtained using short pulse, second harmonic Ti:Sapphire laser systems operating at λ~ 400 nm at sub-ps pulse widths.

  16. Performance of a 512 x 512 gated CMOS imager with a 250 ps exposure time

    NASA Astrophysics Data System (ADS)

    Teruya, Alan T.; Vernon, Stephen P.; Moody, James D.; Hsing, Warren W.; Brown, Christopher G.; Griffin, Matthew; Mead, Andrew S.; Tran, Vu

    2012-10-01

    We describe the performance of a 512x512 gated CMOS read out integrated circuit (ROIC) with a 250 ps exposure time. A low-skew, H-tree trigger distribution system is used to locally generate individual pixel gates in each 8x8 neighborhood of the ROIC. The temporal width of the gate is voltage controlled and user selectable via a precision potentiometer. The gating implementation was first validated in optical tests of a 64x64 pixel prototype ROIC developed as a proof-of-concept during the early phases of the development program. The layout of the H-Tree addresses each quadrant of the ROIC independently and admits operation of the ROIC in two modes. If "common mode" triggering is used, the camera provides a single 512x512 image. If independent triggers are used, the camera can provide up to four 256x256 images with a frame separation set by the trigger intervals. The ROIC design includes small (sub-pixel) optical photodiode structures to allow test and characterization of the ROIC using optical sources prior to bump bonding. Reported test results were obtained using short pulse, second harmonic Ti:Sapphire laser systems operating at λ~ 400 nm at sub-ps pulse widths.

  17. Perl-speaks-NONMEM (PsN)--a Perl module for NONMEM related programming.

    PubMed

    Lindbom, Lars; Ribbing, Jakob; Jonsson, E Niclas

    2004-08-01

    The NONMEM program is the most widely used nonlinear regression software in population pharmacokinetic/pharmacodynamic (PK/PD) analyses. In this article we describe a programming library, Perl-speaks-NONMEM (PsN), intended for programmers that aim at using the computational capability of NONMEM in external applications. The library is object oriented and written in the programming language Perl. The classes of the library are built around NONMEM's data, model and output files. The specification of the NONMEM model is easily set or changed through the model and data file classes while the output from a model fit is accessed through the output file class. The classes have methods that help the programmer perform common repetitive tasks, e.g. summarising the output from a NONMEM run, setting the initial estimates of a model based on a previous run or truncating values over a certain threshold in the data file. PsN creates a basis for the development of high-level software using NONMEM as the regression tool. PMID:15212851

  18. Ultrafast, high resolution, phase contrast imaging of impact response with synchrotron radiation

    SciTech Connect

    Jensen, B. J.; Luo, S. N.; Hooks, D. E.; Ramos, K. J.; Yeager, J. D.; Kwiatkowski, K.; Shimada, T.; Dattelbaum, D. M.; Fezzaa, K.

    2012-03-15

    Understanding the dynamic response of materials at extreme conditions requires diagnostics that can provide real-time, in situ, spatially resolved measurements on the nanosecond timescale. The development of methods such as phase contrast imaging (PCI) typically used at synchrotron sources offer unique opportunities to examine dynamic material response. In this work, we report ultrafast, high-resolution, dynamic PCI measurements of shock compressed materials with 3 {mu}m spatial resolution using a single 60 ps synchrotron X-ray bunch. These results firmly establish the use of PCI to examine dynamic phenomena at ns to {mu}s timescales.

  19. Determining time resolution of microchannel plate detectors for electron time-of-flight spectrometers.

    PubMed

    Zhang, Qi; Zhao, Kun; Chang, Zenghu

    2010-07-01

    The temporal resolution of a 40 mm diameter chevron microchannel plate (MCP) detector followed by a constant fraction discriminator and a time-to-digital converter was determined by using the third order harmonic of 25 fs Ti:sapphire laser pulses. The resolution was found to deteriorate from 200 to 300 ps as the total voltage applied on the two MCPs increased from 1600 to 2000 V. This was likely due to a partial saturation of the MCP and/or the constant fraction discriminator working with signals beyond its optimum range of pulse width and shape. PMID:20687710

  20. High-sensitivity high-resolution dual-function signal and time digitizer

    NASA Astrophysics Data System (ADS)

    Sarwana, Saad; Gupta, Deepnarayan; Kirichenko, Alex F.; Oku, Takayuki; Otani, Chiko; Sato, Hiromi; Shimizu, Hirohiko M.

    2002-03-01

    We have developed a dual-function high sensitivity/high-resolution digitizer. It consists of a superconducting digital integrated circuit, which can operate both as a time-to-digital converter (TDC) and a flux counting analog-to-digital converter (ADC). The TDC has a 30 ps multihit time resolution. The ADC has been designed with a superconducting quantum interference device based detector for a 1 μA full scale range. This digitizer is extremely useful in many applications, e.g., for time-of-flight measurements, or as a radiation resistant, low-noise, low-power ADC for detector readout.