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  1. Building 9401-2 Plating Shop Surveillance and Maintenance Plan

    SciTech Connect

    1999-05-01

    This document provides a plan for implementing surveillance and maintenance (S and M) activities to ensure that Building 9401-2 Plating Shop is maintained in a cost effective and environmentally secure configuration until subsequent closure during the final disposition phase of decommissioning. U.S. Department of Energy (DOE) G430.1A-2, Surveillance and Maintenance During Facility Disposition (1997), was used as guidance in the development of this plan. The S and M Plan incorporates DOE O 430.1A, Life Cycle Asset Management (LCAM) (1998a) direction to provide for conducting surveillance and maintenance activities required to maintain the facility and remaining hazardous and radioactive materials, wastes, and contamination in a stable and known condition pending facility disposition. Recommendations in the S and M plan have been made that may not be requirement-based but would reduce the cost and frequency of surveillance and maintenance activities. During the course of S and M activities, the facility's condition may change so as to present an immediate or developing hazard or unsatisfactory condition. Corrective action should be coordinated with the appropriate support organizations using the requirements and guidance stated in procedure Y10-202, Rev. 1, Integrated Safety Management Program, (Lockheed Martin Energy Systems, Inc. (LMES), 1998a) implemented at the Oak Ridge Y-12 Plant and the methodology of the Nuclear Operations Conduct of Operations Manual (LMES, 1999) for the Depleted Uranium Operations (DUO) organization. The key S and M objectives applicable to the Plating Shop are to: Ensure adequate containment of remaining residual material in exhaust stacks and outside process piping, stored chemicals awaiting offsite shipment, and items located in the Radioactive Material Area (RMA); Provide access control into the facility and physical safety to S and M personnel; Maintain the facility in a manner that will protect the public, the environment, and the S

  2. Determination of anisotropy in impact toughness of aluminium alloy 2024 T3 plate

    NASA Astrophysics Data System (ADS)

    Siddiqui, M. H.; Hashmi, F.; Junaid, A.

    The research was aimed to quantify the existence of anisotropy in fracture toughness of aluminium alloy 2024 T3 plate (used in aircraft structural members). It was further needed to establish the direction in which the fracture toughness of aluminium alloy 2024 T3 plate is maximum and minimum. This could help ascertain the structural integrity of aircraft structural components; also while designing new components, the knowledge of variation in toughness with respect to direction helps in economizing dead weight of the aircraft. In this research, pursued at the College of Aeronautical Engineering, the anisotropy in toughness of aluminium alloy 2024 T3 plate was analysed using the Charpy V-notch impact toughness test. The effect of specimen orientation on the impact toughness values of the alloy was investigated and compared with known results to verify the reliability of the work and to ascertain the extent of anisotropy in fracture toughness of the said alloy. Charpy impact tests were carried out on ASTM E 23 standard specimens machined at a reference laboratory at room temperature (23° C +/- 2° C). Four different specimen orientations analysed for the purpose of this study were L-S, L-T, T-S and T-L directions. Subsequently, the results obtained at the research centre were then analysed and correlated with morphology of microstructure of the material to establish the reliability of the experimental results. Moreover, an analysis was also done to cater for the possible errors that could affect the fracture toughness values obtained from experimental results. It was concluded that the T-S orientation of the plate had maximum toughness, whereas, minimum toughness was observed in L-T direction.

  3. The Levitation Characteristics of MGB2 Plates on Tracks of Permanent Magnets

    NASA Astrophysics Data System (ADS)

    Perini, E.; Bassani, E.; Giunchi, G.

    2010-04-01

    The bulk MgB2 can be manufactured in large plates by an innovative process: the reactive liquid Mg infiltration (Mg-RLI). According to this process it is possible to produce, even at lab scale, plates of 10÷20 cm in lateral dimensions. The superconducting material resulting is very dense and, even if it is in polycrystalline form, it levitates with respect to Permanent Magnets (PM), like the textured YBCO samples, up to 35 K. In order to control the levitation forces and stiffnesses of an MgB2 plate (10×10×1 cm3) moving with respect to a track of PM's (NdFeB bars arranged in 4 lines according to an Halbach disposition and separated by Iron flux concentrators), we have used an instrumented Cryogenic Levitation Apparatus (CLA). We have studied different kind of movements of the PM's track with respect to the MgB2 plate. First, we consider the vertical movement, assumed z direction, which describes the properly levitation characteristics. Secondly, we consider two kinds of lateral movements of the track, assumed x direction, with the long size of the magnets either perpendicular or parallel to the movement direction. The resulting configurations simulate the main movements that a superconducting levitating vehicle will do in a real track, either of axial or of guidance type. The levitation axial forces, measured in Field Cooling or Zero Field Cooling conditions, indicate that at the distance between superconducting plate and PM's of 4 mm it is possible to have an overall levitating pressure of 7 N/cm2.

  4. Reflection polarizers for the vacuum ultraviolet using Al + MgF2 mirrors and an MgF2 plate

    NASA Technical Reports Server (NTRS)

    Hass, G.; Hunter, W. R.

    1978-01-01

    Consideration is given to the design and operation of a three-mirror reflecting polarizer where one of the reflecting surfaces is an MgF2 plate, the other surfaces are Al + MgF2 coatings, and one reflection occurs at or near the true Brewster angle. It is found that the polarizer is most efficient in the 1200-2000 A wavelength region, and that by optimum selection of the angle of incidence on the MgF2 plate, polarization values of 100 and over are yielded from 900 to 3000 A. The polarizer may be used at wavelengths as short as 500 A, although it is observed that at such wavelengths the polarization value decreases to about 10. It is noted that all reflecting polarizers operating in the vacuum ultraviolet wavelength may manifest changing characteristics as their mirrors become contaminated, and that polarization must therefore be occasionally remeasured.

  5. Simulation of solidly mounted plate wave resonator with wide bandwidth using 0-th shear horizontal mode in LiNbO3 plate

    NASA Astrophysics Data System (ADS)

    Kadota, Michio; Tanaka, Shuji

    2015-07-01

    A cognitive radio system using a vacant frequency band of digital TV channels (TV white space) requires a tunable filter with wide tunable ranges of center frequency and bandwidth. An ultra-wideband resonator is a key device to implement the tunable filter, because the tunable range is limited by the bandwidth (BW) of the resonators. A 0-th shear horizontal (SH0) mode plate wave resonator using an ultra-thin LiNbO3 plate is known to have a large electromechanical coupling factor, i.e., a large BW, but the structural fragility of the ultra-thin LiNbO3 plate is problematic. In this study, the feasibility of solidly mounted resonator type SH0 mode plate wave resonator was investigated systematically by finite element method simulation. The design parameters including the Euler angle, thickness of a LiNbO3 plate, and the material and thickness of an interdigital transducer were optimized. With the best design, a BW as wide as 26% is obtained.

  6. Hardness and microstructural response to thermal annealing of irradiated ASTM A533B class 1 plate steel

    SciTech Connect

    Reinhart, D.E.; Kumar, A.S.; Gelles, D.S.; Hamilton, M.L.; Rosinski, S.T.

    1999-10-01

    Hardness measurements were used to determine the post-irradiation annealing response of A533B class 1 plate steel irradiated to a fluence of 1 {times} 10{sup 19} n/cm{sup 2} (E > 1 MeV) at 150 C. Rockwell hardness measurements indicated that the material had hardened by 6.6 points on the B scale after irradiation. The irradiation induced hardness increase was associated with a decrease in upper shelf energy from 63.4 J to 5-1.8 J and a temperature shift in the Charpy curve at the 41 J level from 115 C to 215 C. Specimens were annealed after irradiation at temperatures of 343 C (650 F), 399 C (750 F), and 454 C (850 F) for durations of up to one week (168 h). Hardness measurements were made to chart recovery of hardness as a function of time and temperature. Specimens annealed at the highest temperature 454 C recovered the fastest, fully recovering within 144 h. Specimens annealed at 399 C recovered completely within 168 h. Specimens annealed at the lowest temperature, 343 C recovered only {approximately}70% after 168 h of annealing. After neutron irradiation, a new feature of black spot damage was found to be superimposed on the unirradiated microstructure. The density of black spots was found to vary from 2.3 {times} 10{sup 15}/cm{sup 3} to 1.1 {times} 10{sup 16}/cm{sup 3} with an average diameter of 2.85 nm. Following annealing at 454 C for 24 h the black spot damage was completely annealed out. It was concluded that the black spot damage was responsible for 70% of the irradiation-induced hardness.

  7. Ultra-wideband ladder filters using zero-th shear mode plate wave in ultrathin LiNbO3 plate with apodized interdigital transducers

    NASA Astrophysics Data System (ADS)

    Kadota, Michio; Tanaka, Shuji

    2016-07-01

    There are two kinds of plate waves propagating in a thin plate, Lamb and shear horizontal (SH) waves. The former has a velocity higher than 15,000 m/s when the plate is very thin. On the contrary, 0th SH (SH0) mode plate wave in an ultrathin LiNbO3 plate has an electro-mechanical coupling factor larger than 50%. Authors fabricated an ultra-wideband T-type ladder filter with a relative bandwidth (BW) of 41% using the SH0 mode plate wave. Although the BW of the filter fully covers the digital TV band in Japan, it does not have sufficient margin at the lower and higher end of BW. Besides, periodic small ripples due to transverse mode in pass-band of the filter were observed. In this study π-type ladder filters were fabricated by changing the pitch ratio of interdigital transducer (IDT) of parallel and series arm resonators (PR(IDT)) to control the BW, and by apodizing IDTs to improve the periodic small ripples due to transverse mode. Ultra-wideband filters without periodic small transverse mode with ultrawide bandwidth from 41 to 49% were fabricated. The BWs fully cover ultrawide digital television bands in Japan and U.S.A. These filters with an ultrawide BW and a steep characteristic show the possibility to be applied to a reported cognitive radio system and other communication systems requiring an ultrawide BW.

  8. Investigation of the Contact Resistance between Ti/TiN and Ru in Metal-1/Plate Contacts of Ruthenium Insulator Silicon Capacitor

    NASA Astrophysics Data System (ADS)

    Yun, Ju Young; Kim, Byung Hee; Seo, Jung Hun; Lee, Jong Myeong; Kang, Sang Bom; Choi, Gil Heyun; Chung, U In; Moon, Joo Tae

    2003-04-01

    The contact resistance between Ti/TiN and a Ru electrode in metal-1/plate contacts of ruthenium insulator silicon (RIS) capacitor is investigated. When physical vapor deposition (PVD) Ti/TiN was used as a barrier metal for the metal contact process, a high contact resistance of more than 5000 Ω/contact was obtained due to the oxidation of Ti by the residual oxygen in Ru electrode. On the other hand, with a plasma enhanced chemical vapor deposition (PECVD) Ti/CVD TiN barrier metal, oxidation of Ti was not observed and subsequently a low contact resistance of 15 Ω/contact was obtained. The absence of Ti oxidation with PECVD Ti/CVD TiN can be explained by the reduction of oxygen in the Ru electrode due to the H2 plasma environment in the PECVD-Ti process.

  9. Isolation and characterization of two sequence-specific endonucleases from Anabaena variabilis.

    PubMed Central

    Murray, K; Hughes, S G; Brown, J S; Bruce, S A

    1976-01-01

    Two endonucleases, AvaI and AvaII, were isolated from Anabaena variabilis on the basis of their ability to make a limited number of breaks at specific points in bacteriophage lambda DNA. Neither enzyme has cofactor requirements beyond Mg2+. Endonuclease AvaI makes eight breaks in the phage lambda chromosome at which the 5'-terminal sequence is pPy-C-G-N. AvaII endonuclease cuts phage lambda DNA more extensively, yielding fragments with the 5'-terminal sequence G-T-C-N or G-A-C-N. Neither enzyme generates cohesive ends. Images PLATE 1 PLATE 2 PLATE 3 PLATE 4 PMID:11780

  10. Nucleotide `maps' of digests of deoxyribonucleic acid

    PubMed Central

    Murray, K.

    1970-01-01

    Various digests of 32P-labelled DNA were examined by two-dimensional ionophoresis on cellulose acetate and DEAE-cellulose paper. The products from digestion with pancreatic deoxyribonuclease and Neurospora crassa endonuclease were qualitatively closely similar, but very complex, and were used to investigate the mapping behaviour of nucleotides in various ionophoretic systems. Ionophoresis on DEAE-cellulose paper in triethylamine carbonate, pH 9.7, followed by ionophoresis in the second dimension at pH1.9 gave high resolution of nucleotides in very complex mixtures and permitted the fractionation of larger quantities than is possible on cellulose acetate. High resolution of nucleotides in compact spots was obtained with two-dimensional ionophoresis on cellulose acetate and AE-cellulose paper, a system that is a useful supplement to those based on DEAE-cellulose paper. ImagesPLATE 7PLATE 1PLATE 2PLATE 3PLATE 4PLATE 5PLATE 6 PMID:5476726

  11. Nucleotide sequence analysis with polynucleotide kinase and nucleotide `mapping' methods. 5′-Terminal sequence of deoxyribonucleic acid from bacteriophages λ and 424

    PubMed Central

    Murray, Kenneth

    1973-01-01

    The polynucleotide kinase reaction was used in analyses of complex mixtures of oligodeoxynucleotides which were fractionated by various two-dimensional nucleotide `mapping' procedures. Parallel ionophoretic analyses on DEAE-cellulose paper, pH2, and AE-cellulose paper, pH3.5, of venom phosphodiesterase partial digests of 5′-terminally labelled oligonucleotides enabled the sequence of the nucleotides to be deduced uniquely. A `diagonal ionophoresis' method has been used with mixtures of nucleotides. Application of these methods to 5′-terminally labelled DNA from bacteriophage λ gave the terminal sequences pA-G-G-T-C-G and pG-G-G-C-G. Identical 5′-terminal sequences were found with DNA from bacteriophage 424. ImagesPLATE 5PLATE 1PLATE 2PLATE 3PLATE 4 PMID:4352720

  12. Inward spread of activation in vertebrate muscle fibres

    PubMed Central

    González-Serratos, H.

    1971-01-01

    1. A method for detecting the activation of individual myofibrils or groups of myofibrils within an isolated muscle fibre is described. It consists in making all the myofibrils wavy by setting the fibre in gelatine and compressing it longitudinally; active shortening of myofibrils can then be recognized by the straightening out of the waves. 2. The time course of this straightening during a twitch was found by high-speed ciné micrography. 3. There is a delay of activation between the superficial and central myofibrils, from which the velocity of inward spread of activation can be found. 4. This velocity has a Q10 of 2, and is about 7 cm/sec at 20° C. The mechanism of the inward spread of activation is discussed. 5. On relaxation the waves reappear, showing that there is a spontaneous elongation of the myofibrils. ImagesPlate 1Plate 2Plate 3Plate 4 PMID:5557071

  13. Immunohistochemical localization of protein components of catecholamine storage vesicles

    PubMed Central

    Geffen, L. B.; Livett, B. G.; Rush, R. A.

    1969-01-01

    transported somatofugally in the axon. ImagesText-fig. 2Text-fig. 3Plate 1Plate 2Plate 3Plate 4 PMID:4980932

  14. Ovarian tumors of the hen.

    PubMed Central

    Fredrickson, T N

    1987-01-01

    Present available information regarding ovarian tumors in hens is incomplete in most aspects, and this lack of knowledge hampers use of hens as models for study of ovarian cancer. A study of 466 hens ranging from 2 to 7 years of age and covering a period of more than 3 years has provided much needed information relative to reproductive tract neoplasia. On the basis of this study, it is apparent that hens have a high rate of ovarian tumors, but that such tumors are uncommon in hens less than 2 years of age. Adenocarcinomas with a high degree of morphologic variability are the most common ovarian tumors in hens. Hormonal imbalance does not appear to be a factor in the development of these adenocarcinomas. Steroidogenic and morphologically distinctive granulosa cell tumors originating from follicles in atrophic ovaries represent another common ovarian tumor type. Unique to the hen are oviductal adenocarcinomas. These tumors arise from the albumin-secreting glands of the oviduct, occur with relatively high frequency, and must be differentiated from ovarian adenocarcinomas. Images PLATE 1. PLATE 2. PLATE 3. PLATE 4. PLATE 5. PLATE 6. PLATE 7. PLATE 8. PLATE 9. PLATE 10. PLATE 11. PLATE 12. PLATE 13. PLATE 14. PLATE 15. PLATE 16. PLATE 17. PLATE 18. PLATE 19. PLATE 20. PLATE 21. PLATE 22. PLATE 23. PLATE 24. PLATE 25. PMID:3665870

  15. Some factors affecting the production, by cultured baby-hamster kidney cells, of BHK glycoprotein I which cross-reacts immunologically with Tamm-Horsfall glycoprotein.

    PubMed Central

    Bloomfield, F J; Dunstan, D R; Foster, C L; Serafini-Cessi, F; Marshall, R D

    1977-01-01

    Cultured baby-hamster kidney cells (BHK-21/C13), which are adapted to grow in suspension (strain 2P), roduce a glycoprotein, termed BHK glycoprotein I, which cross-reacts immunologically with hamster urinary (Tamm-Horsfall glycoprotein. BHK glycoprotein I was isolated in an electrophoretically (sodium dodecyl sulphate/polyacrylamide gel) homogeneous form by application of affinity chromatography to the medium in which cells had been cultured. Insolubilized anti-(Tamm-Horsfall glycoprotein immunoglobulin G) was used as the adsorbent. The amount of BHK glycoprotein I associated with the cultured cells was found by both radioimmunoassay and immunofluorescence to be related to the amount of Ca2+ in the medium and to the particular stage of the cell cycle. 5'-Nucleotidase was also shed by the cells into the culture medium in amounts related to the stage of the cell cycle. The turnover of hamster Tamm-Horsfall glycoprotein in vivo appeared to be considerably more rapid than can be accounted for by cell turnover. Hamster Tamm-Horsfall glycoprotein was shown to be ineffective in inhibiting agglutination of chicken erythrocytes caused by influenza virus. Images PLATE 1 PLATE 2 PLATE 3 PLATE 4 PMID:328011

  16. Pathology Working Group review of selected upper respiratory tract lesions in rats and mice.

    PubMed Central

    Maronpot, R R

    1990-01-01

    The collected comments and pathologic diagnoses of several pathologists are summarized for 18 cases in which lesions were induced in the upper respiratory tract of rats and mice. Specific neoplastic and nonneoplastic lesions of the nose and trachea are described and discussed, and opinions regarding pathogenesis and biologic significance of the lesions are presented. The anatomic and pathophysiologic complexities of the rodent nose in relation to lesion development following inhalation or systemic exposure to xenobiotics are important considerations in the genesis of pathologic changes in this organ. Images PLATE 1. PLATE 2. PLATE 3. PLATE 4. PLATE 5. PLATE 6. PLATE 7. PLATE 8. PLATE 9. PLATE 10. PLATE 11. PLATE 12. PLATE 13. PLATE 14. PLATE 15. PLATE 16. PLATE 17 PLATE 18 PLATE 19 PLATE 20. PLATE 21. PLATE 22. PLATE 23. PLATE 24. PLATE 25. PLATE 26. PLATE 27. PLATE 28. PLATE 29. PLATE 30. PLATE 31. PLATE 32. PLATE 33. PLATE 34. PLATE 35. PLATE 36. PLATE 37. PLATE 38. PLATE 39. PLATE 40. PLATE 41. PLATE 42. PLATE 43. PLATE 44. PLATE 45. PLATE 46. PLATE 47. PLATE 48. PLATE 49. PLATE 50. PLATE 51. PLATE 52. PLATE 53. PMID:2384066

  17. Nonneoplastic nasal lesions in rats and mice.

    PubMed Central

    Monticello, T M; Morgan, K T; Uraih, L

    1990-01-01

    Rodents are commonly used for inhalation toxicology studies, but until recently the nasal passages have often been overlooked or only superficially examined. The rodent nose is a complex organ in which toxicant-induced lesions may vary, depending on the test compound. A working knowledge of rodent nasal anatomy and histology is essential for the proper evaluation of these responses. Lack of a systematic approach for examining rodent nasal tissue has led to a paucity of information regarding nonneoplastic lesions in the rodent nose. Therefore, slides from the National Toxicology Program (NTP) and the Chemical Industry Institute of Toxicology (CIIT) were examined, and the literature was reviewed to assemble the spectrum of nonneoplastic rodent nasal pathology. Presented are lesions associated with the various types of epithelia lining the rodent nasal cavity plus lesions involving accessory nasal structures. Even though there are anatomic and physiologic differences between the rodent and human nose, both rats and mice provide valuable animal models for the study of nasal epithelial toxicity, following administration of chemical compounds. Images PLATE 1. PLATE 2. PLATE 3. PLATE 4. PLATE 5. PLATE 6. PLATE 7. PLATE 8. PLATE 9. PLATE 10. PLATE 11. PLATE 12. PLATE 13. PLATE 14. PLATE 15. PLATE 16. PLATE 17. PLATE 18. PLATE 19. PLATE 20. PLATE 21. PLATE 22. PLATE 23. PLATE 24. PLATE 25. PLATE 26. PLATE 27. PLATE 28. PLATE 29. PLATE 30. PLATE 31. PLATE 32. PLATE 33. PLATE 34. PLATE 35. PLATE 36. PLATE 37. PLATE 38. PMID:2200665

  18. Electrically induced release of acetylcholine from denervated Schwann cells

    PubMed Central

    Dennis, M. J.; Miledi, R.

    1974-01-01

    1. Focal electrical stimulation of Schwann cells at the end-plates of denervated frog muscles elicited slow depolarizations of up to 30 mV in the muscle fibres. This response is referred to as a Schwann-cell end-plate potential (Schwann-e.p.p.). 2. Repeated stimulation sometimes evoked further Schwann-e.p.p.s, but they were never sustained for more than 30 pulses. Successive e.p.p.s varied in amplitude and time course independently of the stimulus. 3. The Schwann-e.p.p.s were reversibly blocked by curare, suggesting that they result from a release of acetylcholine (ACh) by the Schwann cells. 4. ACh release by electrical stimulation did not seem to occur in quantal form and was not dependent on the presence of calcium ions in the external medium; nor was it blocked by tetrodotoxin. 5. Stimulation which caused release of ACh also resulted in extensive morphological disruption of the Schwann cells, as seen with both light and electron microscopy. 6. It is concluded that electrical stimulation of denervated Schwann cells causes break-down of the cell membrane and releases ACh, presumably in molecular form. ImagesPlate 1Plate 2Plate 3Plate 4Plate 5Plate 6Plate 7Plate 8Plate 9Plate 10 PMID:4545183

  19. Genetic dissection of the photoreceptor system in the compound eye of Drosophila melanogaster

    PubMed Central

    Stark, William S.; Walker, John A.; Harris, William A.

    1976-01-01

    1. Three mutations which eliminate specific types of photoreceptors in Drosophila were characterized. 2. Of the eight photoreceptors in each facet, two mutations delete the outer six (R 1-6). The third eliminates R 7, one of the two central photoreceptors. Double mutants can be constructed in which only photoreceptor R 8 is present. 3. The spectral sensitivities, photopigments, and behavioural properties of these mutants were investigated. 4. R 1-6 have two sensitivity peaks, near 350 and 470 nm. These receptors contain a rhodopsin with these absorption peaks. It interconverts with a metarhodopsin that absorbs around 570 nm. 5. R 7 is a U.V.-receptor, containing rhodopsin that absorbs around 370 nm and interconverts with a metarhodopsin which absorbs around 470 nm. 6. R 8 is a non-adapting blue-receptor with a third type of rhodopsin. 7. The properties of these photopigments explain the different sensitivities and spectral adaptation phenomena of the various photoreceptors. 8. All the photoreceptors have input into phototaxis. Spectral analysis of this behaviour provides evidence for integration of the input from the different photoreceptors. ImagesPlate 6Plate 1Plate 2Plate 3Plate 4Plate 5 PMID:16992509

  20. Localization by immunofluorescence and by light- and electron-microscopic immunoperoxidase techniques of Tamm–Horsfall glycoprotein in adult hamster kidney

    PubMed Central

    Sikri, Krishan L.; Foster, Charles L.; Bloomfield, Frederick J.; Marshall, R. Derek

    1979-01-01

    1. Tamm–Horsfall glycoprotein was isolated from hamster urine and antiserum against it was produced in rabbits. Immunoglobulin G was isolated from the antiserum. 2. Indirect methods of immunofluorescence staining were applied to kidney sections previously fixed by both perfusion and immersion methods. Tamm–Horsfall glycoprotein was identified associated with only the cells of the ascending limb of the loop of Henle and the distal convoluted tubule. Maculae densae were free of the glycoprotein. 3. Indirect immunoperoxidase procedures with light microscopy were applied to kidney sections. The results extended those found by immunofluorescence by showing that the glycoprotein is largely associated with the plasma membrane of the cells. Macula densa cells were shown to be free of the glycoprotein, although the luminal surface of the remaining cells in the transverse section of the nephron at that region was shown to contain it. 4. A variety of immuno-electron-microscopic techniques were applied to sections previously fixed in a number of ways. Providing periodate/lysine/paraformaldehyde was used as the fixative, the glycoprotein was often seen to be present not only on the luminal surface of the cells of the thick ascending limb of the loop of Henle and of the distal convoluted tubule, but also on the basal plasma membrane, including the infoldings. 5. It is generally accepted that the hyperosmolarity in the medulla of the kidney results from passage of Cl− ions with their accompanying Na+ ions across the single cell layer of the lumen of the thick ascending limb of the loop of Henle, a region of the nephron with relatively high impermeability to water. We suggest that Tamm–Horsfall glycoprotein operates as a barrier to decrease the passage of water molecules by trapping the latter at the membrane of the cells. Our hypothesis requires the glycoprotein on the basal plasma membrane also. ImagesFig. 1.PLATE 4PLATE 1PLATE 3PLATE 2PLATE 6PLATE 5 PMID:391220

  1. An "in-production" method for testing the sterility of infusion fluids.

    PubMed Central

    Rycroft, J. A.; Moon, D.

    1975-01-01

    The addition of dehydrated broth powder to a random selection of bottles from each batch of infusion fluids before sterilization, followed by incubation of the bottles after sterilization, provides a method of sterilty testing which possesses many advantages over the traditional method of culturing small samples from bottles after sterilization. Images Plate 1 Plate 3 Plate 2 PMID:1089707

  2. Changes in spectral reflexions from the iridophores of the neon tetra.

    PubMed Central

    Lythgoe, J N; Shand, J

    1982-01-01

    1. The iridescent stripe of the freshwater teleost, the neon tetra, changes from green in the daytime to violet-blue at night. 2. Spectral reflectance measurements were used to follow these colour changes. 3. Light causes a shift in reflectance to longer wavelengths in living fish and in isolated tissue from the lateral stripe. The change is reversed in darkness. 4. The spectral reflectance shifts to longer wavelengths when the fish is disturbed in darkness. No such colour changes were seen in fishes kept alive in 10(-4) M-reserpine. 5. Hypotonic Ringer solution causes a reflectance shift to longer wavelengths and hypertonic solution causes a shift to shorter wavelengths. 6. The iridescent reflexions from the lateral stripe which is continued across the iris originate from iridophores in the dermis. These iridophores contain regular stacks of broad, double-sided hexagonal plates that are about 10 nm thick. Each plate is contained within a pouch in the cytoplasm and is separated from its neighbour by approximately one quarter the wavelength of light. 7. A distinction is drawn between the physiologically active iridophores in the lateral stripe and iris that have broad hexagonal crystal plates which are very thin and the physiologically inactive iridophores that are also found in the iris, but in addition are found on the flanks below the lateral stripe, and on the head. These iridophores contain hexagonal crystals that are usually narrower than the active type, but are about 60-100 nm thick. Images Plate 1 Plate 2 Plate 3 Plate 4 Plate 5 PMID:7108777

  3. The primary inhibitor of plasmin in human plasma.

    PubMed Central

    Müllertz, S; Clemmensen, I

    1976-01-01

    A complex between plasmin and an inhibitor was isolated by affinity chromatography from urokinase-activated human plasma. The complex did not react with antibodies against any of the known proteinase inhibitors in plasma. A rabbit antiserum against the complex was produced. It contained antibodies agianst plasminogen+plasmin and an alpha2 protein. By crossed immunoelectrophoresis the alpha2 protein was shown to form a complex with plasmin, when generated by urokinase in plasma, and with purified plasmin. The alpha2 protein was eluted by Sephadex G-200 gel filtration with KD approx. 0.35, different from the other inhibitors of plasmin in plasma, and corresponding to an apparent relative molecular mass (Mr) of about 75000. By sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, the Mr of the complex was found to be approx. 130000. After reduction of the complex two main bands of protein were observed, with Mr, about 72000 and 66000, probably representing an acyl-enzyme complex of plasmin-light chain and inhibitor-heavy chain, and a plasmin-heavy chain. A weak band with Mr 9000 was possibly an inhibitor-light chain. The inhibitor was partially purified and used to titrate purified plasmin of known active-site concentration. The inhibitor bound plasmin rapidly and strongly. Assuming an equimolar combining ratio, the concentration of active inhibitor in normal human plasma was estimated to be 1.1 mumol/1. A fraction about 0.3 of the antigenic inhibitor protein appeared to be functionally inactive. In plasma, plasmin is primarily bound to the inhibitor. Only after its saturation does lysis of fibrinogen and fibrin occur and a complex between plasmin and alpha2 macroglobulin appear. Images PLATE 1 PLATE 2 PLATE 3 PLATE 4 PMID:137718

  4. Near-field radiative heat transfer between two parallel SiO{sub 2} plates with and without microcavities

    SciTech Connect

    Ijiro, T.; Yamada, N.

    2015-01-12

    Near-to-far-field radiative heat transfer between two macroscopic SiO{sub 2} plates—with and without microcavities—was observed using a highly precise and accurate optical gap-measurement method. The experiments, conducted near 300 K, measured heat transfer as a function of gap separation from 1.0 μm to 50 μm and also as a function of temperature differences between 4.1 and 19.5 K. The gap-dependent heat flux was in excellent agreement with theoretical predictions. Furthermore, the effects of microcavities on the plate surfaces were clearly observed and significant enhancement of near-field radiative heat transfer was confirmed between gold-coated microcavities with narrow vacuum separation.

  5. Mycoplasmas isolated from the respiratory tract of horses.

    PubMed Central

    Allam, N. M.; Lemcke, R. M.

    1975-01-01

    other four species were found in normal horses as well as those with respiratory disease, although three out of the four strains of M. equirhinis were from sick horses. Images Plate 2 Plate 5 Plate 3 Plate 1 Plate 4 PMID:807616

  6. Looking at proteins: representations, folding, packing, and design. Biophysical Society National Lecture, 1992.

    PubMed Central

    Richardson, J S; Richardson, D C; Tweedy, N B; Gernert, K M; Quinn, T P; Hecht, M H; Erickson, B W; Yan, Y; McClain, R D; Donlan, M E

    1992-01-01

    Looking at proteins is an active process of interpretation and selection, emphasizing some features and deleting others. Multiple representations are needed, for such purposes as showing motions or conveying both the chain connectivity and the three-dimensional shape simultaneously. In studying and comparing protein structures, ideas are suggested about the determinants of tertiary structure and of folding (e.g., that Greek key beta barrels may fold up two strands at a time). The design and synthesis of new proteins "from scratch" provides a route toward the experimental testing of such ideas. It has also been a fruitful new perspective from which to look at structures, requiring such things as statistics on very narrowly defined structural categories and explicit attention to "negative design" criteria that actively block unwanted alternatives (e.g., reverse topology of a helix bundle, or edge-to-edge aggregation of beta sheets). Recently, the field of protein design has produced a rather unexpected general result: apparently we do indeed know enough to successfully design proteins that fold into approximately correct structures, but not enough to design unique, native-like structures. The degree of order varies considerably, but even the best designed material shows multiple conformations by NMR, more similar to a "molten globule" folding intermediate than to a well ordered native tertiary structure. In response to this conclusion, we are now working on systems that test useful questions with approximate structures (such as determining which factors most influence the choice of helix-bundle topology) and also analyzing how natural proteins achieve unique core conformations (e.g., for side chains on the interior side of a beta sheet, illustrated in the kinemages). Images p1187-a PLATE 1 PLATE 2 PLATE 3 PLATE 4 PLATE 5 PLATE 6 PLATE 7 PLATE 8 PLATE 9 PLATE 10 PLATE 11 PLATE 12 PLATE 13 PLATE 14 PLATE 15 PLATE 16 PLATE 17 PLATE 18 PLATE 19 PLATE 20 PLATE 21 PLATE 22

  7. Characterization of the serum lipoproteins and their apoproteins in hypercholesterolaemic guinea pigs.

    PubMed Central

    Chapman, M J; Mills, G L

    1977-01-01

    1. Hypercholesterolaemia was induced in male guinea pigs after 6 days on a chow diet supplemented with 1.6% (w/w) cholesterol and 15% (w/w) corn oil. Both the VLD (very-low-density) and LD (low-density) lipoproteins were increased in cholesterol-fed animals, although the low concentrations of HD (high-density) lipoproteins remained essentially unchanged. LD lipoproteins of d 1.019-1.100 were the major class, accounting for 74% of the total substances of d less than 1.100. 2. Both VLD and LD lipoproteins exhibited alterations in their chemical composition, physical properties and apolipoprotein content. The VLD lipoproteins in cholesterolaemic animals were rich in cholesterol (25.9%), deficient in protein (4.9%) and exhibited electrophoretic mobility greater than that of beta-globulin; their average particle size (64.5 nm) was larger than that in controls (46.3 nm). The LD lipoproteins in animals fed on the experimental diet were also richer in cholesterol (53.1%) and of larger diameter (24.3 nm) than in the control group (41.1% and 21.4 nm respectively). 3. The apolipoprotein-B content of both VLD and LD lipoproteins was elevated in cholesterolaemic animals, particularly in the VLD class, where it represented 74.8% of the total protein moiety. 4. Apo-VLD lipoprotein exhibited an increase from 6 to 19% in its complement of tetramethylurea-soluble apolipoproteins with low electrophoretic mobility (relative mobility less than 0.29); this was primarily accounted for by apolipoproteins characterized by high arginine (7.2 and 6.4% respectively) and glutamic acid (20.1 and 20.0% respectively) contents. 5. By contrast, there was little change in the soluble apolipoproteins of LD lipoproteins in hypercholesterolaemic animals.6. These studies show the response of the guinea pig to dietary fat and cholesterol to be distinct from that elicited by similar stimuli in the rabbit, rat, pig and dog. Images PLATE 1 PLATE 2 PLATE 3 PLATE 4 PMID:588269

  8. Studies of the development of brain barrier systems to lipid insoluble molecules in fetal sheep.

    PubMed Central

    Dziegielewska, K M; Evans, C A; Malinowska, D H; Møllgård, K; Reynolds, J M; Reynolds, M L; Saunders, N R

    1979-01-01

    -brain barrier occurs via a transcellular route consisting of a system of tubulo-cisternal endoplasmic reticulum. Penetration via the choroid plexus appears to be the dominant route for penetration from blood into c.s.f. in the 60 day fetus. Images Plate 1 Plate 2 Plate 3 Plate 4 Plate 5 Plate 6 Plate 7 PMID:490348

  9. Ultra-wideband ladder filter using SH(0) plate wave in thin LiNbO(3) plate and its application to tunable filter.

    PubMed

    Kadota, Michio; Tanaka, Shuji

    2015-05-01

    A cognitive radio terminal using vacant frequency bands of digital TV (DTV) channels, i.e., TV white space, strongly requires a compact tunable filter covering a wide frequency range of the DTV band (470 to 710 MHz in Japan). In this study, a T-type ladder filter using ultra-wideband shear horizontal mode plate wave resonators was fabricated, and a low peak insertion loss of 0.8 dB and an ultra-large 6 dB bandwidth of 240 MHz (41%) were measured in the DTV band. In addition, bandpass filters with different center frequencies of 502 and 653 MHz at 6 dB attenuation were numerically synthesized based on the same T-type ladder filter in conjunction with band rejection filters with different frequencies. The results suggest that the combination of the wideband T-type ladder filter and the band rejection filters connected with variable capacitors enables a tunable filter with large tunability of frequency and bandwidth as well as large rejection at the adjacent channels of an available TV white space. PMID:25965686

  10. The effect orientation of features in reconstructed atom probe data on the resolution and measured composition of T1 plates in an A2198 aluminium alloy.

    PubMed

    Mullin, Maria A; Araullo-Peters, Vicente J; Gault, Baptiste; Cairney, Julie M

    2015-12-01

    Artefacts in atom probe tomography can impact the compositional analysis of microstructure in atom probe studies. To determine the integrity of information obtained, it is essential to understand how the positioning of features influences compositional analysis. By investigating the influence of feature orientation within atom probe data on measured composition in microstructural features within an AA2198 Al alloy, this study shows differences in the composition of T1 (Al2CuLi) plates that indicates imperfections in atom probe reconstructions. The data fits a model of an exponentially-modified Gaussian that scales with the difference in evaporation field between solutes and matrix. This information provides a guide for obtaining the most accurate information possible. PMID:25896290

  11. Excellent performances of energy harvester using cantilever driving double-clamped 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 plates and symmetric middle-stops

    NASA Astrophysics Data System (ADS)

    Zeng, Zhou; Ren, Bo; Xu, Qing; Lin, Di; Di, Wenning; Luo, Haosu; Wang, Dong

    2015-10-01

    We present a high performance nonlinear piezoelectric energy harvester constituted by a cantilever with symmetrically middle-stops and double-clamped piezoelectric plates based on piezoelectric single crystal 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3. Electrical properties of the device under different excitation frequencies, accelerations, and load resistances are studied systematically. Under a low acceleration of 3 m/s2 (0.3 g), a peak voltage of 26.2 V and a maximum normalized power of 25.6 mW/g2 were obtained across a matching impedance of 600 kΩ with favorable bandwidths. The low excitation acceleration and excellent performances indicate that the device can be a promising candidate for energy harvesting in low-power electronics and wireless sensors.

  12. Large self-biased and multi-peak magnetoelectric coupling in transducer of Pb(Zr,Ti)O3 plates and H-type magnetization-graded ferromagnetic fork

    NASA Astrophysics Data System (ADS)

    Shen, Yongchun; Ling, Zhihao; Lu, Caijiang

    2015-12-01

    This paper develops a self-biased magnetoelectric (ME) composite Metglas/H-type-FeNi/PZT (MHFP) of H-type magnetization-graded Metglas/H-type-FeNi fork and piezoelectric Pb(Zr,Ti)O3 (PZT) plate. By using the magnetization-graded magnetostrictive layer and symmetrical H-type structure, giant self-biased ME coupling and multi-peak phenomenon are observed. The zero-biased ME voltage coefficient of MHFP composite reaches ˜63.8 V/cm Oe, which is ˜37.5 times higher than that of traditional FeNi/PZT laminate. The output ME voltage has a good near linear relation with Hac and is determined to be ˜5.1 V/Oe and ˜10.6 mV/Oe at ˜65 kHz and 1 kHz, respectively. These indicate that the proposed composite show promising applications for ME transducers and high-sensitivity self-biased magnetic sensors.

  13. High-resolution transmission electron microscopy investigation of the face-centered cubic/hexagonal close-packed martensite transformation in Co-31.8 wt pct Ni alloy: Part 2. Plate intersections, extended defects, and nucleation mechanisms

    NASA Astrophysics Data System (ADS)

    Bray, D. W.; Howe, J. M.

    1996-11-01

    The face-centered cubic/hexagonal close-packed (fcc/hcp) martensite phase transformation in a Co-31.8 wt pct Ni alloy was studied by high-resolution transmission electron microscopy (HRTEM). The HRTEM was used to study the structure and properties of intersections between martensite plates and other defects observed in the alloy such as stacking fault tetrahedra (SFT) and Z-type defects. The HRTEM was also used to attempt to determine if various proposed mechanisms for the fcc/hcp martensite transformation were operating. There is evidence to suggest that the reflection mechanism proposed by Bollmann and the dipole mechanism proposed by Hirth are active in the fcc/hcp martensitic transformation, although the evidence is not completely certain in either case. Growth of the hcp phase by a four- or six-plane mechanism as proposed by Mahajan et al. is possible in theory but was not observed in this study. Transformation by previously proposed pole mechanisms was also not observed in this study, although evidence for a new type of pole mechanism was found. The formation of SFT along the fcc/hcp martensite interface was observed to occur by the cross-slip of Shockley partial dislocations out of the fcc/hcp interface onto conjugate fcc matrix planes, followed by further cross-slip to form the SFT, as previously observed for grain boundaries in fcc alloys.

  14. Identification of the immunoglobulin class active in the Rose Bengal plate test for bovine brucellosis

    PubMed Central

    Corbel, M. J.

    1972-01-01

    The antibodies active in the Rose Bengal plate test (RBPT) for bovine brucellosis have been studied. The results of fractionation experiments showed that RBPT activity was associated with fractions containing immunoglobulin of the IgG1 class; other immunoglobulin classes were inactive in this respect although active in other tests. These results were confirmed by inhibition tests with specific antisera and by elution of the antibody from agglutinated RBPT antigen. The major proportion of the serum complement-fixing activity was also present in the IgG1 fraction and it is suggested that the RBPT and CF reactions are probably mediated by the same antibodies. ImagesFig. 1Fig. 2Fig. 3Plate 2Plate 2 PMID:4630606

  15. Purification of the Thy-1 molecule, a major cell-surface glycoprotein of rat thymocytes.

    PubMed Central

    Letarte-Muirhead, M; Barclay, A N; Williams, A F

    1975-01-01

    The Thy-1-molecule, which was identified by its antigenic activities, has been purified from rat thymocytes. The purification involved preparation of crude membranes and solubilization in deoxycholate, followed by gel filtration and affinity chromatography on antibody or lectin columns. In all cases the purified molecule was a glycoprotein that did not form higher polymers and was not associated with other polypeptide chains. The Thy-1 glycoprotein could be found in two forms, one binding to lentil lectin, the other not. Both forms had the same detectable antigens and were of a similar but not identical size. After sodium dodecyl sulphate-polyacrylamide-gel electrophoresis the apparent molecular weight of Thy-1 binding to lentil lectin was 25 000, whereas that not binding to the lectin was 27 000, with heterogeneity towards forms of apparently higher molecular weight. Images PLATE 4 PLATE 1 PLATE 2 PLATE 3 PMID:56177

  16. Excellent performances of energy harvester using cantilever driving double-clamped 0.7Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}-0.3PbTiO{sub 3} plates and symmetric middle-stops

    SciTech Connect

    Zeng, Zhou; Xu, Qing; Ren, Bo; Lin, Di; Di, Wenning; Luo, Haosu Wang, Dong

    2015-10-26

    We present a high performance nonlinear piezoelectric energy harvester constituted by a cantilever with symmetrically middle-stops and double-clamped piezoelectric plates based on piezoelectric single crystal 0.7Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}-0.3PbTiO{sub 3}. Electrical properties of the device under different excitation frequencies, accelerations, and load resistances are studied systematically. Under a low acceleration of 3 m/s{sup 2} (0.3 g), a peak voltage of 26.2 V and a maximum normalized power of 25.6 mW/g{sup 2} were obtained across a matching impedance of 600 kΩ with favorable bandwidths. The low excitation acceleration and excellent performances indicate that the device can be a promising candidate for energy harvesting in low-power electronics and wireless sensors.

  17. Isolation and characterization of human plasma alpha 1-proteinase inhibitor and a conformational study of its interaction with proteinases.

    PubMed Central

    Saklatvala, J; Wood, G C; White, D D

    1976-01-01

    1. alpha 1-Proteinase inhibitor was isolated from human plasma by a five-step procedure. Isoelectric focusing showed that six components focused between pH4.85 and 4.95. 2. The mol.wt. of the inhibitor was 52000 by sedimentation equilibrium and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. The amino acid and carbohydrate compositions of the inhibitor were also determined. 3. The far-u.v.c.d. (circular-dichroism) spectrum indicated that the inhibitor had about 36% alpha-helical content. 4. The loss of proteinase-inhibitory activity when the inhibitor was exposed to pH values less than 5.0 or greater than 10.5 was accompanied by small changes in the far-u.v.c.d. spectrum and large changes in the near-u.v.c.d. spectrum. The change at alkaline pH was associated with ionization of tyrosine residues. 5. Interaction of inhibitor with chymotrypsin caused perturbation of the c.d. spectrum and this was used to follow the interaction and show a 1:1 stoicheiometry. 6. C.d., electrophoresis and isoelectric focusing showed that the inhibitor-enzyme complex is degraded by free enzyme. 7. Parallel studies with trypsin indicated that it too forms a 1:1 complex with inhibitor and is degraded by excess of enzyme. Images PLATE 2 PLATE 3 PLATE 4 PLATE 5 PLATE 6 PLATE 1 PMID:9069

  18. Loading-unloading response of circular GLARE fiber-metal laminates under lateral indentation

    NASA Astrophysics Data System (ADS)

    Tsamasphyros, George J.; Bikakis, George S.

    2015-01-01

    GLARE is a Fiber-Metal laminated material used in aerospace structures which are frequently subjected to various impact damages. Hence, the response of GLARE plates subjected to lateral indentation is very important. In this paper, analytical expressions are derived and a non-linear finite element modeling procedure is proposed in order to predict the static load-indentation curves of circular GLARE plates during loading and unloading by a hemispherical indentor. We have recently published analytical formulas and a finite element procedure for the static indentation of circular GLARE plates which are now used during the loading stage. Here, considering that aluminum layers are in a state of membrane yield and employing energy balance during unloading, the unloading path is determined. Using this unloading path, an algebraic equation is derived for calculating the permanent dent depth of the GLARE plate after the indentor's withdrawal. Furthermore, our finite element procedure is modified in order to simulate the unloading stage as well. The derived formulas and the proposed finite element modeling procedure are applied successfully to GLARE 2-2/1-0.3 and to GLARE 3-3/2-0.4 circular plates. The analytical results are compared with corresponding FEM results and a good agreement is found. The analytically calculated permanent dent depth is within 6 % for the GLARE 2 plate, and within 7 % for the GLARE 3 plate, of the corresponding numerically calculated result. No other solution of this problem is known to the authors.

  19. Fractionation of liver plasma membranes prepared by zonal centrifugation

    PubMed Central

    Evans, W. H.

    1970-01-01

    1. Plasma membranes were isolated from crude nuclear sediments from mouse and rat liver by a rate-dependent centrifugation through a sucrose density gradient contained in the `A' type zonal rotor. 2. The membranes were further purified by isopycnic centrifugation, and characterized enzymically, chemically and morphologically. 3. When the plasma-membrane fraction of sucrose density 1.17g/cm3 was dispersed in a tight-fitting homogenizer, two subfractions of densities 1.12 and 1.18 were obtained by isopycnic centrifugation. 4. The light subfraction contained 5′-nucleotidase, nucleoside diphosphatase, leucine naphthylamidase and Mg2+-stimulated adenosine triphosphatase activities at higher specific activities than unfractionated membranes. The heavy subfraction was deficient in the above enzymes but contained higher Na++K+-stimulated adenosine triphosphatase activity. 5. The light subfraction contained twice as much phospholipid and cholesterol, and three times as much N-acetylneuraminic acid relative to unit protein weight as the heavy subfraction. Polyacrylamide-gel electrophoresis indicated differences in protein composition. 6. Electron microscopy showed the light subfraction to be vesicular. The heavy subfraction contained membrane strips with junctional complexes in addition to vesicles. ImagesPLATE 2PLATE 3PLATE 1 PMID:4315049

  20. A simple plaque-inhibition test for the study of arthropod-borne viruses

    PubMed Central

    Porterfield, J. S.

    1960-01-01

    The plaque-neutralization method developed by Dulbecco and co-workers for the study of the virus of western equine encephalomyelitis in cultures of chick fibroblasts, though probably unequalled for accuracy, has not been adopted for general use in laboratories engaged in research on the arthropod-borne viruses, for two reasons: (a) the belief that the technique would be suitable only for viruses with a powerful cytopathic effect on chick-embryo cells, and (b) the laborious procedures involved. The simple plaque-inhibition test described in this paper was devised with the requirements of the field or diagnostic laboratory in mind; while less precise than Dulbecco's method, this test is sufficiently accurate for many purposes and is far less laborious. The range of applicability of the technique is discussed, the author claiming that it can be used both as a qualitative test for the presence of neutralizing antibodies to a particular plaque-producing virus and as a test for the identification of unknown plaque-producing viruses. ImagesPLATE 4PLATE 2PLATE 1PLATE 3 PMID:14434290

  1. Isolation of chick intestinal nuclei. Effect of vitamin D3 on nuclear metabolism

    PubMed Central

    Lawson, D. E. M.; Wilson, P. W.; Barker, D. C.; Kodicek, E.

    1969-01-01

    1. Chick intestinal nuclei were isolated, with practically no contamination from other organelles and whole cells, by centrifugation through 2·4m-sucrose. 2. The proportions of RNA, DNA and protein of the isolated nuclei were unaffected by the vitamin D status of the birds. The RNA/DNA ratio was 0·15. 3. The incorporation of [5-3H]orotic acid into the rapidly labelled intestinal nuclear RNA, after a 10min. pulse of the orotic acid, was increased in vitamin D-deficient chicks only 10min. after a 125μg. dose of cholecalciferol. 4. There was no stimulation of the DNA-dependent RNA polymerase activity of the isolated nuclei from birds treated with cholecalciferol. 5. The results are discussed in relation to the changes occurring during the lag period, after administration of cholecalciferol and before Ca2+ transport is detected, and the function of the vitamin. ImagesPLATE 1PLATE 2PLATE 3 PMID:4314118

  2. Wave-length dependencies of light scattering in normal and cold swollen rabbit corneas and their structural implications*

    PubMed Central

    Farrell, R. A.; McCally, R. L.; Tatham, P. E. R.

    1973-01-01

    1. The studies described herein involve the use of light scattering measurements to characterize the ultrastructural arrangement of the constituent collagen fibrils in rabbit corneal stromas. 2. Theoretical light scattering techniques for calculating the scattering to be expected from the structures revealed by electron micrographs are discussed, and comparison with the experimental light scattering tests the validity of these structures. 3. The wave-length dependence of light transmission and of angular light scattering from normal corneas is in agreement with the short range ordering of collagen fibrils depicted in electron micrographs. 4. The transmission measurements on oedematous rabbit corneas indicate that transmission decreases linearly with the ratio of thickness to normal thickness. 5. The wave-length dependence of transmission through cold swollen corneas indicates that the increased scattering is caused by large inhomogeneities in the ultrastructure. Electron micrographs do, indeed, reveal the presence of such inhomogeneities in the form of large regions completely devoid of fibrils. ImagesPlate 1Plate 2Plate 3 PMID:4754873

  3. U-Pb zircon geochronology and geological evolution of the Halaban- Al Amar region of the eastern Arabian Shield, Kingdom of Saudi Arabia.

    USGS Publications Warehouse

    Stacey, J.S.; Stoeser, D.B.; Greenwood, W.R.; Fischer, L.B.

    1984-01-01

    U/Pb zircon model ages for 11 major units from this region indicate three stages of evolution: 1) plate convergence, 2) plate collision and 3) post-orogenic intracratonic activity. Convergence occurred between the western Afif and eastern Ar Rayn plates that were separated by oceanic crust. Remnants of crust now comprise the ophiolitic complexes of the Urd group; the oldest plutonic unit studied is from one such complex, and gave an age of 694-698 m.y., while detrital zircons from an intercalated sedimentary formation were derived from source rocks with a mean age of 710 m.y. Plate convergence was terminated by collision of the two plates during the Al Amar orogeny which began at -670 m.y.; during collision, the Urd group rocks were deformed and in part obducted on to one or other of the plates. Synorogenic granitic rocks were intruded from 670 to 640 m.y., followed from 640 to 630 m.y. by unfoliated dioritic plutons emplaced in the Ar Rayn block.-R.A.H.

  4. Biotransformation enzymes in the rodent nasal mucosa: the value of a histochemical approach.

    PubMed Central

    Bogdanffy, M S

    1990-01-01

    An increasing number of chemicals have been identified as being toxic to the nasal mucosa of rats. While many chemicals exert their effects only after inhalation exposure, others are toxic following systemic administration, suggesting that factors other than direct deposition on the nasal mucosa may be important in mechanisms of nasal toxicity. The mucosal lining of the nasal cavity consists of a heterogeneous population of ciliated and nonciliated cells, secretory cells, sensory cells, and glandular and other cell types. For chemicals that are metabolized in the nasal mucosa, the balance between metabolic activation and detoxication within a cell type may be a key factor in determining whether that cell type will be a target for toxicity. Recent research in the area of xenobiotic metabolism in nasal mucosa has demonstrated the presence of many enzymes previously described in other tissues. In particular, carboxylesterase, aldehyde dehydrogenase, cytochromes P-450, epoxide hydrolase, and glutathione S-transferases have been localized by histochemical techniques. The distribution of these enzymes appears to be cell-type-specific and the presence of the enzyme may predispose particular cell types to enhanced susceptibility or resistance to chemical-induced injury. This paper reviews the distribution of these enzymes within the nasal mucosa in the context of their contribution to xenobiotic metabolism. The localization of the enzymes by histochemical techniques has provided important information on the potential mechanism of action of esters, aldehydes, and cytochrome P-450 substrates known to injure the nasal mucosa. Images PLATE 1. PLATE 2. PLATE 3. PMID:2200661

  5. The storage of endogenous noradrenaline in sympathetic nerve terminals

    PubMed Central

    Bisby, M. A.; Fillenz, Marianne

    1971-01-01

    1. The subcellular distribution of noradrenaline in sympathetic nerve terminals of rat vas deferens and cat spleen has been studied by cell fractionation methods combined with fluorescence and electronmicroscopic histochemical methods for noradrenaline. 2. Pinched-off axon varicosities (synaptosomes) were isolated and identified by fluorescence and electronmicroscopy in the mitochondrial pellet. 3. The proportion of large to small dense-cored vesicles in electronmicrographs of sympathetic nerve terminals varies in different organs. In rat vas deferens 4% and in cat spleen 20% are large vesicles. 4. Density gradients of rat vas deferens have a single low density peak of noradrenaline at 0·6 M sucrose, whereas those of cat spleen have an additional peak of noradrenaline at 1·1 M sucrose. 5. Small dense-cored vesicles were identified electronmicroscopically in the low density fractions and large dense-cored vesicles in the high density fractions from density gradients. 6. We conclude that both small and large dense-cored vesicles store noradrenaline. ImagesPlate 1Plate 2Plate 3 PMID:5579649

  6. Lithospheric-scale effects of a subduction-driven Alboran plate: improved neotectonic modeling

    NASA Astrophysics Data System (ADS)

    Neres, Marta; Carafa, Michele; Terrinha, Pedro; Fernandes, Rui; Matias, Luis; Duarte, João; Barba, Salvatore

    2016-04-01

    The presence of a subducted slab under the Gibraltar arc is now widely accepted. However, discussion still remains on whether subduction is active and what is its influence in the lithospheric processes, in particular in the observed geodesy, deformation rates and seismicity. Aiming at bringing new insights into the discussion, we have performed a neotectonic numerical study of a segment of the Africa-Eurasia plate boundary, from the Gloria fault to the Northern Algerian margin. Specifically, we have tested the effect of including or excluding an independently driven Alboran plate, i.e. testing active subduction versus inactive subduction (2plates versus 3plates scenarios). We used the dynamic code SHELLS (Bird et al., 2008) to model the surface velocity field and the ongoing deformation, using a new up-to-date simplified tectonic map of the region, new available lithospheric data and boundary conditions determined from two alternative Africa-Eurasia angular velocities, respectively: SEGAL2013, a new pole based on stable Africa and stable Eurasia gps data (last decades); and MORVEL, a geological-scale pole (3.16 Ma). We also extensively studied the variation within the parametric space of fault friction coefficient, subduction resistance and surface velocities imposed to the Alboran plate. The final run comprised a total of 5240 experiments, and each generated model was scored against geodetic velocities, stress direction data and seismic strain rates. The preferred model corresponds to the 3plates scenario, SEGAL2013 pole and fault friction of 0.225, with scoring results: gps misfit of 0.78 mm/yr; SHmax misfit of 13.6° and correlation with seismic strain rate of 0.62, significantly better than previous models. We present predicted fault slip rates for the recognized active structures and off-faults permanent strain rates, which can be used for seismic and tsunami hazard calculations (the initial motivation for this work was contributing for calculation of

  7. Review of Current Experience on Intermediate Heat Exchanger (IHX) and A Recommended Code Approach

    SciTech Connect

    Duane Spencer; Kevin McCoy

    2010-02-02

    The purpose of the ASME/DOE Gen IV Task 7 Part I is to review the current experience on various high temperature reactor intermediate heat exchanger (IHX) concepts. There are several different IHX concepts that could be envisioned for HTR/VHTR applications in a range of temperature from 850C to 950C. The concepts that will be primarily discussed herein are: (1) Tubular Helical Coil Heat Exchanger (THCHE); (2) Plate-Stamped Heat Exchanger (PSHE); (3) Plate-Fin Heat Exchanger (PFHE); and (4) Plate-Machined Heat Exchanger (PMHE). The primary coolant of the NGNP is potentially subject to radioactive contamination by the core as well as contamination from the secondary loop fluid. To isolate the radioactivity to minimize radiation doses to personnel, and protect the primary circuit from contamination, intermediate heat exchangers (IHXs) have been proposed as a means for separating the primary circuit of the NGNP (Next Generation Nuclear Plant) or other process heat application from the remainder of the plant. This task will first review the different concepts of IHX that could be envisioned for HTR/VHTR applications in a range of temperature from 850 to 950 C. This will cover shell-and-tube and compact designs (including the platefin concept). The review will then discuss the maturity of the concepts in terms of design, fabricability and component testing (or feedback from experience when applicable). Particular attention will be paid to the feasibility of developing the IHX concepts for the NGNP with operation expected in 2018-2021. This report will also discuss material candidates for IHX applications and will discuss specific issues that will have to be addressed in the context of the HTR design (thermal aging, corrosion, creep, creep-fatigue, etc). Particular attention will be paid to specific issues associated with operation at the upper end of the creep regime.

  8. Destruction of a single cell in the central nervous system of the leech as a means of analysing its connexions and functional role

    PubMed Central

    Bowling, D.; Nicholls, J.; Parnas, I.

    1978-01-01

    A method has been devised for killing an individual neurone in the C.N.S. of the leech by injecting it with Pronase. The technique has been used to examine the role of individual sensory and motor cells involved in producing reflex movements. 1. After a neurone was injected with Pronase, either in an intact animal or an isolated ganglion, its cell body lost its resting and action potentials. Some hours later the injected cell's axons in the periphery failed to conduct impulses. In the intact animal the cell body could no longer be discerned after a few weeks. 2. To test for destruction of processes within the neuropile, cells were injected first with the enzyme horseradish peroxidase (HRP) and then several hours later with Pronase. Absence of the characteristic HRP reaction product indicated that Pronase had spread throughout the arborization of the cell. 3. Injection of Pronase into one cell did not produce overt electrophysiological or anatomical changes in other cells in the ganglion including neurones that were originally electrically coupled to the killed cell. 4. Evidence that an individual cell was the only motoneurone supplying particular muscles was provided by destruction of that cell in otherwise intact animals, which resulted in a characteristic motor deficit in the area supplied by the killed cell. Over a period of months, functional recovery of the affected muscles occurred by way of homologous cells in adjacent ganglia. 5. A further application of the technique was to trace the connexion that a particular sensory neurone makes onto two motoneurones that are electrically coupled. Normally, the sensory neurone gives rise to excitatory potentials in both post-synaptic cells. Synaptic potentials could still be recorded in one motor cell after the other had been destroyed by Pronase, indicating that synapses were made directly onto both of the motoneurones. ImagesText-fig. 4Plate 2Plate 3Plate 4Plate 1 PMID:722515

  9. Do Faults Strengthen or Weaken between Earthquakes?

    NASA Astrophysics Data System (ADS)

    Turcotte, D. L.; Rundle, J. B.; Shcherbakov, R.; Abaimov, S. G.

    2006-12-01

    An important question is whether faults strengthen (heal) or weaken (become damaged) between earthquakes. We argue that if faults heal earthquakes will be concentrated on the strongest faults. Since this is not observed we argue that faults weaken. In order to quantify this discussion we consider a "parallel" slider-block model. Many slider-block models have been considered as analogs for the stick-slip behavior of faults. A classic problem was a pair of slider-blocks in series connected to each other by a connector spring and to a loader plate by two loader springs. The constant velocity loader plate pulls the slider blocks over a surface. This problem was shown to exhibit classic chaotic behavior as long as the symmetry was broken. In this paper we consider the analogous parallel problem. We consider 6 plates. Plate 6 moves at a constant velocity V relative to the fixed plate 1. Plate 1 is connected to plate 2 by a leaf spring and plate 2 slides along plate 3. Plate 3 is connected to plate 4 by a leaf spring and plate 4 slides over plate 5. Finally plate 5 is connected to plate 6 by a leaf spring. With velocity weakening friction, stick-slip behavior will be observed between plates 2 and 3 or between 4 and 5. If the static coefficient of friction between plates 2 and 3 is smaller, slip is restricted to the slip plane between plates 2 and 3. No slip will occur on the slip plane between plates 4 and 5. In order for slip to occur on both slip planes the static coefficient of friction must decrease with time, the friction must have memory. We show that this behavior is obtained with a damage based coefficient of friction. The applicability of rate and state friction laws will also be discussed.

  10. Lead and wine. Eberhard Gockel and the colica Pictonum

    PubMed Central

    Eisinger, Josef

    1982-01-01

    The colica Pictonum or colic of Poitou, under these and many other names, was a frequent, widespread, and deadly disease from Roman times until the eighteenth century. Its unique pathognomonic, notably a severe colic succeeded by paralysis and other central nervous system dysfunction, makes it possible to identify the disease with certainty as chronic lead disease, usually caused by the ingestion of lead-adulterated wines. The custom of sweetening and preserving sour wines with lead-containing additives is traced to the Romans. They had made the empirical discovery that sapa, a syrup prepared by concentrating must in a lead vessel, kept wine from spoiling and that it had, moreover, an agreeable flavour. Reports of outbreaks of the colica Pictonum appear in the medical literature from Roman times, but the correct aetiology of the disease was not discovered until the seventeenth century following a series of outbreaks in Southern Germany which were related to unfavourable climatic and political conditions. The connexion between the disease and prevailing methods for “correcting” wines was drawn in 1696 by Eberhard Gockel, then the city physician of Ulm. This achievement can be traced to his familiarity with Samuel Stockhausen's work on plumbism among miners and potters, as well as to the favourable epidemiological situation presented by Gockel's monastic patients. From the literary evidence assembled here and from experimental determinations of the lead content of sapa and similar concentrates, it is possible to estimate the lead levels and toxicity of wines from various eras. The levels range up to 80 mg/l and make it apparent that many wines were sufficiently toxic to account for the incidence and severity of the colica Pictonum. Explanations for the disastrous persistence of the colic of Poitou are discussed, as are the similarities between Gockel's approach and the methods of modern environmental medicine. ImagesPlate 4.Plate 1.Plate 2.Plate 3. PMID:6750289

  11. Specific protein synthesis in isolated rat testis leydig cells. Influence of luteinizing hormone and cycloheximide.

    PubMed Central

    Janszen, F H; Cooke, B A; van der Molen, H J

    1977-01-01

    The effect of luteinizing hormone (luteotropin) and cycloheximide on specific protein synthesis in rat testis Leydig cells has been investigated. Proteins were labelled with either I114C]leucine, [3H]leucine or [35S]methionine during incubation with Leydig-cell suspensions in vitro. Total protein was extracted from the cells and separated by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. No detectable increase in the synthesis of specific proteins could be observed after incubation of Leydig cells with luteinizing hormone for up to 1 h. However, after a 2h incubation period, an increase in [35S]methionine incorporation was observed in a protein with an apparent mol.wt. of 21000 (referred to as 'protein 21"). When, after labelling of this protein with [35S]-methionine, Leydig cells were incubated for another 30min with cycloheximide, no decrease in radioactivity of this protein band was observed, indicating that it does not have a short half-life. However, another protein band was detected, which after incubation with cycloheximide disappeared rapidly, the reaction following first-order kinetics, with a half-life of about 11 min. This protein, with an apparent mol.wt. of 33000 (referred to as "protein 33"), was found to be located in the particulate fraction of the Leydig cell, and could not be demonstrated in other rat testis-cell types or blood cells. No effect of luteinizing hormone on molecular weight, subcellular localization or half-life of protein 33 was observed. A possible role for protein 33 and protein 21 in the mechanism of action of luteinizing hormone on testosterone production of Leydig cells is discussed. Images PLATE 4 PLATE 1 PLATE 2 PLATE 3 PMID:849289

  12. Fukuyoa paulensis gen. et sp. nov., a New Genus for the Globular Species of the Dinoflagellate Gambierdiscus (Dinophyceae)

    PubMed Central

    Gómez, Fernando; Qiu, Dajun; Lopes, Rubens M.; Lin, Senjie

    2015-01-01

    The marine epiphytic dinoflagellate Gambierdiscus is a toxicologically important genus responsible for ciguatera fish poisoning, the principal cause of non-bacterial illness associated with fish consumption. The genus currently contains species exhibiting either globular or anterior-posteriorly compressed morphologies with marked differences in cell shape and plate arrangement. Here we report a third globular, epiphytic and tychoplanktonic species from the coasts of Ubatuba, Brazil. The new species can be distinguished from G. yasumotoi and G. ruetzleri by its broader first apical plate that occupies a larger portion of the epitheca. Accordingly, phylogenetic trees from small subunit (SSU) and large subunit (LSU) ribosomal DNA sequences also showed strongly supported separation of the new species from the G. yasumotoi / G. ruetzleri group albeit with short distance. The molecular phylogenies, which included new sequences of the planktonic species Goniodoma polyedricum, further indicated that the globular species of Gambierdiscus formed a tight clade, clearly separated (with strong bootstrap support) from the clade of lenticular species including the type for Gambierdiscus. The morphological and molecular data in concert support the split of Gambierdiscus sensu lato into two genera. Gambierdiscus sensu stricto should be reserved for the species with lenticular shapes, highly compressed anterioposteriorly, with short-shank fishhook apical pore plate, large 2' plate, low and ascending cingular displacement, and pouch-like sulcal morphology. The new genus name Fukuyoa gen. nov. should be applied to the globular species, slightly laterally compressed, with long-shank fishhook apical pore plate, large 1' plate, greater and descending cingular displacement, and not pouch-like vertically-oriented sulcal morphology. Fukuyoa contains the new species Fukuyoa paulensis gen. et sp. nov., and F. yasumotoi comb. nov. and F. ruetzleri comb. nov. PMID:25831082

  13. Membrane properties and selective connexions of identified leech neurones in culture

    PubMed Central

    Fuchs, Paul A.; Nicholls, John G.; Ready, Donald F.

    1981-01-01

    mediated inhibitory potentials became apparent. 8. Isolated, identified leech neurones not only survive but regenerate processes and are capable of forming selective connexions in culture. The ability to define interactions between isolated pairs of cells offers the opportunity to explore in detail problems relating to synapse formation and cell—cell recognition. ImagesFig. 7Fig. 11Fig. 12Fig. 13Plate 1Plate 3Plate 4Plate 2 PMID:7320865

  14. Quantitative investigations of the adhesiveness of circulating polymorphonuclear leucocytes to blood vessel walls

    PubMed Central

    Atherton, Anne; Born, G. V. R.

    1972-01-01

    culture filtrate which are chemotactic to granulocytes in vitro. These agents did not cause alterations in mean blood flow velocity in the observed venules which might have accounted for the effect on the rolling granulocyte counts. When E. coli culture filtrate was perfused through mouse intestine the increase in rolling granulocyte count in the draining venous blood was proportional to the logarithm of the concentration of filtrate. 7. The rolling granulocyte count was also increased by the local application of plasma globulin permeability factor or lymph node permeability factor. 8. Granulocyte counts in standard histological sections showed no significant increases in control preparations but considerable increases following the application of Hammarsten casein. ImagesPlate 3Plate 4Plate 1Plate 2 PMID:4624453

  15. Single-level cervical radiculopathy: clinical outcome and cost-effectiveness of four techniques of anterior cervical discectomy and fusion and disc arthroplasty.

    PubMed

    Bhadra, Arup K; Raman, A S; Casey, Adrian T H; Crawford, R J

    2009-02-01

    Although there are several accepted methods of surgical treatment for single-level cervical radiculopathy, the choice depend on the surgeon's preference. The techniques may vary in peri-operative morbidity, short- and long-term outcome, but no study so far has analyzed their cost-effectiveness. This study might give some insight in balancing cost and effectiveness and deciding the right technique. Sixty consecutive patients (15 each group), mean age 36 (range 24-76 years) with single-level cervical disc disease underwent surgical treatment with four different techniques in two centers over the period of 1999-2005. The four groups were--(1) plate and tricortical autograft, (2) plate, cage, and bone substitute, (3) cage only, and (4) disc arthroplasty. The data was collected prospectively according to our protocol and subsequently analyzed. The clinical outcome was assessed comparing visual analog scale (VAS) of neck pain and, short form 12 (SF12) questionnaire both pre- and postoperatively. The radiological assessment was done for fusion rate and postoperative related possible complications at 3 months, 6 months, 1 year, and final follow-up. The cost analysis was done calculating the operative time, hospital stay, implant cost together. The mean follow-up period was 31 months (range 28-43 months). The clinical outcome in terms of VAS of neck and arm pain and SF12 physical and mental score improvement (P=0.001) were comparable with all four techniques. The radiological fusion rate was comparable to current available data. As the hospital stay was longer (average 5 days) with plate and autograft group, the total cost was maximum (average 2,920 pound sterling) with this group. There was satisfactory clinical and radiological outcome with all four techniques. Using the cage alone was the most cost-effective technique, but the disc arthroplasty was comparable to the use of cage and plate. Anterior cervical discectomy and fusion is an established surgical treatment for

  16. The function of the sodium pump during differentiation of amphibian embryonic neurones.

    PubMed Central

    Messenger, E A; Warner, A E

    1979-01-01

    nervous systems. 10(-6) M-strophanthidin had little effect on the volume of grey matter, but reduced the white matter by 50%. 12. The results are consistent with the view that strophanthidin achieves its effect on neural differentiation by inhibiting the sodium pump. They are discussed in the light of the suggestion that activation of the sodium pump is an essential part of nerual differentiation. Images Plate 1 Plate 2 Plate 3 PMID:490420

  17. The maximum speed of shortening in living and skinned frog muscle fibres.

    PubMed Central

    Julian, F J; Rome, L C; Stephenson, D G; Striz, S

    1986-01-01

    .5 degrees C. In five fibres, the linear extrapolation of low loads (0.01-0.05 P0) showed that the Hill equation underestimated the true Viso by 6%. The slack test with mechanically skinned fibres was calibrated by taking a series of photographic exposures of the fibre at various times following each length step. Vu = 6.12 muscle lengths/s +/- 0.44 (mean +/- S.E., n = 10) and the intercept was 0.0585 L0 +/- 0.0069 (mean +/- S.E., n = 10).(ABSTRACT TRUNCATED AT 400 WORDS) Images Plate 1 Plate 2 Plate 3 PMID:3485715

  18. Plate Tectonic Cycle. K-6 Science Curriculum.

    ERIC Educational Resources Information Center

    Blueford, J. R.; And Others

    Plate Tectonics Cycle is one of the units of a K-6 unified science curriculum program. The unit consists of four organizing sub-themes: (1) volcanoes (covering formation, distribution, and major volcanic groups); (2) earthquakes (with investigations on wave movements, seismograms and sub-suface earth currents); (3) plate tectonics (providing maps…

  19. 12. Historic American Buildings Survey Photocopy, Yale University ENGRAVING, EAST ...

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

    12. Historic American Buildings Survey Photocopy, Yale University ENGRAVING, EAST FACADE: FLOOR PLAN (The New Englander, Vol. I, No. III, July 1843) AP2.N5, betw p. 304-307, 2 plates engr. By Daggett, Hinman + Co D.C. Hinman, del. Source: Yale Memorabilia, Yale University Sterling Memorial Library - Yale University, Dwight Hall, 69 High Street, New Haven, New Haven County, CT

  20. Some first experiments on the photometric calibration of Schmidt plates against the Tycho catalogue

    NASA Technical Reports Server (NTRS)

    Morrison, J. E.; Lasker, B.; McLean, B.; Bucciarelli, B.; Spagna, A.; Zacchei, A.

    1997-01-01

    Preliminary work carried out with the aim of reducing the Guide Star Catalog (GSC2) measurements of the Palomar 2 plates with the Tycho catalog for a 625 sq deg test field centered on the North Galactic Pole, is reported on and the results are presented. The emphasis was on the photometric calibrations.

  1. Unique organic remains from an upper Permian coal bearing sequence in the Talcher Coalfield, Orissa, India

    SciTech Connect

    Tripathi, A.

    2004-07-01

    The playnological assemblage of coal bearing upper Permian sequence of Talcher Coalfield registers presence of some peculiar organic remains. These are described as Orissiella gen. nov., which is characterized by a vesicle with collar-like structure at the oral end, spines and or corrugations on the body. The affinity and palaeoecological significance of Orissiella is also discussed. 12 refs., 4 figs., 2 plates.

  2. Electron microscopy studies of lutetium doped erbium silicide (Er{sub 0.9}Lu{sub 0.1}){sub 5}Si{sub 4}

    SciTech Connect

    Cao, Q. Chumbley, L.S.

    2011-08-15

    Examination of bulk microstructures of lutetium doped erbium silicide (Er{sub 0.9}Lu{sub 0.1}){sub 5}Si{sub 4} (space group: Pnma) using scanning and transmission electron microscopy (SEM, TEM) reveals the existence of thin plates of a hexagonal phase (space group: P6{sub 3}/mcm) where the stoichiometric ratio in moles between the rare earths and Si is 5 to 3, i. e the 5:3 phase. The orientation relationship between the matrix and the plates was determined as [010]{sub m} {approx} -parallel [-1010]{sub p.} This observation adds credence to the assumption that all linear features noted in alloys of the rare-earth intermetallic family R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} are of the stoichiometric ratio 5:3 and possess a common orientation relationship with the parent 5:4 alloys. - Highlights: {yields} The linear features observed in the (Er{sub 0.9}Lu{sub 0.1}){sub 5}Si{sub 4} sample are hexagonal 5:3 plates. {yields} Thickness of 5:3 plates in 5:4 alloys made by tri-arc pulling is greater than made by arc-melting. {yields} The orientation relationship between 5:3 plates and the matrix is [010]{sub m} {approx} ||[-1010]{sub p}.

  3. Proximal humeral fractures: a biomechanical comparison of locking plate constructs in a cadaveric 3-part fracture model.

    PubMed

    Rose, David M; Sutter, Edward G; Mears, Simon C; Gupta, Rohit R; Belkoff, Stephen M

    2010-11-01

    The purpose of our study was to biomechanically compare, under cyclic loading conditions, fracture site motion, humeral head collapse, and intra-articular hardware penetration in simulated 3-part osteoporotic proximal humeral fractures stabilized with 1 of 2 locking-plate constructs. We performed fixation on simulated 3-part proximal humeral fractures in 10 pairs of cadaveric osteoporotic humeri with a Hand Innovations S3 Proximal Humerus Plate (S3 plate) or an LCP Proximal Humerus Plate (LCP plate; 1 each for each pair). The specimens were potted, mounted on a materials testing machine, and subjected to 5000 cycles of abduction in the scapular plane, loading through the supraspinatus tendon. Interfragmentary displacement at 2 virtual points (the most medial aspect of the calcar and the most superior aspect of the osteotomy line between the greater tuberosity and humeral head) was measured using an optical tracking system. Humeral head rotation was also measured. We used a generalized linear latent and mixed model to check for an effect of cyclic loading and treatment on the parameters of interest (significance, P < .05). After cyclic loading, the S3 plate humeri showed significantly greater displacement of the greater tuberosity fragment and rotation of the humeral head and a trend (not a significant difference) toward greater displacement at the calcar. No hardware penetration was noted for either repair. Although the S3 plate repairs resulted in significantly more fracture site motion, it is unknown whether the magnitude of the motion is clinically significant. PMID:23569665

  4. Linewidth narrowing of a tunable mode-locked pumped continuous-wave Ce:LiCAF laser.

    PubMed

    Wellmann, Barbara; Kitzler, Ondrej; Spence, David J; Coutts, David W

    2015-07-01

    We report birefringent tuning using single and multiple magnesium fluoride (MgF(2)) Brewster tuning plates in a mode-locked pumped continuous-wave Ce:LiCAF laser. Depending on the thickness of the MgF(2) plates used, continuous tuning over a range of up to 13 nm from 284.5 to 297.5 nm with a full width at half-maximum linewidth of 14 pm (50 GHz) was achieved. By combining MgF(2) plates with etalons, the linewidth of the laser was narrowed down to 0.75 pm (2.7 GHz). This generated narrowband output is suitable for many applications in spectroscopy, cold-atom manipulation, and sensing. PMID:26125368

  5. Solid state precursor strategy for synthesizing hollow TiO2 boxes with a high percentage of reactive {001} facets exposed.

    PubMed

    Xie, Shuifen; Han, Xiguang; Kuang, Qin; Fu, Jie; Zhang, Lei; Xie, Zhaoxiong; Zheng, Lansun

    2011-06-21

    Three-dimensional, hollow, anatase TiO(2) boxes, each was enclosed by six single-crystalline TiO(2) plates exposed with highly reactive {001} facets, were facilely obtained by calcining a cubic TiOF(2) solid precursor at 500-600 °C. The formation of such particular nanostructures is attributed to the hard self-template restriction and the adsorption of F(-) ions from the TiOF(2). PMID:21559545

  6. Production of monoclonal antibodies to hepatitis B surface and core antigens, and use in the detection of viral antigens in liver biopsies.

    PubMed Central

    Tedder, R. S.; Guarascio, P.; Yao, J. L.; Lord, R. B.; Eddleston, A. L.

    1983-01-01

    Hybridomas secreting monoclonal antibodies to HBsAg and HBcAg were prepared from immunized mice. An antibody capture radioimmunoassay was used to detect and select appropriate hybrids for propagation and cloning. The advantages of this assay were discussed. The resulting monoclonal antibodies were compared with conventional polyclonal antisera for the detection of virus antigens in liver tissue and found to give excellent results. Images Plate 2 Plate 1 PMID:6337208

  7. 78 FR 40776 - Issuance of Regulatory Guide 1.124 and Regulatory Guide 1.130

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-08

    ...The U.S. Nuclear Regulatory Commission (NRC) is issuing Revision 3 of Regulatory Guide (RG) 1.124, ``Service Limits and Loading Combinations for Class 1 Linear-Type Supports,'' and Revision 3 of RG 1.130, ``Service Limits and Loading Combinations for Class 1 Plate-and- Shell-Type Supports.'' There are no substantive changes to these regulatory guides. The revisions include an update of the......

  8. The proteins in the Z line of insect flight muscle.

    PubMed Central

    Bullard, B; Sainsbury, G M

    1977-01-01

    Z discs were isolated from Lethocerus flight muscle by removing the contractile proteins from myofibrils with a solution of high ionic strength. The protein composition of the Z discs was analysed by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis; the major proteins were alpha-actinin, actin and tropomyosin. Z lines were selectively removed from intact myofibrils by digestion with crude lipase and chymotrypsin, but not by purified lipase. Images PLATE 1 PLATE 2 PMID:849268

  9. Thermal self-oscillations in radiative heat exchange

    SciTech Connect

    Dyakov, S. A.; Dai, J.; Yan, M.; Qiu, M.

    2015-02-09

    We report the effect of relaxation-type self-induced temperature oscillations in the system of two parallel plates of SiO{sub 2} and VO{sub 2} which exchange heat by thermal radiation in vacuum. The non-linear feedback in the self-oscillating system is provided by metal-insulator transition in VO{sub 2}. Using the method of fluctuational electrodynamics, we show that under the action of an external laser of a constant power, the temperature of VO{sub 2} plate oscillates around its phase transition value. The period and amplitude of oscillations depend on the geometry of the structure. We found that at 500 nm vacuum gap separating bulk SiO{sub 2} plate and 50 nm thick VO{sub 2} plate, the period of self-oscillations is 2 s and the amplitude is 4 K, which is determined by phase switching at threshold temperatures of phase transition.

  10. Influence of substrate type on structure of C-Pd thin films

    NASA Astrophysics Data System (ADS)

    Kowalska, Ewa; Czerwosz, ElŻbieta; Kozłowski, Miroslaw; Firek, Piotr

    2015-09-01

    C-Pd films were obtained by a two steps' PVD/CVD method (Physical Vapor Deposition/Chemical Vapor Deposition). Investigations of Pd nanograins structure and carbon matrix structure were performed. Many types of substrates (Si, Si covered with DLC layer, Al2O3 plate and AAO membrane) with various developing specific surface area (SSA) were applied and the influence on this surface on obtained films C-Pd was studied. We present the results of Scanning Electron Microscopy (SEM) studies with SE (Secondary Electrons) and LABE (Low Angle Backscattered Electrons) modes. Depending on the substrate type it was possible to obtain many different films and structures with various structural features.

  11. Partial analysis of LDEF experiment A-0114

    NASA Technical Reports Server (NTRS)

    Gregory, John C.

    1991-01-01

    During the contract period, work concentrated on four main components. Data from the UAH silver pin hole camera was analyzed for determination of the mean Long Duration Exposure Facility (LDEF) satellite attitude and stability in orbit, to include pitch and yaw. Chemical testing performed on the AO-114 hot plate determined the form and locus of absorption of cosmogenic beryllium-7. Reaction rates of atomic oxygen with Kapton and other polymeric solids integrated over the whole LDEF orbital lifetime were analyzed. These rates were compared with the JSC estimated values for Space Station exposures. Metal and polymer films exposed on A0114 (C-9 and C-3 plates) were also analyzed.

  12. Environmental and biological monitoring in a lead acid battery manufacturing unit in India.

    PubMed

    Ravichandran, B; Ravibabu, K; Raghavan, S; Krishnamurthy, V; Rajan, B K; Rajmohan, H R

    2005-07-01

    An environmental and biological monitoring of a lead acid battery manufacturing unit was carried out to measure the respirable particulate matter, lead content in working atmosphere and blood lead levels of workers employed in different sections. The results showed high mean air lead concentration in buffing (1444.45 microg/m(3)), plate cutting (430.14 microg/m(3)) and pasting (277.48 microg/m(3)) sections. The mean blood lead levels of employees in these sections were also higher than the values prescribed by ACGIH. PMID:16096364

  13. Characterization of three LYSO crystal batches

    NASA Astrophysics Data System (ADS)

    Yang, Fan; Mao, Rihua; Zhang, Liyuan; Zhu, Ren-Yuan

    2015-06-01

    We report on three LYSO crystal batches characterized at the Caltech crystal laboratory for future HEP experiments: 25 20 cm long crystals for the SuperB experiment; 12 13 cm long crystals for the Mu2e experiment and 623 14×14×1.5 mm3 plates with five holes for a LYSO/W Shashlik matrix for a beam test at Fermilab. Optical and scintillation properties measured are longitudinal transmittance, light output and FWHM energy resolution. Correlations between these properties are also investigated.

  14. Electrical activity of ferroelectric biomaterials and its effects on the adhesion, growth and enzymatic activity of human osteoblast-like cells

    NASA Astrophysics Data System (ADS)

    Vaněk, P.; Kolská, Z.; Luxbacher, T.; García, J. A. L.; Lehocký, M.; Vandrovcová, M.; Bačáková, L.; Petzelt, J.

    2016-05-01

    Ferroelectrics have been, among others, studied as electroactive implant materials. Previous investigations have indicated that such implants induce improved bone formation. If a ferroelectric is immersed in a liquid, an electric double layer and a diffusion layer are formed at the interface. This is decisive for protein adsorption and bioactive behaviour, particularly for the adhesion and growth of cells. The charge distribution can be characterized, in a simplified way, by the zeta potential. We measured the zeta potential in dependence on the surface polarity on poled ferroelectric single crystalline LiNbO3 plates. Both our results and recent results of colloidal probe microscopy indicate that the charge distribution at the surface can be influenced by the surface polarity of ferroelectrics under certain ‘ideal’ conditions (low ionic strength, non-contaminated surface, very low roughness). However, suggested ferroelectric coatings on the surface of implants are far from ideal: they are rough, polycrystalline, and the body fluid is complex and has high ionic strength. In real cases, it can therefore be expected that there is rather low influence of the sign of the surface polarity on the electric diffusion layer and thus on the specific adsorption of proteins. This is supported by our results from studies of the adhesion, growth and the activity of alkaline phosphatase of human osteoblast-like Saos-2 cells on ferroelectric LiNbO3 plates in vitro.

  15. Understanding the differences between the wear of metal-on-metal and ceramic-on-metal total hip replacements.

    PubMed

    Figueiredo-Pina, C G; Yan, Y; Neville, A; Fisher, J

    2008-04-01

    Hip simulator studies have been carried out extensively to understand and test artificial hip implants in vitro as an efficient alternative to obtaining long-term results in vivo. Recent studies have shown that a ceramic-on-metal material combination lowers the wear by up to 100 times in comparison with a typical metal-on-metal design. The reason for this reduction remains unclear and for this reason this study has undertaken simple tribometer tests to understand the fundamental material loss mechanisms in two material combinations: metal-on-metal and ceramic-on-ceramic. A simple-configuration reciprocating pin-on-plate wear study was performed under open-circuit potential (OCP) and with applied cathodic protection (CP) in a serum solution using two tribological couples: firstly, cobalt-chromium (Co-Cr) pins against Co-Cr plates; secondly, Co-Cr pins against alumina (Al2O3) plates. The pin and plate surfaces prior to and after testing were examined by profilometry and scanning electron microscopy. The results showed a marked reduction in wear when CP was applied, indicating that total material degradation under the OCP condition was attributed to corrosion processes. The substitution of the Co-Cr pin with an Al2O3 plate also resulted in a dramatic reduction in wear, probably due to the reduction in the corrosion-wear interactions between the tribological pair. PMID:18491698

  16. Near field thermal memory based on radiative phase bistability of VO2

    NASA Astrophysics Data System (ADS)

    Dyakov, S. A.; Dai, J.; Yan, M.; Qiu, M.

    2015-08-01

    We report the concept of a near-field memory device based on the radiative bistability effect in the system of two closely separated parallel plates of SiO2 and VO2 which exchange heat by thermal radiation in vacuum. We demonstrate that the VO2 plate, having metal-insulator transition at 340 K, has two thermodynamical steady-states. One can switch between the states using an external laser impulse. We show that due to near-field photon tunneling between the plates, the switching time is found to be only 5 ms which is several orders lower than in case of far field.

  17. In vitro mineralization of surface-modified porous polycaprolactone scaffolds in simulated body fluid

    NASA Astrophysics Data System (ADS)

    Ning, Chengyun; Cheng, Haimei; Zhu, Wenjun; Yin, Zhaoyi; Chen, Hao; Zheng, Huade; Lei, Shumei; Yin, Shiheng; Tan, Guoxin

    2008-11-01

    Porous polycaprolactone (PCL) scaffolds were fabricated by combination of porogen-leaching and freeze-drying processes. Ice particulates were used as porogen materials. The porous PCL scaffolds were modified by potassium hydroxide solution with concentration of 1 mol/L at room temperature for 8 h, subsequently biomineralized in simulated body fluid for 2 h and 8 h, respectively. The microstructure and characteristics of the PCL scaffolds were investigated by scanning electron microscope (SEM) and EDS. The results showed (1) PCL scaffolds had high degree of connectivity and different pore sizes. (2) Plate-like apatite was observed on the surface of the scaffolds after being immersed into SBF for 8 h.

  18. Measurement of Casimir force with magnetic materials Alexandr Banishev, Chia-Cheng Chang, Umar Mohideen Department of Physics and Astronomy, University of California, Riverside, USA

    NASA Astrophysics Data System (ADS)

    Banishev, Alexandr; Chang, Chia-Cheng; Mohideen, Umar

    2012-02-01

    The Casimir effect is important in various fields from atomic physics to nanotechnology. According to the Lifshitz theory of the Casimir force, the interaction between two objects depends both on their dielectric permittivity and magenetic permeability. Thus the role of magnetic properties on the Casimir force is interesting particularly due to the possibility of a reduction the Casimir force. In this report we will present the results of a Casimir force measurement between a magnetic material such as nickel coated on SiO2 plate and a Au-coated sphere.

  19. Luminescence spectra of chromium-doped LiGaO 2 crystals as indicator of their phase heterogeneity

    NASA Astrophysics Data System (ADS)

    Meylman, Mikhail L.

    2006-02-01

    The luminescent properties of chromium-doped LiGaO2 single crystals grown from melt by Cz pulling technique are considered and compared with similar data for the other stable crystalline compounds in Li2O-Ga2O3 oxide system. It is proposed that co-crystallization of large LiGaO2 single crystal and a great number of LiGa5O8 spinel microcrystallites of nano scale dimensions is the key cause for appearance of numerous inclusions observed in LiGaO2 plates used as substrates at the III nitride films epitaxial growth.

  20. Technique for the cultural examination of urine using a single plate (the Macba plate).

    PubMed Central

    Naylor, G. R.

    1980-01-01

    This technique for the cultural examination of urine provides, within 24 hours, using a single Petri dish, the colonial appearance of any bacteria present on MacConkey agar and on blood agar, a rough colony count of the bacteria present, their sensitivity to four chemotherapeutic agents, isolated colonies from which further sensitivity tests can be done if necessary and the opportunity to scrutinize contaminating organisms that, even though present in only small numbers, may be of help in diagnostic problems. Images Plate 2 Plate 1 PMID:6762392

  1. Characterization of four prestressed concrete reactor vessel liner steels

    SciTech Connect

    Nanstad, R. K.

    1980-12-01

    A program of fracture toughness testing and analysis is being performed with PCRV steels for HTGRs. This report focuses on background information for the base materials and results of characterization testing, such as tensile and impact properties, chemical composition, and microstructural examination. The steels tested were an SA-508 class 1 forging, two plates of SA-537 class 1, and one plate of SA-537 class 2. Tensile requirements in effect at the time of procurement are met by all four steels. However, the SA-537 class 2 plate would not meet the minimum requirement for yield strength. Drop-weight and Charpy impact tests verified that the RT/sub NDT/ is equal to the NDT for each steel. Charpy impact energies at the NDT range from 40 J (30 ft-lb) for one heat of SA-537 class 1 to 100 J (74 ft-lb) for the SA-537 class 2 plate; upper-shelf energies range from 170 to 310 J (125 to 228 ft-lb) for the same two steels, respectively. The onset of upper-shelf energy occurred at temperatures ranging from 0 to 50/sup 0/C.

  2. The inhibition of bovine and rat parotid deoxyribonuclease I by skeletal muscle actin. A biochemical and immunocytochemical study.

    PubMed Central

    Mannherz, H G; Kreuder, V; Koch, J; Dieckhoff, J; Drenckhahn, D

    1982-01-01

    Rat and bovine parotid gland and pancreas contain deoxyribonuclease I (DNAase I) activities in different amounts. The DNAase I activity in tissue homogenates of bovine and rat parotid gland can be inhibited by addition of monomeric actin, as with the enzyme of bovine pancreas. The isolated DNAase I species from bovine and rat parotid gland differ in their molecular weights and also in their affinities for monomeric actin, being lowest for rat parotid DNAase I (5 X 10(6)M(-1). Antibodies raised against rat and bovine parotid and bovine pancreatic DNAase I can be used to study the subcellular localization of DNAase I in these tissues by indirect immunofluorescence. DNAase I was found to be confined solely to the secretory granules of the tissue from which it was isolated. Images Fig. 3. PLATE 1 Fig. 7. PMID:6297457

  3. Experimental investigation on laser milling of aluminium oxide using a 30 W Q-switched Yb:YAG fiber laser

    NASA Astrophysics Data System (ADS)

    Leone, C.; Genna, S.; Tagliaferri, F.; Palumbo, B.; Dix, M.

    2016-01-01

    In the present study, laser milling tests were carried out on aluminium oxide (Al2O3) plate, 3 mm in thickness, using a Q-Switched 30 W Yb:YAG fiber laser. A systematic approach based on Design of Experiment (DoE) has been successfully adopted with the aim to detect which and how the process parameters affect the laser beam-material interaction, and to explain the effect of the process parameters on the material removal rate and surface quality. The examined process parameters were the laser beam scan speed, the pulse frequency, the total energy released for surface unit, the distance between two consecutive scan lines and the scanning strategy. A full factorial design and ANalysis Of VAriance (ANOVA) were applied for the results analysis. Finally, the various effects of the process parameters on the material removal rate and surface roughness have been analysed and discussed.

  4. Microplasticity and fracture in a Ti-15V-3Cr-3Al-3Sn alloy

    SciTech Connect

    Rabeeh, B.M.; Rokhlin, S.I.; Soboyejo, W.O.

    1996-12-15

    Linear Elasticity is generally considered to occur in most standard textbooks by the strengthening of chemical bonds in the regime below the proportional limit in most materials. In some cases, however, a number of researchers have recognized the possible role of localized microplasticity (microplasticity in this paper refers to localized plasticity on a microstructural level at stresses below the so-called bulk yield stress) in the so-called elastic deformation regime. There is, therefore, a need for careful studies of the micromechanisms of microplasticity in the so-called elastic regime. Micromechanisms of microplasticity will be presented in this paper for a metastable {beta} Ti-15V-3Cr-3Al-3Sn (Ti-15-3) alloy deformed in incremental stages to failure under monotonic loading. Micromechanisms of tensile deformation and fracture will be elucidated for a Ti-15-3 plate with single phase {beta} and Widmanstaetten {alpha}+{beta} microstructures.

  5. Constraints on Thermal Evolution of Mars from Relaxation Models of Crustal and Topographic Dichotomy

    NASA Technical Reports Server (NTRS)

    Guest, A.; Smrekar, S. E.

    2005-01-01

    The early thermal evolution of Mars is largely unconstrained. Models such as degree one convection [1,2,3], plate tectonics [4], and a transition to stagnant lid [5] have been proposed to explain formation of the dichotomy, the Tharsis rise, crustal production, and dynamo evolution. Here we model both the early deformation of the dichotomy and the long-term preservation as a means of examining the plausibility of a range of early thermal evolution models. Constraints include the preservation of crustal thickness and topographic differences between the northern and southern hemispheres and the geologic history of the dichotomy [6]). Our previous modeling indicates that the lower crust must have been weak enough to allow for relaxation early on, but the Martian interior had to cool fast enough to preserve the crustal difference and the associated topographic difference (5 km) over approx. 3-3.5 Gyr [7].

  6. Development of large scale production of Nd-doped phosphate glasses for megajoule-scale laser systems

    SciTech Connect

    Ficini, G.; Campbell, J.H.

    1996-05-01

    Nd-doped phosphate glasses are the preferred gain medium for high-peak-power lasers used for Inertial Confinement Fusion research because they have excellent energy storage and extraction characteristics. In addition, these glasses can be manufactured defect-free in large sizes and at relatively low cost. To meet the requirements of the future mega-joule size lasers, advanced laser glass manufacturing methods are being developed that would enable laser glass to be continuously produced at the rate of several thousand large (790 x 440 x 44 mm{sup 3}) plates of glass per year. This represents more than a 10 to 100-fold improvement in the scale of the present manufacturing technology.

  7. Emissions of metals, chromium and nickel species, and organics from municipal waste-water-sludge incinerators. Volume 9. Site 9 emission-test report: Appendices. Final report, 1989-91

    SciTech Connect

    Segall, R.R.; DeWees, W.G.; Lewis, F.M.

    1992-03-01

    Site 9 is a secondary plant designed for 15 million gallons per day (MGD) of wastewater flow. The sludge incinerator at Site 9 is a seven (7) hearth, multiple hearth furnace (MHF) built by Nichols Engineering in 1974 controlled by an adjustable throat venturi scrubber with a nominal pressure drop of 20 in. w.c.. After leaving the venturi, the gases pass upward through a three (3) plate tray scrubber with a Chevron mist eliminator. A 10 ft. x 10 ft., upflow, wet electrostatic precipitator, manufacturer testing. Volume 9 contains the appendices PB92-151620 for Volume 8. These include: (1) Incinerator and Scrubber Operating Data, (2) Sampling and Analytical Methods; (3) Sample Calculations; (4) Analytical Data and Reports; (5) Continuous Emission Monitoring Data, Calibrations/One-min Averages, and (6) External Audit Report.

  8. Project environmental microbiology as related to planetary quarantine

    NASA Technical Reports Server (NTRS)

    Pflug, I. J.

    1974-01-01

    Microbiological analyses of soil particles allow for the following conclusions: (1) there is a considerable range in the values of aerobic, mesophilic microbial counts associated with different size soil fractions; (2) as soil particle size increases, there is an increase in the mean microbial concentration per particle; (3) plate counts of aerobic, mesophilic organisms in unheated soils yielded a mean concentration of about six organisms per particle for the smallest soil fraction; (4) aerobic, mesophilic counts for sonicated particles heated at 80 C for 20 minutes yielded mean values of about two organisms per particle for the smallest particles; (5) some actinomycetes associated with the soil fractions could survive dry heat treatment at 110 C for one hour; and (6) soil particles stored under ambient laboratory conditions for 2.5 years aerobic, mesophilic plate counts which were comparable or slightly greater than the counts for more recently collected soil.

  9. Freestanding GaN-based light-emitting diode membranes on Y3Al5O12:Ce3+ crystal phosphor plate for efficient white light emission

    NASA Astrophysics Data System (ADS)

    Feng, Lungang; Li, Yufeng; Xiong, Han; Wang, Shuai; Wang, Jiangteng; Ding, Wen; Zhang, Ye; Yun, Feng

    2016-08-01

    GaN-based light-emitting diode (LED) membranes were peeled from the substrate using electrochemical etching of the bottom sacrificial layer. The freestanding membranes were transferred onto a Y3Al5O12:Ce3+ (YAG:Ce3+) crystal phosphor plate to realize a compact white light source. Verified by the Raman test, the initial strain within the original GaN layers was greatly released after the exfoliation process, which induced alleviation of the quantum confined stark effect. The electroluminescence measurement of a blue LED membranes-on-YAG:Ce3+ plate-structured device was conducted exhibiting color coordinates and a correlated color temperature of (0.3367,0.4525) and 5450 K at 10 mA, respectively.

  10. Acoustic Plate Mode sensing in liquids based on free and electrically shorted plate surfaces.

    PubMed

    Anisimkin, V I; Caliendo, C; Verona, E

    2016-05-01

    The sensing behavior to liquids for Acoustic Plate Modes (APMs) propagating along 64°Y, 90°X LiNbO3 plate was investigated vs. two electric boundary conditions. The changes in the APMs phase velocity and attenuation were measured upon exposure to different liquids wetting one of the surfaces of the plate, either free or electrically shorted by a thin conductive Al layer. The experimental data confirm that the presence of a metallic layer covering one of the plate surfaces affects the viscosity and temperature sensitivity of the device. The differences between the sensor response for various liquids, with free or metalized faces, are interpreted in terms of the APM polarization. PMID:26901669

  11. Dual fuel gradients in uranium silicide plates

    SciTech Connect

    Pace, B.W.

    1997-08-01

    Babcock & Wilcox has been able to achieve dual gradient plates with good repeatability in small lots of U{sub 3}Si{sub 2} plates. Improvements in homogeneity and other processing parameters and techniques have allowed the development of contoured fuel within the cladding. The most difficult obstacles to overcome have been the ability to evaluate the bidirectional fuel loadings in comparison to the perfect loading model and the different methods of instilling the gradients in the early compact stage. The overriding conclusion is that to control the contour of the fuel, a known relationship between the compact, the frames and final core gradient must exist. Therefore, further development in the creation and control of dual gradients in fuel plates will involve arriving at a plausible gradient requirement and building the correct model between the compact configuration and the final contoured loading requirements.

  12. Effects of intermetallic particles on the SCC initiation of zirconium alloys

    NASA Astrophysics Data System (ADS)

    Kubo, T.; Wakashima, Y.; Imahashi, H.; Nagai, M.

    1985-06-01

    In order to investigate effects of intermetallic particles on SCC initiation of zirconium alloys, tensile tests were conducted in an iodine atmosphere using zirconium plates with different amounts of impurities, and Zircaloy-2 plates. SCC susceptibility of zirconium increased significantly with its iron content. Even small amounts of iron could form the intermetallic compound ZrFe 2 whose particle size and number increased with iron content. In the case of Zircaloy-2, two different types of ternary compounds were detected, namely Zr(CrFe) 2 and Zr 2(NiFe). Metallographic examinations showed that the particles located at grain boundaries were important sites of SCC initiation in zirconium alloys. The initiation probability increased significantly with the amount of the particles, which supported the strong correlation between SCC susceptibility of zirconium and its iron content.

  13. Effects of crystallographic orientation on plastic deformation and SCC initiation of zirconium alloys

    NASA Astrophysics Data System (ADS)

    Kubo, T.; Wakashima, Y.; Amano, K.; Nagai, M.

    1985-05-01

    In order to investigate the effects of crystallographic orientation on deformation and crack initiation in iodine-induced SCC of zirconium alloys, uniaxial tensile tests of zirconium and Zircaloy-2 plates were conducted in an iodine atmosphere. The crystallographic orientation of individual grains was determined by an etch-pit technique prior to testing. After testing, the etch-pit technique showed that prismatic slip was predominant in the plastic deformation and that cleavage cracks extended along basal planes. The plastic deformation of individual grains was significantly influenced by their crystallographic orientations, which varied from one grain to another. Accordingly, inhomogeneous plastic deformation occurred between grains. The crack initiation took place preferentially at grain boundaries where differences of crystallographic orientations were large between adjacent grains. This indicated that crack initiations was caused by stress concentration due to strain incompatibility at those grain boundaries.

  14. Fabrication and application of a wireless inductance-capacitance coupling microsensor with electroplated high permeability material NiFe

    NASA Astrophysics Data System (ADS)

    Chen, Y. H.; Chang, H. C.; Lai, C. C.; Chang, I. N.

    2011-01-01

    A fully integrated wireless inductance-capacitance (LC) coupling microsensor was designed and fabricated by MEMS technology. The sensing loop was formed by connecting a deformable parallel-plated capacitor and a planar spiral inductor with a Ni(80)Fe(20) core. Polyimide and PMMA were used to isolate and package the devices. Typical dimension of the sensors was 5 × 5 mm2 × 0.77 mm. Different electroplated inductive coils (30, 40, and 60 turns) were fabricated to connect with a 4 × 4 mm2 plate capacitor in series. The LC sensing module for measuring liquid-level induced frequency responses was setup. Experimental results show that frequency response decreased as liquid level increased and sensitivity is about 7.01 kHz/cm with deviation less than 2%. Developed planar spiral inductor with high permeability magnetic core can provide a wide range of frequency variation in LC sensing applications.

  15. Electrocaloric effect of metal-insulator transition in VO{sub 2}

    SciTech Connect

    Matsunami, Daichi; Fujita, Asaya

    2015-01-26

    The electrocaloric effect was observed in association with an electric-field induced metal-insulator transition in VO{sub 2} using a calorimetric measurement under an applied voltage. For a VO{sub 2} plate with a 0.4 mm thickness located in the center of a capacitor-like structure, the metal-insulator transition was manipulated by applying a few volts. The occurrence of a transition in such a thick sample with relatively low voltage indicates that a surface charge accumulation mechanism is effective. The isothermal entropy change reached 94 J kg{sup −1} K{sup −1}, while the adiabatic temperature change was calculated as −3.8 K under a voltage change of 0–3 V. The large entropy change is attributed to correlation of the complex freedom among spin, charge, and lattice.

  16. Cycloid kinematics of relative plate motion

    SciTech Connect

    Cronin, V.S.

    1987-11-01

    The trajectory of a point on one plate as observed from another plate is generally a complex curve and not a small circle around a single axis of relative motion, as is commonly assumed. The shape of the relative-motion path is given the general name spherical cycloid because of its morphological similarity to cycloid planetary trajectories described by early astronomers. The cycloid relative-motion model predicts that the following phenomena occur during finite displacements: (1) the relative velocity and the curvature of the trajectory of a point on one plate relative to another plate varies systematically; (2) plates wobble relative to one another; and (3) the angle of convergence and/or divergence varies systematically along the length of any given transform fault. The small-circle relative-motion model, whereby transform faults have been considered lines of pure slip along which crust is conserved, is not generally valid for finite relative displacements.

  17. Human placental coated vesicles contain receptor-bound transferrin.

    PubMed Central

    Booth, A G; Wilson, M J

    1981-01-01

    Human placental coated vesicles have been purified by a method involving sucrose-density-gradient centrifugation and treatment with wheat-germ agglutinin. These preparations were free of contamination by placental microvillus fragments. Crossed immunoelectrophoresis demonstrated that the coated vesicles contained a single serum protein, which was identified as transferrin. This transferrin was only observed after the vesicles were treated with a non-ionic detergent, and its behaviour during crossed hydrophobic-interaction immunoelectrophoresis suggested that a large proportion of it was receptor-bound. No other serum proteins, including immunoglobulin G, could be detected in these preparations. Receptor-bound transferrin was the only antigen common to placental coated vesicles and microvilli, implying that other plasma-membrane proteins are excluded from the region of membrane involved in coated-vesicle formation. Images PLATE 2 PLATE 1 Fig. 1. Fig. 2. Fig. 3. PMID:6272755

  18. Improvement of localised corrosion resistance of AISI 2205 Duplex Stainless Steel joints made by gas metal arc welding under electromagnetic interaction of low intensity

    NASA Astrophysics Data System (ADS)

    García-Rentería, M. A.; López-Morelos, V. H.; García-Hernández, R.; Dzib-Pérez, L.; García-Ochoa, E. M.; González-Sánchez, J.

    2014-12-01

    The resistance to localised corrosion of AISI 2205 duplex stainless steel plates joined by Gas Metal Arc Welding (GMAW) under the effect of electromagnetic interaction of low intensity (EMILI) was evaluated with sensitive electrochemical methods. Welds were made using two shielding gas mixtures: 98% Ar + 2% O2 (M1) and 97% Ar + 3% N2 (M2). Plates were welded under EMILI using the M1 gas with constant welding parameters. The modified microstructural evolution in the high temperature heat affected zone and at the fusion zone induced by application of EMILI during welding is associated with the increase of resistance to localised corrosion of the welded joints. Joints made by GMAW using the shielding gas M2 without the application of magnetic field presented high resistance to general corrosion but high susceptibility to undergo localised attack.

  19. The composite of nitrogen-doped anatase titania plates with exposed {001} facets/graphene nanosheets for enhanced visible-light photocatalytic activity.

    PubMed

    Shi, Jian-Wen; Ai, Hui-Ying; Chen, Jian-Wei; Cui, Hao-Jie; Fu, Ming-Lai

    2014-09-15

    Composite photocatalysts composed of nitrogen-doped anatase TiO2 plates with exposed {001} facets (NTS) and graphene nanosheets (G) were firstly synthesized by a facile one-pot hydrothermal process. The morphologies, structural properties, and photocatalytic activities of the resultant NTS/G composites were investigated in detail. Graphene nanosheets were demonstrated play three important roles in the NTS/G composites, as transporter of photo-excited electrons, extender of light absorption range and enhancer of adsorptive capacity, respectively. Due to the effective charge anti-recombination, the efficient utilization of the visible light and the high adsorptive capacity to target pollutants, the composites exhibited significant improvement in photocatalytic degradation of methylene blue under visible light irradiation. Based on the results, the mechanism of enhanced visible-light photocatalytic activity on NTS/G composites was proposed. PMID:24998060

  20. Four mass coupled oscillator guitar model.

    PubMed

    Popp, John E

    2012-01-01

    Coupled oscillator models have been used for the low frequency response (50 to 250 Hz) of a guitar. These 2 and 3 mass models correctly predict measured resonance frequency relationships under various laboratory boundary conditions, but did not always represent the true state of a guitar in the players' hands. The model presented has improved these models in three ways, (1) a fourth oscillator includes the guitar body, (2) plate stiffnesses and other fundamental parameters were measured directly and effective areas and masses used to calculate the responses, including resonances and phases, directly, and (3) one of the three resultant resonances varies with neck and side mass and can also be modeled as a bar mode of the neck and body. The calculated and measured resonances and phases agree reasonably well. PMID:22280705

  1. High temporal resolution measurements of linear polarization in solar flare's Hα line.

    NASA Astrophysics Data System (ADS)

    Kotrč, P.

    Since the summer season 1998 a system consisting of a Wollaston prism and λ/2 plate is experimentally tested in the complex of video cameras used both in the image and in the spectral data acquisition of the Ondřejov Multichannel Flare Spectrograph. In addition to the slit-jaw camera and to the three other video cameras working in Hα, Hβ (resp. in He D3) and in the Ca II 854.2 nm another CCD video camera for measurements of linear polarization in Hα spectral line has been added. The main purpose of this set of fast detectors is to observe solar flare spectra and images and to detect fast variations of intensity and linear polarization expected at the beginning and during initial phases of solar flares. Main advantages and limitations of the system are briefly described from the points of view of its scientific philosophy, intends and outputs. Some obtained results, experience and future prospects are discussed.

  2. Preliminary neutronics calculations for conversion of the Tehran research reactor core from HEU to LEU fuel

    SciTech Connect

    Nejat, S.M.R. . Dept. of Engineering Physics.)

    1993-08-01

    The 5-MW highly enriched uranium (HEU)-fueled Tehran Research Reactor is considered for conversion to high-density, low-enriched uranium (LEU) fuel. A preliminary neutronics calculation is performed as part of the conversion goal. In this study, two cores are considered: the HEU reference core and a proposed LEU core similar to the reference core, and a proposed LEU core similar to the reference core, using standardized U[sub 3]Si[sub 2] plates with the option of different [sup 235]U loadings. Various possibilities are investigated for the conversion of HEU to LEU fuel elements with 20% enriched [sup 235]U loadings of 207 to 297 g [sup 235]U/element. For the same equilibrium cycle length, the fuels are compared for flux, power distribution, burnup, and reactivity.

  3. Note: Comparative experimental studies on the performance of 2-2 piezocomposite for medical ultrasound transducers.

    PubMed

    Marinozzi, F; Bini, F; Biagioni, A; Grandoni, A; Spicci, L

    2013-09-01

    The paper reports the experimental investigation of the behavior of 2-2 Lead Zirconate Titanate (PZT)-polymer composite transducers array for clinical ultrasound equipments. Several 2-2 plate composites having the same dicing pitch of 0.11 mm and different volume fractions were manufactured and investigated. Measurements were performed through different techniques such as electrical impedance, pulse-echo, and Laser Doppler Vibrometer. With the last one, maps of the surface displacement were presented relative to thickness mode and first lateral mode resonance frequencies. The transducers with volume fractions of the 40% resulted markedly inefficient, whereas the largest bandwidth and best band shape were achieved by the 50%. PMID:24089885

  4. Crystallization Behavior of Magnesium Salts:. a Summary of Some Experimental Observations

    NASA Astrophysics Data System (ADS)

    Xue, Dongfeng; Zou, Longjiang; Wang, Lei; Yan, Xiaoxing

    Some efficient methods have been developed to chemically prepare some magnesium salt products with multiscale morphologies such as MgCO3·3H2O and 5Mg(OH)2·MgSO4·2H2O whiskers, Mg5(CO3)4(OH)2·4H2O microplates and aggregates, and Mg(OH)2 plates and spheres. The crystallization processes of the as-prepared products were studied by designing different reaction routes and corresponding growth morphologies. In these solution chemical systems, Mg2+ cation was found to be easily coordinated by various ligands, and can be easily transformed into various compounds with variable compositions. The current crystallization observations of some magnesium salts can be readily simulated by the chemical bonding theory of single crystal growth. These results can guide the further studies of various magnesium salts with controllable morphologies.

  5. Irradiation performance of reduced-enrichment fuels tested under the US RERTR program

    SciTech Connect

    Snelgrove, J.L.; Hofman, G.L.; Copeland, G.L.

    1985-01-01

    Considerable progress in the irradiation testing of high-density, reduced-enrichment fuels has been made during the past year. Miniplates containing UA1, U/sub 3/Si/sub 2/, U/sub 3/Si/sub 1.5/, U/sub 3/Si, U/sub 3/SiCu, and, U/sub 6/Fe have been irradiated. Postirradiation examinations have revealed that breakway swelling has occurred in 6.4-Mg U/m/sup 3/ U/sub 3/Si plates at approx.2.8 x 10/sup 27/ fissions/m/sup 3/. U/sub 3/Si/sub 2/ plates are continuing to show satisfactory performance. The testing of full-sized fuel elements in the ORR and the SILOE reactor have continued with good results. Postirradiation examinations are confirming the satisfactory performance of these elements.

  6. A predictive model for corrosion fatigue crack growth rates in RPV steels exposed to PWR environments

    SciTech Connect

    Atkinson, J.D.; Chen, Z.; Yu, J.

    1995-12-31

    Corrosion fatigue crack propagation rates have been measured in A533B Class 1 plate in stagnant PWR primary water for a range of steel sulphur contents, temperature and corrosion potential values. Parametric descriptions of the data collected under constant rig conditions give good correlations for each variable and are consistent with a crack tip environment controlled process related to sulphur chemistry. A modified crack velocity equation is proposed to include temperature, sulphur content, polarization potential, frequency and {Delta}K values and it is shown how the predictions compare with the proposed ASME XI revision. Critical fatigue situations are identified for 0.003% and 0.019% sulphur steels typical of modern and old plant. The use of the equation in assessing the synergistic effect of variables is discussed.

  7. Phospholipid turnover in Torpedo marmorata electric organ during discharge in vivo.

    PubMed Central

    Bleasdale, J E; Hawthorne, J N; Widlund, L; Heilbronn, E

    1976-01-01

    One electric organ of anaesthetized Torpedo marmorata was stimulated through electrodes placed on the electric lobe of the brain. Nerves to the other electric organ were cut to provide an unstimulated control. Glucose 6-[32P]phosphate was injected into each organ 16h before electrical stimulation. After stimulation for 10 min at 5 Hz, the organs were removed homogenized and centrifuged on a density gradient for the preparation of subcellular fractions. Stimulation increased the incorporation of 32P into phosphatidate, phosphatidylinositol and phosphatidylcholine. The increased phosphatidate labelling, but not that of the other two lipids, was seen in fractions rich in synaptic vesicles. Stimulation had no effect on ATP labelling. The phosphatidate content of most fractions fell slightly after stimulation, but amounts of other phospholipids were not affected. Images PLATE 1 PLATE 2 PMID:825114

  8. Guided Wave Inspection of Supported Pipe Locations Using Electromagnetic Acoustic Transducers

    NASA Astrophysics Data System (ADS)

    Andruschak, Nicholas

    The goal of the work in this thesis is to develop a rapid and reliable NDT system to detect hidden corrosion at pipe-support interfaces using Electromagnetic Acoustic Transducers (EMATs). Since there are often many support interfaces over a piping run, information is needed on the support interface conditions to optimize subsequent detailed inspections. In this work it is important to be able to isolate the effects produced from the support interface and the incident guided wave. To do this an optimum EMAT operating point is first selected, then the support interfaces and wall loss type defects are independently analyzed through experimentally validated finite element models. It is found that operating the SH1 plate wave mode near the `knee' of its dispersion curve gives a high sensitivity to wall loss type defects while experiencing a minimal effect from the support contact region.

  9. The active transport of 5-hydroxyindol-3-ylacetic acid and 3-methoxy-4-hydroxyphenylacetic acid from a recirculatory perfusion system of the cerebral ventricles of the unanaesthetized dog

    PubMed Central

    Ashcroft, G. W.; Dow, R. C.; Moir, A. T. B.

    1968-01-01

    1. An operation on dogs for the implantation of guide tubes to the lateral ventricle and cisterna magna and a method whereby the ventricular space can be repeatedly perfused in conscious and unrestrained animals are described. 2. The characteristics of a recirculatory perfusion system were examined and the bulk formation and absorption of cerebrospinal fluid and the volume of the ventricular space perfused were derived from the concentrations achieved during the infusion of inulin into the system. 3. 5-hydroxyindol-3-ylacetic acid (5-HIAA), the acid metabolite of 5-hydroxytryptamine, and 3-methoxy-4-hydroxyphenylacetic acid (HVA), the main acid metabolite of dopamine, were demonstrated to be mainly removed from cerebrospinal fluid (c.s.f.) by an active transport system localized in the region of the fourth ventricle. 4. It was possible to inhibit the active transport of these acids from cerebrospinal fluid by pre-treating the dogs with probenecid. ImagesPlate 1Plate 2 PMID:5723518

  10. Characterization of the Oxidation State of 229 Th Recoils Implanted in MgF2 for the Search of the Low-lying 229 Th Isomeric State

    NASA Astrophysics Data System (ADS)

    Barker, Beau; Meyer, Edmund; Schacht, Mike; Collins, Lee; Wilkerson, Marianne; Zhao, Xinxin

    2016-05-01

    The low-lying (7.8 eV) isomeric state in 229 Th has the potential to become a nuclear frequency standard. 229 Th recoils from 233 U decays have been collected in MgF2 for use in the direct search of the transition. Of interest is the oxidation state of the implanted 229 Th atoms as this can have an influence on the decay mechanisms and photon emission rate. Too determine the oxidation state of the implanted 229 Th recoils we have employed laser induced florescence (LIF), and plan-wave pseudopotential DFT calculations to search for emission from thorium ions in oxidation states less than + 4. Our search focused on detecting emission from Th3+ ions. The DFT calculations predicted the Th3+ state to be the most likely to be present in the crystal after Th4+. We also calculated the band structure for the Th3+ doped MgF2 crystal. For LIF spectra a number of excitation wavelengths were employed, emission spectra in the visible to near-IR were recorded along with time-resolved emission spectra. We have found no evidence for Th3+ in the MgF2 plates. We also analyzed the detection limit of our apprentice and found that the minimum number of Th3+ atoms that we could detect is quite small compared to the number of implanted 229 Th recoils. The number of implanted 229 Th recoils was derived from a γ-ray spectrum by monitoring emission from the daughters of 228 Th. These were present in the MgF2 plates due to a 232 U impurity, which decays to 228 Th, in the source. LA-UR-16-20442.

  11. Formation of fine {gamma} grain structure through fine {alpha}{sub 2}/{gamma} lamellar structure in Ti-rich TiAl alloy

    SciTech Connect

    Kumagai, T.; Abe, E.; Nakamura, M.

    1997-12-31

    Microstructural development of an extremely fine {alpha}{sub 2}-Ti{sub 32}Al/{gamma}-TiAl lamellar structure, which was formed by ice water quenching after solution-treatment in a high-temperature {alpha}-Ti phase field for a long period of time, was examined during isothermal treatment. In an as-quenched Ti-48at.%Al alloy, the massively transformed {gamma} ({gamma}{sub m}) and untransformed (meaning massively untransformed) fine {alpha}{sub 2}/{gamma} lamellar regions were observed. Fine {gamma} grains, which were similar to {gamma}{sub m}, were generated both within the fine {alpha}{sub 2}/{gamma} lamellae and at the boundary area between the {gamma}{sub m} and the fine {alpha}{sub 2}/{gamma} lamellar regions by aging at low-temperature (1,173 K) for a short time (180s). Further aging (1.8ks) caused the coarsening of these newly generated fine {gamma} grains. On the other hand, the coarsening of the {gamma} grains occurred by a high-temperature (1,323 K) aging treatment even for 180s. Fine {alpha}{sub 2} plates and particles, which were aligned to a particular direction, were observed in the {gamma} grain interiors, indicating that the newly generated {gamma} grains grew at the expense of the fine {alpha}{sub 2}/{gamma} lamellae. It can be considered that the {gamma} grain formation through the fine {alpha}{sub 2}/{gamma} lamellae is closely related to the {alpha}{sub 2}{yields}{gamma} reaction of the {alpha}{sub 2} plates sandwiched by the {gamma} plates, and needs the fast heating rate enough to overcome the {alpha}{sub 2}/{gamma}{yields}{gamma}/{gamma} lamellae reaction.

  12. Changes in wetting properties of alumina surface treated with DPPC in the presence of phospholipase A2 enzyme.

    PubMed

    Wiącek, Agnieszka Ewa

    2011-10-01

    Wetting properties of commercial Al(2)O(3) plates contacted with dipalmitoylphosphatidylcholine (DPPC) or DPPC+enzyme (phospholipase PLA(2)) in NaCl solution were determined by thin layer wicking and with the help of Washburn equation. Van Oss et al.'s approach to interfacial free energy interactions was applied to determining the solid surface free energy components. Wicking experiments were performed both for bare and alumina plates precontacted overnight with the probe liquid saturated vapours, as well as the untreated and DPPC (or DPPC+PLA(2)) treated alumina plates. For this purpose the penetration rates of n-octane, water and formamide were measured. From these experiments it resulted that original alumina surface is strongly polar with electron-donor interactions originating from the surface hydroxyl groups. Adsorption of DPPC on Al(2)O(3) plates slightly increased the hydrophobic character of the alumina surface (considerable decrease of the electron-donor, γ(s)(-) parameter and γ(s)(AB) component was visible) in such a way that the hydrocarbon chains were directed outwards and the polar part towards the alumina surface. However, after the enzyme action the products of DPPC hydrolysis by PLA(2) (palmitic acid and lysophosphatidylcholine) increased again the hydrophilic character of Al(2)O(3) surface (a minor increase in γ(s)(AB) component and drastic increase of the electron-donor γ(s)(-) parameter was noticeable). After treatment with DPPC or DPPC+enzyme PLA(2) solution the changes of the total surface free energy of alumina and its Lifshits-van der Waals (γ(s)(LW)) component were in the range 7-10 mJ/m(2), but the most considerable and delivering more interesting information were the changes of the electron-donor (γ(s)(-)) parameter ranging from 27 to 35 mJ/m(2). Moreover, the changes of the alumina surface wettability were dependent on the time of the enzyme contacting with DPPC in NaCl solution. On the basis of the obtained results it seems that

  13. Sheath structure transition controlled by secondary electron emission

    NASA Astrophysics Data System (ADS)

    Schweigert, I. V.; Langendorf, S. J.; Walker, M. L. R.; Keidar, M.

    2015-04-01

    In particle-in-cell Monte Carlo collision (PIC MCC) simulations and in an experiment we study sheath formation over an emissive floating Al2O3 plate in a direct current discharge plasma at argon gas pressure 10-4 Torr. The discharge glow is maintained by the beam electrons emitted from a negatively biased hot cathode. We observe three types of sheaths near the floating emissive plate and the transition between them is driven by changing the negative bias. The Debye sheath appears at lower voltages, when secondary electron emission is negligible. With increasing applied voltage, secondary electron emission switches on and a first transition to a new sheath type, beam electron emission (BEE), takes place. For the first time we find this specific regime of sheath operation near the floating emissive surface. In this regime, the potential drop over the plate sheath is about four times larger than the temperature of plasma electrons. The virtual cathode appears near the emissive plate and its modification helps to maintain the BEE regime within some voltage range. Further increase of the applied voltage U initiates the second smooth transition to the plasma electron emission sheath regime and the ratio Δφs/Te tends to unity with increasing U. The oscillatory behavior of the emissive sheath is analyzed in PIC MCC simulations. A plasmoid of slow electrons is formed near the plate and transported to the bulk plasma periodically with a frequency of about 25 kHz.

  14. A Six-Node Curved Triangular Element and a Four-Node Quadrilateral Element for Analysis of Laminated Composite Aerospace Structures

    NASA Technical Reports Server (NTRS)

    Martin, C. Wayne; Breiner, David M.; Gupta, Kajal K. (Technical Monitor)

    2004-01-01

    Mathematical development and some computed results are presented for Mindlin plate and shell elements, suitable for analysis of laminated composite and sandwich structures. These elements use the conventional 3 (plate) or 5 (shell) nodal degrees of freedom, have no communicable mechanisms, have no spurious shear energy (no shear locking), have no spurious membrane energy (no membrane locking) and do not require arbitrary reduction of out-of-plane shear moduli or under-integration. Artificial out-of-plane rotational stiffnesses are added at the element level to avoid convergence problems or singularity due to flat spots in shells. This report discusses a 6-node curved triangular element and a 4-node quadrilateral element. Findings show that in regular rectangular meshes, the Martin-Breiner 6-node triangular curved shell (MB6) is approximately equivalent to the conventional 8-node quadrilateral with integration. The 4-node quadrilateral (MB4) has very good accuracy for a 4-node element, and may be preferred in vibration analysis because of narrower bandwidth. The mathematical developments used in these elements, those discussed in the seven appendices, have been applied to elements with 3, 4, 6, and 10 nodes and can be applied to other nodal configurations.

  15. Contribution to the large and stable electric field induced strain for textured Pb(Mg1/3Nb2/3)0.675Ti0.325O3 ceramics

    NASA Astrophysics Data System (ADS)

    Zeng, Jiangtao; Zhao, Kunyu; Ruan, Wei; Ruan, Xuezheng; Zheng, Liaoying; Li, Guorong

    2016-08-01

    Textured Pb(Mg1/3Nb2/3)0.675Ti0.325O3 (PMN-PT) ceramics were prepared by the templated grain growth method with 3% plate-like BaTiO3 as templates. The degree of grain orientation was about 81% by calculating from the XRD pattern. Temperature dependence of electric field induced strain was measured for both untextured and textured PMN-PT ceramics. The results show that the electric field induced strain for textured PMN-PT ceramics is much larger and more stable than that for untextured PMN-PT ceramics in a wide temperature range. The contribution from the piezoelectric effect and electrostrictive effect to the strain was analyzed, and it was found that textured PMN-PT ceramics exhibited electrostrictive coefficient Q33 as high as 5.19 × 10-2 m4 C-2 and it was comparable to that of PMN-PT single crystals. The electrostrictive effect contributed the main part of the enhancement of electric field induced strain for textured PMN-PT ceramics.

  16. In situ synthesis of CdS/CdWO4/WO3 heterojunction films with enhanced photoelectrochemical properties

    NASA Astrophysics Data System (ADS)

    Zhan, Faqi; Li, Jie; Li, Wenzhang; Yang, Yahui; Liu, Wenhua; Li, Yaomin

    2016-09-01

    CdS/CdWO4/WO3 heterojunction films on fluorine-doped tin oxide (FTO) substrates are for the first time prepared as an efficient photoanode for photoelectrochemical (PEC) hydrogen generation by an in situ conversion process. The samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet visible spectrometry (UV-vis) and X-ray photoelectron spectroscopy (XPS). The CdS hollow spheres (∼80 nm) sensitized WO3 plate film with a CdWO4 buffer-layer exhibits increased visible light absorption and a significantly improved photoelectrochemical performance. The photocurrent density at 0 V (vs. Ag/AgCl) of the CdS/CdWO4/WO3 anode is ∼3 times higher than that of the CdWO4/WO3 anode, and ∼9 times higher than that of pure WO3 under illumination. The highest incident-photon-to-current-efficiency (IPCE) value increased from 16% to 63% when the ternary heterojunction was formed. This study demonstrates that the synthesis of ternary composite photocatalysts by the in situ conversion process may be a promising approach to achieve high photoelectric conversion efficiency.

  17. High power continuous-wave titanium:sapphire laser

    DOEpatents

    Erbert, G.V.; Bass, I.L.; Hackel, R.P.; Jenkins, S.L.; Kanz, V.K.; Paisner, J.A.

    1993-09-21

    A high-power continuous-wave laser resonator is provided, wherein first, second, third, fourth, fifth and sixth mirrors form a double-Z optical cavity. A first Ti:sapphire rod is disposed between the second and third mirrors and at the mid-point of the length of the optical cavity, and a second Ti:sapphire rod is disposed between the fourth and fifth mirrors at a quarter-length point in the optical cavity. Each Ti:sapphire rod is pumped by two counter-propagating pump beams from a pair of argon-ion lasers. For narrow band operation, a 3-plate birefringent filter and an etalon are disposed in the optical cavity so that the spectral output of the laser consists of 5 adjacent cavity modes. For increased power, seventy and eighth mirrors are disposed between the first and second mirrors to form a triple-Z optical cavity. A third Ti:sapphire rod is disposed between the seventh and eighth mirrors at the other quarter-length point in the optical cavity, and is pumped by two counter-propagating pump beams from a third pair of argon-ion lasers. 5 figures.

  18. High power continuous-wave titanium:sapphire laser

    DOEpatents

    Erbert, Gaylen V.; Bass, Isaac L.; Hackel, Richard P.; Jenkins, Sherman L.; Kanz, Vernon K.; Paisner, Jeffrey A.

    1993-01-01

    A high-power continuous-wave laser resonator (10) is provided, wherein first, second, third, fourth, fifth and sixth mirrors (11-16) form a double-Z optical cavity. A first Ti:Sapphire rod (17) is disposed between the second and third mirrors (12,13) and at the mid-point of the length of the optical cavity, and a second Ti:Sapphire rod (18) is disposed between the fourth and fifth mirrors (14,15) at a quarter-length point in the optical cavity. Each Ti:Sapphire rod (17,18) is pumped by two counter-propagating pump beams from a pair of argon-ion lasers (21-22, 23-24). For narrow band operation, a 3-plate birefringent filter (36) and an etalon (37) are disposed in the optical cavity so that the spectral output of the laser consists of 5 adjacent cavity modes. For increased power, seventy and eighth mirrors (101, 192) are disposed between the first and second mirrors (11, 12) to form a triple-Z optical cavity. A third Ti:Sapphire rod (103) is disposed between the seventh and eighth mirrors (101, 102) at the other quarter-length point in the optical cavity, and is pumped by two counter-propagating pump beams from a third pair of argon-ion lasers (104, 105).

  19. Photoactive Metal-Organic Framework and Its Film for Light-Driven Hydrogen Production and Carbon Dioxide Reduction.

    PubMed

    Wu, Pengyan; Guo, Xiangyang; Cheng, Linjuan; He, Cheng; Wang, Jian; Duan, Chunying

    2016-08-15

    The design of a new photocatalytic system and integrating the essential components in a structurally controlled manner to create artificially photosynthetic systems is high desirable. By incorporating a photoactive triphenylamine moiety to assemble a Gd-based metal-organic framework as a heterogeneous photosensitizer, new artificial systems were constructed for the proton and carbon dioxide reduction under irradiation. The assembled MOFs exhibited a one-dimensional metal-oxygen pillar that was connected together by the depronated TCA(3-) ligands to form a three-dimensional noninterpenetrating porous framework. The combining of proton reduction and/or the carbon dioxide reduction catalysts, i.e., the Fe-Fe hydrogenase active site models and the Ni(Cyclam) complexes, initiated a photoinduced single electron transfer from its excited state to the substrate. The system exhibited an initial TOF of 320 h(-1) of hydrogen per catalyst and an overall quantum yield of about 0.21% and is able to reduce carbon dioxide under irradiation. The deposit of the photoactive Gd-TCA into the film of an α-Al2O3 plate provided a platform for the practical applications through prolonging the lifetime of the artifical system and allowed the easily operated devices being recyclable as a promising photocatalytic system. PMID:27479135

  20. Tunable filters using wideband elastic resonators.

    PubMed

    Kadota, Michio; Ogami, Takashi; Kimura, Tetsuya; Daimon, Katsuya

    2013-10-01

    Currently, an ultra-wideband resonator is greatly needed to realize a tunable filter with a wide tunable range, because mobile phones with multiple bands and cognitive radio systems require such tunable filters to simplify their circuits. Although tunable filters have been studied using SAW resonators, their tunable range was insufficient for the filters even when wideband SAW resonators with a bandwidth of 17% were used. Therefore, the fabrication of wider-bandwidth resonators has been attempted with the goal of realizing tunable filters with wide tunable ranges. In this study, an SH0- mode plate wave resonator in a 27.5°YX-LiNbO3 plate with an ultra-wide bandwidth of 29.1%, a high impedance ratio of 98 dB, and a high Q (Q(r) = 700 and Q(a) = 720) was realized. Two types of tunable filters were constructed using such SH0-mode resonators and capacitors. As a result, tunable ranges (bands) of 13% to 19% were obtained. The possibility of applying the SH0-mode resonator in the high-frequency gigahertz range is discussed. PMID:24081261

  1. Notched Tensile and Impact Fracture of Ti-15-3 Laser Welds

    NASA Astrophysics Data System (ADS)

    Tsay, Leu-Wen; Wu, Yan-Jie; Chen, Chun

    2011-12-01

    The notched tensile strength (NTS) and impact toughness of Ti-15V-3Cr-3Sn-3Al ( β-type titanium alloy Ti-15-3) laser welds aged at temperatures ranging from 590 K to 866 K (317 °C to 593 °C) were determined, and the results were compared to those of unwelded Ti-15-3 plates aged at the same temperature. At a given aging temperature, α precipitates in welded specimens were finer and exhibited higher hardness than those in unwelded specimens. Among the tested specimens, the weld aged at 644 K (371 °C) was most susceptible to notch sensitivity. In those welds aged at or above 755 K (482 °C), the coarse columnar structure was prone to interdendritic fracture during notched tensile tests, which reduced the NTS of the weld relative to that of the unwelded plate aged at an equivalent temperature. Of the tested specimens, the weld that was not subjected to the postweld aging treatment possessed the highest impact toughness among the specimens.

  2. Development of a loop-mediated isothermal amplification assay for the detection of Streptococcus agalactiae in bovine milk.

    PubMed

    Bosward, Katrina L; House, John K; Deveridge, Amber; Mathews, Karen; Sheehy, Paul A

    2016-03-01

    Streptococcus agalactiae is a well-characterized bovine mastitis pathogen that is known to be highly contagious and capable of spreading rapidly in affected dairy herds. Loop-mediated isothermal amplification (LAMP) is a novel molecular diagnostic method that has the capability to provide rapid, cost-effective screening for pathogens to support on-farm disease control and eradication programs. In the current study, a LAMP test was developed to detect S. agalactiae in milk. The assay was validated on a bank of existing clinical mastitis milk samples that had previously been identified as S. agalactiae positive via traditional microbiological culture techniques and PCR. The LAMP assay was conducted on bacterial colonies and DNA extracted from milk in tube- and plate-based formats using multiple detection platforms. The 1-h assay conducted at 64 °C exhibited repeatability (coefficient of variation) of 2.07% (tube) and 8.3% (plate), sensitivity to ~20 pg of extracted DNA/reaction, and specificity against a panel of known bacterial mastitis pathogens. Of the 109 known S. agalactiae isolates assessed by LAMP directly from bacterial cells in culture, 108 were identified as positive, in accordance with PCR analysis. The LAMP analysis from the corresponding milk samples indicated that 104 of these milks exhibited a positive amplification curve. Although exhibiting some limitations, this assay provides an opportunity for rapid screening of milk samples to facilitate on-farm management of this pathogen. PMID:26778303

  3. DSI3D-RCS test case manual

    SciTech Connect

    Madsen, N.; Steich, D.; Cook, G.; Eme, B.

    1995-08-01

    The DSI3D-RCS code is designed to numerically evaluate radar cross sections on complex objects by solving Maxwell`s curl equations in the time-domain and in three space dimensions. The code has been designed to run on the new parallel processing computers as well as on conventional serial computers. The DSI3D-RCS code has been used to solve the following problems: (1) wedge cylinder--thin flat metal plate; (2) wedge cylinder with plate extension--thin flat metal plate; (3) plate with half cylinder extension--thin flat metal plate; (4) rectangular plate (business card)--thin flat metal plate; (5) wedge cylinder with gap--thin flat metal plate; (6) NASA Almond; (7) wavelength circular cavity. In order to generate each of the angle sweeps, it was necessary to run DSI3D once for each data point on the graphs. This is because these are backscatter calculations, and the incident pulse comes from a different direction as the angle {phi} is changed.

  4. Microbial contamination of the environment after the irradiation of Er:YAG laser in infected root canals

    NASA Astrophysics Data System (ADS)

    Brugnera, Aldo, Jr.; Zanin, Fatima A. A.; Sampaio Moura, Marcelo; Heredia Seixas, Fabio; Rodrigues de Araujo Estrela, Cyntia; Estrela, Carlos; Djalma Pecora, Jesus

    2003-06-01

    The purpose of this study was to analyze the environment microbial contamination produced by Er:YAG laser irradiation in infected root canals. A total of 20 human anterior teeth were prepared, sterilized and, then, inoculated with a mixture of the following microorganisms: S. Aureus, E. Faecalis, P. Aeruginosa, B. Subtilis and C. Albicans. After the contamination period (28 days), the teeth were irrigated with sterile distilled water or 1% sodium hypochlorite and, then, irradiated with an Er:YAG laser with two different laser parameters: 52 mJ or 110 mJ output at the fiber tip. Eighteen Petri dishes with 20 ml of BHI Agar were used in the study. For each group, 3 plates with BHIA were used for the analysis of the microbial contamination of the environment during the activation of the laser in infected root canals. The plates were positioned in differing distances away from the irradiated tooth (plate 1 - distance of 15 cm, plate 2 - distance of 50 cm and plate 3 - distance of 3 meters). After the analysis of the results, it was observed that the larger microbial contamination occurred in Group 1 (teeth irrigated with sterile distilled water and irradiated with Er:YAG laser with 52 mJ output at the fiber tip), plate 1 (positioned 15 cm away from the irradiated tooth), with values greater than 30 Colony-Forming Units (CFU).

  5. Compatibility of Ce-TZP/Al2O3 nanocomposite frameworks and veneering porcelains.

    PubMed

    Terui, Yuichi; Sato, Kotaro; Goto, Daisuke; Hotta, Yasuhiro; Tamaki, Yukimichi; Miyazaki, Takashi

    2013-01-01

    The aim of this study was to examine the compatibility of Ce-TZP/Al2O3 nanocomposite (CTA) frameworks and veneering porcelains using the Schwickerath crack initiation test and clarify the effects on debonding/crack initiation strength (DIS) of both surface pretreatment (include heat treatment) of the frameworks, type of veneering porcelain varying the coefficient of thermal expansion (CTE), and surface roughness of the frameworks. The surfaces of Ce-TZP/Al2O3 plates were mechanically treated and followed by post-heat treatment. The liner and body porcelains were built up and fired according to the manufacturer's instructions. Surface analyses of the fractured plates showed compatibility with liner porcelains. Since no statistically difference in the DIS was found amongst the different surface treatments, post-heat treatments don't be mandatory. Whereas, since differences in DIS were found when different porcelains with different CTE were used, we concluded the matching of CTE of the porcelain with that of Ce-TZP/Al2O3 was important for successful all-ceramic restorations using Ce-TZP/Al2O3 frameworks. PMID:24088843

  6. The isolation and partial characterization of the serum lipoproteins and apolipoproteins of the rainbow trout.

    PubMed Central

    Skinner, E R; Rogie, A

    1978-01-01

    1. VLD (very-low-density), LD (low-density) and HD (high-density) lipoproteins were isolated from the serum of trout (Salmo gairdneri Richardson). 2. Each lipoprotein class resembled that of the human in immunological reactivity, electrophoretic behaviour and appearance in the electron microscope. Trout LD lipoprotein, however, was of greater density than human LD lipoprotein. 3. The trout lipoproteins have lipid compositions which are similar to those of the corresponding human components, except for their high contents of long-chain unsaturated fatty acids. 4. HD and LD lipoproteins were immunologically non-identical, whereas LD lipoproteins possessed antigenic determinants in common with VLD lipoproteins. 5. VLD and HD lipoproteins each contained at least seven different apoproteins, whereas LD liprotein was composed largely of a single apoprotein which resembled human apolipoprotein B. 6. At least one, and possibly three, apoprotein of trout HD lipoprotein showed features which resemble human apoprotein A-1.7. The broad similarity between the trout and human lipoprotein systems suggests that both arose from common ancestral genes early in evolutionary history. Images Fig. 2. Fig. 3. PLATE 1 Fig. 4. Fig. 5. Fig. 6. Fig. 8. PMID:100102

  7. A lateral field excited (yxl)88° LiTaO3 bulk acoustic wave sensor with interdigital electrodes.

    PubMed

    Ma, Tingfeng; Wang, Ji; Du, Jianke; Yuan, Lili; Qian, Zhenghua; Zhang, Zhitian; Zhang, Chao

    2013-03-01

    In this work, to improve the sensitivity of lateral field excited (LFE) sensors to changes of liquid conductivity, LFE bulk acoustic wave sensors with interdigital electrodes are investigated. LFE bulk acoustic wave on thickness-shear mode is excited successfully by interdigital electrodes on (yxl)88° LiTaO(3) and applied in liquid-phase sensor. The electric field direction of LFE (yxl)88° LiTaO(3) plates is determined. Based on this, several LFE bulk acoustic wave sensors with interdigital electrodes are designed and fabricated to increase the sensitivity of LiTaO(3) LFE sensors. The results show that the (yxl)88° LiTaO(3) LFE sensor with interdigital electrodes is 10.9 times and 2.1 times more sensitive to changes in liquid conductivity compared to traditional LFE devices with single gap circular electrodes and Archimedes spiral electrodes, respectively. The results are important for investigating high-sensitivity LFE bulk acoustic wave sensors by using LiTaO(3) crystal. PMID:23339996

  8. Er3+ diffusion in LiTaO3 crystal

    NASA Astrophysics Data System (ADS)

    Zhang, De-Long; Zhang, Qun; Wong, Wing-Han; Pun, Edwin Yue-Bun

    2015-12-01

    Some Er3+-doped LiTaO3 plates were prepared by in-diffusion of Er-metal film locally coated onto congruent Z-cut substrate in air at a wide temperature range from 1000 to 1500 °C. After diffusion, Er3+-doping effect on LiTaO3 refractive index and Li2O out-diffusion arising from Er3+ in-diffusion were studied at first. Refractive indices at the doped and undoped surface parts were measured by prism coupling technique and the surface composition was estimated. The results show that Er3+ dopant has small contribution to the LiTaO3 index. Li2O out-diffusion is slight (Li2O content loss <0.3 mol%) for the temperature below 1300 °C while is moderate (Li2O content loss <0.6 mol%) for the temperature above 1400 °C. The Er3+ profile was studied by secondary ion mass spectrometry. The study shows that the diffused Er3+ ions follow either a complementary error function or a Gaussian profile. Characteristic parameters including diffusivity, diffusion constant, activation energy, solubility, solubility constant and heat of solution were obtained and compared with the LiNbO3 case. The comparison shows that the diffusivity and solubility in LiTaO3 are considerably smaller than in LiNbO3 because of the difference of Ta and Nb in atomic weight.

  9. Design and application of a metal wet-etching post-process for the improvement of CMOS-MEMS capacitive sensors

    NASA Astrophysics Data System (ADS)

    Tsai, Ming-Han; Sun, Chih-Ming; Liu, Yu-Chia; Wang, Chuanwei; Fang, Weileun

    2009-10-01

    This study presents a process design methodology to improve the performance of a CMOS-MEMS gap-closing capacitive sensor. In addition to the standard CMOS process, the metal wet-etching approach is employed as the post-CMOS process to realize the present design. The dielectric layers of the CMOS process are exploited to form the main micro mechanical structures of the sensor. The metal layers of the CMOS process are used as the sensing electrodes and sacrificial layers. The advantages of the sensor design are as follows: (1) the parasitic capacitance is significantly reduced by the dielectric structure, (2) in-plane and out-of-plane sensing gaps can be reduced to increase the sensitivity, and (3) plate-type instead of comb-type out-of-plane sensing electrodes are available to increase the sensing electrode area. To demonstrate the feasibility of the present design, a three-axis capacitive CMOS-MEMS accelerometers chip is implemented and characterized. Measurements show that the sensitivities of accelerometers reach 11.5 mV G-1 (in the X-, Y-axes) and 7.8 mV G-1 (in the Z-axis), respectively, which are nearly one order larger than existing designs. Moreover, the detection of 10 mG excitation using the three-axis accelerometer is demonstrated for both in-plane and out-of-plane directions.

  10. Evaluation of Tazobactam-Supplemented, Modified Charcoal-Cefoperazone-Deoxycholate Agar for Qualitative Detection of Campylobacter from Chicken Carcass Rinse.

    PubMed

    Chon, Jung-Whan; Kim, Young-Ji; Kim, Hong-Seok; Kim, Dong-Hyeon; Jeong, Dong Kwan; Seo, Kun-Ho

    2016-05-01

    Overgrowth of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli on modified charcoal-cefoperazone-deoxycholate agar (mCCDA) is the most common confounding factor for the isolation of Campylobacter from poultry samples. mCCDA modified by supplementation with tazobactam, an ESBL inhibitor, was evaluated for Campylobacter isolation from chicken carcass rinse with regard to isolation rate and selectivity. In total, 120 whole chicken carcasses purchased from retail stores were rinsed with buffered peptone water enriched with 2× blood-free Bolton broth at 42°C for 48 h and then inoculated onto mCCDA with and without tazobactam supplementation (mCCDA or T-mCCDA) at 42°C for 48 h under microaerobic conditions. Suspect colonies were subcultured and confirmed by colony PCR. Plates with tazobactam exhibited a higher Campylobacter isolation rate (56.7% vs. 30.8%, p < 0.05) and selectivity (0.8 vs. 83.3% plates contaminated with non-Campylobacter, p < 0.05) than mCCDA. Thus, tazobactam-supplemented mCCDA would be a useful option for qualitative detection of Campylobacter in chicken carcass rinse. PMID:27043031

  11. Fractionation of nuclei from brain by zonal centrifugation and a study of the ribonucleic acid polymerase activity in the various classes of nuclei

    PubMed Central

    Austoker, J.; Cox, D.; Mathias, A. P.

    1972-01-01

    extent of formation of the four homopolymers roughly parallels the RNA polymerase activity. ImagesFig. 1.PLATE 1PLATE 2 PMID:4348169

  12. Novel Simplified and Rapid Method for Screening and Isolation of Polyunsaturated Fatty Acids Producing Marine Bacteria

    PubMed Central

    Tilay, Ashwini; Annapure, Uday

    2012-01-01

    Bacterial production of polyunsaturated fatty acids (PUFAs) is a potential biotechnological approach for production of valuable nutraceuticals. Reliable method for screening of number of strains within short period of time is great need. Here, we report a novel simplified method for screening and isolation of PUFA-producing bacteria by direct visualization using the H2O2-plate assay. The oxidative stability of PUFAs in growing bacteria towards added H2O2 is a distinguishing characteristic between the PUFAs producers (no zone of inhibition) and non-PUFAs producers (zone of inhibition) by direct visualization. The confirmation of assay results was performed by injecting fatty acid methyl esters (FAMEs) produced by selected marine bacteria to Gas Chromatography-Mass Spectrometry (GCMS). To date, this assay is the most effective, inexpensive, and specific method for bacteria producing PUFAs and shows drastically reduction in the number of samples thus saves the time, effort, and cost of screening and isolating strains of bacterial PUFAs producers. PMID:22934188

  13. Highly ordered surface structure of large-scale porphyrin aggregates assembled from protonated TPP and water

    NASA Astrophysics Data System (ADS)

    Udal'tsov, Alexander V.; Bolshakova, Anastasia V.; Vos, Johannes G.

    2014-05-01

    Large-scale aggregates assembled from protonated meso-tetraphenylporphine (TPP) dimers and water have been investigated by IR and resonance Raman spectroscopy and also by scanning electron microscopy (SEM). It was found that the properties of water confined in the aggregates depend on the physical state of the support. When the aggregates were deposited on a solid CaF2 plate, they showed properties consistent with a quasi-crystalline structure. But when the aggregates were dispersed in oil, their IR characteristics were different; the vibration bands of the confined water were like those of water in liquid state. A doublet at about 1000 cm-1, components of which have been attributed to specific vibrations of H3O+ and H2O bound in the structure of water-porphyrin dimeric complex, was found in IR and resonance Raman spectra (λex = 441.6 nm) of protonated TPP aggregates. This doublet indicates the hydrogen ion involving in the vibrational system of water-porphyrin dimeric complex with hydrogen bonding by similar way as in so-called Zundel cation. The resonance Raman spectrum shows evidence for proton sharing between protonated water dimer and N groups of the pyrrole rings. SEM results indicate that the large-scale aggregates of the protonated porphyrin possess highly ordered structure, are only observed when using extremely pure water.

  14. Biomechanical evaluation of malleable noncompression miniplates in mandibular angle fractures: an experimental study.

    PubMed

    Esen, Alparslan; Dolanmaz, Doğan; Tüz, Hakan Hıfzı

    2012-07-01

    The purpose of this experimental study was to test the reliability of a single malleable titanium miniplate using Champy's method of fixing fractures of the mandibular angle. Eighteen sheep hemimandibles were used to evaluate 2 plating techniques. The groups were tested with either a single non-compression titanium miniplate or a single malleable titanium miniplate. A cantilever bending biomechanical test model was used for the samples. Each group was tested with vertical forces using a servohydraulic testing unit. The displacement values in each group at each 10N stage up to 90N were compared using 2-way analysis of variance (ANOVA). The displacement values for the 2 groups differed significantly (p<0.01). The variance analyses showed that the biomechanical behaviour of a single non-compression miniplate was better than that of a single malleable miniplate. The non-compression miniplate fixed by screws had greater resistance to occlusal loads than the malleable plate fixed by screws, and the malleable plate alone was not sufficient to withstand the early postoperative bite force. PMID:22118919

  15. Q-plates as higher order polarization controllers for orbital angular momentum modes of fiber.

    PubMed

    Gregg, P; Mirhosseini, M; Rubano, A; Marrucci, L; Karimi, E; Boyd, R W; Ramachandran, S

    2015-04-15

    We demonstrate that a |q|=1/2 plate, in conjunction with appropriate polarization optics, can selectively and switchably excite all linear combinations of the first radial mode order |l|=1 orbital angular momentum (OAM) fiber modes. This enables full mapping of free-space polarization states onto fiber vector modes, including the radially (TM) and azimuthally polarized (TE) modes. The setup requires few optical components and can yield mode purities as high as ∼30  dB. Additionally, just as a conventional fiber polarization controller creates arbitrary elliptical polarization states to counteract fiber birefringence and yield desired polarizations at the output of a single-mode fiber, q-plates disentangle degenerate state mixing effects between fiber OAM states to yield pure states, even after long-length fiber propagation. We thus demonstrate the ability to switch dynamically, potentially at ∼GHz rates, between OAM modes, or create desired linear combinations of them. We envision applications in fiber-based lasers employing vector or OAM mode outputs, as well as communications networking schemes exploiting spatial modes for higher dimensional encoding. PMID:25872059

  16. The StarScan Plate Measuring Machine: Overview and Calibrations

    NASA Astrophysics Data System (ADS)

    Zacharias, N.; Winter, L.; Holdenried, E. R.; De Cuyper, J.-P.; Rafferty, T. J.; Wycoff, G. L.

    2008-06-01

    The StarScan machine at the U.S. Naval Observatory (USNO) completed measuring photographic astrograph plates to allow determination of proper motions for the USNO CCD Astrograph Catalog (UCAC) program. All applicable 1940 AGK2 plates, about 2200 Hamburg Zone Astrograph plates, 900 Black Birch (USNO Twin Astrograph) plates, and 300 Lick Astrograph plates have been measured. StarScan comprises a CCD camera, a telecentric lens, an air-bearing granite table, stepper motor screws, and Heidenhain scales to operate in a step-stare mode. The repeatability of StarScan measures is about 0.2 μm. The CCD mapping as well as the global table coordinate system has been calibrated using a special dot calibration plate and the overall accuracy of StarScan x, y data is derived to be 0.5 μm. Application to real photographic plate data shows that position information of at least 0.65 μm accuracy can be extracted from coarse-grain 103a-type emulsion astrometric plates. Transformations between "direct" and "reverse" measures of fine-grain emulsion plate measures are obtained on the 0.3 μm level per well-exposed stellar image and coordinate, a level that is at the limit of the StarScan machine.

  17. Isolation and characterization of rabbit kidney brush borders

    PubMed Central

    Quirk, S. J.; Robinson, G. B.

    1972-01-01

    1. Brush borders were isolated from rabbit kidney-cortex homogenates by rate-zonal centrifugation through a sucrose density gradient in a B-XIV zonal rotor, followed by differential centrifugation. 2. The method of preparation gave brush borders of high purity with a reasonable yield. The morphological appearance supported the evidence from enzymic and chemical investigations, that the brush borders were only slightly contaminated with endoplasmic reticulum, mitochondria, lysosomes and nuclei. 3. The molar ratio of cholesterol to phospholipid lay within the range found in other plasma membranes, but the carbohydrate content was double that found in liver plasma membranes. 4. Alkaline phosphatase, maltase, trehalase and aminopeptidase were major enzymic constituents of the brush borders, and had an approximately equal yield and enrichment, but none of these enzymes fulfilled the criteria for marker enzymes. 5. Mg2+-dependent and Na+,K+-dependent adenosine triphosphatases, although found in brush borders, had low yields and low enrichments. ImagesPLATE 2PLATE 1 PMID:4264701

  18. Vacuum thermal switch made of phase transition materials considering thin film and substrate effects

    NASA Astrophysics Data System (ADS)

    Yang, Yue; Basu, Soumyadipta; Wang, Liping

    2015-06-01

    In the present study, we theoretically demonstrate a vacuum thermal switch based on near-field thermal radiation between phase transition materials, i.e., vanadium dioxide (VO2), whose phase changes from insulator to metal at 341 K. Strong coupling of surface phonon polaritons between two insulating VO2 plates significantly enhances the near-field heat flux, which on the other hand is greatly reduced when the VO2 emitter becomes metallic, resulting in strong thermal switching effect. Fluctuational electrodynamics incorporated with anisotropic wave propagation predicts more than 80% heat transfer reduction at sub-30-nm vacuum gaps and 50% at vacuum gap of 1 μm. Furthermore, the penetration depth inside the uniaxial VO2 insulator is studied at the vacuum gap of 50 nm, suggesting the possible impact of reduced VO2 thickness on the near-field thermal radiation with thin-film structures. By replacing the bulk VO2 receiver with a thin film of several tens of nanometers, the switching effect is further improved over a broad range of vacuum gaps from 10 nm to 1 μm. Finally, the effect of SiO2 substrate for the thin-film emitter or receiver is also considered to provide insights for future experimental demonstrations. By controlling heat flow with near-field radiative transport, the proposed vacuum thermal switch would find practical applications for energy dissipation in microelectronic devices and for the realization of thermal circuits.

  19. Laser-frequency multiplication

    SciTech Connect

    Not Available

    1991-11-01

    A high quality mode locked pulse train was obtained at 9.55 micrometers, the CO2 wavelength chosen for frequency doubling into the atmospheric window at 4.8 micrometers. The pulse train consists of a 3 micro sec burst of 1.5 nsec pulses separated by 40 nsec, in a TEM(00) mode and with a total energy of 100 mJ. The pulse intensity without focussing is about 3 MW/sq.cm., already quite close to the target intensity of 10 MW/sq.cm. for frequency doubling in a AgGaSe2 crystal. The mode-locked train is obtained by intracavity modulation at 12.5 MHz using a germanium crystal driven with a power of about 30 Watts. Line selection is achieved firstly by the use of a 0.92 mm thick CaF2 plate at the Brewster angle within the cavity, which completely suppresses 10.6 micrometer band radiation. Secondly, a particular rotational line, the P20 at 9.55 micrometers, is selected by the injection of a continuous beam is mode-matched to the pulsed laser cavity using a long focal length lens, and for best line-locking it is necessary to fine tune the length of the pulsed laser resonator. Injection causes substantial depression of the gain switched spike.

  20. Changes in the soil microbial community with a pine plantation restoration in a dry valley of the upper reaches of the Minjiang River, southwest China.

    PubMed

    Liu, Zhanfeng; Liu, Guohua; Fu, Bojie; Wu, Yaqiong; Hu, Huifeng; Fu, Shenglei

    2010-05-01

    The objective of this study was to investigate the changes in soil microbial biomass C, microbial metabolic activity, functional diversity, and metabolic diversity pattern during the restoration process of a pine (Pinus tabulaeformis) plantation. In this study, a chronosequence approach was adopted. Three sites of pine plantations along a restoration chronosequence (12 years old (PF12), 25 years old (PF25), 35 years old (PF35)), and their paired reference sites of natural shrub community (Shrub1, Shrub2, and Shrub3) were selected. Soil microbial biomass C increased and microbial quotient declined with pine plantation age. Microbial metabolic activity, as measured by average well color development (using Biolog GN(2) plates), exhibited a decline along the restoration chronosequence with values ranked as PF12 > PF35 > PF25 in topsoil and PF12 > PF25 > PF35 in subsoil. Functional diversity, as estimated by substrate diversity and substrate richness, exhibited a pattern similar to the metabolic activity. Principal component analysis indicated that metabolic diversity followed recognized patterns along the restoration chronosequence with PF12 significantly different from PF25 and PF35. There was an apparent reduction of microbial metabolic activity and functional diversity during pine plantation restoration, which can be explained by a general decline in soil nutrient availability, particularly C availability, and soil pH associated with the establishment of a coniferous species. PMID:20586776

  1. Sensory physiology, anatomy and immunohistochemistry of Rohon-Beard neurones in embryos of Xenopus laevis.

    PubMed Central

    Clarke, J D; Hayes, B P; Hunt, S P; Roberts, A

    1984-01-01

    Rohon-Beard neurones show substance P-like immunoactivity in their somas and in their centrally projecting axons. Peripherally, the morphology of their free nerve endings within the trunk skin has been shown using horseradish peroxidase staining. The excitation of Rohon-Beard neurones by natural and electrical stimulation of the skin has been examined using intracellular micro-electrodes in the late embryo of Xenopus laevis. Rohon-Beard cells are sensitive to transient, local indentation of the trunk skin, responding with one or a few impulses. They adapt rapidly to repeated stimulation. They can also be excited by a brief current pulse to the skin. They are not sensitive to slow indentation of the skin, nor are they excited by epithelial action potentials. The responses to skin stimulation are not abolished by a Ringer solution containing 12 mM-Mg2+ and only 0.5 mM-Ca2+. Intracellularly evoked action potentials in single Rohon-Beard cells are sometimes sufficient to evoke sustained episodes of fictive swimming. The results indicate that Rohon-Beard cells are responsible for detecting light touch stimuli to the embryo's body and for initiating swimming in response to this stimulus. Images PLATE 2 PLATE 1 PMID:6201612

  2. Investigation of the solar influence on the cosmic muon flux using WILLI detector

    NASA Astrophysics Data System (ADS)

    Saftoiu, A.; Bercuci, A.; Brancus, I. M.; Duma, M.; Haungs, A.; Mitrica, B.; Petcu, M.; Rebel, H.; Sima, O.; Toma, G.

    2010-11-01

    A fesibility study to explore the capability of the WILLI detector to observe the solar events/activity by recording the muon intensity at ground level is presented. The WILLI detector, set up in National Institute of Physics and Nuclear Engineering, Bucharest, is a 1 m2 incident area sampling calorimeter. It can measure simultaneously muon events with the muon energy >=0.4 GeV and, if the muons are stopped in the detector, and muon energy between 0.42 plates of the detector stack. Taking into account muon events with energy >=0.4 GeV, a modulation of the muon intensity as a diurnal variation is observed. Muon events for a smaller energy range (0.4-0.6 GeV) seem to exhibit an aperiodic variation of the muon intensity, which could be correlated with magnetic activity indicated by the planetary Kp index.

  3. Performance assessment of CsI(Tl) screens on various substrates for X-ray imaging

    NASA Astrophysics Data System (ADS)

    Feng, Zhao-Dong; Jiang, Peng; Zhang, Hong-Kai; Zhao, Bo-Zhen; Qin, Xiu-Bo; Wei, Cun-Feng; Liu, Yu; Wei, Long

    2015-07-01

    Thallium-doped cesium iodide (CsI(Tl)) screens are widely used in X-ray imaging devices because of the columnar structure of the CsI(Tl) layer, but few reports focus on the optical role of the substrate in the screen system. In this paper, four substrates including fused silica (SiO2), silver-film coated SiO2, graphite (C) and fiber optic plate (FOP) are used to fabricate CsI(Tl) screens by thermal evaporation. Their imaging performance is evaluated by relative light output (RLO), modulation transfer function (MTF), normalized noise power spectrum (NNPS) and noise equivalent quanta (NEQ). The results reveal that although CsI(Tl) film on graphite plate yields images with the lowest light output, it presents relatively higher spatial resolution and better signal-to-noise characteristics. However, films on SiO2 plate obtain low MTF but high NNPS curves, whether they are coated with silver film or not. Furthermore, scintillation screens on FOP have bright images with low NNPS and high NEQ, but have the lowest MTF. By controlling the substrate optical features, CsI(Tl) films can be tailored to suit a given application. Supported by National Key Scientific Instrument and Equipment Development Project (2011YQ03011205, 2013YQ03062902) and Key Program of the National Natural Science Foundation of China (U1332202)

  4. Preparation of α-SnWO4/SnO2 heterostructure with enhanced visible-light-driven photocatalytic activity

    NASA Astrophysics Data System (ADS)

    Yao, Shiyue; Zhang, Min; Di, Junwei; Wang, Zuoshan; Long, Yumei; Li, Weifeng

    2015-12-01

    In this work, a novel α-SnWO4/SnO2 heterostructure was synthesized via a facile two-step hydrothermal method. The as-prepared products were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scan electron microscopy (SEM) and transmission electron microscopy (TEM), which confirmed the typical orthorhombic α-SnWO4 phase, plate-like morphology and α-SnWO4/SnO2 heterostructure. The photocatalytic studies revealed that the attachment of SnO2 nanoparticles on the surface of α-SnWO4 plates can remarkably improve their photocatalytic activities and the α-SnWO4/SnO2 heterostructure exhibited the best photocatalytic properties in the degradation of methyl orange (MO) under visible light irradiation. The degradation rate of MO on α-SnWO4/SnO2 plate was 97% within 40 min and the photocatalytic degradation reaction followed the pseudo-first-order kinetics. The enhanced photocatalytic property was ascribed to the large surface area and the heterojuction between α-SnWO4 and SnO2, which can facilitate efficient charge separation of photogenerated electron-hole pairs. Furthermore, α-SnWO4/SnO2 nanocomposite demonstrated good recyclability, which is useful for its practical application.

  5. Highly Efficient and Robust Nickel Phosphides as Bifunctional Electrocatalysts for Overall Water-Splitting.

    PubMed

    Li, Jiayuan; Li, Jing; Zhou, Xuemei; Xia, Zhaoming; Gao, Wei; Ma, Yuanyuan; Qu, Yongquan

    2016-05-01

    To search for the efficient non-noble metal based and/or earth-abundant electrocatalysts for overall water-splitting is critical to promote the clean-energy technologies for hydrogen economy. Herein, we report nickel phosphide (NixPy) catalysts with the controllable phases as the efficient bifunctional catalysts for water electrolysis. The phases of NixPy were determined by the temperatures of the solid-phase reaction between the ultrathin Ni(OH)2 plates and NaH2PO2·H2O. The NixPy with the richest Ni5P4 phase synthesized at 325 °C (NixPy-325) delivered efficient and robust catalytic performance for hydrogen evolution reaction (HER) in the electrolytes with a wide pH range. The NixPy-325 catalysts also exhibited a remarkable performance for oxygen evolution reaction (OER) in a strong alkaline electrolyte (1.0 M KOH) due to the formation of surface NiOOH species. Furthermore, the bifunctional NixPy-325 catalysts enabled a highly performed overall water-splitting with ∼100% Faradaic efficiency in 1.0 M KOH electrolyte, in which a low applied external potential of 1.57 V led to a stabilized catalytic current density of 10 mA/cm(2) over 60 h. PMID:27064172

  6. Fabrication and performance studies of a cable-type flexible asymmetric supercapacitor.

    PubMed

    Senthilkumar, S T; Kalai Selvan, R

    2014-08-01

    In the present work a novel cable-type asymmetric supercapacitor was fabricated using plate-like β-Ni(OH)2 as the positive and activated carbon as the negative electrode, with polyvinyl alcohol-KOH (PVA-KOH) as the gel polymer electrolyte. The β-Ni(OH)2 plates were prepared by a reflux method and the activated carbon was derived from Tamarindus indica fruit shell by chemical activation. The working voltage of the fabricated cable-type asymmetric supercapacitor (ASC) was 1.4 V, and it achieved per-unit-length and gravimetric capacitances of 40.7 mF cm(-1) and 37.5 F g(-1) respectively at 2 mA. Besides, the fabricated ASC delivered a maximum per-unit-length (gravimetric) energy density of 10.7 μW h cm(-1) (9.8 W h kg(-1)) at a power density of 169 μW cm(-1) (154 W kg(-1)). In addition, it exhibited a better capacitance retention, of 88% over 1000 cylces and 76% over 2000 cycles. PMID:24960123

  7. The organ-specificity of ferritin in human and horse liver and spleen

    PubMed Central

    Crichton, R. R.; Millar, J. A.; Cumming, R. L. C.; Bryce, C. F. A.

    1973-01-01

    1. Ferritin was isolated from human and horse spleen and liver, and apoferritin prepared therefrom. 2. The electrophoretic mobilities of the four apoferritins were determined on polyacrylamide gels and on cellulose acetate strips, and all found to be equal. 3. Homologous ferritins share reactions of identity in immunodiffusion experiments, whereas heterologous ferritins show only partial identity. 4. The subunit molecular weight of each of the apoferritins was determined by polyacrylamide-gel electrophoresis in sodium dodecyl sulphate and by chromatography on agarose columns in 6m-guanidine–HCl. A value of approx. 18500 was found in all cases. The proteins all had sedimentation coefficients of 17–18S. It thus seems that they have identical quaternary structures. 5. The amino acid compositions of the proteins revealed distinct differences both between organs and between species. This was confirmed by analysis of the tryptic peptide patterns, where it was found that about one-third of the peptides were common to the four proteins and the other two-thirds varied from protein to protein. 6. It is concluded that the apoferritins present in the liver and spleen of human and horse are both organ- and species-specific. 7. The apoferritin isolated from the liver of a patient with idiopathic haemochromatosis was identical with normal human liver apoferritin by the criteria described above. ImagesPLATE 2PLATE 1(a)PLATE 1(b) PMID:4198584

  8. Thin-layer chromatography and mass spectrometry coupled using desorption electrospray ionization.

    PubMed

    Van Berkel, Gary J; Ford, Michael J; Deibel, Michael A

    2005-03-01

    Desorption electrospray ionization (DESI) was demonstrated as a means to couple thin-layer chromatography (TLC) with mass spectrometry. The experimental setup and its optimization are described. Development lanes were scanned by moving the TLC plate under computer control while directing the stationary DESI emitter charged droplet plume at the TLC plate surface. Mass spectral data were recorded in either selected reaction monitoring mode or in full scan ion trap mode using a hybrid triple quadrupole linear ion trap mass spectrometer. Fundamentals and practical applications of the technique were demonstrated in positive ion mode using selected reaction monitoring detection of rhodamine dyes separated on hydrophobic reversed-phase C8 plates and reversed-phase C2 plates, in negative ion full scan mode using a selection of FD&C dyes separated on a wettable reversed-phase C18 plate, and in positive ion full scan mode using a mixture of aspirin, acetaminophen, and caffeine from an over-the-counter pain medication separated on a normal-phase silica gel plate. PMID:15732898

  9. Asymmetric polarization-based frequency shifting interferometer for microelectronics

    NASA Astrophysics Data System (ADS)

    Lee, Seung Hyun; Kim, Min Young

    2014-05-01

    Frequency Scanning Interferometry(FSI) generally results in superior optical performance comparing with other 3-dimensional measuring methods as its hardware structure is fixed in operation and only the light frequency is scanned in a specific spectral band without vertical scanning of the target surface or the objective lens. However, it still suffers from optical noise due to polarization characteristic of target surfaces and relatively long processing time due to the number of images acquired in frequency scanning phase. First, a Polarization-based Frequency Scanning Interferometry(PFSI) is proposed for optical noise robustness. It consists of tunable laser for light source, λ/4 plate in front of reference mirror, λ /4 plate in front of target object, polarizing beam splitter, polarizer in front of image sensor, polarizer in front of the fiber coupled light source, λ/2 plate between PBS and polarizer of the light source. Using the proposed system, we can solve the problem of fringe image with low contrast by using polarization technique. Also, we can control light distribution of object beam and reference beam. Second the signal processing acceleration method is proposed for PFSI, based on parallel processing architecture, which consists of parallel processing hardware and software such as Graphic Processing Unit(GPU) and Compute Unified Device Architecture(CUDA). Finally, the proposed system is evaluated in terms of accuracy and processing speed through a series of experiment and the obtained results show the effectiveness of the proposed system and method.

  10. Crustal structure of Precambrian terranes in the southern African subcontinent with implications for secular variation in crustal genesis

    NASA Astrophysics Data System (ADS)

    Kachingwe, Marsella; Nyblade, Andrew; Julià, Jordi

    2015-07-01

    New estimates of crustal thickness, Poisson's ratio and crustal shear wave velocity have been obtained for 39 stations in Angola, Botswana, the Democratic Republic of Congo, Malawi, Mozambique, Namibia, Rwanda, Tanzania and Zambia by modelling P-wave receiver functions using the H-κ stacking method and jointly inverting the receiver functions with Rayleigh-wave phase and group velocities. These estimates, combined with similar results from previous studies, have been examined for secular trends in Precambrian crustal structure within the southern African subcontinent. In both Archean and Proterozoic terranes we find similar Moho depths [38-39 ± 3 km SD (standard deviation)], crustal Poisson's ratio (0.26 ± 0.01 SD), mean crustal shear wave velocity (3.7 ± 0.1 km s-1 SD), and amounts of heterogeneity in the thickness of the mafic lower crust, as defined by shear wave velocities ≥4.0 km s-1. In addition, the amount of variability in these crustal parameters is similar within each individual age grouping as between age groupings. Thus, the results provide little evidence for secular variation in Precambrian crustal structure, including between Meso- and Neoarchean crust. This finding suggests that (1) continental crustal has been generated by similar processes since the Mesoarchean or (2) plate tectonic processes have reworked and modified the crust through time, erasing variations in structure resulting from crustal genesis.

  11. Effect of succinylation (3-carboxypropionylation) on the conformation and immunological activity of ovalbumin.

    PubMed Central

    Kidwai, S A; Ansari, A A; Salahuddin, A

    1976-01-01

    The epsilon-amino groups of ovalbumin were modified with succinic anhydride; as many as 16 lysine residues were succinylated (3-carboxypropionylated). The five succinylated derivatives thus prepared were homogeneous with respect to the extent of chemical modification as shown by electrophoretic and immunological data. Succinylation of the amino groups altered electrophoretic mobility and isoionic pH of ovalbumin in the expected direction. U.v.-absorption and fluorescence spectra suggested changes in the microenvironment of the chromophores in the modified proteins. The difference-spectral results showed greater exposure of tyrosine and tryptophan residues in the succinylated ovalbumin. Increase in susceptibility to tryptic digestion, Stokes radius and intrinsic viscosity of native ovalbumin, which was observed on successive increase in the chemical modification, demonstrated a conformational change that was proportional to the extent of modification. The loss of immunological reactivity caused by chemical modification also indicated a conformational change in succinylated ovalbumin. The fact that the intrinsic viscosity of maximally modified ovalbumin was less than one-third of that for the completely denatured protein in 6M-guanidinium chloride suggested that the modified protein contained significant residual native structure. The latter presumably accommodates some antigenic determinants accounting for 37% residual immunological activity observed with maximally succinylated ovalbumin. Images PLATE 2 PLATE 1 PMID:820333

  12. Development of technology for modeling of a 1/8-scale dynamic model of the shuttle Solid Rocket Booster (SRB)

    NASA Technical Reports Server (NTRS)

    Levy, A.; Zalesak, J.; Bernstein, M.; Mason, P. W.

    1974-01-01

    A NASTRAN analysis of the solid rocket booster (SRB) substructure of the space shuttle 1/8-scale structural dynamics model. The NASTRAN finite element modeling capability was first used to formulate a model of a cylinder 10 in. radius by a 200 in. length to investigate the accuracy and adequacy of the proposed grid point spacing. Results were compared with a shell analysis and demonstrated relatively accurate results for NASTRAN for the lower modes, which were of primary interest. A finite element model of the full SRB was then formed using CQUAD2 plate elements containing membrane and bending stiffness and CBAR offset bar elements to represent the longerons and frames. Three layers of three-dimensional CHEXAI elements were used to model the propellant. This model, consisting of 4000 degrees of freedom (DOF) initially, was reduced to 176 DOF using Guyan reduction. The model was then submitted for complex Eigenvalue analysis. After experiencing considerable difficulty with attempts to run the complete model, it was split into two substructres. These were run separately and combined into a single 116 degree of freedom A set which was successfully run. Results are reported.

  13. Bounding criticality safety analyses for shipments of unconfigured spent nuclear fuel

    SciTech Connect

    Lichtenwalter, J.J.; Parks, C.V.

    1998-06-01

    In November 1996, a request was made to the US Department of Energy for a waiver for three shipments of spent nuclear fuel (SNF) from Oak Ridge National Laboratory (ORNL) to the Savannah River Site (SRS) in the US NRC certified BMI-1 cask (CoC 5957). Although the post-irradiation fissile mass (based on chemical assays) in each shipment was less than 800 g, a criticality safety analysis was needed because the pre-irradiation mass exceeded 800 g, the fissile material limit in the CoC. The analyses were performed on SNF consisting of aluminum-clad U{sub 3}O{sub 8}, UAl{sub x}, and U{sub 3}Si{sub 2} plates, fragments and pieces that had been irradiated at ORNL during the Reduced Enrichment Research and Test Reactor Program of the 1980s. The highlights of the approach used to analyze this unique SNF and the benefits of the waiver are presented in this paper.

  14. A simple and inclusive method to determine the habit plane in transmission electron microscope based on accurate measurement of foil thickness

    SciTech Connect

    Qiu, Dong Zhang, Mingxing

    2014-08-15

    A simple and inclusive method is proposed for accurate determination of the habit plane between bicrystals in transmission electron microscope. Whilst this method can be regarded as a variant of surface trace analysis, the major innovation lies in the improved accuracy and efficiency of foil thickness measurement, which involves a simple tilt of the thin foil about a permanent tilting axis of the specimen holder, rather than cumbersome tilt about the surface trace of the habit plane. Experimental study has been done to validate this proposed method in determining the habit plane between lamellar α{sub 2} plates and γ matrix in a Ti–Al–Nb alloy. Both high accuracy (± 1°) and high precision (± 1°) have been achieved by using the new method. The source of the experimental errors as well as the applicability of this method is discussed. Some tips to minimise the experimental errors are also suggested. - Highlights: • An improved algorithm is formulated to measure the foil thickness. • Habit plane can be determined with a single tilt holder based on the new algorithm. • Better accuracy and precision within ± 1° are achievable using the proposed method. • The data for multi-facet determination can be collected simultaneously.

  15. Photoelasticy method for study of structural imperfection of ZnGeP2 crystals

    NASA Astrophysics Data System (ADS)

    Lei, Zuotao; Okunev, A. O.; Zhu, Chongqiang; Verozubova, G. A.; Ma, Tianhui; Yang, Chunhui

    2016-09-01

    The stresses, related to rows and accumulations of dislocations were revealed by photoelastic method for ZnGeP2 crystals, grown by Vertical Bridgman method. A comparison of information from topographs of photoelastic method and X-Ray topography based on Borrmann method was carried out. It was shown that the strongest contrast is observed on boundaries of dislocation rows and regions of relatively perfect crystals. Photoelastic method gives information about defect structure, where X-Ray topography can not be applied because of high density of defects and disorientation of reflection planes. Because of high sensitivity of photoelastic method the images of defects have larger size then in X-Ray topography. That is why in ZnGeP2 predominately the total contrast from dislocation rows is fixed. However, in low angle boundaries photoelastic images of separate dislocations were revealed. By comparison with results of simulation it was stated that they are created by edge dislocation of slip system { 1 bar 10 } < 110 > , what confirms the data, obtained by Borrmann method. Thus, photoelastic method can be from one side a simple and express method of analysis of ZnGeP2 plates cut along the plane of optical isotropy (001), and from other side an analytical method of identification of dislocations and other defects in this material.

  16. MTR plates modeling with MAIA

    SciTech Connect

    Marelle, V.; Dubois, S.; Ripert, M.; Noirot, J.

    2008-07-15

    MAIA is a thermo-mechanical code dedicated to the modeling of MTR fuel plates. The main physical phenomena modeled in the code are the cladding oxidation, the interaction between fuel and Al-matrix, the swelling due to fission products and the Al/fuel particles interaction. The creeping of the plate can be modeled in the mechanical calculation. MAIA has been validated on U-Mo dispersion fuel experiments such as IRIS 1 and 2 and FUTURE. The results are in rather good agreement with post-irradiation examinations. MAIA can also be used to calculate in-pile behavior of U{sub 3}Si{sub 2} plates as in the SHARE experiment irradiated in the SCK/Mol BR2 reactor. The main outputs given by MAIA throughout the irradiation are temperatures, cladding oxidation thickness, interaction thickness, volume fraction of meat constituents, swelling, displacements, strains and stresses. MAIA is originally a two-dimensional code but a three-dimensional version is currently under development. (author)

  17. Wakefield Excitation by a Sequence of Electron Bunches in a Rectangular Waveguide Lined with Dielectric Slabs

    SciTech Connect

    Kiselev, V. A.; Linnik, A. F.; Onishchenko, I. N.; Onishchenko, N. I.; Sotnikov, G. V.; Uskov, V. V.; Marshall, T. C.

    2006-11-27

    A rectangular dielectric-lined metallic structure was studied that has an advantage over a cylindrical structure from the possibility of exciting by a sequence of bunches many equally-spaced modes, thereby building up a larger mode-locked wakefield. A rectangular vacuum copper waveguide was lined with two dielectric slabs, the size of which was calculated to provide resonant excitation of the fundamental LSM mode by a sequence of bunches with repetition frequency f0=2805 MHz, produced by linear resonant electron accelerator (4.5 MeV, number of bunches 6.103, diameter 1cm, duration 60 ps each, distance between bunches 300 ps, number of electrons in each bunch 109). The waveguide has cross section 85 mm x 180 mm, and Teflon ({epsilon} 2.1) plates were placed along the smaller sides of the waveguide, their thickness from the calculation being 22 mm. In experiments, the length of the resonator was 535mm. We found that the total wakefield is three times larger than the fundamental mode; thus a greater number of excited modes was excited compared with the cylindrical case, for which this ratio was only 1.5. We found considerably more energy loss of electron bunches for the resonator case compared with the waveguide case.

  18. Management of pediatric mandibular fractures using bioresorbable plating system – Efficacy, stability, and clinical outcomes: Our experiences and literature review

    PubMed Central

    Singh, Mahinder; Singh, R.K.; Passi, Deepak; Aggarwal, Mohit; Kaur, Guneet

    2015-01-01

    Aims The purpose of this study was to determine the efficacy and stability of the biodegradable fixation system for treatment of mandible fractures in pediatric patients by measuring the bite force. Methods Sixty pediatric patients with mandibular fractures (36 males, 24 females) were included in this study. The 2.5-mm resorbable plates were adapted along Champy's line of ideal osteosynthesis and secured with four 2.5 mm diameter monocortical resorbable screws, 8 mm in length. All patients were followed for 10 months. Clinical parameters, such as soft tissue infection, nonunion, malunion, implant exposure, malocclusion, nerve injury, and bite force for stability, were prospectively assessed. Results Adequate fixation and primary bone healing was achieved in 100% of the cases. Six minor complications (10%) were observed: 2 soft tissue infections (3%), 1 plate dehiscence (2%), 1 malocclusion (2%), and 2 paresthesia (3%). Conclusion 2.5-mm resorbable plating system along Champy's line of ideal osteosynthesis is a good treatment modality for mandible fractures in pediatric patients. PMID:27195206

  19. Sensory deprivation during development decreases the responsiveness of cricket giant interneurones

    PubMed Central

    Matsumoto, S. G.; Murphey, R. K.

    1977-01-01

    1. The effect sensory deprivation, early in development, has on the adult response properties of identified neurones was studied in the abdominal nervous system of the cricket Acheta domesticus. 2. Neural activity in the cercal-to-giant interneurone system was lowered by blocking the movement of the mechanosensitive hairs, located on each cercus, with a facial cleansing cream. 3. When specimens were treated unilaterally one of a pair of homologous neurones exhibited drastically altered response properties. The neurone which received its afferent input from the treated receptors was much less sensitive to tones. Its threshold was increased approximately 20 db with respect to its untreated homologue. 4. Bilateral treatment lowered the responsiveness of both of the bilaterally homologous neurones. 5. Increased levels of inhibition impinging on the treated neurones accounts for part of the altered responsiveness. The inhibitory pathway is activated by the untreated mechanoreceptors. 6. Control experiments demonstrate that the sensory apparatus is not injured or modified by the treatment. 7. The results suggest that normal development of some invertebrate neural pathways may be more dependent on experience during ontogeny than has previously been assumed. ImagesPlate 1Plate 2 PMID:874920

  20. The release of nucleotides, 5-hydroxytryptamine and enzymes from human blood platelets during aggregation

    PubMed Central

    Mills, D. C. B.; Robb, I. A.; Roberts, G. C. K.

    1968-01-01

    1. Adenosine diphosphate (ADP) and adrenaline caused the aggregation of human platelets suspended in plasma containing citrate anticoagulant and stirred at 37° C. The aggregation occurred in two phases and the second phase was associated with the appearance in the plasma of up to 30% of the ATP and 55% of the ADP present in the platelets. The concentration of ADP appearing in the plasma was up to 7 times the concentration added. 2. Radioactivity was released by ADP and by adrenaline from platelets labelled with radioactive 5-hydroxytryptamine; this release was closely correlated with the second phase of aggregation and with the release of nucleotides. 3. Acid phosphatase, β-glucuronidase and adenylate kinase were released to a small extent during second phase aggregation by ADP or adrenaline; thrombin and collagen particles caused significantly greater release of β-glucuronidase than of either acid phosphatase or of adenylate kinase. 4. Morphological changes indicating degranulation of the platelets were observed during the second phase of aggregation produced by adrenaline and by ADP. 5. The second phase of aggregation, degranulation of platelets, and the release of nucleotides, of labelled 5-hydroxytryptamine and of enzymes, were all inhibited by concentrations of amitriptyline which did not inhibit aggregation. ImagesPlate 1Plate 2 PMID:5649642

  1. A global-local higher order theory including interlaminar stress continuity and C0 plate bending element for cross-ply laminated composite plates

    NASA Astrophysics Data System (ADS)

    Zhen, Wu; Wanji, Chen

    2010-04-01

    A C0-type global-local higher order theory including interlaminar stress continuity is proposed for the cross-ply laminated composite and sandwich plates in this paper, which is able to a priori satisfy the continuity conditions of transverse shear stresses at interfaces. Moreover, total number of unknowns involved in the model is independent of number of layers. Compared to other higher-order theories satisfying the continuity conditions of transverse shear stresses at interfaces, merit of the proposed model is that the first derivatives of transverse displacement w have been taken out from the in-plane displacement fields, so that the C0 interpolation functions is only required during its finite element implementation. To verify the present model, a C0 three-node triangular element is used for bending analysis of laminated composite and sandwich plates. It ought to be shown that all variables involved in present model are discretized by only using linear interpolation functions within an element. Numerical results show that the C0 plate element based on the present theory may accurately calculate transverse shear stresses without any postprocessing, and the present results agree well with those obtained from the C1-type higher order theory. Compared with the C1 plate bending element, the present finite element is simple, convenient to use and accurate enough.

  2. Recovery of slow and fast muscles following nerve injury during early post-natal development in the rat.

    PubMed Central

    Lowrie, M B; Krishnan, S; Vrbová, G

    1982-01-01

    1. The sciatic nerve was crushed in 5-6-day-old rats and the recovery of function of slow and fast muscles was studied. The first signs of recovery of function were seen 10-12 days after the operation. 2. Maximal tetanic tension developed by the reinnervated muscles was recorded and taken as an indication of their recovery. Two months after nerve crush, slow soleus muscles developed only slightly less tension than the control unoperated soleus muscles. The reinnervated fast muscles tibialis anterior (t.a.) and extensor digitorum longus (e.d.l.) developed only about 50% of the tension of the unoperated controls. 3. The fast muscles never recovered, remaining weaker and smaller throughout the animals' life. 4. The number of muscle fibres in the reinnervated fast muscles was substantially reduced and their fibre composition altered in that they contained mainly muscle fibres with high levels of oxidative enzymes. 5. The reinnervated fast muscles became much more fatigue resistant than the unoperated controls. 6. The possibility that these changes are due to motoneurone death was examined. The motoneurones innervating the fast muscles were labelled by retrograde transport of HRP. No significant reduction in the number of motoneurones innervating the operated muscles was found. 7. These results show that nerve injury during early post-natal life causes permanent changes in fast muscles that are not caused by motoneurone death. Images PLATE 1 (cont.) PLATE 1 PLATE 2 PMID:7153915

  3. Why subduction zones are curved

    NASA Astrophysics Data System (ADS)

    Mahadevan, L.; Bendick, R.; Liang, Haiyi

    2010-12-01

    We give an explanation for the polarity, localization, shape, size, and initiation of subduction zones on Earth. By considering a soft, thin, curved lithospheric cap with either elastic or viscous rheology supported by a thick, nearly incompressible mantle, we find two different characteristic subduction geometries arise depending on boundary conditions: (1) plate boundaries where subduction results primarily from the gravitational body force (free subduction) have characteristic plate lengths and form arc-shaped dimpled segments resulting from the competition between bending and stretching in edge buckling modes of thin spherical shells, and (2) subduction zones due to localized applied loads that push one slab of thin, positively buoyant lithosphere beneath an overriding plate (forced subduction) form localized straight segments, consistent with the deformation of indented spherical shells. Both types of subduction are nonlinear subcritical instabilities, so small perturbations in the mechanical properties of the lithosphere have pronounced effects on subduction initiation and evolution. Yet in both cases, geometric relationships determined by the shape of the Earth itself play the most critical role in controlling the basic morphology and characteristic length scales of subduction zones.

  4. The separation of β-glucanases produced by Cytophaga johnsonii and their role in the lysis of yeast cell walls

    PubMed Central

    Bacon, J. S. D.; Gordon, A. H.; Jones, D.; Tayor, Irene F.; Webley, D. M.

    1970-01-01

    1. When Cytophaga johnsonii was grown in the presence of suitable inducers the culture fluid was capable of lysing thiol-treated yeast cell walls in vitro. 2. Autoclaved or alkali-extracted cells, isolated cell walls and glucan preparations made from them were effective inducers, but living yeast cells or cells killed by minimal heat treatment were not. 3. Chromatographic fractionation of lytic culture fluids showed the presence of two types of endo-β-(1→3)-glucanase and several β-(1→6)-glucanases; the latter may be induced separately by growing the myxo-bacterium in the presence of lutean. 4. Extensive solubilization of yeast cell walls was obtained only with preparations of one of these glucanases, an endo-β-(1→3)-glucanase producing as end products mainly oligosaccharides having five or more residues. Lysis by the other endo-β-(1→3)-glucanase was incomplete. 5. The β-(1→6)-glucanases produced a uniform thinning of the cell walls, and mannan–peptide was found in the solution. 6. These results, and the actions of the enzyme preparations on a variety of wall-derived preparations made from baker's yeast, are discussed in the light of present conceptions of yeast cell-wall structure. ImagesPLATE 1PLATE 2 PMID:5494230

  5. PIV-based estimation of unsteady loads on a flat plate at high angle of attack using momentum equation approaches

    NASA Astrophysics Data System (ADS)

    Guissart, Amandine; Bernal, Luis; Dimitriadis, Gregorios; Terrapon, Vincent

    2015-11-01

    The direct measurement of loads with force balance can become challenging when the forces are small or when the body is moving. An alternative is the use of Particle Image Velocimetry (PIV) velocity fields to indirectly obtain the aerodynamic coefficients. This can be done by the use of control volume approaches which lead to the integration of velocities, and other fields deriving from them, on a contour surrounding the studied body and its supporting surface. This work exposes and discusses results obtained with two different methods: the direct use of the integral formulation of the Navier-Stokes equations and the so-called Noca's method. The latter is a reformulation of the integral Navier-Stokes equations in order to get rid of the pressure. Results obtained using the two methods are compared and the influence of different parameters is discussed. The methods are applied to PIV data obtained from water channel testing for the flow around a 16:1 plate. Two cases are considered: a static plate at high angle of attack and a large amplitude imposed pitching motion. Two-dimensional PIV velocity fields are used to compute the aerodynamic forces. Direct measurements of dynamic loads are also carried out in order to assess the quality of the indirectly calculated coefficients.

  6. Formation of bainite in ferrous and nonferrous alloys through sympathetic nucleation and ledgewise growth mechanism

    SciTech Connect

    Fang, H.S.; Wang, J.J.; Yang, Z.G.; Li, C.M.; Zheng, Y.K.; Li, C.X.

    1996-06-01

    The subunits constituting a bainitic sheaf in an Fe-C-Cr-Si alloy were discovered by scanning tunneling microscopy (STM) to consist of sub-subunits, and sub-subunits were also composed of sub-sub-subunits. Detailed investigation shows that a bainitic relief is composed of many smaller reliefs, which correspond to a different structure of bainite, i.e., subunits, sub-subunits, and sub-sub-subunits. It is determined by STM that the surface relief arising from the formation of bainite in an Fe-C-Cr alloy is tent shaped rather than an invariant plane strain (IPS) types of surface relief. Careful observation shows that the relief obtained from a sub-sub-subunit is also tent shaped. It is discovered by STM that an {alpha}{sub 1} plate, i.e., bainite formed in Cu-Zn-Al alloys, is composed of subunits. This is also demonstrated by transmission electron microscopy (TEM). The preceding results indicate that bainitic plates in Cu-Zn-Al alloys and bainitic subunits in steels are not the smallest structural units. Based on the preceding results on the ultrafine structure and the nature of surface relief accompanying bainite, it is proposed that the bainitic structure forms through a sympathetic nucleation and ledgewise growth (SNLG) mechanism. This article shows that the SNLG mechanism can be successfully applied to interpret the complicated structure of bainite.

  7. Formation of bainite in ferrous and nonferrous alloys through sympathetic nucleation and ledgewise growth mechanism

    NASA Astrophysics Data System (ADS)

    Fang, Hong-Sheng; Wang, Jia-Jun; Yang, Zhi-Gang; Li, C. M.; Zheng, Y. K.; Li, C. X.

    1996-06-01

    The subunits constituting a bainitic sheaf in an Fe-C-Cr-Si alloy were discovered by scanning tunneling microscopy (STM) to consist of sub-subunits, and sub-subunits were also composed of sub-sub-subunits. Detailed investigation shows that a bainitic relief is composed of many smaller reliefs, which correspond to a different structure of bainite, i.e., subunits, sub-subunits, and sub-sub-subunits. It is determined by STM that the surface relief arising from the formation of bainite in an Fe-C-Cr alloy is tent shaped rather than an invariant plane strain (IPS) type of surface relief. Careful observation shows that the relief obtained from a sub-sub-subunit is also tent shaped. It is discovered by STM that an α1 plate, i.e., bainite formed in Cu-Zn-Al alloys, is composed of subunits. This is also demonstrated by transmission electron microscopy (TEM). The preceding results indicate that bainitic plates in Cu-Zn-Al alloys and bainitic subunits in steels are not the smallest structural units. Based on the preceding results on the ultrafine structure and the nature of surface relief accompanying bainite, it is proposed that the bainitic structure forms through a sympathetic nucleation and ledgewise growth (SNLG) mechanism. This article shows that the SNLG mechanism can be successfully applied to interpret the complicated structure of bainite.

  8. Purification and some properties of rabbit antiovalbumin

    PubMed Central

    Ansari, Aftab A.; Salahuddin, A.

    1973-01-01

    Unlike previous reports that the ovalbumin–anti-ovalbumin complex did not dissociate completely in acid media, our results showed complete dissociation of the complex both in 1.2m-acetic acid, pH2.3, and in KCl–HCl, pH2.2, I 0.06. Thus Sephadex chromatography of the solution obtained by dissolving the antigen–antibody precipitate in these media repeatedly gave two peaks corresponding to anti-ovalbumin and ovalbumin. Further, gel-diffusion and immunoelectrophoresis experiments showed that the phosphate groups of ovalbumin are not involved in the antigenic sites. The antibody thus purified was more easily precipitated than previous preparations. The molecular weight and Stokes radius of the antibody were calculated from its gel-filtration behaviour and were found to be 148000 and 4.8nm respectively. The molecular weight determined by sodium dodecyl sulphate–polyacrylamide gel electrophoresis was essentially similar (about 0.7% lower). ImagesPLATE 1PLATE 2 PMID:4204953

  9. Iodination of glyceraldehyde 3-phosphate dehydrogenase

    PubMed Central

    Thomas, Jean O.; Harris, J. Ieuan

    1970-01-01

    1. A high degree of homology in the positions of tyrosine residues in glyceraldehyde 3-phosphate dehydrogenase from lobster and pig muscle, and from yeast, prompted an examination of the reactivity of tyrosine residues in the enzyme. 2. Iodination of the enzyme from lobster muscle with low concentrations of potassium tri-[125I]-iodide led to the identification of tyrosine residues of differing reactivity. Tyrosine-46 appeared to be the most reactive in the native enzyme. 3. When the monocarboxymethylated enzyme was briefly treated with small amounts of iodine, iodination could be confined almost entirely to tyrosine-46 in the lobster enzyme; tyrosine-39 or tyrosine-42, or both, were also beginning to react. 4. These three tyrosine residues were also those that reacted most readily in the carboxymethylated pig and yeast enzymes. 5. The difficulties in attaining specific reaction of the native enzyme are considered. 6. The differences between our results and those of other workers are discussed. ImagesPLATE 1PLATE 2 PMID:5530750

  10. Myoblasts and myoblast-conditioned medium attract the earliest spinal neurites from frog embryos.

    PubMed Central

    McCaig, C D

    1986-01-01

    A study was made of the capacity of newly segmented somites, unsegmented mesoderm and medium conditioned by each of these tissues to attract the growth of the earliest spinal neurites from the neural tube of Xenopus laevis in tissue culture. When presented with segmented somitic myoblasts or sheets of skin, spinal neurites grew selectively towards the somitic myoblasts. Neurites were not attracted specifically to somitic myoblasts from their own rostrocaudal level. A variable proportion of myoblasts from unsegmented caudal mesoderm differentiated and elongated in co-culture with neural tube and skin. These myoblasts also attracted neural outgrowths, but only if present in sufficient numbers. An agar slab containing medium conditioned by the presence of segmented myoblasts for 1 day attracted neurite outgrowths. A source of medium conditioned by the presence of undifferentiated, unsegmented myotomal mesoderm alone did not attract neurite outgrowths. Nerve growth factor (NGF) at a range of concentrations in the agar source (500-10,000 ng/ml) did not attract the earliest neurite outgrowths. It is concluded that the earliest skeletal myoblasts from Xenopus laevis embryos may attract neural outgrowths by releasing a soluble factor. Myoblasts may have to develop to the stage of somite segmentation before secretion of such an agent begins. The release of a myoblast-derived factor so early in development may assist directed nerve growth in vivo. Images Plate 1 Plate 2 PMID:3795063

  11. First geodetic measurement of convergence across the Java Trench

    NASA Technical Reports Server (NTRS)

    Tregoning, P.; Brunner, F. K.; Bock, Y.; Puntodewo, S. S. O.; Mccraffrey, R.; Genrich, J. F.; Calais, E.; Rais, J.; Subarya, C.

    1994-01-01

    Convergence across the Java Trench has been estimated for the first time, from annual Global Positioning System (GPS) measurements commencing in 1989. The directions of motion of Christmas and Cocos Island are within 1 deg of that predicted by the No-Net Rotation (NNR) NUVEL-1 plate motion model for the Australian plate although their rates are 25% and 37% less than predcited, respectively. The motion of West Java differs significantly from the NNR NUVEL-1 prediction for the Eurasian plate with a 1 deg difference in direction and a 40% increase in rate. We infer that either West Java moves with a distinct Southeast Asian plate or this region experiences plate margin deformation. The convergence of Christmas Island with respect to West Java is 67 +/- mm/yr in a direction N11 deg E +/- 4 deg which is orthogonal to the trench. The magnitude of convergence agrees well with rescaled NUVEL-1 relative plate model which predicts a value of 71 mm/yr between Australia and Eurasia. The direction of motion matches the direction inferred from earthquake slip vectors at the trench but may be more northerly than the N20 deg E +/- 3 deg predicted by NUVEL-1. On June 2, 1994, almost a year after the last GPS survey, an M(sub W) = 7.5 earthquake with slip vector direction N5 deg occurred south of central Java.

  12. Seismic evidence of divergent rifting and subsequent deformation in the southern Japan Sea, and a Cenozoic tectonic synthesis of the eastern Eurasian margin

    NASA Astrophysics Data System (ADS)

    Itoh, Yasuto; Uno, Koji; Arato, Hiroyuki

    2006-10-01

    Neogene rift system configuration for the back-arc of southwest Japan, southern rim of the Japan Sea, is argued on the basis of reflection seismic interpretation. Divergent rifting and subsequent contraction provoked by an arc-arc collisional event are manifested by the formation of faulted grabens and their inverted deformation, respectively. We identified the following four Cenozoic tectonic epochs as a decomposition process of the eastern Eurasian margin based on reliable paleomagnetic data: (1) Plate margin rearrangement on a regional left-lateral fault through southwest Japan and Sikhote Alin, which constituted a continuous geologic province before the early Tertiary differential motion; (2) Early Tertiary clockwise rotation (>20°) of the east Tan-Lu block relative to the North China block; (3) Oligocene to early Miocene divergent rifting and spreading of the Japan Sea, which divided southwest Japan from the east Tan-Lu block; (4) Middle Miocene bending and back-arc inversion of southwest Japan caused by collision with the Izu-Bonin arc. According to the estimation of relative motions during these events, a paleogeographic reconstruction is presented through Cenozoic time.

  13. Temperature- and fO2-Dependence of the Volatility and Condensation Behavior of Volatile Elements: Experimental Results

    NASA Astrophysics Data System (ADS)

    Ertel, W.; Dingwell, D. B.

    2010-12-01

    The volatility of elements is an important aspect in the Earths past, present and future: its present impact is reflected in elemental transport in the daily outgassing of volcanic vents. Its importance for understanding the earth also reaches back to the earliest periods of our solar system: nebular gases and matter underwent elemental fractionation processes based on the differences in the evaporation and condensation behaviour of matter within the solar nebula, which finally resulted in the formation of condensed matter from interplanetary dust particles up to the planets of the solar system. Precise knowledge of parameters controlling volatility as well as condensation of elements is, however, still lacking. The volatile or refractory behaviour of an element or component likely depends on the temperature and oxygen fugacity (fO2) conditions prevailing. To address this issue, a systematic study of the volatility of 18 volatile elements in respect to fO2 and temperature was launched applying a modified mechanically assisted equilibration technique (MAE): 60 g of a haplobasaltic starting composition (An-Di) was doped with up to 5000 ppm of volatile elements (Li, K, Na, Ti, Cr, Mn, Co, Cu, Cu, Zn, Ga, Rb, Cd, In, Sn, Sb, Cs, Tl) and heated to run temperature. For the fO2 dependence 2 experiments at logfO2 = -11.3 (~ IW -0.5) and - 0.7 (pure air) at a constant temperature of 1300 °C were performed, while T dependence was investigated at 1300 and 1500 °C at constant fO2 (pure air). The original MAE technique was modified by two Al2O3 plates extending from the hot spot region up to the upper, cooler regions in the muffle tube furnace, which was T calibrated prior to any experiment. In this way the plates function as condensation traps. Experiments lasted for up two weeks while experimental conditions were kept constant and monitored continuously. Up to 46 samples were taken from the melt by time-series sampling to measure the loss of volatile elements from the melt

  14. Occurrence of Potentially Pathogenic Bacterial-Endosymbionts in Acanthamoeba Spp.

    PubMed Central

    NIYYATI, Maryam; MAFI, Mahyar; HAGHIGHI, Ali; HAKEMI VALA, Mojdeh

    2015-01-01

    Background: Acanthamoeba- bacteria interactions enable pathogenic bacteria to tolerate harsh conditions and lead to transmission to the susceptible host. The present study was aimed to address the presence of bacterial endosymbionts of Acanthamoeba isolated from recreational water sources of Tehran, Iran. To the best of our knowledge this is the first study regarding occurrence of bacteria in environmental Acanthamoeba spp. in Iran. Methods: A total of 75 samples of recreational water sources were collected. Samples were cultured on non- nutrient agar 1.5% plates. Positive Acanthamoeba spp. were axenically grown. DNA extraction and PCR reaction was performed using JDP1-2 primers. All positive samples of Acanthamoeba were examined for the presence of endosymbionts using staining and molecular methods. The PCR products were then sequenced in order to determine the genotypes of Acanthamoeba and bacteria genera. Results: Out of 75 samples, 16 (21.3%) plates were positive for Acanthamoeba according to the morphological criteria. Molecular analysis revealed that Acanthamoeba belonged to T4 and T5 genotypes. Five isolates (35.7%) were positive for bacterial endosymbionts using staining method and PCR test. Sequencing of PCR products confirmed the presence of Pseudomonas aeruginosa and Agrobacterium tumefasiens. Conclusion: The presence of Acanthamoeba bearing pathogenic endosymbionts in water sources leads us to public health issues including improved sanitation and decontamination measures in recreational water sources in order to prevent amoebae-related infection. To the best of our knowledge this is the first report regarding the isolation of A. tumefasiens from Acanthamoeba in Iran and worldwide. PMID:26246815

  15. Chemical and isotope characteristics of a tufa-precipitating stream in Karwów (south-central Poland)

    NASA Astrophysics Data System (ADS)

    Duliński, Marek; Gradziński, Michał; Motyka, Jacek; Czop, Mariusz

    2016-04-01

    Chemical and isotope composition of a tufa-precipitating spring located in Karwów (south-central Poland) is described with the emphasis on the CO2-H2O-CaCO3 system. Carbonate solution is formed with participation of biogenic carbon dioxide and appears at the surface close to saturation state with respect to calcite. At the outflow of the spring the water is characterized by long-term stability of physical and chemical parameters. Along the course of the spring the tufa bed is formed as a result of CO2 outgassing. The carbon and oxygen isotope investigations were performed both on water solutions and the tufa calcite precipitated on CaCO3 plates exposed in water for different periods of time. In general, results of the 13C analyses and numerical modeling using NETPATH code suggest that calcite is precipitated close to carbon isotope equilibrium conditions except for the situations when the extreme outgassing of CO2 takes place. Several measured precipitate samples have shown distinctly lower δ18O values than expected for tufa formation under equilibrium conditions. This cannot be explained by kinetic effects known from karstic caves or lake studies as they lead to higher δ18O values of precipitated carbonates than at isotope equilibrium. Also, short-term fluctuations of water temperature cannot be responsible for the observed deviations in oxygen isotope composition of measured tufa samples from equilibrium values. Further work is needed to better understand the factors controlling 18O isotope composition of tufa deposits.

  16. Electroless plating of silver nanoparticles on porous silicon for laser desorption/ionization mass spectrometry

    NASA Astrophysics Data System (ADS)

    Yan, Hong; Xu, Ning; Huang, Wen-Yi; Han, Huan-Mei; Xiao, Shou-Jun

    2009-03-01

    An improved DIOS (desorption ionization on porous silicon) method for laser desorption/ionization mass spectrometry (LDI MS) by electroless plating of silver nanoparticles (AgNPs) on porous silicon (PSi) was developed. By addition of 4-aminothiophenol (4-ATP) into the AgNO3 plating solution, the plating speed can be slowed down and simultaneously 4-ATP self-assembled monolayers (SAMs) on AgNPs (4-ATP/AgNPs) were formed. Both AgNPs and 4-ATP/AgNPs coated PSi substrates present much higher stability, sensitivity and reproducibility for LDI MS than the un-treated porous silicon ones. Their shelf life in air was tested for several weeks to a month and their mass spectra still displayed the same high quality and sensitivity as the freshly prepared ones. And more 4-ATP SAMs partly play a role of matrix to increase the ionization efficiency. A small organic molecule of tetrapyridinporphyrin (TPyP), oligomers of polyethylene glycol (PEG 400 and 2300), and a peptide of oxytocin were used as examples to demonstrate the feasibility of the silver-plated PSi as a matrix-free-like method for LDI MS. This approach can obtain limits of detection to femtomoles for TPyP, subpicomoles for oxytocin, and picomoles for PEG 400 and 2300, comparable to the traditional matrix method and much better than the DIOS method. It simplifies the sample preparation as a matrix-free-like method without addition of matrix molecules and homogenizes the sample spread over the spot for better and more even mass signals.

  17. Characterization of a 5-fluorouracil-enriched osteoprogenitor population of the murine bone marrow.

    PubMed

    Falla, N; Van Vlasselaer; Bierkens, J; Borremans, B; Schoeters, G; Van Gorp, U

    1993-12-15

    In the presence of beta-glycerophosphate and vitamin C, cultures of normal mouse bone marrow cells form three-dimensional structures that stain positive with the Von Kossa technique and express alkaline phosphatase (ALP), collagen type I, and osteocalcin. Little is known about the characteristics and frequency of the cells that contribute to this phenomenon. Most likely, mature osteoblastic cells do not contribute to the nodule formation because no osteocalcin expressing cells are detected in the flushed marrow by in situ hybridization. Limiting dilution analysis shows that, in normal bone marrow, 1 of 2.2 x 10(5) cells has the potency to form a bone nodule and to express ALP, collagen, and osteocalcin in a temporal fashion. Upon in vivo treatment with 5-fluorouracil (5-FU), this frequency increases 12-fold, eg, 1 in 1.75 x 10(4) cells shows osteogenic activity. In comparison, fibroblast colony forming cells occur at a frequency of 1 of 2.5 x 10(4) or 1 of 5 x 10(3) plated cells in normal or 5-FU-treated marrow, respectively. Using density centrifugation, the majority of the osteoprogenitor cells in 5-FU marrow are found in the low-density (1.066 to 1.067 g/mL) fractions. In addition, these cells bind to nylon wool but not to plastic and aggregate in the presence of wheat germ agglutinin and soybean agglutinin. Scanning and transmission electron microscopy shows that the bone nodules in 5-FU marrow cultures are composed of fibroblastoid cells embedded in a mineralized collagen matrix. In conclusion, our results show that a quiescent cell population in the murine bone marrow with fibroblastoid characteristics contributes to the formation of bone-like nodules in vitro. PMID:8260697

  18. SU-E-T-232: Micro Diamonds - Determination of Their Lateral Response Function Via Gap-Beam Dose Profiles

    SciTech Connect

    Poppinga, D; Looe, H; Chofor, N; Schoenfeld, A; Fischer, J; Meyners, J; Delfs, B; Stelljes, T; Poppe, B; Verona, C; Verona-Rinati, G; Marinelli, M; Harder, D

    2014-06-01

    Purpose: The aim of this study is the measurement of the lateral response function of microDiamonds by comparison with radiochromic film dose measurement. In this study a TM60019 microDiamond (PTW Freiburg, Germany) and a prototype synthetic diamond detector with smaller sensitive volume were investigated. Methods: Two lead blocks were positioned below the gantry head of an Elekta Synergy accelerator using a gantry mount. Between the blocks two sheets of paper were fixed. The water phantom was positioned below the gantry mount, so that the block to water distance was 20 cm. The gap beam profile was measured at 5 cm water depth by radiochromic EBT3 film and diamond detectors. The film was fixed on a RW3 plate, moved by the step motor system of the phantom and digitized by an Epson 10000XL scanner using the red color channel. Results: The lateral response of the prototype diamond detector is comparable to that of film measurements, i.e. has negligible width. This corresponds to the small detector volume of the prototype detector. In contrast to this the FWHM values of the gap-beam dose profiles measured with the TM60019 detector are somewhat larger, which corresponds to the larger sensitive detector volume. Conclusion: This study has illustrated the high spatial resolution of the diamond detectors. In comparison with filmmeasured narrow-beam dose profiles, the TM60019 has a spatial resolution function of about 2 mm FWHM, whereas the FWHM for the prototype is practically negligible. However due to the low signal caused by the small sensitive volume, measurements with the prototype in clinical routine are a challenge. On the other hand the TM60019 is a good compromise between detector volume and signal output and thus a well suited detector for most clinically relevant small field situations.

  19. Diffusion control of an ion by another in LiNbO3 and LiTaO3 crystals

    PubMed Central

    Zhang, De-Long; Zhang, Qun; Qiu, Cong-Xian; Wong, Wing-Han; Yu, Dao-Yin; Yue-Bun Pun, Edwin

    2015-01-01

    Diffusion-doping is an effective, practical method to improve material properties and widen material application. Here, we demonstrate a new physical phenomenon: diffusion control of an ion by another in LiNbO3 and LiTaO3 crystals. We exemplify Ti4+/Xn+ (Xn+ = Sc3+, Zr4+, Er3+) co-diffusion in the widely studied LiNbO3 and LiTaO3 crystals. Some Ti4+/Xn+-co-doped LiNbO3 and LiTaO3 plates were prepared by co-diffusion of stacked Ti-metal and Er-metal (Sc2O3 or ZrO2) films coated onto LiNbO3 or LiTaO3 substrates. The Ti4+/Xn+-co-diffusion characteristics were studied by secondary ion mass spectrometry. In the Xn+-only diffusion case, the Xn+ diffuses considerably slower than the Ti4+. In the Ti4+/Xn+ co-diffusion case, the faster Ti4+ controls the diffusion of the slower Xn+. The Xn+ diffusivity increases linearly with the initial Ti-metal thickness and the increase depends on the Xn+ species. The phenomenon is ascribed to the generation of additional defects induced by the diffusion of faster Ti4+ ions, which favors and assists the subsequent diffusion of slower Xn+ ion. For the diffusion system studied here, it can be utilized to substantially shorten device fabrication period, improve device performance and produce new materials. PMID:25941037

  20. Research, development, and demonstration of nickel-iron batteries for electric vehicle propulsion. Annual report, 1979

    SciTech Connect

    Not Available

    1980-06-01

    The program has progressed to the stage of evaluating full-sized (220 Ah) cells, multicell modules, and 22 kWh batteries. Nickel electrodes that display stable capacities of up to 24 Ah/plate (at C/3 drain rate) at design thickness (2.5 mm) in tests at 200/sup +/ test cycles. Iron electrodes of the composite-type are also delivering 24 Ah/plate (at C/3) at target thickness (1.0 mm). Iron plates are displaying capacity stability for 300/sup +/ test cycles in continuing 3 plate cell tests. Best finished cells are delivering 57 to 63 Wh/kg at C/3, based on cell weights of the finished cells, and in the actual designed cell volume. 6-cell module (6-1) performance has demonstrated 239 Ah, 1735 Wh, 53 WH/kg at the C/3 drain rate. This module is now being evaluated at the National Battery Test Laboratory. The 2 x 4 battery has been constructed, tested, and delivered for engineering test and evaluation. The battery delivered 22.5 kWh, as required (199 Ah discharge at 113 V-bar) at the C/3 drain rate. The battery has performed satisfactorily under dynamometer and constant current drain tests. Some cell problems, related to construction, necessitated changing 3 modules, but the battery is now ready for further testing. Reduction in nickel plate swelling (and concurrent stack electrolyte starvation), to improve cycling, is one area of major effort to reach the final battery objectives. Pasted nickel electrodes are showing promise in initial full-size cell tests and will continue to be evaluated in finished cells, along with other technology advancements. 30 figures, 14 tables.

  1. A previously undescribed pathway for pyrimidine catabolism

    PubMed Central

    Loh, Kevin D.; Gyaneshwar, Prasad; Markenscoff Papadimitriou, Eirene; Fong, Rebecca; Kim, Kwang-Seo; Parales, Rebecca; Zhou, Zhongrui; Inwood, William; Kustu, Sydney

    2006-01-01

    The b1012 operon of Escherichia coli K-12, which is composed of seven unidentified ORFs, is one of the most highly expressed operons under control of nitrogen regulatory protein C. Examination of strains with lesions in this operon on Biolog Phenotype MicroArray (PM3) plates and subsequent growth tests indicated that they failed to use uridine or uracil as the sole nitrogen source and that the parental strain could use them at room temperature but not at 37°C. A strain carrying an ntrB(Con) mutation, which elevates transcription of genes under nitrogen regulatory protein C control, could also grow on thymidine as the sole nitrogen source, whereas strains with lesions in the b1012 operon could not. Growth-yield experiments indicated that both nitrogens of uridine and thymidine were available. Studies with [14C]uridine indicated that a three-carbon waste product from the pyrimidine ring was excreted. After trimethylsilylation and gas chromatography, the waste product was identified by mass spectrometry as 3-hydroxypropionic acid. In agreement with this finding, 2-methyl-3-hydroxypropionic acid was released from thymidine. Both the number of available nitrogens and the waste products distinguished the pathway encoded by the b1012 operon from pyrimidine catabolic pathways described previously. We propose that the genes of this operon be named rutA–G for pyrimidine utilization. The product of the divergently transcribed gene, b1013, is a tetracycline repressor family regulator that controls transcription of the b1012 operon negatively. PMID:16540542

  2. Osteotomy and intramedullary nailing for the correction of progressive deformity in vitamin D-resistant hypophosphataemic rickets.

    PubMed

    Eyres, K S; Brown, J; Douglas, D L

    1993-02-01

    We have reviewed the results of surgical treatment of vitamin D-resistant hypophosphataemic rickets (VDRR) and describe a technique of corrective osteotomy and intramedullary nailing. From 1978 to 1986, epiphysiodesis (n = 4) and osteotomy (n = 8) was performed in 6 children (mean age 13, range 10-16 years) for the correction of progressive lower limb deformity. Realignment and internal fixation of a pathological fracture of the femur was performed in an adult (aged 24). Epiphysiodesis resulted in recurrent deformity in all patients and reapplication of staples for loosening was required in three. Corrective osteotomies were secured with staples (n = 3), plates (n = 4), or plaster alone (n = 1) and were complicated by non-union in one patient, and recurrent deformity in two patients. Double-plating of the femoral fracture resulted in union but recurrent deformity. Compliance to treatment with phosphate and vitamin D was variable. In order to manage progressive recurrent deformity, we have performed corrective osteotomy and closed intramedullary nailing of the tibia (n = 2) and femur (n = 3) in 4 skeletally mature patients (mean age 31). All osteotomies united and no complications were encountered. Deformity has been corrected in all cases and all patients are satisfied with the outcome at least 2 years after surgery. We conclude that rigid methods of fixation spanning the whole length of the bone are required to maintain limb alignment in skeletally mature patients with VDRR. Since the quality of bone in VDRR is variable, experience with intramedullary techniques is essential. We stress the importance of appropriate medical therapy throughout the treatment of these patients. PMID:8382289

  3. Emissions of metals, chromium and nickel species, and organics from municipal waste-water-sludge incinerators. Volume 8. Site 9 emission-test report. Final report, 1989-91

    SciTech Connect

    DeWees, W.G.; Segall, R.R.; Lewis, F.M.

    1992-03-01

    Site 9 is a secondary plant designed for 15 million gallons per day (MGD) of wastewater flow. The sludge incinerator at Site 9 is a seven (7) hearth, multiple hearth furnace (MHF) built by Nichols Engineering in 1974 controlled by an adjustable throat venturi, with a nominal pressure drop of 20 in. w.c.. After leaving the venturi, the gases pass upward through a three (3) plate tray scrubber with a Chevron mist eliminator. A 10 ft. x 10 ft., upflow, wet electrostatic precipitator, manufacturer by Beltran Associates, Inc., was installed during the first week of testing. The ratio of nickel subsulfide to total nickel in the emission at Site 9 is extremely low, with the sulfidic nickel species being measured at less than detection limit (about 1 to 2 percent of the total nickel). The ratio of hexavalent chromium to total chromium in the emissions at Site 9 was significantly higher that had been anticipated. Site 9 had only two semivolatile organic compounds detected under normal and improved combustion conditions benzyl alcohol and benzoic acid. Several additional compounds were found in the emissions for the normal or improved combustion conditions at Site 9; these compounds were 1,4-dichlorobenzene, 1,2-dichlorobenzene, 2-nitrophenol, 1,2,4-Trichlorobenzene, naphthalene, 2-methylnaphthalene, dibenzofuran, phenanthrene, bis(2-ethylhexyl)phthalate, phenol, 4-methylphenol, and 4-nitrophenol. The volatile organic compounds detected in the Site 9 multiple hearth incinerator emissions were similar to the compounds reported for Sites 1, 2, and 4 (other multiple hearth incinerator tested). Carbon tetrachloride and carbon tetrachloride, reported in the emissions at the other three sites, were not found in the emissions from Site 9.

  4. Decontamination of laboratory microbiological waste by steam sterilization.

    PubMed Central

    Rutala, W A; Stiegel, M M; Sarubbi, F A

    1982-01-01

    A steam sterilizer (autoclave) was tested to determine the operating parameters that affected sterilization of microbiological waste. Tests involved standardized loads (5, 10 ad 15 lb [ca. 2.27, 4.54, and 6.80 kg, respectively]) contaminated petri plates in autoclave bags placed in polypropylene or stainless steel containers. Thermal and biological data were obtained by using a digital potentiometer and a biological indicator containing spores of Bacillus stearothermophilus, respectively. The transfer of heat was more efficient when smaller loads of microbiological waste were tested and stainless steel rather than polypropylene containers were used. A single bag with the sides rolled down to expose the top layer of petri plates allowed heat to pass better than did a single bag with the top constricted by a twist-tie. The presence of water in the autoclave bag did not significantly improve heat-up time in stainless steel or polypropylene containers. The results of biological tests substantiated the temperature data. When 10 or 15 lb of microbiological waste was exposed to various test conditions, the only condition that ensured the destruction of B. stearothermophilus involved the use of a stainless steel container (with or without water) for 90 min. Autoclaving for 45 min resulted in the destruction of bacteria included in 10 lb (136 +/- 3 plates) or 15 lb (205 +/- 6 plates) of microbiological waste when stainless steel containers with or without water or polypropylene containers with water used, whereas 60 min was required to kill all bacteria if polypropylene containers without water were used. PMID:7103486

  5. Decontamination of laboratory microbiological waste by steam sterilization.

    PubMed

    Rutala, W A; Stiegel, M M; Sarubbi, F A

    1982-06-01

    A steam sterilizer (autoclave) was tested to determine the operating parameters that affected sterilization of microbiological waste. Tests involved standardized loads (5, 10 ad 15 lb [ca. 2.27, 4.54, and 6.80 kg, respectively]) contaminated petri plates in autoclave bags placed in polypropylene or stainless steel containers. Thermal and biological data were obtained by using a digital potentiometer and a biological indicator containing spores of Bacillus stearothermophilus, respectively. The transfer of heat was more efficient when smaller loads of microbiological waste were tested and stainless steel rather than polypropylene containers were used. A single bag with the sides rolled down to expose the top layer of petri plates allowed heat to pass better than did a single bag with the top constricted by a twist-tie. The presence of water in the autoclave bag did not significantly improve heat-up time in stainless steel or polypropylene containers. The results of biological tests substantiated the temperature data. When 10 or 15 lb of microbiological waste was exposed to various test conditions, the only condition that ensured the destruction of B. stearothermophilus involved the use of a stainless steel container (with or without water) for 90 min. Autoclaving for 45 min resulted in the destruction of bacteria included in 10 lb (136 +/- 3 plates) or 15 lb (205 +/- 6 plates) of microbiological waste when stainless steel containers with or without water or polypropylene containers with water used, whereas 60 min was required to kill all bacteria if polypropylene containers without water were used. PMID:7103486

  6. The effect of cleaning substances on the surface of denture base material

    PubMed Central

    Žilinskas, Juozas; Junevičius, Jonas; Česaitis, Kęstutis; Junevičiūtė, Gabrielė

    2013-01-01

    Bakcground The aim of this study was to evaluate the effect of substances used for hygienic cleaning of dentures on the surface of the denture base material. Material/Methods Meliodent Heat Cure (Heraeus-Kulzer, Germany) heat-polymerized acrylic resin was used to produce plates with all the characteristics of removable denture bases (subsequently, “plates”). Oral-B Complete toothbrushes of various brush head types were fixed to a device that imitated tooth brushing movements; table salt and baking soda (frequently used by patients to improve tooth brushing results), toothpaste (“Colgate Total”), and water were also applied. Changes in plate surfaces were monitored by measuring surface reflection alterations on spectrometry. Measurements were conducted before the cleaning and at 2 and 6 hours after cleaning. Results No statistically significant differences were found between the 3 test series. All 3 plates used in the study underwent statistically significant (p<0.05changed) – the reflection became poorer. The plates were most affected by the medium-bristle toothbrush with baking soda – the total reflection reduction was 4.82±0.1%; among toothbrushes with toothpaste, the hard-type toothbrush had the greatest reflection-reducing effect – 4.6±0.05%, while the toothbrush with table salt inflicted the least damage (3.5 ± 0.16%) due to the presence of rounded crystals between the bristles and the resin surface. Toothbrushes with water had a uniform negative effect on the plate surface – 3.89±0.07%. Conclusions All substances used by the patients caused surface abrasion of the denture base material, which reduced the reflection; a hard toothbrush with toothpaste had the greatest abrasive effect, while soft toothbrushes inflicted the least damage. PMID:24326781

  7. The three cortical membranes of the gregarines (parasitic protozoa). Characterization of the membrane proteins of Gregarina blaberae*

    PubMed Central

    Philippe, M.; Schrével, J.

    1982-01-01

    Gregarines, which are parasitic protozoa living in invertebrates, possess a cortical structure specific to their vegetative stage: namely two additional cytomembranes are lying just under the plasma membrane. This cortical complex has been isolated by centrifugation on discontinuous sucrose gradients and characterized chemically. Its integrity was tested by electron microscopy. Ghost proteins were resolved by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. About 30 polypeptides of mol.wt. 15000–300000 were present in this fraction and four glycoproteins were detected after periodate/Schiff staining. Ten major proteins were labelled after lactoperoxidase-catalysed iodination. The GP2 glycoprotein (41000–49000 apparent mol.wt.) appears to be a major component of the cell surface. Effects of trypsin and Pronase digestion on ghosts and cells were monitored by gel electrophoresis and by electron microscopy. Ghosts treated with low trypsin or Pronase concentrations (10–25μg/ml) became drastically disorganized; many proteins were vigorously attacked in comparison with those of control ghosts. Variations in proteinase-sensitivity of proteins are pointed out. The GP3 glycoprotein (130000–160000 apparent mol.wt.) seemed to be the only glycoprotein released from the cell surface by trypsin. Whole cells treated under the same conditions or with higher proteinase concentrations (up to 1mg/ml) do not exhibit morphological modifications of the cell surface; furthermore, no discernible cleavage of membrane proteins was indicated by electrophoretograms. It is postulated that cell-surface proteins are protected by the dense carbohydrate cell coat. By using various different methods (change of ionic strength, detergent, denaturing agent, labelling experiment) it was possible to localize several major proteins within the protozoon cortical membranes. ImagesPLATE 1Fig. 1.Fig. 3.PLATE 2(a)PLATE 2(b)Fig. 4.Fig. 5.Fig. 6. PMID:6807283

  8. Gases and water isotopes in a geochemical section across the Larderello, Italy, geothermal field

    USGS Publications Warehouse

    Truesdell, A.H.; Nehring, N.L.

    1978-01-01

    Steam samples from six wells (Colombaia, Pineta, Larderello 57, Larderello 155, Gabbro 6, and Gabbro 1) in a south to north section across the Larderello geothermal field have been analyzed for inorganic and hydrocarbon gases and for oxygen-18 and deuterium of steam. The wells generally decrease in depth and increase in age toward the south. The steam samples are generally characterized by (1) Total gas contents increasing south to north from 0.003 to 0.05 mole fraction; (2) Constant CO2 (95??2 percent); near constant H2S (1.6??0.8), N2 (1.2??0.8), H2 (2??1), CH4 (1.2??1), and no O2 in the dry gas; (3) Presence of numerous, straight chain and branched C2 to C6 hydrocarbons plus benzene in amounts independent of CH4 contents with highest concentrations in the deeper wells; (4) Oxygen-18 contents of steam increasing south to north from -5.0??? to -0.4??? with little change in deuterium (-42??2???). These observations are interpreted as showing: (1) Decreasing gas contents with amount of production because the proportion of steam boiled from liquid water increases with production; (2) Synthesis of CH4 from H2 and CO2 with CO2 and H2 produced by thermal metamorphism and rock-water reactions; (3) Extraction of C2 to C6 hydrocarbons from rock organic matter; (4) Either oxygen isotope exchange followed by distillation of steam from the north toward the south (2 plates at ???220??C) or mixture of deeper more-exchange waters from the north with shallow, less-exchanged recharging waters from the south. ?? 1978 Birkha??user Verlag.

  9. Geophysical interpretation of satellite laser ranging measurements of crustal movement in California

    NASA Technical Reports Server (NTRS)

    Cohen, S. C.

    1984-01-01

    As determined by satellite laser ranging the rate of contraction of a 900 kilometer baseline between sites located near Quincy in northern California and San Diego in southern California is about 61 to 65 mm/yr with a formal uncertainty of about 10 mm/yr. The measured changes in baseline length are a manifestation of the relative motion between the North America and Pacific tectonic plates. This long baseline result is compared to measurements made by more conventional means on shorter baselines. Additional information based on seismicity, geology, and theoretical modelling is also analyzed. Deformation lying within a few tens of kilometers about the major faults in southern California accounts for most, but not all of the observed motion. Further motion is attributable to a broader scale deformation in southern California. Data suggesting crustal movements north of the Garlock fault, in and near the southern Sierra Nevada and local motion at an observatory are also critically reviewed. The best estimates of overall motion indicated by ground observations lie between 40 and 60 mm/yr. This lies within one or two standard deviations of that deduced by satellite ranging but the possibility of some unresolved deficit cannot be dismissed. The long time scale RM2 plate tectonic model of Minster and Jordan predicts a contraction between 47 and 53 mm/yr depending on the extension rate of the Basin and Range. Thus the ground based observations, satellite laser ranging (SLR) results, and RM2 rates differ at about the 10 mm/yr level and are consistent with one another within the data and model uncertainties.

  10. Switching between alternative responses of the lithosphere to continental collision

    NASA Astrophysics Data System (ADS)

    Baes, Marzieh; Govers, Rob; Wortel, Rinus

    2011-12-01

    We study possible responses to arc-continent or continent-continent collision using numerical models. Our short-term integration models show that the initial stage of deformation following continental collision is governed by the competition between three potential weakness zones: (1) mantle wedge, (2) plate interface and (3) lower continental crust. Depending on which of these is the weakest zone in the system, three different responses can be recognized: (1) subduction polarity reversal, (2) continuation of subduction and (3) delamination and back stepping. Subduction polarity reversal occurs if the mantle wedge is the weakest zone in the system. This happens only if the viscosity of the mantle wedge is at least one order of magnitude lower than the average viscosity of the lithosphere. In continent-continent collision, one additional condition needs to be satisfied for subduction polarity reversal to occur: for the subducting lithosphere the ratio of the viscosity of the lower continental crust to the viscosity of the upper lithospheric mantle must be equal to or higher than 0.006. The time required for polarity reversal depends on several parameters: the convergence rate, the sinking velocity of the detached slab and the relative strength of the mantle wedge, arc and backarc. The response to collision is continued subduction if the plate interface is the weakest zone, and is delamination and back stepping if the lower continental crust is the weakest area in the system. Our finding that a low-viscosity wedge is a prerequisite for a reversal of subduction polarity agrees with inferences about regions for which subduction polarity reversal has been proposed.

  11. A specific collagenase from rabbit fibroblasts in monolayer culture

    PubMed Central

    Werb, Zena; Burleigh, Mary C.

    1974-01-01

    1. Explants of rabbit skin and synovium in tissue culture secreted a specific collagenase into their culture media. Primary cultures of fibroblast-like cells, which were obtained from these tissues and maintained in culture for up to 14 subculture passages, also secreted high activities of a specific collagenase into serum-free culture medium. Secretion of enzyme activity from the cell monolayer was at constant rate for over 100h and continued for up to 8 days in serum-free culture medium. The enzymic activity released was proportional to the number of cells in the monolayer. 2. The fibroblast collagenase was maximally active between pH7 and 8. At 24°C the collagenase decreased the viscosity of collagen in solution by 60%. The collagen molecule was cleaved into three-quarters and one-quarter length fragments as demonstrated by electron microscopy of segment-long-spacing crystallites (measured as native collagen molecules aligned with N-termini together along the long axis), and by polyacrylamide-gel electrophoresis of the denatured products. The collagenase hydrolysed insoluble collagen, reconstituted collagen fibrils and gelatin, but had no effect on haemoglobin or Pz-Pro-Leu-Gly-Pro-d-Arg (where Pz=4-phenylazobenzyloxycarbonyl). 3. The fibroblast collagenase was partially purified by gel filtration and the molecular weight was estimated as 38000. The activity of the partially purified enzyme was stimulated by 4-chloromercuribenzoate, inhibited by EDTA, cysteine, 1,10-phenanthroline and serum, but was unaffected by di-isopropyl phosphorofluoridate, Tos-LysCH2Cl and pepstatin. 4. Long-term cell cultures originating from rabbit skin or synovium from rabbits with experimentally induced arthritis also secreted specific collagenase. Human fibroblasts released only very small amounts of collagenase. ImagesPLATE 2PLATE 1 PMID:4363113

  12. Sympathetic innervation and excitability of arterioles originating from the rat middle cerebral artery.

    PubMed Central

    Hill, C E; Hirst, G D; Silverberg, G D; van Helden, D F

    1986-01-01

    The densities of the adrenergic innervation of the internal carotid and middle cerebral arteries and their extracerebral branches have been determined using fluorescence histochemistry. The density of the nerve plexus on the internal carotid artery was greater than that of the middle cerebral artery. The density of the plexus on the middle cerebral artery decreased with increasing distance from its origin. The density and the peripheral extent of the nerve fibre plexus on the arterioles arising from the carotid artery were greater than those arising from the middle cerebral artery. On any arteriole the density of innervation decreased with increasing distance from its origin. The passive electrical properties of proximal and distal middle cerebral arteriolar segments were compared. Both proximal and distal arteriolar segments had similar resistances and time constants in the order of 100 M omega and 250 ms respectively. Small regenerative responses could be elicited in all proximal middle cerebral arteriolar segments but only in a proportion of corresponding distal segments. The addition of external tetraethylammonium ions (TEA) provided much larger regenerative responses. Action potentials in proximal middle cerebral arteriolar segments had larger peak amplitudes and faster rise times than those of corresponding distal segments. Distal carotid arteriolar segments had similar voltage-dependent excitability as proximal segments of middle cerebral arterioles but generated less inward current for a given voltage step. There was a direct correlation between the density of innervation and the voltage-dependent excitability of arteriolar smooth muscle cells. The possibility that the presence of nerves is correlated with the density of calcium channels is discussed. Images PLATE 2 PLATE 1 PMID:3701653

  13. Formation of {beta}-nickel hydroxide plate-like structures under mild conditions and their optical properties

    SciTech Connect

    Moura, A.P. de; Lima, R.C.; Paris, E.C.; Li, M.S.; Varela, J.A.; Longo, E.

    2011-10-15

    Nanostructural {beta}-nickel hydroxide ({beta}-Ni(OH){sub 2}) plates were prepared using the microwave-hydrothermal (MH) method at a low temperature and short reaction times. An ammonia solution was employed as the coordinating agent, which reacts with [Ni(H{sub 2}O){sub 6}]{sup 2+} to control the growth of {beta}-Ni(OH){sub 2} nuclei. A trigonal {beta}-Ni(OH){sub 2} single phase was observed by X-ray diffraction (XRD) analyses, and the crystal cell was constructed with structural parameters and atomic coordinates obtained from Rietveld refinement. Field emission scanning electron microscopy (FE-SEM) images revealed that the samples consisted of hexagonal-shaped nanoplates with a different particle size distribution. Broad absorption bands assigned as transitions of Ni{sup 2+} in oxygen octahedral sites were revealed by UV-vis spectra. Photoluminescence (PL) properties observed with a maximum peak centered in the blue-green region were attributed to different defects, which were produced during the nucleation process. We present a growth process scheme of the {beta}-Ni(OH){sub 2} nanoplates. - Graphical abstract: Nanostructural {beta}-Ni(OH){sub 2} crystalline powders were prepared by rapid microwave-hydrothermal method for 1, 8 and 32 min. The hexagonal-shaped nanoplates obtained presented PL emission in the blue-green region and each decomposed component represents a different type of electronic transition, which can be linked to the structural arrangement or surface defects. Highlights: > Ammonia solution to control the growth of {beta}-Ni(OH){sub 2} nuclei. > Regular plates-shape related to crystallization-dissolution-recrystallization. > The surface states and lattice defects generated in growth mechanism of crystals. > Different defects produced in the growth process responsible by photoluminescence. > Each component of photoluminescence curve linked to structural arrangement or surface defects.

  14. Effect of Elevated Atmospheric CO2 and Temperature on the Disease Severity of Rocket Plants Caused by Fusarium Wilt under Phytotron Conditions

    PubMed Central

    Chitarra, Walter; Siciliano, Ilenia; Ferrocino, Ilario; Gullino, Maria Lodovica; Garibaldi, Angelo

    2015-01-01

    The severity of F. oxysporum f.sp. conglutinans on rocket plants grown under simulated climate change conditions has been studied. The rocket plants were cultivated on an infested substrate (4 log CFU g-1) and a non-infested substrate over three cycles. Pots were placed in six phytotrons in order to simulate different environmental conditions: 1) 400–450 ppm CO2, 18–22°C; 2) 800–850 ppm CO2, 18–22°C; 3) 400–450 ppm CO2, 22–26°C, 4) 800–850 ppm CO2, 22–26°C, 5) 400–450 ppm CO2, 26–30°C; 6) 800–850 ppm CO2, 26–30°C. Substrates from the infested and control samples were collected from each phytotron at 0, 60 and 120 days after transplanting. The disease index, microbial abundance, leaf physiological performances, root exudates and variability in the fungal profiles were monitored. The disease index was found to be significantly influenced by higher levels of temperature and CO2. Plate counts showed that fungal and bacterial development was not affected by the different CO2 and temperature levels, but a significant decreasing trend was observed from 0 up to 120 days. Conversely, the F. oxysporum f.sp. conglutinans plate counts did not show any significantly decrease from 0 up to 120 days. The fungal profiles, evaluated by means of polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE), showed a relationship to temperature and CO2 on fungal diversity profiles. Different exudation patterns were observed when the controls and infested plants were compared, and it was found that both CO2 and temperature can influence the release of compounds from the roots of rocket plants. In short, the results show that global climate changes could influence disease incidence, probably through plant-mediated effects, caused by soilborne pathogens. PMID:26469870

  15. Effect of Elevated Atmospheric CO2 and Temperature on the Disease Severity of Rocket Plants Caused by Fusarium Wilt under Phytotron Conditions.

    PubMed

    Chitarra, Walter; Siciliano, Ilenia; Ferrocino, Ilario; Gullino, Maria Lodovica; Garibaldi, Angelo

    2015-01-01

    The severity of F. oxysporum f.sp. conglutinans on rocket plants grown under simulated climate change conditions has been studied. The rocket plants were cultivated on an infested substrate (4 log CFU g-1) and a non-infested substrate over three cycles. Pots were placed in six phytotrons in order to simulate different environmental conditions: 1) 400-450 ppm CO2, 18-22°C; 2) 800-850 ppm CO2, 18-22°C; 3) 400-450 ppm CO2, 22-26°C, 4) 800-850 ppm CO2, 22-26°C, 5) 400-450 ppm CO2, 26-30°C; 6) 800-850 ppm CO2, 26-30°C. Substrates from the infested and control samples were collected from each phytotron at 0, 60 and 120 days after transplanting. The disease index, microbial abundance, leaf physiological performances, root exudates and variability in the fungal profiles were monitored. The disease index was found to be significantly influenced by higher levels of temperature and CO2. Plate counts showed that fungal and bacterial development was not affected by the different CO2 and temperature levels, but a significant decreasing trend was observed from 0 up to 120 days. Conversely, the F. oxysporum f.sp. conglutinans plate counts did not show any significantly decrease from 0 up to 120 days. The fungal profiles, evaluated by means of polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE), showed a relationship to temperature and CO2 on fungal diversity profiles. Different exudation patterns were observed when the controls and infested plants were compared, and it was found that both CO2 and temperature can influence the release of compounds from the roots of rocket plants. In short, the results show that global climate changes could influence disease incidence, probably through plant-mediated effects, caused by soilborne pathogens. PMID:26469870

  16. A polarization-based frequency scanning interferometer and the signal processing acceleration method based on parallel processing architecture

    NASA Astrophysics Data System (ADS)

    Lee, Seung Hyun; Kim, Min Young

    FSI system, one of the most promising optical surface measurement techniques, generally results in superior optical performance comparing with other 3-dimensional measuring methods as its hardware structure is fixed in operation and only the light frequency is scanned in a specific spectral band without vertical scanning of the target surface or the objective lens. FSI system collects a set of images of interference fringe by changing the frequency of light source. After that, it transforms intensity data of acquired image into frequency information, and calculates the height profile of target objects with the help of frequency analysis based on FFT. However, it still suffers from optical noise from target surface and relatively long processing time due to the number of images acquired in frequency scanning phase. First, a polarization-based frequency scanning interferometry (PFSI) is proposed for optical noise robustness. It consists of tunable laser for light source, λ/4 plate in front of reference mirror, λ/4 plate in front of target object, polarizing beam splitter, polarizer in front of image sensor, polarizer in front of the fiber coupled light source, λ/2 plate between PBS and polarizer of the light source. Using the proposed system, we can solve the problem low contrast of acquired fringe image by using polarization technique. Also, we can control light distribution of object beam and reference beam. Second, the signal processing acceleration method is proposed for PFSI, based on parallel processing architecture, which consists of parallel processing hardware and software such as GPU (Graphic Processing Unit) and CUDA (Compute Unified Device Architecture). As a result, the processing time reaches into tact time level of real-time processing. Finally, the proposed system is evaluated in terms of accuracy and processing speed through a series of experiment and the obtained results show the effectiveness of the proposed system and method.

  17. Mass production of the large-sized nuclear plate for J-PARC E07

    NASA Astrophysics Data System (ADS)

    Ito, Hiroki; Nakazama, Kazuma; Hoshino, Kaoru; Yoshida, Jyunya; Tint, Khin Than; Soe, Mint Kyaw; Kinbara, Shinji; Mishina, Akihiro; Endo, Yoko; Kobayashi, Hidetaka; J-PARC E07 Collaboration

    2014-09-01

    In J-PARC E07, about 102 double lambda hypernuclei will be detected, which is 10 times or more than that of the KEK PS-E373 experiment. Therefore, it is necessary for large-scale emulsion plates to avoid time-consuming job for exchange emulsion stack in beam exposure. We also use huge amount of emulsion gel with weight of 2.1 t, which is about 3 times' quantity used for E373. Nuclear emulsion plate is made of photographic emulsion gel as a dry film. Melted gel in 40°C is poured on a thin polystyrene film in the size of 710 × 700 mm2. These sheets were dried slowly for two days in drying cabinet under 28°C and RH. 75%. After drying, the surface was coated by thin gelatin layer with 0.3 μm thickness. Regarding the 2nd face, it was poured and coated in the same manner. Finally we dry it well under 25°C and RH. 60% and cut into four 350 × 345 mm2 plates. We evaluated the performance about these plates. The length of upper, lower, right-hand and left-hand side are 345.08 +/- 0.05 mm, 345.23 +/- 0.13 mm, 350.03 +/- 0.04 mm, and 350.80 +/- 0.05 mm, respectively. The density is 3.676 +/- 0.032 g/cm3, enough quality for the experiment.

  18. X-ray imaging using digital cameras

    NASA Astrophysics Data System (ADS)

    Winch, Nicola M.; Edgar, Andrew

    2012-03-01

    The possibility of using the combination of a computed radiography (storage phosphor) cassette and a semiprofessional grade digital camera for medical or dental radiography is investigated. We compare the performance of (i) a Canon 5D Mk II single lens reflex camera with f1.4 lens and full-frame CMOS array sensor and (ii) a cooled CCD-based camera with a 1/3 frame sensor and the same lens system. Both systems are tested with 240 x 180 mm cassettes which are based on either powdered europium-doped barium fluoride bromide or needle structure europium-doped cesium bromide. The modulation transfer function for both systems has been determined and falls to a value of 0.2 at around 2 lp/mm, and is limited by light scattering of the emitted light from the storage phosphor rather than the optics or sensor pixelation. The modulation transfer function for the CsBr:Eu2+ plate is bimodal, with a high frequency wing which is attributed to the light-guiding behaviour of the needle structure. The detective quantum efficiency has been determined using a radioisotope source and is comparatively low at 0.017 for the CMOS camera and 0.006 for the CCD camera, attributed to the poor light harvesting by the lens. The primary advantages of the method are portability, robustness, digital imaging and low cost; the limitations are the low detective quantum efficiency and hence signal-to-noise ratio for medical doses, and restricted range of plate sizes. Representative images taken with medical doses are shown and illustrate the potential use for portable basic radiography.

  19. Selection of an Alternate Biocide for the ISS Internal Thermal Control System Coolant, Phase 2

    NASA Technical Reports Server (NTRS)

    Wilson, Mark E.; Cole, Harold; Weir, Natalee; Oehler, Bill; Steele, John; Varsik, Jerry; Lukens, Clark

    2004-01-01

    The ISS (International Space Station) ITCS (Internal Thermal Control System) includes two internal coolant loops that utilize an aqueous based coolant for heat transfer. A silver salt biocide had previously been utilized as an additive in the coolant formulation to control the growth and proliferation of microorganisms within the coolant loops. Ground-based and in-flight testing demonstrated that the silver salt was rapidly depleted, and did not act as an effective long-term biocide. Efforts to select an optimal alternate biocide for the ITCS coolant application have been underway and are now in the final stages. An extensive evaluation of biocides was conducted to down-select to several candidates for test trials and was reported on previously. Criteria for that down-select included: the need for safe, non-intrusive implementation and operation in a functioning system; the ability to control existing planktonic and biofilm residing microorganisms; a negligible impact on system-wetted materials of construction; and a negligible reactivity with existing coolant additives. Candidate testing to provide data for the selection of an optimal alternate biocide is now in the final stages. That testing has included rapid biocide effectiveness screening using Biolog MT2 plates to determine minimum inhibitory concentration (amount that will inhibit visible growth of microorganisms), time kill studies to determine the exposure time required to completely eliminate organism growth, materials compatibility exposure evaluations, coolant compatibility studies, and bench-top simulated coolant testing. This paper reports the current status of the effort to select an alternate biocide for the ISS ITCS coolant. The results of various test results to select the optimal candidate are presented.

  20. Wavefront-Error Performance Characterization for the James Webb Space Telescope (JWST) Integrated Science Instrument Module (ISIM) Science Instruments

    NASA Technical Reports Server (NTRS)

    Aronstein, David L.; Smith, J. Scott; Zielinski, Thomas P.; Telfer, Randal; Tournois, Severine C.; Moore, Dustin B.; Fienup, James R.

    2016-01-01

    The science instruments (SIs) comprising the James Webb Space Telescope (JWST) Integrated Science Instrument Module (ISIM) were tested in three cryogenic-vacuum test campaigns in the NASA Goddard Space Flight Center (GSFC)'s Space Environment Simulator (SES). In this paper, we describe the results of optical wavefront-error performance characterization of the SIs. The wavefront error is determined using image-based wavefront sensing (also known as phase retrieval), and the primary data used by this process are focus sweeps, a series of images recorded by the instrument under test in its as-used configuration, in which the focal plane is systematically changed from one image to the next. High-precision determination of the wavefront error also requires several sources of secondary data, including 1) spectrum, apodization, and wavefront-error characterization of the optical ground-support equipment (OGSE) illumination module, called the OTE Simulator (OSIM), 2) plate scale measurements made using a Pseudo-Nonredundant Mask (PNRM), and 3) pupil geometry predictions as a function of SI and field point, which are complicated because of a tricontagon-shaped outer perimeter and small holes that appear in the exit pupil due to the way that different light sources are injected into the optical path by the OGSE. One set of wavefront-error tests, for the coronagraphic channel of the Near-Infrared Camera (NIRCam) Longwave instruments, was performed using data from transverse translation diversity sweeps instead of focus sweeps, in which a sub-aperture is translated andor rotated across the exit pupil of the system.Several optical-performance requirements that were verified during this ISIM-level testing are levied on the uncertainties of various wavefront-error-related quantities rather than on the wavefront errors themselves. This paper also describes the methodology, based on Monte Carlo simulations of the wavefront-sensing analysis of focus-sweep data, used to establish the

  1. The formation of ferritin from apoferritin. Kinetics and mechanism of iron uptake

    PubMed Central

    Macara, I. G.; Hoy, T. G.; Harrison, Pauline M.

    1972-01-01

    Ferritin has a high capacity as an iron store, incorporating some 4500 iron atoms as a microcrystalline ferric oxide hydrate. Starting from apoferritin, or ferritin of low iron content, Fe2+ and an oxidizing agent, the uptake of iron can be recorded spectrophotometrically. Progress curves were obtained and the reconstituted ferritin was shown by several physical methods to be similar to natural ferritin. The progress curves of iron uptake by apoferritin are sigmoidal; those for ferritins of low iron content are hyperbolic. The rate of iron uptake is dependent on the amount of iron already present in the molecule. The distribution of iron contents among reconstituted ferritin molecules is inhomogeneous. These findings are interpreted in terms of a crystal growth model. The surface area of the crystallites forming inside the protein increases until the molecule is half full, and then declines. This surface controls the rate at which new material is deposited. The experimental results can best be accounted for by a two-stage mechanism, an initial slow `nucleation' stage, which is apparently zero order with respect to [Fe2+], followed by a more rapid `growth' stage. The rate of Fe2+ oxidation is increased in the presence of apoferritin as compared with controls. Ferritin can therefore be regarded as an enzyme to which the product remains firmly attached. The protein appears to increase the rate of `nucleation'. The apparent zero order of this stage suggests the presence of binding sites on the protein, which are saturated with respect to Fe2+. These sites are presumed also to be oxidation sites. The oxidation and subsequent formation of the ferric oxide hydrate may proceed according to one of three alternative models. ImagesPLATE 1PLATE 2 PMID:5075227

  2. A study of the physicochemical interactions between biliary lipids and chlorpromazine hydrochloride. Bile-salt precipitation as a mechanism of phenothiazine-induced bile secretory failure.

    PubMed Central

    Carey, M C; Hirom, P C; Small, D M

    1976-01-01

    Since chlorpromazine hydrochloride [2-chloro-10-(3-dimethylaminopropyl)-phenothiazine hydrochloride] is commonly implicated in causing bile-secretory failure in man and is secreted into bile, we have studied the physicochemical interactions of the drug with the major components of bile in vitro. Chlorpromazine hydrochloride molecules are amphiphilic by virtue of possessing a polar tertiary amine group linked by a short paraffin chain to a tricyclic hydrophobic part. At pH values below the apparent pK (pK'a 7.4) the molecules are water-soluble cationic detergents. We show that bile salts in concentrations above their critical micellar concentrations are precipitated from solution by chlorpromazine hydrochloride as insoluble 1:1 salt complexes. In the case of mixed bile-salt/phosphatidylcholine micellar solutions, however, the degree of precipitation is inhibited by the phospholipid in proportion to its mole fraction. With increases in the concentration of chlorpromazine hydrochloride or bile salt, micellar solubilization of the precipitated complexes results. Sonicated dispersions of the negatively charged phospholipid phosphatidylserine were also precipitated, but dispersions of the zwitterionic phospholipid phosphatidylcholine were not. Chlorpromazine hydrochloride efficiently solubilized these membrane phospholipids as mixed micellar solutions when the drug:phospholipid molar ratio reached 4:1. Polarizing-microscopy and X-ray-diffraction studies revealed that the precipitated complexes were amorphous and potentiometric studies confirmed the presence of a salt bond. Some dissociation of the complex occurred in the case of the most polar bile salt (Ks 0.365). As canalicular bile-salt secretion determines much of bile-water flow, we propose that complexing and precipitation of bile salts by chlorpromazine hydrochloride and its metabolites may be physicochemically related to the reversible bile-secretory failure produced by this drug. Images PLATE 1 PLATE 2 PMID

  3. Role of Decompression in Late Presentation of Cervical Spinal Cord Disorders

    PubMed Central

    Sakale, Harshal; Dulani, Rajesh; Singh, Pradeep K; Sanrakhia, Manoj

    2014-01-01

    Study Design Prospective study conducted at Jawaharlal Nehru Medical College, Datta Meghe Institute of Medical Sciences, Wardha, India. Purpose To show the efficacy of decompression in the late presentation of cervical spinal cord disorders. Overview of Literature Studies by various authors have shown that early spinal decompression results in better neurological outcomes. Methods From January 2003 to January 2005, 11 of the 41 patients with cervical spinal cord compression, meeting the inclusion criteria, underwent anterior decompression; interbody graft placement and stabilization by anterior cervical locking plate. The neurologic and functional outcomes were recorded. Results Five patients had spinal cord injury and 6 patients had compressive cervical myelopathy. Complications included 1 death and 1 plate loosening. No patient lost their preoperative neurological status. One patient had no improvement, 2 patients showed full recovery. The mean follow-up is 28.3 month. At the of rehabilitation, 6 were able to walk without support), 2 could walk with support, and 1 needed a wheelchair. The average American Spinal Injury Association motor score on admission to the hospital, 32.8 (standard deviation [SD], 30.5); admission to rehabilitation, 38.6 (SD, 32.4); discharge from rehabilitation, 46.2 (SD, 33.7). The most recent follow-up was 64.0 (SD, 35.3). Conclusions The anterior approach for cervical decompression allows for adequate decompression. This decompression is the best chance offered in even late reported cases, including posttraumatic cases where there is no evidence of cord transactions. The use of anterior cervical plates reduces the chances of graft loosening, extruding, or collapsing. PMID:24761201

  4. Circular-dichroism and electron-microscopy studies of human subcomponent C1q before and after limited proteolysis by pepsin.

    PubMed Central

    Brodsky-Doyle, B; Leonard, K R; Reid, K B

    1976-01-01

    1. A fragment of human subcomponent C1q was prepared by limited proteolysis with pepsin at 37 degrees C for 20 h, and at pH4.4, followed by gel filtration on Sephadex G-200. This fragment was shown to contain all the collagen-like features known to be present in the intact molecule [Reid (1976) Biochem. J. 155, 5-17]. 2. Circular-dichroism studies showed the presence of positive bands at 230 and 223 nm in the intact subcomponent C1q and pepsin fragment respectively, compared with a positive band at 220 nm obtained for lathyritic rat skin collagen. These bands were abolished by collagenase treatment, which suggested that there may some collagen-like triple-helical structure in subcomponent C1q and that this structure resides in the pepsin-resistant portion of the molecule. However, the 230 and 223 nm bands had a substantially lower magnitude than that obtained for the unaggregated single fibres of totally triple-helical collagen. 3. Thermal-transition temperatures obtained for subcomponent C1q, the pepsin fragment and the reduced and alkylated pepsin fragment were 48 degrees, 48 degrees and 39 degrees C respectively, compared with a value of 38 degrees C obtained for lathyritic rat skin collagen. 4. Only the unreduced pepsin fragment regained significant amounts (up to 60%) of collagen-like structure, after heat denaturation and cooling, as estimated by circular-dichroism measurements. 5. Electron-microscopy studies of subcomponent C1q and the collagen-like pepsin-resistant fragment of subcomponent C1q showed that the six peripheral globular regions of the molecule were fragmented by pepsin leaving the six collagen-like connecting strands and fibril-like central portion intact. Images PLATE 1 PLATE 2 PMID:187173

  5. Current plate velocities relative to the hotspots incorporating the NUVEL-1 global plate motion model

    SciTech Connect

    Gripp, A.E.; Gordon, R.G. )

    1990-07-01

    NUVEL-1 is a new global model of current relative plate velocities which differ significantly from those of prior models. Here the authors incorporate NUVEL-1 into HS2-NUVEL1, a new global model of plate velocities relative to the hotspots. HS2-NUVEL1 was determined from the hotspot data and errors used by Minster and Jordan (1978) to determine AM1-2, which is their model of plate velocities relative to the hotspots. AM1-2 is consistent with Minster and Jordan's relative plate velocity model RM2. Here the authors compare HS2-NUVEL1 with AM1-2 and examine how their differences relate to differences between NUVEL-1 and RM2. HS2-NUVEL1 plate velocities relative to the hotspots are mainly similar to those of AM1-2. Minor differences between the two models include the following: (1) in HS2-NUVEL1 the speed of the partly continental, apparently non-subducting Indian plate is greater than that of the purely oceanic, subducting Nazca plate; (2) in places the direction of motion of the African, Antarctic, Arabian, Australian, Caribbean, Cocos, Eurasian, North American, and South American plates differs between models by more than 10{degree}; (3) in places the speed of the Australian, Caribbean, Cocos, Indian, and Nazca plates differs between models by more than 8 mm/yr. Although 27 of the 30 RM2 Euler vectors differ with 95% confidence from those of NUVEL-1, only the AM1-2 Arabia-hotspot and India-hotspot Euler vectors differ with 95% confidence from those of HS2-NUVEL1. Thus, substituting NUVEL-1 for RM2 in the inversion for plate velocities relative to the hotspots changes few Euler vectors significantly, presumably because the uncertainty in the velocity of a plate relative to the hotspots is much greater than the uncertainty in its velocity relative to other plates.

  6. Cellular synthesis and axonal transport of gamma-aminobutyric acid in a photoreceptor cell of the barnacle.

    PubMed Central

    Koike, H; Tsuda, K

    1980-01-01

    1. [3H]glutamate or [3H]gamma-aminobutyric acid (GABA) was injected into the photoreceptor cell of the lateral ocellus of Balanus eburneus, in order to study the transmitter substance of the cell. 2. The photoreceptor cell synthesized [3H]GABA from injected [3H]glutamate. 3. The newly formed [3H]GABA moved inside the photoreceptor axon towards the axon terminal with a velocity of about 0.9 mm/hr. Injected [3H]GABA moved at 0.9 mm/hr and also at 0.4 mm/hr. 4. Axonally transported [3H]GABA reached the axon terminal within several hours following the injection. It did not accumulate at the terminal, but gradually disappeared. 5. Light-microscope and electron-microscope autoradiography following the injection of [3H]GABA revealed that [3H]-reacted silver grains were present in a certain type of axon terminal. The terminal thus identified as that of a photoreceptor cell contains many clear, polymorphic synaptic vesicles about 300-500 A in diameter, some dense-cored vesicles 700-1300 A in diameter, and glycogen granules. The terminal forms many synapses, and each synapse has a synaptic dense body. The terminal always faces two post-synaptic elements at the synapse, forming a triad with a gap distance of about 160-200 A. 6. A GABA analogue, [3H]di-aminobutyric acid, was selectively taken up into the terminals previously identified as those of photoreceptors. 7. These results support the notion that the transmitter substance of the photoreceptor cell of the barnacle is GABA. Images Plate 1 Plate 2 PMID:6160239

  7. Different osteosyntheses for Colles' fracture

    PubMed Central

    Gjerdet, Nils R; Lundberg, Odd J; Lilleng, Peer K; Hove, Leiv M

    2009-01-01

    Background and purpose In recent years several different plate designs for internal fixation of fractures of the distal radius have been developed. However, few biomechanical studies have been performed to compare these new implants. The purpose of this study was to compare the mechanical properties of 5 different commercially available plates (3 volar and 2 dorsal) with standard K-wire fixation using a distal radial cadaver model. Material and methods 42 human radial bones from 26 cadavers were included. The bone mineral density (BMD) was measured by DEXA in all bones, and the radial bones were assigned to 6 equiv alent groups based on bone density and total amount of mineral. A distal radial osteotomy was done and a dorsal 30-degree wedge of bone was removed. 1 K-wire fixation group and 5 plate groups were tested for rigidity, yield load, and maximum load. Results When data from dorsally and volarly applied plates were pooled, we did not find any statistically significant differences between them regarding stiffness, yield load, and maximum load. The K-wire group showed significantly lower yield load than 3 of the plate groups. There were no statistically significant differences in yield load between the 5 plate groups. The K-wire group showed lower rigidity than the plate groups. The K-wire group and 1 plate group failed at a statistically significant lower maximum load than the 4 other plate groups. Interpretation The volar plates had the same mechanical stability as the dorsally applied plates, and they are therefore a good alternative to dorsally applied plates. K-wire osteosynthesis was inferior to plate osteosyntheses regarding all mechanical properties. PMID:19404810

  8. Analysis of the irradiation data for A302B and A533B correlation monitor materials

    SciTech Connect

    Wang, J.A.

    1996-04-01

    The results of Charpy V-notch impact tests for A302B and A533B-1 Correlation Monitor Materials (CMM) listed in the surveillance power reactor data base (PR-EDB) and material test reactor data base (TR-EDB) are analyzed. The shift of the transition temperature at 30 ft-lb (T{sub 30}) is considered as the primary measure of radiation embrittlement in this report. The hyperbolic tangent fitting model and uncertainty of the fitting parameters for Charpy impact tests are presented in this report. For the surveillance CMM data, the transition temperature shifts at 30 ft-lb ({Delta}T{sub 30}) generally follow the predictions provided by Revision 2 of Regulatory Guide 1.99 (R.G. 1.99). Difference in capsule temperatures is a likely explanation for large deviations from R.G. 1.99 predictions. Deviations from the R.G. 1.99 predictions are correlated to similar deviations for the accompanying materials in the same capsules, but large random fluctuations prevent precise quantitative determination. Significant scatter is noted in the surveillance data, some of which may be attributed to variations from one specimen set to another, or inherent in Charpy V-notch testing. The major contributions to the uncertainty of the R.G. 1.99 prediction model, and the overall data scatter are from mechanical test results, chemical analysis, irradiation environments, fluence evaluation, and inhomogeneous material properties. Thus in order to improve the prediction model, control of the above-mentioned error sources needs to be improved. In general the embrittlement behavior of both the A302B and A533B-1 plate materials is similar. There is evidence for a fluence-rate effect in the CMM data irradiated in test reactors; thus its implication on power reactor surveillance programs deserves special attention.

  9. Rabbit β-glucuronidase. Purification and properties, and the existence of multiple forms

    PubMed Central

    Dean, Roger T.

    1974-01-01

    1. β-Glucuronidase (EC 3.2.1.31) was purified from rabbit liver by a procedure involving autolysis, (NH4)2SO4 fractionation, chromatography on DEAE-cellulose and hydroxyapatite, gel filtration, sedimentation in a sucrose gradient, and isoelectric focusing. 2. Electron microscopy revealed ferritin as the major contaminant in later stages of purification and also showed aggregates of enzyme molecules. Particular attention was paid to the removal of ferritin. 3. The purified enzyme was homogeneous in polyacrylamide-gel electrophoresis both in non-dissociating conditions and in the presence of sodium dodecyl sulphate, and in Ouchterlony gel diffusion and immunoelectrophoresis against polyspecific antisera. 4. Sedimentation in sucrose gradients gave a molecular weight of 300000, whereas gel filtration indicated 440000. 5. Subunits of 75000 molecular weight were observed in gel electrophoresis in the presence of sodium dodecyl sulphate and in gel filtration in the presence of urea. 6. The Km value for p-nitrophenyl β-d-glucuronide was 0.6mm, and the enzyme was extremely sensitive to lactone inhibitors. It was also inhibited by Hg2+ ions. 7. Multiple forms were observed in the pure enzyme by isoelectric focusing, with pI values of 4.5–5.8. Subunits showed similar heterogeneity. The origin of the multiple forms was investigated in detail, and the possibility of artifact generation largely excluded. Some of the forms of lowest pI disappeared after neuraminidase digestion. The nature of the residual heterogeneity remains to be elucidated. ImagesPLATE 1PLATE 2 PMID:4215418

  10. Properties of a 5′-nucleotidase purified from mouse liver plasma membranes

    PubMed Central

    Evans, W. H.; Gurd, James W.

    1973-01-01

    1. Extraction of a mouse liver plasma-membrane fraction with a detergent buffer, N-dodecylsarcosinate–Tris buffer (sarcosyl–Tris buffer), solubilized 90% of the protein and 70% of the 5′-nucleotidase activity. 2. The proteins of the sarcosyl–Tris buffer extract were fractionated by a rate-zonal centrifugation in a sucrose–detergent gradient. The major protein peak sedimented ahead of phospholipids, which mainly remained in the overlay. Glycoproteins were separated ahead of the protein peak. 3. The 5′-nucleotidase activity peak was associated with 5% of the protein applied to the gradient, and contained relatively few protein bands. 4. The 5′-nucleotidase was purified further by gel filtration on Sepharose and Sephadex columns equilibrated with sarcosyl–Tris buffer, to give a single glycoprotein band on sodium dodecyl sulphate–polyacrylamide-gel electrophoresis. The purified enzyme was lipid-free. 5. Electrophoresis in polyacrylamide gels in sarcosyl–Tris buffers showed that the enzymic activity was coincident with the protein band. 6. The molecular weight suggested for the enzyme activity by gel filtration or centrifugation in sucrose gradients was 140000–150000. Sometimes, a minor enzyme peak of lower molecular weight was obtained. 7. Polyacrylamide-gel electrophoresis in sodium dodecyl sulphate indicated that as the polyacrylamide concentration was increased from 5 to 15%, the apparent molecular weight of the enzyme decreased from 130000 to 90000. 8. The evidence that 5′-nucleotidase is composed of two active and similar, if not identical, glycoprotein subunits and the role of detergent in effecting the separation of membrane proteins and glycoproteins are discussed. 9. Substrate requirements, pH optima and the nature of inhibition by an analogue of adenosine diphosphate are reported. ImagesPLATE 1PLATE 2Fig. 6. PMID:4721620

  11. Development of lava tubes in the light of observations at Mauna Ulu, Kilauea Volcano, Hawaii

    USGS Publications Warehouse

    Peterson, D.W.; Holcomb, R.T.; Tilling, R.I.; Christiansen, R.L.

    1994-01-01

    During the 1969-1974 Mauna Ulu eruption on Kilauea's upper east rift zone, lava tubes were observed to develop by four principal processes: (1) flat, rooted crusts grew across streams within confined channels; (2) overflows and spatter accreted to levees to build arched roofs across streams; (3) plates of solidified crust floating downstream coalesced to form a roof; and (4) pahoehoe lobes progressively extended, fed by networks of distributaries beneath a solidified crust. Still another tube-forming process operated when pahoehoe entered the ocean; large waves would abruptly chill a crust across the entire surface of a molten stream crossing through the surf zone. These littoral lava tubes formed abruptly, in contrast to subaerial tubes, which formed gradually. All tube-forming processes were favored by low to moderate volume-rates of flow for sustained periods of time. Tubes thereby became ubiquitous within the pahoehoe flows and distributed a very large proportionof the lava that was produced during this prolonged eruption. Tubes transport lava efficiently. Once formed, the roofs of tubes insulate the active streams within, allowing the lava to retain its fluidity for a longer time than if exposed directly to ambient air temperature. Thus the flows can travel greater distances and spread over wider areas. Even though supply rates during most of 1970-1974 were moderate, ranging from 1 to 5 m3/s, large tube systems conducted lava as far as the coast, 12-13 km distant, where they fed extensive pahoehoe fields on the coastal flats. Some flows entered the sea to build lava deltas and add new land to the island. The largest and most efficient tubes developed during periods of sustained extrusion, when new lava was being supplied at nearly constant rates. Tubes can play a major role in building volcanic edifices with gentle slopes because they can deliver a substantial fraction of lava erupted at low to moderate rates to sites far down the flank of a volcano. We

  12. The Nature of the Distinctive Microscopic Features in R5(SixGe1-x)4 Magnetic Refrigeration Materials

    SciTech Connect

    Ozan Ugurlu

    2006-05-01

    . Both observations are consistent with the stated hypothesis that the growth direction of the thin-plates is parallel to an invariant line direction. Based on the terrace-ledge structure of the thin-plate interface a displacive-diffusional growth mechanism has been proposed to explain the rapid formation of the R{sub 5}(Si{sub x},Ge{sub 1-x}){sub 3} plates.

  13. Dielectric Barrier Discharges in Helium at Atmospheric Pressure: Experiments and Model in the Needle-Plane Geometry

    NASA Astrophysics Data System (ADS)

    Radu, Ion; Bartnikas, Raymond; Wertheimer, Michael

    2002-10-01

    We present an experimental and theoretical modeling study of "dielectric barrier discharges" (DBD) at atmospheric pressure in a needle-plane configuration. Synchronous, Ultra High Speed Imaging (UHSI, using a Princeton Instruments PI-MAX 512RB Digital ICCD Camera System) and real-time dual detection (optical-electrical) diagnostics have been carried out in a flow of He. A phase-resolved synchronizing circuit was used to trigger the ICCD camera's shutter for durations varying from 2 ns up to 100 ms. All diagnostics, including the PI-MAX images, could be precisely synchronized and processed on a PC computer. The high voltage electrode was a steel needle with a sharp point of precisely-machined radius, while a thin (1.6 mm) ceramic (Al2O3) plate with a metallized bottom surface was used as the ground electrode. Three different situations have been studied, namely (i) the bare Al2O3, and with an ultra-thin coatings of (ii) graphite (a semiconductor) or (iii) metal, the latter two at floating potential. The purpose of these experiments was to investigate possible effects of surface charging on the discharge behavior [1]. The axial [y(t)] and radial [x(t)] time evolutions of the discharge have been measured by UHSI, plotted, and found to differ very significantly among cases (i) to (iii). In the needle-plane configuration (like in the plane-plane case), the DBD is characterized by a single pulse per half-period of the applied voltage. A two-dimensional model of the needle-plane discharge, based upon the continuity equations for electrons, ions, excited particles, and the Poisson equation, is developed; it assumes a low degree of ionization, so that the transport coefficients of the gas are uniquely determined by the local electric field [2]. In order to determine the electric field and the electrical potential in the (hyperboloidal) needle-plane geometry, the finite element method is used. We have found excellent agreement between measured and calculated [y(t)] and [x

  14. Connexions from large, ipsilateral hind limb muscle and skin afferents to the rostral main cuneate nucleus and to the nucleus X region in the cat.

    PubMed Central

    Johansson, H; Silfvenius, H

    1977-01-01

    the cerebellum, and three were synapitcally activated by axon-collaterals of an undefined non-segmental cell. 5. Two DV-X cells which were activated by cutaneous afferents possibly had their spinal fibres deep in the dorsal column. Both were activated from the cerebellum, one by collaterals of a spinal axon. The functional organization of the three juxtaposed medullary nuclei, Z, rMCN and DV-X is discussed. Images Plate 3 Plates 1 and 2 (cont.) Plates 1 and 2 PMID:850200

  15. Empirical Tsunami Hazard Assessment of Near-Field Plate-Boundary and Crustal Fault Sources Demonstrated for the Pacific Coast of Canada

    NASA Astrophysics Data System (ADS)

    Leonard, L. J.; Rogers, G. C.

    2015-12-01

    We demonstrate an empirical method for preliminary tsunami hazard assessment of near-field fault sources that lack long historic records, paleoseismic/paleotsunami data and/or adequate tsunami modelling studies. Along the Pacific coast of Canada, the North America plate boundary is characterized by varying degrees of convergence with adjacent oceanic plates and microplates. The 1700 M~9 Cascadia earthquake ruptured at least the full extent of Juan de Fuca plate subduction as far north as central Vancouver Island; paleoseismic data show that similar events have occurred approximately every 500 years throughout the Holocene, accompanied by large tsunamis. Further north along the margin, the paleoseismic and paleotsunami histories of the Explorer, Winona, and Haida Gwaii segments of the margin are unknown. The Explorer plate is subducting beneath Vancouver Island at about half the rate of the Juan de Fuca plate; this locked segment may rupture independently or it may slip concurrently with the rest of the Cascadia subduction zone system to the south. The tsunamigenic potential of the Winona segment off northern Vancouver Island is poorly understood. The occurrence of the 2012 M7.8 thrust earthquake off southern Haida Gwaii confirmed the tsunamigenic nature of partitioned convergent slip on this dominantly transform margin segment. Parts of the coastline face additional tsunami hazard from submarine crustal faults. For potentially tsunamigenic faults with unknown history, we use (1) geophysical data to constrain fault rupture area, (2) empirical relations to estimate earthquake magnitude from the rupture area, (3) plate motion models and geodetic data to constrain convergence and thrust earthquake recurrence rates, and (4) empirical relations to estimate near-field tsunami runup at coastal sites, given distance from the rupture. The success of this approach is demonstrated by general agreement between expected and observed earthquake magnitude and near-field tsunami

  16. Interseismic coupling and seismic potential along the Central Andes subduction zone

    NASA Astrophysics Data System (ADS)

    Chlieh, Mohamed; Perfettini, Hugo; Tavera, Hernando; Avouac, Jean-Philippe; Remy, Dominique; Nocquet, Jean-Mathieu; Rolandone, FréDéRique; Bondoux, Francis; Gabalda, Germinal; Bonvalot, Sylvain

    2011-12-01

    We use about two decades of geodetic measurements to characterize interseismic strain build up along the Central Andes subduction zone from Lima, Peru, to Antofagasta, Chile. These measurements are modeled assuming a 3-plate model (Nazca, Andean sliver and South America Craton) and spatially varying interseismic coupling (ISC) on the Nazca megathrust interface. We also determine slip models of the 1996 Mw = 7.7 Nazca, the 2001 Mw = 8.4 Arequipa, the 2007 Mw = 8.0 Pisco and the Mw = 7.7 Tocopilla earthquakes. We find that the data require a highly heterogeneous ISC pattern and that, overall, areas with large seismic slip coincide with areas which remain locked in the interseismic period (with high ISC). Offshore Lima where the ISC is high, a Mw˜8.6-8.8 earthquake occurred in 1746. This area ruptured again in a sequence of four Mw˜8.0 earthquakes in 1940, 1966, 1974 and 2007 but these events released only a small fraction of the elastic strain which has built up since 1746 so that enough elastic strain might be available there to generate a Mw > 8.5 earthquake. The region where the Nazca ridge subducts appears to be mostly creeping aseismically in the interseismic period (low ISC) and seems to act as a permanent barrier as no large earthquake ruptured through it in the last 500 years. In southern Peru, ISC is relatively high and the deficit of moment accumulated since the Mw˜8.8 earthquake of 1868 is equivalent to a magnitude Mw˜8.4 earthquake. Two asperities separated by a subtle aseismic creeping patch are revealed there. This aseismic patch may arrest some rupture as happened during the 2001 Arequipa earthquake, but the larger earthquakes of 1604 and 1868 were able to rupture through it. In northern Chile, ISC is very high and the rupture of the 2007 Tocopilla earthquake has released only 4% of the elastic strain that has accumulated since 1877. The deficit of moment which has accumulated there is equivalent to a magnitude Mw˜8.7 earthquake. This study thus

  17. Viability and nematophagous activity of the freeze-dried fungus Arthrobotrys robusta against Ancylostoma spp. infective larvae in dogs.

    PubMed

    Carvalho, Rogério Oliva; Braga, Fabio Ribeiro; Araújo, Jackson Victor

    2011-03-10

    Viability and in vitro and in vivo activities of freeze-dried conidia of the predatory fungus Arthrobotrys robusta (I-31) were evaluated against infective larvae (L(3)) of Ancylostoma spp. in dogs. A. robusta conidia were lyophilized and stored at 4°C for a month. Freeze-dried conidia were diluted to 1×10(3)conidia/ml and tested in vivo. The treated group consisted of a solution containing conidia (1ml) and 1000 Ancylostoma spp. (L(3)) placed on Petri dishes plated with 2% water-agar (2% WA), at 25°C, in the dark for 10 days. The control group consisted of 1000 Ancylostoma spp. L(3), plated on 2% WA. After 10 days, Ancylostoma spp. L(3) from both the treated and the control groups were recovered and counted. The in vivo test was performed on two dogs by administering a single oral dose of freeze-dried conidia (1.5×10(5)) in aqueous solution to one animal and only water to the other. Fecal samples were collected at 12, 24 and 48h after the treatments, plated 2% WA plates and incubated at 25°C for 15 days. A thousand Ancylostoma spp. L(3) larvae were spread on these plates. At day 15, infective L(3) recovered from the treated and control groups were counted. In the in vitro test, A. robusta was able to survive the freeze-drying process, grow in the plates, form traps and capture Ancylostoma spp. L(3). There was a 75.38% decrease in the number of infective larvae recovered from the treated group. The in vivo test showed that freeze-dried A. robusta conidia survived the passage through the gastrointestinal tract of the treated dog, was able to grow in the plates and capture Ancylostoma spp. L(3), reducing the number of recovered L(3) (p<0.01). Freeze-drying can be an alternative method for conservation of conidia of nematophagous fungi. PMID:21111535

  18. Complete erasing of ghost images on computed radiography plates and role of deeply trapped electrons

    NASA Astrophysics Data System (ADS)

    Ohuchi-Yoshida, Hiroko; Kondo, Yasuhiro

    2011-12-01

    Computed radiography (CR) plates made of europium-doped Ba(Sr)FBr(I) were simultaneously exposed to filtered ultraviolet light and visible light in order to erase ghost images, i.e., latent image that is unerasable with visible light (LIunVL) and reappearing one, which are particularly observed in plates irradiated with a high dose and/or cumulatively over-irradiated. CR samples showing LIunVLs were prepared by irradiating three different types of CR plates (Agfa ADC MD10, Kodak Directview Mammo EHRM2, and Fuji ST-VI) with 50 kV X-ray beams in the dose range 8.1 mGy-8.0 Gy. After the sixth round of simultaneous 6 h exposures to filtered ultraviolet light and visible light, all the LIunVLs in the three types of CR plates were erased to the same level as in an unirradiated plate and no latent images reappeared after storage at 0 °C for 14 days. With conventional exposure to visible light, LIunVLs consistently remained in all types of CR plates irradiated with higher doses of X-rays and latent images reappeared in the Agfa M10 plates after storage at 0 °C. Electrons trapped in deep centers cause LIunVLs and they can be erased by simultaneous exposures to filtered ultraviolet light and visible light. To study electrons in deep centers, the absorption spectra were examined in all types of irradiated CR plates by using polychromatic ultraviolet light from a deep-ultraviolet lamp. It was found that deep centers showed a dominant peak in the absorption spectra at around 324 nm for the Agfa M10 and Kodak EHRM2 plates, and at around 320 nm for the Fuji ST-VI plate, in each case followed by a few small peaks. The peak heights were dose-dependent for all types of CR samples, suggesting that the number of electrons trapped in deep centers increases with the irradiation dose.

  19. Revisiting the properties of delafossite CuCrO{sub 2}: A single crystal study

    SciTech Connect

    Poienar, Maria; Hardy, Vincent; Kundys, Bohdan; Singh, Kiran; Maignan, Antoine; Damay, Francoise; Martin, Christine

    2012-01-15

    Platelet-like single-crystals of delafossite CuCrO{sub 2} have been successfully grown and characterised by X-ray diffraction and pole figures, scanning electron and atomic force microscopy. Transport measurements reveal that the resistivity is highly anisotropic, with a ratio of about 35 at 300 K between the in- and out-of-plane directions, reflecting the layered crystal structure. The magnetization and specific heat data show that CuCrO{sub 2} undergoes a unique antiferromagnetic transition at T{sub N}=24.0 K, in contrast to a recent report on CuCrO{sub 2} single-crystals showing the existence of two magnetic transitions, T{sub N1}=24.2 K and T{sub N2}=23.6 K, depending on the orientation of the applied magnetic field along and perpendicular to c, respectively. - Graphical abstract: 3R-CuCrO{sub 2} platelet-like single crystals have been successfully grown by the flux method. As revealed by {chi}(T) and C(T) measurements, their properties are characterised by a unique antiferromagnetic transition at T{sub N}=24 K. Interestingly, despite a very small magnetic anisotropy, a large one is evidenced by the resistivity ratio, {rho}{sub c}/{rho}{sub ab}{approx}35, at 300 K. This suggests an easier charge hopping in the [CrO{sub 2}] planes rather than along (Cr-O-Cu) pathways, i.e. along c axis. Highlights: Black-Right-Pointing-Pointer R-CuCrO{sub 2} plate-like single crystals have been synthesised by the flux method. Black-Right-Pointing-Pointer Growth takes place layer-by-layer and some growth defects have been observed. Black-Right-Pointing-Pointer CuCrO{sub 2} single crystals exhibit a unique antiferromagnetic transition at T{sub N}=24 K. Black-Right-Pointing-Pointer Transport measurements reveal that the resistivity is highly anisotropic.

  20. Comparison of the Mechanical Characteristics of a Universal Small Biplane Plating Technique Without Compression Screw and Single Anatomic Plate With Compression Screw.

    PubMed

    Dayton, Paul; Ferguson, Joe; Hatch, Daniel; Santrock, Robert; Scanlan, Sean; Smith, Bret

    2016-01-01

    To better understand the mechanical characteristics of biplane locked plating in small bone fixation, the present study compared the stability under cyclic cantilever loading of a 2-plate locked biplane (BPP) construct without interfragmentary compression with that of a single-plate locked construct with an additional interfragmentary screw (SPS) using surrogate bone models simulating Lapidus arthrodesis. In static ultimate plantar bending, the BPP construct failed at significantly greater load than did the SPS construct (556.2 ± 37.1 N versus 241.6 ± 6.3 N, p = .007). For cyclic failure testing in plantar bending at a 180-N starting load, the BPP construct failed at a significantly greater number of cycles (158,322 ± 50,609 versus 13,718 ± 10,471 cycles) and failure load (242.5 ± 25.0 N versus 180.0 ± 0.0 N) than the SPS construct (p = .002). For cyclic failure testing in plantar bending at a 120-N starting load, the results were not significantly different between the BPP and SPS constructs for the number of cycles (207,646 ± 45,253 versus 159,334 ± 69,430) or failure load (205.0 ± 22.4 N versus 185.0 ± 33.5 N; p = .300). For cyclic testing with 90° offset loading (i.e., medial to lateral bending) at a 120-N starting load, all 5 BPP constructs (tension side) and 2 of the 5 SPS constructs reached 250,000 cycles without failure. Overall, the present study found the BPP construct to have superior or equivalent stability in multiplanar orientations of force application in both static and fatigue testing. Thus, the concept of biplane locked plating, using 2 low profile plates and unicortical screw insertion, shows promise in small bone fixation, because it provides consistent stability in multiplanar orientations, making it universally adaptable to many clinical situations. PMID:26872521

  1. Solar CIV Vacuum-Ultraviolet Fabry-Perot Interferometers

    NASA Technical Reports Server (NTRS)

    Gary, G. Allen; West, Edward A.; Rees, David; McKay, Jack A.; Zukic, Maumer; Herman, Peter

    2006-01-01

    Aims: A tunable, high spectral resolution, high effective finesse, vacuum ultraviolet (VUV) Fabry-Perot interferometer (PPI) is designed for obtaining narrow-passband images, magnetograms, and Dopplergrams of the transition region emission line of CIV (155 nm). Methods: The integral part of the CIV narrow passband filter package (with a 2-10 pm FWHM) consists of a multiple etalon system composed of a tunable interferometer that provides high-spectral resolution and a static low-spectral resolution interferometer that allows a large effective free spectral range. The prefilter for the interferometers is provided by a set of four mirrors with dielectric high-reflective coatings. A tunable interferometer, a VUV piezoelectric-control etalon, has undergone testing using the surrogate F2 eximer laser line at 157 nm for the CIV line. We present the results of the tests with a description of the overall concept for a complete narrow-band CIV spectral filter. The static interferometer of the filter is envisioned as being hudt using a set of fixed MgF2 plates. The four-mirror prefilter is designed to have dielectric multilayer n-stacks employing the design concept used in the Ultraviolet Imager of NASA's Polar Spacecraft. A dual etalon system allows the effective free spectral range to be commensurate with the prefilter profile. With an additional etalon, a triple etalon system would allow a spectrographic resolution of 2 pm. The basic strategy has been to combine the expertise of spaceflight etalon manufacturing with VUV coating technology to build a VUV FPI which combines the best attributes of imagers and spectrographs into a single compact instrument. Results. Spectro-polarimetry observations of the transition region CIV emission can be performed to increase the understanding of the magnetic forces, mass motion, evolution, and energy release within the solar atmosphere at the base of the corona where most of the magnetic field is approximately force-free. The 2D imaging

  2. Rigidity and definition of Caribbean plate motion from COCONet and campaign GPS observations

    NASA Astrophysics Data System (ADS)

    Mattioli, Glen; Miller, Jamie; DeMets, Charles; Jansma, Pamela

    2014-05-01

    The currently accepted kinematic model of the Caribbean plate presented by DeMets et al. (2007) is based on velocities from 6 continuous and 14 campaign GPS sites. COCONet is a multi-hazard GPS-Met observatory, which extends the existing infrastructure of the Plate Boundary Observatory in North America into the Caribbean basin. In 2010, UNAVCO in collaboration with UCAR, was funded by NSF to design, build, and initially maintain a network of 50 new cGPS/Met sites and include data from another 50 existing sites in the Caribbean region. The current COCONet siting plan calls for 46 new stations, 21 refurbished stations, and 77 existing stations across 26 nations in the Caribbean region. Data from all COCONet sites flow into the UNAVCO archive and are processed by the PBO analysis centers and are also processed independently by the UTA Geodesy Lab using GIPSY-OASISII (v.6.2) using an absolute point positioning strategy and final, precise orbits, clocks, and Earth orientation parameters from JPL in the IGS08 frame. We present here our refined estimate of Caribbean plate motion by evaluating data from an expanded number of stations with an improved spatial distribution. In order to better constrain the eastern margin of the plate near the Lesser Antilles subduction interface, campaign GPS observations have been collected on the island of Dominica over the last decade. These are combined with additional campaign observations from the western Caribbean, specifically from Honduras and Nicaragua. We have analyzed a total of 117 sites from the Caribbean region, including campaign data and the data from the cGPS stations that comprise COCONet. An updated velocity field for the Caribbean plate is presented and an inversion of the velocities for 24 sites yields a plate angular velocity that differs from previously published models. Our best fitting inversion to GPS velocities from these 24 sites suggests that 2-plate model for the Caribbean is required to fit the GPS

  3. Fundamental structure model of island arcs and subducted plates in and around Japan

    NASA Astrophysics Data System (ADS)

    Iwasaki, T.; Sato, H.; Ishiyama, T.; Shinohara, M.; Hashima, A.

    2015-12-01

    The eastern margin of the Asian continent is a well-known subduction zone, where the Pacific (PAC) and Philippine Sea (PHS) plates are being subducted. In this region, several island arcs (Kuril, Northeast Japan, Southwest Japan, Izu-Bonin and Ryukyu arcs) meet one another to form a very complicated tectonic environment. At 2014, we started to construct fundamental structure models for island arcs and subducted plates in and around Japan. Our research is composed of 6 items of (1) topography, (2) plate geometry, (3) fault models, (4) the Moho and brittle-ductile transition zone, (5) the lithosphere-asthenosphere boundary, and (6) petrological/rheological models. Such information is basic but inevitably important in qualitative understanding not only for short-term crustal activities in the subduction zone (particularly caused by megathrust earthquakes) but also for long-term cumulative deformation of the arcs as a result of strong plate-arc/arc-arc interactions. This paper is the first presentation of our research, mainly presenting the results of items (1) and (2). The area of our modelling is 12o-54o N and 118o-164o E to cover almost the entire part of Japanese Islands together with Kuril, Ryukyu and Izu-Bonin trenches. The topography model was constructed from the 500-m mesh data provided from GSJ, JODC, GINA and Alaska University. Plate geometry models are being constructed through the two steps. In the first step, we modelled very smooth plate boundaries of the Pacific and Philippine Sea plates in our whole model area using 42,000 earthquake data from JMA, USGS and ISC. For 7,800 cross sections taken with several directions to the trench axes, 2D plate boundaries were defined by fitting to the earthquake distribution (the Wadati-Benioff zone), from which we obtained equi-depth points of the plate boundary. These equi-depth points were then approximated by spline interpolation technique to eliminate shorter wave length undulation (<50-100 km). The obtained

  4. X-ray natural birefringence in reflection from graphene

    NASA Astrophysics Data System (ADS)

    Jansing, C.; Mertins, H.-Ch.; Gilbert, M.; Wahab, H.; Timmers, H.; Choi, S.-H.; Gaupp, A.; Krivenkov, M.; Varykhalov, A.; Rader, O.; Legut, D.; Oppeneer, P. M.

    2016-07-01

    , graphene materials have a potential to be used as tunable x-ray phase shifting λ /4 or λ /2 plates in the design of future high-intensity light sources.

  5. Identification of N-terminal methionine in the precursor of immunoglobulin light chain. Initiation of translation of messenger ribonucleic acid in plants and animals.

    PubMed Central

    Schechter, I; Burstein, Y

    1976-01-01

    The proteins programmed in the wheat-germ cell-free system by the mRNA coding for the MOPC-321 mouse myeloma L (light) chain were labelled with [35S]methionine, [4,5-3H]leucine or [3-3H]serine, and were subjected to amino acid-sequence analyses. Over 95% of the total cell-free product was sequenced as one homogeneous protein, which corresponds to the precursor of the L-chain protein. In the precursor, 20 amino acid residues precede the N-terminus of the mature protein. This extra piece contains one methionine residue at the N-terminus, one serine residue at position 18, and six leucine residues, which are clustered in two triplets at positions 6, 7, 8 and 11, 12, 13. The identification of methionine at the N-terminus of the precursor is in agreement with the evidence showing that unblocked methionine is the initiator residue for protein synthesis in eukaryotes. The absence of methionine at position 20, which precedes the N-terminal residue of the mature protein, suggests that myeloma cells synthesize the precursor. However, within the cell the precursor should be rapidly processed to the mature L chain, since precursor molecules have not yet been found in the intact animal. The abundance (30%) of leucine residues indicates that the extra-piece moiety is quite hydrophobic. The extra piece of the MOPC-321 L-chain precursor synthesized with the aid of the Krebs II ascites cell-free system is of identical size and it has the same leucine sequence [Schechter et al. (1975) Science 188, 160-162]. This indicates that cell-free systems derived from the plant and animal kingdom initiate mRNA translation from the same point. It is shown that the amino acid sequence of minute amounts of a highly labelled protein (0.1 pmol) can be faithfully determined in the presence of a large excess (over 2000 000-fold) of unrelated non-radioactive proteins. Images PLATE 2 PLATE 1 PMID:821467

  6. Rigidity and definition of Caribbean plate motion from COCONet and campaign GPS observations

    NASA Astrophysics Data System (ADS)

    Mattioli, G. S.; Miller, J. A.; DeMets, C.; Jansma, P. E.

    2015-12-01

    The kinematic model of the Caribbean plate presented by DeMets et al. (2007) is based on velocities from 6 continuous and 14 campaign GPS sites. COCONet is a multi-hazard GPS-Met observatory, which extends the existing infrastructure of the PBO in North America into the Caribbean basin. In 2010, UNAVCO in collaboration with UCAR, was funded by NSF to design, build, and initially maintain a network of 50 new cGPS/Met sites and include data from another 50 existing sites in the Caribbean region. The COCONet siting plan is for 46 new stations, 21 refurbished stations, and 77 existing stations across 26 nations in the Caribbean region. Data from all COCONet sites flow into the UNAVCO archive and are processed by the PBO analysis centers and are also processed independently by the UTA Geodesy Lab using GIPSY-OASISII (v.6.3) using an APP strategy and final, precise orbits, clocks, and EOP from JPL in the IGS08r frame. We present a refined estimate of Caribbean plate motion by evaluating data from an expanded number of stations with an improved spatial distribution. In order to better constrain the eastern margin of the plate near the Lesser Antilles subduction interface, campaign GPS observations have been collected on the island of Dominica over the last decade. These are combined with additional campaign observations from the western Caribbean, specifically from Honduras and Nicaragua. We have analyzed a total of 117 sites from the Caribbean region, including campaign data and the data from the cGPS stations that comprise COCONet. An updated velocity field for the Caribbean plate is presented and an inversion of the velocities for 24 sites yields a plate angular velocity that differs from previously published models. Our best fitting inversion to GPS velocities from these 24 sites suggests that 2-plate model for the Caribbean is required to fit the GPS observations, which implies that the Caribbean is undergoing modest (1-3 mm/yr) deformation within its interior. Some

  7. A global outer-rise/outer-trench-slope (OR/OTS) earthquake study

    NASA Astrophysics Data System (ADS)

    Wartman, J. M.; Kita, S.; Kirby, S. H.; Choy, G. L.

    2009-12-01

    Using improved seismic, bathymetric, satellite gravity and other geophysical data, we investigated the seismicity patterns and focal mechanisms of earthquakes in oceanic lithosphere off the trenches of the world that are large enough to be well recorded at teleseismic distances. A number of prominent trends are apparent, some of which have been previously recognized based on more limited data [1], and some of which are largely new [2-5]: (1) The largest events and the highest seismicity rates tend to occur where Mesozoic incoming plates are subducting at high rates (e.g., those in the western Pacific and the Banda segment of Indonesia). The largest events are predominantly shallow normal faulting (SNF) earthquakes. Less common are reverse-faulting (RF) events that tend to be deeper and to be present along with SNF events where nearby seamounts, seamount chains and other volcanic features are subducting [Seno and Yamanaka, 1996]. Blooms of SNF OR/OTS events usually occur just after and seaward of great interplate thrust (IPT) earthquakes but are far less common after smaller IPT events. (2) Plates subducting at slow rates (<20 mm/a) often show sparse OR/OTS seismicity. It is unclear if such low activity is a long-term feature of these systems or is a consequence of the long return times of great IPT earthquakes (e.g., the sparse OR/OTS seismicity before the 26 December 2004 M9.2 Sumatra earthquake and many subsequent OR/OTS events). (3) OR/OTS shocks are generally sparse or absent where incoming plates are very young (<20 Ma) (e.g., Cascadia, southern Mexico, Nankai, and South Shetlands). (4) Subducting plates of intermediate age (20 to about 65 Ma) display a diversity of focal mechanisms and seismicity patterns. In the Philippines, NE Indonesia, and Melanesia, bands of reverse faulting events occur at or near the trench and SNF earthquakes are restricted to OR/OTS sites further from the trench. (5) Clustering of OR/OTS events of all types commonly occurs where

  8. Experimental simulation of organic matter alteration in carbonaceous chondrites under an in situ micro FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Kebukawa, Y.; Nakashima, S.; Saiki, K.; Zolensky, M. E.

    2007-12-01

    Carbonaceous chondrites contain organic matter up to a few weight percents, most of which consists of kerogen- like macromolecular material. Chondritic organic matter preserves signatures of various evolutional steps from presolar materials, through aqueous alteration and thermal metamorphism in the parent asteroid up to delivery to the Earth. The organic-mineral interactions during these processes are little known. We report here on the experimental simulation of organic matter alteration on carbonaceous chondrite parent body under micro FTIR spectroscopy with a heating stage. Leonardite humic acid (IHSS standard humic acid) and synthetic saponite or natural antigorite were used as the macromolecular organic matter and the matrix mineral. These powdered samples were dispersed by MilliQ water then dropped on a CaF2 plate and dried. They were heated in the heating stage from room temperature to 600 °C with a heating rate of 10 °C/min in air, Ar gas, and H2+CO2 gas mixture (mixing ratio 1:1). H2+CO2 gas mixture enables controls of not only oxygen fugacity but also water vapor fugacity, and aqueous processing on chondrite parent bodies can be partly simulated. IR spectra were collected at every 20 °C under the micro FTIR spectroscopy. Aliphatic C-H increased from room temperature to approximately 250 °C then decreased. Aromatic C-H increased from room temperature to around 400-450 °C then decreased. These aliphatic C-H decrease and aromatic C-H increase are faster in air than in Ar or H2+CO2. These CH changes of leonardite humic acid are slower with the presence of saponite. These results indicate that organic matter transformation might be prevented by the clay mineral (saponite). Some carbonaceous chondrite samples mixed with the organic material (leonardite humic acid) will also be investigated by the same way. These results will elucidate interactions of chondritic macromolecular organic matter with matrix minerals during parent body processes.

  9. Preliminary studies on the heat exchanger option for S-CO{sub 2} power conversion cycle coupled to water cooled SMR

    SciTech Connect

    Ahn, Y.; Lee, J.; Lee, J. I.

    2012-07-01

    For more than a half century, the steam Rankine cycle had been the major power conversion cycle for a nuclear power plant. However, as the interest on the next generation reactors grows, a variety of alternative power conversion systems have been studied. Among them, the S-CO{sub 2} cycle (Supercritical carbon dioxide Brayton cycle) is considered as a promising candidate due to several benefits such as 1) Relatively high thermal efficiency at relatively low turbine inlet temperature, 2) High efficiency with simple lay-out 3) Compactness of turbo-machineries. 4) Compactness of total cycle combined with PCHE (Printed Circuit Heat Exchanger). According to the conventional classification of heat exchangers (HE), there are three kind of HE, 1) Tubular HEs, 2) Plate-type HEs, 3) Extended surface HEs. So far, the researcher has mostly assumed PCHE type HE for the S-CO{sub 2} cycle due to its compactness with reasonably low pressure drop. However, PCHE is currently one of the most expensive components in the cycle, which can have a negative effect on the economics of the cycle. Therefore, an alternative for the HE should be seriously investigated. By comparing the operating condition (pressure and temperature) there are three kind of HE in the S-CO{sub 2} cycle, 1) IHX (Intermediate Heat exchanger) 2) Recuperator and 3) Pre-cooler. In each heat exchanger, hot side and cold side coolants are different, i.e. reactor coolant to S-CO{sub 2} (IHX), S-CO{sub 2} to S-CO{sub 2}(Recuperator), S-CO{sub 2} to water (Pre-cooler). By considering all the attributes mentioned above, all existing types of heat exchangers are compared to find a possible alternative to PCHE. The comparing factors are 1) Size(volume), 2) Cost. Plate fin type HEs are considered to be the most competitive heat exchanger regarding the size and the cost after some improvements on the design limit are made. (authors)

  10. Studies of electrochemical oxidation of Zircaloy nuclear reactor fuel cladding using time-of-flight-energy elastic recoil detection analysis

    NASA Astrophysics Data System (ADS)

    Whitlow, H. J.; Zhang, Y.; Wang, Y.; Winzell, T.; Simic, N.; Ahlberg, E.; Limbäck, M.; Wikmark, G.

    2000-03-01

    The trend towards increased fuel burn-up and higher operating temperatures in order to achieve more economic operation of nuclear power plants places demands on a better understanding of oxidative corrosion of Zircaloy (Zry) fuel rod cladding. As part of a programme to study these processes we have applied time-of-flight-energy elastic recoil detection (ToF-E ERD), electrochemical impedance measurements and scanning electron microscopy to quantitatively characterise thin-oxide films corresponding to the pre-transition oxidation regime. Oxide films of different nominal thickness in the 9-300 nm range were grown on a series of rolled Zr and Zry-2 plates by anodisation in dilute H 2SO 4 with applied voltages. The dielectric thickness of the oxide layer was determined from the electrochemical impedance measurements and the surface topography characterised by scanning electron microscopy. ToF-E ERD with a 60 MeV 127I 11+ ion beam was used to determine the oxygen content and chemical composition of the oxide layer. In the Zr samples, the oxygen content (O atom cm -2) that was determined by ERD was closely similar to the O content derived from impedance measurements from the dielectric film. The absolute agreement was well within the uncertainty associated with the stopping powers. Moreover, the measured composition of the thick oxide layers corresponded to ZrO 2 for the films thicker than 65 nm where the oxide layer was resolved in the ERD depth profile. Zry-2 samples exhibited a similar behaviour for small thickness ( ⩽130 nm) but had an enhanced O content at larger thicknesses that could be associated either with enhanced rough surface topography or porous oxide formation that was correlated with the presence of Second Phase Particles (SPP) in Zry-2. The concentration of SPP elements (Fe, Cr, Ni) in relation to Zr was the same in the outer 9×10 17 atom cm -2 of oxide as in the same thickness of metal. The results also revealed the presence of about 1 at.% 32S in the

  11. Geometric accommodation between the dimensions of erythrocytes and the calibre of heart and muscle capillaries in the rat.

    PubMed Central

    Canham, P B; Potter, R F; Woo, D

    1984-01-01

    measured were narrower than this limit. The data on erythrocytes and capillaries were compared for six rats. The limiting diameter for passage of erythrocytes was remarkably uniform for all six animals. Images Plate 2 Plate 1 PMID:6707973

  12. Multichannel microchip electrophoresis device fabricated in polycarbonate with an integrated contact conductivity sensor array.

    PubMed

    Shadpour, Hamed; Hupert, Mateusz L; Patterson, Donald; Liu, Changgeng; Galloway, Michelle; Stryjewski, Wieslaw; Goettert, Jost; Soper, Steven A

    2007-02-01

    A 16-channel microfluidic chip with an integrated contact conductivity sensor array is presented. The microfluidic network consisted of 16 separation channels that were hot-embossed into polycarbonate (PC) using a high-precision micromilled metal master. All channels were 40 microm deep and 60 microm wide with an effective separation length of 40 mm. A gold (Au) sensor array was lithographically patterned onto a PC cover plate and assembled to the fluidic chip via thermal bonding in such a way that a pair of Au microelectrodes (60 microm wide with a 5 microm spacing) was incorporated into each of the 16 channels and served as independent contact conductivity detectors. The spacing between the corresponding fluidic reservoirs for each separation channel was set to 9 mm, which allowed for loading samples and buffers to all 40 reservoirs situated on the microchip in only five pipetting steps using an 8-channel pipettor. A printed circuit board (PCB) with platinum (Pt) wires was used to distribute the electrophoresis high-voltage to all reservoirs situated on the fluidic chip. Another PCB was used for collecting the conductivity signals from the patterned Au microelectrodes. The device performance was evaluated using microchip capillary zone electrophoresis (mu-CZE) of amino acid, peptide, and protein mixtures as well as oligonucleotides that were separated via microchip capillary electrochromatography (mu-CEC). The separations were performed with an electric field (E) of 90 V/cm and were completed in less than 4 min in all cases. The conductivity detection was carried out using a bipolar pulse voltage waveform with a pulse amplitude of +/-0.6 V and a frequency of 6.0 kHz. The conductivity sensor array concentration limit of detection (SNR = 3) was determined to be 7.1 microM for alanine. The separation efficiency was found to be 6.4 x 10(4), 2.0 x 10(3), 4.8 x 10(3), and 3.4 x 10(2) plates for the mu-CEC of the oligonucleotides and mu-CZE of the amino acids, peptides

  13. The Chromospheric Lyman Alpha SpectroPolarimeter (CLASP)

    NASA Astrophysics Data System (ADS)

    Kobayashi, K.; Tsuneta, S.; Trujillo Bueno, J.; Cirtain, J. W.; Bando, T.; Kano, R.; Hara, H.; Fujimura, D.; Ueda, K.; Ishikawa, R.; Watanabe, H.; Ichimoto, K.; Sakao, T.; de Pontieu, B.; Carlsson, M.; Casini, R.

    2010-12-01

    Magnetic fields in the solar chromosphere play a key role in the energy transfer and dynamics of the solar atmosphere. Yet a direct observation of the chromospheric magnetic field remains one of the greatest challenges in solar physics. While some advances have been made for observing the Zeeman effect in strong chromospheric lines, the effect is small and difficult to detect outside sunspots. The Hanle effect offers a promising alternative; it is sensitive to weaker magnetic fields (e.g., 5-500 G for Ly-Alpha), and while its magnitude saturates at stronger magnetic fields, the linear polarization signals remain sensitive to the magnetic field orientation. The Hanle effect is not only limited to off-limb observations. Because the chromosphere is illuminated by an anisotropic radiation field, the Ly-Alpha line is predicted to show linear polarization for on-disk, near-limb regions, and magnetic field is predicted to cause a measurable depolarization. At disk center, the Ly-Alpha radiation is predicted to be negligible in the absence of magnetic field, and linearly polarized to an order of 0.3% in the presence of an inclined magnetic field. The proposed CLASP sounding rocket instrument is designed to detect 0.3% linear polarization of the Ly-Alpha line at 1.5 arcsecond spatial resolution (0.7’’ pixel size) and 10 pm spectral resolution. The instrument consists of a 30 cm aperture Cassegrain telescope and a dual-beam spectropolarimeter. The telescope employs a ``cold mirror’’ design that uses multilayer coatings to reflect only the target wavelength range into the spectropolarimeter. The polarization analyzer consists of a rotating waveplate and a polarizing beamsplitter that comprises MgF2 plates placed at Brewster’s Angle. Each output beam of the polarizing beamsplitter, representing two orthogonal linear polarizations, is dispersed and focused using a separate spherical varied-line-space grating, and imaged with a separate 512x512 CCD camera. Prototypes

  14. Sensing the Stable Boundary Layer in a Towing Tank

    NASA Astrophysics Data System (ADS)

    Steeneveld, G. J.; Dobrovolschi, D.; Paci, A.; Eiff, O.; Lacaze, L.; Holtslag, A. A. M.

    2010-09-01

    Understanding and forecasting the stable atmospheric boundary layer (SBL) over land is a challenge for already several decades. Generally, the SBL covers two different regimes. The first regime is the weakly SBL, characterised by well defined wind driven turbulence. The second regime covers the very SBL with weak turbulence, and then additional processes become relevant, such as meandering motions, gravity waves, drainage flows, intermittent turbulence and radiation divergence. Especially in this regime this complexity limits the understanding of the SBL and its representation in numerical weather prediction, climate models and air pollution models. For calm conditions, these models typically overestimate near surface temperature and wind speed, with adverse effects for understanding polar climate and end users in agriculture, transportation, and air quality assessment. To improve our understanding of the SBL, we study SBL turbulence in the CNRM-GAME stratified water flume in Toulouse. This unique facility, particularly well suited for stratified flow and BL studies, provides novel laboratory observations that extend earlier efforts of field observations and wind tunnel studies. Among other things, laboratory observations have the advantage of statistical robustness due to repeatability of the experiment and provide access to an extensive set of data. Hence, a 3x3 m2 plate covered with LEGO of Lx=1.57 cm and Ly=3.57 cm, (roughness length = 0.0014 m, and roughness density =0.250, index of frontal area = 0.125) was towed at different velocities through the tank of 22 x 3 x 1.6 m. In this way we were able to achieve an SBL of ~10 cm with bulk Richardson numbers in the range between 0.05 and 0.25, and turbulence with a well-behaved inertial subrange. We focus on the estimation of the non-dimensional velocity and density profiles, on higher order turbulent statistics (important for plume dispersion), as well as on the turbulence spectral behaviour. Finally, we aim to

  15. Major structural controls on the distribution of pre-Tertiary rocks, Nevada Test Site vicinity, southern Nevada

    SciTech Connect

    Cole, J.C.

    1998-10-23

    offset, most likely in the sinistral sense. Low-angle normal faults that are at least older than Oligocene, and may pre-date Late Cretaceous time are also present in the region. These faults are shown to locally displace blocks of pre-Tertiary rock by several kilometers. However, none of these structures can be traced for significant distances beyond its outcrop extent, and the inference is made that they do not exert regional influence on the distribution of pre-Tertiary rocks. The extensional strain accommodated by these low-angle normal faults appears to be local and highly irregular. 1 plate

  16. The formation and regression of synapses during the re-innervation of axolotl striated muscles.

    PubMed Central

    Bennett, M R; Raftos, J

    1977-01-01

    the same synaptic sites as those occupied by nerve 17. 6. In the subsequent sixteen weeks, the n value of synapses formed by nerve 17 declined whilst the n values of synapses formed by re-innervating nerve 16 on the same myofibres matured to their control size. 7. It is suggested that on severing nerve 16 collateral sprouting of nearby intact nerve 17 occurs and these collateral sprouts innervate the denervated synaptic sites, although the sprouts arenot as well matched to the denervated synaptic sites as are the original nerve terminals; thus if nerve 16 returns it preferentially forms synapses at its original synaptic sites, and the collateral synapses formed by nerve 17 regress. Images Plate 1 Plate 2 PMID:191597

  17. Studies on the Golgi apparatus. Cumulative inhibition of protein and glycoprotein secretion by d-galactosamine

    PubMed Central

    Bauer, Christian H.; Lukaschek, Rainer; Reutter, Werner G.

    1974-01-01

    galactosamine by: (a) inhibition of protein synthesis leading to a diminution of the endogenous acceptor pool of the galactosyltransferase; (b) inhibition of the galactosyltransferase activity by galactosamine metabolites and (c) replacement of UDP-galactose by UDP-galactosamine. ImagesPLATE 1PLATE 2 PMID:4441378

  18. Seismic observations of large-scale deformation at the bottom of fast-moving plates

    NASA Astrophysics Data System (ADS)

    Debayle, Eric; Ricard, Yanick

    2014-05-01

    We present a new tomographic model of azimuthal anisotropy in the upper mantle and discuss in details the geodynamical causes of this anisotropy. Our model improves upon DKP2005 seismic model (Debayle et al., 2005) through a larger dataset (expanded by a factor ~ 4) and a new approach which allows us to better extract fundamental and higher mode information. Our results confirm that on average, azimuthal anisotropy is only significant in the uppermost 200-250 km of the upper mantle where it decreases regularly with depth. We do not see a significant difference in the amplitude of anisotropy beneath fast oceanic plates, slow oceanic plates or continents. The anisotropy projected onto the direction of present plate motion shows a very specific relation with the plate velocity; it peaks in the asthenosphere around 150 km depth, it is very weak for plate velocities smaller than 3 cm yr-1, increases significantly between 3 and 5 cm yr-1, and saturates for plate velocities larger than 5 cm yr-1. Plate-scale present-day deformation is remarkably well and uniformly recorded beneath the fastest moving plates (India, Coco, Nazca, Australia, Philippine Sea and Pacific plates). Beneath slower plates, plate-motion parallel anisotropy is only observed locally, which suggests that the mantle flow below these plates is not controlled by the lithospheric motion (a minimum plate velocity of around 4 cm yr-1 is necessary for a plate to organize the flow in its underlying asthenosphere). The correlation of oceanic anisotropy with the actual plate motion in the shallow lithosphere is very weak. A better correlation is obtained with the fossil accretion velocity recorded by the gradient of local seafloor age. The transition between frozen-in and active anisotropy occurs across the typical age- isotherm that defines the bottom of the thermal lithosphere around 1100 °C. Under fast continents (mostly under Australia and India), the present day velocity orients also the anisotropy in a

  19. Calcium content and calcium exchange in dark-adapted toad rods.

    PubMed Central

    Fain, G L; Schröder, W H

    1985-01-01

    inaccessible to exchange under physiological conditions, probably because it is sequestered within the disks which in intact rods appear to be nearly impermeable to Ca in darkness. Images PLATE 1 PLATE 2 PMID:3935778

  20. Studies of the congenitally goitrous sheep. Iodoproteins of the goitre

    PubMed Central

    Falconer, Ian R.; Roitt, I. M.; Seamark, R. F.; Torrigiani, G.

    1970-01-01

    detected in goitre tissue from untreated or thyroxine-treated animals, it was possible that the genetic defect causing goitre resulted in an abnormal thyroglobulin, incapable of being iodinated but immunologically reactive. ImagesPLATE 1PLATE 2 PMID:5419739

  1. Near-infrared studies of embedded star clusters

    NASA Astrophysics Data System (ADS)

    Park, Chan

    The Fan Mountain Near-Infrared Camera, FanCam, features an 8.7'x8.7' field of view on a 1024x1024 Teledyne Imaging Sensors HAWAII-1 detector array. The instrument mounts at the f/15.5 focus of the 31 inch telescope. Its seeing-limited optical design, optimized for the JHK atmospheric bands, includes a field stop at the telescope focus, a doublet collimator, two 8-position filterwheels straddling a Lyot stop, and a doublet reimager. The 0.51''pixel-1 plate scale leads to a slightly oversampled point spread function for the typical seeing of 1.5''. The entire optical train is encased in a cryogenic dewar cooled by a closed-loop cooling system. Chapter 2 describes the camera design and some early results of camera performance test. Long term near-infrared, J, H, and Ks, photometric monitoring of the embedded cluster NGC 1333 is presented in Chapter 3. We employ the Stetson variability index and reduced chi 2 to identify variable objects. Color-magnitude and color-color diagrams demonstrate that NGC 1333 is extremely young and highly extincted. Light curves in all three bands are well correlated. The spatial distribution of variable stars shows a strong correlation with the peak of the extinction map while non-variable stars are evenly spread over the whole field of view. Spitzer-2MASS-identified IR excess YSOs and Chandra X-ray sources were compared with our variable stars. A total of 25 previously-unknown member candidates are presented, with 15 objects in the mass range of brown dwarfs. The IMF and mass distribution of the cluster are presented. We discuss the implication of Ks vs. H--Ks color-magnitude diagram slope statistics in view of the evolutionary sequence of young star-forming embedded clusters. Another long term near-infrared, J, H, and Ks, photometric monitoring performed with FanCam for the embedded cluster NGC 7129 is presented in Chapter 4.

  2. First Results from a Forward, 3-Dimensional Regional Model of a Transpressional San Andreas Fault System

    NASA Astrophysics Data System (ADS)

    Fitzenz, D. D.; Miller, S. A.

    2001-12-01

    We present preliminary results from a 3-dimensional fault interaction model, with the fault system specified by the geometry and tectonics of the San Andreas Fault (SAF) system. We use the forward model for earthquake generation on interacting faults of Fitzenz and Miller [2001] that incorporates the analytical solutions of Okada [85,92], GPS-constrained tectonic loading, creep compaction and frictional dilatancy [Sleep and Blanpied, 1994, Sleep, 1995], and undrained poro-elasticity. The model fault system is centered at the Big Bend, and includes three large strike-slip faults (each discretized into multiple subfaults); 1) a 300km, right-lateral segment of the SAF to the North, 2) a 200km-long left-lateral segment of the Garlock fault to the East, and 3) a 100km-long right-lateral segment of the SAF to the South. In the initial configuration, three shallow-dipping faults are also included that correspond to the thrust belt sub-parallel to the SAF. Tectonic loading is decomposed into basal shear drag parallel to the plate boundary with a 35mm yr-1 plate velocity, and East-West compression approximated by a vertical dislocation surface applied at the far-field boundary resulting in fault-normal compression rates in the model space about 4mm yr-1. Our aim is to study the long-term seismicity characteristics, tectonic evolution, and fault interaction of this system. We find that overpressured faults through creep compaction are a necessary consequence of the tectonic loading, specifically where high normal stress acts on long straight fault segments. The optimal orientation of thrust faults is a function of the strike-slip behavior, and therefore results in a complex stress state in the elastic body. This stress state is then used to generate new fault surfaces, and preliminary results of dynamically generated faults will also be presented. Our long-term aim is to target measurable properties in or around fault zones, (e.g. pore pressures, hydrofractures, seismicity

  3. The presence of lysophosphatidylcholine in chromaffin granules

    PubMed Central

    Arthur, Gilbert; Sheltawy, Ayman

    1980-01-01

    diffusion of [14C]dopamine was measured across their membranes. Both types of liposomes had similar capture volumes (0.5μl/μmol of phospholipid), and the activation energies of the exchange diffusion of dopamine were also similar (31kJ/mol). These results indicate that the presence of this proportion of lysophosphatidylcholine in chromaffin-granule membranes is not likely to influence their barrier properties towards catecholamines. ImagesPLATE 1PLATE 2 PMID:7236208

  4. Feline cerebral veins and arteries: comparison of autonomic innervation and vasomotor responses

    PubMed Central

    Edvinsson, Lars; McCulloch, James; Uddman, Rolf

    1982-01-01

    ). ImagesPlate 1Plate 2 PMID:6180162

  5. Searching for the Lost Jurassic and Cretaceous Ocean Basins of the Circum-Arctic Linking Plate Models and Seismic Tomography

    NASA Astrophysics Data System (ADS)

    Shephard, G. E.; Müller, R.

    2012-12-01

    The tectonic evolution of the circum-Arctic since the breakup of Pangea involves the opening and closing of ocean basins including the Oimyakon, Angayucham, South Anuyi, Amerasia and Eurasia basins. The time-dependent configurations and kinematic history of the basins, adjacent continental terranes, and subduction zones involved are not well understood, and many published tectonic models for particular regions are inconsistent with models for adjacent areas. The age, location, geometry and convergence rates of the subduction zones associated with these ancient ocean basins since at least the Late Jurassic have implications for mantle structure, which can be used as an additional constraint for building plate and plate boundary models. Here we integrate an analysis of both surface and deep mantle observations back to 200 Ma. Based on a digitized set of tectonic features with time-dependent rotational histories we present a refined plate model with topologically closed plate polygons for the circum-Arctic with particular focus on the northern Pacific, Siberian and Alaskan margins (Fig 1). We correlate the location, geometry and timing of subduction zones with associated seismic velocities anomalies from global P and S wave tomography models across different depths. We design a plate model that best matches slabs imaged in seismic tomography in an iterative fashion. This match depends on a combination of relative and absolute plate motions. Therefore we test two end-member absolute plate motion models, evaluating a paleomagnetic model and a model based on hotspot tracks and large igneous provinces. This method provides a novel approach to deciphering the Arctic tectonic history in a global context. Fig 1:Plate reconstruction at 200Ma and 140Ma, visualized using GPlates software. Present-day topography raster (ETOPO2) segmented into major tectonic elements of the circum-Arctic. Plate boundaries delineated in black and selected subduction and arc features labeled in

  6. Requirements for imaging vulnerable plaque in the coronary artery using a coded aperture imaging system

    NASA Astrophysics Data System (ADS)

    Tozian, Cynthia

    A coded aperture1 plate was employed on a conventional gamma camera for 3D single photon emission computed tomography (SPECT) imaging on small animal models. The coded aperture design was selected to improve the spatial resolution and decrease the minimum detectable activity (MDA) required to image plaque formation in the APoE (apolipoprotein E) gene deficient mouse model when compared to conventional SPECT techniques. The pattern that was tested was a no-two-holes-touching (NTHT) modified uniformly redundant array (MURA) having 1,920 pinholes. The number of pinholes combined with the thin sintered tungsten plate was designed to increase the efficiency of the imaging modality over conventional gamma camera imaging methods while improving spatial resolution and reducing noise in the image reconstruction. The MDA required to image the vulnerable plaque in a human cardiac-torso mathematical phantom was simulated with a Monte Carlo code and evaluated to determine the optimum plate thickness by a receiver operating characteristic (ROC) yielding the lowest possible MDA and highest area under the curve (AUC). A partial 3D expectation maximization (EM) reconstruction was developed to improve signal-to-noise ratio (SNR), dynamic range, and spatial resolution over the linear correlation method of reconstruction. This improvement was evaluated by imaging a mini hot rod phantom, simulating the dynamic range, and by performing a bone scan of the C-57 control mouse. Results of the experimental and simulated data as well as other plate designs were analyzed for use as a small animal and potentially human cardiac imaging modality for a radiopharmaceutical developed at Bristol-Myers Squibb Medical Imaging Company, North Billerica, MA, for diagnosing vulnerable plaques. If left untreated, these plaques may rupture causing sudden, unexpected coronary occlusion and death. The results of this research indicated that imaging and reconstructing with this new partial 3D algorithm improved

  7. Effects of differential pulse frequencies of chicken gonadotrophin-releasing hormone-I (cGnRH-I) on laying hen gonadotrope responses in vitro.

    PubMed

    Soñez, M C; Soñez, C A; Mugnaini, M T; Haedo, M; Romera, S A; Lombardo, D M; Delhon, G A

    2010-12-01

    The aim of this work was to determine the effects of cGnRH I pulse frequencies on FSH and LH release and the changes in features and number of cultured laying hen FSH-cells and LH-cells in vitro. Primary adenohypophyseal cell cultures taken from laying hens were stimulated by four 5 min pulses using 1 or 10 nM cGnRH, administered with interpulses between pulses at 15, 30 or 60 min. Pulse frequencies and dose dependent effects were examined in six separate experiments including two controls. After the last interpulse time, the supernatants were collected and stored at -70° C until the performance of an indirect enzyme-linked immunosorbent assay (ELISA) using chicken LH and chicken FSH antisera at 1:1000 and 1:2000 dilutions, respectively. Supernatants were coated in duplicate on the inner surface of Immulon 2 plates and later blocked with the optimal solutions. They were incubated with each antiserum and subsequently with isotype-specific peroxidase-labeled anti-rabbit antibodies. Hydrogen peroxide/o-phenylenediamine was added as substrate/chromogen and the optical density (OD) was determined at 492 nm. The ABC immunocytochemical method was performed to characterize and re-count the gonadotropes employing anti-chicken FSH and anti-chicken LH as primary antibodies. The number of FSH-LH cells was obtained using stereological analysis and the data were statistically processed. The ODs obtained for each anti-hormone were compared with the control groups and with each other. Significant differences were found in number of aggregated-positive LH cells, which decreased with 1 nM cGnRH-I, 15 vs. 30 min pulses, increased with 30 vs. 60 min pulses, and also with 10 nM cGnRH-I, 30 vs. 60 min pulses. Aggregated positive FSH cells, however, did not show significant differences in percentage at any GnRH dose or pulse frequencies, but did show activity at low pulse frequencies of 15 and 30 min. The results suggest that LH cells varied in percentage in a dose dependent manner at

  8. Fuel Fabrication Capability Research and Development Plan

    SciTech Connect

    Senor, David J.; Burkes, Douglas

    2014-04-17

    is between now and 2016 when the candidate processes are down-selected in preparation for the MP-1, FSP-1, and MP-2 plate manufacturing campaigns. A number of key risks identified by the FFC are discussed in this plan, with recommended mitigating actions for those activities within FFC, and identification of risks that are impacted by activities in other areas of the Convert Program. The R&D Plan does not include discussion of FFC initiatives related to production-scale manufacturing of fuel (e.g., establishment of the Pilot Line Production Facility), rather, the goal of this plan is to document the R&D activities needed ultimately to enable high-quality and cost-effective production of the fuel by the commercial fuel fabricator. The intent is for this R&D Plan to be a living document that will be reviewed and updated on a regular basis (e.g., annually) to ensure that FFC R&D activities remain properly aligned to the needs of the Convert Program. This version of the R&D Plan represents the first annual review and revision.

  9. Decremental conduction of the visual signal in barnacle lateral eye

    PubMed Central

    Shaw, Stephen R.

    1972-01-01

    the absence of regenerative activity implicate the slow potential itself as the visual signal. But there remains the alternative that light triggers some unknown transmission process, of which the slow potential is only an incidental by-product. If this were so, artificially imposed changes of membrane potential should not duplicate the action of light in promoting synaptic transmission. To test this, receptors were polarized by currents through the pipette whilst visually driven post-synaptic cells in the oesophageal connectives were being monitored. Currents could effectively substitute for lights to produce post-synaptic impulse trains of similar form and latency, confirming that the potential change produced by light is the normal visual signal. 8. Only increases of receptor membrane potential stimulate the particular post-synaptic axons examined, which give `off' responses to light. Transmission from the receptors is a voltage-dependent process which is most sensitive when a receptor is hyperpolarized from an already depolarized level. 9. The discrimination of small visual signals from intrinsic axon noise is discussed, and should pose no problem in the case of the barnacle, where the smallest effective signal measured was about 0·3 mV in the soma. In other eyes where the problem may be more severe, electrical junctions between receptors could significantly improve the signal/noise ratio. ImagesPlate 2Plate 1 PMID:4110376

  10. Contractions induced by a calcium-triggered release of calcium from the sarcoplasmic reticulum of single skinned cardiac cells.

    PubMed Central

    Fabiato, A; Fabiato, F

    1975-01-01

    . This gradation was deemed incompatible with a simple regenerative process, which should produce an all-or-nothing response. Additional process, such as a modulation of the Ca2+ release by free [Mg2+] and [ADP] may help to explain the gradation of the contractions. 7. It was concluded that a Ca2+-triggered release of Ca2+ from the SR of rat ventricular cells may amplify the Ca2+ flux crossing the sarcolemma during the plateau of the action potential, thereby permitting the activation of the myofilaments. Images Plate 2 Plate 1 PMID:809571

  11. Could borate have played a role in the RNA World?

    NASA Astrophysics Data System (ADS)

    Grew, E. S.; Bada, J. L.; Hazen, R. M.

    2012-12-01

    Two scenarios have been proposed for boron to play a critical role in the stabilization of ribose and other sugars in the ribonucleic acid (RNA) World, >3.8 Ga ago. One scenario envisages oligomeric RNA being synthesized in subaerial intermountane desert valleys in which groundwater was enriched in borate from breakdown of tourmaline (Benner et al. 2012 doi: 10.1021/ar200332w). In the alternative scenario, borates are enriched in hydrothermal environments (<150°C) in oceanic crust where ferromagnesian minerals are altered to brucite, serpentine and other minerals that can extract borate from the circulating seawater (Holm et al. 2006 doi:10.1186/1467-4866-7-7). Both scenarios presume that (1) B concentrations in non-marine water or sea water were about the same at >3.8 Ma as they are today and (2) plate tectonics was the prevailing regime. The postulated non-marine borate deposits would have been associated with continental collision and subduction with volcanism releasing B, whereas in the second scenario, ocean floor caught up in an early phase of subduction is considered a favorable site for borate formation. Because borate deposits are typically ephemeral and poorly preserved, the lack of evidence in the geologic record for these scenarios does not invalidate them. For example, the oldest reported non-marine borate deposits analogous to the type postulated in first scenario are only 20 Ma, but metamorphosed borates of Precambrian age have been interpreted to have non-marine evaporite precursors, the oldest being 2.4-2.1 Ga in the Liaoning-Jilin area, China. The first B minerals so far reported in the geologic record are metamorphic dravite-schorl tourmalines in the 3.7-3.8 Ga Isua supracrustal belt (southern West Greenland), where there is good evidence for seafloor spreading and subduction. The precursors to the Isua tourmalines are reported to include B-bearing marine clay minerals and detrital tourmaline. The relatively high Li contents in zircon from Jack

  12. Harnessing Solar Energy Using Photosynthetic and Organic Pigments

    NASA Astrophysics Data System (ADS)

    Fitzsimons, Toby Ryan

    Fossil fuels are a finite energy resource that must be supplemented or replaced by more stable forms of electrical energy. Solar technology research strives to supplement and provide eventual replacement for fossil fuel technology. This experiment focused on the use of natural pigments as photo-sensitizers in the current generation of solar cells called dye sensitized solar cells (DSSCs). Pigments from purified chlorophyll a, chlorophyll b, chlorophyll a/b, crude spinach (Spinacia oleracea) extract, phycocyanin, and chlorophyllin were used to construct DSSCs and evaluated, along with a control containing no pigment, for solar energy conversion. The anode of the solar cells consisted of titanium dioxide (TiO2) plates soaked in pigment solutions for twenty-four hours. The plates were assembled, along with an electrolyte sandwiched between cells, and a platinum-coated counter plate that functioned as the cathode. A gasket seal was placed between the plates and held together with rubber bands. The DSSCs were each tested for a maximum power (Pmax) point and a resistor was selected that corresponded to the resistance at that point. The cells were randomly placed into a power block assembly located in an environmental chamber with lighting that provided an average of 27,590 lumens at the surface of DSSCs. With appropriate resistors in place, the cells were subjected to twelve-hour days and twelve-hour nights for ten days, and measurements were recorded every ten minutes. Data were collected to obtain values for voltage in millivolts (mV), current in microamps (microA), and power in microwatts (microW), as well as beginning and ending efficiencies in converting light to usable energy. Voltages were substantially higher during the day than at night for all pigments, except for the control, indicating that the pigments functioned as DSSCs. Hence, only daytime values were used for data analysis. Voltage during the ten-day experiment ranged from 3.99 to 274 mV; current ranged

  13. Voltage clamp of bull-frog cardiac pace-maker cells: a quantitative analysis of potassium currents.

    PubMed Central

    Giles, W R; Shibata, E F

    1985-01-01

    rectification. A Hodgkin-Huxley analysis of the kinetics of IK, including a demonstration that the envelope of tails quantitatively matches the time course of the onset of IK during a prolonged depolarizing clamp step has been completed. The steady-state activation variable (n infinity) of IK spans the voltage range approximately -40 to +10 mV. It is well-fitted by a Boltzmann distribution function with half-activation at -20 mV. The time course of decay of IK is a single exponential. However, the activation or onset of IK shows clear sigmoidicity in the range of potentials from the activation threshold (-40 mV) to 0 mV.(ABSTRACT TRUNCATED AT 400 WORDS) Images PLATE 1 PLATE 2 PMID:2416914

  14. Geophysical constraints on geodynamic processes at convergent margins: A global perspective

    NASA Astrophysics Data System (ADS)

    Artemieva, Irina; Thybo, Hans; Shulgin, Alexey

    2016-04-01

    Convergent margins, being the boundaries between colliding lithospheric plates, form the most disastrous areas in the world due to intensive, strong seismicity and volcanism. We review global geophysical data in order to illustrate the effects of the plate tectonic processes at convergent margins on the crustal and upper mantle structure, seismicity, and geometry of subducting slab. We present global maps of free-air and Bouguer gravity anomalies, heat flow, seismicity, seismic Vs anomalies in the upper mantle, and plate convergence rate, as well as 20 profiles across different convergent margins. A global analysis of these data for three types of convergent margins, formed by ocean-ocean, ocean-continent, and continent-continent collisions, allows us to recognize the following patterns. (1) Plate convergence rate depends on the type of convergent margins and it is significantly larger when, at least, one of the plates is oceanic. However, the oldest oceanic plate in the Pacific ocean has the smallest convergence rate. (2) The presence of an oceanic plate is, in general, required for generation of high-magnitude (M N 8.0) earthquakes and for generating intermediate and deep seismicity along the convergent margins. When oceanic slabs subduct beneath a continent, a gap in the seismogenic zone exists at depths between ca. 250 km and 500 km. Given that the seismogenic zone terminates at ca. 200 km depth in case of continent-continent collision, we propose oceanic origin of subducting slabs beneath the Zagros, the Pamir, and the Vrancea zone. (3) Dip angle of the subducting slab in continent-ocean collision does not correlate neither with the age of subducting oceanic slab, nor with the convergence rate. For ocean-ocean subduction, clear trends are recognized: steeply dipping slabs are characteristic of young subducting plates and of oceanic plates with high convergence rate, with slab rotation towards a near-vertical dip angle at depths below ca. 500 km at very high

  15. Organization of synaptic transmission in the mammalian solitary complex, studied in vitro.

    PubMed Central

    Champagnat, J; Denavit-Saubié, M; Grant, K; Shen, K F

    1986-01-01

    solitary tract stimulation. Spontaneous excitatory potentials of more than 0.5 mV were not seen in neurones with prolonged reduced excitability. In these neurones, after intracellular injection of choride ions, reversed unitary i.p.s.p.s formed a background activity which was increased following stimulation of the solitary tract. 6. Neurones with prolonged reduced excitability were found in the medial, ventral and ventrolateral part of the nucleus tractus solitarius and in the dorsal vagal motor nucleus where they were identified by their antidromic response to stimulation ventral and lateral to the tractus solitarius.(ABSTRACT TRUNCATED AT 400 WORDS) Images PLATE 1 PLATE 2 PMID:3040963

  16. Characteristics of sarcoplasmic reticulum from slowly glycolysing and from rapidly glycolysing pig skeletal muscle post mortem

    PubMed Central

    McIntosh, David B.; Berman, Mervyn C.; Kench, James E.

    1977-01-01

    associated Ca2+ (approx. 0.10μmol of Ca2+/mg of protein) during the rapid phase, compared with 30% (approx. 0.17μmol of Ca2+/mg of protein) in those from slowly glycolysing muscle. The efflux rate during the slower phase was comparable in both types of vesicles. Analysis of the temperature-dependence of (Ca2++Mg2+)-stimulated ATPase activity revealed that a high-activation-energy process operating in the temperature range 31–45°C in the intermediate and light fractions from slowly glycolysing muscle was not apparent in vesicles from rapidly glycolysing muscle. Conditions that result in the prolonged activation of glycogenolysis in pig muscle post mortem primarily affect the protein components of the sarcoplasmic-reticular membrane, giving rise to a loss of loosely associated proteins. The function of the membranes observed under these conditions does not appear to be due to enhanced permeability of the membrane to Ca2+ and may be the result of a defect in the transport of Ca2+ into the vesicles. ImagesPLATE 1PLATE 2 PMID:145857

  17. Sub-crop geologic map of pre-Tertiary rocks in the Yucca Flat and northern Frenchman Flat areas, Nevada Test Site, southern Nevada

    SciTech Connect

    Cole, J.C.; Harris, A.G.; Wahl, R.R.

    1997-10-02

    for ground water flow through pre-Tertiary rocks beneath the Yucca Flat and northern Frenchman Flat areas, and has consequences for ground water modeling and model validation. Our data indicate that the Mississippian Chainman Shale is not laterally extensive confining unit in the western part of the basin because it is folded back onto itself by the convergent structures of the Belted Range and CP thrust systems. Early and Middle Paleozoic limestone and dolomite are present beneath most of both basins and, regardless of structural complications, are interpreted to form a laterally continuous and extensive carbonate aquifer. Structural culmination that marks the French Peak accommodation zone along the topographic divide between the two basins provides a lateral pathway through highly fractured rock between the volcanic aquifers of Yucca Flat and the regional carbonate aquifer. This pathway may accelerate the migration of ground-water contaminants introduced by underground nuclear testing toward discharge areas beyond the Nevada Test Site boundaries. Predictive three-dimensional models of hydrostratigraphic units and ground-water flow in the pre-Tertiary rocks of subsurface Yucca Flat are likely to be unrealistic due to the extreme structural complexities. The interpretation of hydrologic and geochemical data obtained from monitoring wells will be difficult to extrapolate through the flow system until more is known about the continuity of hydrostratigraphic units. 1 plate

  18. Triple junctions and multi-directional extension of the lithosphere

    NASA Astrophysics Data System (ADS)

    Gerya, Taras; Burov, Evgenii

    2016-04-01

    Triple junctions are among the most remarkable features of global plate tectonics but their nucleation and evolution remains debatable. Divergent (R-R-R) triple junctions (at 120o and T junctions) are particular ones since their stability depends on the exact values of the relative velocities of multi-directional plate motions and hence is strongly affected by plate rheology and processes of crustal and lithospheric accretion. It is commonly accepted (although not quantitatively tested) that the geometry and stability of R-R-R triple junctions should be related to the intuitive geometric considerations that 3-branch configurations should be more "stable" compared to >3-branch configurations (e.g. quadruple junctions) under conditions of long-term multi-directional extension on a 3D Earth surface. Indeed, it has been long-time suggested that triple junctions result from evolution of short-lived quadruple junctions, yet, without providing a consistent mechanical explanation or experimental demonstration of this process, due to the rheological complexity of the breaking lithosphere subsequently subjected to complex oceanic crustal and lithospheric accretion processes. Therefore, a complete 3D thermo-mechanically consistent approach is needed to understand the processes of formation of multi-branch junctions. Here, we study numerically the processes of multi-branch junctions formation under condition of multi-directional lithospheric extension. We use high-resolution 3D numerical magmatic-thermo-mechanical experiments that take into account realistic thermo-rheological structure and rheology of the lithosphere and account for crustal and lithospheric accretion processes. We find that two major types of quadruple and triple junctions are formed under bi-directional or multidirectional far-field stress field: (1) plate rifting junctions are formed by the initial plate fragmentation and can be subsequently re-arranged into (2) oceanic spreading junctions controlled by the

  19. Supraspinal morphine and descending inhibitions acting on the dorsal horn of the rat.

    PubMed Central

    Dickenson, A H; Le Bars, D

    1987-01-01

    following the microinjection (a mean 77% reduction) and then returned towards control values. All but three of the corresponding microinjection sites were such as to include the medio-ventral p.a.g. including the nucleus raphé dorsalis. In contrast none of the cases where d.n.i.c. was unaltered included microinjection sites in this region. 5. No relationship was found between the changes in d.n.i.c. and the number of spikes evoked in the control sequences, or the changes in the C-fibre responses. 6. Autoradiographic controls using [3H]morphine showed a large diffusion of the drug within an area of about 0.75 mm around the tip of the cannula.(ABSTRACT TRUNCATED AT 400 WORDS) Images Plate 1 Plate 2 PMID:3309265

  20. Intracellular sodium and the differentiation of amphibian embryonic neurones

    PubMed Central

    Breckenridge, Lorna J.; Warner, Anne E.

    1982-01-01

    ]o was abolished when [Ca]o was simultaneously lowered to 0·05 mM. 11. Tadpoles from embryos treated with low extracellular sodium together with strophanthidin during neurulation had normal eyes compared to those treated with strophanthidin alone. 12. Measurement of the intracellular sodium concentration ([Na]i) with sodium-sensitive micro-electrodes put [Na]i at about 30 mM before the neural folds lift. As the sodium pump is activated (stages 14½-15)[Na]i in the neural plate falls; by the end of the mid-neural fold stage it is less than 10 mM. 13. Addition of 5 × 10-6M-strophanthidin to the bathing fluid before activation of the sodium pump prevented the fall in [Na]i; in embryos where [Na]i had begun to drop strophanthidin produced a rise to about 30 mM. 14. When 10 mM-calcium was present along with strophanthidin [Na]i fell to about 17 mM during neurulation, despite inhibition of the sodium pump. 15. It is concluded that it is unlikely that either abolition of the normal increase in resting potential or a fall in gap junction permeability is responsible for the reduction in neural differentiation produced by blocking the sodium pump during neurulation. 16. The results are consistent with the view that strophanthidin achieves its effect by preventing the fall in [Na]i that occurs during normal neurulation because of activation of the sodium pump. They are discussed in the light of this suggestion. ImagesPlate 1Plate 2 PMID:7153933

  1. Plate boundary deformation at the latitude of the Salton Trough - northern Gulf of California (Invited)

    NASA Astrophysics Data System (ADS)

    Stock, J. M.

    2013-12-01

    Along the Pacific-North America plate boundary zone, the segment including the southern San Andreas fault to Salton Trough and northern Gulf of California basins has been transtensional throughout its evolution, based on Pacific-North America displacement vectors calculated from the global plate circuit (900 × 20 km at N54°W since 20 Ma; 460 × 20 km at N48°W since 11 Ma). Nevertheless, active seismicity and focal mechanisms show a broad zone of plate boundary deformation within which the inferred stress regime varies locally (Yang & Hauksson 2013 GJI), and fault patterns in some regions suggest ongoing tectonic rotation. Similar behavior is inferred to have occurred in this zone over most of its history. Crustal structure in this region is constrained by surface geology, geophysical experiments (e.g., the 2011 Salton Seismic Imaging Project (SSIP), USGS Imperial Valley 1979, PACE), and interdisciplinary marine and onland studies in Mexico (e.g., NARS-Baja, Cortes, and surveys by PEMEX). Magnetic data (e.g., EMAG-2) aids in the recognition of large-scale crustal provinces and fault boundaries in regions lacking detailed geophysical surveys. Consideration of existing constraints on crustal thickness and architecture, and fault and basin evolution suggests that to reconcile geological deformation with plate motion history, the following additional factors need to be taken into account. 1) Plate boundary displacement via interacting systems of rotating blocks, coeval with slip on steep strike slip faults, and possibly related to slip on low angle extensional faults (e.g, Axen & Fletcher 1998 IGR) may be typical prior to the onset of seafloor spreading. This fault style may have accommodated up to 150 km of plate motion in the Mexican Continental Borderland and north of the Vizcaino Peninsula, likely between 12 and 15 Ma, as well as explaining younger rotations adjacent to the Gulf of California and current deformation southwest of the Salton Sea. 2) Geophysical

  2. Action potentials of embryonic dorsal root ganglion neurones in Xenopus tadpoles.

    PubMed Central

    Baccaglini, P I

    1978-01-01

    + abolishes the spike but TTX does not block it. It is present in cells of all sizes. The mean resting potential is less than that of cells with Na+-dependent type I action potentials, while the mean input resistance is greater. 6. Tetraethylammonium chloride (TEA) prolongs the different kinds of action potentials. The amount of prolongation varies among cells with a given type of action potential, so that no distinction could be made of the different actionpotential types based on the effect of TEA. 7. The percent of cells with each kind of action potential varies with the developmental age of the animal. The number of cells with Ca2+ and Ca2+/Na+ action potentials decreases with age, while the number of cells with a Na+ type I action potentials increases. The Na+ type II action potential appears only at later stages. 8... Images Plate 1 Plate 2 PMID:722591

  3. Structural and functional definition of the motor cortex in the monkey (Macaca fascicularis)

    PubMed Central

    Sessle, B. J.; Wiesendanger, M.

    1982-01-01

    ) although it is difficult to establish the precise transition from area 4 to area 6. 6. Posteriorly, the `micro-excitable cortex' was found to be limited to regions cytoarchitectonically delineated as area 4 and did not include area 3a. On the other hand, low-threshold forelimb proprioceptive afferent inputs appeared restricted to area 3a neurones in the deeply anaesthetized animal. Corticospinal neurones were very dense in area 4, and there was a clear decrease in their occurrence in more caudal areas. However, scattered nests of corticospinal neurones were noted in areas 3a, 3b, 2, 1 and 5. It remains to be seen whether these scattered nests could be directly involved in motor control or whether they may modulate ascending somatosensory transmission, and whether they rely on sensory feed-back or inputs from other central areas for their spinal effects. ImagesPlate 1Plate 2 PMID:7097574

  4. Concomitant changes in formaldehyde-induced fluorescence of dopamine interneurones and in slow inhibitory post-synaptic potentials of the rabbit superior cervical ganglion, induced by stimulation of the preganglionic nerve or by a muscarinic agent

    PubMed Central

    Libet, B.; Owman, Ch.

    1974-01-01

    .-i.p.s.p. response and the dopamine fluorescence of the small intensely fluorescent cells, in ganglia already subjected either to the conditioning stimulation of the preganglionic nerve or to the action of bethanechol. 7. It is concluded that (a) preganglionic impulses, by a cholinergic muscarinic synaptic action, can induce a release of dopamine from dopamine interneurones (small intensely fluorescent cells) in the superior cervical ganglion, (b) the ability of the ganglion to respond with a s.-i.p.s.p. to orthodromic input may be viewed as being dependent on the supply of functionally releasable dopamine in these interneurones, (c) the functionally releasable transmitter in vitro appears to comprise roughly 50% of the total dopamine content of the interneurones, and (d) the results fulfil some of the requirements of the hypothesis that a dopamine interneurone is activated muscarinically by preganglionic nerve impulses and mediates the production of s.-i.p.s.p. in sympathetic ganglion cells. ImagesPlate 1Plate 2 PMID:4825476

  5. THE USE OF DI WATER TO MITIGATE DUSTING FOR ADDITION OF DWPF FRIT TO THE SLURRY MIX EVAPORATOR

    SciTech Connect

    Hansen, E.

    2010-07-21

    objective of this task is to perform bench scale testing on various frits that have been used at DWPF or in test programs at SRNL to determine the quantity of de-ionized (DI) water required to mitigate dusting per mass basis of frit. The quantity of DI water required was determined visually by observing the effluent port of the mixer, and DI water addition was made to the point where no visible dust was observed leaving the effluent port. A total of eight different frits were selected for testing. Secondary objectives in this task include the following: (1) Video taping of the de-dusting procedure, (2) Particle size distribution analyses of the dry and wetted frits at the weight fraction of water required for de-dusting, (3) Plate flow tests to determine angle of flow and quantity of material remaining on plate at 90 degrees, (4) Microscopy of dry and wetted frit, and (5) Effect of excess water for selected frits on plate flow. The above analyses were performed within one hour of water addition, to minimize the effect of evaporative water losses. To better understand the size of dust particles, perform settling tests on selected frits and capture the fines. Analyze the fines for particle size distribution. Finally, it is expected that the surface area of frit is an important parameter in the quantity of water required for dust mitigation. An analysis of particle size distribution (PSD) data of as-received frit analyzed by SRNL over the past two to three years will be performed to determine the variation in the distribution of as-received frit. The following objectives were stated in the Technical Task Request4 as objectives that given adequate time would provide insight in helping DWPF in assessing equipment or processes for de-dusting and processing of dry frit. Due to time constraints, commercial methods for dedusting are provided. These results are detailed in section 3.7. Obtain design information from Hanford with respective to equipment used for dedusting. Suggestions

  6. The frequency selectivity of auditory nerve fibres and hair cells in the cochlea of the turtle

    PubMed Central

    Crawford, A. C.; Fettiplace, R.

    1980-01-01

    stimulation, the hair cell voltage fluctuated continuously about its mean level. The principal frequency components in the noise were concentrated around the c.f. of the cell. The voltage noise in the hair cells showed no significant cross-correlation with sound pressure fluctuations at the tympanum. ImagesPLATE 1PLATE 2 PMID:7463380

  7. AB106. Differential regulation of LncRNA-SARCC suppresses VHL-mutant RCC cell proliferation yet promotes VHL-normal RCC cell proliferation via modulating androgen receptor/HIF-2α/C-MYC axis under hypoxia

    PubMed Central

    Zhai, Wei

    2016-01-01

    ), treated with RNase-free DNase I (Roche), and purified with an RNeasy Mini Kit (Qiagen, Valencia, CA, USA). One milligram of whole-cell lysates from SW839 cells were incubated with 3 µg of purified biotinylated transcripts for 1 hour at 25 °C and complexes were isolated with streptavidin agarose beads (Invitrogen). The AR protein present in the pull-down material was detected by standard immunoblot analysis. Chromatin immunoprecipitation assay (ChIP)—cells were cross-linked with 4% formaldehyde for 10 minutes followed by cell collection and sonication with a predetermined power to yield genomic DNA fragments of 300–1,000 bp long. Lysates were precleared sequentially with normal rabbit IgG (sc-2027, Santa Cruz Biotechnology) and protein A-agarose. Anti-AR antibody (2.0 µg) was added to the cell lysates and incubated at 4 °C overnight. For the negative control, IgG was used in the reaction. Cell-cycle analysis—cells were plated at a density such that they would be 50% confluent on the day of analysis. Treatment (hypoxia) was then initiated over the next several days, so that all cells were in culture for the same amount of time and at similar confluency when harvested. BrdU analysis was performed following the standard protocol (Becton Dickinson) after a 20 min pulse with 10 mM BrdU. Cells were stained with Alexa 488 anti-BrdU (Invitrogen) and 0.1 M propidium iodide and analyzed in an LSR FACS machine (Becton Dickinson). For proliferation analysis with Hoechst staining, 104 cells were plated on 6-cm2 plates, with staining and counting done according to the manufacturer’s instructions (Invitrogen). Luciferase assay—cells were plated in 24-well plates and transfected with pGL3 reporter constructs using lipofectamine (Invitrogen) according to the manufacturer’s instruction. After transfection, DMEM media was added into the culture with dihydrotestosterone (DHT) with ethanol as vehicle control. pRL-TK was used as internal control. Luciferase activity was measured