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Sample records for pribrezhnykh ehkosistemakh posle

  1. Fading test using the SAAD-POSL method for retrospective accidental dosimetry of building materials

    NASA Astrophysics Data System (ADS)

    Kim, M. J.; Lee, Y. J.; Lee, J. I.; Kim, J. L.; Hong, D. G.

    2015-11-01

    Fading test using the single aliquot additive dose method with pulsed optically stimulated luminescence (SAAD-POSL method) was applied to core-disc samples extracted from heated red brick, tile, roof-tile, and toilet porcelain after X-ray and beta irradiation. From thermoluminescence measurements of each material, the optimal preheat condition of the SAAD-POSL method was first determined as 170 °C for 10 s. Fading characteristics of core-disc samples of heated red brick obtained using the SAAD-POSL method were similar to those of quartz grains (90-250 μm) obtained using the SAR-OSL method, regardless of the differences in the sample and radiation type. Fading evaluations of the core-disc samples of these building materials two weeks after irradiation showed that the equivalent dose (ED) decreased between 5% and 42%. The results indicate that the fading characteristics will be able to contribute to a more accurate estimation of the ED value using the SAAD-POSL method.

  2. Purification, Characterization, and Functional Role of a Novel Extracellular Protease from Pleurotus ostreatus

    PubMed Central

    Palmieri, Gianna; Bianco, Carmen; Cennamo, Giovanna; Giardina, Paola; Marino, Gennaro; Monti, Maria; Sannia, Giovanni

    2001-01-01

    A new extracellular protease (PoSl; Pleurotus ostreatus subtilisin-like protease) from P. ostreatus culture broth has been purified and characterized. PoSl is a monomeric glycoprotein with a molecular mass of 75 kDa, a pI of 4.5, and an optimum pH in the alkaline range. The inhibitory profile indicates that PoSl is a serine protease. The N-terminal and three tryptic peptide sequences of PoSl have been determined. The homology of one internal peptide with conserved sequence around the Asp residue of the catalytic triad in the subtilase family suggests that PoSl is a subtilisin-like protease. This hypothesis is further supported by the finding that PoSl hydrolysis sites of the insulin B chain match those of subtilisin. PoSl activity is positively affected by calcium. A 10-fold decrease in the Km value in the presence of calcium ions can reflect an induced structural change in the substrate recognition site region. Furthermore, Ca2+ binding slows PoSl autolysis, triggering the protein to form a more compact structure. These effects have already been observed for subtilisin and other serine proteases. Moreover, PoSl protease seems to play a key role in the regulation of P. ostreatus laccase activity by degrading and/or activating different isoenzymes. PMID:11375191

  3. Site of Action of Antidiuretic Hormone on Mammalian Nephrons.

    DTIC Science & Technology

    1981-01-01

    techniques. Na and K concen- trations were determined by flamirne photometry and Cl by coulombmetric titration. 3ILO 14C- inulin and "Na were...of Cr in sequential Slop-flow samples. The appearance of 14C- inulin deriv ed from the posl-stop-Ilow IV infusion signalled the appearance of fresh

  4. Innovative Navigation Systems to Support Digital Geophysical Mapping

    DTIC Science & Technology

    2004-02-01

    9 Figure 8. Blackhawk/ Applanix GPS/INS System.................................................................10 Figure 9. Figure-Eight Traverse...Vulcan/LaserStation Line-of-sight laser Parsons Trimble INS/GPS DGPS and inertia guidance Blackhawk Applanix INS/GPS DGPS and inertia guidance...The Applanix Positioning and Orientation System for Land Survey (POS/LS) was used for the Phase I work. The system is similar to the Parsons

  5. A short-time fading study of Al2O3:C

    NASA Astrophysics Data System (ADS)

    Nascimento, L. F.; Vanhavere, F.; Silva, E. H.; Deene, Y. De

    2015-01-01

    This paper studies the short-time fading from Al2O3:C by measuring optically stimulated luminescence (OSL) signals (Total OSL: TOSL, and Peak OSL: POSL) from droplets and Luxel™ pellets. The influence of various bleaching regimes (blue, green and white) and light power is compared. The fading effect is the decay of the OSL signal in the dark at room temperature. Al2O3:C detectors were submitted to various bleaching regimes, irradiated with a reference dose and read out after different time spans. Investigations were carried out using 2 mm size droplet detectors, made of thin Al2O3:C powder mixed with a photocured polymer. Tests were compared to Luxel™-type detectors (Landauer Inc.). Short-time post-irradiation fading is present in OSL results (TOSL and POSL) droplets for time spans up to 200 s. The effect of short-time fading can be lowered/removed when treating the detectors with high-power and/or long time bleaching regimes; this result was observed in both TOSL and POSL from droplets and Luxel™.

  6. SU-E-T-592: OSL Response of Al2O3:C Detectors Exposed to Therapeutic Proton Beams

    SciTech Connect

    Granville, DA; Flint, DB; Sawakuchi, GO

    Purpose: To characterize the response of Al{sub 2}O{sub 3}:C optically stimulated luminescence (OSL) detectors (OSLDs) exposed to therapeutic proton beams of differing beam quality. Methods: We prepared Al{sub 2}O{sub 3}:C OSLDs from the same material as commercially available nanoDot dosimeters (Landauer, Inc). We irradiated the OSLDs in modulated proton beams of varying quality, as defined by the residual range. An absorbed dose to water of 0.2 Gy was delivered to all OSLDs with the residual range values varying from 0.5 to 23.5 cm (average LET in water from ∼0.5 to 2.5 keV/µm). To investigate the beam quality dependence of differentmore » emission bands within the OSL spectrum, we performed OSLD readouts using both continuous-wave stimulation (CW-OSL) and pulsed stimulation (P-OSL) with two sets of optical filters (Hoya U-340 and Kopp 5113). For all readout modes, the relative absorbed dose sensitivity ( S{sub rel}) for each beam quality was calculated using OSLDs irradiated in a 6 MV photon beam as a reference. Results: We found that the relative absorbed dose sensitivity was highly dependent on both readout mode and integration time of the OSL signal. For CW-OSL signals containing only the blue emission band, S{sub rel} was between 0.85 and 0.94 for 1 s readouts and between 0.82 and 0.93 for 10 s readouts. Similarly, for P-OSL readouts containing only the blue emission band S{sub rel} ranged from 0.86 to 0.91, and 0.82 to 0.93 for 1 s and 10 s readouts, respectively. For OSLD signals containing only the UV emission band, S{sub rel} ranged from 1.00 to 1.46, and 0.97 to 1.30 for P-OSL readouts of 1 s and 10 s, respectively. Conclusion: For measurements of absorbed dose using Al{sub 2}O{sub 3}:C OSLDs in therapeutic proton beams, dependence on beam quality was smallest for readout protocols that selected the blue emission band with small integration times. DA Granville received financial support from the Natural Sciences and Engineering Research Council of

  7. WE-D-17A-06: Optically Stimulated Luminescence Detectors as ‘LET-Meters’ in Proton Beams

    SciTech Connect

    Granville, D; Sahoo, N; Sawakuchi, GO

    Purpose: To demonstrate and evaluate the potential of optically stimulated luminescence (OSL) detectors (OSLDs) for measurements of linear energy transfer (LET) in therapeutic proton beams. Methods: Batches of Al2O2:C OSLDs were irradiated with an absorbed dose of 0.2 Gy in un-modulated proton beams of varying LET (0.67 keV/μm to 2.58 keV/μm). The OSLDs were read using continuous wave (CW-OSL) and pulsed (P-OSL) stimulation modes. We parameterized and calibrated three characteristics of the OSL signals as functions of LET: CW-OSL curve shape, P-OSL curve shape and the ratio of the two OSL emission band intensities (ultraviolet/blue ratio). Calibration curves were createdmore » for each of these characteristics to describe their behaviors as functions of LET. The true LET values were determined using a validated Monte Carlo model of the proton therapy nozzle used to irradiate the OSLDs. We then irradiated batches of OSLDs with an absorbed dose of 0.2 Gy at various depths in two modulated proton beams (140 MeV, 4 cm wide spread-out Bragg peak (SOBP) and 250 MeV, 10 cm wide SOBP). The LET values were calculated using the OSL response and the calibration curves. Finally, measured LET values were compared to the true values determined using Monte Carlo simulations. Results: The CW-OSL curve shape, P-OSL curve shape and the ultraviolet/blue-ratio provided proton LET estimates within 12.4%, 5.7% and 30.9% of the true values, respectively. Conclusion: We have demonstrated that LET can be measured within 5.7% using Al2O3:C OSLDs in the therapeutic proton beams used in this investigation. From a single OSLD readout, it is possible to measure both the absorbed dose and LET. This has potential future applications in proton therapy quality assurance, particularly for treatment plans based on optimization of LET distributions. This research was partially supported by the Natural Sciences and Engineering Research Council of Canada.« less

  8. WellnessRules: A Web 3.0 Case Study in RuleML-Based Prolog-N3 Profile Interoperation

    NASA Astrophysics Data System (ADS)

    Boley, Harold; Osmun, Taylor Michael; Craig, Benjamin Larry

    An interoperation study, WellnessRules, is described, where rules about wellness opportunities are created by participants in rule languages such as Prolog and N3, and translated within a wellness community using RuleML/XML. The wellness rules are centered around participants, as profiles, encoding knowledge about their activities conditional on the season, the time-of-day, the weather, etc. This distributed knowledge base extends FOAF profiles with a vocabulary and rules about wellness group networking. The communication between participants is organized through Rule Responder, permitting wellness-profile translation and distributed querying across engines. WellnessRules interoperates between rules and queries in the relational (Datalog) paradigm of the pure-Prolog subset of POSL and in the frame (F-logic) paradigm of N3. An evaluation of Rule Responder instantiated for WellnessRules revealed acceptable Web response times.

  9. The response of thermally and optically stimulated luminescence from Al2O3:C to high-energy heavy charged particles

    NASA Technical Reports Server (NTRS)

    Gaza, R.; Yukihara, E. G.; McKeever, S. W. S.

    2004-01-01

    The thermoluminescence (TL) and optically stimulated luminescence (OSL) response of Al2O3 dosimeters to high-energy heavy charged particles (HCP) has been studied using the heavy ion medical accelerator at Chiba, Japan. The samples were Al2O3 single-crystal chips, of the type usually known as TLD-500, and Luxel(TM) dosimeters (Al2O3:C powder in plastic) from Landauer Inc. The samples were exposed to 4He (150 MeV/u), 12C (400 MeV/u), 28Si (490 MeV/us) and 56Fe (500 MeV/u) ions, with linear energy transfer values covering the range from 2.26 to 189 keV/micrometers in water and doses from 1 to 100 mGy (to water). A 90Sr/90Y beta source, calibrated against a 60Co secondary standard, was used for calibration purposes. For OSL, we used both continuous-wave OSL measurements (CW-OSL, using green light stimulation at 525 nm) and pulsed OSL measurements (POSL, using 532 nm stimulation from a Nd:YAG Q-switched laser). The efficiencies (eta HCP, gamma) of the different HCPs at producing OSL or TL were observed to depend not only upon the linear energy transfer (LET) of the HCP, but also upon the sample type (single crystal chip or Luxel(TM)) and the luminescence method used to define the signal--i.e. TL, CW-OSL initial intensity, CW-OSL total area, or POSL. Observed changes in shape of the decay curve lead to potential methods for extracting LET information of unknown radiation fields. A discussion of the results is given, including the potential use of OSL from Al2O3 in the areas of space radiation dosimetry and radiation oncology. c2004 Elsevier Ltd. All rights reserved.

  10. The response of thermally and optically stimulated luminescence from Al2O3:C to high-energy heavy charged particles.

    PubMed

    Gaza, R; Yukihara, E G; McKeever, S W S

    2004-01-01

    The thermoluminescence (TL) and optically stimulated luminescence (OSL) response of Al2O3 dosimeters to high-energy heavy charged particles (HCP) has been studied using the heavy ion medical accelerator at Chiba, Japan. The samples were Al2O3 single-crystal chips, of the type usually known as TLD-500, and Luxel(TM) dosimeters (Al2O3:C powder in plastic) from Landauer Inc. The samples were exposed to 4He (150 MeV/u), 12C (400 MeV/u), 28Si (490 MeV/us) and 56Fe (500 MeV/u) ions, with linear energy transfer values covering the range from 2.26 to 189 keV/micrometers in water and doses from 1 to 100 mGy (to water). A 90Sr/90Y beta source, calibrated against a 60Co secondary standard, was used for calibration purposes. For OSL, we used both continuous-wave OSL measurements (CW-OSL, using green light stimulation at 525 nm) and pulsed OSL measurements (POSL, using 532 nm stimulation from a Nd:YAG Q-switched laser). The efficiencies (eta HCP, gamma) of the different HCPs at producing OSL or TL were observed to depend not only upon the linear energy transfer (LET) of the HCP, but also upon the sample type (single crystal chip or Luxel(TM)) and the luminescence method used to define the signal--i.e. TL, CW-OSL initial intensity, CW-OSL total area, or POSL. Observed changes in shape of the decay curve lead to potential methods for extracting LET information of unknown radiation fields. A discussion of the results is given, including the potential use of OSL from Al2O3 in the areas of space radiation dosimetry and radiation oncology. c2004 Elsevier Ltd. All rights reserved.

  11. Landform evolution modeling of fine-grained sedimentation on alluvial fans on Mars and Earth

    NASA Astrophysics Data System (ADS)

    Morgan, A. M.; Howard, A. D.; Moore, J. M.; Swander, Z. J.; Fink, D.; Korup, O.; Hesse, P. P.; Singh, T.; Srivastava, P.

    2017-12-01

    Reconstructing how rivers respond to changes in runoff or sediment supply by incising or aggrading has been pivotal in gauging the role of the Indian Summer Monsoon (ISM) as a geomorphic driver in the Himalayas. Here we present new data on how the fluvial systems of the Lesser Himalaya of India has responded to late Quaternary climate change. Our study is based on new chronological data for fluvial aggradation and incision from the Donga alluvial fan and several reaches of the upper Alaknanda River, as well as a meta-analysis of previous work. Fluvial sediments in the Himalayas in general, and quartz from the region in particular, have been previously noted for a number of unsuitable OSL properties including large recuperation and the existence of unremovable feldspar signals, leading to controversial discussions with regard to the reliability of existing OSL chronologies in this region. In order to improve the applicability and validity of OSL in the Lesser Himalaya, we have tested and applied pulsed OSL signals (POSL) to quartz grains from alluvial terrace and fan sediments, and propose a new chronology of regional fluvial aggradation. For previously dated terraces and alluvial fan sections, our POSL ages are systematically older than previously reported OSL ages. These results suggest periods of aggradation in the Alaknanda and Dehradun Valleys mainly between 20 and 50 ka. This most likely reflects decreased stream power during periods of weakened monsoon. The concentration of in-situ cosmogenic beryllium-10 from fluvial bedrock surfaces was also used to infer bedrock surface exposure ages, which should inform about episodes of active fluvial erosion. Resulting exposure ages span between 1.3 and 9.0 ka, suggesting that strath terraces were exposed relatively recently, and incision was dominant through most of the Holocene. In combination, our results support a precipitation-driven climatic control on fluvial dynamics, which regulates the balance between stream

  12. Transitioning to Intel-based Linux Servers in the Payload Operations Integration Center

    NASA Technical Reports Server (NTRS)

    Guillebeau, P. L.

    2004-01-01

    The MSFC Payload Operations Integration Center (POIC) is the focal point for International Space Station (ISS) payload operations. The POIC contains the facilities, hardware, software and communication interface necessary to support payload operations. ISS ground system support for processing and display of real-time spacecraft and telemetry and command data has been operational for several years. The hardware components were reaching end of life and vendor costs were increasing while ISS budgets were becoming severely constrained. Therefore it has been necessary to migrate the Unix portions of our ground systems to commodity priced Intel-based Linux servers. hardware architecture including networks, data storage, and highly available resources. This paper will concentrate on the Linux migration implementation for the software portion of our ground system. The migration began with 3.5 million lines of code running on Unix platforms with separate servers for telemetry, command, Payload information management systems, web, system control, remote server interface and databases. The Intel-based system is scheduled to be available for initial operational use by August 2004 The overall migration to Intel-based Linux servers in the control center involves changes to the This paper will address the Linux migration study approach including the proof of concept, criticality of customer buy-in and importance of beginning with POSlX compliant code. It will focus on the development approach explaining the software lifecycle. Other aspects of development will be covered including phased implementation, interim milestones and metrics measurements and reporting mechanisms. This paper will also address the testing approach covering all levels of testing including development, development integration, IV&V, user beta testing and acceptance testing. Test results including performance numbers compared with Unix servers will be included. need for a smooth transition while maintaining

  13. Luminescence and Radiocarbon dating of roman time harbour sediments from Cologne - A comparison of different methods

    NASA Astrophysics Data System (ADS)

    Lauer, Tobias; Frechen, Manfred; Fuchs, Magret C.; Trier, Marcus; Tsukamoto, Sumiko

    2010-05-01

    Optically stimulated luminescence (OSL) dating was applied to fluvial and colluvial deposits which were taken from a roman time harbour basin in Cologne. Hence, independent age control was given by roman artefacts (coins, bricks) of known age and by three radiocarbon data. For one sample (well sorted fluvial sand), a single aliquot regenerative (SAR) protocol was applied to coarse grain quartz. A large number of equivalent doses (80) were collected and after De-measurements, different statistical approaches were tested. The results show, that calculating the age by using the Mean or Median of all accepted De-values yields OSL ages of 3.5 ± 0.3 ka and 2.8 ± 0.3 ka, respectively, what would be significantly too old. The application of the Leading Edge Method (Lepper & McKeever 2002), the statistical approach after Fuchs & Lang (2001) or the Minimum Age Method (MAM3) after Galbraith et al. (1999) yield OSL age estimates of 2.0 ± 0.1 ka, 2.1 ± 0.1 ka and 1.7 ± 0.6 ka, respectively. Those ages fit very well to the 14C-ages and are in better agreement with the known archaeological background. For the colluvial sample, the quartz OSL signal was effected by feldspar impurities. For this sample, different methodological approaches were tested to see which one has the best potential to minimize the feldspar contribution. Therefore the post-IR blue stimulated quartz luminescence was recorded. The quartz signal was measured using continuous wave (CW) and pulsed OSL (POSL). For the CW measurements, it was tested if a prior IR-bleach @ 50°C or @ 225°C has better potential for minimizing the feldspar signal. In this case, an IR-bleach @ 225°C (Buylaert et al. in press) was the most effective way to obtain a higher purity of the quartz OSL signal. Buylaert, J.P., Murray, A.S., Thomsen, K.J., Jain, M.: The effect of preheating on the IRSL signal from feldspar. In press. - Radiat. Meas., special issue, LED08. Fuchs, M. & Lang, A. (2001): OSL dating of coarse-grain fluvial