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Sample records for determining precise oligosaccharidic

  1. Precise Orbit Determination for ALOS

    NASA Technical Reports Server (NTRS)

    Nakamura, Ryo; Nakamura, Shinichi; Kudo, Nobuo; Katagiri, Seiji

    2007-01-01

    The Advanced Land Observing Satellite (ALOS) has been developed to contribute to the fields of mapping, precise regional land coverage observation, disaster monitoring, and resource surveying. Because the mounted sensors need high geometrical accuracy, precise orbit determination for ALOS is essential for satisfying the mission objectives. So ALOS mounts a GPS receiver and a Laser Reflector (LR) for Satellite Laser Ranging (SLR). This paper deals with the precise orbit determination experiments for ALOS using Global and High Accuracy Trajectory determination System (GUTS) and the evaluation of the orbit determination accuracy by SLR data. The results show that, even though the GPS receiver loses lock of GPS signals more frequently than expected, GPS-based orbit is consistent with SLR-based orbit. And considering the 1 sigma error, orbit determination accuracy of a few decimeters (peak-to-peak) was achieved.

  2. Determination Trial of Nondigestible Oligosaccharide in Processed Foods by Improved AOAC Method 2009.01 Using Porcine Small Intestinal Enzyme.

    PubMed

    Tanabe, Kenichi; Nakamura, Sadako; Omagari, Katsuhisa; Oku, Tsuneyuki

    2015-06-24

    We have previously shown that the Association of Official Analytical Chemists' (AOAC) methods 2001.03 and 2009.01 were not able to measure accurately nondigestible oligosaccharide because they are incapable of hydrolyzing digestible oligosaccharide, leading to overestimation of nondigestible oligosaccharide. Subsequently, we have proposed improved AOAC methods 2001.03 and 2009.01 using porcine small intestinal disaccharidases instead of amyloglucosidase. In the present study, we tried to determine nondigestible oligosaccharide in marketed processed foods using the improved AOAC method (improved method), and the results were compared with those by AOAC method 2009.01. In the improved method, the percentages of recovery of fructooligosaccharide, galactooligosaccharide, and raffinose to the label of processed food were 103.0, 89.9, and 102.1%, respectively. However, the AOAC method 2009.01 overestimated >30% of the quantity of nondigestible oligosaccharide in processed foods, because the margin of error was accepted ±20% on the contents of nondigestible oligosaccharides in processed foods for Japanese nutrition labeling, the improved method thus provided accurate quantification of nondigestible oligosaccharides in processed food and allows a comprehensive determination of nondigestible oligosaccharides.

  3. Enzymatic preparation and structural determination of oligosaccharides derived from sea cucumber (Acaudina molpadioides) fucoidan.

    PubMed

    Yu, Long; Xu, Xiaoqi; Xue, Changhu; Chang, Yaoguang; Ge, Lei; Wang, Yanchao; Zhang, Cuiyu; Liu, Guanchen; He, Chen

    2013-08-15

    Sea cucumber fucoidan is a major bioactive component of sea cucumber. Sea cucumber is widely consumed in East Asian countries as healthy food. Employing the degrading enzyme from the marine bacterium strain Flavobacteriaceae CZ1127, sea cucumber (Acaudina molpadioides) fucoidan oligosaccharides were prepared by enzymatic hydrolysis. The oligosaccharide profile of the hydrolysate was determined by liquid chromatography coupled with mass spectrometry (LC-MS). With the assistance of LC-MS, four major oligosaccharides in the hydrolysate were purified. By using tandem mass spectrometry and nuclear magnetic resonance, delicate structures of the oligosaccharides were verified as α-l-Fucp-1→3-α-l-Fucp(2,4OSO3(2-))-1→3-α-l-Fucp, α-l-Fucp-1→3-α-l-Fucp(2,4OSO3(2-))-1→3-α-l-Fucp-1→3-α-l-Fucp, α-l-Fucp-1→3-α-l-Fucp(2,4OSO3(2-))-1→3-α-l-Fucp-1→3-α-l-Fucp-1→3-α-l-Fucp-1→3-α-l-Fucp(2,4OSO3(2-))-1→3-α-l-Fucp and α-l-Fucp-1→3-α-l-Fucp(2,4OSO3(2-))-1→3-α-l-Fucp-1→3-α-l-Fucp-1→3-α-l-Fucp-1→3-α-l-Fucp(2,4OSO3(2-))-1→3-α-l-Fucp-1→3-α-l-Fucp.

  4. Precision orbit determination of altimetric satellites

    NASA Technical Reports Server (NTRS)

    Shum, C. K.; Ries, John C.; Tapley, Byron D.

    1994-01-01

    The ability to determine accurate global sea level variations is important to both detection and understanding of changes in climate patterns. Sea level variability occurs over a wide spectrum of temporal and spatial scales, and precise global measurements are only recently possible with the advent of spaceborne satellite radar altimetry missions. One of the inherent requirements for accurate determination of absolute sea surface topography is that the altimetric satellite orbits be computed with sub-decimeter accuracy within a well defined terrestrial reference frame. SLR tracking in support of precision orbit determination of altimetric satellites is significant. Recent examples are the use of SLR as the primary tracking systems for TOPEX/Poseidon and for ERS-1 precision orbit determination. The current radial orbit accuracy for TOPEX/Poseidon is estimated to be around 3-4 cm, with geographically correlated orbit errors around 2 cm. The significance of the SLR tracking system is its ability to allow altimetric satellites to obtain absolute sea level measurements and thereby provide a link to other altimetry measurement systems for long-term sea level studies. SLR tracking allows the production of precise orbits which are well centered in an accurate terrestrial reference frame. With proper calibration of the radar altimeter, these precise orbits, along with the altimeter measurements, provide long term absolute sea level measurements. The U.S. Navy's Geosat mission is equipped with only Doppler beacons and lacks laser retroreflectors. However, its orbits, and even the Geosat orbits computed using the available full 40-station Tranet tracking network, yield orbits with significant north-south shifts with respect to the IERS terrestrial reference frame. The resulting Geosat sea surface topography will be tilted accordingly, making interpretation of long-term sea level variability studies difficult.

  5. High precision attitude determination for Magsat

    NASA Astrophysics Data System (ADS)

    Abshire, G.; McCutcheon, R.; Summers, G.; Vanlandingham, F.; Meyers, G.

    1981-08-01

    A two phase approach to attitude determination software development is introduced. The prelaunch planning and software activities connected with the development and testing of the baseline system for processing nominal attitude data for MAGSAT are described and postlaunch analysis and modifications are outlined. Attitude data processing began 5 months after launch so that postlaunch anomalies could be accounted for. Another advantage of the two phase approach is that costs are reduced because the system is not burdened with software dealing with all possible contingencies. A definitive, continuous, time history of the three axis attitude of the spacecraft was generated to a precision of 20 arc sec (one standard deviation), in each axis. Sensor alignment determinations were done continuously because of the deletrious effects of changing alignments on attitude precision.

  6. Precision orbit determination software validation experiment

    NASA Technical Reports Server (NTRS)

    Schutz, B. E.; Tapley, B. D.; Eanes, R. J.; Marsh, J. G.; Williamson, R. G.; Martin, T. V.

    1980-01-01

    This paper presents the results of an experiment which was designed to ascertain the level of agreement between GEODYN and UTOPIA, two completely independent computer programs used for precision orbit determination, and to identify the sources which limit the agreement. For a limited set of models and a seven-day data set arc length, the altitude components of the ephemeris obtained by the two programs agree at the sub-centimeter level throughout the arc.

  7. Oligosaccharides in several Philippine indigenous food legumes: determination, localization and removal.

    PubMed

    Revilleza, M J; Mendoza, E M; Raymundo, L C

    1990-01-01

    The oligosaccharide profile of raw mature seeds of seven different legumes indigenous to the Philippines was measured in 70% ethanol extracts of the seeds by thin layer chromatography using HPTLC plates and quantified by a densitometer. Based on the results, the legumes could be ranked according to decreasing oligosaccharide content or flatulence potential as follows: Sam-samping (Clitoria ternatea) greater than hyacinth bean (Dolichos lablab) greater than sabawel (Mucuna pruriens) greater than lima bean (Phaseolus lunatus) greater than swordbean (Canavalia gladiata) greater than rice bean (Vigna umbellata) greater than jack bean (Canavalia ensiformis). Sam-samping had 4.79% total oligosaccharides and hyacinth bean or batao, 3.66%. A jack bean accession had 1.79% oligosaccharides. Simple processing methods were tested to detoxify the oligosaccharides. Soaking the batao seeds had no effect while boiling even resulted in a net 23-31% increase in the levels of raffinose, stachyose and verbascose. On the other hand, two min of dry roasting resulted in complete removal of oligosaccharides whereas germination resulted in about 30-40% decrease after 1 and 2 days, respectively.

  8. Immobilized Lotus tetragonolobus agglutinin binds oligosaccharides containing the Le(x) determinant.

    PubMed

    Yan, L; Wilkins, P P; Alvarez-Manilla, G; Do, S I; Smith, D F; Cummings, R D

    1997-01-01

    A defined set of oligosaccharides and glycopeptides containing alpha-linked fucose were used to examine the specificity of the immobilized fucose-binding lectin Lotus tetragonolobus agglutinin (LTA1), also known as lotus lectin. Glycans containing the Lewis x determinant (Le(x)) Gal beta 1-4[Fuc alpha 1-3]GlcNAc beta 1-3-R were significantly retarded in elution from high density LTA-Emphaze columns. The lectin also bound the fucosylated lacdiNAc trisaccharide GalNAc beta 1-4[Fuc alpha 1-3]GlcNAc. The lectin did not bind glycans containing either sialylLe(x) or VIM-2 determinants, nor did it bind the isomeric Le(x), Gal beta 1-3[Fuc alpha 1-4]GlcNAc-R. Although 2'-fucosyllactose Fuc alpha 1-2Gal beta 1-4Glc) was retarded in elution from the columns, larger glycans containing the H-antigen Fuc alpha 1-2Gal beta 1-3(4)GlcNAc-R interacted poorly with immobilized LTA. Our results demonstrate that immobilized LTA is effective in isolating glycans containing the Le(x) antigen and is useful in analyzing specific fucosylation of glycoconjugates.

  9. Angular MET sensor for precise azimuth determination

    NASA Astrophysics Data System (ADS)

    Zaitsev, Dmitry; Antonov, Alexander; Krishtop, Vladimir

    2016-12-01

    This paper describes using a MET-based low-noise angular motion sensor to precisely determine azimuth direction in a dynamic-scheme method of measuring Earth's rotation velocity vector. The scheme includes installing a sensor on a rotating platform so that it could scan a space and seek for the position of highest Earth's rotation vector projection on its axis. This method is very efficient provided a low-noise sensor is used. We take a low-cost angular sensor based on MET (molecular electronic transduction) technology. Sensors of this kind were originally developed for the seismic activity monitoring and are well-known for very good noise performance and high sensitivity. This approach, combined with use of special signal processing algorithms, allowed for reaching the accuracy of 0.07° for a measurement time of 200 seconds.

  10. Determination of fluorescence-labeled asparaginyl-oligosaccharide in glycoprotein by reversed-phase ultraperformance liquid chromatography with electrospray ionization time-of-flight mass spectrometry.

    PubMed

    Kurihara, Takamasa; Min, Jun Zhe; Toyo'oka, Toshimasa; Fukushima, Takeshi; Inagaki, Shinsuke

    2007-11-15

    Eight fluorescence reagents, i.e., DBD-F, NBD-F, DNS-Cl, NDA, PSC, FITC, Fmoc-Cl, and DMEQ-COCl, which are reactive to an amino functional group, were tested for the labeling of asparaginyl-oligosaccharides in a glycoprotein. Although the optimal reaction conditions and the fluorescence maximal wavelengths were different for each reagent, the highly sensitive fluorescence detection at the femtomole level of Disialo-Asn (a representative asparaginyl-oligosaccharide) was obtained from the labeling utilizing these reagents. Among them, PSC was the most reliable reagent in terms of detection sensitivity (approximately 3 fmol, signal-to-noise ratio of 5 (S/N = 5) on the chromatogram). However, the structural information could not be obtained from the fluorescence detection. Thus, the on-line determination of a real sample was carried out by UPLC-ESI-TOF-MS. The detection limit of the PSC-labeled Disialo-Asn by selected-ion chromatography was 58 fmol (S/N = 5). When the proposed procedure was applied to the determination of oligosaccharides in ovalbumin, 15 species of PSC-labeled oligosaccharides possessing Man, GlcNAc, and Gal units were identified from the UPLC-ESI-TOF-MS. The number of identified oligosaccharides was relatively greater than the method using Fmoc-Cl. Based on the ovalbumin results, the proposed labeling with PSC followed by UPLC-ESI-TOF-MS detection seems to be useful for the on-line asparaginyl-oligosaccharide analysis.

  11. Annotation and structural elucidation of bovine milk oligosaccharides and determination of novel fucosylated structures.

    PubMed

    Aldredge, Danielle L; Geronimo, Maria R; Hua, Serenus; Nwosu, Charles C; Lebrilla, Carlito B; Barile, Daniela

    2013-06-01

    Bovine milk oligosaccharides (BMOs) are recognized by the dairy and food industries, as well as by infant formula manufacturers, as novel, high-potential bioactive food ingredients. Recent studies revealed that bovine milk contains complex oligosaccharides structurally related to those previously thought to be present in only human milk. These BMOs are microbiotic modulators involved in important biological activities, including preventing pathogen binding to the intestinal epithelium and serving as nutrients for a selected class of beneficial bacteria. Only a small number of BMO structures are fully elucidated. To better understand the potential of BMOs as a class of biotherapeutics, their detailed structure analysis is needed. This study initiated the development of a structure library of BMOs and a comprehensive evaluation of structure-related specificity. The bovine milk glycome was profiled by high-performance mass spectrometry and advanced separation techniques to obtain a comprehensive catalog of BMOs, including several novel, lower abundant neutral and fucosylated oligosaccharides that are often overlooked during analysis. Structures were identified using isomer-specific tandem mass spectroscopy and targeted exoglycosidase digestions to produce a BMO library detailing retention time, accurate mass and structure to allow their rapid identification in future studies.

  12. Annotation and structural elucidation of bovine milk oligosaccharides and determination of novel fucosylated structures

    PubMed Central

    Aldredge, Danielle L; Geronimo, Maria R; Hua, Serenus; Nwosu, Charles C; Lebrilla, Carlito B; Barile, Daniela

    2013-01-01

    Bovine milk oligosaccharides (BMOs) are recognized by the dairy and food industries, as well as by infant formula manufacturers, as novel, high-potential bioactive food ingredients. Recent studies revealed that bovine milk contains complex oligosaccharides structurally related to those previously thought to be present in only human milk. These BMOs are microbiotic modulators involved in important biological activities, including preventing pathogen binding to the intestinal epithelium and serving as nutrients for a selected class of beneficial bacteria. Only a small number of BMO structures are fully elucidated. To better understand the potential of BMOs as a class of biotherapeutics, their detailed structure analysis is needed. This study initiated the development of a structure library of BMOs and a comprehensive evaluation of structure-related specificity. The bovine milk glycome was profiled by high-performance mass spectrometry and advanced separation techniques to obtain a comprehensive catalog of BMOs, including several novel, lower abundant neutral and fucosylated oligosaccharides that are often overlooked during analysis. Structures were identified using isomer-specific tandem mass spectroscopy and targeted exoglycosidase digestions to produce a BMO library detailing retention time, accurate mass and structure to allow their rapid identification in future studies. PMID:23436288

  13. Comprehensive profiles of human milk oligosaccharides yield highly sensitive and specific markers for determining secretor status in lactating mothers.

    PubMed

    Totten, Sarah M; Zivkovic, Angela M; Wu, Shuai; Ngyuen, UyenThao; Freeman, Samara L; Ruhaak, L Renee; Darboe, Momodou K; German, J Bruce; Prentice, Andrew M; Lebrilla, Carlito B

    2012-12-07

    Human milk oligosaccharides (HMOs), as an abundant and bioactive component of breast milk, work in many ways to promote the health of breast fed infants. The expression of HMOs has been shown to vary in accordance with Lewis blood type and secretor status, as women of different blood types differ in the expression of α1,2 fucosyltransferase (FUT2) and α1,3/4 fucosyltransferase (FUT3). In this study, HMOs were extracted from the milk of 60 women from The Gambia, Africa with various Lewis and secretor blood types. The HMOs were profiled using high resolution HPLC-Chip/TOF mass spectrometry. Notably, the amounts of fucosylation varied significantly between Le(a+b-) nonsecretors, Le(a-b+) and Le(a-b-) secretors, and Le(a-b-) nonsecretors. With higher frequency of expression of the recessive Lewis negative and nonsecretor phenotypes in West African populations, the HMO profiles of several milks from women of these phenotypes were examined, demonstrating decreased amounts of total oligosaccharide abundance and lower relative amounts of fucosylation. Also in this study, four specific fucosylated structures (2'FL, LNFP I, LDFT, and LNDFH I) were determined to be specific and sensitive glycan markers for rapidly determining secretor status without the need for serological testing.

  14. Effect of sucrose concentration on the composition of enzymatically synthesized short-chain fructo-oligosaccharides as determined by FTIR and multivariate analysis.

    PubMed

    Romano, Nelson; Santos, Mauricio; Mobili, Pablo; Vega, Roberto; Gómez-Zavaglia, Andrea

    2016-07-01

    Fructo-oligosaccharides (FOS) are mixtures of oligosaccharides composed of fructose and glucose units. As their composition is determined by the synthesis conditions, the goals of this work were: (a) to engineer FOS of different composition by adjusting the sucrose concentration used as initial substrate; (b) to define partial least square (PLS) based-models to quantify all the sugars present in the reaction medium directly from the FTIR spectra. The yield of each reaction was calculated as the percentage of initial sucrose converted to each oligosaccharide, as monitored by HPLC. In parallel, the reactions were followed by FTIR. Six different PLS models aiming to determine the concentration of each carbohydrate present in the reaction medium were calibrated and independently validated. The means of predicted values fitted well to those obtained by HPLC. Determining FOS composition directly from the FTIR spectra represents a useful tool to monitor enzymatic synthesis, with strong impact at both an academic and an industrial level.

  15. GRAS NRT Precise Orbit Determination: Operational Experience

    NASA Technical Reports Server (NTRS)

    MartinezFadrique, Francisco M.; Mate, Alberto Agueda; Rodriquez-Portugal, Francisco Sancho

    2007-01-01

    EUMETSAT launched the meteorological satellite MetOp-A in October 2006; it is the first of the three satellites that constitute the EUMETSAT Polar System (EPS) space segment. This satellite carries a challenging and innovative instrument, the GNSS Receiver for Atmospheric Sounding (GRAS). The goal of the GRAS instrument is to support the production of atmospheric profiles of temperature and humidity with high accuracy, in an operational context, based on the bending of the GPS signals traversing the atmosphere during the so-called occultation periods. One of the key aspects associated to the data processing of the GRAS instrument is the necessity to describe the satellite motion and GPS receiver clock behaviour with high accuracy and within very strict timeliness limitations. In addition to these severe requirements, the GRAS Product Processing Facility (PPF) must be integrated in the EPS core ground segment, which introduces additional complexity from the data integration and operational procedure points of view. This paper sets out the rationale for algorithm selection and the conclusions from operational experience. It describes in detail the rationale and conclusions derived from the selection and implementation of the algorithms leading to the final orbit determination requirements (0.1 mm/s in velocity and 1 ns in receiver clock error at 1 Hz). Then it describes the operational approach and extracts the ideas and conclusions derived from the operational experience.

  16. Estimating maneuvers for precise relative orbit determination using GPS

    NASA Astrophysics Data System (ADS)

    Allende-Alba, Gerardo; Montenbruck, Oliver; Ardaens, Jean-Sébastien; Wermuth, Martin; Hugentobler, Urs

    2017-01-01

    Precise relative orbit determination is an essential element for the generation of science products from distributed instrumentation of formation flying satellites in low Earth orbit. According to the mission profile, the required formation is typically maintained and/or controlled by executing maneuvers. In order to generate consistent and precise orbit products, a strategy for maneuver handling is mandatory in order to avoid discontinuities or precision degradation before, after and during maneuver execution. Precise orbit determination offers the possibility of maneuver estimation in an adjustment of single-satellite trajectories using GPS measurements. However, a consistent formulation of a precise relative orbit determination scheme requires the implementation of a maneuver estimation strategy which can be used, in addition, to improve the precision of maneuver estimates by drawing upon the use of differential GPS measurements. The present study introduces a method for precise relative orbit determination based on a reduced-dynamic batch processing of differential GPS pseudorange and carrier phase measurements, which includes maneuver estimation as part of the relative orbit adjustment. The proposed method has been validated using flight data from space missions with different rates of maneuvering activity, including the GRACE, TanDEM-X and PRISMA missions. The results show the feasibility of obtaining precise relative orbits without degradation in the vicinity of maneuvers as well as improved maneuver estimates that can be used for better maneuver planning in flight dynamics operations.

  17. Improved DORIS accuracy for precise orbit determination and geodesy

    NASA Technical Reports Server (NTRS)

    Willis, Pascal; Jayles, Christian; Tavernier, Gilles

    2004-01-01

    In 2001 and 2002, 3 more DORIS satellites were launched. Since then, all DORIS results have been significantly improved. For precise orbit determination, 20 cm are now available in real-time with DIODE and 1.5 to 2 cm in post-processing. For geodesy, 1 cm precision can now be achieved regularly every week, making now DORIS an active part of a Global Observing System for Geodesy through the IDS.

  18. Mixed-Linkage Glucan Oligosaccharides Produced by Automated Glycan Assembly Serve as Tools To Determine the Substrate Specificity of Lichenase.

    PubMed

    Dallabernardina, Pietro; Schuhmacher, Frank; Seeberger, Peter H; Pfrengle, Fabian

    2017-03-02

    The mixed-linkage (1→3),(1→4)-d-glucan (MLG) specific glycosyl hydrolase lichenase is an important biochemical tool for the structural characterization of MLGs. It holds potential for application in the brewery, animal feed, and biofuel industries. Several defined MLG oligosaccharides obtained by automated glycan assembly are used to analyze the substrate specificities of Bacillus subtilis lichenase. Two glucose building blocks (BBs), equipped with a temporary fluorenylmethyloxycarbonyl chloride (Fmoc) protecting group in the C-3 or C-4 position, served to assemble different oligosaccharides by using an automated oligosaccharide synthesizer. Light-induced cleavage of the glycan products from the solid support followed by global deprotection provided seven MLG oligosaccharides of different length and connectivity. After incubation of the MLG oligosaccharides with lichenase, the digestion products were analyzed by HPLC-MS. These digestion experiments provided insights into the enzyme's active site that is in line with other recent evidence suggesting that the substrate specificity of lichenases has to be reconsidered. These results demonstrate that synthetic MLG oligosaccharides are useful tools to analyze mixed-linkage β-glucanases.

  19. Linkage determination of linear oligosaccharides by MS(n) (n > 2) collision-induced dissociation of Z₁ ions in the negative ion mode.

    PubMed

    Konda, Chiharu; Bendiak, Brad; Xia, Yu

    2014-02-01

    Obtaining unambiguous linkage information between sugars in oligosaccharides is an important step in their detailed structural analysis. An approach is described that provides greater confidence in linkage determination for linear oligosaccharides based on multiple-stage tandem mass spectrometry (MS(n), n >2) and collision-induced dissociation (CID) of Z1 ions in the negative ion mode. Under low energy CID conditions, disaccharides (18)O-labeled on the reducing carbonyl group gave rise to Z1 product ions (m/z 163) derived from the reducing sugar, which could be mass-discriminated from other possible structural isomers having m/z 161. MS(3) CID of these m/z 163 ions showed distinct fragmentation fingerprints corresponding to the linkage types and largely unaffected by sugar unit identities or their anomeric configurations. This unique property allowed standard CID spectra of Z1 ions to be generated from a small set of disaccharide samples that were representative of many other possible isomeric structures. With the use of MS(n) CID (n = 3 - 5), model linear oligosaccharides were dissociated into overlapping disaccharide structures, which were subsequently fragmented to form their corresponding Z1 ions. CID data of these Z1 ions were collected and compared with the standard database of Z1 ion CID using spectra similarity scores for linkage determination. As the proof-of-principle tests demonstrated, we achieved correct determination of individual linkage types along with their locations within two trisaccharides and a pentasaccharide.

  20. Selection of Wavelengths for Optimum Precision in Simultaneous Spectrophotometric Determinations.

    ERIC Educational Resources Information Center

    DiTusa, Michael R.; Schilt, Alfred A.

    1985-01-01

    Although many textbooks include a description of simultaneous determinations employing absorption spectrophotometry and treat the mathematics necessary for analytical quantitations, treatment of analytical wavelength selection has been mostly qualitative. Therefore, a general method for selecting wavelengths for optimum precision in simultaneous…

  1. Determination of LAGEOS satellite's precise orbits and residual analysis

    NASA Astrophysics Data System (ADS)

    Feng, C. G.; Zhang, F. P.; Zhu, Y. L.

    2003-02-01

    Determination of LAGEOS satellite's precise orbits based on an analysis residual error of SLR data are introduced in detail. The method analyzing the data of satellite laser ranging (SLR)?the dynamical models used and the number of parameters estimated should be changed with the different purposes. The schemes were compared with each other and were analyzed with the number of parameters estimated and the residual errors in detail. The determination of precise orbits is the key of these. To acquire a precise orbit, the models determining the EOP were modified. The scheme being used by SHAO was selected from the several schemes. In this paper, the results of LAGEOS satellite's precise orbits from Dec. 31, 1998 to Jun. 29, 2001 are set out only. The results show that the root-mean square value of the residuals are less than 2cm. SHAO has begun the service of LAGEOS-1/LAGEOS-2 quick-look residual analysis since Oct.1, 1999. The results can be find on the intent address: http://center.shao.ac.cn/APSG/result

  2. Adaptation of the AOAC 2011.25 integrated total dietary fiber assay to determine the dietary fiber and oligosaccharide content of dry edible beans.

    PubMed

    Kleintop, Adrienne E; Echeverria, Dimas; Brick, Leslie A; Thompson, Henry J; Brick, Mark A

    2013-10-09

    Dietary fiber (DF) has important health benefits in the human diet. Developing dry edible bean (Phaseolus vulgaris L.) cultivars with improved DF and reduced nondigestible oligosaccharide content is an important goal for dry bean breeders to increase consumer acceptance. To determine if genetic variation exists among dry bean cultivars for DF, two populations of diverse dry bean cultivars/lines that represent two centers of dry bean domestication were evaluated for dietary fiber using the Integrated Total Dietary Fiber Assay (AOAC 2011.25). This assay was adapted to measure water insoluble dietary fiber, water soluble dietary fiber, oligosaccharides raffinose and stachyose, and the calculated total dietary fiber (TDF) content of cooked dry bean seed. The AOAC 2011.25 protocol was modified by using a quick, simple, and sensitive high-performance liquid chromatography method paired with an electrochemical detection method to separate and quantify specific oligosaccharides, and using duplicate samples as replicates to generate statistical information. The TDF of dry bean entries ranged from 20.0 to 27.0% in population I and from 20.6 to 25.7% in population II. Total oligosaccharides ranged from 2.56 to 4.65% in population I and from 2.36 to 3.84% in population II. The results suggest that significant genetic variation exists among dry bean cultivars/lines to allow for genetic selection for improved DF content in dry beans and that the modifications to the AOAC 2011.25 method were suitable for estimating DF in cooked dry edible beans.

  3. Precise determination of the helical repeat of tobacco mosaic virus

    SciTech Connect

    Kendall, Amy; McDonald, Michele; Stubbs, Gerald

    2007-12-05

    Tobacco mosaic virus (TMV) is widely used as a distance standard in electron microscopy, fiber diffraction, and other imaging techniques. The dimension used as a reference is the pitch of the viral helix, 23 A. This distance, however, has never been measured with any great degree of precision. The helical pitch of TMV has been determined to be 22.92 {+-} 0.03 A by X-ray fiber diffraction methods using highly collimated synchrotron radiation.

  4. Precise Determination of the Helical Repeat of Tobacco Mosaic Virus

    SciTech Connect

    Kendall, A.; McDonald, M.; Stubbs, G.

    2009-06-01

    Tobacco mosaic virus (TMV) is widely used as a distance standard in electron microscopy, fiber diffraction, and other imaging techniques. The dimension used as a reference is the pitch of the viral helix, 23 {angstrom}. This distance, however, has never been measured with any great degree of precision. The helical pitch of TMV has been determined to be 22.92 {+-}0.03 {angstrom} by X-ray fiber diffraction methods using highly collimated synchrotron radiation.

  5. Relative Abundance of Oligosaccharides in Candida Species as Determined by Fluorophore-Assisted Carbohydrate Electrophoresis

    PubMed Central

    Goins, Tresa L.; Cutler, Jim E.

    2000-01-01

    Fluorophore-assisted carbohydrate electrophoresis (FACE) is a straightforward, sensitive method for determining the presence and relative abundance of individual oligomannosyl residues in Candida mannoprotein, the major antigenic determinant located on the outer surface of the yeast cell wall. The single terminal aldehydes of oligomannosyl residues released by hydrolysis were tagged with the charged fluorophore 8-aminonaphthalene-1,3,6-trisulfonate (ANTS) and separated with high resolution on the basis of size by polyacrylamide gel electrophoresis. ANTS fluorescence labeling was not biased by oligomannoside length; therefore, band fluorescence intensity was directly related to the relative abundance of individual oligomannoside moieties in heterogeneous samples. FACE analysis revealed the major oligomannosides released by acid hydrolysis and β-elimination of Fehling-precipitated mannan from Candida albicans, which were the same as those previously reported in studies based on mass and nuclear magnetic spectroscopic analysis. FACE was also amenable to the analysis of samples obtained by direct hydrolysis of whole yeast cells. Whole-cell acid hydrolysis and whole-cell β-elimination of two isolates each of C. albicans, C. glabrata, C. krusei, C. lusitaniae, C. parapsilosis, C. rugosa, C. stellatoidea, and C. tropicalis resulted in oligomannoside gel banding patterns that were species and strain specific for the 16 isolates surveyed. Whereas some bands were specific for an individual isolate or species, other bands were shared by two or three species in various groupings. Differences in the mannoprotein composition of C. albicans A9 and four spontaneous cell surface mutants were also detected. Mannan “fingerprints,” or banding pattern profiles, derived from the electrophoretic mobilities of individual bands relative to the migration of acid-hydrolyzed dextran (relative migration index) yielded profiles characteristic of individual isolates not revealed by

  6. Hexuronic acid stereochemistry determination in chondroitin sulfate glycosaminoglycan oligosaccharides by electron detachment dissociation.

    PubMed

    Leach, Franklin E; Ly, Mellisa; Laremore, Tatiana N; Wolff, Jeremy J; Perlow, Jacob; Linhardt, Robert J; Amster, I Jonathan

    2012-09-01

    Electron detachment dissociation (EDD) has previously provided stereo-specific product ions that allow for the assignment of the acidic C-5stereochemistry in heparan sulfate glycosaminoglycans (GAGs), but application of the same methodology to an epimer pair in the chondroitin sulfate glycoform class does not provide the same result. A series of experiments have been conducted in which glycosaminoglycan precursor ions are independently activated by electron detachment dissociation (EDD), electron induced dissociation (EID), and negative electron transfer dissociation (NETD) to assign the stereochemistry in chondroitin sulfate (CS) epimers and investigate the mechanisms for product ion formation during EDD in CS glycoforms. This approach allows for the assignment of electronic excitation products formed by EID and detachment products to radical pathways in NETD, both of which occur simultaneously during EDD. The uronic acid stereochemistry in electron detachment spectra produces intensity differences when assigned glycosidic and cross-ring cleavages are compared. The variations in the intensities of the doubly deprotonated (0,2)X(3) and Y(3) ions have been shown to be indicative of CS-A/DS composition during the CID of binary mixtures. These ions can provide insight into the uronic acid composition of binary mixtures in EDD, but the relative abundances, although reproducible, are low compared with those in a CID spectrum acquired on an ion trap. The application of principal component analysis (PCA) presents a multivariate approach to determining the uronic acid stereochemistry spectra of these GAGs by taking advantage of the reproducible peak distributions produced by electron detachment.

  7. Precise Atomic Mass Difference Determinations for Thallium and Lead

    NASA Astrophysics Data System (ADS)

    Sidky, Mohamed Hussien

    Atomic mass differences are usually determined by a variation of a technique known as "peak matching". Two techniques have been developed and applied to the Manitoba II spectrometer: visual null peak matching and computer -assisted peak matching. For the computer matching technique, peaks may be located by using either a centroid or a least squares method. In this work, an improved procedure is established for the least squares method. With this new procedure the accuracy and the precision of a calculated mass difference is significantly improved. The Manitoba II mass spectrometer has been used to measure the spacings of 4 doublets in the mass spectra of TlCl_{rm x} and PbCl_{rm y}. The average precision of the new mass differences (least squares method computer runs) surpasses that of our earlier work (centroid method computer runs and visual runs) by a factor of about 1.3. This program of measurements was aimed at determining the ^{205}Pb - ^{205}Tl atomic mass difference, which is used to determine the threshold energy of the neutrino capture reaction: nu + ^{205}Tl to ^{205}Pb + e. It has been suggested that this reaction may provide a good mechanism on which a solar neutrino detector may be based (Freedman, 1976). A new value for the ^ {205}Pb- ^{205} Tl mass difference is calculated by combining our new data with other precise data obtained from (n, gamma) reactions and beta decays. Our value (51.87 +/- 0.84 keV) agrees with accepted values and substantially improves the precision of this mass difference.

  8. Strategies for high-precision Global Positioning System orbit determination

    NASA Technical Reports Server (NTRS)

    Lichten, Stephen M.; Border, James S.

    1987-01-01

    Various strategies for the high-precision orbit determination of the GPS satellites are explored using data from the 1985 GPS field test. Several refinements to the orbit determination strategies were found to be crucial for achieving high levels of repeatability and accuracy. These include the fine tuning of the GPS solar radiation coefficients and the ground station zenith tropospheric delays. Multiday arcs of 3-6 days provided better orbits and baselines than the 8-hr arcs from single-day passes. Highest-quality orbits and baselines were obtained with combined carrier phase and pseudorange solutions.

  9. Precise orbit determination for the GOCE satellite using GPS

    NASA Astrophysics Data System (ADS)

    Bock, H.; Jäggi, A.; Švehla, D.; Beutler, G.; Hugentobler, U.; Visser, P.

    Apart from the gradiometer as the core instrument, the first ESA Earth Explorer Core Mission GOCE (Gravity field and steady-state Ocean Circulation Explorer) will carry a 12-channel GPS receiver dedicated for precise orbit determination (POD) of the satellite. The EGG-C (European GOCE Gravity-Consortium), led by the Technical University in Munich, is building the GOCE HPF (High-level Processing Facility) dedicated to the Level 1b to Level 2 data processing. One of the tasks of this facility is the computation of the Precise Science Orbit (PSO) for GOCE. The PSO includes a reduced-dynamic and a kinematic orbit solution. The baseline for the PSO is a zero-difference procedure using GPS satellite orbits, clocks, and Earth Rotation Parameters (ERPs) from CODE (Center for Orbit Determination in Europe), one of the IGS (International GNSS Service) Analysis Centers. The scheme for reduced-dynamic and kinematic orbit determination is based on experiences gained from CHAMP and GRACE POD and is realized in one processing flow. Particular emphasis is put on maximum consistency in the analysis of day boundary overlapping orbital arcs, as well as on the higher data sampling rate with respect to CHAMP and GRACE and on differences originating from different GPS antenna configurations. We focus on the description of the procedure used for the two different orbit determinations and on the validation of the procedure using real data from the two GRACE satellites as well as simulated GOCE data.

  10. Precise Orbit Determination for the GOCE Satellite Using GPS

    NASA Astrophysics Data System (ADS)

    Bock, H.; Jäggi, A.; Svehla, D.; Beutler, G.; Hugentobler, U.; Visser, P.

    Apart from the gradiometer as the core instrument the first ESA Earth Explorer Core mission GOCE Gravity field and steady-state Ocean Circulation Explorer carries a 12-channel GPS receiver dedicated for precise orbit determination POD of the satellite The EGG-C European GOCE Gravity-Consortium led by the Technical University in Munich is building the GOCE HPF High-level Processing Facility dedicated to the Level 1b to Level 2 data processing One of the tasks of this facility is the computation of the Precise Science Orbit PSO for GOCE The PSO includes a reduced-dynamic and a kinematic orbit solution The baseline for the PSO is a zero difference procedure using GPS satellite orbits clocks and Earth Rotation Parameters ERPs from CODE Center for Orbit Determination in Europe one of the IGS International GNSS Service Analysis Centers The scheme for reduced-dynamic and kinematic orbit determination is based on experiences gained from CHAMP and GRACE POD and is realized in one processing flow Particular emphasis is put on maximum consistency in the analysis of day-boundary overlapping orbital arcs as well as on the higher data sampling rate and on differences originating from different GPS antenna configuration We focus on the description of the procedure used for the two different orbit determinations and on the validation of the procedure using real data from the two GRACE satellites as well as simulated GOCE data

  11. Advances in precision orbit determination of GRACE satellites

    NASA Astrophysics Data System (ADS)

    Bettadpur, Srinivas; Save, Himanshu; Kang, Zhigui

    The twin Gravity Recovery And Climate Experiment (GRACE) satellites carry a complete suite of instrumentation essential for precision orbit determination (POD). Dense, continuous and global tracking is provided by the Global Positioning System receivers. The satellite orientation is measured using two star cameras. High precision measurements of non-gravitational accel-erations are provided by accelerometers. Satellite laser ranging (SLR) retroreflectors are used for collecting data for POD validation. Additional validation is provided by the highly precise K-Band ranging system measuring distance changes between the twin GRACE satellites. This paper presents the status of POD for GRACE satellites. The POD quality will be vali-dated using the SLR and K-Band ranging data. The POD quality improvement from upgraded modeling of the GPS observations, including the transition to the new IGS05 standards, will be discussed. In addition, the contributions from improvements in the gravity field modeling -partly arising out of GRACE science results -will be discussed. The aspects of these improve-ments that are applicable for the POD of other low-Earth orbiting satellites will be discussed as well.

  12. Precise attitude determination of defunct satellite laser ranging tragets

    NASA Astrophysics Data System (ADS)

    Pittet, Jean-Noel; Schildknecht, Thomas; Silha, Jiri

    2016-07-01

    The Satellite Laser Ranging (SLR) technology is used to determine the dynamics of objects equipped with so-called retro-reflectors or retro-reflector arrays (RRA). This type of measurement allows to range to the spacecraft with very high precision, which leads to determination of very accurate orbits. Non-active spacecraft, which are not any more attitude controlled, tend to start to spin or tumble under influence of the external and internal torques. Such a spinning can be around one constant axis of rotation or it can be more complex, when also precession and nutation motions are present. The rotation of the RRA around the spacecraft's centre of mass can create both a oscillation pattern of laser range signal and a periodic signal interruption when the RRA is hidden behind the satellite. In our work we will demonstrate how the SLR ranging technique to cooperative targets can be used to determine precisely their attitude state. The processing of the obtained data will be discussed, as well as the attitude determination based on parameters estimation. Continuous SLR measurements to one target can allow to accurately monitor attitude change over time which can be further used for the future attitude modelling. We will show our solutions of the attitude states determined for the non-active ESA satellite ENVISAT based on measurements acquired during year 2013-2015 by Zimmerwald SLR station, Switzerland. The angular momentum shows a stable behaviour with respect to the orbital plane but is not aligned with orbital momentum. The determination of the inertial rotation over time, shows it evolving between 130 to 190 seconds within two year. Parameter estimation also bring a strong indication of a retrograde rotation. Results on other former satellites in low and medium Earth orbit such as TOPEX/Poseidon or GLONASS type will be also presented.

  13. Precise Orbit Determination of Low Earth Satellites at AIUB

    NASA Astrophysics Data System (ADS)

    Jaggi, A.; Bock, H.; Thaller, D.; Dach, R.; Beutler, G.; Prange, L.; Meyer, U.

    2010-12-01

    Many low Earth orbiting (LEO) satellites are nowadays equipped with on-board receivers to collect the observations from Global Navigation Satellite Systems (GNSS), such as the Global Positioning System (GPS), or with retro-reflectors for Satellite Laser Ranging (SLR). At the Astronomical Institute of the University of Bern (AIUB) LEO precise orbit determination (POD) using either GPS or SLR data is performed for satellites at very different altitudes. The classical numerical integration techniques used for dynamic orbit determination of LEO satellites at high altitudes are extended by pseudo-stochastic orbit modeling techniques for satellites at low altitudes to efficiently cope with force model deficiencies. Accuracies of a few centimeters are achieved by pseudo-stochastic orbit modeling, e.g., for the Gravity field and steady-state Ocean Circulation Explorer (GOCE).

  14. Can an ancestral condition for milk oligosaccharides be determined? Evidence from the Tasmanian echidna (Tachyglossus aculeatus setosus).

    PubMed

    Oftedal, Olav T; Nicol, Stewart C; Davies, Noel W; Sekii, Nobuhiro; Taufik, Epi; Fukuda, Kenji; Saito, Tadao; Urashima, Tadasu

    2014-09-01

    The monotreme pattern of egg-incubation followed by extended lactation represents the ancestral mammalian reproductive condition, suggesting that monotreme milk may include saccharides of an ancestral type. Saccharides were characterized from milk of the Tasmanian echidna Tachyglossus aculeatus setosus. Oligosaccharides in pooled milk from late lactation were purified by gel filtration and high-performance liquid chromatography using a porous graphitized carbon column and characterized by (1)H NMR spectroscopy; oligosaccharides in smaller samples from early and mid-lactation were separated by ultra-performance liquid chromatography and characterized by negative electrospray ionization mass spectrometry (ESI-MS) and tandem collision mass spectroscopy (MS/MS) product ion patterns. Eight saccharides were identified by (1)H NMR: lactose, 2'-fucosyllactose, difucosyllactose (DFL), B-tetrasaccharide, B-pentasaccharide, lacto-N-fucopentaose III (LNFP3), 4-O-acetyl-3'-sialyllactose [Neu4,5Ac(α2-3)Gal(β1-4)Glc] and 4-O-acetyl-3'-sialyl-3-fucosyllactose [Neu4,5Ac(α2-3)Gal(β1-4)[Fuc(α1-3)]Glc]. Six of these (all except DFL and LNFP3) were present in early and mid-lactation per ESI-MS, although some at trace levels. Four additional oligosaccharides examined by ESI-MS and MS/MS are proposed to be 3'-sialyllactose [Neu5Ac(α2-3)Gal(β1-4)Glc], di-O-acetyl-3'-sialyllactose [Neu4,5,UAc3(α2-3)Gal(β1-4)Glc where U = 7, 8 or 9], 4-O-acetyl-3'-sialyllactose sulfate [Neu4,5Ac(α2-3)Gal(β1-4)GlcS, where position of the sulfate (S) is unknown] and an unidentified 800 Da oligosaccharide containing a 4-O-acetyl-3'-sialyllactose core. 4-O-acetyl-3'-sialyllactose was the predominant saccharide at all lactation stages. 4-O-Acetylation is known to protect sialyllactose from bacterial sialidases and may be critical to prevent microbial degradation on the mammary areolae and/or in the hatchling digestive tract so that sialyllactose can be available for enterocyte uptake. The ability to

  15. Precision orbit determination for the GEOSAT exact repeat mission

    NASA Astrophysics Data System (ADS)

    Smith, J. C.; Ries, J. C.; Shum, C. K.; Schutz, B. E.; Tapley, B. D.

    The Navy's Geodetic Satellite (GEOSAT) was launched on March 12, 1985, carrying a single-frequency microwave altimeter which measures the height of the satellite above the ocean surface to a precision of a few centimeters. The GEOSAT Exact Repeat Mission (ERM), which was initiated in November of 1986, placed the spacecraft in an exact 17 day repeat orbit. The Geophysical Data Records (GDR) for the ERM are available to the scientific community. GEOSAT is tracked by the Navy's OPNET and the Defense Mapping Agency's TRANET doppler tracking systems. The GDR orbits are computed using the OPNET tracking data and have an rms radial accuracy of one to two meters. The initial eighty days of the TRANET data during the ERM were made available for the assessment of the TRANET tracking system to perform precision orbit determination for the Topex/Poseidon Mission. This data was used to compute GEOSAT orbits using an improved gravity model which has been developed as part of the Topex gravity model improvement effort. Accuracy of the orbit was evaluated using altimeter crossover data. For a continuous 17 day GEOSAT orbit, the global crossover rms is at the 35 cm level, which suggests a radial orbit accuracy also on the order of 35 cm.

  16. Improving GLONASS Precise Orbit Determination through Data Connection

    PubMed Central

    Liu, Yang; Ge, Maorong; Shi, Chuang; Lou, Yidong; Wickert, Jens; Schuh, Harald

    2015-01-01

    In order to improve the precision of GLONASS orbits, this paper presents a method to connect the data segments of a single station-satellite pair to increase the observation continuity and, consequently, the strength of the precise orbit determination (POD) solution. In this method, for each GLONASS station-satellite pair, the wide-lane ambiguities derived from the Melbourne–Wübbena combination are statistically tested and corrected for phase integer offsets and then the same is carried out for the narrow-lane ambiguities calculated from the POD solution. An experimental validation was carried out using one-month GNSS data of a global network with 175 IGS stations. The result shows that, on average, 27.1% of the GLONASS station-satellite pairs with multiple data segments could be connected to a single long observation arc and, thus, only one ambiguity parameter was estimated. Using the connected data, the GLONASS orbit overlapping RMS at the day boundaries could be reduced by 19.2% in ideal cases with an averaged reduction of about 6.3%. PMID:26633414

  17. Improving GLONASS Precise Orbit Determination through Data Connection.

    PubMed

    Liu, Yang; Ge, Maorong; Shi, Chuang; Lou, Yidong; Wickert, Jens; Schuh, Harald

    2015-12-02

    In order to improve the precision of GLONASS orbits, this paper presents a method to connect the data segments of a single station-satellite pair to increase the observation continuity and, consequently, the strength of the precise orbit determination (POD) solution. In this method, for each GLONASS station-satellite pair, the wide-lane ambiguities derived from the Melbourne-Wübbena combination are statistically tested and corrected for phase integer offsets and then the same is carried out for the narrow-lane ambiguities calculated from the POD solution. An experimental validation was carried out using one-month GNSS data of a global network with 175 IGS stations. The result shows that, on average, 27.1% of the GLONASS station-satellite pairs with multiple data segments could be connected to a single long observation arc and, thus, only one ambiguity parameter was estimated. Using the connected data, the GLONASS orbit overlapping RMS at the day boundaries could be reduced by 19.2% in ideal cases with an averaged reduction of about 6.3%.

  18. Precision orbit determination for the Geosat Exact Repeat Mission

    NASA Technical Reports Server (NTRS)

    Shum, C. K.; Yuan, D. N.; Ries, J. C.; Smith, J. C.; Schutz, B. E.

    1990-01-01

    Precise ephemerides have been determined for the U.S. Navy Geosat Exact Repeat Mission (ERM) using an improved gravity-field model, PTGF-4A (Shum et al. 1989). The Geosat orbits were computed in a terrestrial reference system which is tied to the reference system defined by satellite laser ranging (SLR) to Lageos through a survey between the Tranet Doppler receiver and the SLR system located at Wettzell, FRG. The remaining Doppler tracking station coordinates were estimated simultaneously with the geopotential in the PTGF-4A solution. In this analysis, three continuous 17-day Geosat orbits, which were computed using the 46-station Tranet data and global altimeter crossover data, have a crossover residual rms of 20 cm, indicating that the Geosat radial orbit error is of the order of 20 cm. The orbits computed based on data collected by a 7-station OPNET tracking network and crossover data have the same level of accuracy.

  19. Precision orbit determination for the Geosat Exact Repeat Mission

    NASA Astrophysics Data System (ADS)

    Shum, C. K.; Yuan, D. N.; Ries, J. C.; Smith, J. C.; Schutz, B. E.

    1990-03-01

    Precise ephemerides have been determined for the U.S. Navy Geosat Exact Repeat Mission (ERM) using an improved gravity-field model, PTGF-4A (Shum et al. 1989). The Geosat orbits were computed in a terrestrial reference system which is tied to the reference system defined by satellite laser ranging (SLR) to Lageos through a survey between the Tranet Doppler receiver and the SLR system located at Wettzell, FRG. The remaining Doppler tracking station coordinates were estimated simultaneously with the geopotential in the PTGF-4A solution. In this analysis, three continuous 17-day Geosat orbits, which were computed using the 46-station Tranet data and global altimeter crossover data, have a crossover residual rms of 20 cm, indicating that the Geosat radial orbit error is of the order of 20 cm. The orbits computed based on data collected by a 7-station OPNET tracking network and crossover data have the same level of accuracy.

  20. Precision Determination of the D{sup 0} Mass

    SciTech Connect

    Cawlfield, C.; Eisenstein, B. I.; Karliner, I.; Kim, D.; Lowrey, N.; Naik, P.; Selen, M.; White, E. J.; Wiss, J.; Mitchell, R. E.; Shepherd, M. R.; Besson, D.; Pedlar, T. K.; Cronin-Hennessy, D.; Gao, K. Y.; Hietala, J.; Kubota, Y.; Klein, T.; Lang, B. W.; Poling, R.

    2007-03-02

    A precision measurement of the D{sup 0} meson mass has been made using {approx}281 pb{sup -1} of e{sup +}e{sup -} annihilation data taken with the CLEO-c detector at the {psi}(3770) resonance. The exclusive decay D{sup 0}{yields}K{sub S}{phi} has been used to obtain M(D{sup 0})=1864.847{+-}0.150(stat){+-}0.095(syst) MeV. This corresponds to M(D{sup 0}D*{sup 0})=3871.81{+-}0.36 MeV, and leads to a well-constrained determination of the binding energy of the proposed D{sup 0}D*{sup 0} molecule X(3872), as E{sub b}=0.6{+-}0.6 MeV.

  1. Simple column-switching ion chromatography method for determining eight monosaccharides and oligosaccharides in honeydew and nectar.

    PubMed

    Ni, Chengzhu; Zhu, Binhe; Wang, Nani; Wang, Muhua; Chen, Suqing; Zhang, Jiajie; Zhu, Yan

    2016-03-01

    Honeydew is excreted by aphids as a sweet waste and nectar is floral honey. Honeydew and nectar are complicated samples which consist of various sugars and amino acids. In this work, a simple ion chromatography with column-switching method was developed for the simultaneous analysis of 8 monosaccharides and oligosaccharides in honeydew and nectar. A reversed-phase column was used as a pretreatment column to eliminate organics on-line and sugars were eluted from a collection loop to analytical column by using column-switching technique. This method showed good linearity (r⩾0.9994) and afforded low limits of detection ranging from 1.55 to 10.17μgL(-1) for all the analytes. Recoveries ranged from 95% to 105% and repeatability results were acceptable with relative standard deviation of less than 3.21% (n=6). This method was successfully applied to quantification of these sugars in honeydew and nectar. These results showed honeydew had much more oligosaccharides than nectar.

  2. Precise Orbit Determination of the GOCE Re-Entry Phase

    NASA Astrophysics Data System (ADS)

    Gini, Francesco; Otten, Michiel; Springer, Tim; Enderle, Werner; Lemmens, Stijn; Flohrer, Tim

    2015-03-01

    During the last days of the GOCE mission, after the GOCE spacecraft ran out of fuel, it slowly decayed before finally re-entering the atmosphere on the 11th November 2013. As an integrated part of the AOCS, GOCE carried a GPS receiver that was in operations during the re-entry phase. This feature provided a unique opportunity for Precise Orbit Determination (POD) analysis. As part of the activities carried out by the Navigation Support Office (HSO-GN) at ESOC, precise ephemerides of the GOCE satellite have been reconstructed for the entire re-entry phase based on the available GPS observations of the onboard LAGRANGE receiver. All the data available from the moment the thruster was switched off on the 21st of October 2013 to the last available telemetry downlink on the 10th November 2013 have been processed, for a total of 21 daily arcs. For this period a dedicated processing sequence has been defined and implemented within the ESA/ESOC NAvigation Package for Earth Observation Satellites (NAPEOS) software. The computed results show a post-fit RMS of the GPS undifferenced carrier phase residuals (ionospheric-free linear combination) between 6 and 14 mm for the first 16 days which then progressively increases up to about 80 mm for the last available days. An orbit comparison with the Precise Science Orbits (PSO) generated at the Astronomical Institute of the University of Bern (AIUB, Bern, Switzerland) shows an average difference around 9 cm for the first 8 daily arcs and progressively increasing up to 17 cm for the following days. During this reentry phase (21st of October - 10th November 2013) a substantial drop in the GOCE altitude is observed, starting from about 230 km to 130 km where the last GPS measurements were taken. During this orbital decay an increment of a factor of 100 in the aerodynamic acceleration profile is observed. In order to limit the mis-modelling of the non-gravitational forces (radiation pressure and aerodynamic effects) the newly developed

  3. Improving integer ambiguity resolution for GLONASS precise orbit determination

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Ge, Maorong; Shi, Chuang; Lou, Yidong; Wickert, Jens; Schuh, Harald

    2016-08-01

    The frequency division multiple access adopted in present GLONASS introduces inter-frequency bias (IFB) at the receiver-end both in code and phase observables, which makes GLONASS ambiguity resolution rather difficult or even not available, especially for long baselines up to several thousand kilometers. This is one of the major reasons that GLONASS could hardly reach the orbit precision of GPS, both in terms of consistency among individual International GNSS Service (IGS) analysis centers and discontinuity at the overlapping day boundaries. Based on the fact that the GLONASS phase IFB is similar on L1 and L2 bands in unit of length and is a linear function of the frequency number, several approaches have been developed to estimate and calibrate the IFB for integer ambiguity resolution. However, they are only for short and medium baselines. In this study, a new ambiguity resolution approach is developed for GLONASS global networks. In the approach, the phase ambiguities in the ionosphere-free linear combination are directly transformed with a wavelength of about 5.3 cm, according to the special frequency relationship of GLONASS L1 and L2 signals. After such transformation, the phase IFB rate can be estimated and corrected precisely and then the corresponding double-differenced ambiguities can be directly fixed to integers even for baselines up to several thousand kilometers. To evaluate this approach, experimental validations using one-month data of a global network with 140 IGS stations was carried out for GLONASS precise orbit determination. The results show that the GLONASS double-difference ambiguity resolution for long baselines could be achieved with an average fixing-rate of 91.4 %. Applying the fixed ambiguities as constraints, the GLONASS orbit overlapping RMS at the day boundaries could be reduced by 37.2 % in ideal cases and with an averaged reduction of about 21.4 %, which is comparable with that by the GPS ambiguity resolution. The orbit improvement is

  4. Precise determination of ferrous iron in silicate rocks

    NASA Astrophysics Data System (ADS)

    Yokoyama, Tetsuya; Nakamura, Eizo

    2002-03-01

    We have developed a highly precise method for the determination of ferrous iron (Fe 2+) in silicate rocks. Our new method is based on Wilson's procedure (1955) in which surplus V 5+ is used to oxidize Fe 2+ into Fe 3+ while equivalently reducing V 5+ into V 4+. Because V 4+ is more resistant to atmospheric oxidation than Fe 2+, Fe 2+ in the sample can be determined by measuring unreacted V 5+ by adding excess Fe 2+ after sample decomposition and then titrating the unreacted Fe 2+ with Cr 6+. With our method, which involves conditioning the sample solution with 5 M H 2SO 4 in a relatively small beaker (7 mL), the oxidation of Fe 2+ or V 4+ that leads to erroneous results can be completely avoided, even in 100-h sample decompositions at 100°C. We have measured the concentration of FeO in 15 standard silicate rock powders provided by the Geological Survey of Japan (GSJ). Analytical reproducibility was better than 0.5% (1σ) for all but those samples that had small amounts of Fe 2+ (<1.5 wt.% of FeO). Fourteen of these samples gave FeO contents significantly higher than the GSJ reference values. This likely indicates that the GSJ reference values, obtained by compiling previously published data, contain a large number of poor-quality data obtained by methods with lower recovery of Fe 2+ caused by oxidation or insufficient sample decomposition during analyses. To achieve accurate determinations of Fe 2+ in our method, several factors besides the oxidation must be considered, including: (1) long-term variations in the concentration of Fe 2+ solution must be corrected; (2) excess use of the indicator must be avoided; and (3) the formation of inert FeF + complex must be avoided during titration when using boric acid as a masking agent.

  5. Radiation force modeling for ICESat precision orbit determination

    NASA Astrophysics Data System (ADS)

    Webb, Charles Edward

    2007-12-01

    Precision orbit determination (POD) for the Ice, Cloud and land Elevation Satellite (ICESat) relies on an epoch-state batch filter, in which the dynamic models play a central role. Its implementation in the Multi-Satellite Orbit Determination Program (MSODP) originally included a box-and-wing model, representing the TOPEX/Poseidon satellite, to compute solar radiation forces. This "macro-model" has been adapted to the ICESat geometry, and additionally, extended to the calculation of forces induced by radiation reflected and emitted from the Earth. To determine the area and reflectivity parameters of the ICESat macro-model surfaces, a high-fidelity simulation of the radiation forces in low-Earth orbit was first developed, using a detailed model of the satellite, called the "micro-model". In this effort, new algorithms to compute such forces were adapted from a Monte Carlo Ray Tracing (MCRT) method originally designed to determine incident heating rates. After working with the vendor of the Thermal Synthesizer System (TSS) to implement these algorithms, a modified version of this software was employed to generate solar and Earth radiation forces for all ICESat orbit and attitude geometries. Estimates of the macro-model parameters were then obtained from a least-squares fit to these micro-model forces, applying an algorithm that also incorporated linear equality and inequality constraints to ensure feasible solutions. Three of these fitted solutions were selected for post-launch evaluation. Two represented conditions at the start and at the end of the mission, while the third comprised four separate solutions, one for each of the nominal satellite attitudes. In addition, three other sets of macro-model parameters were derived from area-weighted averaging of the micro-model reflectivities. They included solar-only and infrared-only spectral parameters, as well as a set combining these parameters. Daily POD solutions were generated with each of these macro-model sets

  6. Status of Precise Orbit Determination for Jason-2 Using GPS

    NASA Technical Reports Server (NTRS)

    Melachroinos, S.; Lemoine, F. G.; Zelensky, N. P.; Rowlands, D. D.; Pavlis, D. E.

    2011-01-01

    The JASON-2 satellite, launched in June 2008, is the latest follow-on to the successful TOPEX/Poseidon (T/P) and JASON-I altimetry missions. JASON-2 is equipped with a TRSR Blackjack GPS dual-frequency receiver, a laser retroreflector array, and a DORIS receiver for precise orbit determination (POD). The most recent time series of orbits computed at NASA GSFC, based on SLR/DORIS data have been completed using both ITRF2005 and ITRF2008. These orbits have been shown to agree radially at 1 cm RMS for dynamic vs SLRlDORIS reduced-dynamic orbits and in comparison with orbits produced by other analysis centers (Lemoine et al., 2010; Zelensky et al., 2010; Cerri et al., 2010). We have recently upgraded the GEODYN software to implement model improvements for GPS processing. We describe the implementation of IGS standards to the Jason2 GEODYN GPS processing, and other dynamical and measurement model improvements. Our GPS-only JASON-2 orbit accuracy is assessed using a number of tests including analysis of independent SLR and altimeter crossover residuals, orbit overlap differences, and direct comparison to orbits generated at GSFC using SLR and DORIS tracking, and to orbits generated externally at other centers. Tests based on SLR and the altimeter crossover residuals provide the best performance indicator for independent validation of the NASAlGSFC GPS-only reduced dynamic orbits. For the ITRF2005 and ITRF2008 implementation of our GPS-only obits we are using the IGS05 and IGS08 standards. Reduced dynamic versus dynamic orbit differences are used to characterize the remaining force model error and TRF instability. We evaluate the GPS vs SLR & DORIS orbits produced using the GEODYN software and assess in particular their consistency radially and the stability of the altimeter satellite reference frame in the Z direction for both ITRF2005 and ITRF2008 as a proxy to assess the consistency of the reference frame for altimeter satellite POD.

  7. Exoplanet mass determination using precision imaging astrometry and coronagraphy

    NASA Astrophysics Data System (ADS)

    Bendek, Eduardo; Belikov, Ruslan; Finan, Emily R.; Guyon, Olivier; Pluzhnik, Eugene; Ammons, Stephen

    2017-01-01

    Performing simultaneous high-contrast imaging and astrometry observations of a star increases the detection efficiency and characterization accuracy of single- and multiple- planetary systems around nearby stars. Combining the data generated with both techniques allows solving the Semi-Major Axis, period, and planetary mass in the system faster and more precisely than using imaging or astrometry data separately. In addition, it allows the planetary mass to be measured independently from its brightness, resolving the mass/albedo degeneracy when only direct imaging observations are available. Independent albedo determination allows calibrated planet photometry to be obtained, enabling better atmosphere characterization. To perform both direct imaging and astrometry observations, the telescope requires two instruments: a high-performance coronagraph to perform direct imaging, and a wide field camera astrometry accuracy able to deliver sub-micro arc second astrometry accuracy if earth-like planetary science is pursued. Such accuracy is only possible after calibrating relative distortions between astrometry observations, which at the sub-micro arc second regime dominates the error budget. We propose to utilize a diffractive pupil, in which an array of dots on the primary mirror generates polychromatic diffraction spikes in the focal plane, to calibrate the dynamic distortions of the optical system. In this talk, we present the results of the NASA TDEM effort to demonstrate the diffractive pupil concept on wide-field images while simultaneously performing high-contrast imaging. We also discuss the opportunity that this mission architecture could offer to future probe missions and flagships such as HabEX and LUVOIR.

  8. Precise ReOs determinations and systematics of iron meteorites

    NASA Astrophysics Data System (ADS)

    Shen, J. J.; Papanastassiou, D. A.; Wasserburg, G. J.

    1996-08-01

    The ReOs system for samples of FeNi, sulphide, and phosphide from iron meteorites was investigated. Techniques were developed which yield reproducible analyses for Re/Os at the 2%‰ level and which permit complete isotopic exchange between sample and tracer, as is necessary for concentration measurements of Re and Os by isotope dilution. High precision osmium and rhenium isotope data have been obtained using negative ion thermal ionization, with ionization efficiencies of up to 10% for Os and 20% for Re, both for normals and for Re and Os extracted from the samples. Replicate analyses of Re/Os are in good agreement, within ±2.5%o. The results show a well defined correlation line on a 187Re- 187Os evolution diagram for iron meteorites from groups IAB, IIAB, IIIAB, IVA, and IVB, all taken together. This correlation line yields a slope of 0.07863 ± 0.00031 (2σ) and initial 187Os/ 188Os = 0.09560 ± 0.00018 (2σ). If the individual groups of iron meteorites for which there is sufficient dispersion in Re/Os are considered, data on the IIAB and on the IVA irons appear to indicate a difference in age of 60 ± 45 Ma, with the IVA group being older. This age difference is qualitatively the same as obtained for PdAg data but is larger. Sulphides from two IAB iron meteorites show extremely low concentrations of Re and Os and indicate that Re and Os are not partitioned into this phase during planetary differentiation. There is evidence for recent element remobilization or contamination, corresponding to relative enrichment of Re or loss of Os in the sulphides. Schreibersites contain small but significant amounts of Re and Os, with high Re/Os relative to the metal phases and with 187Os/ 188Os much more radiogenic than in the metal. Model ages for the Schreibersites are relatively young (4.3-3.5 AE) and indicate that the Schreibersites were open-systems for ReOs at least 0.5-1 AE after the original formation of the iron meteorites. It now appears possible to use

  9. Rapid and precise determination of ATP using a modified photometer

    USGS Publications Warehouse

    Shultz, David J.; Stephens, Doyle W.

    1980-01-01

    An inexpensive delay timer was designed to modify a commercially available ATP photometer which allows a disposable tip pipette to be used for injecting either enzyme or sample into the reaction cuvette. The disposable tip pipette is as precise and accurate as a fixed-needle syringe but eliminates the problem of sample contamination and decreases analytical time. (USGS)

  10. Human milk oligosaccharides: the novel modulator of intestinal microbiota.

    PubMed

    Jeong, Kyunghun; Nguyen, Vi; Kim, Jaehan

    2012-08-01

    Human milk, which nourishes the early infants, is a source of bioactive components for the infant growth, development and commensal formulation as well. Human milk oligosaccharide is a group of complex and diverse glycans that is apparently not absorbed in human gastrointestinal tract. Although most mammalian milk contains oligosaccharides, oligosaccharides in human milk exhibit unique features in terms of their types, amounts, sizes, and functionalities. In addition to the prevention of infectious bacteria and the development of early immune system, human milk oligosaccharides are able to facilitate the healthy intestinal microbiota. Bifidobacterial intestinal microbiota appears to be established by the unilateral interaction between milk oligosaccharides, human intestinal activity and commensals. Digestibility, membrane transportation and catabolic activity by bacteria and intestinal epithelial cells, all of which are linked to the structural of human milk oligosaccharides, are crucial in determining intestinal microbiota.

  11. High precision photon flux determination for photon tagging experiments

    SciTech Connect

    Teymurazyan, A.; Ahmidouch, A.; Ambrozewicz, P.; Asratyan, A.; Baker, K.; Benton, L.; Burkert, V.; Clinton, E.; Cole, P.; Collins, P.; Dale, D.; Danagoulian, S.; Davidenko, G.; Demirchyan, R.; Deur, A.; Dolgolenko, A.; Dzyubenko, G.; Ent, R.; Evdokimov, A.; Feng, J.; Gabrielyan, M.; Gan, L.; Gasparian, A.; Glamazdin, A.; Goryachev, V.; Hardy, K.; He, J.; Ito, M.; Jiang, L.; Kashy, D.; Khandaker, M.; Kolarkar, A.; Konchatnyi, M.; Korchin, A.; Korsch, W.; Kosinov, O.; Kowalski, S.; Kubantsev, M.; Kubarovsky, V.; Larin, I.; Lawrence, D.; Li, X.; Martel, P.; Matveev, V.; McNulty, D.; Mecking, B.; Milbrath, B.; Minehart, R.; Miskimen, R.; Mochalov, V.; Nakagawa, I.; Overby, S.; Pasyuk, E.; Payen, M.; Pedroni, R.; Prok, Y.; Ritchie, B.; Salgado, C.; Shahinyan, A.; Sitnikov, A.; Sober, D.; Stepanyan, S.; Stevens, W.; Underwood, J.; Vasiliev, A.; Vishnyakov, V.; Wood, M.; Zhou, S.

    2014-12-01

    The Jefferson Laboratory PrimEx Collaboration has developed and implemented a method to control the tagged photon flux in photoproduction experiments at the 1% level over the photon energy range from 4.9 to 5.5 GeV. This method has been successfully implemented in a high precision measurement of the neutral pion lifetime. Here, we outline the experimental equipment and the analysis techniques used to accomplish this. These include the use of a total absorption counter for absolute flux calibration, a pair spectrometer for online relative flux monitoring, and a new method for post-bremsstrahlung electron counting.

  12. Oligosaccharides in feces of breast- and formula-fed babies.

    PubMed

    Albrecht, Simone; Schols, Henk A; van Zoeren, Diny; van Lingen, Richard A; Groot Jebbink, Liesbeth J M; van den Heuvel, Ellen G H M; Voragen, Alphons G J; Gruppen, Harry

    2011-10-18

    So far, little is known on the fate of oligosaccharides in the colon of breast- and formula-fed babies. Using capillary electrophoresis with laser induced fluorescence detector coupled to a mass spectrometer (CE-LIF-MS(n)), we studied the fecal oligosaccharide profiles of 27 two-month-old breast-, formula- and mixed-fed preterm babies. The interpretation of the complex oligosaccharide profiles was facilitated by beforehand clustering the CE-LIF data points by agglomerative hierarchical clustering (AHC). In the feces of breast-fed babies, characteristic human milk oligosaccharide (HMO) profiles, showing genetic fingerprints known for human milk of secretors and non-secretors, were recognized. Alternatively, advanced degradation and bioconversion of HMOs, resulting in an accumulation of acidic HMOs or HMO bioconversion products was observed. Independent of the prebiotic supplementation of the formula with galactooligosaccharides (GOS) at the level used, similar oligosaccharide profiles of low peak abundance were obtained for formula-fed babies. Feeding influences the presence of diet-related oligosaccharides in baby feces and gastrointestinal adaptation plays an important role herein. Four fecal oligosaccharides, characterized as HexNAc-Hex-Hex, Hex-[Fuc]-HexNAc-Hex, HexNAc-[Fuc]-Hex-Hex and HexNAc-[Fuc]-Hex-HexNAc-Hex-Hex, highlighted an active gastrointestinal metabolization of the feeding-related oligosaccharides. Their presence was linked to the gastrointestinal mucus layer and the blood-group determinant oligosaccharides therein, which are characteristic for the host's genotype.

  13. Precise determination of the unperturbed 8B neutrino spectrum.

    PubMed

    Roger, T; Büscher, J; Bastin, B; Kirsebom, O S; Raabe, R; Alcorta, M; Äystö, J; Borge, M J G; Carmona-Gallardo, M; Cocolios, T E; Cruz, J; Dendooven, P; Fraile, L M; Fynbo, H O U; Galaviz, D; Gasques, L R; Giri, G S; Huyse, M; Hyldegaard, S; Jungmann, K; Kruithof, W L; Lantz, M; Perea, A; Riisager, K; Saastamoinen, A; Santra, B; Shidling, P D; Sohani, M; Sørensen, A J; Tengblad, O; Traykov, E; van der Hoek, D J; Van Duppen, P; Versolato, O O; Wilschut, H W

    2012-04-20

    A measurement of the final state distribution of the (8)B β decay, obtained by implanting a (8)B beam in a double-sided silicon strip detector, is reported here. The present spectrum is consistent with a recent independent precise measurement performed by our collaboration at the IGISOL facility, Jyväskylä [O. S. Kirsebom et al., Phys. Rev. C 83, 065802 (2011)]. It shows discrepancies with previously measured spectra, leading to differences in the derived neutrino spectrum. Thanks to a low detection threshold, the neutrino spectrum is for the first time directly extracted from the measured final state distribution, thus avoiding the uncertainties related to the extrapolation of R-matrix fits. Combined with the IGISOL data, this leads to an improvement of the overall errors and the extension of the neutrino spectrum at high energy. The new unperturbed neutrino spectrum represents a benchmark for future measurements of the solar neutrino flux as a function of energy.

  14. Improvement of the precision of lattice parameter determination by nano-beam electron diffraction.

    PubMed

    Saitoh, Koh; Nakahara, Hirotaka; Tanaka, Nobuo

    2013-01-01

    A highly precise determination of lattice parameters using higher-order Laue zone (HOLZ) reflections observed in nano-beam electron diffraction is presented. The introduction of more than 40 HOLZ reflections, whose positions are corrected by considering the aberration of the electron optics and are determined with an accuracy of 0.04 nm⁻¹, allows us to achieve a remarkable high precision of a 0.02% error, which is four times higher than the precision without HOLZ reflections.

  15. Precise Determination of the Unperturbed B8 Neutrino Spectrum

    NASA Astrophysics Data System (ADS)

    Roger, T.; Büscher, J.; Bastin, B.; Kirsebom, O. S.; Raabe, R.; Alcorta, M.; Äystö, J.; Borge, M. J. G.; Carmona-Gallardo, M.; Cocolios, T. E.; Cruz, J.; Dendooven, P.; Fraile, L. M.; Fynbo, H. O. U.; Galaviz, D.; Gasques, L. R.; Giri, G. S.; Huyse, M.; Hyldegaard, S.; Jungmann, K.; Kruithof, W. L.; Lantz, M.; Perea, A.; Riisager, K.; Saastamoinen, A.; Santra, B.; Shidling, P. D.; Sohani, M.; Sørensen, A. J.; Tengblad, O.; Traykov, E.; van der Hoek, D. J.; Duppen, P. Van; Versolato, O. O.; Wilschut, H. W.

    2012-04-01

    A measurement of the final state distribution of the B8 β decay, obtained by implanting a B8 beam in a double-sided silicon strip detector, is reported here. The present spectrum is consistent with a recent independent precise measurement performed by our collaboration at the IGISOL facility, Jyväskylä [O. S. Kirsebom , Phys. Rev. C 83, 065802 (2011)PRVCAN0556-281310.1103/PhysRevC.83.065802]. It shows discrepancies with previously measured spectra, leading to differences in the derived neutrino spectrum. Thanks to a low detection threshold, the neutrino spectrum is for the first time directly extracted from the measured final state distribution, thus avoiding the uncertainties related to the extrapolation of R-matrix fits. Combined with the IGISOL data, this leads to an improvement of the overall errors and the extension of the neutrino spectrum at high energy. The new unperturbed neutrino spectrum represents a benchmark for future measurements of the solar neutrino flux as a function of energy.

  16. Precision Orbit Determination for the Lunar Reconnaissance Orbiter

    NASA Astrophysics Data System (ADS)

    Lemoine, Frank; Rowlands, David; McGarry, Jan; Neumann, Gregory; Chinn, Douglas; Mazarico, Erwan; Torrence, Mark

    The U.S. Lunar Reconnaissance Orbiter (LRO) mission will be launched in October 2008, and will carry out a detailed mapping of the Moon using a science payload of multiple instruments, including the Lunar Orbiter Laser Altimeter (LOLA), and the Lunar Reconnaissance Orbiter Camera (LROC) (Chin, 2007). One of the primary goals of the LRO mission is develop a geodetic grid for the planet. A subsidiary goal is the improvement of the lunar gravity field. The environment for POD on LRO is especially challenging. The spacecraft will orbit the Moon at a mean altitude of 50 km, and the expected error from the Lunar Prospector series of gravity models (to degree 100 or to degree 150) can be expected to be hundreds of meters. LRO will be tracked by S Band Doppler from White Sands, New Mexico, and Dongara, Australia, as well as by one-way laser ranging from Satellite Laser Ranging (SLR) tracking stations on the Earth. However, unlike the Japanese lunar mission SELENE (Kaguya), no direct tracking will be available while the spacecraft is over the lunar farside. We review the status of orbit modelling for LRO, for both the geopotential modelling and the nonconservative force models, as well as anticipated improvements. We discuss the modelling for the one-way laser ranging observable, and how the data from the one-way laser ranging (LR) system will be acquired from selected stations of the global stations of the SLR network. We discuss the orbit determination strategies which we expect to implement on this mission, including the use of altimeter crossovers from the LOLA instrument to supplement the Earth-based tracking and we review the projected orbit determination accuracies that will be attainable.

  17. [Determination of fructo-oligosaccharides in milk powder by high performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry].

    PubMed

    Liu, Yun; Ding, Tao; Xu, Suli; Wu, Bin; Shen, Chongyu; Zhang, Rui; Wang, Yan; Fei, Xiaoqing

    2015-10-01

    A method of high performance liquid chromatography-quadrupole/electrostatic field Orbitrap high resolution mass spectrometry (HPLC-Q/Orbitrap MS) was developed to determine fructo-oligosaccharides in milk powder. The milk powder samples were dissolved in deionized water. Subsequently, an aqueous solution of zinc acetate was used to precipitate protein. After centrifugation, the final aqueous solution was filtered by a polytetrafluoroethylene (PTFE) membrane with pore size of 0.22 μm. The analytes were separated on a Carbohydrate column (100 mm x 2.1 mm, 2.6 μm) through gradient elution with the combination of acetonitrile and 0.1% formic acid aqueous solution. The target-MS/MS templates were performed at isolation window of m/z 4.0 and collision energy of 30 eV in positive mode to extract the accurate product ion mass of analytes. Under the optimal condition, 1-kestose (GF2), nystose (GF3) and 1-F-β-fructofuranosyl nystose (GF4) were well separated and the accuracy of extracted mass routinely detected was below 5 x 10(-6) (5 ppm). The whole analysis time is only ten minutes. The detection limits for GF2 and GF3 were 100 μg/kg, and the detection limit for GF4 was 55 μg/kg. Good linearities were obtained in their respective linear ranges with correlation coefficients higher than 0.998. The average recoveries at three spiked levels (5, 10 and 20 mg/kg) were in the range of 75.8%-107.3% and the relative standard deviations (RSDs) were in the range of 1.6% - 8.3%. The proposed method is simple, sensitive, fast and only in need of precipitation of proteins. The interference of matrix can be eliminated through the selection of product ion. The results were convenient and reliable and thus can be used in the large batch determination of any milk powder.

  18. Precise determination of micromotion for trapped-ion optical clocks

    NASA Astrophysics Data System (ADS)

    Keller, J.; Partner, H. L.; Burgermeister, T.; Mehlstäubler, T. E.

    2015-09-01

    As relative systematic frequency uncertainties in trapped-ion spectroscopy are approaching the low 10-18 range, motional frequency shifts account for a considerable fraction of the uncertainty budget. Micromotion, a driven motion fundamentally connected to the principle of the Paul trap, is a particular concern in these systems. In this article, we experimentally investigate at this level three common methods for minimizing and determining the micromotion amplitude. We develop a generalized model for a quantitative application of the photon-correlation technique, which is applicable in the commonly encountered regime where the transition linewidth is comparable to the rf drive frequency. We show that a fractional frequency uncertainty due to the 2nd-order Doppler shift below |Δν/ν|=1 ×10-20 can be achieved. The quantitative evaluation is verified in an interleaved measurement with the conceptually simpler resolved sideband method. If not performed deep within the Lamb-Dicke regime, a temperature-dependent offset at the level of 10-19 is observed in resolved sideband measurements due to sampling of intrinsic micromotion. By direct comparison with photon-correlation measurements, we show that the simple to implement parametric heating method is sensitive to micromotion at the level of |Δν/ν|=1 ×10-20 as well.

  19. Structures of sulfated oligosaccharides in human trachea mucin glycoproteins.

    PubMed

    Sangadala, S; Bhat, U R; Mendicino, J

    1993-09-08

    The structures of high molecular weight sulfated oligosaccharide chains in mucins purified from the sputum of a patient with cystic fibrosis and blood group H determinant were established. Reduced oligosaccharides released by treatment with alkaline borohydride were separated by ion exchange chromatography on DEAE-Agarose and a fraction containing multisulfated chains was further purified by lectin affinity chromatography to completely remove small amounts of sialylated chains. A major sulfated oligosaccharide fraction containing chains with an average of 160 to 200 sugar residues was isolated by gel filtration on BioGel P-10 columns and individual subfractions were characterized by methylation analysis, periodate oxidation and sequential glycosidase digestion before and after desulfation. Carbohydrate analysis yielded Fuc, Gal and GldNAc in a ratio of 1:2:2.1 and only one galactosaminitol residue for every 160- to 200 sugar residues. The average molecular weight of oligosaccharide chains in these fractions was between 27,000 and 40,000 daltons. Structural analysis showed that these high molecular weight chains contained varying amounts of the repeating unit shown in the following oligosaccharide. Only one in about every 10 repeating units contained sulfate esters. Several shorter chains which contain 2 to 3 sulfate esters were also isolated from this multisulfated oligosaccharide fraction. The structures proposed for these oligosaccharides indicate that they are lower molecular weight chains with the same general structure as those found in the high molecular weight sulfated oligosaccharides. Taken collectively, the results of these studies show that a major sulfated oligosaccharide fraction in respiratory mucin purified from the mucus of patients with cystic fibrosis contains high molecular weight branched chains that consist of a repeating oligosaccharide sequence with sulfate linked to the 6 positions of galactose and possibly GlcNAc residues in the side chains.

  20. Oligosaccharides in Food and Agriculture

    NASA Astrophysics Data System (ADS)

    Collins, Michelle E.; Rastall, Robert A.

    Oligosaccharides are an integral part of the daily diet for humans and animals. They are primarily used for their nutritional properties, however they are currently receiving much attention due to their physiological effect on the microflora of the gastrointestinal tract. Galacto-oligosaccharides and the fructan-type oligosaccharides, namely FOS and inulin are well established as beneficial to the host and are classified as prebiotic based on data from clinical studies. These compounds dominate this sector of the market, although there are oligosaccharides emerging which have produced very interesting in vitro results in terms of prebiotic status and human trials are required to strengthen the claim. Such compounds include pectic oligosaccharides, gluco-oligosaccharides, gentio-oligosaccharides, kojio-oligosaccharides, and alternan oligosaccharides. The raw materials for production of these prebiotic compounds are derived from natural sources such as plants but also from by products of the food processing industry. In addition to being prebiotic these compounds can be incorporated into foodstuffs due to the physiochemical properties they possess.

  1. Profiles of human milk oligosaccharides and production of some human milk oligosaccharides in transgenic animals.

    PubMed

    Prieto, Pedro Antonio

    2012-05-01

    During the decade of the 1990s and the first years of the current century, our group embarked on a project to study and synthesize human milk oligosaccharides. This report describes 2 unexpected collateral observations from that endeavor. The first observation was the detection and confirmation of 2 rare neutral human milk oligosaccharides profiles that were uncovered while assessing oligosaccharide content in hundreds of samples of human milk. One of these lacked fucosylated structures altogether, and the other lacked the oligosaccharide 3-fucosyllactose [Galβ1-4(Fucα1-3)Glc]. We used glycoconjugate probes to determine whether the unusual profiles were mirrored by fucosylation of milk glycoproteins. The results show that the lack of fucosylated oligosaccharides in these samples corresponds to the absence of equivalent fucosylated motifs in milk glycoproteins. The second finding was a shortened and distinct lactation process in transgenic rabbits expressing the human fucosyltransferase 1. During the first day of lactation, these animals expressed milk that contained both lactose and 2'-fucosylactose, but on the second day, the production of milk was severely diminished, and by the fourth day, no lactose was detected in their milk. Meanwhile, the concentration of fucosylated glycoproteins increased from the onset of lactation through its premature termination. These 2 findings may shed light on the glycobiology of milk and perhaps on mammary gland differentiation.

  2. Profiles of Human Milk Oligosaccharides and Production of Some Human Milk Oligosaccharides in Transgenic Animals12

    PubMed Central

    Prieto, Pedro Antonio

    2012-01-01

    During the decade of the 1990s and the first years of the current century, our group embarked on a project to study and synthesize human milk oligosaccharides. This report describes 2 unexpected collateral observations from that endeavor. The first observation was the detection and confirmation of 2 rare neutral human milk oligosaccharides profiles that were uncovered while assessing oligosaccharide content in hundreds of samples of human milk. One of these lacked fucosylated structures altogether, and the other lacked the oligosaccharide 3-fucosyllactose [Galβ1–4(Fucα1–3)Glc]. We used glycoconjugate probes to determine whether the unusual profiles were mirrored by fucosylation of milk glycoproteins. The results show that the lack of fucosylated oligosaccharides in these samples corresponds to the absence of equivalent fucosylated motifs in milk glycoproteins. The second finding was a shortened and distinct lactation process in transgenic rabbits expressing the human fucosyltransferase 1. During the first day of lactation, these animals expressed milk that contained both lactose and 2′-fucosylactose, but on the second day, the production of milk was severely diminished, and by the fourth day, no lactose was detected in their milk. Meanwhile, the concentration of fucosylated glycoproteins increased from the onset of lactation through its premature termination. These 2 findings may shed light on the glycobiology of milk and perhaps on mammary gland differentiation. PMID:22585925

  3. DORIS precise orbit determination and location system performances of ultra stable oscillators

    NASA Astrophysics Data System (ADS)

    Brunet, M.

    1992-06-01

    Elements of the DORIS (Doppler precise positioning System) performances and performances of the DORIS USO (Ultra Stable Oscillators) are described. The DORIS system was designed and developed to meet new needs in precision orbit determination and high accuracy beacon location. DORIS payload was integrated on three French SPOT satellites and on the Topex-Poseidon NASA satellite. The first model DORIS SPOT 2 began operating on 22 Jan. 1990. The fundamental measurement precision depends strongly on the stability of USO, which are used in the onboard receiver, and in ground location beacons.

  4. High precision determination of bromine isotope ratio by GC-MC-ICPMS

    NASA Astrophysics Data System (ADS)

    Gelman, Faina; Halicz, Ludwik

    2010-01-01

    This work presents a new methodology for the precise determination of bromine isotope ratio in individual organic compounds based on the simultaneous introduction of brominated organic compounds and strontium as an external spike into MC-ICPMS. Using the proposed methodology, an external precision (2[sigma]) up to 0.1[per mille sign] has been attained. The new approach for the bromine isotope ratio analysis could be applied for the investigating the fate of the organobromine compounds in the environment.

  5. Centroiding Experiment for Determining the Positions of Stars with High Precision

    NASA Astrophysics Data System (ADS)

    Yano, T.; Araki, H.; Hanada, H.; Tazawa, S.; Gouda, N.; Kobayashi, Y.; Yamada, Y.; Niwa, Y.

    2010-12-01

    We have experimented with the determination of the positions of star images on a detector with high precision such as 10 microarcseconds, required by a space astrometry satellite, JASMINE. In order to accomplish such a precision, we take the following two procedures. (1) We determine the positions of star images on the detector with the precision of about 0.01 pixel for one measurement, using an algorithm for estimating them from photon weighted means of the star images. (2) We determine the positions of star images with the precision of about 0.0001-0.00001 pixel, which corresponds to that of 10 microarcseconds, using a large amount of data over 10000 measurements, that is, the error of the positions decreases according to the amount of data. Here, we note that the procedure 2 is not accomplished when the systematic error in our data is not excluded adequately even if we use a large amount of data. We first show the method to determine the positions of star images on the detector using photon weighted means of star images. This algorithm, used in this experiment, is very useful because it is easy to calculate the photon weighted mean from the data. This is very important in treating a large amount of data. Furthermore, we need not assume the shape of the point spread function in deriving the centroid of star images. Second, we show the results in the laboratory experiment for precision of determining the positions of star images. We obtain that the precision of estimation of positions of star images on the detector is under a variance of 0.01 pixel for one measurement (procedure 1). We also obtain that the precision of the positions of star images becomes a variance of about 0.0001 pixel using about 10000 measurements (procedure 2).

  6. Complex carbohydrates of red wine: characterization of the extreme diversity of neutral oligosaccharides by ESI-MS.

    PubMed

    Doco, Thierry; Williams, Pascale; Meudec, Emmanuelle; Cheynier, Véronique; Sommerer, Nicolas

    2015-01-21

    The major neutral oligosaccharides of a Carignan red wine have been characterized for the first time. The oligosaccharides were prepared after removal of phenolic compounds by polyamide chromatography and of polysaccharides by alcohol precipitation and then were fractionated by anion exchange and size-exclusion chromatography. In a second step, the glycosyl composition and linkages of wine oligosaccharides were determined. Oligosaccharide fractions were analyzed by mass spectrometry (MS) with an electrospray ionization (ESI) source and an ion trap mass analyzer after separation by hydrophilic interaction liquid chromatography on a Nucleodur HILIC column (zwitterionic sulfoalkyl betaine stationary phase). Glycosyl residue composition analysis showed the predominant presence of arabinose, with galactose, rhamnose, and mannose in lower proportion. Neutral oligosaccharides were present at a concentration of 185 mg/L in this wine. The MS spectra in the negative ion mode of the oligosaccharide fractions showed a series of oligosaccharidic structures corresponding to oligo-arabinans often linked to the basic unit α-l-Rhap-(1 → 4)-α-d-GalpA. The wine oligosaccharides identified correspond to arabino-oligosaccharides, rhamno-arabino-oligosaccharides, and different rhamnogalacturonan-arabino-oligosaccharides with DP ranging from 5 to 49, resulting from the degradation of grape cell wall pectins. Oligosaccharides have an extreme diversity, with more than 100 peaks detected in HPLC-ESI-MS spectra corresponding each to at least one oligosaccharidic structure.

  7. Accurate and precise determination of isotopic ratios by MC-ICP-MS: a review.

    PubMed

    Yang, Lu

    2009-01-01

    For many decades the accurate and precise determination of isotope ratios has remained a very strong interest to many researchers due to its important applications in earth, environmental, biological, archeological, and medical sciences. Traditionally, thermal ionization mass spectrometry (TIMS) has been the technique of choice for achieving the highest accuracy and precision. However, recent developments in multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) have brought a new dimension to this field. In addition to its simple and robust sample introduction, high sample throughput, and high mass resolution, the flat-topped peaks generated by this technique provide for accurate and precise determination of isotope ratios with precision reaching 0.001%, comparable to that achieved with TIMS. These features, in combination with the ability of the ICP source to ionize nearly all elements in the periodic table, have resulted in an increased use of MC-ICP-MS for such measurements in various sample matrices. To determine accurate and precise isotope ratios with MC-ICP-MS, utmost care must be exercised during sample preparation, optimization of the instrument, and mass bias corrections. Unfortunately, there are inconsistencies and errors evident in many MC-ICP-MS publications, including errors in mass bias correction models. This review examines "state-of-the-art" methodologies presented in the literature for achievement of precise and accurate determinations of isotope ratios by MC-ICP-MS. Some general rules for such accurate and precise measurements are suggested, and calculations of combined uncertainty of the data using a few common mass bias correction models are outlined.

  8. Comparison and Analysis of BeiDou Satellite Single-system Precise Orbit Determination

    NASA Astrophysics Data System (ADS)

    Liu, W. P.; Hao, J. M.; Deng, K.; Chen, Y. L.

    2016-09-01

    The method of double-difference dynamic precise orbit determination for BeiDou satellites by using both carrier phase and smoothed pseudo-range is presented. The data processing flows of zero-difference and double-difference dynamic precise orbit determination for BeiDou satellites are presented. And the two methods are analyzed. The precision of two methods is compared based on the real data. The results show that in the condition of stations layout and by using the two methods, the three-dimension precision of GEO (Geostationary Earth Orbit Satellite) can reach about 1 m, and those of IGSO (Inclined Geosynchronous Earth Orbit Satellite) and MEO (Medium Earth Orbit Satellite) can be better than 0.5 m. And the radial precision of the three kinds of orbit satellites can be all better than 10 cm. Compared with the zero-difference dynamic method, the orbit precision of GEO is better with the double-difference dynamic method, and that of IGSO is comparable, but that of MEO is worse.

  9. Functional oligosaccharides: application and manufacture.

    PubMed

    Rastall, R A

    2010-01-01

    Oligosaccharides are attracting increasing interest as prebiotic functional food ingredients. They can be extracted or obtained by enzymatic hydrolysis from a variety of biomass sources or synthesized from simple oligosaccharides by enzymatic transfer reactions. The major prebiotic oligosaccharides on the market are inulin, fructo-oligosaccharides, and galacto-oligosaccharides. They have been evaluated using a range of in vitro and in vivo methods, although there is a need for more large-scale human trials using modern microbiological methods. Prebiotics are being studied for their effects on gut health and well being and specific clinical conditions, including colon cancer, inflammatory bowel disease (IBD), acute infections, and mineral absorption. Developing understanding of the functional ecology of the human gut is influencing current thinking on what a prebiotic might achieve and is providing new targets for prebiotic intervention.

  10. Highly sensitive derivatization reagents possessing positively charged structures for the determination of oligosaccharides in glycoproteins by high-performance liquid chromatography electrospray ionization tandem mass spectrometry.

    PubMed

    Min, Jun Zhe; Nagai, Keisuke; Shi, Qing; Zhou, Wenjun; Todoroki, Kenichiro; Inoue, Koichi; Lee, Yong-Ill; Toyo'oka, Toshimasa

    2016-09-23

    We have developed three kinds of novel derivatization reagents (4-CEBTPP, 4-CBBTPP, 5-COTPP) with triphenylphosphine (TPP) as a basic structure carrying a permanent positive charge for resolution of the oligosaccharides in glycoprotein using high-performance liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). The synthesized reagents reacted with the sialylglycosylamine of the sialylglycopeptide after treatment by PNGase F. The final derivatives were analyzed by ESI-MS and sensitively detected in the selected reaction monitoring (SRM) mode. Furthermore, the limits of detection (S/N=3) on the SRM chromatograms were at the fmol level (30fmol). Therefore, we used the limit of detection of the reagent products detected by the SRM and evaluated the utility of each reagent. Among the reagents, the positively charged 4-CEBTPP derivative's peak area was the highest; 4-CEBTPP with a positively charged structure showed about a 20 times greater sensitivity for the glycosylamine of the SGP product compared to the conventional fluorescence reagent, Fmoc-Cl. In addition, various fragment ions based on the carbohydrate units also appeared in the MS/MS spectra. Among the fragment ions, m/z 627.37 (CE=40eV) corresponding to 4-CEBTPP-GlcNAc and m/z 120.09 (CE=100eV) corresponding to 4-CEBTPP are the most important ones for identifying the oligosaccharide. 4-CEBTPP-SGA was easily identified by the selected-ion chromatogram in the product ion scan (m/z 120.09) and in the precursor ion scan (m/z 627.37) by MS/MS detection. The derivatized analytes have a high ionization efficiency and they are detected with a high sensitivity in the electrospray ionization. The novel derivatization reagent with a multi-function provided a higher sensitivity for the oligosaccharide analysis, as well as a better specificity and feasibility. Furthermore, several oligosaccharides in fetuin and ribonuclease B were successfully identified by the proposed procedure.

  11. Stable isotope labeling of oligosaccharide cell surface antigens

    SciTech Connect

    Unkefer, C.J.; Silks, L.A. III; Martinez, R.A.

    1998-12-31

    The overall goal of this Laboratory Directed Research and Development (LDRD) project was to develop new methods for synthesis of {sup 13}C-labeled oligosaccharides that are required for nuclear magnetic resonance (NMR) studies of their solution conformation. Oligosaccharides are components of the cell`s outer surface and are involved in important processes such as cell-cell recognition and adhesion. Recently, Danishefsky and coworkers at Slone-Kettering Cancer Center developed a method for the solid-phase chemical synthesis of oligosaccharides. The specific goal of this LDRD project was to prepare uniform {sup 13}C-labeled aldohexose precursors required for the solid-phase synthesis of the Lewis blood-group antigenic determinants. We report the synthesis of {sup 13}C-labeled D-glucal, D-galactal and Fucosyl precursors. We have been collaborating with the Danishefsky group on the synthesis of the Lewis oligosaccharides and the NMR analysis of their solution conformation.

  12. Sucrose and Related Oligosaccharides

    NASA Astrophysics Data System (ADS)

    Eggleston, Gillian

    Sucrose (α-D-glucopyranosyl-(1↔2)-β-D-fructofuranoside) is the most common low-molecular-weight sugar found in the plant kingdom. It is ubiquitously known as common table sugar and primarily produced industrially from sugarcane (Saccharum officinarum) and sugar beet (Beta vulgaris); the basics of the industrial manufacture of sucrose are outlined in this chapter. Commercial sucrose has a very high purity (> 99.9%) making it one of the purest organic substances produced on an industrial scale. Value-addition to sucrose via chemical and biotechnological reactions is becoming more important for the diversification of the sugar industry to maintain the industries' competitiveness in a world increasingly turning to a bio-based economy. The basis for the chemical reactivity of sucrose is the eight hydroxyl groups present on the molecule, although, sucrose chemical reactivity is regarded as difficult. Increasing use of enzymatic biotechnological techniques to derivatize sucrose is expected, to add special functionalities to sucrose products like biodegradability, biocompatibility, and non-toxicity. Analysis of sucrose by colorimetric, enzymatic, oxidation-reduction and chromatography methods are discussed. Oligosaccharides related to sucrose are outlined in detail and include sucrose-based plant, honey and in vitro oligosaccharides.

  13. Precise characterization of Guatemalan obsidian sources, and source determination of artifacts from Quirigua

    SciTech Connect

    Stross, F.H.; Sheets, P.; Asaro, F.; Michel, H.V.

    1983-01-01

    For the determination of provenience of obsidian artifacts, precise and accurate measurements of composition patterns of the geologic sources are necessary for definitive and cost-effective assignments. Inter-comparison of data from different laboratories is often difficult. Suggestions for maximizing the usefulness of data already in the literature are made, contributions to a useful data bank of source composition patterns are recorded, and provenience determinations of 30 artifacts excavated in Quirigua, Guatemala are presented to exemplify the technique.

  14. A high precision attitude determination and control system for the UYS-1 nanosatellite

    NASA Astrophysics Data System (ADS)

    Chaurais, J. R.; Ferreira, H. C.; Ishihara, J. Y.; Borges, R. A.; Kulabukhov, A. M.; Larin, V. A.; Belikov, V. V.

    This paper presents the design of a high precision attitude determination and control system for the UYS-1 Ukrainian nanosatellite. Its main task is the 3-axis stabilization with less than 0.5° angle errors, so the satellite may take high precision photos of Earth's surface. To accomplish this task, this system comprises a star tracker and three reaction wheels. To avoid external disturbances and actuators faults, a PD-type and a PID-type robust controllers are simulated and the results are compared to an empirically adjusted PD controller.

  15. The GLAS Algorithm Theoretical Basis Document for Precision Orbit Determination (POD)

    NASA Technical Reports Server (NTRS)

    Rim, Hyung Jin; Yoon, S. P.; Schultz, Bob E.

    2013-01-01

    The Geoscience Laser Altimeter System (GLAS) was the sole instrument for NASA's Ice, Cloud and land Elevation Satellite (ICESat) laser altimetry mission. The primary purpose of the ICESat mission was to make ice sheet elevation measurements of the polar regions. Additional goals were to measure the global distribution of clouds and aerosols and to map sea ice, land topography and vegetation. ICESat was the benchmark Earth Observing System (EOS) mission to be used to determine the mass balance of the ice sheets, as well as for providing cloud property information, especially for stratospheric clouds common over polar areas. The GLAS instrument operated from 2003 to 2009 and provided multi-year elevation data needed to determine changes in sea ice freeboard, land topography and vegetation around the globe, in addition to elevation changes of the Greenland and Antarctic ice sheets. This document describes the Precision Orbit Determination (POD) algorithm for the ICESat mission. The problem of determining an accurate ephemeris for an orbiting satellite involves estimating the position and velocity of the satellite from a sequence of observations. The ICESatGLAS elevation measurements must be very accurately geolocated, combining precise orbit information with precision pointing information. The ICESat mission POD requirement states that the position of the instrument should be determined with an accuracy of 5 and 20 cm (1-s) in radial and horizontal components, respectively, to meet the science requirements for determining elevation change.

  16. Oligosaccharides: state of the art.

    PubMed

    Delzenne, N M

    2003-02-01

    Oligosaccharides, consisting of a mixture of hexose oligomers with a variable extent of polymerisation, are food products with interesting nutritional properties. They may be naturally present in food, mostly in fruits, vegetables or grains, or produced by biosynthesis from natural sugars or polysaccharides and added to food products because of their nutritional properties or organoleptic characteristics. The dietary intake of oligosaccharides is difficult to estimate, but it may reach 3-13 g/d per person (for fructo-oligosaccharides), depending on the population. The extent of resistance to enzymic reactions occurring in the upper part of the gastrointestinal tract allows oligosaccharides to become 'colonic nutrients', as some intestinal bacterial species express specific hydrolases and are able to convert oligosaccharides into short-chain fatty acids (acetate, lactate, propionate, butyrate) and/or gases by fermentation. Oligosaccharides that selectively promote some interesting bacterial species (e.g. lactobacilli, bifidobacteria), and thus equilibrate intestinal microflora, are now termed prebiotics. The pattern of short-chain fatty acid production in the caeco-colon, as well as the prebiotic effect, if demonstrated, are dynamic processes that vary with the type of oligosaccharide (e.g. extent of polymerisation, nature of hexose moieties), the duration of the treatment, the initial composition of flora or the diet in which they are incorporated. Experimental data obtained in vitro and in vivo in animals, and also recent data obtained in human subjects, support the involvement of dietary oligosaccharides in physiological processes in the different intestinal cell types (e.g. mucins production, cell division, immune cells function, ionic transport) and also outside the gastrointestinal tract (e.g. hormone production, lipid and carbohydrates metabolism). The present paper gives an overview of the future development of oligosaccharides, newly recognised as dietary

  17. Precise determination of magnetic moment of a fluxoid quantum in a superconducting microring

    NASA Astrophysics Data System (ADS)

    Choi, Heonhwa; Kim, Yun Won; Lee, Soon-Gul; Choi, Mahn-Soo; Kim, Min-Seok; Choi, Jae-Hyuk

    2017-02-01

    Using dynamic cantilever magnetometry and experimentally determining the cantilever's vibrational mode shape, we precisely measured the magnetic moment of a lithographically defined micron-sized superconducting Nb ring, a key element for the previously proposed subpiconewton force standard. The magnetic moments due to individual magnetic fluxoids and a diamagnetic response were independently determined at T =4.3 K, with a subfemtoampere-square-meter resolution. The results show good agreement with the theoretical estimation yielded by the Brandt and Clem model within the spring constant determination accuracy.

  18. 40 CFR 80.584 - What are the precision and accuracy criteria for approval of test methods for determining the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false What are the precision and accuracy....584 What are the precision and accuracy criteria for approval of test methods for determining the sulfur content of motor vehicle diesel fuel, NRLM diesel fuel, and ECA marine fuel? (a) Precision....

  19. 40 CFR 80.584 - What are the precision and accuracy criteria for approval of test methods for determining the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false What are the precision and accuracy....584 What are the precision and accuracy criteria for approval of test methods for determining the sulfur content of motor vehicle diesel fuel, NRLM diesel fuel, and ECA marine fuel? (a) Precision....

  20. A randomised, double-blind, placebo controlled cross-over study to determine the gastrointestinal effects of consumption of arabinoxylan-oligosaccharides enriched bread in healthy volunteers

    PubMed Central

    2012-01-01

    Background Prebiotics are food ingredients, usually non-digestible oligosaccharides, that are selectively fermented by populations of beneficial gut bacteria. Endoxylanases, altering the naturally present cereal arabinoxylans, are commonly used in the bread industry to improve dough and bread characteristics. Recently, an in situ method has been developed to produce arabinoxylan-oligosaccharides (AXOS) at high levels in breads through the use of a thermophilic endoxylanase. AXOS have demonstrated potentially prebiotic properties in that they have been observed to lead to beneficial shifts in the microbiota in vitro and in murine, poultry and human studies. Methods A double-blind, placebo controlled human intervention study was undertaken with 40 healthy adult volunteers to assess the impact of consumption of breads with in situ produced AXOS (containing 2.2 g AXOS) compared to non-endoxylanase treated breads. Volatile fatty acid concentrations in faeces were assessed and fluorescence in situ hybridisation was used to assess changes in gut microbial groups. Secretory immunoglobulin A (sIgA) levels in saliva were also measured. Results Consumption of AXOS-enriched breads led to increased faecal butyrate and a trend for reduced iso-valerate and fatty acids associated with protein fermentation. Faecal levels of bifidobacteria increased following initial control breads and remained elevated throughout the study. Lactobacilli levels were elevated following both placebo and AXOS-breads. No changes in salivary secretory IgA levels were observed during the study. Furthermore, no adverse effects on gastrointestinal symptoms were reported during AXOS-bread intake. Conclusions AXOS-breads led to a potentially beneficial shift in fermentation end products and are well tolerated. PMID:22657950

  1. High-Precision Microwave Spectroscopy of Muonium for Determination of Muonic Magnetic Moment

    NASA Astrophysics Data System (ADS)

    Torii, H. A.; Higashi, Y.; Higuchi, T.; Matsuda, Y.; Mizutani, T.; Tajima, M.; Tanaka, K. S.; Ueno, Y.; Fukao, Y.; Iinuma, H.; Ikedo, Y.; Kadono, R.; Kawamura, N.; Koda, A.; Kojima, K. M.; Mibe, T.; Miyake, Y.; Nagamine, K.; Nishiyama, K.; Ogitsu, T.; Okubo, R.; Saito, N.; Sasaki, K.; Shimomura, K.; Strasser, P.; Sugano, M.; Toyoda, A.; Ueno, K.; Yamamoto, A.; Yoshida, M.; Ishida, K.; Iwasaki, M.; Kamigaito, O.; Tomono, D.; Kanda, S.; Kubo, K.; Aoki, M.; Torikai, E.; Kawall, D.

    2016-02-01

    The muonium atom is a system suitable for precision measurements for determination of muon’s fundamental properties as well as for the test of quantum electrodynamics (QED). A microwave spectroscopy experiment of this exotic atom is being prepared at J-PARC, jointly operated by KEK and JAEA in Japan, aiming at an improved relative precision at a level of 10-8 in determination of the muonic magnetic moment. A major improvement of statistical uncertainty is expected with the higher muon intensity of the pulsed beam at J-PARC, while reduction of various sources of systematic uncertainties are being studied: those arising from microwave power fluctuations, magnetic field inhomogeneity, muon stopping distribution and atomic collisional shift of resonance frequencies. Experimental strategy and methods are presented in this paper, with an emphasis on our recent development of apparatuses and evaluation of systematic uncertainties.

  2. Precise momentum determination of the external COSY proton beam near 1930 MeV//c

    NASA Astrophysics Data System (ADS)

    Betigeri, M. G.; Bojowald, J.; Budzanowski, A.; Chatterjee, A.; Drochner, M.; Ernst, J.; Förtsch, S.; Freindl, L.; Frekers, D.; Garske, W.; Grewer, K.; Hamacher, A.; Hawash, M.; Igel, S.; Ilieva, I.; Jahn, R.; Jarczyk, L.; Kemmerling, G.; Kilian, K.; Kliczewski, S.; Klimala, W.; Kolev, D.; Kutsarova, T.; Lieb, B. J.; Lippert, G.; Machner, H.; Magiera, A.; Maier, R.; Nann, H.; Plendl, H. S.; Protic, D.; Razen, B.; von Rossen, P.; Roy, B.; Siudak, R.; Smyrski, J.; Strzałkowski, A.; Tsenov, R.; Zolnierczuk, P. A.; Zwoll, K.; GEM Collaboration

    1999-05-01

    We present a method to determine precisely the absolute momentum of the external proton beam from the Jülich Cooler Synchrotron COSY near 1930 MeV /c. In the pp → d π+ reaction at 1930.477 MeV /c incident beam momentum, the forward going pions ( θ c.m.=0° ) and the backward going deuterons ( θ c.m.=180° ) have the same laboratory momentum. Such coincident pion-deuteron events are detected in the focal plane of the magnetic spectrometer BIG KARL located at θ lab=0° . Using the nearly linear dependence of the difference between the measured pion and deuteron momenta as a function of the proton beam momentum, the absolute momentum of the external proton beam from COSY near 1930 MeV /c was determined with a precision of 5.2×10 -5.

  3. Precision Attitude Determination System (PADS) design and analysis. Two-axis gimbal star tracker

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Development of the Precision Attitude Determination System (PADS) focused chiefly on the two-axis gimballed star tracker and electronics design improved from that of Precision Pointing Control System (PPCS), and application of the improved tracker for PADS at geosynchronous altitude. System design, system analysis, software design, and hardware design activities are reported. The system design encompasses the PADS configuration, system performance characteristics, component design summaries, and interface considerations. The PADS design and performance analysis includes error analysis, performance analysis via attitude determination simulation, and star tracker servo design analysis. The design of the star tracker and electronics are discussed. Sensor electronics schematics are included. A detailed characterization of the application software algorithms and computer requirements is provided.

  4. Precise orbit determination for NASA's earth observing system using GPS (Global Positioning System)

    NASA Technical Reports Server (NTRS)

    Williams, B. G.

    1988-01-01

    An application of a precision orbit determination technique for NASA's Earth Observing System (EOS) using the Global Positioning System (GPS) is described. This technique allows the geometric information from measurements of GPS carrier phase and P-code pseudo-range to be exploited while minimizing requirements for precision dynamical modeling. The method combines geometric and dynamic information to determine the spacecraft trajectory; the weight on the dynamic information is controlled by adjusting fictitious spacecraft accelerations in three dimensions which are treated as first order exponentially time correlated stochastic processes. By varying the time correlation and uncertainty of the stochastic accelerations, the technique can range from purely geometric to purely dynamic. Performance estimates for this technique as applied to the orbit geometry planned for the EOS platforms indicate that decimeter accuracies for EOS orbit position may be obtainable. The sensitivity of the predicted orbit uncertainties to model errors for station locations, nongravitational platform accelerations, and Earth gravity is also presented.

  5. On the Mitigation of Solar Index Variability for High Precision Orbit Determination in Low Earth Orbit

    DTIC Science & Technology

    2016-09-16

    measurements of solar Lyman-α emissions and X-ray emissions. This index was newly incorporated in the JB08 model, and is used to model energy transfer to the...On the Mitigation of Solar Index Variability for High Precision Orbit Determination in Low Earth Orbit John G. Warner ∗ and Annie Lum ∗ US Naval...atmosphere models used to predict the drag force experienced by a satellite may rely on input parameters such as solar flux and geomagnetic indices

  6. Precise orbit determination of Compass-M1: a primary result

    NASA Astrophysics Data System (ADS)

    Sun, Baoqi

    On April 13, 2007, the first experiment satellite, Compass-M1, of China's the second generation Compass Navigation system was successfully launched. Unlike previous Compass satellites, Compass-M1 is the first satellite in medium earth orbit (MEO), and broadcast navigation signals in multi-frequencies in L-band. If signals were received from more than four satellites, users can determine their locations in a passive manner like using GPS. A primary result of precise orbit determination of Compass-M1 is presented in this paper. Five tracking stations, all located in China, are used. Double-frequency code and carrier phase observations are processed in zero-difference mode. Receiver and satellite clocks are modeled by linear or quadratic polynomial. The radiation pressure model is the so-called extended CODE orbit model, and an a priori model is introduced according to the size and physical attribute of Compass-M1. The solution is based on 3-day arc dynamical precise orbit determination. Estimated parameters include six keplerian orbit elements, two radiation pressure model parameters and clock polynomial coefficients. Orbit overlap difference and validating with SLR indicate that the accuracy of the precise orbit is quite exciting and exceeds our expectation.

  7. Blackbody Infrared Radiative Dissociation of Protonated Oligosaccharides

    NASA Astrophysics Data System (ADS)

    Fentabil, Messele A.; Daneshfar, Rambod; Kitova, Elena N.; Klassen, John S.

    2011-12-01

    The dissociation pathways, kinetics, and energetics of protonated oligosaccharides in the gas phase were investigated using blackbody infrared radiative dissociation (BIRD). Time-resolved BIRD measurements were performed on singly protonated ions of cellohexaose (Cel6), which is composed of β-(1 → 4)-linked glucopyranose rings, and five malto-oligosaccharides (Malx, where x = 4-8), which are composed of α-(1 → 4)-linked glucopyranose units. At the temperatures investigated (85-160 °C), the oligosaccharides dissociate at the glycosidic linkages or by the loss of a water molecule to produce B- or Y-type ions. The Y ions dissociate to smaller Y or B ions, while the B ions yield exclusively smaller B ions. The sequential loss of water molecules from the smallest B ions (B1 and B2) also occurs. Rate constants for dissociation of the protonated oligosaccharides and the corresponding Arrhenius activation parameters (Ea and A) were determined. The Ea and A-factors measured for protonated Malx (x > 4) are indistinguishable within error (~19 kcal mol-1, 1010 s-1), which is consistent with the ions being in the rapid energy exchange limit. In contrast, the Arrhenius parameters for protonated Cel6 (24 kcal mol-1, 1012 s-1) are significantly larger. These results indicate that both the energy and entropy changes associated with the glycosidic bond cleavage are sensitive to the anomeric configuration. Based on the results of this study, it is proposed that formation of B and Y ions occurs through a common dissociation mechanism, with the position of the proton establishing whether a B or Y ion is formed upon glycosidic bond cleavage.

  8. Experimental study on the precise orbit determination of the BeiDou navigation satellite system.

    PubMed

    He, Lina; Ge, Maorong; Wang, Jiexian; Wickert, Jens; Schuh, Harald

    2013-03-01

    The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS) network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better.

  9. Experimental Study on the Precise Orbit Determination of the BeiDou Navigation Satellite System

    PubMed Central

    He, Lina; Ge, Maorong; Wang, Jiexian; Wickert, Jens; Schuh, Harald

    2013-01-01

    The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS) network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better. PMID:23529116

  10. Precision orbit determination for TOPEX/Poseidon using TDRSS Doppler tracking data

    NASA Astrophysics Data System (ADS)

    Lerch, F. J.; Doll, C. E.; Marshall, J. A.; Luthcke, S. B.; Williamson, R. G.; Klosko, S. M.; McCarthy, J. J.; Eddy, W. F.

    1995-08-01

    Precision orbit determination on the TOPEX/Poseidon (T/P) altimeter satellite is now being routinely achieved with sub-5cm radial and sub-15 cm total positioning accuracy using state-of-the-art modeling with precision tracking provided by a combination of: (a) global Satellite Laser Ranging (SLR) and Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS), or (b) the Global Positioning System (GPS) Constellation which provides pseudo-range and carrier phase observations. The geostationary Tracking and Data Relay Satellite System (TDRSS) satellites are providing the operational tracking and communication support for this mission. The TDRSS Doppler data are of high precision (0.3 mm/s nominal noise levels). Unlike other satellite missions supported operationally by TDRSS, T/P has high quality independent tracking which enables absolute orbit accuracy assessments. In addition, the T/P satellite provides extensive geometry for positioning a satellite at geostationary altitude, and thus the TDRSS-T/P data provides an excellent means for determining the TDRS orbits. Arc lengths of 7 and 10 days with varying degrees of T/P spacecraft attitude complexity are studied. Sub-meter T/P total positioning error is achieved when using the TDRSS range-rate data, with radial orbit errors of 10.6 cm and 15.5 cm RMS for the two arcs studied. Current limitations in the TDRSS precision orbit determination capability include mismodeling of numerous TDRSS satellite-specific dynamic and electronic effects, and in the inadequate treatment of the propagation delay and bending arising from the wet troposphere and ionosphere.

  11. A Task-Analytic Approach to the Determination of Training Requirements for the Precision Descent

    NASA Technical Reports Server (NTRS)

    Smith, Nancy; Rosekind, Mark (Technical Monitor)

    1996-01-01

    A task-analytic approach was used to evaluate the results from an experiment comparing two training methods for the "Precision Descent," a cockpit procedure designed to complement a new, computer-based air traffic control advisory system by allowing air traffic controllers to assign precise descent trajectories to aircraft. A task model was developed for the procedure using a methodology that represents four different categories of task-related knowledge: (1) ability to determine current flight goals; (2) ability to assess the current flight situation relative to those goals; (3) operational knowledge about flight-related tasks; and (4) knowledge about task selection. This model showed what knowledge experienced pilots already possessed, and how that knowledge was supplemented by training material provided in the two training conditions. All flight crews were given a "Precision Descent Chart" that explained the procedure's clearances and compliance requirements. This information enabled pilots to establish appropriate flight goals for the descent, and to monitor their compliance with those goals. In addition to this chart, half of the crews received a "Precision Descent Bulletin" containing technique recommendations for performing procedure-related tasks. The Bulletin's recommendations supported pilots in task selection and helped clarify the procedure's compliance requirements. Eight type-rated flight crews flew eight Precision Descents in a Boeing 747-400 simulator, with four crews in each of the two training conditions. Both conditions (Chart and Chart-with-Bulletin) relied exclusively on the use of those documents to introduce the procedure. No performance feedback was provided during the experiment. Preliminary result show better procedure compliance and higher acceptability ratings from flight crews in the Chart-with-Bulletin condition. These crews performed flight-related tasks less efficiently, however, using the simpler but less efficient methods suggested

  12. GNSS orbit determination by precise modeling of non-gravitational forces acting on satellite's body

    NASA Astrophysics Data System (ADS)

    Wielgosz, Agata; Kalarus, Maciej; Liwosz, Tomasz

    2016-04-01

    Satellites orbiting around Earth are affected by gravitational forces and non-gravitational perturbations (NGP). While the perturbations caused by gravitational forces, which are due to central body gravity (including high-precision geopotential field) and its changes (due to secular variations and tides), solar bodies attraction and relativistic effects are well-modeled, the perturbations caused by the non-gravitational forces are the most limiting factor in Precise Orbit Determination (POD). In this work we focused on very precise non-gravitational force modeling for medium Earth orbit satellites by applying the various models of solar radiation pressure including changes in solar irradiance and Earth/Moon shadow transition, Earth albedo and thermal radiation. For computing influence of aforementioned forces on spacecraft the analytical box-wing satellite model was applied. Smaller effects like antenna thrust or spacecraft thermal radiation were also included. In the process of orbit determination we compared the orbit with analytically computed NGP with the standard procedure in which CODE model is fitted for NGP recovery. We considered satellites from several systems and on different orbits and for different periods: when the satellite is all the time in full sunlight and when transits the umbra and penumbra regions.

  13. Precise determination of seawater calcium using isotope dilution inductively coupled plasma mass spectrometry.

    PubMed

    Liu, Hou-Chun; You, Chen-Feng; Cai, Wei-Jun; Chung, Chuan-Hsiung; Huang, Kuo-Fang; Chen, Bao-Shan; Li, Yen

    2014-02-21

    We describe a method for rapid, precise and accurate determination of calcium ion (Ca(2+)) concentration in seawater using isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS). A 10 μL aliquot of seawater was spiked with an appropriate (43)Ca enriched solution for (44)Ca/(43)Ca ID-ICP-MS analyses, using an Element XR (Thermo Fisher Scientific), operated at low resolution in E-scan acquisition mode. A standard-sample bracketing technique was applied to correct for potential mass discrimination and ratio drift at every 5 samples. A precision of better than 0.05% for within-run and 0.10% for duplicate measurements of the IAPSO seawater standard was achieved using 10 μL solutions with a measuring time less than 3 minutes. Depth profiles of seawater samples collected from the Arctic Ocean basin were processed and compared with results obtained by the classic ethylene glycol tetra-acetic acid (EGTA) titration. Our new ID-ICP-MS data agreed closely with the conventional EGTA data, with the latter consistently displaying 1.5% excess Ca(2+) values, possibly due to a contribution of interference from Mg(2+) and Sr(2+) in the EGTA titration. The newly obtained Sr/Ca profiles reveal sensitive water mass mixing in the upper oceanic column to reflect ice melting in the Arctic region. This novel technique provides a tool for seawater Ca(2+) determination with small sample size, high throughput, excellent internal precision and external reproducibility.

  14. Precise determination of the 235U reactor antineutrino cross section per fission

    NASA Astrophysics Data System (ADS)

    Giunti, C.

    2017-01-01

    We investigate which among the reactor antineutrino fluxes from the decays of the fission products of 235U, 238U, 239Pu, and 241Pu may be responsible for the reactor antineutrino anomaly if the anomaly is due to a miscalculation of the antineutrino fluxes. We find that it is very likely that at least the calculation of the 235U flux must be revised. From the fit of the data we obtain the precise determination σ235 = (6.33 ± 0.08) ×10-43cm2 /fission of the 235U cross section per fission, which is more precise than the calculated value and differs from it by 2.2σ. The cross sections per fission of the other fluxes have large uncertainties and in practice their values are undetermined by the fit.

  15. Precise determination of the 113Cd fourth-forbidden non-unique β -decay Q value

    NASA Astrophysics Data System (ADS)

    Gamage, N. D.; Bollen, G.; Eibach, M.; Gulyuz, K.; Izzo, C.; Kandegedara, R. M. E. B.; Redshaw, M.; Ringle, R.; Sandler, R.; Valverde, A. A.

    2016-08-01

    Using Penning trap mass spectrometry, we have performed a precise determination of the Q value for the highly forbidden β decay of 113Cd. An independent measurement of the Q value fixes the end-point energy in a fit to the 113Cdβ -decay spectrum. This provides a strong test of systematics for detectors that have observed this decay, such as those developed for β β -decay searches in cadmium and other isotopes. It will also aid in the theoretical description of the β -decay spectrum. The result, Qβ=323.89 (27 ) keV , agrees at the 1.3 σ level with the value obtained from the 2012 Atomic Mass Evaluation [Chin. Phys. C 36, 1603 (2012), 10.1088/1674-1137/36/12/003], but is a factor of almost four more precise. We also report improved values for the atomic masses of 113Cd,113In, and 112Cd.

  16. Determination of the half-life of 213Fr with high precision

    NASA Astrophysics Data System (ADS)

    Fisichella, M.; Musumarra, A.; Farinon, F.; Nociforo, C.; Del Zoppo, A.; Figuera, P.; La Cognata, M.; Pellegriti, M. G.; Scuderi, V.; Torresi, D.; Strano, E.

    2013-07-01

    High-precision measurement of half-life and Qα value of neutral and highly charged α emitters is a major subject of investigation currently. In this framework, we recently pushed half-life measurements of neutral emitters to a precision of a few per mil. This result was achieved by using different techniques and apparatuses at Istituto Nazionale di Fisica Nucleare Laboratori Nazionali del Sud (INFN-LNS) and GSI Darmstadt. Here we report on 213Fr half-life determination [T1/2(213Fr) = 34.14±0.06 s] at INFN-LNS, detailing the measurement protocol used. Direct comparison with the accepted value in the literature shows a discrepancy of more than three sigma. We propose this new value as a reference, discussing previous experiments.

  17. Determination of precise crystallographic directions for mask alignment in wet bulk micromachining for MEMS

    NASA Astrophysics Data System (ADS)

    Singh, Sajal Sagar; Pal, Prem; Pandey, Ashok Kumar; Xing, Yan; Sato, Kazuo

    2016-12-01

    In wet bulk micromachining, the etching characteristics are orientation dependent. As a result, prolonged etching of mask openings of any geometric shape on both Si{100} and Si{110} wafers results in a structure defined by the slowest etching planes. In order to fabricate microstructures with high dimensional accuracy, it is vital to align the mask edges along the crystal directions comprising of these slowest etching planes. Thus, precise alignment of mask edges is important in micro/nano fabrication. As a result, the determination of accurate crystal directions is of utmost importance and is in fact the first step to ensure dimensionally accurate microstructures for improved performance. In this review article, we have presented a comprehensive analysis of different techniques to precisely determine the crystallographic directions. We have covered various techniques proposed in the span of more than two decades to determine the crystallographic directions on both Si{100} and Si{110} wafers. Apart from a detailed discussion of each technique along with their design and implementation, we have provided a critical analysis of the associated constraints, benefits and shortcomings. We have also summed up the critical aspects of each technique and presented in a tabular format for easy reference for readers. This review article comprises of an exhaustive discussion and is a handy reference for researchers who are new in the field of wet anisotropic etching or who want to get abreast with the techniques of determination of crystal directions.

  18. High-precision determination of iron oxidation state in silicate glasses using XANES

    SciTech Connect

    Cottrell, Elizabeth; Kelley, Katherine A.; Lanzirotti, Antonio; Fischer, Rebecca A.

    2009-11-04

    Fe K-edge X-ray absorption near-edge structure (XANES) and Moessbauer spectra were collected on natural basaltic glasses equilibrated over a range of oxygen fugacity (QFM - 3.5 to QFM + 4.5). The basalt compositions and fO{sub 2} conditions were chosen to bracket the natural range of redox conditions expected for basalts from mid-ocean ridge, ocean island, back-arc basin, and arc settings, in order to develop a high-precision calibration for the determination of Fe{sup 3+}/{Sigma}Fe in natural basalts. The pre-edge centroid energy, corresponding to the 1s {yields} 3d transition, was determined to be the most robust proxy for Fe oxidation state, affording significant advantages compared to the use of other spectral features. A second-order polynomial models the correlation between the centroid and Fe{sup 3+}/{Sigma}Fe, yielding a precision of {+-} 0.0045 in Fe{sup 3+}/{Sigma}Fe for glasses with Fe{sup 3+}/{Sigma}Fe > 8%, which is comparable to the precision of wet chemistry. This high precision relies on a Si (311) monochromator to better define the Fe{sup 2+} and Fe{sup 3+} transitions, accurate and robust modeling of the pre-edge feature, dense fO{sub 2}-coverage and compositional appropriateness of reference glasses, and application of a non-linear drift correction. Through re-analysis of the reference glasses across three synchrotron beam sessions, we show that the quoted precision can be achieved (i.e., analyses are reproducible) across multiple synchrotron beam sessions, even when spectral collection conditions (detector parameters or sample geometry) change. Rhyolitic glasses were also analyzed and yield a higher centroid energy at a given Fe{sup 3+}/{Sigma}Fe than basalts, implying that major variations in melt structure affect the relationship between centroid position and Fe{sup 3+}/{Sigma}Fe, and that separate calibrations are needed for the determination of oxidation state in basalts and rhyolites.

  19. The high-precision videometrics methods to determining absolute vertical benchmark

    NASA Astrophysics Data System (ADS)

    Liu, Jinbo; Zhu, Zhaokun

    2013-01-01

    The mobile measurement equipment plays an important role in engineering measurement tasks and its measuring device is fixed with the vehicle platform. Therefore, how to correct the measured error in time that caused by swayed platform is a basic problem. Videometrics has its inherent advantages in solving this problem. First of all, videometrics technology is non-contact measurement, which has no effect on the target's structural characteristics and motion characteristics. Secondly, videometrics technology has high precision especially for surface targets and linear targets in the field of view. Thirdly, videometrics technology has the advantages of automatic, real-time and dynamic. This paper is mainly for mobile theodolite.etc that works under the environment of absolute vertical benchmark and proposed two high-precision methods to determine vertical benchmark: Direct-Extracting, which is based on the intersection of plats under the help of two cameras; Benchmark-Transformation, which gets the vertical benchmark by reconstructing the level-plat. Two methods both have the precision of under 10 seconds by digital simulation and physical experiments. The methods proposed by this paper have significance both on the theory and application.

  20. A demonstration of high precision GPS orbit determination for geodetic applications

    NASA Technical Reports Server (NTRS)

    Lichten, S. M.; Border, J. S.

    1987-01-01

    High precision orbit determination of Global Positioning System (GPS) satellites is a key requirement for GPS-based precise geodetic measurements and precise low-earth orbiter tracking, currently under study at JPL. Different strategies for orbit determination have been explored at JPL with data from a 1985 GPS field experiment. The most successful strategy uses multi-day arcs for orbit determination and includes fine tuning of spacecraft solar pressure coefficients and station zenith tropospheric delays using the GPS data. Average rms orbit repeatability values for 5 of the GPS satellites are 1.0, 1.2, and 1.7 m in altitude, cross-track, and down-track componenets when two independent 5-day fits are compared. Orbit predictions up to 24 hours outside the multi-day arcs agree within 4 m of independent solutions obtained with well tracked satellites in the prediction interval. Baseline repeatability improves with multi-day as compared to single-day arc orbit solutions. When tropospheric delay fluctuations are modeled with process noise, significant additional improvement in baseline repeatability is achieved. For a 246-km baseline, with 6-day arc solutions for GPS orbits, baseline repeatability is 2 parts in 100 million (0.4-0.6 cm) for east, north, and length components and 8 parts in 100 million for the vertical component. For 1314 and 1509 km baselines with the same orbits, baseline repeatability is 2 parts in 100 million for the north components (2-3 cm) and 4 parts in 100 million or better for east, length, and vertical components.

  1. Precision determination of invisible-particle masses at the CERN LHC

    NASA Astrophysics Data System (ADS)

    Barr, Alan J.; Ross, Graham G.; Serna, Mario

    2008-09-01

    We develop techniques to determine the mass scale of invisible particles pair-produced at hadron colliders. We employ the constrained mass variable m2C, which provides an event-by-event lower bound to the mass scale given a mass difference. We complement this variable with a new variable m2C,UB which provides an additional upper bound to the mass scale and demonstrate its utility with a realistic case study of a supersymmetry model. These variables together effectively quantify the “kink” in the function max mT2 which has been proposed as a mass-determination technique for collider-produced dark matter. An important advantage of the m2C method is that it does not rely simply on the position at the end point, but it uses the additional information contained in events which lie far from the end point. We found the mass by comparing the HERWIG generated m2C distribution to ideal distributions for different masses. We find that for the case studied, with 100fb-1 of integrated luminosity (about 400 signal events), the invisible particle’s mass can be measured to a precision of 4.1 GeV. We conclude that this technique’s precision and accuracy is as good as, if not better than, the best known techniques for invisible-particle mass determination at hadron colliders.

  2. Improved treatment of global positioning system force parameters in precise orbit determination applications

    NASA Technical Reports Server (NTRS)

    Vigue, Y.; Lichten, S. M.; Muellerschoen, R. J.; Blewitt, G.; Heflin, M. B.

    1993-01-01

    Data collected from a worldwide 1992 experiment were processed at JPL to determine precise orbits for the satellites of the Global Positioning System (GPS). A filtering technique was tested to improve modeling of solar-radiation pressure force parameters for GPS satellites. The new approach improves orbit quality for eclipsing satellites by a factor of two, with typical results in the 25- to 50-cm range. The resultant GPS-based estimates for geocentric coordinates of the tracking sites, which include the three DSN sites, are accurate to 2 to 8 cm, roughly equivalent to 3 to 10 nrad of angular measure.

  3. Quantitation and structures of oligosaccharide chains in human trachea mucin glycoproteins.

    PubMed

    Sangadala, S; Bhat, U R; Mendicino, J

    1992-12-02

    Human respiratory mucin glycoproteins from patients with cystic fibrosis were purified and oligosaccharide chains were released by treatment with alkaline borohydride. A neutral oligosaccharide alditol fraction was isolated from mucin obtained from a patient with A blood group determinant by chromatography on DEAE-cellulose and individual oligosaccharide chains were then isolated by gel filtration on BioGel P-6 columns and high performance liquid chromatography with gradient and isocratic solvent systems. The structures of the purified oligosaccharides were determined by methylation analysis, sequential glycosidase digestion and 'H-NMR spectroscopy. The amount of each chain was determined by compositional analysis. A wide array of discrete branched oligosaccharide structures that contain from 3 to 22 sugar residues were found. Many of the oligosaccharides are related and appear to be precursors of larger chains. The predominant branched oligosaccharides which accumulate contain terminal blood group H (Fuc alpha 2Ga1 beta 4) or blood group A (Fuc alpha 2(Ga1NAc alpha 3) (Ga1 beta 4) determinants which stop further branching and chain elongation. The elongation of oligosaccharide chains in respiratory mucins occurs on the beta 3-linked G1cNAc at branch points, whereas the beta 6-linked G1cNAc residue ultimately forms short side chains with a Fuc alpha 2(Ga1NAc alpha 3) Ga1 beta 4 G1cNAc beta 6 structure in individuals with A blood group determinant. The results obtained in the current studies further suggest that even higher molecular weight oligosaccharide chains with analogous branched structures are present in some human respiratory mucin glycoproteins. Increasing numbers of the repeating sequence shown in the oligosaccharide below is present in the higher molecular weight chains. [formula: see text] This data in conjunction with our earlier observations on the extensive branching of these oligosaccharide chains helps to define and explain the enormous range of

  4. Inulin Potential for Enzymatic Obtaining of Prebiotic Oligosaccharides.

    PubMed

    Flores, Adriana C; Morlett, Jesús A; Rodríguez, Raúl

    2016-08-17

    Oligosaccharides have been marketed since the 80s as low-calorie agents and recently have gained interest in the pharmaceutical and food industry as functional sweeteners and prebiotic enriching population of Bifidobacteria. Currently, they have an approximated value of $200 per kg and recently, inulin has been proposed as a feedstock for production of oligosaccharides through selective hydrolysis by action of endoinulinase. High optimum temperature (60°C) and thermostability are two important criteria that determine suitability of this enzyme for industrial applications as well as enzyme cost, a major limiting factor. Significant reduction in cost can be achieved by employing low-value and abundant inulin-rich plants as Jerusalem artichoke, dahlia, yacon, garlic, and onion, among others. In general, the early harvested tubers of these plants contain a greater amount of highly polymerized sugar fractions, which offer more industrial value than late-harvested tubers or those after storage. Also, development of recombinant microorganisms could be useful to reduce the cost of enzyme technology for large-scale production of oligosaccharides. In the case of fungal inulinases, several studies of cloning and modification have been made to achieve greater efficiency. The present paper reviews inulin from vegetable sources as feedstock for oligosaccharides production through the action of inulinases, the impact of polymerization degree of inulin and its availability, and some strategies to increase oligosaccharide production.

  5. High-precision laser-assisted absolute determination of x-ray diffraction angles

    SciTech Connect

    Kubicek, K.; Braun, J.; Bruhns, H.; Crespo Lopez-Urrutia, J. R.; Mokler, P. H.; Ullrich, J.

    2012-01-15

    A novel technique for absolute wavelength determination in high-precision crystal x-ray spectroscopy recently introduced has been upgraded reaching unprecedented accuracies. The method combines visible laser beams with the Bond method, where Bragg angles ({theta} and -{theta}) are determined without any x-ray reference lines. Using flat crystals this technique makes absolute x-ray wavelength measurements feasible even at low x-ray fluxes. The upgraded spectrometer has been used in combination with first experiments on the 1s2p {sup 1}P{sub 1}{yields} 1s{sup 2} {sup 1}S{sub 0} w-line in He-like argon. By resolving a minute curvature of the x-ray lines the accuracy reaches there the best ever reported value of 1.5 ppm. The result is sensitive to predicted second-order QED contributions at the level of two-electron screening and two-photon radiative diagrams and will allow for the first time to benchmark predicted binding energies for He-like ions at this level of precision.

  6. A demonstration of sub-meter GPS orbit determination and high precision user positioning

    NASA Technical Reports Server (NTRS)

    Bertiger, Willy I.; Lichten, Stephen M.; Katsigris, Eugenia C.

    1988-01-01

    It was demonstrated that the submeter GPS (Global Positioning System) orbits can be determined using multiday arc solutions with the current GPS constellation subset visible for about 8 h each day from North America. Submeter orbit accuracy was shown through orbit repeatability and orbit prediction. North American baselines of 1000-2000 km length can be estimated simultaneously with the GPS orbits to an accuracy of better than 1.5 parts in 108 (3 cm over 2000 km distance) with a daily precision of two parts in 108 or better. The most reliable baseline solutions are obtained using the same type of receivers and antennas at each end of the baseline. Baselines greater than 1000 km distance from Florida to sites in the Caribbean region have also been determined with daily precision of 1-4 parts in 108. The Caribbean sites are located well outside the fiducial tracking network and the region of optimal GPS common visibility. Thus, these results further demonstrate the robustness of the multiday arc GPS orbit solutions.

  7. A proposed experimental method for interpreting Doppler effect measurements and determining their precision

    NASA Technical Reports Server (NTRS)

    Klann, P. G.

    1973-01-01

    The principal problem in the measurement of the Doppler reactivity effect is separating it from the thermal reactivity effects of the expansion of the heated sample. It is shown in this proposal that the thermal effects of sample expansion can be experimentally determined by making additional measurements with porous samples having the same mass and/or volume as the primary sample. By combining these results with independent measurements of the linear temperature coefficient and the computed temperature dependence of the Doppler coefficient the magnitude of the Doppler coefficient may be extracted from the data. These addiational measurements are also useful to experimentally determine the precision of the reactivity oscillator technique used to measure the reactivity effects of the heated sample.

  8. Robust Flight Path Determination for Mars Precision Landing Using Genetic Algorithms

    NASA Technical Reports Server (NTRS)

    Bayard, David S.; Kohen, Hamid

    1997-01-01

    This paper documents the application of genetic algorithms (GAs) to the problem of robust flight path determination for Mars precision landing. The robust flight path problem is defined here as the determination of the flight path which delivers a low-lift open-loop controlled vehicle to its desired final landing location while minimizing the effect of perturbations due to uncertainty in the atmospheric model and entry conditions. The genetic algorithm was capable of finding solutions which reduced the landing error from 111 km RMS radial (open-loop optimal) to 43 km RMS radial (optimized with respect to perturbations) using 200 hours of computation on an Ultra-SPARC workstation. Further reduction in the landing error is possible by going to closed-loop control which can utilize the GA optimized paths as nominal trajectories for linearization.

  9. High precision momentum calibration of the magnetic spectrometers at MAMI for hypernuclear binding energy determination

    NASA Astrophysics Data System (ADS)

    Margaryan, A.; Annand, J. R. M.; Achenbach, P.; Ajvazyan, R.; Elbakyan, H.; Montgomery, R.; Nakamura, S. N.; Pochodzalla, J.; Schulz, F.; Toyama, Y.; Zhamkochyan, S.

    2017-02-01

    We propose a new method for absolute momentum calibration of magnetic spectrometers used in nuclear physics, using the time-of-flight (TOF) differences of pairs of particles with different masses. In cases where the flight path is not known, a calibration can be determined by using the TOF differences of two pair combinations of three particles. A Cherenkov detector, read out by a radio frequency photomultiplier tube, is considered as the high-resolution and highly stable TOF detector. By means of Monte Carlo simulations it is demonstrated that the magnetic spectrometers at the MAMI electron-scattering facility can be calibrated absolutely with an accuracy δp / p ≤10-4 , which will be crucial for high precision determination of hypernuclear masses.

  10. Repeated Sampling to Determine the Precision of Estimating Nematode Population Densities

    PubMed Central

    Schmitt, D. P.; Barker, K. R.; Noe, J. P.; Koenning, S. R.

    1990-01-01

    The first phase of this study involved repeated samplings of five fields using composite samples of 10, 20, 40, and 80 soil cores, to determine the precision of nematode assays. The second phase focused on randomly selecting two and four 2-ha subunits (data on Meloidogyne spp.) of 24 fields ranging from 6 to 40 ha and computing the precision of estimated means for these numbers ofsubunits versus the general field mean (based on all 2-ha subunits). Average numbers of nematodes from most samples containing Meloidogyne spp., Heterodera glycines, Helicotylenchus dihystera, Scutellonema brachyurum, and (or) Hoplolaimus galeatus were within 50% of the overall means. Coefficient of variation (CV) values were generally lower for 40 cores than for 10, 20, and 80 cores per sample. When data for all nematodes and fields were combined, this value was lowest for 40 and 80 cores. The CV values were higher for Meloidogyne spp. than for H. glycines. Means of two samplings increased the probability of obtaining numbers nearer the mean for that field than numbers from a single composite sample. For the second phase, population estimates of Meloidogyne spp. based on four 2-ha subunits generally were closer to field means than were those for two subunits. Sampling precision with these subunits diminished greatly in large fields with variable soils and (or) mixed cropping histories. Either two or four subunits gave population estimates within 3-20% of the field mean in most instances. The mean man hours required for sampling ca. 2-ha parcels of 4-20-ha fields was 0.54 hours. PMID:19287757

  11. Precision Orbit Determination for the Lunar Reconnaissance Orbiter: orbit quality and gravity field estimation

    NASA Astrophysics Data System (ADS)

    Mazarico, E.; Rowlands, D. D.; Neumann, G. A.; Lemoine, F. G.; Torrence, M. H.; Smith, D. E.; Zuber, M. T.; Mao, D.

    2010-12-01

    We present results of the Precision Orbit Determination work undertaken by the Lunar Orbiter Laser Altimeter (LOLA) Science Team for the Lunar Reconnaissance Orbiter (LRO) mission, in order to meet the position knowledge accuracy requirements (50-m total position) and to precisely geolocate the LRO datasets. In addition to the radiometric tracking data, one-way laser ranges (LR) between Earth stations and the spacecraft are made possible by a small telescope mounted on the spacecraft high-gain antenna. The photons received from Earth are transmitted to one LOLA detector by a fiber optics bundle. The LOLA timing system enables 5-s LR normal points with precision better than 10cm. Other types of geodetic constraints are derived from the altimetric data itself. The orbit geometry can be constrained at the times of laser groundtrack intersections (crossovers). Due to the Moon's slow rotation, orbit solutions and normal equations including altimeter crossovers are processed and created in one month batches. Recent high-resolution topographic maps near the lunar poles are used to produce a new kind of geodetic constraints. Purely geometric, those do not necessitate actual groundtrack intersections. We assess the contributions of those data types, and the quality of our orbits. Solutions which use altimetric crossover meet the horizontal 50-m requirement, and perform usually better (10-20m). We also obtain gravity field solutions based on LRO and historical data. The various LRO data are accumulated into normal equations, separately for each one month batch and for each measurement type, which enables the final weights to be adjusted during the least-squares inversion step. Expansion coefficients to degree and order 150 are estimated, and a Kaula rule is still needed to stabilize the farside field. The gravity field solutions are compared to previous solutions (GLGM-3, LP150Q, SGM100h) and the geopotential predicted from the latest LOLA spherical harmonic expansion.

  12. Evaluation of precision estimates for fiber-dimensional and electrical hygrometers for water activity determinations.

    PubMed

    Stroup, W H; Peeler, J T; Smith, K

    1987-01-01

    The precision of instruments used in 3 collaborative studies conducted within the Food and Drug Administration over a 4-year period (1981, 1982, 1984) for water activity (aw) determinations according to the official AOAC method is evaluated. Calibration responses of the instruments were tested for linearity over the aw range from 0.75 to 0.97. Average absolute percent difference between predicted and assigned aw values for the linear model ranged from 0.3 to 0.7% for a fiber-dimensional hygrometer (Abbeon) and 3 electrical hygrometers (Beckman, Rotronics, and Weather Measure). The calibration responses for another electrical hygrometer (Hygrodynamics) were nonlinear. The fiber-dimensional hygrometer yielded mean aw values and precision estimates that did not differ significantly from those obtained with the electrical hygrometers for (NH4)2SO4slush, KNO3 slush, sweetened condensed milk, pancake syrup, and cheese spread. However, the mean aw value for a soy sauce was 0.838 for the electrical hygrometers compared with 0.911 for the fiber-dimensional hygrometer. The fiber-dimensional hygrometer was affected by a volatile component(s) in the soy sauce that caused an erroneously high aw value. Pooled estimates of reproducibility (Sx) in the 3 studies were 0.008 for the fiber-dimensional hygrometer and 0.010 for the electrical hygrometers; these values were not significantly different from those reported in the study that verified the current official AOAC method.

  13. Precise determination of the heat delivery during in vivo magnetic nanoparticle hyperthermia with infrared thermography.

    PubMed

    Rodrigues, Harley; Capistrano, Gustavo; Mello, Francyelli; Zufelato, Nicholas; Silveira-Lacerda, Elisangela; Bakuzis, Andris F

    2017-03-17

    Monitoring noninvasively and in real-time the heat delivery during magnetic nanoparticle hyperthermia is of fundamental importance to predict clinical outcome for cancer treatment. Infrared thermography (IRT) can inform the surface temperature due to three-dimensional heat delivery inside a subcutaneous tumor, an argument that is supported by numerical simulations. However, for precise temperature determination, it is of crucial relevance to use a correct experimental configuration. This work reports a magnetic nanoparticle hyperthermia study (MNH) using a sarcoma 180 murine tumor containing 3.9 mg of intratumorally injected manganese-ferrite nanoparticles. MNH was performed at low field amplitude and nonuniform field configuration. Five 30-minute in vivo magnetic hyperthermia experiments were performed, monitoring the surface temperature with fibre optical sensor and thermal camera at distinct angles with respect to the animal surface. The results indicate that temperature errors as huge as 7^{o}C can occur if the experiment is not properly designed. A new IRT error model is found to explain the data. More importantly, it is shown how to precisely monitor temperature with IRT during hyperthermia, which could positively impact heat dosimetry and clinical planning.

  14. Precise orbit determination of a maneuvered GEO satellite using CAPS ranging data

    NASA Astrophysics Data System (ADS)

    Huang, Yong; Hu, Xiaogong; Huang, Cheng; Yang, Qiangwen; Jiao, Wenhai

    2009-03-01

    Wheel-off-loadings and orbital maneuvers of the GEO satellite result in additional accelerations to the satellite itself. Complex and difficult to model, these time varying accelerations are an important error source of precise orbit determination (POD). In most POD practices, only non-maneuver orbital arcs are treated. However, for some applications such as satellite navigation RDSS services, uninterrupted orbital ephemeris is demanded, requiring the development of POD strategies to be processed both during and after an orbital maneuver. We in this paper study the POD for a maneuvered GEO satellite, using high precision and high sampling rate ranging data obtained with Chinese Area Positioning System (CAPS). The strategy of long arc POD including maneuver arcs is studied by using telemetry data to model the maneuver thrust process. Combining the thrust and other orbital perturbations, a long arc of 6 days’ CAPS ranging data is analyzed. If the telemetry data are not available or contain significant errors, attempts are made to estimate thrusting parameters using CAPS ranging data in the POD as an alternative to properly account for the maneuver. Two strategies achieve reasonably good data fitting level in the tested arc with the maximal position difference being about 20 m.

  15. Precise Determination of the Lyman-1 Transition Energy in Hydrogen-like Gold Ions with Microcalorimeters

    NASA Astrophysics Data System (ADS)

    Kraft-Bermuth, S.; Andrianov, V.; Bleile, A.; Echler, A.; Egelhof, P.; Grabitz, P.; Kilbourne, C.; Kiselev, O.; McCammon, D.; Scholz, P.

    2014-09-01

    The precise determination of the transition energy of the Lyman-1 line in hydrogen-like heavy ions provides a sensitive test of quantum electrodynamics in very strong Coulomb fields. We report the determination of the Lyman-1 transition energy of gold ions (Au) with microcalorimeters at the experimental storage ring at GSI. X-rays produced by the interaction of 125 MeV/u Au ions with an internal argon gas-jet target were detected. The detector array consisted of 14 pixels with silicon thermistors and Sn absorbers, for which an energy resolution of 50 eV for an X-ray energy of 59.5 keV was obtained in the laboratory. The Lyman-1 transition energy was determined for each pixel in the laboratory frame, then transformed into the emitter frame and averaged. A Dy-159 source was used for energy calibration. The absolute positions of the detector pixels, which are needed for an accurate correction of the Doppler shift, were determined by topographic measurements and by scanning a collimated Am-241 source across the cryostat window. The energy of the Lyman-1 line in the emitter frame is eV, in good agreement with theoretical predictions. The systematic error is dominated by the uncertainty in the position of the cryostat relative to the interaction region of beam and target.

  16. Oligosaccharides from Sucrose via Glycansucrases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glycansucrases are a class of microbial enzymes that polymerize either the fructosyl or the glucosyl moiety of sucrose to give beta-D-fructans or alpha-D-glucans. They are also capable of transferring fructosyl or glucosyl units to acceptor molecules to yield oligosaccharides. Although the glycosy...

  17. Sugar loss and enzyme inhibition due to oligosaccharide accumulation during high solids-loading enzymatic hydrolysis

    DOE PAGES

    Xue, Saisi; Uppugundla, Nirmal; Bowman, Michael J.; ...

    2015-11-26

    inhibitory effects of oligosaccharides on commercial enzymes. In conclusion, the carbohydrate composition of the recalcitrant oligosaccharides, ratios of different DP oligomers and their distribution profiles were determined. Recalcitrance and enzyme inhibition studies help determine whether the commercial enzyme mixtures lack the enzyme activities required to completely de-polymerize the plant cell wall. Such studies clarify the reasons for oligosaccharide accumulation and contribute to strategies by which oligosaccharides can be converted into fermentable sugars and provide higher biofuel yields with less enzyme.« less

  18. Sugar loss and enzyme inhibition due to oligosaccharide accumulation during high solids-loading enzymatic hydrolysis

    SciTech Connect

    Xue, Saisi; Uppugundla, Nirmal; Bowman, Michael J.; Cavalier, David; Da Costa Sousa, Leonardo; Dale, Bruce E.; Balan, Venkatesh

    2015-11-26

    inhibitory effects of oligosaccharides on commercial enzymes. In conclusion, the carbohydrate composition of the recalcitrant oligosaccharides, ratios of different DP oligomers and their distribution profiles were determined. Recalcitrance and enzyme inhibition studies help determine whether the commercial enzyme mixtures lack the enzyme activities required to completely de-polymerize the plant cell wall. Such studies clarify the reasons for oligosaccharide accumulation and contribute to strategies by which oligosaccharides can be converted into fermentable sugars and provide higher biofuel yields with less enzyme.

  19. A Comparison of TOPEX/Poseidon TDRESS-based Operational Orbit Determination Results with the Precision Orbit Ephemeris

    NASA Technical Reports Server (NTRS)

    Frauenholz, R. B.; Bhat, R. S.; Shapiro, B. E.; Leavitt, R. K.

    1998-01-01

    Since its' launch on August 10, 1992, the TOPEX/Poseidon satellite hs successfully observed the earth's ocean circulation using a combination of precision orbit determination (POD) and dual-frequency radar altimetry.

  20. Advanced application flight experiments precision attitude determination system. Volume 2: System tests

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The performance capability of each of two precision attitude determination systems (PADS), one using a strapdown star tracker, and the other using a single-axis gimbal star tracker was measured in the laboratory under simulated orbit conditions. The primary focus of the evaluation was on the contribution to the total system accuracy by the star trackers, and the effectiveness of the software algorithms in functioning with actual sensor signals. A brief description of PADS, the laboratory test configuration and the test facility, is given along with a discussion of the data handling and display, laboratory computer programs, PADS performance evaluation programs, and the strapdown and gimbal system tests. Results are presented and discussed.

  1. High-Precision Determination of the Pion-Nucleon σ Term from Roy-Steiner Equations

    NASA Astrophysics Data System (ADS)

    Hoferichter, Martin; Ruiz de Elvira, Jacobo; Kubis, Bastian; Meißner, Ulf-G.

    2015-08-01

    We present a determination of the pion-nucleon (π N ) σ term σπ N based on the Cheng-Dashen low-energy theorem (LET), taking advantage of the recent high-precision data from pionic atoms to pin down the π N scattering lengths as well as of constraints from analyticity, unitarity, and crossing symmetry in the form of Roy-Steiner equations to perform the extrapolation to the Cheng-Dashen point in a reliable manner. With isospin-violating corrections included both in the scattering lengths and the LET, we obtain σπ N=(59.1 ±1.9 ±3.0 ) MeV =(59.1 ±3.5 ) MeV , where the first error refers to uncertainties in the π N amplitude and the second to the LET. Consequences for the scalar nucleon couplings relevant for the direct detection of dark matter are discussed.

  2. Invited Article: A precise instrument to determine the Planck constant, and the future kilogram.

    PubMed

    Haddad, D; Seifert, F; Chao, L S; Li, S; Newell, D B; Pratt, J R; Williams, C; Schlamminger, S

    2016-06-01

    A precise instrument, called a watt balance, compares mechanical power measured in terms of the meter, the second, and the kilogram to electrical power measured in terms of the volt and the ohm. A direct link between mechanical action and the Planck constant is established by the practical realization of the electrical units derived from the Josephson and the quantum Hall effects. We describe in this paper the fourth-generation watt balance at the National Institute of Standards and Technology (NIST), and report our initial determination of the Planck constant obtained from data taken in late 2015 and the beginning of 2016. A comprehensive analysis of the data and the associated uncertainties led to the SI value of the Planck constant, h = 6.626 069 83(22) × 10(-34) J s. The relative standard uncertainty associated with this result is 34 × 10(-9).

  3. Precise Orbit Determination for LEO Spacecraft Using GNSS Tracking Data from Multiple Antennas

    NASA Technical Reports Server (NTRS)

    Kuang, Da; Bertiger, William; Desai, Shailen; Haines, Bruce

    2010-01-01

    To support various applications, certain Earth-orbiting spacecrafts (e.g., SRTM, COSMIC) use multiple GNSS antennas to provide tracking data for precise orbit determination (POD). POD using GNSS tracking data from multiple antennas poses some special technical issues compared to the typical single-antenna approach. In this paper, we investigate some of these issues using both real and simulated data. Recommendations are provided for POD with multiple GNSS antennas and for antenna configuration design. The observability of satellite position with multiple antennas data is compared against single antenna case. The impact of differential clock (line biases) and line-of-sight (up, along-track, and cross-track) on kinematic and reduced-dynamic POD is evaluated. The accuracy of monitoring the stability of the spacecraft structure by simultaneously performing POD of the spacecraft and relative positioning of the multiple antennas is also investigated.

  4. Analytical methodology for determination of helicopter IFR precision approach requirements. [pilot workload and acceptance level

    NASA Technical Reports Server (NTRS)

    Phatak, A. V.

    1980-01-01

    A systematic analytical approach to the determination of helicopter IFR precision approach requirements is formulated. The approach is based upon the hypothesis that pilot acceptance level or opinion rating of a given system is inversely related to the degree of pilot involvement in the control task. A nonlinear simulation of the helicopter approach to landing task incorporating appropriate models for UH-1H aircraft, the environmental disturbances and the human pilot was developed as a tool for evaluating the pilot acceptance hypothesis. The simulated pilot model is generic in nature and includes analytical representation of the human information acquisition, processing, and control strategies. Simulation analyses in the flight director mode indicate that the pilot model used is reasonable. Results of the simulation are used to identify candidate pilot workload metrics and to test the well known performance-work-load relationship. A pilot acceptance analytical methodology is formulated as a basis for further investigation, development and validation.

  5. High precision mapping of kidney stones using μ-IR spectroscopy to determine urinary lithogenesis.

    PubMed

    Blanco, Francisco; Ortiz-Alías, Pilar; López-Mesas, Montserrat; Valiente, Manuel

    2015-06-01

    Evolution of urinary lithiasis is determined by the metabolism and life-style of the related patient. The appropriate classification of the stone is mandatory for the identification of the lithogenic process. In this study, cros-sections from a single stone of each of the most frequent urolithiasis types (calcium oxalate mono and dihydrate and carbonate apatite) have been selected and imaged using IR microspectroscopy. Moreover, the use of high definition sFTIR (synchrotron source) has revealed hidden information to the conventional FTIR. This work has demonstrated that minor components become key factors on the description of the stages of stone formation. Intensity map for COM (1630 cm(-1) peak). The high spatial definition achieved is key for the precise description of the kidney stone history.

  6. Invited Article: A precise instrument to determine the Planck constant, and the future kilogram

    NASA Astrophysics Data System (ADS)

    Haddad, D.; Seifert, F.; Chao, L. S.; Li, S.; Newell, D. B.; Pratt, J. R.; Williams, C.; Schlamminger, S.

    2016-06-01

    A precise instrument, called a watt balance, compares mechanical power measured in terms of the meter, the second, and the kilogram to electrical power measured in terms of the volt and the ohm. A direct link between mechanical action and the Planck constant is established by the practical realization of the electrical units derived from the Josephson and the quantum Hall effects. We describe in this paper the fourth-generation watt balance at the National Institute of Standards and Technology (NIST), and report our initial determination of the Planck constant obtained from data taken in late 2015 and the beginning of 2016. A comprehensive analysis of the data and the associated uncertainties led to the SI value of the Planck constant, h = 6.626 069 83(22) × 10-34 J s. The relative standard uncertainty associated with this result is 34 × 10-9.

  7. Precision Determination of the Small-x Gluon from Charm Production at LHCb

    NASA Astrophysics Data System (ADS)

    Gauld, Rhorry; Rojo, Juan

    2017-02-01

    The small-x gluon in global fits of parton distributions is affected by large uncertainties from the lack of direct experimental constraints. In this Letter, we provide a precision determination of the small-x gluon from the exploitation of forward charm production data provided by LHCb for three different center-of-mass (c.m.) energies: 5 TeV, 7 TeV, and 13 TeV. The LHCb measurements are included in the parton distribution function (PDF) fit by means of normalized distributions and cross-section ratios between data taken at different c.m. values, R13 /7 and R13 /5. We demonstrate that forward charm production leads to a reduction of the PDF uncertainties of the gluon down to x ≃10-6 by up to an order of magnitude, with implications for high-energy colliders, cosmic ray physics, and neutrino astronomy.

  8. Precision Determination of the Small-x Gluon from Charm Production at LHCb.

    PubMed

    Gauld, Rhorry; Rojo, Juan

    2017-02-17

    The small-x gluon in global fits of parton distributions is affected by large uncertainties from the lack of direct experimental constraints. In this Letter, we provide a precision determination of the small-x gluon from the exploitation of forward charm production data provided by LHCb for three different center-of-mass (c.m.) energies: 5 TeV, 7 TeV, and 13 TeV. The LHCb measurements are included in the parton distribution function (PDF) fit by means of normalized distributions and cross-section ratios between data taken at different c.m. values, R_{13/7} and R_{13/5}. We demonstrate that forward charm production leads to a reduction of the PDF uncertainties of the gluon down to x≃10^{-6} by up to an order of magnitude, with implications for high-energy colliders, cosmic ray physics, and neutrino astronomy.

  9. Asparagine-linked oligosaccharides on lutropin, follitropin, and thyrotropin: distributions of sulfated and sialylated oligosaccharides on bovine, ovine, and human pituitary glycoprotein hormones

    SciTech Connect

    Green, E.D.; Baenziger, J.U.

    1988-01-05

    The asparagine-linked oligosaccharides on the pituitary glycoprotein hormones lutropin (LH), follitropin (FSH), and thyrotropin (TSH) consist of a heterogeneous array of neutral, sulfated, sialylated, and sulfated/sialylated structures. In this study, the authors determined the relative quantities of the various asparagine-linked oligosaccharides on LH, FSH, and TSH from these three animal species. The proportions of sulfated versus sialylated oligosaccharides varied markedly among the different hormones. Both hormone- and animal species-specific differences in the types and distributions of sulfated, sialylated, and sulfated/sialylated structures were evident. In particular, LH and FSH, which are synthesized in the same pituitary cell and bear ..cap alpha..-subunits with the identical amino acid sequence, contained significantly different distributions of sulfated and sialylated oligosaccharides. For all three animal species, the ratio of sialylated to sulfated oligosaccharides differed by >10-fold for LH and FSH, with sulfated structures dominating on LH and sialylated structures on FSH. Sialylated oligosaccharides were also heterogeneous with respect to sialic acid linkage (..cap alpha..2,3 versus ..cap alpha..2,6). The differences in oligosaccharide structures among the various pituitary glycoprotein hormones as well as among the various glycosylation sites within a single hormone support the hypothesis that glycosylation may serve important functional roles in the expression and/or regulation of hormone bioactivity.

  10. Molecular Line Parameters Precisely Determined by a Cavity Ring-Down Spectrometer

    NASA Astrophysics Data System (ADS)

    Hu, Shui-Ming; Tan, Yan; Wang, Jin; Lu, Yan; Cheng, Cunfeng; Sun, Yu Robert; Liu, An-Wen

    2015-06-01

    A cavity ring-down spectrometer calibrated with a set of precise atomic lines was built to retrieve precise line parameters in the near infrared.~[1,2] The spectrometer allows us to detect absorptions with a sensitivity of 10-11~cm-1 and a spectral precision up to 10-6~cm-1. Ro-vibrational lines in the second overtone of H_2 have been observed, including the extremely weak S_3(5) line with a line intensity less than 1× 10-30cm/molecule, which is among the weakest molecular lines detected by absorption in the gas phase. The absolute line positions of H_2 agree well with the high-level quantum chemical calculations including relativistic and QED corrections, with the deviation being less than 5× 10-4~cm-1.~[3,4] A quantitative study has also been carried out on the ν_1+5ν_3 band of CO_2.~[5] It was the first CO_2 band observed 80 years ago in the spectrum of Venus. We determined the line positions with an accuracy of 3× 10-5~cm-1, two orders of magnitude better than previous studies. Similar studies have been carried out to determine the line parameters of H_2O~[6] and CO~[7] in the spectral regions near 0.8~μm. The spectroscopic parameters can be used in varies studies, from the atmospheres of the earth-like planets to the test of fundamental physics. References [1] H. Pan, et al. Rev. Sci. Instrum. 82, 103110 (2011). [2] C.-F. Cheng, Opt. Expr. 20, 9956 (2012). [3] C.-F. Cheng, et al. Phys. Rev. A 85, 024501 (2012). [4] y. Tan, et al. J. Mol. Spectrosc. 300, 60 (2014). [5] Y. Lu, et al. Astrophys. J. 775, 71 (2013). [6] Y. Lu, et al. JQSRT 118, 96 (2013). [7] Y. Tan, et al. ``Ro-vibrational analysis of the fifth overtone of CO at 802~nm'', under preparation.

  11. Aerosol optical depth determination in the UV using a four-channel precision filter radiometer

    NASA Astrophysics Data System (ADS)

    Carlund, Thomas; Kouremeti, Natalia; Kazadzis, Stelios; Gröbner, Julian

    2017-03-01

    The determination of aerosol properties, especially the aerosol optical depth (AOD) in the ultraviolet (UV) wavelength region, is of great importance for understanding the climatological variability of UV radiation. However, operational retrievals of AOD at the biologically most harmful wavelengths in the UVB are currently only made at very few places. This paper reports on the UVPFR (UV precision filter radiometer) sunphotometer, a stable and robust instrument that can be used for AOD retrievals at four UV wavelengths. Instrument characteristics and results of Langley calibrations at a high-altitude site were presented. It was shown that due to the relatively wide spectral response functions of the UVPFR, the calibration constants (V0) derived from Langley plot calibrations underestimate the true extraterrestrial signals. Accordingly, correction factors were introduced. In addition, the instrument's spectral response functions also result in an apparent air-mass-dependent decrease in ozone optical depth used in the AOD determinations. An adjusted formula for the calculation of AOD, with a correction term dependent on total column ozone amount and ozone air mass, was therefore introduced. Langley calibrations performed 13-14 months apart resulted in sensitivity changes of ≤ 1.1 %, indicating good instrument stability. Comparison with a high-accuracy standard precision filter radiometer, measuring AOD at 368-862 nm wavelengths, showed consistent results. Also, very good agreement was achieved by comparing the UVPFR with AOD at UVB wavelengths derived with a Brewer spectrophotometer, which was calibrated against the UVPFR at an earlier date. Mainly due to non-instrumental uncertainties connected with ozone optical depth, the total uncertainty of AOD in the UVB is higher than that reported from AOD instruments measuring in UVA and visible ranges. However, the precision can be high among instruments using harmonized algorithms for ozone and Rayleigh optical depth as

  12. Entry Abort Determination Using Non-Adaptive Neural Networks for Mars Precision Landers

    NASA Technical Reports Server (NTRS)

    Graybeal, Sarah R.; Kranzusch, Kara M.

    2005-01-01

    The 2009 Mars Science Laboratory (MSL) will attempt the first precision landing on Mars using a modified version of the Apollo Earth entry guidance program. The guidance routine, Entry Terminal Point Controller (ETPC), commands the deployment of a supersonic parachute after converging the range to the landing target. For very dispersed cases, ETPC may not converge the range to the target and safely command parachute deployment within Mach number and dynamic pressure constraints. A full-lift up abort can save 85% of these failed trajectories while abandoning the precision landing objective. Though current MSL requirements do not call for an abort capability, an autonomous abort capability may be desired, for this mission or future Mars precision landers, to make the vehicle more robust. The application of artificial neural networks (NNs) as an abort determination technique was evaluated by personnel at the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC). In order to implement an abort, a failed trajectory needs to be recognized in real time. Abort determination is dependent upon several trajectory parameters whose relationships to vehicle survival are not well understood, and yet the lander must be trained to recognize unsafe situations. Artificial neural networks (NNs) provide a way to model these parameters and can provide MSL with the artificial intelligence necessary to independently declare an abort. Using the 2009 Mars Science Laboratory (MSL) mission as a case study, a non-adaptive NN was designed, trained and tested using Monte Carlo simulations of MSL descent and incorporated into ETPC. Neural network theory, the development history of the MSL NN, and initial testing with severe dust storm entry trajectory cases are discussed in Reference 1 and will not be repeated here. That analysis demonstrated that NNs are capable of recognizing failed descent trajectories and can significantly increase the survivability of MSL for very

  13. Precision geoid determination by spherical FFT in and around the Korean peninsula

    NASA Astrophysics Data System (ADS)

    Yun, H.-S.

    1999-01-01

    This paper deals with the precision geoid determination by a gravimetric solution in and around the Korean peninsula. A number of data files were compiled for this work, containing now more than 69,900 point gravity data on land and ocean areas. The EGM96 global geopotential model to degree 360 was used in order to determine the long wavelength effect of the geoid surface. By applying the remove-restore technique the geoid undulations were determined by combining a geopotential model, mean free-air gravity anomalies and height in a Digital Elevation Model (DEM)null. Computation involves a spherical approximation to conduct the Stokes' integration by a two dimensional spherical Fast Fourier Transform (FFT) with 100% zero-padding. A terrain correction was also computed by FFT with a spherical approximation of the Residual Terrain Model (RTM) terrain correction integration. Accuracy estimates are given for absolute geoid undulations using 78 GPS/Leveling stations. The comparative evaluation gives the bias of 0.187 meters and standard deviation of 0.28 meters, respectively. The relative accuracy achieved was of the order of 3.1 ppm for baselines between 10 and 350 kilometers.

  14. Desaturation manoeuvres and precise orbit determination for the BepiColombo mission

    NASA Astrophysics Data System (ADS)

    Alessi, E. M.; Cicalò, S.; Milani, A.; Tommei, G.

    2012-07-01

    This work analyses the consequences that the desaturation manoeuvres can have on the precise orbit determination corresponding to the Mercury Orbiter Radioscience Experiment (MORE) of the BepiColombo mission to Mercury. This is an ESA/JAXAjoint project with challenging objectives regarding geodesy, geophysics and fundamental physics. We will show how these manoeuvres affect the orbit of the s/c and the radio science measurements and how to include them in the orbit determination and parameter estimation procedure. The non-linear least-squares fit is applied on a set of observational arcs separated by intervals of time where the probe is not visible. With the current baseline of two ground stations, two manoeuvres are performed per day, one during the observing session and the other in the dark. To reach the scientific goals of the mission, they have to be treated as 'solve for quantities'. We developed a specific methodology based on the deterministic propagation of the orbit, which is able to deal with these variables, by connecting subsequent observational arcs in a smooth way. The numerical simulations demonstrate that this constrained multi-arc strategy is able to determine all the manoeuvres together with the other parameters of interest at a high level of accuracy.

  15. Chromatographic Separations of Enantiomers and Underivatized Oligosaccharides

    SciTech Connect

    Liu, Ying

    2004-01-01

    My graduate research has focused on separation science and bioanalytical analysis, which emphasized in method development. It includes three major areas: enantiomeric separations using high performance liquid chromatography (HPLC), Super/subcritical fluid chromatography (SFC), and capillary electrophoresis (CE); drug-protein binding behavior studies using CE; and carbohydrate analysis using liquid chromatograph-electrospray ionization mass spectrometry (LC-ESI-MS). Enantiomeric separations continue to be extremely important in the pharmaceutical industry. An in-depth evaluation of the enantiomeric separation capabilities of macrocyclic glycopeptides CSPs with SFC mobile phases was investigated using a set of over 100 chiral compounds. It was found that the macrocyclic based CSPs were able to separate enantiomers of various compounds with different polarities and functionalities. Seventy percent of all separations were achieved in less than 4 min due to the high flow rate (4.0 ml/min) that can be used in SFC. Drug-protein binding is an important process in determining the activity and fate of a drug once it enters the body. Two drug/protein systems have been studied using frontal analysis CE method. More sensitive fluorescence detection was introduced in this assay, which overcame the problem of low sensitivity that is common when using UV detection for drug-protein studies. In addition, the first usage of an argon ion laser with 257 nm beam coupled with CCD camera as a frontal analysis detection method enabled the simultaneous observation of drug fluorescence as well as the protein fluorescence. LC-ESI-MS was used for the separation and characterization of underivatized oligosaccharide mixtures. With the limits of detection as low as 50 picograms, all individual components of oligosaccharide mixtures (up to 11 glucose-units long) were baseline resolved on a Cyclobond I 2000 column and detected using ESI-MS. This system is characterized by high chromatographic

  16. Modeling of Non-Gravitational Forces for Precise and Accurate Orbit Determination

    NASA Astrophysics Data System (ADS)

    Hackel, Stefan; Gisinger, Christoph; Steigenberger, Peter; Balss, Ulrich; Montenbruck, Oliver; Eineder, Michael

    2014-05-01

    Remote sensing satellites support a broad range of scientific and commercial applications. The two radar imaging satellites TerraSAR-X and TanDEM-X provide spaceborne Synthetic Aperture Radar (SAR) and interferometric SAR data with a very high accuracy. The precise reconstruction of the satellite's trajectory is based on the Global Positioning System (GPS) measurements from a geodetic-grade dual-frequency Integrated Geodetic and Occultation Receiver (IGOR) onboard the spacecraft. The increasing demand for precise radar products relies on validation methods, which require precise and accurate orbit products. An analysis of the orbit quality by means of internal and external validation methods on long and short timescales shows systematics, which reflect deficits in the employed force models. Following the proper analysis of this deficits, possible solution strategies are highlighted in the presentation. The employed Reduced Dynamic Orbit Determination (RDOD) approach utilizes models for gravitational and non-gravitational forces. A detailed satellite macro model is introduced to describe the geometry and the optical surface properties of the satellite. Two major non-gravitational forces are the direct and the indirect Solar Radiation Pressure (SRP). The satellite TerraSAR-X flies on a dusk-dawn orbit with an altitude of approximately 510 km above ground. Due to this constellation, the Sun almost constantly illuminates the satellite, which causes strong across-track accelerations on the plane rectangular to the solar rays. The indirect effect of the solar radiation is called Earth Radiation Pressure (ERP). This force depends on the sunlight, which is reflected by the illuminated Earth surface (visible spectra) and the emission of the Earth body in the infrared spectra. Both components of ERP require Earth models to describe the optical properties of the Earth surface. Therefore, the influence of different Earth models on the orbit quality is assessed. The scope of

  17. Precise determination of U isotopic compositions in low concentration carbonate samples by MC-ICP-MS.

    PubMed

    Wang, Ruo-Mei; You, Chen-Feng

    2013-03-30

    We developed a fast and simple analytical procedure for precise determination of U isotopic compositions in low concentration natural samples. The main advantage of the new method is that it requires only 12ng U and can obtain all U isotopic ratios without using spike. Five carbonate reference materials (JCp-1, RKM-4, RKM-5, GBW04412 and GBW04413) and 3 international standards with different matrices (IAPSO, IRMM-3184 and CRM-U010) were analyzed for ((234)U/(238)U) and (238)U/(235)U ratios by MC-ICPMS. Using our method, the results for these standards are in close agreement with the certified values, 1.144 ± 0.004, 0.966 ± 0.004 and 0.990 ± 0.003 for ((234)U/(238)U) and 137.72 ± 0.13, 137.64 ± 0.15 and 98.63 ± 0.04 for (238)U/(235)U, in IAPSO, IRMM-3184 and CRM-U010, respectively. The long-term reproducibility of ((234)U/(238)U) and (238)U/(235)U is 0.970 ± 0.002 and 137.56 ± 0.09; 1.144 ± 0.004 and 137.72 ± 0.13, respectively, for in-house U solution and IAPSO. The new ((234)U/(238)U) results for carbonates show much better precision than previous studies and also reflect their age variability. The obtained (238)U/(235)U ratios, representing the first measurements in these carbonate specimens, are rather constant. The method described here requires only 12 ng of U for analysis and can be completed in 5.2 min. The approach provides a fast method to measure ((234)U/(238)U) and (238)U/(235)U ratios in sample matrices commonly encountered in studies of chemical weathering, oceanography and paleoclimatology.

  18. Impact of Ionosphere on GPS-based Precise Orbit Determination of Low Earth Orbiters

    NASA Astrophysics Data System (ADS)

    Arnold, D.; Jaeggi, A.; Beutler, G.; Meyer, U.; Schaer, S.

    2015-12-01

    Deficiencies in geodetic products derived from the orbital trajectories of Low Earth Orbiting (LEO) satellites determined by GPS-based Precise Orbit Determination (POD) were identified in recent years. The precise orbits of the Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) mission are, e.g., severely affected by an increased position noise level over the geomagnetic poles and spurious signatures along the Earth's geomagnetic equator (see Fig. 1, which shows the carrier phase residuals of a reduced-dynamic orbit determination for GOCE in m). Such degradations may directly map into the gravity fields recovered from the orbits. They are related to a disturbed GPS signal propagation through the Earth's ionosphere and indicate that the GPS observation model and/or the data pre-processing need to be improved. While GOCE was the first mission where severe ionosphere-related problems became obvious, the GPS-based LEO POD of satellites of the more recent missions Swarm and Sentinel-1A turn out to be affected, as well. We characterize the stochastic and systematic behavior of the ionosphere by analyzing GPS data collected by the POD antennas of various LEO satellites covering a broad altitude range (e.g., GRACE, GOCE and Swarm) and for periods covering significant parts of an entire solar cycle, which probe substantially different ionosphere conditions. The information may provide the basis for improvements of data pre-processing to cope with the ionosphere-induced problems of LEO POD. The performance of cycle slip detection can, e.g., be degraded by large changes of ionospheric refraction from one measurement epoch to the next. Geographically resolved information on the stochastic properties of the ionosphere above the LEOs provide more realistic threshold values for cycle slip detection algorithms. Removing GPS data showing large ionospheric variations is a crude method to mitigate the ionosphere-induced artifacts in orbit and gravity field products

  19. Application of Vehicle Dynamic Modeling in Uavs for Precise Determination of Exterior Orientation

    NASA Astrophysics Data System (ADS)

    Khaghani, M.; Skaloud, J.

    2016-06-01

    Advances in unmanned aerial vehicles (UAV) and especially micro aerial vehicle (MAV) technology together with increasing quality and decreasing price of imaging devices have resulted in growing use of MAVs in photogrammetry. The practicality of MAV mapping is seriously enhanced with the ability to determine parameters of exterior orientation (EO) with sufficient accuracy, in both absolute and relative senses (change of attitude between successive images). While differential carrier phase GNSS satisfies cm-level positioning accuracy, precise attitude determination is essential for both direct sensor orientation (DiSO) and integrated sensor orientation (ISO) in corridor mapping or in block configuration imaging over surfaces with low texture. Limited cost, size, and weight of MAVs represent limitations on quality of onboard navigation sensors and puts emphasis on exploiting full capacity of available resources. Typically short flying times (10-30 minutes) also limit the possibility of estimating and/or correcting factors such as sensor misalignment and poor attitude initialization of inertial navigation system (INS). This research aims at increasing the accuracy of attitude determination in both absolute and relative senses with no extra sensors onboard. In comparison to classical INS/GNSS setup, novel approach is presented here to integrated state estimation, in which vehicle dynamic model (VDM) is used as the main process model. Such system benefits from available information from autopilot and physical properties of the platform in enhancing performance of determination of trajectory and parameters of exterior orientation consequently. The navigation system employs a differential carrier phase GNSS receiver and a micro electro-mechanical system (MEMS) grade inertial measurement unit (IMU), together with MAV control input from autopilot. Monte-Carlo simulation has been performed on trajectories for typical corridor mapping and block imaging. Results reveal

  20. Precise timing of the last interglacial period from mass spectrometric determination of thorium-230 in corals.

    PubMed

    Edwards, R L; Chen, J H; Ku, T L; Wasserburg, G J

    1987-06-19

    The development of mass spectrometric techniques for determination of (230)Th abundance has made it possible to reduce analytical errors in (238)U-(234)U-(230)Th dating of corals even with very small samples. Samples of 6 x 10(8) atoms of (230)Th can be measured to an accuracy of +/-3 percent (2sigma) and 3 x 10(10) atoms of (230)Th can be measured to an accuracy of +/-0.2 percent. The time range over which useful age data on corals can be obtained now ranges from about 50 to about 500,000 years. For young corals, this approach may be preferable to (14)C dating. The precision with which the age of a coral can now be determined should make it possible to critically test the Milankovitch hypothesis concerning Pleistocene climate fluctuations. Analyses of a number of corals that grew during the last interglacial period yield ages of 122,000 to 130,000 years. The ages coincide with, or slightly postdate, the summer solar insolation high at 65 degrees N latitude which occurred 128,000 years ago. This supports the idea that changes in Pleistocene climate can be the result of variations in the distribution of solar insolation caused by changes in the geometry of the earth's orbit and rotation axis.

  1. Analysis of Current Position Determination Accuracy in Natural Resources Canada Precise Point Positioning Service

    NASA Astrophysics Data System (ADS)

    Krzan, Grzegorz; Dawidowicz, Karol; Krzysztof, Świaţek

    2013-09-01

    Precise Point Positioning (PPP) is a technique used to determine highprecision position with a single GNSS receiver. Unlike DGPS or RTK, satellite observations conducted by the PPP technique are not differentiated, therefore they require that parameter models should be used in data processing, such as satellite clock and orbit corrections. Apart from explaining the theory of the PPP technique, this paper describes the available web-based online services used in the post-processing of observation results. The results obtained in the post-processing of satellite observations at three points, with different characteristics of environment conditions, using the CSRS-PPP service, will be presented as the results of the experiment. This study examines the effect of the duration of the measurement session on the results and compares the results obtained by working out observations made by the GPS system and the combined observations from GPS and GLONASS. It also presents the analysis of the position determination accuracy using one and two measurement frequencies

  2. Precise Orbit Determination Of Low Earth Satellites At AIUB Using GPS And SLR Data

    NASA Astrophysics Data System (ADS)

    Jaggi, A.; Bock, H.; Thaller, D.; Sosnica, K.; Meyer, U.; Baumann, C.; Dach, R.

    2013-12-01

    An ever increasing number of low Earth orbiting (LEO) satellites is, or will be, equipped with retro-reflectors for Satellite Laser Ranging (SLR) and on-board receivers to collect observations from Global Navigation Satellite Systems (GNSS) such as the Global Positioning System (GPS) and the Russian GLONASS and the European Galileo systems in the future. At the Astronomical Institute of the University of Bern (AIUB) LEO precise orbit determination (POD) using either GPS or SLR data is performed for a wide range of applications for satellites at different altitudes. For this purpose the classical numerical integration techniques, as also used for dynamic orbit determination of satellites at high altitudes, are extended by pseudo-stochastic orbit modeling techniques to efficiently cope with potential force model deficiencies for satellites at low altitudes. Accuracies of better than 2 cm may be achieved by pseudo-stochastic orbit modeling for satellites at very low altitudes such as for the GPS-based POD of the Gravity field and steady-state Ocean Circulation Explorer (GOCE).

  3. Precise timing of the last interglacial period from mass spectrometric determination of thorium-230 in corals

    NASA Technical Reports Server (NTRS)

    Chen, J. H.; Wasserburg, G. J.; Ku, T.-L.; Edwards, R. Lawrence

    1987-01-01

    The development of mass spectrometric techniques for determination of Th-230 abundance has made it possible to reduce analytical errors in (U-238)-(U-234)-(Th-230) dating of corals even with very small samples. Samples of 6 x 10 to the 8th atoms of Th-230 can be measured to an accuracy of + or - 3 percent (2sigma), and 3 x 10 to the 10th atoms of Th-230 can be measured to an accuracy of + or - 0.2 percent. The time range over which useful age data on corals can be obtained now ranges from about 50 to about 500,000 years. For young corals, this approach may be preferable to C-14 dating. The precision with which the age of a coral can now be determined should make it possible to critically test the Milankovitch hypothesis concerning Pleistocene climate fluctuations. Analyses of a number of corals that grew during the last interglacial period yield ages of 122,000 to 130,000 years. The ages coincide with, or slightly post-date, the summer solar insolation high at 65 deg N latitude which occurred 128,000 years ago. This supports the idea that changes in Pleistocene climate can be the result of variations in the distribution of solar insolation caused by changes in the geometry of the earth's orbit and rotation axis.

  4. High Precision, Directly Determined Radii and Effective Temperatures for Giant Stars

    NASA Astrophysics Data System (ADS)

    van Belle, Gerard

    have demonstrated the potential of all aspects of this program, and through the proposed effort will unify the diverse components to study these giants. A homogenous catalog of linear radii and effective temperatures for hundreds of giants will be generated, which in turn will be used to calibrate radius and temperature scales for application to the broad population of giants. Significance. Fundamental temperature and radius scales are used throughout stellar astrophysics, including stellar structure studies, stellar modeling, galactic spectral synthesis, planet detection studies, and star formation theory. We expect to reduce the error in effective temperature calibration by 2-4x, and the error in linear radius by 2-3x or more. A high- precision improvement to these scales will, in turn, broadly advance a wide swath of studies that depend on precisely knowing the radii and temperature of stars. This proposal aims to produce the definitive linear radius and effective temperature scales for giants. A significant improvement in the determinations of the radii and effective temperatures of giant stars across the HR diagram will have far reaching consequences across the broad expanse of astrophysical research. Relevance to NASA. High-precision calibrations of temperature scales are essential to flux calibrations of past and ongoing NASA science satellite observations, such as those from Spitzer and WISE, and a significantly improved linear radius reference markedly improves Kepler discoveries in both the exoplanet and asteroseismology areas. In addition to the high scientific potential of this program, it also provides technical benefits by furthering interferometric techniques that will be critical for future high angular resolution astronomy.

  5. Oligosaccharides: a boon from nature's desk.

    PubMed

    Belorkar, Seema A; Gupta, A K

    2016-12-01

    This article reviews the varied sources of oligosaccharides available in nature as silent health promoting, integral ingredients of plants as well as animal products like honey and milk. The article focuses on exotic and unfamiliar oligosaccharides like Galactooligosaccharides, Lactulose derived Galactooligosaccharides, Xylooligosaccharides, Arabinooligosaccharides and algae derived Marine oligosaccharides along with the most acknowledged prebiotic fructooligosaccharides. The oligosaccharides are named as on the grounds of the monomeric units forming oligomers with functional properties. The chemical structures, natural sources, microbial enzyme mediated synthesis and physiological effects are discussed. An elaborate account of the different types of oligosaccharides with special reference to fructooligosaccharides are presented. Finally, the profound health benefits of oligosaccharides are rigourously discussed limelighting its positive physiological sequel.

  6. Enzymatic synthesis of prebiotic oligosaccharides.

    PubMed

    Rabelo, Maria C; Honorato, Talita L; Gonçalves, Luciana R B; Pinto, Gustavo A S; Rodrigues, Sueli

    2006-04-01

    Prebiotic oligosaccharides are nondigestible carbohydrates that can be obtained by enzymatic synthesis. Glucosyltransferases can be used to produce these carbohydrates through an acceptor reaction synthesis. When maltose is the acceptor a trisaccharide composed of one maltose unit and one glucose unit linked by an alpha-1,6-glycosidic bond (panose) is obtained as the primer product of the dextransucrase acceptor reaction. In this work, panose enzymatic synthesis was evaluated by a central composite experimental design in which maltose and sucrose concentration were varied in a wide range of maltose/sucrose ratios in a batch reactor system. A partially purified enzyme was used in order to reduce the process costs, because enzyme purification is one of the most expensive steps in enzymatic synthesis. Even using high maltose/sucrose ratios, dextran and higher-oligosaccharide formation were not avoided. The results showed that intermediate concentrations of sucrose and high maltose concentration resulted in high panose productivity with low dextran and higher-oligosaccharide productivity.

  7. How Bright is the Proton? A Precise Determination of the Photon Parton Distribution Function

    NASA Astrophysics Data System (ADS)

    Manohar, Aneesh; Nason, Paolo; Salam, Gavin P.; Zanderighi, Giulia

    2016-12-01

    It has become apparent in recent years that it is important, notably for a range of physics studies at the Large Hadron Collider, to have accurate knowledge on the distribution of photons in the proton. We show how the photon parton distribution function (PDF) can be determined in a model-independent manner, using electron-proton (e p ) scattering data, in effect viewing the e p →e +X process as an electron scattering off the photon field of the proton. To this end, we consider an imaginary, beyond the Standard Model process with a flavor changing photon-lepton vertex. We write its cross section in two ways: one in terms of proton structure functions, the other in terms of a photon distribution. Requiring their equivalence yields the photon distribution as an integral over proton structure functions. As a result of the good precision of e p data, we constrain the photon PDF at the level of 1%-2% over a wide range of momentum fractions.

  8. Precise timing of the last interglacial period from mass spectrometric determination of thorium-230 in corals

    SciTech Connect

    Edwards, R.L.; Chen, J.H.; Ku, T.L.; Wasserburg, G.J.

    1987-06-19

    The development of mass spectrometric techniques for determination of STTh abundance has made it possible to reduce analytical errors in STYU-STUU-STTh dating of corals even with very small samples. Samples of 6 x 10Y atoms of STTh can be measured to an accuracy of +/- 3% (2sigma) and 3 x 10 atoms of STTh can be measured to an accuracy of +/- 0.2%. The time range over which useful age data on corals can be obtained now ranges from about 50 to about 500,000 years. For young corals, this approach may be preferable to UC dating. The precision should make it possible to critically test the Milankovitch hypothesis concerning Pleistocene climate fluctuations. Analyses of a number of corals that grew during the last interglacial period yield ages of 122,000 to 130,000 years. The ages coincide with, or slightly postdate, the summer solar insolation high at 65N latitude which occurred 128,000 years ago. This supports the idea that changes in Pleistocene climate can be the result of variations in the distribution of solar insolation caused by changes in the geometry of the earth's orbit and rotation axis.

  9. A Novel Method for Precise Onboard Real-Time Orbit Determination with a Standalone GPS Receiver

    PubMed Central

    Wang, Fuhong; Gong, Xuewen; Sang, Jizhang; Zhang, Xiaohong

    2015-01-01

    Satellite remote sensing systems require accurate, autonomous and real-time orbit determinations (RTOD) for geo-referencing. Onboard Global Positioning System (GPS) has widely been used to undertake such tasks. In this paper, a novel RTOD method achieving decimeter precision using GPS carrier phases, required by China’s HY2A and ZY3 missions, is presented. A key to the algorithm success is the introduction of a new parameter, termed pseudo-ambiguity. This parameter combines the phase ambiguity, the orbit, and clock offset errors of the GPS broadcast ephemeris together to absorb a large part of the combined error. Based on the analysis of the characteristics of the orbit and clock offset errors, the pseudo-ambiguity can be modeled as a random walk, and estimated in an extended Kalman filter. Experiments of processing real data from HY2A and ZY3, simulating onboard operational scenarios of these two missions, are performed using the developed software SATODS. Results have demonstrated that the position and velocity accuracy (3D RMS) of 0.2–0.4 m and 0.2–0.4 mm/s, respectively, are achieved using dual-frequency carrier phases for HY2A, and slightly worse results for ZY3. These results show it is feasible to obtain orbit accuracy at decimeter level of 3–5 dm for position and 0.3–0.5 mm/s for velocity with this RTOD method. PMID:26690149

  10. A Novel Method for Precise Onboard Real-Time Orbit Determination with a Standalone GPS Receiver.

    PubMed

    Wang, Fuhong; Gong, Xuewen; Sang, Jizhang; Zhang, Xiaohong

    2015-12-04

    Satellite remote sensing systems require accurate, autonomous and real-time orbit determinations (RTOD) for geo-referencing. Onboard Global Positioning System (GPS) has widely been used to undertake such tasks. In this paper, a novel RTOD method achieving decimeter precision using GPS carrier phases, required by China's HY2A and ZY3 missions, is presented. A key to the algorithm success is the introduction of a new parameter, termed pseudo-ambiguity. This parameter combines the phase ambiguity, the orbit, and clock offset errors of the GPS broadcast ephemeris together to absorb a large part of the combined error. Based on the analysis of the characteristics of the orbit and clock offset errors, the pseudo-ambiguity can be modeled as a random walk, and estimated in an extended Kalman filter. Experiments of processing real data from HY2A and ZY3, simulating onboard operational scenarios of these two missions, are performed using the developed software SATODS. Results have demonstrated that the position and velocity accuracy (3D RMS) of 0.2-0.4 m and 0.2-0.4 mm/s, respectively, are achieved using dual-frequency carrier phases for HY2A, and slightly worse results for ZY3. These results show it is feasible to obtain orbit accuracy at decimeter level of 3-5 dm for position and 0.3-0.5 mm/s for velocity with this RTOD method.

  11. Factors determining the stability, resolution, and precision of a conventional Raman spectrometer.

    PubMed

    Fukura, Satoshi; Mizukami, Tomoyuki; Odake, Shoko; Kagi, Hiroyuki

    2006-08-01

    We verified the performance of a conventional Raman spectrometer, which is composed of a 30 cm single polychromator, a Si based charge-coupled device (CCD) camera, and a holographic supernotch filter. For that purpose, the time change of the peak positions of Raman spectra of naphthalene and fluorescence spectra of ruby (Cr-doped Al(2)O(3)) were monitored continually. A time-dependent deviation composed of two components was observed: a monotonous drift up to 0.4 cm(-1) and a periodic oscillation with a range of 0.15 cm(-1). The former component was stabilized at approximately 2000 s after the CCD detector was cooled, indicating that incomplete refrigeration of the CCD detector induced the drift. The latter component synchronized with the periodic oscillation of the room temperature, indicating that thermal expansion or contraction of the whole apparatus induced this oscillation. The implemental deviation is reduced when measurements are conducted using a sufficiently cooled CCD detector at a constant room temperature. Moreover, the effect of the room temperature oscillation is lowered in a spectrum acquired over a duration that is longer than one cycle of this oscillation. Applying the least squares fitting method to carefully measured spectra enhanced the precision of the determination of the peak position to 0.05 cm(-1) using the spectrometer with pixel resolution of 1.5 cm(-1).

  12. Transcriptional analysis of oligosaccharide utilization by Bifidobacterium lactis Bl-04

    PubMed Central

    2013-01-01

    Background Probiotic bifidobacteria in combination with prebiotic carbohydrates have documented positive effects on human health regarding gastrointestinal disorders and improved immunity, however the selective routes of uptake remain unknown for most candidate prebiotics. The differential transcriptomes of Bifidobacterium animalis subsp. lactis Bl-04, induced by 11 potential prebiotic oligosaccharides were analyzed to identify the genetic loci involved in the uptake and catabolism of α- and β-linked hexoses, and β-xylosides. Results The overall transcriptome was modulated dependent on the type of glycoside (galactosides, glucosides or xylosides) utilized. Carbohydrate transporters of the major facilitator superfamily (induced by gentiobiose and β-galacto-oligosaccharides (GOS)) and ATP-binding cassette (ABC) transporters (upregulated by cellobiose, GOS, isomaltose, maltotriose, melibiose, panose, raffinose, stachyose, xylobiose and β-xylo-oligosaccharides) were differentially upregulated, together with glycoside hydrolases from families 1, 2, 13, 36, 42, 43 and 77. Sequence analysis of the identified solute-binding proteins that determine the specificity of ABC transporters revealed similarities in the breadth and selectivity of prebiotic utilization by bifidobacteria. Conclusion This study identified the differential gene expression for utilization of potential prebiotics highlighting the extensive capabilities of Bifidobacterium lactis Bl-04 to utilize oligosaccharides. Results provide insights into the ability of this probiotic microbe to utilize indigestible carbohydrates in the human gastrointestinal tract. PMID:23663691

  13. Precision and Accuracy in the Determination of Sulfur Oxides, Fluoride, and Spherical Aluminosilicate Fly Ash Particles in Project MOHAVE.

    PubMed

    Eatough, Norman L; Eatough, Michele; Joseph, Jyothi M; Caka, Fern M; Lewis, Laura; Eatough, Delbert J

    1997-04-01

    The precision and accuracy of the determination of particulate sulfate and fluoride, and gas phase S02 and HF are estimated from the results obtained from collocated replicate samples and from collocated comparison samples for highland low-volume filter pack and annular diffusion denuder samplers. The results of replicate analysis of collocated samples and replicate analyses of a given sample for the determination of spherical aluminosilicate fly ash particles have also been compared. Each of these species is being used in the chemical mass balance source apportionment of sulfur oxides in the Grand Canyon region as part of Project MOHAVE, and the precision and accuracy analyses given in this paper provide input to that analysis. The precision of the various measurements reported here is ±1.8 nmol/m(3) and ±2.5 nmol/m(3) for the determination of S02 and sulfate, respectively, with an annular denuder. The precision is ±0.5 nmol/m(3) and ±2.0 nmol/m(3) for the determination of the same species with a high-volume or low-volume filter pack. The precision for the determination of the sum of HF(g) and fine particulate fluoride is +0.3 nmol/m(3). The precision for the determination of aluminosilicate fly ash particles is ±100 particles/m(3). At high concentrations of the various species, reproducibility of the various measurements is ±10% to ±14% of the measured concentration. The concentrations of sulfate determined using filter pack samplers are frequently higher than those determined using diffusion denuder sampling systems. The magnitude of the difference (e.g., 2-10 nmol sulfate/m(3)) is small, but important relative to the precision of the data and the concentrations of particulate sulfate present (typically 5-20 nmol sulfate/m(3)). The concentrations of S02(g) determined using a high-volume cascade impactor filter pack sampler are correspondingly lower than those obtained with diffusion denuder samplers. The concentrations of SOx (SOz(g) plus particulate

  14. A Rapid, Convenient, and Precise Method for the Absolute Determination of the Acceleration of Gravity.

    ERIC Educational Resources Information Center

    Manche, Emanuel P.

    1979-01-01

    Describes a compact and portable apparatus for the measurement, with a high degree of precision, the value of the gravitational acceleration g. The apparatus consists of a falling mercury drop and an electronic timing circuit. (GA)

  15. Determination of the Thermal Offset of the Eppley Precision Spectral Pyranometer

    NASA Technical Reports Server (NTRS)

    Haeffelin, Martial; Kato, Seiji; Smith, Amie M.; Rutledge, C. Ken; Charlock, Thomas P.; Mahan, J. Robert

    2001-01-01

    Eppley's precision spectral pyranometer (PSP) is used in networks around the world to measure downwelling diffuse and global solar irradiance at the surface of the Earth. In recent years several studies have shown significant discrepancy between irradiances measured by pyranometers and those computed by atmospheric radiative transfer models. Pyranometer measurements have been questioned because observed diffuse irradiances sometimes are below theoretical minimum values for a pure molecular atmosphere, and at night the instruments often produce nonzero signals ranging between + 5 and - 10 W/sq m. We install thermistor sondes in the body of a PSP as well as on its inner dome to monitor the temperature gradients within the instrument, and we operate a pyrgeometer (PIR) instrument side by side with the PSP. We derive a relationship between the PSP output and thermal radiative exchange by the dome and the detector and a relationship between the PSP output and the PIR thermopile output (net-IR). We determine the true PSP offset by quickly capping the instrument at set time intervals. For a ventilated and shaded PSP, the thermal offset can reach - 15 W/sq m under clear skies, whereas it remains close to zero for low overcast clouds. We estimate the PSP thermal offset by two methods: (1) using the PSP temperatures and (2) using the PIR net-IR signal. The offset computed from the PSP temperatures yields a reliable estimate of the true offset (+/- 1 W/sq m). The offset computed from net-IR is consistent with the true offset at night and under overcast skies but predicts only part of the true range under clear skies.

  16. Analysis of Prebiotic Oligosaccharides

    NASA Astrophysics Data System (ADS)

    Sanz, M. L.; Ruiz-Matute, A. I.; Corzo, N.; Martínez-Castro, I.

    Carbohydrates and more specifically prebiotics, are complex mixtures of isomers with different degrees of polymerization (DP), monosaccharide units and/or glycosidic linkages. Many efforts are focused on the search for new products and the determination of their biological activity. However, the study of their chemical structure is fundamental to both acquire a basic knowledge of the carbohydrate and to increase the understanding of the mechanisms for their metabolic effect.

  17. Model improvements and validation of TerraSAR-X precise orbit determination

    NASA Astrophysics Data System (ADS)

    Hackel, S.; Montenbruck, O.; Steigenberger, P.; Balss, U.; Gisinger, C.; Eineder, M.

    2016-12-01

    The radar imaging satellite mission TerraSAR-X requires precisely determined satellite orbits for validating geodetic remote sensing techniques. Since the achieved quality of the operationally derived, reduced-dynamic (RD) orbit solutions limits the capabilities of the synthetic aperture radar (SAR) validation, an effort is made to improve the estimated orbit solutions. This paper discusses the benefits of refined dynamical models on orbit accuracy as well as estimated empirical accelerations and compares different dynamic models in a RD orbit determination. Modeling aspects discussed in the paper include the use of a macro-model for drag and radiation pressure computation, the use of high-quality atmospheric density and wind models as well as the benefit of high-fidelity gravity and ocean tide models. The Sun-synchronous dusk-dawn orbit geometry of TerraSAR-X results in a particular high correlation of solar radiation pressure modeling and estimated normal-direction positions. Furthermore, this mission offers a unique suite of independent sensors for orbit validation. Several parameters serve as quality indicators for the estimated satellite orbit solutions. These include the magnitude of the estimated empirical accelerations, satellite laser ranging (SLR) residuals, and SLR-based orbit corrections. Moreover, the radargrammetric distance measurements of the SAR instrument are selected for assessing the quality of the orbit solutions and compared to the SLR analysis. The use of high-fidelity satellite dynamics models in the RD approach is shown to clearly improve the orbit quality compared to simplified models and loosely constrained empirical accelerations. The estimated empirical accelerations are substantially reduced by 30% in tangential direction when working with the refined dynamical models. Likewise the SLR residuals are reduced from -3 ± 17 to 2 ± 13 mm, and the SLR-derived normal-direction position corrections are reduced from 15 to 6 mm, obtained from

  18. The Human Milk Metabolome Reveals Diverse Oligosaccharide Profiles123

    PubMed Central

    Smilowitz, Jennifer T.; O’Sullivan, Aifric; Barile, Daniela; German, J. Bruce; Lönnerdal, Bo; Slupsky, Carolyn M.

    2013-01-01

    Breast milk delivers nutrition and protection to the developing infant. There has been considerable research on the high-molecular-weight milk components; however, low-molecular-weight metabolites have received less attention. To determine the effect of maternal phenotype and diet on the human milk metabolome, milk collected at day 90 postpartum from 52 healthy women was analyzed by using proton nuclear magnetic resonance spectroscopy. Sixty-five milk metabolites were quantified (mono-, di-, and oligosaccharides; amino acids and derivatives; energy metabolites; fatty acids and associated metabolites; vitamins, nucleotides, and derivatives; and others). The biological variation, represented as the percentage CV of each metabolite, varied widely (4–120%), with several metabolites having low variation (<20%), including lactose, urea, glutamate, myo-inositol, and creatinine. Principal components analysis identified 2 clear groups of participants who were differentiable on the basis of milk oligosaccharide concentration and who were classified as secretors or nonsecretors of fucosyltransferase 2 (FUT2) gene products according to the concentration of 2′-fucosyllactose, lactodifucotetraose, and lacto-N-fucopentaose I. Exploration of the interrelations between the milk sugars by using Spearman rank correlations revealed significant positive and negative associations, including positive correlations between fucose and products of the FUT2 gene and negative correlations between fucose and products of the fucosyltransferase 3 (FUT3) gene. The total concentration of milk oligosaccharides was conserved among participants (%CV = 18%), suggesting tight regulation of total oligosaccharide production; however, concentrations of specific oligosaccharides varied widely between participants (%CV = 30.4–84.3%). The variability in certain milk metabolites suggests possible roles in infant or infant gut microbial development. This trial was registered at clinicaltrials.gov as NCT

  19. The human milk metabolome reveals diverse oligosaccharide profiles.

    PubMed

    Smilowitz, Jennifer T; O'Sullivan, Aifric; Barile, Daniela; German, J Bruce; Lönnerdal, Bo; Slupsky, Carolyn M

    2013-11-01

    Breast milk delivers nutrition and protection to the developing infant. There has been considerable research on the high-molecular-weight milk components; however, low-molecular-weight metabolites have received less attention. To determine the effect of maternal phenotype and diet on the human milk metabolome, milk collected at day 90 postpartum from 52 healthy women was analyzed by using proton nuclear magnetic resonance spectroscopy. Sixty-five milk metabolites were quantified (mono-, di-, and oligosaccharides; amino acids and derivatives; energy metabolites; fatty acids and associated metabolites; vitamins, nucleotides, and derivatives; and others). The biological variation, represented as the percentage CV of each metabolite, varied widely (4-120%), with several metabolites having low variation (<20%), including lactose, urea, glutamate, myo-inositol, and creatinine. Principal components analysis identified 2 clear groups of participants who were differentiable on the basis of milk oligosaccharide concentration and who were classified as secretors or nonsecretors of fucosyltransferase 2 (FUT2) gene products according to the concentration of 2'-fucosyllactose, lactodifucotetraose, and lacto-N-fucopentaose I. Exploration of the interrelations between the milk sugars by using Spearman rank correlations revealed significant positive and negative associations, including positive correlations between fucose and products of the FUT2 gene and negative correlations between fucose and products of the fucosyltransferase 3 (FUT3) gene. The total concentration of milk oligosaccharides was conserved among participants (%CV = 18%), suggesting tight regulation of total oligosaccharide production; however, concentrations of specific oligosaccharides varied widely between participants (%CV = 30.4-84.3%). The variability in certain milk metabolites suggests possible roles in infant or infant gut microbial development. This trial was registered at clinicaltrials.gov as NCT01817127.

  20. Human milk and related oligosaccharides as prebiotics.

    PubMed

    Barile, Daniela; Rastall, Robert A

    2013-04-01

    Human milk oligosaccharides (HMO) are believed to have a range of biological activities beyond providing nutrition to the infant. Principal among these is that they may act as prebiotics. Prebiotics are dietary ingredients, usually oligosaccharides that provide a health benefit to the host mediated by the modulation of the human gut microbiota. While it is clear that such oligosaccharides may have potential applications in infants and adults alike, this potential is limited by the difficulties in manufacturing HMO. Consequently functional alternatives such as galacto-oligosaccharides (GOS) are under investigation. GOS are produced enzymatically from lactose for commercial use in food applications--including addition to infant formulae--as similar to breast milk oligosaccharides, they encourage a gut bacteria population that promotes health and reduces the incidence of intestinal infections. New methods for separation and concentration of complex, breast milk-like oligosaccharides from bovine milk industrial streams that contain only low amounts of these valuable oligosaccharides are providing the opportunity to investigate other viable sources of specific oligosaccharides for use as prebiotics in supplements or food products.

  1. Important factors determining the nanoscale tracking precision of dynamic microtubule ends

    PubMed Central

    BOHNER, G.; GUSTAFSSON, N.; CADE, N.I.; MAURER, S.P.; GRIFFIN, L.D.

    2016-01-01

    Summary Tracking dynamic microtubule ends in fluorescence microscopy movies provides insight into the statistical properties of microtubule dynamics and is vital for further analysis that requires knowledge of the trajectories of the microtubule ends. Here we analyse the performance of a previously developed automated microtubule end tracking routine; this has been optimized for comparatively low signal‐to‐noise image sequences that are characteristic of microscopy movies of dynamic microtubules growing in vitro. Sequences of simulated microtubule images were generated assuming a variety of different experimental conditions. The simulated movies were then tracked and the tracking errors were characterized. We found that the growth characteristics of the microtubules within realistic ranges had a negligible effect on the tracking precision. The fluorophore labelling density, the pixel size of the images, and the exposure times were found to be important parameters limiting the tracking precision which could be explained using concepts of single molecule localization microscopy. The signal‐to‐noise ratio was found to be a good single predictor of the tracking precision: typical experimental signal‐to‐noise ratios lead to tracking precisions in the range of tens of nanometres, making the tracking program described here a useful tool for dynamic microtubule end tracking with close to molecular precision. PMID:26444439

  2. Towards the GEOSAT Follow-On Precise Orbit Determination Goals of High Accuracy and Near-Real-Time Processing

    NASA Technical Reports Server (NTRS)

    Lemoine, Frank G.; Zelensky, Nikita P.; Chinn, Douglas S.; Beckley, Brian D.; Lillibridge, John L.

    2006-01-01

    The US Navy's GEOSAT Follow-On spacecraft (GFO) primary mission objective is to map the oceans using a radar altimeter. Satellite laser ranging data, especially in combination with altimeter crossover data, offer the only means of determining high-quality precise orbits. Two tuned gravity models, PGS7727 and PGS7777b, were created at NASA GSFC for GFO that reduce the predicted radial orbit through degree 70 to 13.7 and 10.0 mm. A macromodel was developed to model the nonconservative forces and the SLR spacecraft measurement offset was adjusted to remove a mean bias. Using these improved models, satellite-ranging data, altimeter crossover data, and Doppler data are used to compute both daily medium precision orbits with a latency of less than 24 hours. Final precise orbits are also computed using these tracking data and exported with a latency of three to four weeks to NOAA for use on the GFO Geophysical Data Records (GDR s). The estimated orbit precision of the daily orbits is between 10 and 20 cm, whereas the precise orbits have a precision of 5 cm.

  3. A Precise, Simple, and Low-Cost Experiment to Determine the Isobaric Expansion Coefficient for Physical Chemistry Students

    ERIC Educational Resources Information Center

    Pe´rez, Eduardo

    2015-01-01

    The procedure of a physical chemistry experiment for university students must be designed in a way that the accuracy and precision of the measurements is properly maintained. However, in many cases, that requires costly and sophisticated equipment not readily available in developing countries. A simple, low-cost experiment to determine isobaric…

  4. Hydrophilic interaction liquid chromatography for the separation, purification, and quantification of raffinose family oligosaccharides from Lycopus lucidus Turcz.

    PubMed

    Liang, Tu; Fu, Qing; Li, Fangbing; Zhou, Wei; Xin, Huaxia; Wang, Hui; Jin, Yu; Liang, Xinmiao

    2015-08-01

    A systematic strategy based on hydrophilic interaction liquid chromatography was developed for the separation, purification and quantification of raffinose family oligosaccharides from Lycopus lucidus Turcz. Methods with enough hydrophilicity and selectivity were utilized to resolve the problems encountered in the separation of oligosaccharides such as low retention, low resolution and poor solubility. The raffinose family oligosaccharides in L. lucidus Turcz. were isolated using solid-phase extraction followed by hydrophilic interaction liquid chromatography at semi-preparative scale to obtain standards of stachyose, verbascose and ajugose. Utilizing the obtained oligosaccharides as standards, a quantitative determination method was developed, validated and applied for the content determination of raffinose family oligosaccharides both in the aerial and root parts of L. lucidus Turcz. There were no oligosaccharides in the aerial parts, while in the root parts, the total content was 686.5 mg/g with the average distribution: raffinose 66.5 mg/g, stachyose 289.0 mg/g, verbascose 212.4 mg/g, and ajugose 118.6 mg/g. The result provided the potential of roots of L. lucidus Turcz. as new raffinose family oligosaccharides sources for functional food. Moreover, since the present systematic strategy is efficient, sensitive and robust, separation, purification and quantification of oligosaccharides by hydrophilic interaction liquid chromatography seems to be possible.

  5. Precise orbit determination for quad-constellation satellites at Wuhan University: strategy, result validation, and comparison

    NASA Astrophysics Data System (ADS)

    Guo, Jing; Xu, Xiaolong; Zhao, Qile; Liu, Jingnan

    2016-02-01

    This contribution summarizes the strategy used by Wuhan University (WHU) to determine precise orbit and clock products for Multi-GNSS Experiment (MGEX) of the International GNSS Service (IGS). In particular, the satellite attitude, phase center corrections, solar radiation pressure model developed and used for BDS satellites are addressed. In addition, this contribution analyzes the orbit and clock quality of the quad-constellation products from MGEX Analysis Centers (ACs) for a common time period of 1 year (2014). With IGS final GPS and GLONASS products as the reference, Multi-GNSS products of WHU (indicated by WUM) show the best agreement among these products from all MGEX ACs in both accuracy and stability. 3D Day Boundary Discontinuities (DBDs) range from 8 to 27 cm for Galileo-IOV satellites among all ACs' products, whereas WUM ones are the largest (about 26.2 cm). Among three types of BDS satellites, MEOs show the smallest DBDs from 10 to 27 cm, whereas the DBDs for all ACs products are at decimeter to meter level for GEOs and one to three decimeter for IGSOs, respectively. As to the satellite laser ranging (SLR) validation for Galileo-IOV satellites, the accuracy evaluated by SLR residuals is at the one decimeter level with the well-known systematic bias of about -5 cm for all ACs. For BDS satellites, the accuracy could reach decimeter level, one decimeter level, and centimeter level for GEOs, IGSOs, and MEOs, respectively. However, there is a noticeable bias in GEO SLR residuals. In addition, systematic errors dependent on orbit angle related to mismodeled solar radiation pressure (SRP) are present for BDS GEOs and IGSOs. The results of Multi-GNSS combined kinematic PPP demonstrate that the best accuracy of position and fastest convergence speed have been achieved using WUM products, particularly in the Up direction. Furthermore, the accuracy of static BDS only PPP degrades when the BDS IGSO and MEO satellites switches to orbit-normal orientation

  6. Mitotic Index Determined by Phosphohistone H3 Immunohistochemistry for Precise Grading in Follicular Lymphoma.

    PubMed

    Bedekovics, Judit; Irsai, Gábor; Hegyi, Katalin; Beke, Lívia; Krenács, László; Gergely, Lajos; Méhes, Gábor

    2016-12-16

    The World Health Organization classification recommends follicular lymphoma (FL) grading (G1-3) by considering centroblast number, while also suggesting its influence on disease outcome. As centroblast counting and other proliferation markers have limitations, we looked for more specific measures of cellular activity in FL. Phosphorylated histone H3 (pHH3) was widely applied for the objective detection of mitotic activity in different tumors. The aim was to evaluate the utility of pHH3 protein in FL grading and compare its value with the classical features of cell proliferation. Representative samples from 48 FL patients and 9 samples with follicular hyperplasia were examined. Hematoxylin-eosin-based mitosis index (HE-MI), number of mitotic figures based on anti-pHH3 immunohistochemical staining (pHH3-MI), and percentage of Ki-67-positive cells [proliferation index (PI)] were determined and compared with centroblast-based histologic grade. PHH3-MI showed significant correlation with HE-MI (r=0.85, P<0.0001) and PI (r=0.84, P<0.0001). All 3 cell proliferation parameters showed significant correlation with histologic grade: HE-MI versus grade, r=0.85 (P<0.0001); PI versus grade, r=0.74 (P<0.0001); pHH3-MI versus grade, r=0.80 (P<0.0001). PHH3-MI showed continuous increase with the histologic grade. The pHH3-MI value was distinctive between the G2 and the G1 FL groups (P<0.0001) and was increased in G3 FL compared with that in the G2 FL group (P=0.0020). In conclusion, easy-to-perform mitotic counting following phosphohistone H3 immunohistochemistry (pHH3-MI) correlates well with centroblast-based grading. PHH3 immunohistochemistry offers a reliable quantification tool supporting lymphoma grading and can be recommended as an additional parameter for the precise subcategorization of FL cases.

  7. Precise /sup 3/H-/sup 3/He mass difference for neutrino mass determination

    SciTech Connect

    Lippmaa, E.; Pikver, R.; Suurmaa, E.; Past, J.; Puskar, J.; Koppel, I.; Tammik, A.

    1985-01-28

    The precise /sup 3/H-/sup 3/He atomic mass difference has been measured by high-resolution (10/sup -8/) ion cyclotron resonance in a 4.7-T magnetic field. The result of 18 599 +- 2 eV favors a nonzero electron antineutrino mass.

  8. Elucidation of the structure of the oligosaccharide from wild type Moraxella bovis Epp63 lipooligosaccharide.

    PubMed

    De Castro, Cristina; Grice, I Darren; Daal, Terese-Marie; Peak, Ian R; Molinaro, Antonio; Wilson, Jennifer C

    2014-03-31

    Moraxella bovis is a Gram-negative microorganism that causes Infectious Bovine Keratoconjunctivitis (IBK), colloquially known as 'Pink eye' in cattle worldwide. Lipopolysaccharides/lipooligosaccharides are the predominant glycans on the surface of Gram-negative microorganisms. Structural elucidation of the oligosaccharide structure of the rough phenotype of Moraxella bovis strain Epp63 was determined using GC-MS, methylation analysis, and NMR spectroscopy. The oligosaccharide is a branched structure that comprises 10 sugars in addition to KDO. The unusual features of this oligosaccharide include the fact that the oligosaccharide is devoid of heptose. The KDO residue is directly attached to a (→4,6)-branched glucose and additionally contains a terminal open chain acetal-linked N-acetylgalactosamine, (1S)-GalaNAc residue →4,6-linked to a sub-terminal galactose residue.

  9. [Effect of ligand concentration on the precision of determining the parameters of ligand-receptor interaction by serial dilution methods].

    PubMed

    Bobrovnik, S A

    2004-01-01

    Earlier we suggested the method of serial dilution, which allows one to determine the parameters of ligand-receptor interaction even if the reactants are in a mixture and their concentrations are unknown. The method is especially useful if the liability of studied receptor does not allow its separation from corresponding ligand. The important prerequisite of the method's precision is that the concentration of the ligand should be sufficiently high comparing to the concentration of the receptor. In the present paper it was demonstrated that the method allows one to obtain sufficiently good precision even in the case when the concentration of the ligand is only one tenth of the receptor concentration.

  10. Preparation of κ-carra-oligosaccharides with microwave assisted acid hydrolysis method

    NASA Astrophysics Data System (ADS)

    Li, Guangsheng; Zhao, Xia; Lv, Youjing; Li, Miaomiao; Yu, Guangli

    2015-04-01

    A rapid method of microwave assisted acid hydrolysis was established to prepare κ-carra-oligosaccharides. The optimal hydrolysis condition was determined by an orthogonal test. The degree of polymerization (DP) of oligosaccharides was detected by high performance thin layer chromatography (HPTLC) and polyacrylamide gel electrophoresis (PAGE). Considering the results of HPTLC and PAGE, the optimum condition of microwave assisted acid hydrolysis was determined. The concentration of κ-carrageenan was 5 mg mL-1; the reaction solution was adjusted to pH 3 with diluted hydrochloric acid; the solution was hydrolyzed under microwave irradiation at 100 for 15 °C min. Oligosaccharides were separated by a Superdex 30 column (2.6 cm × 90 cm) using AKTA Purifier UPC100 and detected with an online refractive index detector. Each fraction was characterized by electrospray ionization mass spectrometry (ESI-MS). The data showed that odd-numbered κ-carra-oligosaccharides with DP ranging from 3 to 21 could be obtained with this method, and the structures of the oligosaccharides were consistent with those obtained by traditional mild acid hydrolysis. The new method was more convenient, efficient and environment-friendly than traditional mild acid hydrolysis. Our results provided a useful reference for the preparation of oligosaccharides from other polysaccharides.

  11. Precise determination of atomic g-factor ratios from a dual isotope magneto-optical trap

    SciTech Connect

    Chan, I.; Barrett, B.; Kumarakrishnan, A.

    2011-09-15

    We demonstrate a technique, for carrying out precise measurements of atomic g-factor ratios, which relies on measurements of Larmor oscillations from coherences between magnetic sublevels in the ground states of {sup 85}Rb and {sup 87}Rb atoms confined in a dual isotope magneto-optical trap. We show that a measurement of g{sub F}{sup (87)}/g{sub F}{sup (85)} with a resolution of 0.69 parts per 10{sup 6} is possible by recording the ratio of Larmor frequencies in the presence of a constant magnetic field. This represents the most precise single measurement of g{sub F}{sup (87)}/g{sub F}{sup (85)} without correcting for systematic effects.

  12. Piping inspection instrument carriage with precise and repeatable position control and location determination

    DOEpatents

    Hapstack, Mark; Talarek, Ted R.; Zollinger, W. Thor; Heckendorn, II, Frank M.; Park, Larry R.

    1994-01-01

    An instrument carriage for inspection of piping comprises front and rear leg assemblies for engaging the interior of the piping and supporting and centering the carriage therein, and an instrumentation arm carried by a shaft system running from the front to rear leg assemblies. The shaft system has a screw shaft for moving the arm axially and a spline gear for moving the arm azimuthally. The arm has a pair of air cylinders that raise and lower a plate in the radial direction. On the plate are probes including an eddy current probe and an ultrasonic testing probe. The ultrasonic testing probe is capable of spinning 360.degree. about its axis. The instrument carriage uses servo motors and pressurized air cylinders for precise actuation of instrument components and precise, repeatable actuation of position control mechanisms.

  13. Piping inspection instrument carriage with precise and repeatable position control and location determination

    DOEpatents

    Hapstack, M.; Talarek, T.R.; Zollinger, W.T.; Heckendorn, F.M. II; Park, L.R.

    1994-02-15

    An instrument carriage for inspection of piping comprises front and rear leg assemblies for engaging the interior of the piping and supporting and centering the carriage therein, and an instrumentation arm carried by a shaft system running from the front to rear leg assemblies. The shaft system has a screw shaft for moving the arm axially and a spline gear for moving the arm azimuthally. The arm has a pair of air cylinders that raise and lower a plate in the radial direction. On the plate are probes including an eddy current probe and an ultrasonic testing probe. The ultrasonic testing probe is capable of spinning 360[degree] about its axis. The instrument carriage uses servo motors and pressurized air cylinders for precise actuation of instrument components and precise, repeatable actuation of position control mechanisms. 8 figures.

  14. Precise Orbit Determination of Meteors by HPLA Radar and the MU Radar Meteor Head Echo Database

    NASA Astrophysics Data System (ADS)

    Nakamura, Takuji; Yamamoto, Mamoru; Tanaka, Yoshi; Kero, Johan; Szasz, Csilla; Watanabe, Juniichi; Abe, Shinsuke; Kastinen, Daniel

    Mass influx from the space into the terrestrial atmosphere is mainly caused by meteors. Meteors delivers various elements into the atmosphere, but the meteoric dust particles are also of great importance in the terrestrial atmosphere, as they act as nucleus for condensation and clouds and affect various atmospheric phenomena both in physical and chemical aspects. Thus, to investigate the meteor flux, orbits and their interactions in the upper atmosphere is very important but at the same time the method of investigation is limited, especially for the precise measurements High power large aperture (HPLA) radar observation is a recent technique to provide useful information on meteor influx and orbits, as well as interactions with the atmosphere. The recent development of the technique carried out using the middle and upper atmosphere radar (MU radar) of Kyoto University at Shigaraki (34.9N, 136.1S), which is a large atmospheric VHF radar with 46.5 MHz frequency, 1 MW output transmission power and 8330 m2 aperture array antenna, has established very precise orbit observations from meteor head echoes. Since 2009, orbital data of about 120,000 meteors have been collected. An open database (MU radar meteor head echo database: MURMHED) for research and education is now being created. In this study, we present the physical quantities and precisions obtained from the MU radar meteor head echo observations and the details of the open database.

  15. External validation, repeat determination, and precision of risk estimation in misclassified exposure data in epidemiology.

    PubMed Central

    Duffy, S W; Maximovitch, D M; Day, N E

    1992-01-01

    STUDY OBJECTIVE--The aim was to quantify the difference in precision of risk estimates in epidemiology between the situations where misclassification of exposure is corrected for by external validation and where it is corrected for by internal repeat measurement. Precision was measured in terms of the expected width of the 95% confidence interval on the odds ratio. DESIGN--In a hypothetical case-control study, first with 100 cases and 100 controls, then with 100 cases and 1000 controls (the latter to approximate the cohort study situation), expected estimated odds ratios and confidence intervals were calculated based on postulated underlying true odds ratios and misclassification error rates. The sizes of the confidence intervals using the two design strategies were compared, based on the same number of subjects receiving internal repeat measurements as were used in the external validation study. MAIN RESULTS--Confidence intervals obtained using internal repeat measurement were considerably narrower than those using external validation. Both methods yielded approximately correct point estimates. CONCLUSIONS--In terms of precision, it is preferable to correct for misclassification using internal repeat measurement rather than external validation. PMID:1494080

  16. Nature and biosynthesis of galacto-oligosaccharides related to oligosaccharides in human breast milk

    PubMed Central

    Intanon, Montira; Arreola, Sheryl Lozel; Pham, Ngoc Hung; Kneifel, Wolfgang; Haltrich, Dietmar; Nguyen, Thu-Ha

    2014-01-01

    Human milk oligosaccharides (HMO) are prominent among the functional components of human breast milk. While HMO have potential applications in both infants and adults, this potential is limited by the difficulties in manufacturing these complex structures. Consequently, functional alternatives such as galacto-oligosaccharides are under investigation, and nowadays, infant formulae are supplemented with galacto-oligosaccharides to mimic the biological effects of HMO. Recently, approaches toward the production of defined human milk oligosaccharide structures using microbial, fermentative methods employing single, appropriately engineered microorganisms were introduced. Furthermore, galactose-containing hetero-oligosaccharides have attracted an increasing amount of attention because they are structurally more closely related to HMO. The synthesis of these novel oligosaccharides, which resemble the core of HMO, is of great interest for applications in the food industry. PMID:24571717

  17. Advances in Analysis of Human Milk Oligosaccharides123

    PubMed Central

    Ruhaak, L. Renee; Lebrilla, Carlito B.

    2012-01-01

    Oligosaccharides in human milk strongly influence the composition of the gut microflora of neonates. Because it is now clear that the microflora play important roles in the development of the infant immune system, human milk oligosaccharides (HMO) are studied frequently. Milk samples contain complex mixtures of HMO, usually comprising several isomeric structures that can be either linear or branched. Traditionally, HMO profiling was performed using HPLC with fluorescence or UV detection. By using porous graphitic carbon liquid chromatography MS, it is now possible to separate and identify most of the isomers, facilitating linkage-specific analysis. Matrix-assisted laser desorption ionization time-of-flight analysis allows fast profiling, but does not allow isomer separation. Novel MS fragmentation techniques have facilitated structural characterization of HMO that are present at lower concentrations. These techniques now facilitate more accurate studies of HMO consumption as well as Lewis blood group determinations. PMID:22585919

  18. An evaluation of the precision of fin ray, otolith, and scale age determinations for brook trout

    USGS Publications Warehouse

    Stolarski, J.T.; Hartman, K.J.

    2008-01-01

    The ages of brook trout Salvelinus fontinalis are typically estimated using scales despite a lack of research documenting the effectiveness of this technique. The use of scales is often preferred because it is nonlethal and is believed to require less effort than alternative methods. To evaluate the relative effectiveness of different age estimation methodologies for brook trout, we measured the precision and processing times of scale, sagittal otolith, and pectoral fin ray age estimation techniques. Three independent readers, age bias plots, coefficients of variation (CV = 100 x SD/mean), and percent agreement (PA) were used to measure within-reader, among-structure bias and within-structure, among-reader precision. Bias was generally minimal; however, the age estimates derived from scales tended to be lower than those derived from otoliths within older (age > 2) cohorts. Otolith, fin ray, and scale age estimates were within 1 year of each other for 95% of the comparisons. The measures of precision for scales (CV = 6.59; PA = 82.30) and otoliths (CV = 7.45; PA = 81.48) suggest higher agreement between these structures than with fin rays (CV = 11.30; PA = 65.84). The mean per-sample processing times were lower for scale (13.88 min) and otolith techniques (12.23 min) than for fin ray techniques (22.68 min). The comparable processing times of scales and otoliths contradict popular belief and are probably a result of the high proportion of regenerated scales within samples and the ability to infer age from whole (as opposed to sectioned) otoliths. This research suggests that while scales produce age estimates rivaling those of otoliths for younger (age > 3) cohorts, they may be biased within older cohorts and therefore should be used with caution. ?? Copyright by the American Fisheries Society 2008.

  19. Precise Determination of the Neutron Magnetic Form Factor to Higher Q{sup 2}

    SciTech Connect

    William K. Brooks; Jeffery D. Lachniet

    2004-10-01

    The neutron elastic magnetic form factor G{sub M}{sup n} has been extracted from quasielastic scattering from deuterium in the CEBAF Large Acceptance Spectrometer, CLAS. The kinematic coverage of the measurement is continuous over a broad range, extending from below 1 GeV{sup 2} to nearly 5 GeV{sup 2} in four-momentum transfer squared. High precision is achieved by employing a ratio technique in which most uncertainties cancel, and by a simultaneous in-situ calibration of the neutron detection efficiency, the largest correction to the data. Preliminary results are shown with statistical errors only.

  20. In vitro fermentation of prebiotic oligosaccharides by Bifidobacterium lactis HN019 and Lactobacillus spp.

    PubMed

    Sims, Ian M; Ryan, Jason L J; Kim, Sang H

    2014-02-01

    The utilisation of various prebiotic oligosaccharides by probiotic strains of Bifidobacterium lactis, Lactobacillus rhamnosus and Lactobacillus acidophilus was investigated in order to determine the synbiotic potential of various prebiotic/probiotic combinations. Analysis by HPLC and high-performance anion-exchange chromatography of the cell-free medium taken during growth of the three probiotic bacteria showed differences in the consumption of the various oligosaccharides. Analysis of galactooligosaccharides showed that both L. rhamnosus and B. lactis consumed mostly mono- and di-saccharide, while L. acidophilus consumed oligosaccharides up to trisaccharide. Both B. lactis and L. acidophilus utilised fructooligosaccharides and inulin, but showed different patterns of oligosaccharide consumption. Only L. rhamnosus grew on β-glucan oligosaccharides and preferentially consumed the trisaccharide. The results indicate the synbiotic potential of the various probiotic/prebiotic combinations, particularly L. acidophilus/galactooligosaccharides, L. acidophilus/fructooligosaccharides or inulin and L. rhamnosus/β-glucan oligosaccharides.

  1. Lactodifucotetraose, a human milk oligosaccharide, attenuates platelet function and inflammatory cytokine release.

    PubMed

    Newburg, David S; Tanritanir, Ayse C; Chakrabarti, Subrata

    2016-07-01

    Human milk strongly quenches inflammatory processes in vitro, and breastfed infants have lower incidence of inflammatory diseases than those fed artificially. Platelets from neonates, in contrast to those from adults, are less responsive to platelet agonists such as collagen, thrombin, ADP, and epinephrine. Breastfed infants absorb oligosaccharides intact from the human milk in their gut to the circulation. This study was to determine whether these oligosaccharides can attenuate platelet function and platelet secretion of pro-inflammatory proteins, and to identify the active component. The natural mixture of oligosaccharides from human milk and pure individual human milk oligosaccharides were tested for their ability to modulate responses of platelets isolated from human blood following exposure to thrombin, ADP, and collagen. Human milk and the natural mixture of human milk oligosaccharides inhibited platelet release of inflammatory proteins. Of the purified human milk oligosaccharides tested, only lactodifucotetraose (LDFT) significantly inhibited thrombin induced release of the pro-inflammatory proteins RANTES and sCD40L. LDFT also inhibited platelet adhesion to a collagen-coated surface, as well as platelet aggregation induced by ADP or collagen. These data indicate that LDFT may help modulate hemostasis by suppressing platelet-induced inflammatory processes in breastfed infants. This activity suggests further study of LDFT for its potential as a therapeutic agent in infants and adults.

  2. A CCD based approach to high-precision size and refractive index determination of levitated microdroplets using Fraunhofer diffraction

    SciTech Connect

    Barnes, M.D.; Lermer, N.; Whitten, W.B.; Ramsey, J.M.

    1997-06-01

    We describe a fast and convenient method of high precision size and refractive index determination of electrodynamically levitated microdroplets using Fraunhofer diffraction. The diffraction data were obtained with a 16-bit, unintensified charge coupled device (CCD) camera, and converted into angle-resolved elastic scattering intensity patterns by means of a carefully determined set of transformation parameters. The angular scattering patterns were analyzed without any {ital a priori} estimate of the droplet size and only a nominal estimate ({approx}2{percent}) of the refractive index. Experimental angular scattering patterns were fit to calculated patterns from Mie theory using a graded step-size and scaling algorithm and optimized with respect to both droplet diameter and refractive index (real part only) with a precision of {le}3 parts in 10{sup 4} and 1 part in 10{sup 3}, respectively. Potential application to quantitative fluorescence and Raman spectroscopy, as well as mixture analysis in microdroplets is discussed. {copyright} {ital 1997 American Institute of Physics.}

  3. Fixed-point single-precision estimation. [Kalman filtering for NASA Standard Spacecraft Computer orbit determination algorithm

    NASA Technical Reports Server (NTRS)

    Thompson, E. H.; Farrell, J. L.

    1976-01-01

    Monte Carlo simulation of autonomous orbit determination has validated the use of an 18-bit NASA Standard Spacecraft Computer (NSSC) for the extended Kalman filter. Dimensionally consistent scales are chosen for all variables in the algorithm, such that nearly all of the onboard computation can be performed in single precision without matrix square root formulations. Allowable simplifications in algorithm implementation and practical means of ensuring convergence are verified for accuracies of a few km provided by star/vertical observations

  4. A Study into the Method of Precise Orbit Determination of a HEO Orbiter by GPS and Accelerometer

    NASA Technical Reports Server (NTRS)

    Ikenaga, Toshinori; Hashida, Yoshi; Unwin, Martin

    2007-01-01

    In the present day, orbit determination by Global Positioning System (GPS) is not unusual. Especially for low-cost small satellites, position determination by an on-board GPS receiver provides a cheap, reliable and precise method. However, the original purpose of GPS is for ground users, so the transmissions from all of the GPS satellites are directed toward the Earth s surface. Hence there are some restrictions for users above the GPS constellation to detect those signals. On the other hand, a desire for precise orbit determination for users in orbits higher than GPS constellation exists. For example, the next Japanese Very Long Baseline Interferometry (VLBI) mission "ASTRO-G" is trying to determine its orbit in an accuracy of a few centimeters at apogee. The use of GPS is essential for such ultra accurate orbit determination. This study aims to construct a method for precise orbit determination for such high orbit users, especially in High Elliptical Orbits (HEOs). There are several approaches for this objective. In this study, a hybrid method with GPS and an accelerometer is chosen. Basically, while the position cannot be determined by an on-board GPS receiver or other Range and Range Rate (RARR) method, all we can do to estimate the user satellite s position is to propagate the orbit along with the force model, which is not perfectly correct. However if it has an accelerometer (ACC), the coefficients of the air drag and the solar radiation pressure applied to the user satellite can be updated and then the propagation along with the "updated" force model can improve the fitting accuracy of the user satellite s orbit. In this study, it is assumed to use an accelerometer available in the present market. The effects by a bias error of an accelerometer will also be discussed in this paper.

  5. Modeling radiation forces acting on TOPEX/Poseidon for precision orbit determination

    NASA Technical Reports Server (NTRS)

    Marshall, J. A.; Luthcke, S. B.; Antreasian, P. G.; Rosborough, G. W.

    1992-01-01

    Geodetic satellites such as GEOSAT, SPOT, ERS-1, and TOPEX/Poseidon require accurate orbital computations to support the scientific data they collect. Until recently, gravity field mismodeling was the major source of error in precise orbit definition. However, albedo and infrared re-radiation, and spacecraft thermal imbalances produce in combination no more than a 6-cm radial root-mean-square (RMS) error over a 10-day period. This requires the development of nonconservative force models that take the satellite's complex geometry, attitude, and surface properties into account. For TOPEX/Poseidon, a 'box-wing' satellite form was investigated that models the satellite as a combination of flat plates arranged in a box shape with a connected solar array. The nonconservative forces acting on each of the eight surfaces are computed independently, yielding vector accelerations which are summed to compute the total aggregate effect on the satellite center-of-mass. In order to test the validity of this concept, 'micro-models' based on finite element analysis of TOPEX/Poseidon were used to generate acceleration histories in a wide variety of orbit orientations. These profiles are then compared to the box-wing model. The results of these simulations and their implication on the ability to precisely model the TOPEX/Poseidon orbit are discussed.

  6. Calibration and validation of individual GOCE accelerometers by precise orbit determination

    NASA Astrophysics Data System (ADS)

    Visser, P. N. A. M.; IJssel, J. A. A. van den

    2016-01-01

    The European Space Agency Gravity field and steady-state Ocean Circular Explorer (GOCE) carries a gradiometer consisting of three pairs of accelerometers in an orthogonal triad. Precise GOCE science orbit solutions (PSO), which are based on satellite-to-satellite tracking observations by the Global Positioning System and which are claimed to be at the few cm precision level, can be used to calibrate and validate the observations taken by the accelerometers. This has been done for each individual accelerometer by a dynamic orbit fit of the time series of position co-ordinates from the PSOs, where the accelerometer observations represent the non-gravitational accelerations. Since the accelerometers do not coincide with the center of mass of the GOCE satellite, the observations have to be corrected for rotational and gravity gradient terms. This is not required when using the so-called common-mode accelerometer observations, provided the center of the gradiometer coincides with the GOCE center of mass. Dynamic orbit fits based on these common-mode accelerations therefore served as reference. It is shown that for all individual accelerometers, similar dynamic orbit fits can be obtained provided the above-mentioned corrections are made. In addition, accelerometer bias estimates are obtained that are consistent with offsets in the gravity gradients that are derived from the GOCE gradiometer observations.

  7. Precision Determination of Atmospheric Extinction at Optical and Near IR Wavelengths

    SciTech Connect

    Burke, David L.; Axelrod, T.; Blondin, Stephane; Claver, Chuck; Ivezic, Zeljko; Jones, Lynne; Saha, Abhijit; Smith, Allyn; Smith, R.Chris; Stubbs, Christopher W.; /Harvard-Smithsonian Ctr. Astrophys.

    2011-08-24

    The science goals for future ground-based all-sky surveys, such as the Dark Energy Survey, PanSTARRS, and the Large Synoptic Survey Telescope, require calibration of broadband photometry that is stable in time and uniform over the sky to precisions of a per cent or better, and absolute calibration of color measurements that are similarly accurate. This performance will need to be achieved with measurements made from multiple images taken over the course of many years, and these surveys will observe in less than ideal conditions. This paper describes a technique to implement a new strategy to directly measure variations of atmospheric transmittance at optical wavelengths and application of these measurements to calibration of ground-based observations. This strategy makes use of measurements of the spectra of a small catalog of bright 'probe' stars as they progress across the sky and back-light the atmosphere. The signatures of optical absorption by different atmospheric constituents are recognized in these spectra by their characteristic dependences on wavelength and airmass. State-of-the-art models of atmospheric radiation transport and modern codes are used to accurately compute atmospheric extinction over a wide range of observing conditions. We present results of an observing campaign that demonstrate that correction for extinction due to molecular constituents and aerosols can be done with precisions of a few millimagnitudes with this technique.

  8. Modeling radiation forces acting on TOPEX/Poseidon for precision orbit determination

    NASA Astrophysics Data System (ADS)

    Marshall, J. A.; Luthcke, S. B.; Antreasian, P. G.; Rosborough, G. W.

    1992-06-01

    Geodetic satellites such as GEOSAT, SPOT, ERS-1, and TOPEX/Poseidon require accurate orbital computations to support the scientific data they collect. Until recently, gravity field mismodeling was the major source of error in precise orbit definition. However, albedo and infrared re-radiation, and spacecraft thermal imbalances produce in combination no more than a 6-cm radial root-mean-square (RMS) error over a 10-day period. This requires the development of nonconservative force models that take the satellite's complex geometry, attitude, and surface properties into account. For TOPEX/Poseidon, a 'box-wing' satellite form was investigated that models the satellite as a combination of flat plates arranged in a box shape with a connected solar array. The nonconservative forces acting on each of the eight surfaces are computed independently, yielding vector accelerations which are summed to compute the total aggregate effect on the satellite center-of-mass. In order to test the validity of this concept, 'micro-models' based on finite element analysis of TOPEX/Poseidon were used to generate acceleration histories in a wide variety of orbit orientations. These profiles are then compared to the box-wing model. The results of these simulations and their implication on the ability to precisely model the TOPEX/Poseidon orbit are discussed.

  9. Capillary Electrophoresis of Mono- and Oligosaccharides.

    PubMed

    Toppazzini, Mila; Coslovi, Anna; Rossi, Marco; Flamigni, Anna; Baiutti, Edi; Campa, Cristiana

    2016-01-01

    This chapter reports an overview of the recent advances in the analysis of mono- and oligosaccharides by capillary electrophoresis (CE); furthermore, relevant reviews and research articles recently published in the field are tabulated. Additionally, pretreatments and procedures applied to uncharged and acidic carbohydrates (i.e., monosaccharides and lower oligosaccharides carrying carboxylate, sulfate, or phosphate groups) are described.Representative examples of such procedures are reported in detail, upon describing robust methodologies for the study of (1) neutral oligosaccharides derivatized by reductive amination and by formation of glycosylamines; (2) sialic acid derivatized with 2-aminoacridone, released from human serum immunoglobulin G; (3) anomeric couples of neutral glycosides separated using borate-based buffers; (4) unsaturated, underivatized oligosaccharides from lyase-treated alginate.

  10. Measurement of the positive muon lifetime and determination of the Fermi constant to part-per-million precision.

    PubMed

    Webber, D M; Tishchenko, V; Peng, Q; Battu, S; Carey, R M; Chitwood, D B; Crnkovic, J; Debevec, P T; Dhamija, S; Earle, W; Gafarov, A; Giovanetti, K; Gorringe, T P; Gray, F E; Hartwig, Z; Hertzog, D W; Johnson, B; Kammel, P; Kiburg, B; Kizilgul, S; Kunkle, J; Lauss, B; Logashenko, I; Lynch, K R; McNabb, R; Miller, J P; Mulhauser, F; Onderwater, C J G; Phillips, J; Rath, S; Roberts, B L; Winter, P; Wolfe, B

    2011-01-28

    We report a measurement of the positive muon lifetime to a precision of 1.0 ppm; it is the most precise particle lifetime ever measured. The experiment used a time-structured, low-energy muon beam and a segmented plastic scintillator array to record more than 2×10(12) decays. Two different stopping target configurations were employed in independent data-taking periods. The combined results give τ(μ(+)) (MuLan)=2 196 980.3(2.2)  ps, more than 15 times as precise as any previous experiment. The muon lifetime gives the most precise value for the Fermi constant: G(F) (MuLan)=1.166 378 8(7)×10(-5)  GeV(-2) (0.6 ppm). It is also used to extract the μ(-)p singlet capture rate, which determines the proton's weak induced pseudoscalar coupling g(P).

  11. Urine oligosaccharide pattern in patients with hyperprolactinaemia.

    PubMed

    Ekman, Bertil; Wahlberg, Jeanette; Landberg, Eva

    2015-11-01

    Free milk-type oligosaccharides are produced during pregnancy and lactation and may have an impact on several cells in the immune system. Our aim was to investigate if patients with isolated hyperprolactinaemia, not related to pregnancy, also have increased synthesis and urinary excretion of milk-type oligosaccharides and to compare the excretion pattern with that found during pregnancy. Urine samples were collected as morning sample from 18 patients with hyperprolactinaemia, 13 healthy controls with normal prolactin levels and four pregnant women. After purification, lactose and free oligosaccharides were analysed and quantified by high-performance anion-exchange chromatography with pulsed amperometric detection. The identity of peaks was confirmed by exoglycosidase treatment and comparison with oligosaccharide standards. Prolactin was measured in serum collected between 09 and 11 a.m. by a standardized immunochemical method. Patients with hyperprolactinaemia had higher urinary excretion of lactose than normoprolactinemic controls and urinary lactose correlated positively to prolactin levels (r = 0.51, p < 0.05). Increased levels of the fucosylated oligosaccharides 2-fucosyl lactose and lacto-di-fucotetraose were found in urine from three and two patients, respectively. The acidic oligosaccharide 3-sialyl lactose was found in high amount in urine from two patients with prolactin of >10,000 mU/l. However, pregnant women in their third trimester had the highest concentration of all these oligosaccharides and excretion increased during pregnancy. This study is first to show that both lactose and certain fucosylated and sialylated milk-type oligosaccharides are increased in some patients with hyperprolactinaemia. It remains to elucidate the functional importance of these findings.

  12. The use of laser altimetry data in Chang'E-1 precision orbit determination

    NASA Astrophysics Data System (ADS)

    Chang, Sheng-Qi; Huang, Yong; Li, Pei-Jia; Hu, Xiao-Gong; Fan, Min

    2016-09-01

    Accurate altimetric measurement not only can be applied to the calculation of a topography model but also can be used to improve the quality of the orbit reconstruction in the form of crossovers. Altimetry data from the Chang'E-1 (CE-1) laser altimeter are analyzed in this paper. The differences between the crossover constraint equation in the form of height discrepancies and in the form of minimum distances are mainly discussed. The results demonstrate that the crossover constraint equation in the form of minimum distances improves the CE-1 orbit precision. The overlap orbit performance has increased ˜ 30% compared to the orbit using only tracking data. External assessment using the topography model also shows orbit improvement. The results will be helpful for recomputing ephemeris and improving the CE-1 topography model.

  13. Determination of Personalized IOL-Constants for the Haigis Formula under Consideration of Measurement Precision

    PubMed Central

    Leydolt, Christina; Menapace, Rupert; Eppig, Timo; Langenbucher, Achim

    2016-01-01

    The capabilities of a weighted least squares approach for the optimization of the intraocular lens (IOL) constants for the Haigis formula are studied in comparison to an ordinary least squares approach. The weights are set to the inverse variances of the effective optical anterior chamber depth. The effect of random measurement noise is simulated 100000 times using data from N = 69 cataract patients and the measurement uncertainty of two different biometers. A second, independent data set (N = 33) is used to show the differences that can be expected between both methods. The weighted least squares formalism reduces the effect of measurement error on the final constants. In more than 64% it will result in a better approximation, if the measurement errors are estimated correctly. The IOL constants can be calculated with higher precision using the weighted least squares method. PMID:27391100

  14. Jason-1 Precise Orbit Determination from GPS Tracking: Method, Performance and Calibration of the Lc Phase Center Offset

    NASA Technical Reports Server (NTRS)

    Luthcke, Scott B.

    2002-01-01

    Jason-1, launched on December 7, 2001, is continuing the time series of centimeter level Ocean topography observations as the follow-on to the highly successful TOPEX/POSEIDON (T/P) radar altimeter satellite. The precision orbit determination (POD) is a critical component to meeting the Ocean topography goals of the mission. T/P has demonstrated that the time variation of Ocean topography can be determined with an accuracy of a few centimeters, thanks to the availability of highly accurate orbits based primarily on SLR+DORIS tracking. The Jason-1 mission is intended to continue measurement of the Ocean surface with the same, if not better accuracy.

  15. Calorimetric system for high-precision determination of activity of the 51Cr neutrino source in the BEST experiment

    NASA Astrophysics Data System (ADS)

    Veretenkin, E. P.; Gavrin, V. N.; Danshin, S. N.; Ibragimova, T. V.; Kalashnikova, A. A.; Kozlova, J. P.; Martynov, A. A.

    2017-01-01

    The calorimetric system based on mass-flow calorimeter for high-precision determination of neutrino flux from 51Cr source with activity 3MCi and higher is created for experiment BEST. The achieved heat release uncertainties are less than 0.25% in the whole range of the heat power and less than 0.1% in the range of 250-500 W. Total value the uncertainty considering the uncertainty of the energy release in the 51Cr decay (0.23%) shows that the activity of 3MCi 51Cr neutrino source can be determined with accuracy better than 0.5%.

  16. Precise Determination of 40Ti Mass by Measuring the 40Sc Isospin Analogue State

    NASA Astrophysics Data System (ADS)

    Liu, Wei-Ping; Hellström, M.; Collatz, R.; Benlliure, J.; Chulkov, L.; Cortina Gil, D.; Farget, F.; Grawe, H.; Z., Hu; Iwasa, N.; Pfützner, M.; Piechaczek, A.; Raabe, R.; Reusen, I.; Roeckl, E.; Vancraeynest, G.; Wöhr, A.

    2001-11-01

    The mass of 40Ti has been determined by using the isobaric multiplet mass equation method. The experimental data of the 40Ti β-decay were used to determine the level of the isospin analogue state of 40Sc. The ground-state mass excess and the QEC value for 40Ti were determined to be -9060+/-12 keV and 11 466 +/- 13 keV, respectively.

  17. Kinetic characterization of Aspergillus niger chitinase CfcI using a HPAEC-PAD method for native chitin oligosaccharides.

    PubMed

    van Munster, Jolanda M; Sanders, Peter; ten Kate, Geralt A; Dijkhuizen, Lubbert; van der Maarel, Marc J E C

    2015-04-30

    The abundant polymer chitin can be degraded by chitinases (EC 3.2.1.14) and β-N-acetyl-hexosaminidases (EC 3.2.1.52) to oligosaccharides and N-acetyl-glucosamine (GlcNAc) monomers. Kinetic characterization of these enzymes requires product quantification by an assay method with a low detection limit, preferably compatible with the use of native, non-labeled substrates. Here we report a quantitative HPAEC-PAD method that allows fast separation of chitin oligosaccharides (COS) ranging from (GlcNac)1-6 at detection limits of 1-3 pmol and a linear range of 5-250 pmol. Quantification under intra- and interday precision conditions was performed with 2.1-5.4% relative standard deviation (RSD) and 1.2-10.3% RSD, respectively. This method was successfully used for the determination of the kinetic parameters of the Aspergillus niger chitinase CfcI with native COS. CfcI was recently shown to release GlcNAc from the reducing end of COS, a new activity for fungal chitinases. A Carbohydrate Binding Module of family 18 (CBM18) is inserted in the CfcI catalytic domain. Site directed mutagenesis was used to assess the functionality of this CfcI-CBM18: four of its key amino acids were replaced by glycine residues, yielding CfcISYNF. Comparison of the kinetic parameters of CfcI and CfcISYNF confirmed that this CBM18 is functionally involved in catalysis.

  18. Gliding Motility of Mycoplasma mobile on Uniform Oligosaccharides

    PubMed Central

    Kasai, Taishi; Hamaguchi, Tasuku

    2015-01-01

    ABSTRACT The binding and gliding of Mycoplasma mobile on a plastic plate covered by 53 uniform oligosaccharides were analyzed. Mycoplasmas bound to and glided on only 21 of the fixed sialylated oligosaccharides (SOs), showing that sialic acid is essential as the binding target. The affinities were mostly consistent with our previous results on the inhibitory effects of free SOs and suggested that M. mobile recognizes SOs from the nonreducing end with four continuous sites as follows. (i and ii) A sialic acid at the nonreducing end is tightly recognized by tandemly connected two sites. (iii) The third site is recognized by a loose groove that may be affected by branches. (iv) The fourth site is recognized by a large groove that may be enhanced by branches, especially those with a negative charge. The cells glided on uniform SOs in manners apparently similar to those of the gliding on mixed SOs. The gliding speed was related inversely to the mycoplasma's affinity for SO, suggesting that the detaching step may be one of the speed determinants. The cells glided faster and with smaller fluctuations on the uniform SOs than on the mixtures, suggesting that the drag caused by the variation in SOs influences gliding behaviors. IMPORTANCE Mycoplasma is a group of bacteria generally parasitic to animals and plants. Some Mycoplasma species form a protrusion at a pole, bind to solid surfaces, and glide in the direction of the protrusion. These procedures are essential for parasitism. Usually, mycoplasmas glide on mixed sialylated oligosaccharides (SOs) derived from glycoprotein and glycolipid. Since gliding motility on uniform oligosaccharides has never been observed, this study gives critical information about recognition and interaction between receptors and SOs. PMID:26148712

  19. Structure-Function Relationships of Human Milk Oligosaccharides123

    PubMed Central

    Bode, Lars; Jantscher-Krenn, Evelyn

    2012-01-01

    Human milk contains more than a hundred structurally distinct oligosaccharides. In this review, we provide examples of how the structural characteristics of these human milk oligosaccharides (HMO) determine functionality. Specific α1–2-fucosylated HMO have been shown to serve as antiadhesive antimicrobials to protect the breast-fed infant against infections with Campylobacter jejuni, one of the most common causes of bacterial diarrhea. In contrast, α1–2-fucosylation may abolish the beneficial effects of HMO against Entamoeba histolytica, a protozoan parasite that causes colitis, acute dysentery, or chronic diarrhea. In a different context, HMO need to be both fucosylated and sialylated to reduce selectin-mediated leukocyte rolling, adhesion, and activation, which may protect breast-fed infants from excessive immune responses. In addition, our most recent data show that a single HMO that carries not 1 but 2 sialic acids protects neonatal rats from necrotizing enterocolitis, one of the most common and often fatal intestinal disorders in preterm infants. Oligosaccharides currently added to infant formula are structurally different from the oligosaccharides naturally occurring in human milk. Thus, it appears unlikely that they can mimic some of the structure-specific effects of HMO. Recent advances in glycan synthesis and isolation have increased the availability of certain HMO tri- and tetrasaccharides for in vitro and in vivo preclinical studies. In the end, intervention studies are needed to confirm that the structure-specific effects observed at the laboratory bench translate into benefits for the human infant. Ultimately, breastfeeding remains the number one choice to nourish and nurture our infants. PMID:22585916

  20. High-precision method for determining the position of laser beam focal plane

    SciTech Connect

    Malashko, Ya I; Kleimenov, A N; Potemkin, I B; Khabibulin, V M

    2013-12-31

    The method of wavefront doubled-frequency spherical modulation for determining the laser beam waist position has been simulated and experimentally studied. The error in determining the focal plane position is less than 10{sup -5} D. The amplitude of the control doubled-frequency electric signal is experimentally found to correspond to 12% of the total radiation power. (laser beams)

  1. New physics effects in tree-level decays and the precision in the determination of the quark mixing angle γ

    NASA Astrophysics Data System (ADS)

    Brod, Joachim; Lenz, Alexander; Tetlalmatzi-Xolocotzi, Gilberto; Wiebusch, Martin

    2015-08-01

    We critically review the assumption that no new physics is acting in tree-level B -meson decays and study the consequences for the ultimate precision in the direct determination of the Cabibbo-Kobayashi-Maskawa (CKM) angle γ . In our exploratory study we find that sizeable universal new physics contributions, Δ C1 ,2, to the tree-level Wilson coefficients C1 ,2 of the effective Hamiltonian describing weak decays of the b quark are currently not excluded by experimental data. In particular, we find that Im Δ C1 and Im Δ C2 can easily be of order ±10 % without violating any constraints from data. Such a size of new physics effects in C1 and C2 corresponds to an intrinsic uncertainty in the CKM angle γ of the order of |δ γ |≈4 ° , which is slightly below the current experimental precision. The accuracy in the determination of γ can be improved by putting stronger constraints on the tree-level Wilson coefficients, in particular C1. To this end we suggest a more refined theoretical study as well as more precise measurements of the observables that currently provide the strongest bounds on hypothetical new weak phases in C1 and C2. We note that the semileptonic C P asymmetries seem to have the best prospect for improving the bound on the weak phase in C1.

  2. Precision laser surveying instrument using atmospheric turbulence compensation by determining the absolute displacement between two laser beam components

    DOEpatents

    Veligdan, James T.

    1993-01-01

    Atmospheric effects on sighting measurements are compensated for by adjusting any sighting measurements using a correction factor that does not depend on atmospheric state conditions such as temperature, pressure, density or turbulence. The correction factor is accurately determined using a precisely measured physical separation between two color components of a light beam (or beams) that has been generated using either a two-color laser or two lasers that project different colored beams. The physical separation is precisely measured by fixing the position of a short beam pulse and measuring the physical separation between the two fixed-in-position components of the beam. This precisely measured physical separation is then used in a relationship that includes the indexes of refraction for each of the two colors of the laser beam in the atmosphere through which the beam is projected, thereby to determine the absolute displacement of one wavelength component of the laser beam from a straight line of sight for that projected component of the beam. This absolute displacement is useful to correct optical measurements, such as those developed in surveying measurements that are made in a test area that includes the same dispersion effects of the atmosphere on the optical measurements. The means and method of the invention are suitable for use with either single-ended systems or a double-ended systems.

  3. Precise Determination of the Baseline Between the TerraSAR-X and TanDEM-X Satellites

    NASA Astrophysics Data System (ADS)

    Koenig, Rolf; Rothacher, Markus; Michalak, Grzegorz; Moon, Yongjin

    TerraSAR-X, launched on June 15, 2007, and TanDEM-X, to be launched in September 2009, both carry the Tracking, Occultation and Ranging (TOR) category A payload instrument package. The TOR consists of a high-precision dual-frequency GPS receiver, called Integrated GPS Occultation Receiver (IGOR), for precise orbit determination and atmospheric sounding and a Laser retro-reflector (LRR) serving as target for the global Satellite Laser Ranging (SLR) ground station network. The TOR is supplied by the GeoForschungsZentrum Potsdam (GFZ) Germany, and the Center for Space Research (CSR), Austin, Texas. The objective of the German/US collaboration is twofold: provision of atmospheric profiles for use in numerical weather predictions and climate studies from the occultation data and precision SAR data processing based on precise orbits and atmospheric products. For the scientific objectives of the TanDEM- X mission, i.e., bi-static SAR together with TerraSAR-X, the dual-frequency GPS receiver is of vital importance for the millimeter level determination of the baseline or distance between the two spacecrafts. The paper discusses the feasibility of generating millimeter baselines by the example of GRACE, where for validation the distance between the two GRACE satellites is directly available from the micrometer-level intersatellite link measurements. The distance of the GRACE satellites is some 200 km, the distance of the TerraSAR-X/TanDEM-X formation will be some 200 meters. Therefore the proposed approach is then subject to a simulation of the foreseen TerraSAR-X/TanDEM-X formation. The effect of varying space environmental conditions, of possible phase center variations, multi path, and of varying center of mass of the spacecrafts are evaluated and discussed.

  4. Precise, fast, and flexible determination of protein interactions by affinity capillary electrophoresis: part 3: anions.

    PubMed

    Xu, Yuanhong; Redweik, Sabine; El-Hady, Deia Abd; Albishri, Hassan M; Preu, Lutz; Wätzig, Hermann

    2014-08-01

    The binding of physiologically anionic species or negatively charged drug molecules to proteins is of great importance in biochemistry and medicine. Since affinity capillary electrophoresis (ACE) has already proven to be a suitable analytical tool to study the influence of ions on proteins, this technique was applied here for comprehensively studying the influence of various anions on proteins of BSA, β-lactoglobulin, ovalbumin, myoglobin, and lysozyme. The analysis was performed using different selected anions of succinate, glutamate, phosphate, acetate, nitrate, iodide, thiocyanate, and pharmaceuticals (salicylic acid, aspirin, and ibuprofen) that exist in the anionic form at physiological pH 7.4. Due to the excellent repeatability and precision of the ACE measurements, not necessarily strong but significant influences of the anions on the proteins were found in many cases. Different influences in the observed bindings indicated change of charge, mass, or conformational changes of the proteins due to the binding with the studied anions. Combining the mobility-shift and pre-equilibrium ACE modes, rapidity and reversibility of the protein-anion bindings were discussed. Further, circular dichroism has been used as an orthogonal approach to characterize the interactions between the studied proteins and anions to confirm the ACE results. Since phosphate and various anions from amino acids and small organic acids such as succinate or acetate are present in very high concentrations in the cellular environment, even weak influences are certainly relevant as well.

  5. Interlaboratory assessment of measurement precision and bias in the coulometric Karl Fischer determination of water.

    PubMed

    Margolis, Sam A; Angelo, Jacob B

    2002-10-01

    The precision and bias of the coulometric Karl Fischer ASTM method D1533-00 have been assessed in a collaborative ASTM round robin program for a group of 34 laboratories. The test materials used in this study included water saturated 1-octanol (WSO), water saturated 1-butanol (WSB), and a series of new and used transformer oil samples. Fundamental systematic biases have been demonstrated in the accuracy of the measurement of water in the WSO, WSB, and transformer oil samples. The systematic bias in the measurement of the WSO and WSB standards indicates that for some laboratories either the instruments were not accurate or the quantity of the standard was not measured accurately. A second type of systematic bias consisted of measurement errors associated with the selection of the Karl Fischer solvent that was used with each instrument, and this was superimposed upon the error in the measurement of the water in the standards. Using the statistical calculation method ASTM D 6300 the repeatability and reproducibility for water in transformer oil were found to be 7 mg/kg and 14 mg/kg respectively. The method detection limit of water was 8 mg/kg oil. The method bias was estimated based on the National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 2890, WSO, since no suitable reference material for water in transformer oil was available for this study.

  6. Composite tube and plate manufacturing repeatability as determined by precision measurements of thermal strain

    NASA Astrophysics Data System (ADS)

    Riddle, Lenn A.; Tucker, James R.; Bluth, A. Marcel

    2013-09-01

    Composite materials often carry the reputation of demonstrating high variability in critical material properties. The JWST telescope metering structure is fabricated of several thousand separate composite piece parts. The stringent dimensional stability requirements on the metering structure require the critical thermal strain response of every composite piece be verified either at the billet or piece part level. JWST is a unique composite space structure in that it has required the manufacturing of several hundred composite billets that cover many lots of prepreg and many years of fabrication. The flight billet thermal expansion acceptance criteria limits the coefficient of thermal expansion (CTE) to a tolerance ranging between +/-0.014 ppm/K to +/-0.04 ppm/K around a prescribed nominal when measured from 293 K down to 40 K. The different tolerance values represent different material forms including flat plates and different tube cross-section dimensions. A precision measurement facility was developed that could measure at the required accuracy and at a pace that supported the composite part fabrication rate. The test method and facility is discussed and the results of a statistical process analysis of the flight composite billets are surveyed.

  7. Fabry-Perot Based Differential Radiometers for Precise Determination of Atmospheric Column

    NASA Technical Reports Server (NTRS)

    Heaps, William S.; Wilson, Emily L.; Goergieva, Elena

    2006-01-01

    We have developed at Goddard over the last 5 years a new type of remote sensing instrument based upon the Fabry-Perot interferometer that has broad applicability to a variety of problems of great current interest. The instrument detects absorption features of various atmospheric trace species in direct or reflected sunlight. The Fabry-Perot offers high resolution and high optical throughput with small size and simplicity of operation. We have developed instruments for use as ground based, airborne and satellite sensors for species such as carbon dioxide, oxygen and water vapor. Our current concentration is to develop an ultra precise, inexpensive, ground based device suitable for wide deployment as a validation instrument for the OCO satellite scheduled to launch in 2008. We shall show sensitivity measurements for these three species, compare our water vapor measurements to those obtained using other types of sensors and discuss some of the peculiarities that must be addressed in order to provide the very high quality column measurements required to validate the OCO carbon dioxide measurements.

  8. Precise determination of the phase boundary between coesite and stishovite in SiO2

    NASA Astrophysics Data System (ADS)

    Ono, Shigeaki; Kikegawa, Takumi; Higo, Yuji; Tange, Yoshinori

    2017-03-01

    The phase boundary between coesite and stishovite in SiO2 was determined over the range of 1200-1700 K using a multi-anvil high-pressure apparatus combined with the synchrotron X-ray diffraction technique. The stability of each phase was determined by observing the powdered X-ray diffraction data. The transition boundary between the coesite and stishovite phases was found to occur at P (GPa) = 4.7 + 0.0031 × T (K). The transition pressure determined in this study was in general agreement with what was observed in previous high-pressure experiments and heat capacity measurements. However, the slope of the transition, dP/dT, determined in our study was higher than that estimated in a previous study utilized with the in situ X-ray method. In contrast, the slope calculated by the heat capacity data was in good agreement with that determined in our study. The phase transition determined in our study occurs at around 10 GPa at the normal mantle geotherm, coinciding with the seismic discontinuity around 300 km depth known as the X-discontinuity.

  9. A fingerprinting method for chondroitin/dermatan sulfate and hyaluronan oligosaccharides.

    PubMed

    Lauder, R M; Huckerby, T N; Nieduszynski, I A

    2000-04-01

    A previously published method for the analysis of glycosaminoglycan disaccharides by high pH anion exchange chromatography (Midura,R.J., Salustri,A., Calabro,A., Yanagishita,M. and Hascall,V.C. (1994), Glycobiology,4, 333-342) has been modified and calibrated for chondroitin and dermatan sulfate oligosaccharides up to hexasaccharide in size and hyaluronan oligosaccharides up to hexadecasaccharide. For hyaluronan oligosaccharides chain length controls elution position; however, for chondroitin and dermatan sulfate oligosaccharides elution times primarily depend upon the level of sulfation, although chain length and hence charge density plays a role. The sulfation position of GalNAc residues within an oligosaccharide is also important in determining its elution position. Compared to 4-sulfation a reducing terminal 6-sulfate retards elution; however, when present on an internal GalNAc residue it is the 4-sulfate containing oligosaccharide which elutes later. These effects allow discrimination between oligosaccharides differing only in the position of GalNAc sulfation. Using this simple methodology, a Dionex CarboPac PA-1 column with NaOH/NaCl eluents and detection by absorbance at 232 nm, a quantitative analytical fingerprint of a chondroitin/dermatan sulfate chain may be obtained, allowing a determination of the abundance of chondroitin sulfate, dermatan sulfate, and hyaluronan along with an analysis of structural features with a linear response to approximately 0.1 nmol. The method may readily be calibrated using either commercial disaccharides or the di- and tetrasaccharide products of a limit digest of commercial chondroitin sulfate by chondroitin ABC endolyase. Commercially available and freshly prepared shark, whale, bovine, and human cartilage chondroitin sulfates have been examined by this methodology and we have confirmed that freshly isolated shark cartilage CS contains significant amounts of the biologically important GlcA2Sbeta(1-3)GalNAc6S structure.

  10. Precise determination of earth's center of mass using measurements from the Global Positioning System

    NASA Technical Reports Server (NTRS)

    Vigue, Yvonne; Lichten, Stephen M.; Blewitt, Geoffrey; Heflin, Michael B.; Malla, Rajendra P.

    1992-01-01

    Global Positioning System (GPS) data from a worldwide geodetic experiment were collected during a 3-week period early in 1991. Geocentric station coordinates were estimated using the GPS data, thus defining a dynamically determined reference frame origin which should coincide with the earth center of mass, or geocenter. The 3-week GPS average geocenter estimates agree to 7-13 cm with geocenter estimates determined from satellite laser ranging, a well-established technique. The RMS of daily GPS geocenter estimates were 4 cm for x and y, and 30 cm for z.

  11. 13 Years of TOPEX/POSEIDON Precision Orbit Determination and the 10-fold Improvement in Expected Orbit Accuracy

    NASA Technical Reports Server (NTRS)

    Lemoine, F. G.; Zelensky, N. P.; Luthcke, S. B.; Rowlands, D. D.; Beckley, B. D.; Klosko, S. M.

    2006-01-01

    Launched in the summer of 1992, TOPEX/POSEIDON (T/P) was a joint mission between NASA and the Centre National d Etudes Spatiales (CNES), the French Space Agency, to make precise radar altimeter measurements of the ocean surface. After the remarkably successful 13-years of mapping the ocean surface T/P lost its ability to maneuver and was de-commissioned January 2006. T/P revolutionized the study of the Earth s oceans by vastly exceeding pre-launch estimates of surface height accuracy recoverable from radar altimeter measurements. The precision orbit lies at the heart of the altimeter measurement providing the reference frame from which the radar altimeter measurements are made. The expected quality of orbit knowledge had limited the measurement accuracy expectations of past altimeter missions, and still remains a major component in the error budget of all altimeter missions. This paper describes critical improvements made to the T/P orbit time series over the 13-years of precise orbit determination (POD) provided by the GSFC Space Geodesy Laboratory. The POD improvements from the pre-launch T/P expectation of radial orbit accuracy and Mission requirement of 13-cm to an expected accuracy of about 1.5-cm with today s latest orbits will be discussed. The latest orbits with 1.5 cm RMS radial accuracy represent a significant improvement to the 2.0-cm accuracy orbits currently available on the T/P Geophysical Data Record (GDR) altimeter product.

  12. Shocked monazite chronometry: integrating microstructural and in situ isotopic age data for determining precise impact ages

    NASA Astrophysics Data System (ADS)

    Erickson, Timmons M.; Timms, Nicholas E.; Kirkland, Christopher L.; Tohver, Eric; Cavosie, Aaron J.; Pearce, Mark A.; Reddy, Steven M.

    2017-03-01

    situ U-Th-Pb analysis can date impact-related deformation. Monazite is, therefore, one of the few high-temperature geochronometers that can be used for accurate and precise dating of meteorite impacts.

  13. Atom-chip based quantum gravimetry for the precise determination of absolute local gravity

    NASA Astrophysics Data System (ADS)

    Abend, S.

    2015-12-01

    We present a novel technique for the precise measurement of absolute local gravity based on cold atom interferometry. Atom interferometry utilizes the interference of matter waves interrogated by laser light to read out inertial forces. Today's generation of these devices typically operate with test mass samples, that consists of ensembles of laser cooled atoms. Their performance is limited by the velocity spread and finite-size of the test masses that impose systematic uncertainties at the level of a few μGal. Rather than laser cooled atoms we employ quantum degenerate ensembles, so called Bose-Einstein condensates, as ultra-sensitive probes for gravity. These sources offer unique properties in temperature as well as in ensemble size that will allow to overcome the current limitations with the next generation of sensors. Furthermore, atom-chip technologies offer the possibility to generate Bose-Einstein condensates in a fast and reliable way. We show a lab-based prototype that uses the atom-chip itself to retro-reflect the interrogation laser and thus serving as inertial reference inside the vacuum. With this setup it is possible to demonstrate all necessary steps to measure gravity, including the preparation of the source, spanning an interferometer as well as the detection of the output signal, within an area of 1 cm3 right below the atom-chip and to analyze relevant systematic effects. In the framework of the center of excellence geoQ a next generation device is under construction at the Institut für Quantenoptik, that will allow for in-field measurements. This device will feature a state-of-the-art atom-chip source with a high-flux of ultra-cold atoms at a repetition rate of 1-2 Hz. In cooperation with the Müller group at the Institut für Erdmessung the sensor will be characterized in the laboratory first, to be ultimately employed in campaigns to measure the Fennoscandian uplift at the level of 1 μGal. The presented work is part of the center of

  14. Preparative purification of tetraantennary oligosaccharides from human asialyl orosomucoid.

    PubMed

    Stubbs, H J; Shia, M A; Rice, K G

    1997-05-01

    An approach to isolate micromole quantities of tetraantennary oligosaccharides from human orosomucoid is presented. The N-linked oligosaccharides from 500 mg of the glycoprotein were released enzymatically, desialylated, and isolated free of protein using ion exchange chromatography. The pooled oligosaccharides were converted into oligosaccharide glycosylamines by reaction with ammonium bicarbonate then coupled to BOC-tyrosine to prepare tyrosinamide oligosaccharides. These were resolved on semipreparative RP-HPLC to recover micromole quantities of six purified tyrosinamide oligosaccharides. The oligosaccharide structures were elucidated by a combination of high-field proton NMR and matrix-assisted time of flight mass spectrometry and included biantennary, triantennary, monofucosylated triantennary, tetraantennary, monofucosylated tetraantennary, and a tetraantennary containing a single polylactosamine extension. Edman degradation was utilized to reverse the tyrosinamide oligosaccharide derivatization leading to the generation of reducing oligosaccharides. These were used to characterize the elution profile of asialyl orosomucoid oligosaccharides on high pH anion exchange chromatography. This application of tyrosinamide derivatization has allowed for the first time the complete resolution of the complex oligosaccharide mixture from orosomucoid on a semipreparative scale in a single chromatogram and provide the first NMR characterization of polylactosamine tetraantennary oligosaccharide from this substrate. This study demonstrates the broad utility of the tyrosinamide derivatization to develop oligosaccharide libraries useful for probing the biological functions of glycosylation.

  15. Precise determination of the refractive index of suspended particles: light transmission as a function of refractive index mismatch

    NASA Astrophysics Data System (ADS)

    McClymer, J. P.

    2016-08-01

    Many fluids appear white because refractive index differences lead to multiple scattering. In this paper, we use safe, low-cost commercial index matching fluids to quantitatively study light transmission as a function of index mismatch, reduce multiple scattering to allow single scattering probes, and to precisely determine the index of refraction of suspended material. The transmission profile is compared with Rayleigh-Gans and Mie theory predictions. The procedure is accessible as a student laboratory project, while providing advantages over other standard methods of measuring the refractive index of an unknown nanoparticle, making it valuable to researchers.

  16. Precise orbit determination of a geosynchronous satellite by Delta VLBI method

    NASA Astrophysics Data System (ADS)

    Shiomi, T.; Kozono, S.-I.; Arimoto, Y.; Nagai, S.; Isogai, M.

    1984-07-01

    An experiment carried out to track the geosynchronous Japanese Communications Satellite for Experimental Purposes (CS) by Delta VLBI method is described. A baseline of 46 km length north-south was used, along with seven quasars as reference natural radio sources. The Delta VLBI method, the observational sensitivity of the VLBI with respect to the CS, and the experimental system are described. The errors due to system noises of the receiving systems and other sources are analyzed, and the data reduction methods and the results are presented. Differential ranges are obtained with 60 cm accuracy. Analysis of the accuracy of the orbit determination and of simulation studies demonstrates the usefulness of the Delta VLBI method for highly accurate orbit determination of a geosynchronous satellite.

  17. Precise Determination of Thicknesses of Multilayer Polyethylene Composite Materials by Terahertz Time-Domain Spectroscopy

    NASA Astrophysics Data System (ADS)

    Palka, Norbert; Krimi, Soufiene; Ospald, Frank; Miedzinska, Danuta; Gieleta, Roman; Malek, Marcin; Beigang, Rene

    2015-06-01

    The multilayer structure of an ultra-high molecular weight polyethylene (UHMWPE) composite material was investigated in the terahertz (THz) spectral range by means of time-domain spectroscopy (TDS) technique. Such structures consist of many alternating layers of fibers, each being perpendicular to the other and each having a thickness of about 50 μm. Refractive indices of two composite samples and of a sample composed of four single layers (plies) having the same fiber orientation were determined for two orthogonal orientations of the electric field in a transmission TDS system. The birefringence of a single layer was measured, and the origin of this phenomenon is discussed. Using the TDS system in reflection, the formation of many pulses shifted in time was observed originating from reflections from interfaces of successive layers caused by the periodic modulation of the refractive index along the propagation of the THz radiation. This phenomenon is theoretically described and simulated by means of a transfer matrix method (TMM). A time-domain fitting procedure was used to determine thicknesses of all layers of the composite material. The reconstructed waveform based on the optimized thicknesses shows very good agreement with the measured waveform, with typical differences between measurements and simulations between 3 and 7 μm (depending on the sample). As a result, we were able to determine the thicknesses of all layers of two multilayer (~200 plies) structures by means of the reflection TDS technology with high accuracy.

  18. Oligosaccharide binding proteins from Bifidobacterium longum subsp. infantis reveal a preference for host glycans.

    PubMed

    Garrido, Daniel; Kim, Jae Han; German, J Bruce; Raybould, Helen E; Mills, David A

    2011-03-15

    Bifidobacterium longum subsp. infantis (B. infantis) is a common member of the infant intestinal microbiota, and it has been characterized by its foraging capacity for human milk oligosaccharides (HMO). Its genome sequence revealed an overabundance of the Family 1 of solute binding proteins (F1SBPs), part of ABC transporters and associated with the import of oligosaccharides. In this study we have used the Mammalian Glycan Array to determine the specific affinities of these proteins. This was correlated with binding protein expression induced by different prebiotics including HMO. Half of the F1SBPs in B. infantis were determined to bind mammalian oligosaccharides. Their affinities included different blood group structures and mucin oligosaccharides. Related to HMO, other proteins were specific for oligomers of lacto-N-biose (LNB) and polylactosamines with different degrees of fucosylation. Growth on HMO induced the expression of specific binding proteins that import HMO isomers, but also bind blood group and mucin oligosaccharides, suggesting coregulated transport mechanisms. The prebiotic inulin induced other family 1 binding proteins with affinity for intestinal glycans. Most of the host glycan F1SBPs in B. infantis do not have homologs in other bifidobacteria. Finally, some of these proteins were found to be adherent to intestinal epithelial cells in vitro. In conclusion, this study represents further evidence for the particular adaptations of B. infantis to the infant gut environment, and helps to understand the molecular mechanisms involved in this process.

  19. The GLAS Algorithm Theoretical Basis Document for Precision Attitude Determination (PAD)

    NASA Technical Reports Server (NTRS)

    Bae, Sungkoo; Smith, Noah; Schutz, Bob E.

    2013-01-01

    The Geoscience Laser Altimeter System (GLAS) was the sole instrument for NASAs Ice, Cloud and land Elevation Satellite (ICESat) laser altimetry mission. The primary purpose of the ICESat mission was to make ice sheet elevation measurements of the polar regions. Additional goals were to measure the global distribution of clouds and aerosols and to map sea ice, land topography and vegetation. ICESat was the benchmark Earth Observing System (EOS) mission to be used to determine the mass balance of the ice sheets, as well as for providing cloud property information, especially for stratospheric clouds common over polar areas.

  20. Precision Determination of the Cabibbo-Kobayashi-Maskawa Element Vc b

    NASA Astrophysics Data System (ADS)

    Alberti, Andrea; Gambino, Paolo; Healey, Kristopher J.; Nandi, Soumitra

    2015-02-01

    We extract the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element Vcb and the most relevant parameters of the heavy quark expansion from data of inclusive semileptonic B decays. Our calculation includes the recently computed O (αsΛQCD2/mb2) corrections and a careful estimate of the residual theoretical uncertainty. Using a recent determination of the charm quark mass, we obtain |Vcb|=(42.21 ±0.78 )×1 0-3 and mbkin(1 GeV )=(4.553 ±0.020 ) GeV .

  1. Standardisation and precise determination of the half-life of (44)Sc.

    PubMed

    García-Toraño, E; Peyrés, V; Roteta, M; Sánchez-Cabezudo, A I; Romero, E; Martínez Ortega, A

    2016-03-01

    The half-life of the positron-emitter (44)Sc has been determined by following the decay rate with two measurement systems; an Ionisation Chamber and a HPGe detector. The combination of seven results gives a value of T1/2=4.042 (25)h, about 2% higher than the recommended value of T1/2=3.97 (4)h (Browne, 2011) and with a lower uncertainty. This radionuclide has also been standardised by coincidence counting, and liquid scintillation counting techniques. A (44)Ti/(44)Sc generator developed at CIEMAT was used to obtain the (44)Sc solutions used in all measurements.

  2. Precision determination of the dpi<-->NN transition strength at threshold.

    PubMed

    Strauch, Th; Amaro, F D; Anagnostopoulos, D F; Bühler, P; Covita, D S; Gorke, H; Gotta, D; Gruber, A; Hirtl, A; Indelicato, P; Le Bigot, E-O; Nekipelov, M; dos Santos, J M F; Schlesser, S; Schmid, Ph; Simons, L M; Trassinelli, M; Veloso, J F C A; Zmeskal, J

    2010-04-09

    An unusual but effective way to determine at threshold the dpi<-->NN transition strength alpha is to exploit the hadronic ground-state broadening Gamma(1s) in pionic deuterium, accessible by x-ray spectroscopy. The broadening is dominated by the true absorption channel dpi(-)-->nn, which is related to s-wave pion production pp-->dpi(+) by charge symmetry and detailed balance. Using the exotic atom circumvents the problem of Coulomb corrections to the cross section as necessary in the production experiments. Our dedicated measurement finds Gamma(1s)=(1171(-49)(+23)) meV yielding alpha=(252(-11)(+5)) microb.

  3. Oligosaccharide Binding in Escherichia coli Glycogen Synthase

    SciTech Connect

    Sheng, Fang; Yep, Alejandra; Feng, Lei; Preiss, Jack; Geiger, James H.

    2010-11-17

    Glycogen/starch synthase elongates glucan chains and is the key enzyme in the synthesis of glycogen in bacteria and starch in plants. Cocrystallization of Escherichia coli wild-type glycogen synthase (GS) with substrate ADPGlc and the glucan acceptor mimic HEPPSO produced a closed form of GS and suggests that domain-domain closure accompanies glycogen synthesis. Cocrystallization of the inactive GS mutant E377A with substrate ADPGlc and oligosaccharide results in the first oligosaccharide-bound glycogen synthase structure. Four bound oligosaccharides are observed, one in the interdomain cleft (G6a) and three on the N-terminal domain surface (G6b, G6c, and G6d). Extending from the center of the enzyme to the interdomain cleft opening, G6a mostly interacts with the highly conserved N-terminal domain residues lining the cleft of GS. The surface-bound oligosaccharides G6c and G6d have less interaction with enzyme and exhibit a more curled, helixlike structural arrangement. The observation that oligosaccharides bind only to the N-terminal domain of GS suggests that glycogen in vivo probably binds to only one side of the enzyme to ensure unencumbered interdomain movement, which is required for efficient, continuous glucan-chain synthesis.

  4. Precise equilibrium structure determination of hydrazoic acid (HN{sub 3}) by millimeter-wave spectroscopy

    SciTech Connect

    Amberger, Brent K.; Esselman, Brian J.; Woods, R. Claude; McMahon, Robert J.; Stanton, John F.

    2015-09-14

    The millimeter-wave spectrum of hydrazoic acid (HN{sub 3}) was analyzed in the frequency region of 235-450 GHz. Transitions from a total of 14 isotopologues were observed and fit using the A-reduced or S-reduced Hamiltonian. Coupled-cluster calculations were performed to obtain a theoretical geometry, as well as rotation-vibration interaction corrections. These calculated vibration-rotation correction terms were applied to the experimental rotational constants to obtain mixed theoretical/experimental equilibrium rotational constants (A{sub e}, B{sub e}, and C{sub e}). These equilibrium rotational constants were then used to obtain an equilibrium (R{sub e}) structure using a least-squares fitting routine. The R{sub e} structural parameters are consistent with a previously published R{sub s} structure, largely falling within the uncertainty limits of that R{sub s} structure. The present R{sub e} geometric parameters of HN{sub 3} are determined with exceptionally high accuracy, as a consequence of the large number of isotopologues measured experimentally and the sophisticated (coupled-cluster theoretical treatment (CCSD(T))/ANO2) of the vibration-rotation interactions. The R{sub e} structure exhibits remarkable agreement with the CCSD(T)/cc-pCV5Z predicted structure, validating both the accuracy of the ab initio method and the claimed uncertainties of the theoretical/experimental structure determination.

  5. A Complication in Determining the Precise Age of the Solar System

    NASA Astrophysics Data System (ADS)

    Brennecka, G. A.

    2010-01-01

    Primitive components in meteorites contain a detailed record of the conditions and processes in the solar nebula, the cloud of dust and gas surrounding the infant Sun. Determining accurately when the first materials formed requires the lead-lead (Pb-Pb) dating method, a method based on the decay of uranium (U) isotopes to Pb isotopes. The initial ratio of U-238 to U-235 is critical to determining the ages correctly, and many studies have concluded that the ratio is constant for any given age. However, my colleagues at Arizona State University, Institut fur Geowissenschaften, Goethe-Universitat (Frankfurt, Germany), and the Senckenberg Forschungsinstitut und Naturmuseum (also in Frankfurt) and I have found that some calcium-aluminum-rich inclusions (CAIs) in chondritic meteorites deviate from the conventional value for the U-238/U-235 ratio. This could lead to inaccuracies of up to 5 million years in the age of these objects, if no correction is made. Variations in the concentrations of thorium and neodymium with the U-238/U-235 ratio suggest that the ratio may have been lowered by the decay of curium-247, which decays to U-235 with a half-life of 15.6 million years. Curium-247 is created in certain types of energetic supernovae, so its presence suggests that a supernova added material to the pre-solar interstellar cloud between 110 and 140 million years before the Solar System began to form.

  6. The precision of a special purpose analog computer in clinical cardiac output determination.

    PubMed Central

    Sullivan, F J; Mroz, E A; Miller, R E

    1975-01-01

    Three hundred dye-dilution curves taken during our first year of clinical experience with the Waters CO-4 cardiac output computer were analyzed to estimate the errors involved in its use. Provided that calibration is accurate and 5.0 mg of dye are injected for each curve, then the percentage standard deviation of measurement using this computer is about 8.7%. Included in this are the errors inherent in the computer, errors due to baseline drift, errors in the injection of dye and acutal variation of cardiac output over a series of successive determinations. The size of this error is comparable to that involved in manual calculation. The mean value of five successive curves will be within 10% of the real value in 99 cases out of 100. Advances in methodology and equipment are discussed which make calibration simpler and more accurate, and which should also improve the quality of computer determination. A list of suggestions is given to minimize the errors involved in the clinical use of this equipment. Images Fig. 4. PMID:1089394

  7. High Fidelity Non-Gravitational Force Models for Precise and Accurate Orbit Determination of TerraSAR-X

    NASA Astrophysics Data System (ADS)

    Hackel, Stefan; Montenbruck, Oliver; Steigenberger, -Peter; Eineder, Michael; Gisinger, Christoph

    Remote sensing satellites support a broad range of scientific and commercial applications. The two radar imaging satellites TerraSAR-X and TanDEM-X provide spaceborne Synthetic Aperture Radar (SAR) and interferometric SAR data with a very high accuracy. The increasing demand for precise radar products relies on sophisticated validation methods, which require precise and accurate orbit products. Basically, the precise reconstruction of the satellite’s trajectory is based on the Global Positioning System (GPS) measurements from a geodetic-grade dual-frequency receiver onboard the spacecraft. The Reduced Dynamic Orbit Determination (RDOD) approach utilizes models for the gravitational and non-gravitational forces. Following a proper analysis of the orbit quality, systematics in the orbit products have been identified, which reflect deficits in the non-gravitational force models. A detailed satellite macro model is introduced to describe the geometry and the optical surface properties of the satellite. Two major non-gravitational forces are the direct and the indirect Solar Radiation Pressure (SRP). Due to the dusk-dawn orbit configuration of TerraSAR-X, the satellite is almost constantly illuminated by the Sun. Therefore, the direct SRP has an effect on the lateral stability of the determined orbit. The indirect effect of the solar radiation principally contributes to the Earth Radiation Pressure (ERP). The resulting force depends on the sunlight, which is reflected by the illuminated Earth surface in the visible, and the emission of the Earth body in the infrared spectra. Both components of ERP require Earth models to describe the optical properties of the Earth surface. Therefore, the influence of different Earth models on the orbit quality is assessed within the presentation. The presentation highlights the influence of non-gravitational force and satellite macro models on the orbit quality of TerraSAR-X.

  8. Xyloglucan oligosaccharides promote growth and activate cellulase: Evidence for a role of cellulase in cell expansion. [Pisum sativum L

    SciTech Connect

    McDougall, G.J.; Fry, S.C. )

    1990-07-01

    Oligosaccharides produced by the action of fungal cellulase on xyloglucans promoted the elongation of etiolated pea (Pisum sativum L.) stem segments in a straight-growth bioassay designed for the determination of auxins. The oligosaccharides were most active at about 1 micromolar. We tested the relative growth-promoting activities of four HPLC-purified oligosaccharides which shared a common glucose{sub 4} {center dot} xylose{sub 3} (XG7) core. The substituted oligosaccharides XG8 (glucose{sub 4} {center dot} xylose{sub 3} {center dot} galactose) and XG9n (glucose{sub 4} {center dot} xylose{sub 3} {center dot} galactose{sub 2}) were more effective than XG7 itself and XG9 (glucose{sub 4} {center dot} xylose{sub 3} {center dot} galactose {center dot} fucose). The same oligosaccharides also promoted the degradation, assayed viscometrically, of xyloglucan by an acidic cellulase from bean (Phaseolus vulgaris L.) leaves. The oligosaccharides were highly active at 10{sup {minus}4} molar, causing up to a fourfold increase in activity, but the effect was still detectable at 1 micromolar. Those oligosaccharides (XG8 and XG9n) which best promoted growth, stimulated cellulase activity to the greatest extent. The oligosaccharides did not stimulate the action of the cellulase in an assay based on the conversion of ({sup 3}H)xyloglucan to ethanol-soluble fragments. This suggests that the oligosaccharides enhanced the midchain hydrolysis of xyloglucan molecules (which would rapidly reduce the viscosity of the solution), at the expense of cleavage near the termini (which would yield ethanol-soluble products).

  9. Precision of dehydroascorbic acid quantitation with the use of the subtraction method--validation of HPLC-DAD method for determination of total vitamin C in food.

    PubMed

    Mazurek, Artur; Jamroz, Jerzy

    2015-04-15

    In food analysis, a method for determination of vitamin C should enable measuring of total content of ascorbic acid (AA) and dehydroascorbic acid (DHAA) because both chemical forms exhibit biological activity. The aim of the work was to confirm applicability of HPLC-DAD method for analysis of total content of vitamin C (TC) and ascorbic acid in various types of food by determination of validation parameters such as: selectivity, precision, accuracy, linearity and limits of detection and quantitation. The results showed that the method applied for determination of TC and AA was selective, linear and precise. Precision of DHAA determination by the subtraction method was also evaluated. It was revealed that the results of DHAA determination obtained by the subtraction method were not precise which resulted directly from the assumption of this method and the principles of uncertainty propagation. The proposed chromatographic method should be recommended for routine determinations of total vitamin C in various food.

  10. DETERMINATION OF INTERSTITIAL CHLORIDE IN SHALES AND CONSOLIDATED ROCKS BY A PRECISION LEACHING TECHNIQUE.

    USGS Publications Warehouse

    Manheim, Frank T.; Peck, E.E.; Lane, Candice M.

    1985-01-01

    The authors have devised a technique for determining chloride in interstitial water of consolidated rocks. Samples of rocks ranging from 5 to 10 g are crushed and sieved under controlled conditions and then ground with distilled water to submicron size in a closed mechanical mill. The chloride concentrations and total pore-water concentrations, obtained earlier from the same samples by low-temperature vacuum desiccation, are used to arrive at the 'original' pore-water chloride concentrations by a simple iteration procedure. Interstitial chlorinity results obtained from Cretaceous and Jurassic strata in the Gulf of Mexico coastal areas ranged from 20 to 100 g/kg Cl with reproducibility approaching plus or minus 1%.

  11. GPS-Based Precision Orbit Determination for a New Era of Altimeter Satellites: Jason-1 and ICESat

    NASA Technical Reports Server (NTRS)

    Luthcke, Scott B.; Rowlands, David D.; Lemoine, Frank G.; Zelensky, Nikita P.; Williams, Teresa A.

    2003-01-01

    Accurate positioning of the satellite center of mass is necessary in meeting an altimeter mission's science goals. The fundamental science observation is an altimetric derived topographic height. Errors in positioning the satellite's center of mass directly impact this fundamental observation. Therefore, orbit error is a critical Component in the error budget of altimeter satellites. With the launch of the Jason-1 radar altimeter (Dec. 2001) and the ICESat laser altimeter (Jan. 2003) a new era of satellite altimetry has begun. Both missions pose several challenges for precision orbit determination (POD). The Jason-1 radial orbit accuracy goal is 1 cm, while ICESat (600 km) at a much lower altitude than Jason-1 (1300 km), has a radial orbit accuracy requirement of less than 5 cm. Fortunately, Jason-1 and ICESat POD can rely on near continuous tracking data from the dual frequency codeless BlackJack GPS receiver and Satellite Laser Ranging. Analysis of current GPS-based solution performance indicates the l-cm radial orbit accuracy goal is being met for Jason-1, while radial orbit accuracy for ICESat is well below the 54x1 mission requirement. A brief overview of the GPS precision orbit determination methodology and results for both Jason-1 and ICESat are presented.

  12. Structures and application of oligosaccharides in human milk

    PubMed Central

    KOBATA, Akira

    2010-01-01

    Comparative study of the oligosaccharide profiles of individual human milk revealed the presence of three different patterns. Four oligosaccharides containing the Fucα1-2Gal group were missing in the milk of non-secretor, and three oligosaccharides containing the Fucα1-4GlcNAc group were missing in the milk of Lewis negative individuals. Disappearance of some major oligosaccharides in these samples led to the finding of five novel minor oligosaccharides, which were hidden under the missing oligosaccharides. Following these studies, structures of many novel milk oligosaccharides were elucidated. At least 13 core oligosaccharides were found in these oligosaccharides. By adding α-fucosyl residues and sialic acid residues to these core oligosaccharides, more than one hundred oligosaccharides were formed. All these oligosaccharides contain lactose at their reducing termini. This evidence, together with the deletion phenomena found in the milk oligosaccharides of non-secretor and Lewis negative individuals, suggested that the oligosaccharides are formed from lactose by the concerted action of glycosyltransferases, which are responsible for elongation and branching of the Galβ1-4GlcNAc group in the sugar chains of glycoconjugates on the surface of epithelial cells. Therefore, oligosaccharides in human milk could include many structures, starting from the Galβ1-4GlcNAc group in the sugar chains of various glycoconjugates. Many lines of evidence recently indicated that virulent enteric bacteria and viruses start their infection by binding to particular sugar chains of glycoconjugates on the target cell surfaces. Therefore, milk oligosaccharides could be useful for developing drugs, which inhibit the infection of bacteria and viruses. PMID:20689231

  13. Accurate and precise determination of critical properties from Gibbs ensemble Monte Carlo simulations

    SciTech Connect

    Dinpajooh, Mohammadhasan; Bai, Peng; Allan, Douglas A.; Siepmann, J. Ilja

    2015-09-21

    Since the seminal paper by Panagiotopoulos [Mol. Phys. 61, 813 (1997)], the Gibbs ensemble Monte Carlo (GEMC) method has been the most popular particle-based simulation approach for the computation of vapor–liquid phase equilibria. However, the validity of GEMC simulations in the near-critical region has been questioned because rigorous finite-size scaling approaches cannot be applied to simulations with fluctuating volume. Valleau [Mol. Simul. 29, 627 (2003)] has argued that GEMC simulations would lead to a spurious overestimation of the critical temperature. More recently, Patel et al. [J. Chem. Phys. 134, 024101 (2011)] opined that the use of analytical tail corrections would be problematic in the near-critical region. To address these issues, we perform extensive GEMC simulations for Lennard-Jones particles in the near-critical region varying the system size, the overall system density, and the cutoff distance. For a system with N = 5500 particles, potential truncation at 8σ and analytical tail corrections, an extrapolation of GEMC simulation data at temperatures in the range from 1.27 to 1.305 yields T{sub c} = 1.3128 ± 0.0016, ρ{sub c} = 0.316 ± 0.004, and p{sub c} = 0.1274 ± 0.0013 in excellent agreement with the thermodynamic limit determined by Potoff and Panagiotopoulos [J. Chem. Phys. 109, 10914 (1998)] using grand canonical Monte Carlo simulations and finite-size scaling. Critical properties estimated using GEMC simulations with different overall system densities (0.296 ≤ ρ{sub t} ≤ 0.336) agree to within the statistical uncertainties. For simulations with tail corrections, data obtained using r{sub cut} = 3.5σ yield T{sub c} and p{sub c} that are higher by 0.2% and 1.4% than simulations with r{sub cut} = 5 and 8σ but still with overlapping 95% confidence intervals. In contrast, GEMC simulations with a truncated and shifted potential show that r{sub cut} = 8σ is insufficient to obtain accurate results. Additional GEMC simulations for hard

  14. Precise orbit determination of BeiDou constellation based on BETS and MGEX network

    PubMed Central

    Lou, Yidong; Liu, Yang; Shi, Chuang; Yao, Xiuguang; Zheng, Fu

    2014-01-01

    Chinese BeiDou Navigation Satellite System is officially operational as a regional constellation with five Geostationary Earth Orbit (GEO) satellites, five Inclined Geosynchronous Satellite Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Observations from the BeiDou Experimental Tracking Stations (BETS) and the IGS Multi-GNSS Experiment (MGEX) network from 1 January to 31 March 2013 are processed for orbit determination of the BeiDou constellation. Various arc lengths and solar radiation pressure parameters are investigated. The reduced set of ECOM five-parameter model produces better performance than the full set of ECOM nine-parameter model for BeiDou IGSO and MEO. The orbit overlap for the middle days of 3-day arc solutions is better than 20 cm and 14 cm for IGSO and MEO in RMS, respectively. Satellite laser ranging residuals are better than 10 cm for both IGSO and MEO. For BeiDou GEO, the orbit overlap of several meters and satellite laser ranging residuals of several decimetres can be achieved. PMID:24733025

  15. Assessment of a non-dedicated GPS receiver system for precise airborne attitude determination

    SciTech Connect

    Cannon, M.E.; Sun, H.; Owen, T.E.; Meindl, M.A.

    1994-09-01

    The use of a non-dedicated GPS receiver system for attitude determination was assessed in airborne mode through a test conducted at Sandia National Laboratories. Four independent NovAtel GPSCard{trademark} receivers were installed in Sandia`s Twin Engine Otter with two antennas mounted on the fuselage and two on the wing tips at separations of 6 to 18 m. A strapdown INS was also on board the aircraft in order to provide an independent attitude reference at rates between 4 and 10 Hz. During the multi-day test, GPS measurements were recorded between 1 and 10 Hz. Carrier phase measurements were post-processed using a double difference approach developed at The University of Calgary in which integer ambiguities were resolved in seconds using the known antenna separations as constraints. The tracking capability of the system is demonstrated under dynamics consisting of roll and pitch angles up to 45 and 12 degrees, respectively. Comparisons between the GPS and INS attitude angles are presented for two of the test days and show agreement at the several arcminute level. Conclusions are made with respect to system accuracy and performance in an operational airborne environment.

  16. High precision optical measurement of displacement and simultaneous determinations of piezoelectric coefficients

    NASA Astrophysics Data System (ADS)

    Gamboa, Bryan M.; Malladi, Madhuri; Vadlamani, Ramya; Guo, Ruyan; Bhalla, Amar

    2016-09-01

    PZT are also well known for their applications in Micro Electrical Mechanical Systems (MEMS). It is necessary to study the piezoelectric coefficients of the materials accurately in order to design a sensor as an example, which defines their strain dependent applications. Systematic study of the electro mechanic displacement measurement was conducted and compared using a white light fiber optic sensor, a heterodyne laser Doppler vibrometer, and a homodyne laser interferometry setup. Frequency dependent measurement is conducted to evaluate displacement values well below and near the piezoelectric resonances. UHF-120 ultra-high frequency Vibrometer is used to measure the longitudinal piezoelectric displacement or x33 and the MTI 2000 FotonicTM Sensor is used to measure the transverse piezoelectric displacement or x11 over 100Hz to 2MHz. A Multiphysics Finite Element Analysis method, COMSOL, is also adopted in the study to generate a three dimensional electromechanical coupled model based on experimentally determined strains x33 and x11 as a function of frequency of the electric field applied. The full family of piezoelectric coefficients of the poled electronic ceramic PZT, d33, d31, and d15, can be then derived, upon satisfactory simulation of the COMSOL. This is achieved without the usual need of preparation of piezoelectric resonators of fundamental longitudinal, transversal, and shear modes respectively.

  17. Precise orbit determination of BeiDou constellation based on BETS and MGEX network.

    PubMed

    Lou, Yidong; Liu, Yang; Shi, Chuang; Yao, Xiuguang; Zheng, Fu

    2014-04-15

    Chinese BeiDou Navigation Satellite System is officially operational as a regional constellation with five Geostationary Earth Orbit (GEO) satellites, five Inclined Geosynchronous Satellite Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Observations from the BeiDou Experimental Tracking Stations (BETS) and the IGS Multi-GNSS Experiment (MGEX) network from 1 January to 31 March 2013 are processed for orbit determination of the BeiDou constellation. Various arc lengths and solar radiation pressure parameters are investigated. The reduced set of ECOM five-parameter model produces better performance than the full set of ECOM nine-parameter model for BeiDou IGSO and MEO. The orbit overlap for the middle days of 3-day arc solutions is better than 20 cm and 14 cm for IGSO and MEO in RMS, respectively. Satellite laser ranging residuals are better than 10 cm for both IGSO and MEO. For BeiDou GEO, the orbit overlap of several meters and satellite laser ranging residuals of several decimetres can be achieved.

  18. Chemical characterization of oligosaccharides in the milk of six species of New and Old world monkeys

    PubMed Central

    Goto, Kohta; Fukuda, Kenji; Senda, Akitsugu; Saito, Tadao; Kimura, Kazumasa; Glander, Kenneth E.; Hinde, Katie; Dittus, Wolfgang; Milligan, Lauren A.; Power, Michael L.; Oftedal, Olav T.

    2010-01-01

    Human and great ape milks contain a diverse array of milk oligosaccharides, but little is known about the milk oligosaccharides of other primates, and how they differ among taxa. Neutral and acidic oligosaccharides were isolated from the milk of three species of Old World or catarrhine monkeys (Cercopithecidae: rhesus macaque (Macaca mulatta), toque macaque (Macaca sinica) and Hamadryas baboon (Papio hamadryas)) and three of New World or platyrrhine monkeys (Cebidae: tufted capuchin (Cebus apella) and Bolivian squirrel monkey (Saimiri boliviensis); Atelidae: mantled howler (Alouatta palliata)). The milks of these species contained 6–8% total sugar, most of which was lactose: the estimated ratio of oligosaccharides to lactose in Old World monkeys (1:4 to 1:6) was greater than in New World monkeys (1:12 to 1:23). The chemical structures of the oligosaccharides were determined mainly by 1H-NMR spectroscopy. Oligosaccharides containing the type II unit (Gal(β1-4)GlcNAc) were found in the milk of the rhesus macaque, toque macaque, Hamadryas baboon and tufted capuchin, but oligosaccharides containing the type I unit (Gal(β1-3)GlcNAc), which have been found in human and many great ape milks, were absent from the milk of all species studied. Oligosaccharides containing Lewis x (Gal(β1-4)[Fuc(α1-3)]GlcNAc) and 3-fucosyl lactose (3-FL, Gal(β1-4)[Fuc(α1-3)]Glc) were found in the milk of the three cercopithecid monkey species, while 2-fucosyl lactose (5'-FL, Fuc(α1-2)Gal(β1-4)Glc) was absent from all species studied. All of these milks contained acidic oligosaccharides that had N-acetylneuraminic acid as part of their structures, but did not contain oligosaccharides that had N-glycolylneuraminic acid, in contrast to the milk or colostrum of great apes which contain both types of acidic oligosaccharides. Two GalNAc-containing oligosaccharides, lactose 3′-O-sulfate and lacto-N-novopentaose I (Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc) were found only in the

  19. Occurrence of glycine in the core oligosaccharides of Hafnia alvei lipopolysaccharides--identification of disubstituted glycoform.

    PubMed

    Gozdziewicz, Tomasz K; Man-Kupisinska, Aleksandra; Lugowski, Czesław; Lukasiewicz, Jolanta

    2015-05-18

    Endotoxins (lipopolysaccharides, LPS) are the main surface antigens and virulence factors of Gram-negative bacteria involved for example in the development of nosocomial infections and sepsis. They consist of three main regions: O-specific polysaccharide, core oligosaccharide, and lipid A. Bacteria modify LPS structure to escape the immune defence, but also to adapt to environmental conditions. LPS's structures are highly diversified in the O-specific polysaccharide region to evade bactericidal factors of immune system, but retain some common epitopes that are potential candidates for therapeutic strategies against bacterial infections. Common occurrence of glycine within the structure of LPS is a known phenomenon and was previously reported for variety of species. Since glycine residue substitutes mainly core oligosaccharide of LPS, especially inner core region, it was also considered as a part of common epitope for broad-reactive antimicrobial antibodies. Herein, we used multiple-stage electrospray ionisation mass spectrometry to identify glycine substitution in core oligosaccharide type characteristic for Hafnia alvei LPS, and isolated from five strains of different O-serotypes: 32, PCM 1190, PCM 1192, PCM 1200, and PCM 1209. The location of glycine in core oligosaccharide was determined in detail for LPS 1190 using ESI-MS(n). Three glycoforms were identified, including two mono-glycinylated and one diglycinylated core oligosaccharides.

  20. Achieving and Validating the 1-centimeter Orbit: JASON-1 Precision Orbit Determination Using GPS, SLR, DORIS and Altimeter data

    NASA Technical Reports Server (NTRS)

    Luthcke, Scott B.; Zelensky, Nikita P.; Rowlands, David D.; Lemoine, Frank G.; Williams, Teresa A.

    2003-01-01

    Jason-1, launched on December 7, 2001, is continuing the time series of centimeter level ocean topography observations as the follow-on to the highly successful TOPEX/POSEIDON (T/P) radar altimeter satellite. The precision orbit determination (POD) is a critical component to meeting the ocean topography goals of the mission. Jason-1 is no exception and has set a 1 cm radial orbit accuracy goal, which represents a factor of two improvement over what is currently being achieved for T/P. The challenge to precision orbit determination (POD) is both achieving the 1 cm radial orbit accuracy and evaluating and validating the performance of the 1 cm orbit. Fortunately, Jason-1 POD can rely on four independent tracking data types including near continuous tracking data from the dual frequency codeless BlackJack GPS receiver. In addition, to the enhanced GPS receiver, Jason-1 carries significantly improved SLR and DORIS tracking systems along with the altimeter itself. We demonstrate the 1 cm radial orbit accuracy goal has been achieved using GPS data alone in a reduced dynamic solution. It is also shown that adding SLR data to the GPS-based solutions improves the orbits even further. In order to assess the performance of these orbits it is necessary to process all of the available tracking data (GPS, SLR, DORIS and altimeter crossover differences) as either dependent or independent of the orbit solutions. It was also necessary to compute orbit solutions using various combinations of the four available tracking data in order to independently assess the orbit performance. Towards this end, we have greatly improved orbits determined solely from SLR+DORIS data by applying the reduced dynamic solution strategy. In addition, we have computed reduced dynamic orbits based on SLR, DORIS and crossover data that are a significant improvement over the SLR and DORIS based dynamic solutions. These solutions provide the best performing orbits for independent validation of the GPS

  1. Thermospheric density estimation and responses to the March 2013 geomagnetic storm from GRACE GPS-determined precise orbits

    NASA Astrophysics Data System (ADS)

    Calabia, Andres; Jin, Shuanggen

    2017-02-01

    The thermospheric mass density variations and the thermosphere-ionosphere coupling during geomagnetic storms are not clear due to lack of observables and large uncertainty in the models. Although accelerometers on-board Low-Orbit-Earth (LEO) satellites can measure non-gravitational accelerations and derive thermospheric mass density variations with unprecedented details, their measurements are not always available (e.g., for the March 2013 geomagnetic storm). In order to cover accelerometer data gaps of Gravity Recovery and Climate Experiment (GRACE), we estimate thermospheric mass densities from numerical derivation of GRACE determined precise orbit ephemeris (POE) for the period 2011-2016. Our results show good correlation with accelerometer-based mass densities, and a better estimation than the NRLMSISE00 empirical model. Furthermore, we statistically analyze the differences to accelerometer-based densities, and study the March 2013 geomagnetic storm response. The thermospheric density enhancements at the polar regions on 17 March 2013 are clearly represented by POE-based measurements. Although our results show density variations better correlate with Dst and k-derived geomagnetic indices, the auroral electroject activity index AE as well as the merging electric field Em picture better agreement at high latitude for the March 2013 geomagnetic storm. On the other side, low-latitude variations are better represented with the Dst index. With the increasing resolution and accuracy of Precise Orbit Determination (POD) products and LEO satellites, the straightforward technique of determining non-gravitational accelerations and thermospheric mass densities through numerical differentiation of POE promises potentially good applications for the upper atmosphere research community.

  2. Centimeter-level precise orbit determination for the HY-2A satellite using DORIS and SLR tracking data

    NASA Astrophysics Data System (ADS)

    Kong, Qiaoli; Guo, Jinyun; Sun, Yu; Zhao, Chunmei; Chen, Chuanfa

    2017-01-01

    The HY-2A satellite is the first ocean dynamic environment monitoring satellite of China. Centimeter-level radial accuracy is a fundamental requirement for its scientific research and applications. To achieve this goal, we designed the strategies of precise orbit determination (POD) in detail. To achieve the relative optimal orbit for HY-2A, we carried out POD using DORIS-only, SLR-only, and DORIS + SLR tracking data, respectively. POD tests demonstrated that the consistency level of DORIS-only and SLR-only orbits with respect to the CNES orbits were about 1.81 cm and 3.34 cm in radial direction in the dynamic sense, respectively. We designed 6 cases of different weight combinations for DORIS and SLR data, and found that the optimal relative weight group was 0.2 mm/s for DORIS and 15.0 cm for SLR, and RMS of orbit differences with respect to the CNES orbits in radial direction and three-dimensional (3D) were 1.37 cm and 5.87 cm, respectively. These tests indicated that the relative radial and 3D accuracies computed using DORIS + SLR data with the optimal relative weight set were obviously higher than those computed using DORIS-only and SLR-only data, and satisfied the requirement of designed precision. The POD for HY-2A will provide the invaluable experience for the following HY-2B, HY-2C, and HY-2D satellites.

  3. Precise Determination of the Direct-Indirect Band Gap Energy Crossover In AlxGa1-xAs

    NASA Astrophysics Data System (ADS)

    Fluegel, Brian; Beaton, Daniel; Alberi, Kirstin; Mascarenhas, Angelo

    2014-03-01

    AlxGa1-xAs is a technologically important semiconductor material system for optoelectronic applications due to its type I band alignment with GaAs under nearly lattice-matched conditions. Heterostructure design often relies on exactly controlling the relative positions of the Γ and X conduction band edges, yet despite over three decades of research on this alloy, the precise energy and composition of the direct-indirect band gap crossover is still not well resolved. We report the results of our most recent investigation of AlxGa1-xAs (0.28 < x<0.42) epitaxial films, in which the observation of concurrent photoluminescence (PL) emission peaks from the direct and indirect band gaps combined with time-resolved PL information yields a precise determination of the direct-indirect band gap crossover energy and composition. This work was supported by the DOE Office of Science, Basic Energy Sciences under contract DE-AC36-08GO28308. Acknowledgement: the samples were provided by John Reno from Sandia National Laboratory.

  4. In vitro evaluation of the fermentation properties and potential prebiotic activity of caprine cheese whey oligosaccharides in batch culture systems.

    PubMed

    Oliveira, Diana L; Costabile, Adele; Wilbey, R Andrew; Grandison, Alistair S; Duarte, Luis C; Roseiro, Luisa B

    2012-01-01

    The prebiotic effect of oligosaccharides recovered and purified from caprine whey, was evaluated by in vitro fermentation under anaerobic conditions using batch cultures at 37°C with human faeces. Effects on key gut bacterial groups were monitored over 24 h by fluorescence in situ hybridization (FISH), which was used to determine a quantitative prebiotic index score. Production of short-chain fatty acids (SCFAs) as fermentation end products was analyzed by high-performance liquid chromatography (HPLC). Growth of Bifidobacterium spp was significantly higher (P ≥ 0.05) with the purified oligosaccharides compared to the negative control. Lactic and propionic acids were the main SCFAs produced. Antimicrobial activity of the oligosaccharides was also tested, revealing no inhibition though a decrease in Staphylococcus aureus and Escherichia coli growth. These findings indicate that naturally extracted oligosaccharides from caprine whey could be used as new and valuable source of prebiotics.

  5. Influence of the physico-chemical characteristics of chito-oligosaccharides (COS) on antioxidant activity.

    PubMed

    Mengíbar, Marian; Mateos-Aparicio, Inmaculada; Miralles, Beatriz; Heras, Angeles

    2013-09-12

    Chito-oligosaccharides (COS) are being used as important functional materials for many applications due to their bioactivities. The aim of this research has been to assess the relationship between the physico-chemical characteristics, average molecular weight (Mw), acetylation degree (DA), polymerization degree (DP) and specially sequence composition determined by MALDI-TOF MS and the antioxidant properties of COS. These oligosaccharides were obtained by enzymatic depolymerization with chitosanase and lysozyme using a specific chitosan and its reacetylated product. The COS fraction below 5 kDa obtained from chitosanase depolymerization showed the highest capacity to scavenge DPPH radicals and to reduce Fe(3+). A correlation was found between the relative amount of molecules with a given A/D (acetylated vs deacetylated units) ratio within the COS and their antioxidant activity, which could be used to predict the antioxidant behavior of a fraction of chito-oligosaccharides.

  6. Exploration of conformational spaces of high-mannose-type oligosaccharides by an NMR-validated simulation.

    PubMed

    Yamaguchi, Takumi; Sakae, Yoshitake; Zhang, Ying; Yamamoto, Sayoko; Okamoto, Yuko; Kato, Koichi

    2014-10-06

    Exploration of the conformational spaces of flexible biomacromolecules is essential for quantitatively understanding the energetics of their molecular recognition processes. We employed stable isotope- and lanthanide-assisted NMR approaches in conjunction with replica-exchange molecular dynamics (REMD) simulations to obtain atomic descriptions of the conformational dynamics of high-mannose-type oligosaccharides, which harbor intracellular glycoprotein-fate determinants in their triantennary structures. The experimentally validated REMD simulation provided quantitative views of the dynamic conformational ensembles of the complicated, branched oligosaccharides, and indicated significant expansion of the conformational space upon removal of a terminal mannose residue during the functional glycan-processing pathway.

  7. Automated synthesis of arabinoxylan-oligosaccharides enables characterization of antibodies that recognize plant cell wall glycans.

    PubMed

    Schmidt, Deborah; Schuhmacher, Frank; Geissner, Andreas; Seeberger, Peter H; Pfrengle, Fabian

    2015-04-07

    Monoclonal antibodies that recognize plant cell wall glycans are used for high-resolution imaging, providing important information about the structure and function of cell wall polysaccharides. To characterize the binding epitopes of these powerful molecular probes a library of eleven plant arabinoxylan oligosaccharides was produced by automated solid-phase synthesis. Modular assembly of oligoarabinoxylans from few building blocks was enabled by adding (2-naphthyl)methyl (Nap) to the toolbox of orthogonal protecting groups for solid-phase synthesis. Conjugation-ready oligosaccharides were obtained and the binding specificities of xylan-directed antibodies were determined on microarrays.

  8. Measurement of muon capture on the proton to 1% precision and determination of the pseudoscalar coupling gP.

    PubMed

    Andreev, V A; Banks, T I; Carey, R M; Case, T A; Clayton, S M; Crowe, K M; Deutsch, J; Egger, J; Freedman, S J; Ganzha, V A; Gorringe, T; Gray, F E; Hertzog, D W; Hildebrandt, M; Kammel, P; Kiburg, B; Knaack, S; Kravtsov, P A; Krivshich, A G; Lauss, B; Lynch, K R; Maev, E M; Maev, O E; Mulhauser, F; Petitjean, C; Petrov, G E; Prieels, R; Schapkin, G N; Semenchuk, G G; Soroka, M A; Tishchenko, V; Vasilyev, A A; Vorobyov, A A; Vznuzdaev, M E; Winter, P

    2013-01-04

    The MuCap experiment at the Paul Scherrer Institute has measured the rate Λ(S) of muon capture from the singlet state of the muonic hydrogen atom to a precision of 1%. A muon beam was stopped in a time projection chamber filled with 10-bar, ultrapure hydrogen gas. Cylindrical wire chambers and a segmented scintillator barrel detected electrons from muon decay. Λ(S) is determined from the difference between the μ(-) disappearance rate in hydrogen and the free muon decay rate. The result is based on the analysis of 1.2 × 10(10) μ(-) decays, from which we extract the capture rate Λ(S) = (714.9 ± 5.4(stat) ± 5.1(syst)) s(-1) and derive the proton's pseudoscalar coupling g(P)(q(0)(2) = -0.88 m(μ)(2)) = 8.06 ± 0.55.

  9. Precise determination of deep trap signatures and their relative and absolute concentrations in semi-insulating GaAs

    NASA Astrophysics Data System (ADS)

    Pavlović, M.; Desnica, U. V.

    1998-08-01

    The new analytical method, simultaneous multiple peak analysis (SIMPA) which comprises simultaneous fitting of whole measured thermally stimulated current (TSC) spectra is presented. The procedure clearly resolves contributions from various overlapping TSC peaks, which results in precise determination of trap parameters (signature) for each trap. In combination with photocurrent temperature dependent measurements, IPC(T), which reflects free carrier lifetime temperature dependence, the estimates of relative and absolute trap concentrations were made as well. The advantage of the SIMPA method in comparison with the single peak approach was demonstrated and analyzed. The SIMPA method was applied to different semi-insulating (SI) GaAs samples, particularly to samples having very high and others having very low deep trap concentrations; and for both extremes excellent fits were achieved. The method also seems very promising for characterization of deep levels and other similar SI materials, like SI InP or SI CdTe.

  10. Precise Interferometric Phase Determination

    DTIC Science & Technology

    1988-08-30

    01731 J. Borovsky H. Gardiner S.P. Gary P. Kadish AUSTIN RESEARCH ASSOCIATES M. Pongratz 1901 Rutland Avenue D. Sappenfield Austin, TX 78758 G. Smith R...Aylesboro Road MISSION RESEARCH CORPORATION Pittsburg, PA 15217 One Tara Blvd., Ste. 302 N. Zabusky Nashua, NH 03062 R. Amstrong JAYCOR P.O. Box 85154

  11. Detection and Quantitation of Afucosylated N-Linked Oligosaccharides in Recombinant Monoclonal Antibodies Using Enzymatic Digestion and LC-MS

    NASA Astrophysics Data System (ADS)

    Du, Yi; May, Kimberly; Xu, Wei; Liu, Hongcheng

    2012-07-01

    The presence of N-linked oligosaccharides in the CH2 domain has a significant impact on the structure, stability, and biological functions of recombinant monoclonal antibodies. The impact is also highly dependent on the specific oligosaccharide structures. The absence of core-fucose has been demonstrated to result in increased binding affinity to Fcγ receptors and, thus, enhanced antibody-dependent cellular cytotoxicity (ADCC). Therefore, a method that can specifically determine the level of oligosaccharides without the core-fucose (afucosylation) is highly desired. In the current study, recombinant monoclonal antibodies and tryptic peptides from the antibodies were digested using endoglycosidases F2 and H, which cleaves the glycosidic bond between the two primary GlcNAc residues. As a result, various oligosaccharides of either complex type or high mannose type that are commonly observed for recombinant monoclonal antibodies are converted to either GlcNAc residue only or GlcNAc with the core-fucose. The level of GlcNAc represents the sum of all afucosylated oligosaccharides, whereas the level of GlcNAc with the core-fucose represents the sum of all fucosylated oligosaccharides. LC-MS analysis of the enzymatically digested antibodies after reduction provided a quick estimate of the levels of afucosylation. An accurate determination of the level of afucosylation was obtained by LC-MS analysis of glycopeptides after trypsin digestion.

  12. Precise Determination of Hypocenters and Focal Mechanisms of Volcanic Earthquakes by the Volcano Observation Network of NIED

    NASA Astrophysics Data System (ADS)

    Ueda, H.; Kohno, Y.; Nagai, M.; Miyagi, Y.; Fujita, E.; Kozono, T.; Tanada, T.

    2012-12-01

    Volcanic earthquakes are usually observed by a seismometer network on a volcano before and during eruptions, caused by crustal stress changes due to underground magma movements or an accumulation into a magma chamber. Precise hypocentral locations and focal mechanisms of the earthquakes provide information on the magmatic process and allow us to assess and predict the volcanic activity. However, focal mechanisms of volcanic earthquakes are not monitored except for relatively large earthquakes because of small size of volcanic earthquakes (M<3) and heterogeneity of volcanic structures. The obstacles also prevent automatic determination of hypocentral locations which are needed for short term eruption prediction. National Institute for Earth Science and Disaster Prevention (NIED) has been developing the volcano observation networks near the major active volcanos in Japan since 2009. The observation networks are equipped with short period seismometers and pendulum type tiltmeters at the bottom of borehole 200 m deep, and broad band seismometers and GPS antennas on the ground. We developed a monitoring technique for precise determination of hypocenters and focal mechanisms of volcanic earthquakes by using similarity of seismic wave forms and the high quality short period seismometer data of the volcano observation networks. Firstly, we extract earthquake groups which have similar seismic wave forms including P and S waves with correlation coefficient of more than 0.9 on more than three stations. Secondly, we display the wave forms with the similar phases in a row and stack them to reduce noises, and then precisely pick again the phases and first motion polarities of P waves. Thirdly, we relocate the hypocenters by Double-Difference method (Waldhauser and Ellsworth, 2000, BSSA) and estimate focal mechanisms by using P wave first motion polarity and S/P amplitude ratios (Hardebeck and Shearer, 2003, BSSA). We applied the technique to earthquake catalogs of Mt. Fuji and

  13. JASON-1 Precise Orbit Determination (POD) Through the Combination and Comparison of GPS, SLR, DORIS and Altimeter Crossover Data

    NASA Technical Reports Server (NTRS)

    Luthcke, Scott B.; Zelensky, N. P.; Rowlands, D. D.; Lemoine, F. G.; Chinn, D. S.; Williams, T. A.

    2002-01-01

    Jason-1, launched on December 7,2001, is continuing the time series of centimeter level ocean topography observations as the follow-on to the highly successful TOPEX/POSEIDON (T/P) radar altimeter satellite. The precision orbit determination (POD) is a critical component to meeting the ocean topography goals of the mission. T P has demonstrated that the time variation of ocean topography can be determined with an accuracy of a few centimeters, thanks to the availability of highly accurate orbits based primarily on SLR+DORIS tracking. The Jason-1 mission is intended to continue measurement of the ocean surface with the same, if not better accuracy. Fortunately, Jason- 1 POD can rely on four independent tracking data types available including near continuous tracking data from the dual frequency codeless BlackJack GPS receiver. Orbit solutions computed using individual and various combinations of GPS, SLR, DORIS and altimeter crossover data types have been determined from over 100 days of Jason-1 tracking data, The performance of the orbit solutions and tracking data has been evaluated. Orbit solution evaluation and comparison has provided insight into possible areas of refinement. Several aspects of the POD process are examined to obtain orbit improvements including measurement modeling, force modeling and solution strategy. The results of these analyses will be presented.

  14. JASON-1 Precise Orbit Determination (POD) Through the Combination and Comparison of GPS, SLR, DORIS and Altimeter Crossover Data

    NASA Technical Reports Server (NTRS)

    Luthcke, S. B.; Zelensky, N. P.; Lemoine, Frank G.; Chinn, D. S.; Williams, T. A.

    2002-01-01

    Jason-1, launched on December 7, 2001, is continuing the time series of centimeter level ocean topography observations as the follow-on to the highly successful TOPEX/POSEIDON (T/P) radar altimeter satellite. The precision orbit determination (POD) is a critical component to meeting the ocean topography goals of the mission. T/P has demonstrated that the time variation of ocean topography can be determined with an accuracy of a few centimeters, thanks to the availability of highly accurate orbits based primarily on SLR+DORIS tracking. The Jason-1 mission is intended to continue measurement of the ocean surface with the same, if not better accuracy. Fortunately, Jason-1 POD can rely on four independent tracking data types available including near continuous tracking data from the dual frequency codeless BlackJack GPS receiver. Orbit solutions computed using individual and various combinations of GPS, SLR, DORIS and altimeter crossover data types have been determined from over 100 days of Jason-1 tracking data. The performance of the orbit solutions and tracking data has been evaluated. Orbit solution evaluation and comparison has provided insight into possible areas of refinement. Several aspects of the POD process are examined to obtain orbit improvements including measurement modeling, force modeling and solution strategy. The results of these analyses will be presented.

  15. Precise determination of the ratio h/m u: a way to link microscopic mass to the new kilogram

    NASA Astrophysics Data System (ADS)

    Cladé, Pierre; Biraben, François; Julien, Lucile; Nez, François; Guellati-Khelifa, Saída

    2016-10-01

    The ratio h/{{m}\\text{u}} between the Planck constant and the unified atomic mass constant should have a special status in the framework of the future international system of units. Currently (before the redefinition), this ratio allowed the comparison between determinations of h (watt balance) and determinations of {{m}\\text{u}} (the XRCD method). In the future SI, as the Planck constant h will be fixed, the ratio h/{{m}\\text{u}} will ensure the realization of the new kilogram (quantum kilogram) at the atomic scale. Furthermore as the Avogadro constant will be fixed, the carbon molar mass M(12C), which will no longer be equal to 12~\\text{g}\\centerdot \\text{mo}{{\\text{l}}-1} , will be determined from m u. This ratio is also key data for the realization of the kilogram at the macroscopic scale using the XRCD method. In this paper we present the state of the art on experiments that provide the most precise value of the ratio h/{{m}\\text{u}} . We focus on the one that is based on the measurement of the atomic recoil due to the photon momentum.

  16. A modified time-of-flight method for precise determination of high speed ratios in molecular beams

    SciTech Connect

    Salvador Palau, A.; Eder, S. D. Kaltenbacher, T.; Samelin, B.; Holst, B.; Bracco, G.

    2016-02-15

    Time-of-flight (TOF) is a standard experimental technique for determining, among others, the speed ratio S (velocity spread) of a molecular beam. The speed ratio is a measure for the monochromaticity of the beam and an accurate determination of S is crucial for various applications, for example, for characterising chromatic aberrations in focussing experiments related to helium microscopy or for precise measurements of surface phonons and surface structures in molecular beam scattering experiments. For both of these applications, it is desirable to have as high a speed ratio as possible. Molecular beam TOF measurements are typically performed by chopping the beam using a rotating chopper with one or more slit openings. The TOF spectra are evaluated using a standard deconvolution method. However, for higher speed ratios, this method is very sensitive to errors related to the determination of the slit width and the beam diameter. The exact sensitivity depends on the beam diameter, the number of slits, the chopper radius, and the chopper rotation frequency. We present a modified method suitable for the evaluation of TOF measurements of high speed ratio beams. The modified method is based on a systematic variation of the chopper convolution parameters so that a set of independent measurements that can be fitted with an appropriate function are obtained. We show that with this modified method, it is possible to reduce the error by typically one order of magnitude compared to the standard method.

  17. A modified time-of-flight method for precise determination of high speed ratios in molecular beams

    NASA Astrophysics Data System (ADS)

    Salvador Palau, A.; Eder, S. D.; Kaltenbacher, T.; Samelin, B.; Bracco, G.; Holst, B.

    2016-02-01

    Time-of-flight (TOF) is a standard experimental technique for determining, among others, the speed ratio S (velocity spread) of a molecular beam. The speed ratio is a measure for the monochromaticity of the beam and an accurate determination of S is crucial for various applications, for example, for characterising chromatic aberrations in focussing experiments related to helium microscopy or for precise measurements of surface phonons and surface structures in molecular beam scattering experiments. For both of these applications, it is desirable to have as high a speed ratio as possible. Molecular beam TOF measurements are typically performed by chopping the beam using a rotating chopper with one or more slit openings. The TOF spectra are evaluated using a standard deconvolution method. However, for higher speed ratios, this method is very sensitive to errors related to the determination of the slit width and the beam diameter. The exact sensitivity depends on the beam diameter, the number of slits, the chopper radius, and the chopper rotation frequency. We present a modified method suitable for the evaluation of TOF measurements of high speed ratio beams. The modified method is based on a systematic variation of the chopper convolution parameters so that a set of independent measurements that can be fitted with an appropriate function are obtained. We show that with this modified method, it is possible to reduce the error by typically one order of magnitude compared to the standard method.

  18. Variations in prebiotic oligosaccharide fermentation by intestinal lactic acid bacteria.

    PubMed

    Endo, Akihito; Nakamura, Saki; Konishi, Kenta; Nakagawa, Junichi; Tochio, Takumi

    2016-01-01

    Prebiotic oligosaccharides confer health benefits on the host by modulating the gut microbiota. Intestinal lactic acid bacteria (LAB) are potential targets of prebiotics; however, the metabolism of oligosaccharides by LAB has not been fully characterized. Here, we studied the metabolism of eight oligosaccharides by 19 strains of intestinal LAB. Among the eight oligosaccharides used, 1-kestose, lactosucrose and galactooligosaccharides (GOSs) led to the greatest increases in the numbers of the strains tested. However, mono- and disaccharides accounted for more than half of the GOSs used, and several strains only metabolized the mono- and di-saccharides in GOSs. End product profiles indicated that the amounts of lactate produced were generally consistent with the bacterial growth recorded. Oligosaccharide profiling revealed the interesting metabolic manner in Lactobacillus paracasei strains, which metabolized all oligosaccharides, but left sucrose when cultured with fructooligosaccharides. The present study clearly indicated that the prebiotic potential of each oligosaccharide differs.

  19. The Precise Determination of Cd Isotope Ratio in Geological Samples by MC-ICP-MS with Ion Exchange Separation

    NASA Astrophysics Data System (ADS)

    Du, C.; Hu, S.; Wang, D.; Jin, L.; Guo, W.

    2014-12-01

    Cadmium (Cd) is a trace element which occurs at μg g-1 level abundances in the crust. Cd isotopes have great prospects in the study of the cosmogony, the trace of anthropogenic sources, the micronutrient cycling and the ocean productivity. This study develops an optimized technique for the precise and accurate determination of Cd isotopic compositions. Cd was separated from the matrix by elution with AG-MP-1 anionic exchange chromatographic resin. The matrix elements (K, Na, Ca, Al, Fe, and Mg etc.), polyatomic interfered elements (Ge, Ga, Zr, Nb, Ru, and Mo), and isobaric interfered elements (In, Pd and most of Sn) were eluted using HCl with gradient descent concentrations (2, 0.3, 0.06, 0.012 and 0.0012 mol L-1). The same elution procedure was repeated to eliminate the residuel Sn (Sn/Cd < 0.018). The collected Cd was analyzed using MC-ICP-MS, in which the instrumental mass fractionation was controlled by a "sample-standard bracketing" technique. The recovery of Cd larger than 96.85%, and the δ114/110Cd are in the range of -1.43~+0.20‰ for ten geological reference materials (GSD-3a, GSD-5a, GSD-7a, GSD-6, GSD-9, GSD-10, GSD-11, GSD-12, GSD-23, and GSS-1). The δ114/110Cd obtained for GSS-1 soil sample relative to the NIST SRM 3108 Cd solution was 0.20, which was coherent with the literature values (0.08±0.23). This method had a precision of 0.001~0.002% (RSD), an error range of 0.06~0.14 (δ114/110Cd, 2σ), and a long-term reproducibility of 0.12 (δ114/110Cd, 2σ).

  20. High-precision (p,t) reaction to determine {sup 25}Al(p,{gamma}){sup 26}Si reaction rates

    SciTech Connect

    Matic, A.; Berg, A. M. van den; Harakeh, M. N.; Woertche, H. J.; Berg, G. P. A.; Couder, M.; Goerres, J.; LeBlanc, P.; O'Brien, S.; Wiescher, M.; Fujita, K.; Hatanaka, K.; Sakemi, Y.; Shimizu, Y.; Tameshige, Y.; Tamii, A.; Yosoi, M.; Adachi, T.; Fujita, Y.; Shimbara, Y.

    2010-08-15

    Since the identification of ongoing {sup 26}Al production in the universe, the reaction sequence {sup 24}Mg(p,{gamma}){sup 25}Al({beta}{sup +{nu}}){sup 25}Mg(p,{gamma}){sup 26}Al has been studied intensively. At temperatures where the radiative capture on {sup 25}Al (t{sub 1/2}=7.2 s) becomes faster than the {beta}{sup +} decay, the production of {sup 26}Al can be reduced due to the depletion of {sup 25}Al. To determine the resonances relevant for the {sup 25}Al(p,{gamma}){sup 26}Si bypass reaction, we measured the {sup 28}Si(p,t){sup 26}Si reaction with high-energy precision using the Grand Raiden spectrometer at the Research Center for Nuclear Physics, Osaka. Several new energy levels were found above the p threshold and for known states excitation energies were determined with smaller uncertainties. The calculated stellar rates of the bypass reaction agree well with previous results, suggesting that these rates are well established.

  1. Precise Orbit Determination for GEOSAT Follow-On Using Satellite Laser Ranging Data and Intermission Altimeter Crossovers

    NASA Technical Reports Server (NTRS)

    Lemoine, Frank G.; Rowlands, David D.; Luthcke, Scott B.; Zelensky, Nikita P.; Chinn, Douglas S.; Pavlis, Despina E.; Marr, Gregory

    2001-01-01

    The US Navy's GEOSAT Follow-On Spacecraft was launched on February 10, 1998 with the primary objective of the mission to map the oceans using a radar altimeter. Following an extensive set of calibration campaigns in 1999 and 2000, the US Navy formally accepted delivery of the satellite on November 29, 2000. Satellite laser ranging (SLR) and Doppler (Tranet-style) beacons track the spacecraft. Although limited amounts of GPS data were obtained, the primary mode of tracking remains satellite laser ranging. The GFO altimeter measurements are highly precise, with orbit error the largest component in the error budget. We have tuned the non-conservative force model for GFO and the gravity model using SLR, Doppler and altimeter crossover data sampled over one year. Gravity covariance projections to 70x70 show the radial orbit error on GEOSAT was reduced from 2.6 cm in EGM96 to 1.3 cm with the addition of SLR, GFO/GFO and TOPEX/GFO crossover data. Evaluation of the gravity fields using SLR and crossover data support the covariance projections and also show a dramatic reduction in geographically-correlated error for the tuned fields. In this paper, we report on progress in orbit determination for GFO using GFO/GFO and TOPEX/GFO altimeter crossovers. We will discuss improvements in satellite force modeling and orbit determination strategy, which allows reduction in GFO radial orbit error from 10-15 cm to better than 5 cm.

  2. Synthesis of high-mannose oligosaccharide analogues through click chemistry: true functional mimics of their natural counterparts against lectins?

    PubMed

    François-Heude, Marc; Méndez-Ardoy, Alejandro; Cendret, Virginie; Lafite, Pierre; Daniellou, Richard; Ortiz Mellet, Carmen; García Fernández, José M; Moreau, Vincent; Djedaïni-Pilard, Florence

    2015-01-26

    Terminal "high-mannose oligosaccharides" are involved in a broad range of biological and pathological processes, from sperm-egg fusion to influenza and human immunodeficiency virus infections. In spite of many efforts, their synthesis continues to be very challenging and actually represents a major bottleneck in the field. Whereas multivalent presentation of mannopyranosyl motifs onto a variety of scaffolds has proven to be a successful way to interfere in recognition processes involving high-mannose oligosaccharides, such constructs fail at reproducing the subtle differences in affinity towards the variety of protein receptors (lectins) and antibodies susceptible to binding to the natural ligands. Here we report a family of functional high-mannose oligosaccharide mimics that reproduce not only the terminal mannopyranosyl display, but also the core structure and the branching pattern, by replacing some inner mannopyranosyl units with triazole rings. Such molecular design can be implemented by exploiting "click" ligation strategies, resulting in a substantial reduction of synthetic cost. The binding affinities of the new "click" high-mannose oligosaccharide mimics towards two mannose specific lectins, namely the plant lectin concanavalin A (ConA) and the human macrophage mannose receptor (rhMMR), have been studied by enzyme-linked lectin assays and found to follow identical trends to those observed for the natural oligosaccharide counterparts. Calorimetric determinations against ConA, and X-ray structural data support the conclusion that these compounds are not just another family of multivalent mannosides, but real "structural mimics" of the high-mannose oligosaccharides.

  3. Structural Characterization of Neutral Oligosaccharides by Laser-Enhanced In-Source Decay of MALDI-FTICR MS

    NASA Astrophysics Data System (ADS)

    Yang, Hongmei; Yu, Yingning; Song, Fengrui; Liu, Shuying

    2011-05-01

    MALDI in-source decay (ISD) technique described to date has proven to be a convenient and rapid method for sequencing purified peptides and proteins. However, the general ISD still can not produce adequate fragments for the detailed structural elucidation of oligosaccharides. In this study, an efficient and practical method termed the laser-enhanced ISD (LEISD) technique of MALDI-FTICR MS allows highly reliable and abundant fragmentation of the neutral oligosaccharides, which was attributed to the ultrahigh irradiation laser of mJ level. The yield of ISD fragmentation was evaluated under different laser powers for 7 neutral oligosaccharides using DHB as matrix. Better quality ISD spectra including fragment ions in low-mass region were obtained at higher laser power. Results from the LEISD of oligosaccharides demonstrated that a significantly better signal-to-noise ratio (S/N) and more structural information could be obtained in comparison to the conventional CID. It was also suggested that the valuable A ions derived from cross-ring cleavage of the linear oligosaccharides allowed the distinction among α(1 → 4)-, α(1 → 6)-, β(1 → 4)-, and β(1 → 3)-linked isobaric structures according to fragment types and intensities. In addition, ideal fragmentation ions observed by LEISD method facilitated the determination of the sequences and branched points of complex oligosaccharides from human milk.

  4. Comparison of TOPEX/Poseidon orbit determination solutions obtained by the Goddard Space Flight Center Flight Dynamics Division and Precision Orbit Determination Teams

    NASA Astrophysics Data System (ADS)

    Doll, C.; Mistretta, G.; Hart, R.; Oza, D.; Cox, C.; Nemesure, M.; Bolvin, D.; Samii, Mina V.

    Orbit determination results are obtained by the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) using the Goddard Trajectory Determination System (GTDS) and a real-time extended Kalman filter estimation system to process Tracking Data and Relay Satellite (TDRS) System (TDRSS) measurements in support of the Ocean Topography Experiment (TOPEX)/Poseidon spacecraft navigation and health and safety operations. GTDS is the operational orbit determination system used by the FDD, and the extended Kalman fliter was implemented in an analysis prototype system, the Real-Time Orbit Determination System/Enhanced (RTOD/E). The Precision Orbit Determination (POD) team within the GSFC Space Geodesy Branch generates an independent set of high-accuracy trajectories to support the TOPEX/Poseidon scientific data. These latter solutions use the Geodynamics (GEODYN) orbit determination system with laser ranging tracking data. The TOPEX/Poseidon trajectories were estimated for the October 22 - November 1, 1992, timeframe, for which the latest preliminary POD results were available. Independent assessments were made of the consistencies of solutions produced by the batch and sequential methods. The batch cases were assessed using overlap comparisons, while the sequential cases were assessed with covariances and the first measurement residuals. The batch least-squares and forward-filtered RTOD/E orbit solutions were compared with the definitive POD orbit solutions. The solution differences were generally less than 10 meters (m) for the batch least squares and less than 18 m for the sequential estimation solutions. The differences among the POD, GTDS, and RTOD/E solutions can be traced to differences in modeling and tracking data types, which are being analyzed in detail.

  5. LC-MS/MS analysis of permethylated free oligosaccharides and N-glycans derived from human, bovine, and goat milk samples.

    PubMed

    Dong, Xue; Zhou, Shiyue; Mechref, Yehia

    2016-06-01

    Oligosaccharides in milk not only provide nutrition to the infants but also have significant immune biofunctions such as inhibition of pathogen binding to the host cell. The main component in milk oligosaccharides is free oligosaccharides. Since the proteins in milk are highly glycosylated, N-glycans in milk also play an import role. In this study, we investigated the permethylated free oligosaccharides and N-glycans extracted from bovine, goat, and human milks using LC-MS/MS. Quantitation profiles of free oligosaccharides and N-glycans were reported. The number of free oligosaccharides observed in bovine, goat, and human milk samples (without isomeric consideration) were 11, 8, and 11, respectively. Human milk had more complex free oligosaccharides structures than the other two milk samples. Totally 58, 21, and 43 N-glycan structures (without isomeric consideration) were associated with whey proteins extracted from bovine, goat, and human milk samples, respectively. Bovine milk free oligosaccharides and N-glycans from whey proteins were highly sialylated and to a lesser extend fucosylated. Goat and human milk free oligosaccharides and N-glycans from whey proteins were both highly fucosylated. Also, the isomeric glycans in milk samples were determined by porous graphitic carbon LC at elevated temperatures. For example, separation of human milk free oligosaccharide Gal-GlcNAc-(Fuc)-Gal-Glc and Gal-GlcNAc-Gal-Glc-Fuc isomers was achieved using porous graphitic carbon column. Permethylation of the glycan structures facilitated the interpretation of MS/MS. For example, internal cleavage and glycosidic bond cleavage are readily distinguished in the tandem mass spectra of permethylated glycans. This feature resulted in the identification of several isomers.

  6. Bracketing method with certified reference materials for high precision and accuracy determination of trace cadmium in drinking water by Inductively Coupled Plasma - Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Ketrin, Rosi; Handayani, Eka Mardika; Komalasari, Isna

    2017-01-01

    Two significant parameters to evaluate the measurement results are known as precision and accuracy. Both are associated with indeterminate and determinate error, respectively, that normally happen in such spectrometric measurement method as Inductively Coupled Plasma - Mass Spectrometry (ICP-MS). These errors must be eliminated or suppressed to get high precision and accuracy of the method. Decreasing the errors thus increasing the precision and accuracy of the method. In this study, bracketing method using two-point standard calibration was proposed in order to suppress the indeterminate error caused by instrumental drift thus increasing the result precision, and applied for measuring cadmium in drinking water samples. Certified reference material of ERM CA011b-Hard drinking water UK-metals was used to know the determinate error or measurement bias. When bias is obtained, some corrections are needed to get the accurate measurement result. The result was compared to that by external calibration method.

  7. Accuracy and precision of hind limb foot contact timings of horses determined using a pelvis-mounted inertial measurement unit.

    PubMed

    Starke, Sandra D; Witte, Thomas H; May, Stephen A; Pfau, Thilo

    2012-05-11

    Gait analysis using small sensor units is becoming increasingly popular in the clinical context. In order to segment continuous movement from a defined point of the stride cycle, knowledge about footfall timings is essential. We evaluated the accuracy and precision of foot contact timings of a defined limb determined using an inertial sensor mounted on the pelvis of ten horses during walk and trot at different speeds and in different directions. Foot contact was estimated from vertical velocity events occurring before maximum sensor roll towards the contralateral limb. Foot contact timings matched data from a synchronised hoof mounted accelerometer well when velocity minimum was used for walk (mean (SD) difference of 15 (18)ms across horses) and velocity zero-crossing for trot (mean (SD) difference from -4 (14) to 12 (7)ms depending on the condition). The stride segmentation method also remained robust when applied to movement data of hind limb lame horses. In future, this method may find application in segmenting overground sensor data of various species.

  8. Precise orbit and attitude determination using redundant low-cost single-frequency GNSS receivers on a CubeSat

    NASA Astrophysics Data System (ADS)

    Willi, Daniel; Fisler, Michael; Hollenstein, Christine; Männel, Benjamin; Meindl, Michael; Xu, Hui; Rothacher, Markus

    2016-07-01

    CubETH is a technology demonstration mission aimed at using low-cost commercial-off-the-shelf GNSS receivers for space applications. Precise orbit and attitude determination, on-board as well as in post-processing, are the main mission goals. The one unit cube-satellite is equipped with five GNSS antennas, each of them connected to two u-blox multi-GNSS receivers. The position estimation on the satellite is based on the receiver navigation solution. We show that (1) the proper correction of the ionospheric path delay and (2) the position propagation in the Kalman filter are of uppermost importance. Based on available data from the GRACE and GOCE missions, we show how an adapted Klobuchar model leads to a better estimation of the path delay in low Earth orbits. Based on recent signal-simulator tests, we illustrate how the linear propagation in the receiver Kalman filter leads to systematic errors and exhibit a method for improvement.

  9. Precise Determination of the Zero-Gravity Surface Figure of a Mirror without Gravity-Sag Modeling

    NASA Technical Reports Server (NTRS)

    Bloemhof, Eric E.; Lam, Jonathan C.; Feria, V. Alfonso; Chang, Zensheu

    2007-01-01

    The zero-gravity surface figure of optics used in spaceborne astronomical instruments must be known to high accuracy, but earthbound metrology is typically corrupted by gravity sag. Generally, inference of the zero-gravity surface figure from a measurement made under normal gravity requires finite-element analysis (FEA), and for accurate results the mount forces must be well characterized. We describe how to infer the zero-gravity surface figure very precisely using the alternative classical technique of averaging pairs of measurements made with the direction of gravity reversed. We show that mount forces as well as gravity must be reversed between the two measurements and discuss how the St. Venant principle determines when a reversed mount force may be considered to be applied at the same place in the two orientations. Our approach requires no finite-element modeling and no detailed knowledge of mount forces other than the fact that they reverse and are applied at the same point in each orientation. If mount schemes are suitably chosen, zero-gravity optical surfaces may be inferred much more simply and more accurately than with FEA.

  10. Determination of volume and surface scattering from saline ice using ice sheets with precisely controlled roughness parameters

    SciTech Connect

    Bredow, J.W.; Porco, R.L.; Fung, A.K.; Tjuatja, S.; Jezek, K.C.; Gogineni, S.; Gow, A.J.

    1995-09-01

    Experiments were performed at the US Army Cold Regions Research and Engineering Laboratory (CRREL) in Hanover, NH, to precisely determine the relative contributions of surface and volume scattering from saline ice that has well-known surface roughness characteristics. The ice growth phase of the experiment made use of two 6-ft diameter tanks and a 6-ft diameter mold with known roughness statistical parameters of rms height = 0.25 cm and Gaussian correlation (correlation length = 2.0 cm). One tank was used for growing a moderately thick saline ice sheet with very smooth surface, and the other was used for growing a thin layer of freshwater ice over the surface mold. The latter resulted in a layer with one statistically known rough boundary and one smooth boundary. Wide-bandwidth, multiple incidence angle backscattering measurements were performed, first on the bare saline ice sheet and then on the same sheet after the thin freshwater ice sheet was placed on top of it. Results indicate that the surface scattering dominates over saline ice volume scattering at all frequencies for low incidence angles for both the very smooth and Gaussian rough surfaces. The significance of volume scattering depends strongly on angle of incidence, frequency, volume scattering albedo, surface roughness, and surface correlation function.

  11. Oligosaccharide formation during commercial pear juice processing.

    PubMed

    Willems, Jamie L; Low, Nicholas H

    2016-08-01

    The effect of enzyme treatment and processing on the oligosaccharide profile of commercial pear juice samples was examined by high performance anion exchange chromatography with pulsed amperometric detection and capillary gas chromatography with flame ionization detection. Industrial samples representing the major stages of processing produced with various commercial enzyme preparations were studied. Through the use of commercially available standards and laboratory scale enzymatic hydrolysis of pectin, starch and xyloglucan; galacturonic acid oligomers, glucose oligomers (e.g., maltose and cellotriose) and isoprimeverose were identified as being formed during pear juice production. It was found that the majority of polysaccharide hydrolysis and oligosaccharide formation occurred during enzymatic treatment at the pear mashing stage and that the remaining processing steps had minimal impact on the carbohydrate-based chromatographic profile of pear juice. Also, all commercial enzyme preparations and conditions (time and temperature) studied produced similar carbohydrate-based chromatographic profiles.

  12. Determining storm sampling requirements for improving precision of annual load estimates of nutrients from a small forested watershed.

    PubMed

    Ide, Jun'ichiro; Chiwa, Masaaki; Higashi, Naoko; Maruno, Ryoko; Mori, Yasushi; Otsuki, Kyoichi

    2012-08-01

    This study sought to determine the lowest number of storm events required for adequate estimation of annual nutrient loads from a forested watershed using the regression equation between cumulative load (∑L) and cumulative stream discharge (∑Q). Hydrological surveys were conducted for 4 years, and stream water was sampled sequentially at 15-60-min intervals during 24 h in 20 events, as well as weekly in a small forested watershed. The bootstrap sampling technique was used to determine the regression (∑L-∑Q) equations of dissolved nitrogen (DN) and phosphorus (DP), particulate nitrogen (PN) and phosphorus (PP), dissolved inorganic nitrogen (DIN), and suspended solid (SS) for each dataset of ∑L and ∑Q. For dissolved nutrients (DN, DP, DIN), the coefficient of variance (CV) in 100 replicates of 4-year average annual load estimates was below 20% with datasets composed of five storm events. For particulate nutrients (PN, PP, SS), the CV exceeded 20%, even with datasets composed of more than ten storm events. The differences in the number of storm events required for precise load estimates between dissolved and particulate nutrients were attributed to the goodness of fit of the ∑L-∑Q equations. Bootstrap simulation based on flow-stratified sampling resulted in fewer storm events than the simulation based on random sampling and showed that only three storm events were required to give a CV below 20% for dissolved nutrients. These results indicate that a sampling design considering discharge levels reduces the frequency of laborious chemical analyses of water samples required throughout the year.

  13. The Application of GIM in Precise Orbit Determination for LEO Satellites with Single-Frequency GPS Measurements

    NASA Astrophysics Data System (ADS)

    Peng, Dong-ju; Wu, Bin

    2012-10-01

    With the precise GPS ephemeris and clock error available, the iono- spheric delay is left as the dominant error source in the single-frequency GPS data. Thus, the removal of ionospheric effects is a ma jor prerequisite for an improved orbit reconstruction of LEO satellites based on the single-frequency GPS data. In this paper, the use of Global Ionospheric Maps (GIM) in kine- matic and dynamic orbit determinations for LEO satellites with single-frequency GPS pseudorange measurements is discussed first, and then, estimating the iono- spheric scale factor to remove the ionospheric effects from the C/A-code pseu- dorange measurements for both kinematic and dynamic orbit determinations is addressed. As it is known that the ionospheric delay of space-borne GPS sig- nals is strongly dependent on the orbit altitudes of LEO satellites, we select the real C/A-code pseudorange measurement data of the CHAMP, GRACE, TerraSAR-X and SAC-C satellites with altitudes between 300 km and 800 km as sample data in this paper. It is demonstrated that the approach to eliminating ionospheric effects in C/A-code pseudorange measurements by estimating the ionospheric scale factor is highly effective. Employing this approach, the accu- racy of both kinematic and dynamic orbits can be improved notably. Among those five LEO satellites, CHAMP with the lowest orbit altitude has the most remarkable improvements in orbit accuracy, which are 55.6% and 47.6% for kine- matic and dynamic orbits, respectively. SAC-C with the highest orbit altitude has the least improvements in orbit accuracy accordingly, which are 47.8% and 38.2%, respectively.

  14. Divergent Synthesis of Heparan Sulfate Oligosaccharides

    PubMed Central

    2015-01-01

    Heparan sulfates are implicated in a wide range of biological processes. A major challenge in deciphering their structure and activity relationship is the synthetic difficulties to access diverse heparan sulfate oligosaccharides with well-defined sulfation patterns. In order to expedite the synthesis, a divergent synthetic strategy was developed. By integrating chemical synthesis and two types of O-sulfo transferases, seven different hexasaccharides were obtained from a single hexasaccharide precursor. This approach combined the flexibility of chemical synthesis with the selectivity of enzyme-catalyzed sulfations, thus simplifying the overall synthetic operations. In an attempt to establish structure activity relationships of heparan sulfate binding with its receptor, the synthesized oligosaccharides were incorporated onto a glycan microarray, and their bindings with a growth factor FGF-2 were examined. The unique combination of chemical and enzymatic approaches expanded the capability of oligosaccharide synthesis. In addition, the well-defined heparan sulfate structures helped shine light on the fine substrate specificities of biosynthetic enzymes and confirm the potential sequence of enzymatic reactions in biosynthesis. PMID:26574650

  15. Effect of fructo-oligosaccharide and isomalto-oligosaccharide addition on baking quality of frozen dough.

    PubMed

    Park, Eun Young; Jang, Sung-Bum; Lim, Seung-Taik

    2016-12-15

    The baking quality of frozen doughs containing different levels of fructo-oligosaccharides (FO) or isomalto-oligosaccharides (IMO) (3-9%, w/w flour), and stored for 0-8weeks at -18°C, was examined. The addition of FO or IMO increased the proof volume of the dough and the loaf volume of bread prepared from frozen dough. A 6% addition of FO or IMO was optimum, giving the highest proof volume and bread loaf volume, but a higher concentration than 6% induced low baking quality including lower proof volume and bread loaf volume. The bread crumb was moister and softer after the addition of FO or IMO before, and even after, frozen storage. Darker crumb colour was observed in the bread after the addition of FO or IMO. The oligosaccharides added to the frozen dough were effective in improving the quality of bread made from frozen dough, except for resulting in a darker bread crumb.

  16. In Vitro Fermentation of Porcine Milk Oligosaccharides and Galacto-oligosaccharides Using Piglet Fecal Inoculum.

    PubMed

    Difilippo, Elisabetta; Pan, Feipeng; Logtenberg, Madelon; Willems, Rianne H A M; Braber, Saskia; Fink-Gremmels, Johanna; Schols, Henk A; Gruppen, Harry

    2016-03-16

    In this study, the in vitro fermentation by piglet fecal inoculum of galacto-oligosaccharides (GOS) and porcine milk oligosaccharides (PMOs) was investigated to identify possible preferences for individual oligosaccharide structures by piglet microbiota. First, acidic PMOs and GOS with degrees of polymerization 4-7 were depleted within 12 h of fermentation, whereas fucosylated and phosphorylated PMOs were partially resistant to fermentation. GOS structures containing β1-3 and β1-2 linkages were preferably fermented over GOS containing β1-4 and β1-6 linkages. Upon in vitro fermentation, acetate and butyrate were produced as the main organic acids. GOS fermentation by piglet inoculum showed a unique fermentation pattern with respect to preference of GOS size and organic acids production.

  17. Structure analysis and laxative effects of oligosaccharides isolated from bananas.

    PubMed

    Wang, Juan; Huang, Hui Hua; Cheng, Yan Feng; Yang, Gong Ming

    2012-10-01

    Banana oligosaccharides (BOS) were extracted with water, and then separated and purified using column chromatography. Gel penetration chromatography was used to determine the molecular weights. Thin layer chromatogram and capillary electrophoresis were employed to analyze the monosaccharide composition. The indican bond and structure of the BOS molecule were determined using Fourier transform infrared spectroscopy and nuclear magnetic resonance. Results showed that BOS were probably composed of eight β-D-pyran glucose units linked with 1→6 indican bonds. The laxative effects of BOS were investigated in mice using the method described in "Handbook of Technical Standards for Testing and Assessment of Health Food in China." The length of the small intestine over which a carbon suspension solution advanced in mice treated with low-, middle-, and high-dose BOS was significantly greater than that in the model group, suggesting that BOS are effective in accelerating the movement of the small intestine.

  18. Three Decades of Precision Orbit Determination Progress, Achievements, Future Challenges and its Vital Contribution to Oceanography and Climate Research

    NASA Technical Reports Server (NTRS)

    Luthcke, Scott; Rowlands, David; Lemoine, Frank; Zelensky, Nikita; Beckley, Brian; Klosko, Steve; Chinn, Doug

    2006-01-01

    Although satellite altimetry has been around for thirty years, the last fifteen beginning with the launch of TOPEX/Poseidon (TP) have yielded an abundance of significant results including: monitoring of ENS0 events, detection of internal tides, determination of accurate global tides, unambiguous delineation of Rossby waves and their propagation characteristics, accurate determination of geostrophic currents, and a multi-decadal time series of mean sea level trend and dynamic ocean topography variability. While the high level of accuracy being achieved is a result of both instrument maturity and the quality of models and correction algorithms applied to the data, improving the quality of the Climate Data Records produced from altimetry is highly dependent on concurrent progress being made in fields such as orbit determination. The precision orbits form the reference frame from which the radar altimeter observations are made. Therefore, the accuracy of the altimetric mapping is limited to a great extent by the accuracy to which a satellite orbit can be computed. The TP mission represents the first time that the radial component of an altimeter orbit was routinely computed with an accuracy of 2-cm. Recently it has been demonstrated that it is possible to compute the radial component of Jason orbits with an accuracy of better than 1-cm. Additionally, still further improvements in TP orbits are being achieved with new techniques and algorithms largely developed from combined Jason and TP data analysis. While these recent POD achievements are impressive, the new accuracies are now revealing subtle systematic orbit error that manifest as both intra and inter annual ocean topography errors. Additionally the construction of inter-decadal time series of climate data records requires the removal of systematic differences across multiple missions. Current and future efforts must focus on the understanding and reduction of these errors in order to generate a complete and

  19. The application of the ITRF2014 Product Center solutions with respect to Altimeter Satellite Precise Orbit Determination

    NASA Astrophysics Data System (ADS)

    Lemoine, Frank G.; Zelensky, Nikita P.; Couhert, Alexandre; Jalabert, Eva; Chinn, Douglas S.

    2016-04-01

    The IERS product centers, IGN, DGFI, and JPL, have prepared new solution realizations of the International Terrestrial Reference Frame (ITRF), based on the analysis and the combination SINEX solutions submitted by the individual geodetic techniques: Satellite Laser Ranging (SLR), Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS), Very Long Baseline Interferometry (VLBI), and Global Navigation Satellite Systems (GNSS). We evaluate these solutions with respect to their orbit determination performance, including RMS of fit, and other orbit metrics, including altimeter crossovers, focusing on the altimeter satellites, in particular TOPEX/Poseidon, Jason-1, and Jason-2, but also Cryosat-2 and Envisat. We also evaluate the POD performance using the Jason-2 JPL/reduced-dynamic orbits as a reference. We have conducted a preliminary evaluation of the new solutions so far released, ITRF2014P (IGN), and DTRF2014 (DGFI) with respect to the Jason-2 satellite, and find a significant improvement in the DORIS satellite RMS of fit for DORIS-only orbit computations. Over 260 orbit cycles (July 2008 to August 2015) the RMS of fit improves from 0.3667 mm/s for DPOD2008 to 0.3646 and 0.3645 mm/s for the two new ITRF2014 realizations. The following stations show improvements in RMS of fit of more than 0.02 mm/s, which is significant for DORIS data: KRUB/KRWB (Kourou), CIDB (Cibinong), JIUB (Jiufeng), YEMB (Yellowknife), MATB (Marion Island), FUTB (Futuna), and ARFB (Arequipa). In this paper we also focus on the SLR performance, and we evaluate how the new ITRF2014 reference frame realization can be integrated into the next generation of precision orbit improvements for the Jason series of satellites.

  20. Structure of a sialo-oligosaccharide from glycophorin in carp red blood cell membranes.

    PubMed

    Aoki, Takahiko; Chimura, Kenji; Sugiura, Hikaru; Mizuno, Yasuko

    2014-11-13

    We isolated a high-purity carp glycophorin from carp erythrocyte membranes and prepared the oligosaccharide fraction from glycophorin by β-elimination [1]. The oligosaccharide fraction was separated into two components (P-1 and P-2) using a Glyco-Pak DEAE column. These O-linked oligosaccharides (P-1 and P-2) were composed of glucose, galactose, fucose, N-acetylgalactosamine and N-glycolylneuraminic acid (NeuGc). The P-1 and P-2 contained one and two NeuGc residues, respectively, and the P-1 exhibited bacteriostatic activity [1]. Using NMR and GC-MS, we determined that the structure of the bacteriostatic P-1 was NeuGcα2→6 (Fucα1→4) (Glcα1→3) Galβ1→4GalNAc-ol. This O-linked oligosaccharide was unique for a vertebrate with respect to the hexosamine and hexose linkages and its non-chain structure.

  1. Consumption of human milk oligosaccharides by gut-related microbes.

    PubMed

    Marcobal, Angela; Barboza, Mariana; Froehlich, John W; Block, David E; German, J Bruce; Lebrilla, Carlito B; Mills, David A

    2010-05-12

    Human milk contains large amounts of complex oligosaccharides that putatively modulate the intestinal microbiota of breast-fed infants by acting as decoy binding sites for pathogens and as prebiotics for enrichment of beneficial bacteria. Several bifidobacterial species have been shown to grow well on human milk oligosaccharides. However, few data exist on other bacterial species. This work examined 16 bacterial strains belonging to 10 different genera for growth on human milk oligosaccharides. For this propose, a chemically defined medium, ZMB1, was used, which allows vigorous growth of a number of gut-related microorganisms in a fashion similar to complex media. Interestingly, Bifidobacterium longum subsp. infantis, Bacteroides fragilis , and Bacteroides vulgatus strains were able to metabolize milk oligosaccharides with high efficiency, whereas Enterococcus , Streptococcus , Veillonella , Eubacterium , Clostridium , and Escherichia coli strains grew less well or not at all. Mass spectrometry-based glycoprofiling of the oligosaccharide consumption behavior revealed a specific preference for fucosylated oligosaccharides by Bi. longum subsp. infantis and Ba. vulgatus. This work expands the current knowledge of human milk oligosaccharide consumption by gut microbes, revealing bacteroides as avid consumers of this substrate. These results provide insight on how human milk oligosaccharides shape the infant intestinal microbiota.

  2. Consumption of Human Milk Oligosaccharides by Gut-related Microbes

    PubMed Central

    Marcobal, Angela; Barboza, Mariana; Froehlich, John W.; Block, David E.; German, J. Bruce; Lebrilla, Carlito B.; Mills, David A.

    2010-01-01

    Human milk contains large amounts of complex oligosaccharides that putatively modulate the intestinal microbiota of breast-fed infants by acting as decoy binding sites for pathogens and as prebiotics for enrichment of beneficial bacteria. Several bifidobacterial species have been shown to grow well on human milk oligosaccharides. However, little data exists on other bacterial species. In this work we examined 16 bacterial strains belonging to 10 different genera for growth on human milk oligosaccharides. For this propose, we used a chemically-defined medium, ZMB1, which allows vigorous growth of a number gut–related microorganisms in a fashion similar to complex media. Interestingly, Bifidobacterium longum subsp. infantis, Bacteroides fragilis and Bacteroides vulgatus strains were able to metabolize milk oligosaccharides with high efficiency, while Enterococcus, Streptococcus, Veillonella, Eubacterium, Clostridium, and Escherichia coli strains grew less well or not at all. Mass spectrometry-based glycoprofiling of the oligosaccharide consumption behavior revealed a specific preference for fucosylated oligosaccharides by Bifidobacterium longum subsp. infantis and Bacteroides vulgatus. This work expands the current knowledge of human milk oligosaccharides consumption by gut microbes, revealing bacteroides as avid consumer of this substrate. These results provide insight on how human milk oligosaccharides shape the infant intestinal microbiota. PMID:20394371

  3. 40 CFR 80.584 - What are the precision and accuracy criteria for approval of test methods for determining the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... diesel fuel, and ECA marine fuel? 80.584 Section 80.584 Protection of Environment ENVIRONMENTAL... Diesel Fuel; Nonroad, Locomotive, and Marine Diesel Fuel; and ECA Marine Fuel Sampling and Testing § 80... sulfur content of motor vehicle diesel fuel, NRLM diesel fuel, and ECA marine fuel? (a) Precision....

  4. Improved thickness estimation of liquid water using Kramers-Kronig relations for determination of precise optical parameters in terahertz transmission spectroscopy.

    PubMed

    Son, Heyjin; Choi, Da-Hye; Park, Gun-Sik

    2017-02-20

    In terahertz transmission spectroscopy, there is a typical problem of thickness uncertainty, which hampers to determine precise optical parameters of samples. In order to resolve this experimental problem, a method optimizing sample thickness using singly subtractive Kramers-Kronig relations is proposed. For tens of micrometers thick water samples, we improved the accuracy of sample thickness by an order of magnitude (up to sub-micrometer) using the algorithm leading to obtain precise optical parameters of water. The broad applicability of the method is demonstrated for measuring various materials in addition to highly absorbing liquid water in the spectral range from 0.3 to 1.6 THz.

  5. Metabolism and biological functions of human milk oligosaccharides.

    PubMed

    Bertino, E; Peila, C; Giuliani, F; Martano, C; Cresi, F; Di Nicola, P; Occhi, L; Sabatino, G; Fabris, C

    2012-01-01

    It is well known that breastfeeding is beneficial both for its nutritional properties and for the presence of biologically active compounds. Among these, human milk oligosaccharides (HMOs), representing the third largest fraction of human milk, have been assigned important biological functions, such as prebiotic and immunomodulatory and antimicrobial effects. HMOs are synthesized in the mammary gland by glycosyltransferase enzymes and can be divided in core-oligosaccharides, sialo-oligosaccharides, fucosyl-oligosaccharides and sialo-fucosyl-oligosaccharides on the basis of their chemical structure. Glycosyltransferases enzymes are partially regulated by genetic mechanisms; according to the expression of secretory and Lewis' genes, it is possible to classify human milk in 4 different secretory groups. We hereby present a review of the current knowledge concerning HMOs, their metabolism and main biological functions.

  6. Structural analysis of oligosaccharide-alditols released by reductive beta-elimination from oviducal mucins of Rana dalmatina.

    PubMed

    Morelle, W; Guyétant, R; Strecker, G

    1998-01-01

    The O-linked oligosaccharides of the jelly coat surrounding the eggs of Rana dalmantina were released by alkaline borohydride treatment. Low-molecular-mass, monosialyl oligosaccharide-alditols were isolated by anion-exchange chromatography and fractionated by consecutive normal-phase high-performance liquid chromatography on a silica-based alkylamine column. The structures of the oligosaccharide-alditols were determined by 400-MHz 1H-NMR spectroscopy in combination with matrix assisted laser desorption ionization-time of flight analysis. The five structures were identified range in size from trisaccharides to hexasaccharides, possessing a core consisting of Gal(beta 1-3)GalNAc-ol (core type 1). Novel oligosaccharide-alditols are: [formula: see text] The carbohydrate chains isolated from Rana dalmatina are different from those found in other amphibian species, in which the presence of species-specific material has been characterized. Since the role of carbohydrates appears more and more apparent during the fertilization process, the biodiversity of the O-linked oligosaccharides could support such a biological role.

  7. Multifunctional fructans and raffinose family oligosaccharides

    PubMed Central

    den Ende, Wim Van

    2013-01-01

    Fructans and raffinose family oligosaccharides (RFOs) are the two most important classes of water-soluble carbohydrates in plants. Recent progress is summarized on their metabolism (and regulation) and on their functions in plants and in food (prebiotics, antioxidants). Interest has shifted from the classic inulin-type fructans to more complex fructans. Similarly, alternative RFOs were discovered next to the classic RFOs. Considerable progress has been made in the understanding of structure–function relationships among different kinds of plant fructan metabolizing enzymes. This helps to understand their evolution from (invertase) ancestors, and the evolution and role of so-called “defective invertases.” Both fructans and RFOs can act as reserve carbohydrates, membrane stabilizers and stress tolerance mediators. Fructan metabolism can also play a role in osmoregulation (e.g., flower opening) and source–sink relationships. Here, two novel emerging roles are highlighted. First, fructans and RFOs may contribute to overall cellular reactive oxygen species (ROS) homeostasis by specific ROS scavenging processes in the vicinity of organellar membranes (e.g., vacuole, chloroplasts). Second, it is hypothesized that small fructans and RFOs act as phloem-mobile signaling compounds under stress. It is speculated that such underlying antioxidant and oligosaccharide signaling mechanisms contribute to disease prevention in plants as well as in animals and in humans. PMID:23882273

  8. Analysis of Milk Oligosaccharides by Mass Spectrometry.

    PubMed

    Wu, Lauren D; Ruhaak, L Renee; Lebrilla, Carlito B

    2017-01-01

    Human milk oligosaccharides (HMOs) are a highly abundant constituent in human milk, and its protective and prebiotic properties have attracted considerable attention. HMOs have been shown to directly and indirectly benefit the overall health of the infant due to a number of functions including serving as a beneficial food for gut bacteria, block to pathogens, and aiding in brain development. Researchers are currently exploring whether these structures may act as possible disease and nutrition biomarkers. Because of this, rapid-throughput methods are desired to investigate biological activity in large patient sets. We have optimized a rapid-throughput protocol to analyze human milk oligosaccharides using micro-volumes of human breast milk for nutritional biomarkers. This method may additionally be applied to other biological fluid substrates such as plasma, urine, and feces. The protocol involves lipid separation via centrifugation, protein precipitation using ethanol, alditol reduction with sodium borohydride, and a final solid-phase extraction purification step using graphitized carbon cartridges. Samples are analyzed using HPLC-Chip/TOF-MS and data filtered on Agilent MassHunter using an in-house library. Individual structural identification is matched against a previously developed HMO library using accurate mass and retention time. Using this method will allow in-depth characterization and profiling of HMOs in large patient sets, and will ease the process of discovering significant nutritional biomarkers in human milk.

  9. A rationally engineered yeast pyruvyltransferase Pvg1p introduces sialylation-like properties in neo-human-type complex oligosaccharide.

    PubMed

    Higuchi, Yujiro; Yoshinaga, Sho; Yoritsune, Ken-Ichi; Tateno, Hiroaki; Hirabayashi, Jun; Nakakita, Shin-Ichi; Kanekiyo, Miho; Kakuta, Yoshimitsu; Takegawa, Kaoru

    2016-05-19

    Pyruvylation onto the terminus of oligosaccharide, widely seen from prokaryote to eukaryote, confers negative charges on the cell surface and seems to be functionally similar to sialylation, which is found at the end of human-type complex oligosaccharide. However, detailed molecular mechanisms underlying pyruvylation have not been clarified well. Here, we first determined the crystal structure of fission yeast pyruvyltransferase Pvg1p at a resolution of 2.46 Å. Subsequently, by combining molecular modeling with mutational analysis of active site residues, we obtained a Pvg1p mutant (Pvg1p(H168C)) that efficiently transferred pyruvyl moiety onto a human-type complex glycopeptide. The resultant pyruvylated human-type complex glycopeptide recognized similar lectins on lectin arrays as the α2,6-sialyl glycopeptides. This newly-generated pyruvylation of human-type complex oligosaccharides would provide a novel method for glyco-bioengineering.

  10. A rationally engineered yeast pyruvyltransferase Pvg1p introduces sialylation-like properties in neo-human-type complex oligosaccharide

    PubMed Central

    Higuchi, Yujiro; Yoshinaga, Sho; Yoritsune, Ken-ichi; Tateno, Hiroaki; Hirabayashi, Jun; Nakakita, Shin-ichi; Kanekiyo, Miho; Kakuta, Yoshimitsu; Takegawa, Kaoru

    2016-01-01

    Pyruvylation onto the terminus of oligosaccharide, widely seen from prokaryote to eukaryote, confers negative charges on the cell surface and seems to be functionally similar to sialylation, which is found at the end of human-type complex oligosaccharide. However, detailed molecular mechanisms underlying pyruvylation have not been clarified well. Here, we first determined the crystal structure of fission yeast pyruvyltransferase Pvg1p at a resolution of 2.46 Å. Subsequently, by combining molecular modeling with mutational analysis of active site residues, we obtained a Pvg1p mutant (Pvg1pH168C) that efficiently transferred pyruvyl moiety onto a human-type complex glycopeptide. The resultant pyruvylated human-type complex glycopeptide recognized similar lectins on lectin arrays as the α2,6-sialyl glycopeptides. This newly-generated pyruvylation of human-type complex oligosaccharides would provide a novel method for glyco-bioengineering. PMID:27194449

  11. High-precision half-life determination for the superallowed {beta}{sup +} emitter {sup 62}Ga

    SciTech Connect

    Grinyer, G. F.; Finlay, P.; Svensson, C. E.; Bandyopadhyay, D.; Hyland, B.; Leach, K. G.; Phillips, A. A.; Schumaker, M. A.; Wong, J.; Ball, G. C.; Chakrawarthy, R. S.; Hackman, G.; Kanungo, R.; Morton, A. C.; Pearson, C. J.; Savajols, H.; Leslie, J. R.; Austin, R. A. E.; Chaffey, A.; Garrett, P. E.

    2008-01-15

    The half-life of the superallowed {beta}{sup +} emitter {sup 62}Ga has been measured at TRIUMF's Isotope Separator and Accelerator facility using a fast-tape-transport system and 4{pi} continuous-flow gas proportional counter to detect the positrons from the decay of {sup 62}Ga to the daughter {sup 62}Zn. The result, T{sub 1/2}=116.100{+-}0.025 ms, represents the most precise measurement to date (0.022%) for any superallowed {beta}-decay half-life. When combined with six previous measurements of the {sup 62}Ga half-life, a new world average of T{sub 1/2}=116.121{+-}0.021 ms is obtained. This new half-life measurement results in a 20% improvement in the precision of the {sup 62}Ga superallowed ft value while reducing its mean by 0.9{sigma} to ft=3074.3(12) s. The impact of this half-life measurement on precision tests of the CVC hypothesis and isospin symmetry breaking corrections for A{>=}62 superallowed decays is discussed.

  12. Structural analysis of the asparagine-linked oligosaccharides of cholinesterases. N-linked carbohydrates of cholinesterases

    SciTech Connect

    Saxena, A.; Doctor, B.P.

    1995-12-31

    Cholinesterases are serine esterases that hydrolyse choline esters faster than other substrates. They are highly glycosylated proteins with up to 24% of their molecular weight constituted of carbohydrates. Here we report the results of our studies on the glycosylation of fetal bovine serum acetylcholinesterase (FBS AChE) and horse serum butyrylcholinesterase (Eq BChE). Analysis of the monosaccharide content of the two enzymes indicated that Eq BChE contained 520 nmoles of monosaccharide/mg protein, as compared to 1290 nmoles/mg protein for Eq BChE. Both enzymes contained mannose, galactose, N-acetylglucosamine and sialic acid. Fucose was present in Eq BChE only. The structures of the two major oligosaccharides from FBS AChE and one major oligosaccharide from Eq BChE were determined and found to be very similar except that one of the oligosaccharides from FBS AChE contained a galactose alphal-3 galactose betal-4-determinant which has been identified as a potentially immunogenic determinant.

  13. Structural characterization of neutral oligosaccharides with blood-group A and H activity isolated from bovine submaxillary mucin.

    PubMed Central

    Savage, A V; D'Arcy, S M; Donoghue, C M

    1991-01-01

    In this study we investigated the structures of 11 neutral oligosaccharides released from bovine submaxillary mucin by alkaline borohydride treatment and isolated by h.p.l.c. One hexa-, one penta-, three tetra-, four tri- and two di-saccharides containing core types 1, 2, 3 or 4 were obtained. We report their structures, determined by a combination of one- and two-dimensional 1H n.m.r. spectroscopy at 270 MHz and methylation analysis involving g.l.c.-m.s., along with their approximate molar ratios. Only three of these oligosaccharides have previously been reported in this source. Of the new oligosaccharides, one contains the blood-group-A antigenic determinant, two contain the blood-group-H type 2 determinant, while another contains the blood-group-H type 3 determinant. The oligosaccharide GlcNAc beta (1----6)[GlcNAc beta (1----3)]GalNAcol, although previously found as a core structure, has been isolated here as a novel trisaccharide. PMID:1718265

  14. Typing of blood-group antigens on neutral oligosaccharides by negative-ion electrospray ionization tandem mass spectrometry.

    PubMed

    Zhang, Hongtao; Zhang, Shuang; Tao, Guanjun; Zhang, Yibing; Mulloy, Barbara; Zhan, Xiaobei; Chai, Wengang

    2013-06-18

    Blood-group antigens, such as those containing fucose and bearing the ABO(H)- and Lewis-type determinants expressed on the carbohydrate chains of glycoproteins and glycolipids, and also on unconjugated free oligosaccharides in human milk and other secretions, are associated with various biological functions. We have previously shown the utility of negative-ion electrospay ionization tandem mass spectrometry with collision-induced dissociation (ESI-CID-MS/MS) for typing of Lewis (Le) determinants, for example, Le(a), Le(x), Le(b), and Le(y) on neutral and sialylated oligosaccharide chains. In the present report, we extended the strategy to characterization of blood-group A-, B-, and H-determinants on type 1 and type 2 and also on type 4 globoside chains to provide a high sensitivity method for typing of all the major blood-group antigens, including the A, B, H, Le(a), Le(x), Le(b), and Le(y) determinants, present in oligosaccharides. Using the principles established, we identified two minor unknown oligosaccharide components present in the products of enzymatic synthesis by bacterial fermentation. We also demonstrated that the unique fragmentations derived from the D- and (0,2)A-type cleavages observed in ESI-CID-MS/MS, which are important for assigning blood-group and chain types, only occur under the negative-ion conditions for reducing sugars but not for reduced alditols or under positive-ion conditions.

  15. High-precision atmospheric parameter and abundance determination of massive stars, and consequences for stellar and Galactic evolution

    NASA Astrophysics Data System (ADS)

    Nieva, Maria-Fernanda; Przybilla, Norbert; Irrgang, Andreas

    2011-12-01

    The derivation of high precision/accuracy parameters and chemical abundances of massive stars is of utmost importance to the fields of stellar evolution and Galactic chemical evolution. We concentrate on the study of OB-type stars near the main sequence and their evolved progeny, the BA-type supergiants, covering masses of ~6 to 25 solar masses and a range in effective temperature from ~8000 to 35 000 K. The minimization of the main sources of systematic errors in the atmospheric model computation, the observed spectra and the quantitative spectral analysis play a critical role in the final results. Our self-consistent spectrum analysis technique employing a robust non-LTE line formation allows precise atmospheric parameters of massive stars to be derived, achieving 1σ-uncertainties as low as 1% in effective temperature and ~0.05-0.10 dex in surface gravity. Consequences on the behaviour of the chemical elements carbon, nitrogen and oxygen are discussed here in the context of massive star evolution and Galactic chemical evolution, showing tight relations covered in previous work by too large statistical and systematic uncertainties. The spectral analysis of larger star samples, like from the upcoming Gaia-ESO survey, may benefit from these findings.

  16. SAR Interferometry and Precise Leveling for the Determination of Vertical Displacements in the Upper Rhine Graben Area, Southwest Germany

    NASA Astrophysics Data System (ADS)

    Fuhrmann, T.; Schenk, A.; Westerhaus, M.; Zippelt, K.; Heck, B.

    2013-12-01

    The PS-InSAR (Persistent Scatterer SAR Interferometry) method and precise levelings provide a unique database to detect recent displacements of the Earth's surface. Data of both measurement techniques are analyzed at Geodetic Institute, Karlsruhe Institute of Technology, in order to gain detailed insight into the velocity field of the Upper Rhine Graben (URG). As central and most prominent segment of the European Cenozoic rift system, the seismically and tectonically active Rhine Graben is of steady geo-scientific interest. In the last decades, the URG is characterized by small tectonic movements (< 1mm/a), but an extensive use of its geopotentials (mining, groundwater usage, oil extraction, geothermal energy) inducing larger surface displacements. To assess the geohazards in the URG area, we aim to provide a map of the current 3D surface displacements with high precision and high spatial resolution. The InSAR and leveling data, and the location of permanent GNSS sites primarily analyzed for the horizontal velocity field, are displayed in Fig. 1. Precise levelings have been carried out by the surveying authorities of Germany, France and Switzerland over the last 100 years building a network of leveling lines. A kinematic network adjustment is applied on the leveling data, providing an accurate solution for vertical displacement rates with accuracies of 0.2 to 0.4 mm/a. The biggest disadvantage of the leveling database is the sparse spatial distribution of the measurement points. Therefore, PS-InSAR is used to significantly increase the number of points within the leveling loops. To obtain a high accuracy for line of sight displacement rates, ERS-1/2 and Envisat data from ascending and descending orbits covering a period from 1992 to 2000 and 2002 to 2010, resp., are processed using StaMPS (Stanford Method for Persistent Scatterers). As the tectonic displacements cover a large area, the separation of atmospheric effects and orbit errors plays an important role in

  17. LC-MSn Analysis of Isomeric Chondroitin Sulfate Oligosaccharides Using a Chemical Derivatization Strategy

    PubMed Central

    Huang, Rongrong; Pomin, Vitor H.; Sharp, Joshua S.

    2011-01-01

    Improved methods for structural analyses of glycosaminoglycans (GAGs) are required to understand their functional roles in various biological processes. Major challenges in structural characterization of complex GAG oligosaccharides using liquid chromatography-mass spectrometry (LC-MS) include the accurate determination of the patterns of sulfation due to gas-phase losses of the sulfate groups upon collisional activation and inefficient on-line separation of positional sulfation isomers prior to MS/MS analyses. Here, a sequential chemical derivatization procedure including permethylation, desulfation, and acetylation was demonstrated to enable both on-line LC separation of isomeric mixtures of chondroitin sulfate (CS) oligosaccharides and accurate determination of sites of sulfation by MSn. The derivatized oligosaccharides have sulfate groups replaced with acetyl groups, which are sufficiently stable to survive MSn fragmentation and reflect the original sulfation patterns. A standard reversed-phase LC-MS system with a capillary C18 column was used for separation, and MSn experiments using collision-induced dissociation (CID) were performed. Our results indicate that the combination of this derivatization strategy and MSn methodology enables accurate identification of the sulfation isomers of CS hexasaccharides with either saturated or unsaturated nonreducing ends. Moreover, derivatized CS hexasaccharide isomer mixtures become separable by LC-MS method due to different positions of acetyl modifications. PMID:21953261

  18. Precision determination of the πN scattering lengths and the charged πNN coupling constant

    NASA Astrophysics Data System (ADS)

    Ericson, T. E. O.; Loiseau, B.; Thomas, A. W.

    2000-01-01

    We critically evaluate the isovector GMO sumrule for the charged πNN coupling constant using recent precision data from π-p and π-d atoms and with careful attention to systematic errors. From the π-d scattering length we deduce the pion-proton scattering lengths 1/2(aπ-p + aπ-n) = (-20 +/- 6(statistic)+/-10 (systematic) .10-4m-1πc and 1/2(aπ-p - aπ-n) = (903 +/- 14) . 10-4m-1πc. From this a direct evaluation gives g2c(GMO)/4π = 14.20 +/- 0.07 (statistic)+/-0.13(systematic) or f2c/4π = 0.0786 +/- 0.0008.

  19. Precision Measurement.

    ERIC Educational Resources Information Center

    Radius, Marcie; And Others

    The manual provides information for precision measurement (counting of movements per minute of a chosen activity) of achievement in special education students. Initial sections give guidelines for the teacher, parent, and student to follow for various methods of charting behavior. It is explained that precision measurement is a way to measure the…

  20. High mannose oligosaccharide of phytohemagglutinin is attached to asparagine 12 and the modified oligosaccharide to asparagine 60. [Phaseolus vulgaris

    SciTech Connect

    Sturm, A.; Chrispeels, M.J.

    1986-05-01

    Phytohemagglutinin, the lectin of the common bean Phaseolus vulgaris, has a high mannose and a modified (fucosylated) oligosaccharide on each polypeptide. Fractionation by high performance liquid chromatography of tryptic digests of (/sup 3/H)fucose or (/sup 3/H)glucosamine labeled phytohemagglutinin, followed by amino acid sequencing of the isolated glycopeptides, shows that the high mannose oligosaccharide is attached to Asn/sup 12/ and the modified oligosaccharide to Asn /sup 60/ of the protein. In animal glycoproteins, high mannose chains are rarely found at the N-terminal side of complex chains.

  1. Breakthrough in orbit determination of a binary. - In expectation of astrometric observations with high precision such as VERA and JASMINE -

    NASA Astrophysics Data System (ADS)

    Asada, Hideki

    2006-11-01

    There exists a very classical inverse problem regarding orbit determination of a binary system: "when an orbital plane of two bodies is inclined with respect to the line of sight, observables are their positions projected onto a celestial sphere. How do we determine the orbital elements from observations?" A "complete exact solution" has been found. It is reviewed with some related topics.

  2. Applications of mass spectrometry to structural analysis of marine oligosaccharides.

    PubMed

    Lang, Yinzhi; Zhao, Xia; Liu, Lili; Yu, Guangli

    2014-06-30

    Marine oligosaccharides have attracted increasing attention recently in developing potential drugs and biomaterials for their particular physical and chemical properties. However, the composition and sequence analysis of marine oligosaccharides are very challenging for their structural complexity and heterogeneity. Mass spectrometry (MS) has become an important technique for carbohydrate analysis by providing more detailed structural information, including molecular mass, sugar constituent, sequence, inter-residue linkage position and substitution pattern. This paper provides an overview of the structural analysis based on MS approaches in marine oligosaccharides, which are derived from some biologically important marine polysaccharides, including agaran, carrageenan, alginate, sulfated fucan, chitosan, glycosaminoglycan (GAG) and GAG-like polysaccharides. Applications of electrospray ionization mass spectrometry (ESI-MS) are mainly presented and the general applications of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) are also outlined. Some technical challenges in the structural analysis of marine oligosaccharides by MS have also been pointed out.

  3. Applications of Mass Spectrometry to Structural Analysis of Marine Oligosaccharides

    PubMed Central

    Lang, Yinzhi; Zhao, Xia; Liu, Lili; Yu, Guangli

    2014-01-01

    Marine oligosaccharides have attracted increasing attention recently in developing potential drugs and biomaterials for their particular physical and chemical properties. However, the composition and sequence analysis of marine oligosaccharides are very challenging for their structural complexity and heterogeneity. Mass spectrometry (MS) has become an important technique for carbohydrate analysis by providing more detailed structural information, including molecular mass, sugar constituent, sequence, inter-residue linkage position and substitution pattern. This paper provides an overview of the structural analysis based on MS approaches in marine oligosaccharides, which are derived from some biologically important marine polysaccharides, including agaran, carrageenan, alginate, sulfated fucan, chitosan, glycosaminoglycan (GAG) and GAG-like polysaccharides. Applications of electrospray ionization mass spectrometry (ESI-MS) are mainly presented and the general applications of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) are also outlined. Some technical challenges in the structural analysis of marine oligosaccharides by MS have also been pointed out. PMID:24983643

  4. Synbiotic matrices derived from plant oligosaccharides and polysaccharides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A porous synbiotic matrix was prepared by lyophilization of alginate and pectin or fructan oligosaccharides and polysaccharides cross-linked with calcium. These synbiotic matrices were excellent physical structures to support the growth of Lactobacillus acidophilus (1426) and Lactobacillus reuteri (...

  5. The importance of precision radar tracking data for the determination of density and winds from the high-altitude inflatable sphere

    NASA Technical Reports Server (NTRS)

    Schmidlin, F. J.; Michel, W. R.

    1985-01-01

    Analysis of inflatable sphere measurements obtained during the Energy Budget and MAP/WINE campaigns led to questions concerning the precision of the MPS-36 radar used for tracking the spheres; the compatibility of the sphere program with the MPS-36 radar tracking data; and the oversmoothing of derived parameters at high altitudes. Simulations, with winds having sinusoidal vertical wavelengths, were done with the sphere program (HIROBIN) to determine the resolving capability of various filters. It is concluded that given a precision radar and a perfectly performing sphere, the HIROBIN filters can be adjusted to provide small-scale perturbation information to 70 km (i.e., sinusoidal wavelengths of 2 km). It is recommended that the HIROBIN program be modified to enable it to use a variable length filter, that adjusts to fall velocity and accelerations to provide wind data with small perturbations.

  6. Innovations in Mass Spectrometry for Precise and Accurate Isotope Ratio Determination from Very Small Analyte Quantities (Invited)

    NASA Astrophysics Data System (ADS)

    Lloyd, N. S.; Bouman, C.; Horstwood, M. S.; Parrish, R. R.; Schwieters, J. B.

    2010-12-01

    This presentation describes progress in mass spectrometry for analysing very small analyte quantities, illustrated by example applications from nuclear forensics. In this challenging application, precise and accurate (‰) uranium isotope ratios are required from 1 - 2 µm diameter uranium oxide particles, which comprise less than 40 pg of uranium. Traditionally these are analysed using thermal ionisation mass spectrometry (TIMS), and more recently using secondary ionisation mass spectrometry (SIMS). Multicollector inductively-coupled plasma mass spectrometry (MC-ICP-MS) can offer higher productivity compared to these techniques, but is traditionally limited by low efficiency of analyte utilisation (sample through to ion detection). Samples can either be introduced as a solution, or sampled directly from solid using laser ablation. Large multi-isotope ratio datasets can help identify provenance and intended use of anthropogenic uranium and other nuclear materials [1]. The Thermo Scientific NEPTUNE Plus (Bremen, Germany) with ‘Jet Interface’ option offers unparalleled MC-ICP-MS sensitivity. An analyte utilisation of c. 4% has previously been reported for uranium [2]. This high-sensitivity configuration utilises a dry high-capacity (100 m3/h) interface pump, special skimmer and sampler cones and a desolvating nebuliser system. Coupled with new acquisition methodologies, this sensitivity enhancement makes possible the analysis of micro-particles and small sample volumes at higher precision levels than previously achieved. New, high-performance, full-size and compact discrete dynode secondary electron multipliers (SEM) exhibit excellent stability and linearity over a large dynamic range and can be configured to simultaneously measure all of the uranium isotopes. Options for high abundance-sensitivity filters on two ion beams are also available, e.g. for 236U and 234U. Additionally, amplifiers with high ohm (1012 - 1013) feedback resistors have been developed to

  7. Recent Advances in the Synthesis of C-oligosaccharides

    PubMed Central

    Yuan, Xuejun; Linhardt, Robert J.

    2014-01-01

    This paper reviews the recent advances in the synthesis of catabolically stable sugar mimetics, C-oligosaccharides. These compounds are synthetic analogs of the naturally occurring O-oligosaccharides, in which the interglycosidic oxygen has been replaced by a methylene group. This review is organized in terms of chemistry used to assemble C-oligosaccarides under the sub-headings: anionic approaches, cationic methods, reductive glycosyl samarium chemistry, cyclization methodology, and free radical chemistry. PMID:16305537

  8. Precise determination of the 1s Lamb shift in hydrogen-like lead and gold using microcalorimeters

    NASA Astrophysics Data System (ADS)

    Kraft-Bermuth, S.; Andrianov, V.; Bleile, A.; Echler, A.; Egelhof, P.; Grabitz, P.; Ilieva, S.; Kiselev, O.; Kilbourne, C.; McCammon, D.; Meier, J. P.; Scholz, P.

    2017-03-01

    Quantum electrodynamics in very strong Coulomb fields is one scope which has not yet been tested experimentally with sufficient accuracy to really determine whether the perturbative approach is valid. One sensitive test is the determination of the 1s Lamb shift in highly-charged very heavy ions. The 1s Lamb shift of hydrogen-like lead (Pb81+) and gold (Au78+) has been determined using the novel detector concept of silicon microcalorimeters for the detection of hard x-rays. The results of (260+/- 53) eV for lead and (211+/- 42) eV for gold are within the error bars in good agreement with theoretical predictions. To our knowledge, for hydrogen-like lead, this represents the most accurate determination of the 1s Lamb shift.

  9. Precision Medicine

    PubMed Central

    Cholerton, Brenna; Larson, Eric B.; Quinn, Joseph F.; Zabetian, Cyrus P.; Mata, Ignacio F.; Keene, C. Dirk; Flanagan, Margaret; Crane, Paul K.; Grabowski, Thomas J.; Montine, Kathleen S.; Montine, Thomas J.

    2017-01-01

    Three key elements to precision medicine are stratification by risk, detection of pathophysiological processes as early as possible (even before clinical presentation), and alignment of mechanism of action of intervention(s) with an individual's molecular driver(s) of disease. Used for decades in the management of some rare diseases and now gaining broad currency in cancer care, a precision medicine approach is beginning to be adapted to cognitive impairment and dementia. This review focuses on the application of precision medicine to address the clinical and biological complexity of two common neurodegenerative causes of dementia: Alzheimer disease and Parkinson disease. PMID:26724389

  10. Double-resonance spectroscopy of the high Rydberg states of HCO. I. A precise determination of the adiabatic ionization potential

    NASA Astrophysics Data System (ADS)

    Mayer, Eric; Grant, Edward R.

    1995-12-01

    We report the first spectroscopic observation of the high Rydberg states of HCO. Individual lines in a system of vibrationally autoionizing Rydberg series converging to the (010) state of HCO+ are rotationally labeled in a double-resonance excitation scheme that uses resolved levels in the (010) A' vibronic component of the 3pπ 2Π Rydberg state as intermediates. Observed high-Rydberg structure extends from the adiabatic ionization threshold—which falls just below the principal quantum number of 12 in the vibrationally excited series—to the (010) vertical threshold. Elements of a single series extending from n=12 to 50, for which the total angular momentumless spin can be assigned as N=1, are extrapolated to obtain a vertical convergence limit with respect to the 3pπ 2Π(010)A' N'=0 intermediate state of 20 296.9±0.3 cm-1. Referring this transition energy to the ground state, and subtracting the precisely known fundamental bending frequency of the cation, establishes the adiabatic ionization potential corresponding to the transition from HCO 2A'(000) J″=0, K″=0 to HCO+ J+=0 1Σ+(000). The result is 65 735.9±0.5 cm-1 or 8.150 22±0.000 06 eV.

  11. Quantitative Thin-Film X-ray Microanalysis by STEM/HAADF: Statistical Analysis for Precision and Accuracy Determination

    NASA Astrophysics Data System (ADS)

    Armigliato, Aldo; Balboni, Roberto; Rosa, Rodolfo

    2006-07-01

    Silicon-germanium thin films have been analyzed by EDS microanalysis in a field emission gun scanning transmission electron microscope (FEG-STEM) equipped with a high angular dark-field detector (STEM/HAADF). Several spectra have been acquired in the same homogeneous area of the cross-sectioned sample by drift-corrected linescan acquisitions. The Ge concentrations and the local film thickness have been obtained by using a previously described Monte Carlo based “two tilt angles” method. Although the concentrations are in excellent agreement with the known values, the resulting confidence intervals are not as good as expected from the precision in beam positioning and tilt angle position and readout offered by our state-of-the-art microscope. The Gaussian shape of the SiK[alpha] and GeK[alpha] X-ray intensities allows one to use the parametric bootstrap method of statistics, whereby it becomes possible to perform the same quantitative analysis in sample regions of different compositions and thicknesses, but by doing only one measurement at the two angles.

  12. Precise determination of nonlinear function of ion mobility for explosives and drugs at high electric fields for microchip FAIMS.

    PubMed

    Guo, Dapeng; Wang, Yonghuan; Li, Lingfeng; Wang, Xiaozhi; Luo, Jikui

    2015-01-01

    High-field asymmetric waveform ion mobility spectrometry (FAIMS) separates ions by utilizing the characteristics of nonlinear ion mobility at high and low electric fields. Accurate ion discrimination depends on the precise solution of nonlinear relationships and is essential for accurate identification of ion species for applications. So far, all the nonlinear relationships of ion mobility obtained are based at low electric fields (E/N <65 Td). Microchip FAIMS (μ-FAIMS) with small dimensions has high electric field up to E/N = 250 Td, making the approximation methods and conclusions for nonlinear relationships inappropriate for these systems. In this paper, we deduced nonlinear functions based on the first principle and a general model. Furthermore we considered the hydrodynamics of gas flow through microchannels. We then calculated the specific alpha coefficients for cocaine, morphine, HMX, TNT and RDX, respectively, based on their FAIMS spectra measured by μ-FAIMS system at ultra-high fields up to 250 Td. The results show that there is no difference in nonlinear alpha functions obtained by the approximation and new method at low field (<120 Td), but the error induced by using approximation method increases monotonically with the increase in field, and could be as much as 30% at a field of 250 Td.

  13. Precisely determined the surface displacement by the ionospheric mitigation using the L-band SAR Interferometry over Mt.Baekdu

    NASA Astrophysics Data System (ADS)

    Lee, Won-Jin; Jung, Hyung-Sup; Park, Sun-Cheon; Lee, Duk Kee

    2016-04-01

    Mt. Baekdu (Changbaishan in Chinese) is located on the border between China and North Korea. It has recently attracted the attention of volcanic unrest during 2002-2005. Many researchers have applied geophysical approaches to detect magma system of beneath Mt.Baekdu such as leveling, Global Positioning System (GPS), gases analysis, seismic analysis, etc. Among them, deformation measuring instruments are important tool to evaluate for volcanism. In contrast to GPS or other deformation measuring instruments, Synthetic Aperture Radar Interferometry (InSAR) has provided high resolution of 2-D surface displacement from remote sensed data. However, Mt. Baekdu area has disturbed by decorrelation on interferogram because of wide vegetation coverage. To overcome this limitation, L-band system of long wavelength is more effective to detect surface deformation. In spite of this advantage, L-band can surfer from more severe ionospheric phase distortions than X- or C- band system because ionospheric phase distortions are inverse proportion to the radar frequency. Recently, Multiple Aperture Interferometry (MAI) based ionospheric phase distortions mitigation method have proposed and investigated. We have applied this technique to the Mt.Baekdu area to measure surface deformation precisely using L-band Advanced Land Observing Satellite-1(ALOS-1) Phased Array type L-band Synthetic Aperture Radar(PALSAR) data acquiring from 2006 to 2011.

  14. Micrometer-Precise Determination of the Thin Electrolyte Layer of a Spectroelectrochemical Cell by Microelectrode Approach Curves.

    PubMed

    Hiltrop, Dennis; Masa, Justus; Botz, Alexander J R; Lindner, Armin; Schuhmann, Wolfgang; Muhler, Martin

    2017-03-31

    A spectroelectrochemical cell is presented that allows investigations of electrochemical reactions by means of attenuated total reflection infrared (ATR-IR) spectroscopy. The electrode holder for the working (WE), counter and reference electrode as mounted in the IR spectrometer cause the formation of a thin electrolyte layer between the internal reflection element (IRE) and the surface of the WE. The thickness of this thin electrolyte layer (dTL) was estimated by performing a scanning electrochemical microscopy-(SECM) like approach of a Pt microelectrode (ME), which was leveled with the WE toward the IRE surface. The precise lowering of the ME/WE plane toward the IRE was enabled by a micrometer screw. The approach curve was recorded in negative feedback mode of SECM and revealed the contact point of the ME and WE on the IRE, which was used as reference point to perform the electro-oxidation of ethanol over a drop-casted Pd/NCNT catalyst on the WE at different thin-layer thicknesses by cyclic voltammetry. The reaction products were detected in the liquid electrolyte by IR spectroscopy, and the effect of variations in dTL on the current densities and IR spectra were analyzed and discussed. The obtained data identify dTL as an important variable in thin-layer experiments with electrochemical reactions and FTIR readout.

  15. Fluorographic detection of tritiated glycopeptides and oligosaccharides separated on polyacrylamide gels: analysis of glycans from Dictyostelium discoideum glycoproteins

    SciTech Connect

    Prem Das, O.; Henderson, E.J.

    1986-11-01

    Previous workers have shown that oligosaccharides and glycopeptides can be separated by electrophoresis in buffers containing borate ions. However, normal fluorography of tritium-labeled structures cannot be performed because the glycans are soluble and can diffuse during equilibration with scintillants. This problem has been circumvented by equilibration of the gel with 2,5-diphenyloxazole (PPO) prior to electrophoresis. The presence of PPO in the gel during electrophoresis does not alter mobility of the glycopeptides and oligosaccharides. After electrophoresis, the gel is simply dried and fluorography performed. This allows sensitive and precise comparisons of labeled samples in parallel lanes of a slab gel and, since mobilities are highly reproducible, between different gels. The procedure is preparative in that after fluorography the gel bands can be quantitatively eluted for further study, without any apparent modification by the procedure. In this report, the procedure is illustrated by fractionation of both neutral and anionic glycopeptides produced by the cellular slime mold Dictyostelium discoideum.

  16. Beneficial effects of human milk oligosaccharides on gut microbiota.

    PubMed

    Musilova, S; Rada, V; Vlkova, E; Bunesova, V

    2014-09-01

    Human milk is the gold standard for nourishment of early infants because it contains a number of bioactive components, such as human milk oligosaccharides (HMOs). The high concentration and structural diversity of HMOs are unique to humans. HMOs are a group of complex and diverse glycans that are resistant to gastrointestinal digestion and reach the infant colon as the first prebiotics. N-acetyl-glucosamine containing oligosaccharides were first identified 50 years ago as the 'bifidus factor', a selective growth substrate for intestinal bifidobacteria, thus providing a conceptual basis for HMO-specific bifidogenic activity. Bifidobacterial species are the main utilisers of HMOs in the gastrointestinal tract and represent the dominant microbiota of breast-fed infants, and they may play an important role in maintaining the general health of newborn children. Oligosaccharides are also known to directly interact with the surface of pathogenic bacteria, and various oligosaccharides in milk are believed to inhibit the binding of pathogens and toxins to host cell receptors. Furthermore, HMOs are thought to contribute to the development of infant intestine and brain. Oligosaccharides currently added to infant formula are structurally different from the oligosaccharides naturally occurring in human milk and, therefore, they are unlikely to mimic some of the structure-specific effects. In this review, we describe how HMOs can modulate gut microbiota. This article summarises information up to date about the relationship between the intestinal microbiota and HMOs, and other possible indirect effects of HMOs on intestinal environment.

  17. [Structural and functional aspects of oligosaccharides in human milk].

    PubMed

    Kunz, C; Rudloff, S

    1996-03-01

    About a century ago, pediatricians observed that in feces of breast-fed infants, compared to those of bottle-fed infants, Bifidobacterium bifidum was the predominant microorganism. It was shown thereafter that aminosugar-containing oligosaccharides are growth factors for a specific strain of Bifidobacterium. Meanwhile, more than 130 lactose-derived oligosaccharides have been identified in human milk. Some of these oligosaccharides like Lacto-N-Tetraose and Lacto-N-Fucopentaose I and II do not occur in minute amounts but in concentrations up to 1-2 g/L. As the total amount of complex oligosaccharides is between 3-6 g/L those components have to be considered as major human milk constituents. There is striking evidence that human milk oligosaccharides are potent inhibitors of bacterial adhesion to epithelial surfaces, an initial stage of infective processes. Therefore, these oligosaccharides are considered to be soluble receptor analogues of epithelial cell surfaces participating in the non-immunological defense system of human milk-fed infants.

  18. Precise determination of the 1s Lamb Shift in hydrogen-like heavy ions at the ESR storage ring using microcalorimeters

    NASA Astrophysics Data System (ADS)

    Kraft-Bermuth, S.; Andrianov, V.; Bleile, A.; Echler, A.; Egelhof, P.; Grabitz, P.; Ilieva, S.; Kiselev, O.; Kilbourne, C.; McCammon, D.; Meier, J. P.; Scholz, P.

    2015-11-01

    The precise determination of the energy of the Lyman α1 and α2 lines in hydrogen-like heavy ions provides a sensitive test of quantum electrodynamics in very strong Coulomb fields. To improve the precision of such experiments, the new detector concept of microcalorimeters, which detect the temperature change of an absorber after an incoming particle or photon has deposited its energy as heat, is now exploited. The microcalorimeters for x-rays used in these experiments consist of arrays of silicon thermometers and x-ray absorbers made of high-Z material. With such detectors, a relative energy resolution of about 1 per mille is obtained in the energy regime of 50-100 keV. Two successful measurement campaigns to determine the 1s Lamb Shift in Pb81+ and Au78+ have been completed: a prototype array has been applied successfully for the determination of the 1s Lamb Shift of Pb81+ at the ESR storage ring at GSI in a first test experiment. Based on the results of this test, a full array with 32 pixels has been equipped and has recently been applied to determine the 1s Lamb Shift in Au78+ ions. The energy of the Lyman-α1 line agrees within error bars well with theoretical predictions. The obtained accuracy is already comparable to the best accuracy obtained with conventional germanium detectors for hydrogen-like uranium.

  19. Crystal Structures of Escherichia coli Branching Enzyme in Complex with Linear Oligosaccharides.

    PubMed

    Feng, Lei; Fawaz, Remie; Hovde, Stacy; Gilbert, Lindsey; Chiou, Janice; Geiger, James H

    2015-10-13

    Branching enzyme is responsible for all branching of glycogen and starch. It is an unusual member of the α-amylase family because it has both α-1,4-amylase activity and α-1,6-transferase activity [Drummond, G. S., et al. (1972) Eur. J. Biochem. 26, 168-176]. It also does not react with shorter glucans, though it will bind much longer substrates and substrate mimics [Binderup, K., et al. (2002) Arch. Biochem. Biophys. 397, 279-285]. In an effort to better understand how branching enzyme interacts with its polymeric substrate, we have determined the structure of Δ112 Escherichia coli branching enzyme bound to maltoheptaose and maltohexaose. Together, these structures define six distinct oligosaccharide binding sites on the surface of E. coli branching enzyme. Most of these binding sites surround the edge of the β-barrel domain and are quite far from the active site. Surprisingly, there is no evidence of oligosaccharide binding in the active site of the enzyme. The closest bound oligosaccharide resides almost 18 Å from the active site. Mutations to conserved residues in binding sites I and VI had a debilitating effect on the activity of the enzyme.

  20. Enhancing real-time precise point positioning with zenith troposphere delay products and the determination of corresponding tropospheric stochastic models

    NASA Astrophysics Data System (ADS)

    Yao, Yibin; Peng, Wenjie; Xu, Chaoqian; Cheng, Shuyang

    2017-02-01

    By introducing two types of zenith troposphere delay (ZTD) products in precise point positioning (PPP), we developed the ZTD-corrected PPP and the ZTD-constrained PPP, both of them reduced the PPP convergence time. Both enhanced PPP methods are examined by global empirical ZTD models and regional ZTD corrections. For global ZTD models, we verified that ZTD-corrected PPP will deviate the positioning results, while ZTD-constrained PPP could produce unbiased estimations. Therefore, the latter is utilized to study the performance of global ZTD models (ITG, GPT2w, GZTD and UNB3m). After numerous experiments, we found that the performance of ZTD models was positively related to the real ZTD accuracy, and we proposed a universal tropospheric stochastic model 2SQR(9rms) which denotes double the square of nine times ZTD rms, to constrain ZTD in PPP. The proposed model subsequently was validated by real-time static and kinematic ZTD-constrained PPP on the premise that the ZTD rms on every station was known. Compared with traditional PPP, in static PPP, the number of improved stations is increased by 15.5 per cent (ITG), 14.4 per cent (GPT2w), 11.1 per cent (GZTD) and 8.3 per cent (UNB3m). For kinematic PPP, PPP constrained by ITG model still had the best performance, the number of improved stations is increased by 14.4 per cent, after 30 min of initialization time, 13.4 cm east, 13.4 cm north and 11.7 cm up positioning accuracy was obtained, compared with 15.3 cm east, 15.3 cm north and 14.3 cm up accuracy by traditional PPP. In addition, experiments using regional ZTD corrections to enhance real-time PPP showed that both ZTD-corrected PPP and ZTD-constrained PPP can notably reduce the convergence time on the vertical component (within 15 cm).

  1. New precise determination of the high temperature unusual temperature dependent thermopower of liquid divalent cadmium and zinc

    NASA Astrophysics Data System (ADS)

    Giordanengo, B.; Ben Moussa, A.; Makradi, A.; Chaaba, H.; Gasser, J.-G.

    2000-04-01

    We do not know any precise measurement of the absolute thermopower (ATP) of liquid cadmium and zinc at high temperatures. For liquid cadmium, there are, in the literature, apparent contradictory results. Bath and Kliem and North and Wagner observed that the ATP increases with temperature between 350 °C and 650 °C, but Bradley observed the opposite behaviour between 600 °C and 750 °C. In this work we measured accurately the absolute thermopower of liquid cadmium from the melting point up to 900 °C. We find a maximum around 520 °C, and then the thermopower decreases down to a surprising negative value. To our knowledge, it is the first time that such an unusual behaviour is reported. Nevertheless, it is qualitatively consistent with all the authors mentioned and the apparent contradictory results should only be due to the different temperature ranges of measurements. Using the ATP expression from the Faber-Ziman formalism, we can fit very well the experimental absolute thermopower versus temperature curve with only one adjustable parameter. For this, we have considered that the temperature dependence of the ATP is dominated by the resistivity, and we have introduced the experimental resistivity temperature dependence in the ATP expression. The very good fitting quality demonstrates that our hypothesis is consistent. In contrast, the liquid zinc ATP only increases with temperature. Nevertheless, near 1100 °C, the highest temperature achieved, it shows saturation that may be an indication of a decrease at higher temperature. The same type of fitting gives also quite good results.

  2. Precise oxygen and hydrogen isotope determination in nanoliter quantities of speleothem inclusion water by cavity ring-down spectroscopic techniques

    NASA Astrophysics Data System (ADS)

    Uemura, Ryu; Nakamoto, Masashi; Asami, Ryuji; Mishima, Satoru; Gibo, Masakazu; Masaka, Kosuke; Jin-Ping, Chen; Wu, Chung-Che; Chang, Yu-Wei; Shen, Chuan-Chou

    2016-01-01

    Speleothem inclusion-water isotope compositions are a promising new climatic proxy, but their applicability is limited by their low content in water and by analytical challenges. We have developed a precise and accurate isotopic technique that is based on cavity ring-down spectroscopy (CRDS). This method features a newly developed crushing apparatus, a refined sample extraction line, careful evaluation of the water/carbonate adsorption effect. After crushing chipped speleothem in a newly-developed crushing device, released inclusion water is purified and mixed with a limited amount of nitrogen gas in the extraction line for CRDS measurement. We have measured 50-260 nL of inclusion water from 77 to 286 mg of stalagmite deposits sampled from Gyokusen Cave, Okinawa Island, Japan. The small sample size requirement demonstrates that our analytical technique can offer high-resolution inclusion water-based paleoclimate reconstructions. The 1σ reproducibility for different stalagmites ranges from ±0.05 to 0.61‰ for δ18O and ±0.0 to 2.9‰ for δD. The δD vs. δ18O plot for inclusion water from modern stalagmites is consistent with the local meteoric water line. The 1000 ln α values based on calcite and fluid inclusion measurements from decades-old stalagmites are in agreement with the data from present-day farmed calcite experiment. Combination of coeval carbonate and fluid inclusion data suggests that past temperatures at 9-10 thousand years ago (ka) and 26 ka were 3.4 ± 0.7 °C and 8.2 ± 2.4 °C colder than at present, respectively.

  3. Verification on the use of the Inoue method for precisely determining glomerular filtration rate in Philippine pediatrics

    NASA Astrophysics Data System (ADS)

    Magcase, M. J. D. J.; Duyan, A. Q.; Carpio, J.; Carbonell, C. A.; Trono, J. D.

    2015-06-01

    The objective of this study is to validate the Inoue method so that it would be the preferential choice in determining glomerular filtration rate (GFR) in Philippine pediatrics. The study consisted of 36 patients ranging from ages 2 months to 19 years old. The subjects used were those who were previously subjected to in-vitro method. The scintigrams of the invitro method was obtained and processed for split percentage uptake and for parameters needed to obtain Inoue GFR. The result of this paper correlates the Inoue GFR and In-vitro method (r = 0.926). Thus, Inoue method is a viable, simple, and practical technique in determining GFR in pediatric patients.

  4. Determination of and compensation for wafer bow and warp in a scanning electron microscope requiring precise feature locating and variable tilt

    NASA Astrophysics Data System (ADS)

    Holmes, Duane C.

    1990-06-01

    Precise and accurate feature positioning in SEMs is becoming more critical. Moving the stage to a predetermined location must be done with accuracy and precision that put the feature ofinterest in the field ofview at a magnification high enough to detect orrecognize the same feature. Ifthis is notdone, some sort ofsearch, either automatic ormanual must be performed. This may not only be bothersome, but detrimental to inspection or measurement throughput performance. Ultra precise stages - for example, those using laser interferometers or linear encoders - are capable of positioning precisions, if not accuracies, to 0. 1 micron. In both optical and SEM systems where inspection is normal to the plane ofthe waler(cailed zero tilt), precise locating of features is possible without serious attention being paid to the bow or warp of a wafer. From the SEMI Standards Manuals, it is seen that a 200 mm wafer may have up to 65 microns of bow. In optical lithography tools and optical inspection or measurement systems, a vacuum chuck may alter or reduce the bow. However, in the vacuum chamber of the SEM this technique does not work. The bow or warp remains. The problem occurs in going to a particular numerical address whenthe waferis tilted, ifthat numerical address was determined at some different tilt -themost probable, of course, being zero iilt. Tilting of the wafer will cause the initially observed feature to move through an arc of "unknown" extent (unknown because it is a function of the bow and the bow is not known at that point). A 60 degree tilt of awafer with 40 microns of bow can cause about 35 microns oflaten.l displacement of a feature from where it would be expected for a wafer with no bow. The effect of this displacement on detectability is discussed. Actual displacement measurements on a 125 mm wafer ait plotted. These plots are compared with those derived from measurements made by optical and SEM systems specially set up to measure bow magnitudes. Bow

  5. New Method for Determining Isotopic Values of Glutamic Acid and Phenylalanine for Estimation of Precise Trophic Position in Food Web Studies

    NASA Astrophysics Data System (ADS)

    Kamath, T.; Broek, T.; McCarthy, M.

    2012-12-01

    Compound Specific Isotope Analysis of Amino Acids (CSI-AA) has emerged as a highly precise new method of determining trophic levels of both aquatic and terrestrial organisms. Multiple studies have now shown that δ15N values for glutamic acid (Glu) and phenylalanine (Phe) can be coupled to provide extremely precise estimates of trophic position in diverse food web studies. The standard gas chromatography—isotope ratio mass spectrometer (GC-IRMS) approach is presently limited to a select number of labs since necessary equipment is both expensive and not widely accessible. Furthermore, typical GC-IRMS δ15N precision (±1‰) is significantly lower than usual bulk δ15N values (±0.1‰), thus presenting a considerable setback for precise trophic level calculations. In this study, we develop a new dual-column method to purify Glu and Phe using high performance liquid chromatography (HPLC). Phe is purified using an analytical scale reverse phase column embedded with anionic ion-pairing reagents and collected using automated fraction collection. Glu is separated from the non-polar amino acids using the same column and further purified using a hydrophilic interaction liquid chromatography (HILIC) cation and anion-exchange column and collected via automated fraction collection. Isotopic analysis of the purified AAs is then conducted on an elemental analyzer—isotope ratio mass spectrometer (EA-IRMS). As a test of this method, we present and compare the trophic position of five marine organisms—cyanobacteria, deep-sea bamboo coral, juvenile and adult white sea bass, and harbor seal, calculated using Glu and Phe δ15N values produced by both GC-IRMS and our HPLC-EA-IRMS approach. The preliminary results of this study suggest that the HPLC-EA-IRMS method is a viable alternative to GC-IRMS, which should allow accurate trophic position estimates to be made by more researchers using more readily available instrumentation.

  6. Determination of the charge radii of several light nuclei from precision, high-energy electron elastic scattering

    SciTech Connect

    Kabir, Al Amin

    2015-12-01

    Analysis of high-energy electron scattering has been used to determine the charge radii of nuclei for several decades. Recent analysis of the Lamb shift in muonic hydrogen found an r.m.s. radius significantly different than the electron scattering result. To understand this puzzle we have analyzed the "LEDEX" data for the (e, e'p) reaction. This experiment includes measurements on several light nuclei, hydrogen, deuterium, lithium, boron, and carbon. To test our ability to measure absolute cross sections, as well as our ability to extract the charge radius, we tested our technique against the extremely well-measured carbon case and found excellent agreement using the Fourier-Bessel parametrization. We then extended the procedure to boron and lithium, which show nice agreement with the latest theoretical calculations. For hydrogen, we see clearly the limits of this technique and therefore, the charge radius is determined from the traditional extrapolation to q2 = 0. We will show that there is a model dependence in extracting the charge radius of hydrogen and its unambiguous determination is very difficult with available electron-scattering measurements.

  7. Biomimetic oligosaccharide and peptide surfactant polymers designed for cardiovascular biomaterials

    NASA Astrophysics Data System (ADS)

    Ruegsegger, Mark Andrew

    A common problem associated with cardiovascular devices is surface induced thrombosis initiated by the rapid, non-specific adsorption of plasma proteins onto the biomaterial surface. Control of the initial protein adsorption is crucial to achieve the desired longevity of the implanted biomaterial. The cell membrane glycocalyx acts as a non-thrombogenic interface through passive (dense oligosaccharide structures) and active (ligand/receptor interactions) mechanisms. This thesis is designed to investigate biomimicry of the cell glycocalyx to minimize non-specific protein adsorption and promote specific ligand/receptor interactions. Biomimetic macromolecules were designed through the molecular-scale engineering of polymer surfactants, utilizing a poly(vinyl amine) (PVAm) backbone to which hydrophilic (dextran, maltose, peptide) and hydrophobic alkyl (hexanoyl or hexanal) chains are simultaneously attached. The structure was controlled through the molar feed ratio of hydrophobic-to-hydrophilic groups, which also provided control of the solution and surface-active properties. To mimic passive properties, a series of oligomaltose surfactants were synthesized with increasing saccharide length (n = 2, 7, 15 where n is number of glucose units) to investigate the effect of coating height on protein adsorption. The surfactants were characterized by infra red (IR) and nuclear magnetic resonance (NMR) spectroscopies for structural properties and atomic force microscopy (AFM) and contact angle goniometry for surface activity. Protein adsorption under dynamic flow (5 dyn/cm2) was reduced by 85%--95% over the bare hydrophobic substrate; platelet adhesion dropped by ˜80% compared to glass. Peptide ligands were incorporated into the oligosaccharide surfactant to promote functional activity of the passive coating. The surfactants were synthesized to contain 0%, 25%, 50%, 75%, and 100% peptide ligand density and were stable on hydrophobic surfaces. The peptide surface density was

  8. Large-scale production of highly enriched 28Si for the precise determination of the Avogadro constant

    NASA Astrophysics Data System (ADS)

    Becker, P.; Schiel, D.; Pohl, H.-J.; Kaliteevski, A. K.; Godisov, O. N.; Churbanov, M. F.; Devyatykh, G. G.; Gusev, A. V.; Bulanov, A. D.; Adamchik, S. A.; Gavva, V. A.; Kovalev, I. D.; Abrosimov, N. V.; Hallmann-Seiffert, B.; Riemann, H.; Valkiers, S.; Taylor, P.; DeBièvre, P.; Dianov, E. M.

    2006-07-01

    An attempt is described to replace the present definition of the kilogram with the mass of a certain number of silicon atoms. A prerequisite for this is that the Avogadro constant, NA, is determined with a relative uncertainty of better than 2 × 10-8. For the determination, silicon crystals are used. However, the difficulty arising thereby is the measurement of the average molar mass of natural Si. Consequently, a worldwide collaboration has been launched to produce approximately a 5 kg 28Si single crystal with an enrichment factor greater than 99.985% and of sufficient chemical purity so that it can be used to determine NA with the targeted relative measurement uncertainty mentioned above. In the following, the first successful tests of all technological steps will be reported (enrichment of SiF4, distillation into silane and chemical purification, chemical vapour deposition of polycrystalline 28Si, floating zone growth of a dislocation-free single crystal) and new equipment for the production of high-purity 28Si with an enrichment of not less than 99.99% will be described. All steps are well defined by a Technical Road Map (TRM28) and all key results are measured by new mass spectrometric, IR spectroscopic and other chemical and physical methods, such as Hall effect, photoluminescence, laser scattering and x-ray topographic methods (TRM for Analytical Monitoring and Certification, TRM28-AMC). The initial enrichment of the gas is >0.999 95 and the depletion during the entire process is <0.000 05. The isotopic homogeneity is checked by natural Si crystal growth and does, in the enriched sphere, not exceed 5 × 10-10, relatively. The C content of the final material is less than 1015 atoms cm-3 and the specific resistance is 400-1000 Ω cm.

  9. Historical aspects of human milk oligosaccharides.

    PubMed

    Kunz, Clemens

    2012-05-01

    This review focuses on important observations regarding infant health around 1900 when breastfeeding was not considered a matter of importance. The discovery of lactobacilli and bifidobacteria and their relevance for health and disease was an important milestone leading to a decrease in infant mortality in the first year of life. At the same time, pediatricians realized that the fecal composition of breast-fed and bottle-fed infants differed. Observations indicated that this difference is linked to milk composition, particularly due to the milk carbohydrate fraction. Circa 1930, a human milk carbohydrate fraction called gynolactose was identified. This was the starting point of research on human milk oligosaccharides (HMO). In the following years, the first HMO were identified and their functions investigated. Studies after 1950 focused on the identification of various HMO as the bifidus factor in human milk. In the following 30 years, a tremendous amount of research was done with regard to the characterization of individual HMO and HMO patterns in milk. In this short introduction to the history of HMO research, which ends circa 1980, some outstanding scientists in pediatrics and chemistry and their pioneering contributions to research in the field of HMO are presented.

  10. Thermophoresis of cyclic oligosaccharides in polar solvents.

    PubMed

    Eguchi, Kazuya; Niether, Doreen; Wiegand, Simone; Kita, Rio

    2016-09-01

    Cyclodextrins are cyclic oligosaccharides which are interesting as drug delivery systems, because they can be used as containers for pharmaceutical substances. We studied the Ludwig-Soret effect of [Formula: see text]-, [Formula: see text]-, [Formula: see text]- and methyl-[Formula: see text]-cyclodextrin in water and formamide by infrared thermal diffusion forced Rayleigh scattering (IR-TDFRS). In water the Soret coefficient, S T, of [Formula: see text]-, [Formula: see text]- and [Formula: see text]-cyclodextrin increases with increasing temperature and shows a sign change from negative to positive around T = 35 (°) C, while S T of methyl-[Formula: see text]-cyclodextrin is positive in the entire investigated temperature. In formamide S T-values of all cyclodextrins coincide and show a slight decrease with temperature. We discuss the obtained results and relate the S T-values to the different hydrogen bonding capabilities of the cyclodextrins and the used solvents. It turns out that the change of S T with temperature correlates with the partition coefficient, logP, which indicates that more hydrophilic substances show a more pronounced temperature sensitivity of S T. Additionally we obtained a surprising result measuring the refractive index contrast factor with temperature, [Formula: see text] of cyclodextrins in formamide, which might be explained by a complex formation between cyclodextrins and formamide.

  11. Historical Aspects of Human Milk Oligosaccharides1234

    PubMed Central

    Kunz, Clemens

    2012-01-01

    This review focuses on important observations regarding infant health around 1900 when breastfeeding was not considered a matter of importance. The discovery of lactobacilli and bifidobacteria and their relevance for health and disease was an important milestone leading to a decrease in infant mortality in the first year of life. At the same time, pediatricians realized that the fecal composition of breast-fed and bottle-fed infants differed. Observations indicated that this difference is linked to milk composition, particularly due to the milk carbohydrate fraction. Circa 1930, a human milk carbohydrate fraction called gynolactose was identified. This was the starting point of research on human milk oligosaccharides (HMO). In the following years, the first HMO were identified and their functions investigated. Studies after 1950 focused on the identification of various HMO as the bifidus factor in human milk. In the following 30 years, a tremendous amount of research was done with regard to the characterization of individual HMO and HMO patterns in milk. In this short introduction to the history of HMO research, which ends circa 1980, some outstanding scientists in pediatrics and chemistry and their pioneering contributions to research in the field of HMO are presented. PMID:22585922

  12. Milk Oligosaccharides and Metabolism in Infants12

    PubMed Central

    Rudloff, Silvia; Kunz, Clemens

    2012-01-01

    Since the discovery of human milk oligosaccharides (HMO) >60 y ago, research has faced major challenges including (i) the development of methods to identify and characterize these components, (ii) the need to use HMO fractions for functional studies because single HMO were not available, (iii) the uncertainty of the purity of HMO fractions that were often “contaminated” by remainders of lactose, proteins, or glycoproteins, and (iv) the low availability of large quantities of a single HMO for animal and human studies. In the past 10 years, there has been tremendous progress in all of these areas, particularly in the development of methods for detailed structural analysis in extremely low milk volumes. The greatest success, however, is that biotechnological means are available today to produce large amounts even of a single HMO in a purity that allows human studies to be performed in the future. In this review, we summarize the current knowledge about the metabolic aspects of HMO in infants starting with the first studies by Lundblad and co-workers in the early 1980s. After discussing newer observations in recent years, the review closes with a perspective on some important questions regarding metabolic and functional aspects of HMO. PMID:22585918

  13. Precision metrology.

    PubMed

    Jiang, X; Whitehouse, D J

    2012-08-28

    This article is a summary of the Satellite Meeting, which followed on from the Discussion Meeting at the Royal Society on 'Ultra-precision engineering: from physics to manufacture', held at the Kavli Royal Society International Centre, Chicheley Hall, Buckinghamshire, UK. The meeting was restricted to 18 invited experts in various aspects of precision metrology from academics from the UK and Sweden, Government Institutes from the UK and Germany and global aerospace industries. It examined and identified metrology problem areas that are, or may be, limiting future developments in precision engineering and, in particular, metrology. The Satellite Meeting was intended to produce a vision that will inspire academia and industry to address the solutions of those open-ended problems identified. The discussion covered three areas, namely the function of engineering parts, their measurement and their manufacture, as well as their interactions.

  14. Application of scanning angle Raman spectroscopy for determining the location of buried polymer interfaces with tens of nanometer precision

    DOE PAGES

    Damin, Craig A.; Nguyen, Vy H. T.; Niyibizi, Auguste S.; ...

    2015-02-11

    In this study, near-infrared scanning angle (SA) Raman spectroscopy was utilized to determine the interface location in bilayer films (a stack of two polymer layers) of polystyrene (PS) and polycarbonate (PC). Finite-difference-time-domain (FDTD) calculations of the sum square electric field (SSEF) for films with total bilayer thicknesses of 1200–3600 nm were used to construct models for simultaneously measuring the film thickness and the location of the buried interface between the PS and PC layers. Samples with total thicknesses of 1320, 1890, 2300, and 2750 nm and varying PS/PC interface locations were analyzed using SA Raman spectroscopy. Comparing SA Raman spectroscopymore » and optical profilometry measurements, the average percent difference in the total bilayer thickness was 2.0% for films less than ~2300 nm thick. The average percent difference in the thickness of the PS layer, which reflects the interface location, was 2.5% when the PS layer was less than ~1800 nm. SA Raman spectroscopy has been shown to be a viable, non-destructive method capable of determining the total bilayer thickness and buried interface location for bilayer samples consisting of thin polymer films with comparable indices of refraction.« less

  15. Application of scanning angle Raman spectroscopy for determining the location of buried polymer interfaces with tens of nanometer precision

    SciTech Connect

    Damin, Craig A.; Nguyen, Vy H. T.; Niyibizi, Auguste S.; Smith, Emily A.

    2015-02-11

    In this study, near-infrared scanning angle (SA) Raman spectroscopy was utilized to determine the interface location in bilayer films (a stack of two polymer layers) of polystyrene (PS) and polycarbonate (PC). Finite-difference-time-domain (FDTD) calculations of the sum square electric field (SSEF) for films with total bilayer thicknesses of 1200–3600 nm were used to construct models for simultaneously measuring the film thickness and the location of the buried interface between the PS and PC layers. Samples with total thicknesses of 1320, 1890, 2300, and 2750 nm and varying PS/PC interface locations were analyzed using SA Raman spectroscopy. Comparing SA Raman spectroscopy and optical profilometry measurements, the average percent difference in the total bilayer thickness was 2.0% for films less than ~2300 nm thick. The average percent difference in the thickness of the PS layer, which reflects the interface location, was 2.5% when the PS layer was less than ~1800 nm. SA Raman spectroscopy has been shown to be a viable, non-destructive method capable of determining the total bilayer thickness and buried interface location for bilayer samples consisting of thin polymer films with comparable indices of refraction.

  16. Application of scanning angle Raman spectroscopy for determining the location of buried polymer interfaces with tens of nanometer precision

    DOE PAGES

    Damin, Craig A.; Nguyen, Vy H. T.; Niyibizi, Auguste S.; ...

    2015-02-11

    Near-infrared scanning angle (SA) Raman spectroscopy was utilized to determine the interface location in bilayer films (a stack of two polymer layers) of polystyrene (PS) and polycarbonate (PC). Finite-difference-time-domain (FDTD) calculations of the sum square electric field (SSEF) for films with total bilayer thicknesses of 1200–3600 nm were used to construct models for simultaneously measuring the film thickness and the location of the buried interface between the PS and PC layers. Samples with total thicknesses of 1320, 1890, 2300, and 2750 nm and varying PS/PC interface locations were analyzed using SA Raman spectroscopy. Comparing SA Raman spectroscopy and optical profilometrymore » measurements, the average percent difference in the total bilayer thickness was 2.0% for films less than ~2300 nm thick. The average percent difference in the thickness of the PS layer, which reflects the interface location, was 2.5% when the PS layer was less than ~1800 nm. The SA Raman spectroscopy has been shown to be a viable, non-destructive method capable of determining the total bilayer thickness and buried interface location for bilayer samples consisting of thin polymer films with comparable indices of refraction.« less

  17. Application of scanning angle Raman spectroscopy for determining the location of buried polymer interfaces with tens of nanometer precision

    SciTech Connect

    Damin, Craig A.; Nguyen, Vy H. T.; Niyibizi, Auguste S.; Smith, Emily A.

    2015-02-11

    Near-infrared scanning angle (SA) Raman spectroscopy was utilized to determine the interface location in bilayer films (a stack of two polymer layers) of polystyrene (PS) and polycarbonate (PC). Finite-difference-time-domain (FDTD) calculations of the sum square electric field (SSEF) for films with total bilayer thicknesses of 1200–3600 nm were used to construct models for simultaneously measuring the film thickness and the location of the buried interface between the PS and PC layers. Samples with total thicknesses of 1320, 1890, 2300, and 2750 nm and varying PS/PC interface locations were analyzed using SA Raman spectroscopy. Comparing SA Raman spectroscopy and optical profilometry measurements, the average percent difference in the total bilayer thickness was 2.0% for films less than ~2300 nm thick. The average percent difference in the thickness of the PS layer, which reflects the interface location, was 2.5% when the PS layer was less than ~1800 nm. The SA Raman spectroscopy has been shown to be a viable, non-destructive method capable of determining the total bilayer thickness and buried interface location for bilayer samples consisting of thin polymer films with comparable indices of refraction.

  18. Precise leveling determination of surface uplift patterns at the New Hydraulic Fracturing Facility, Oak Ridge National Laboratory

    SciTech Connect

    Haase, C.S.; Stow, S.H.

    1988-05-01

    Surface uplift patterns were determined for five grout injections at the New Hydrofracture Facility (NHF) during the period July 1983 through January 1984. The uplift patterns are complex. In plan view, they are elliptical to almost circular and exhibit varying degrees of cross-sectional asymmetry with one side steeper than the other. The long axis of the ellipse is more or less parallel to geological strike. The uplift patterns vary in size, shape and asymmetry from injection to injection. The region of maximum uplift is typically offset with respect to the injection point, suggesting that most hydrofracture injections dip to the south-southeast. Approximately 40 to 60% of the uplift measured 5 days after an injection subsided within 30 to 45 days. In one case, all of the uplift subsided within 70 days of injection. Modeling of the uplift patterns by simple models, based on homogeneous, isotropic subsurface conditions, suggests that hydrofractures produced by the injections are either horizontal or have shallow dips to the south-southeast. Such orientations are consistent with the hydrofracture orientations determined by gamma-ray logging in observation wells surrounding the NHF site. 19 refs., 17 figs., 1 tab.

  19. Rapid and precise coulometric determination and separation of redox inert ions based on electrolysis for ion transfer at the aqueous|organic solution interface.

    PubMed

    Kihara, Sorin; Kasuno, Megumi

    2011-01-01

    Flow systems for precise and accurate coulometric determinations of ions that were developed on the basis of electrolytic ion transfer at the aqueous|organic solution (W|O) interface are reviewed. The electrolysis cell in the system is composed of a porous poly(tetrafluoroethylene) tube (1.0 mm inner diameter), a metal wire (0.8 mm diameter) inserted into the tube, O into which the tube is immersed, a reference electrode in O and a platinum wire counter electrode in O. The electrolysis is carried out by forcing W containing a species of interest to flow through the narrow gap between the tube and the metal wire. The coulometric determination can be performed with an efficiency of more than 99% and a precision of better than 0.2% based on the ion transfer under an optimum condition, even if the ion is redox inert such as Na(+), K(+), Mg(2+), Ca(2+), ClO(4)(-), picrate or alkylsulfonates. The system can be applied to selective electrolytic solvent extraction of ions.

  20. The precision of wet atmospheric deposition data from national atmospheric deposition program/national trends network sites determined with collocated samplers

    USGS Publications Warehouse

    Nilles, M.A.; Gordon, J.D.; Schroder, L.J.

    1994-01-01

    A collocated, wet-deposition sampler program has been operated since October 1988 by the U.S. Geological Survey to estimate the overall sampling precision of wet atmospheric deposition data collected at selected sites in the National Atmospheric Deposition Program and National Trends Network (NADP/NTN). A duplicate set of wet-deposition sampling instruments was installed adjacent to existing sampling instruments at four different NADP/NTN sites for each year of the study. Wet-deposition samples from collocated sites were collected and analysed using standard NADP/NTN procedures. Laboratory analyses included determinations of pH, specific conductance, and concentrations of major cations and anions. The estimates of precision included all variability in the data-collection system, from the point of sample collection through storage in the NADP/NTN database. Sampling precision was determined from the absolute value of differences in the analytical results for the paired samples in terms of median relative and absolute difference. The median relative difference for Mg2+, Na+, K+ and NH4+ concentration and deposition was quite variable between sites and exceeded 10% at most sites. Relative error for analytes whose concentrations typically approached laboratory method detection limits were greater than for analytes that did not typically approach detection limits. The median relative difference for SO42- and NO3- concentration, specific conductance, and sample volume at all sites was less than 7%. Precision for H+ concentration and deposition ranged from less than 10% at sites with typically high levels of H+ concentration to greater than 30% at sites with low H+ concentration. Median difference for analyte concentration and deposition was typically 1.5-2-times greater for samples collected during the winter than during other seasons at two northern sites. Likewise, the median relative difference in sample volume for winter samples was more than double the annual median

  1. Determining neutrino mass hierarchy by precise measurements of two delta m**2 in electron-neutrino and muon-neutrino disappearance experiments

    SciTech Connect

    Minakata, H.; Nunokawa, H.; Parke, Stephen J.; Zukanovich Funchal, R.; /Sao Paulo U.

    2006-09-01

    In this talk, the authors discuss the possibility of determining the neutrino mass hierarchy by comparing the two effective atmospheric neutrino mass squared differences measured, respectively, in electron, and in muon neutrino disappearance oscillation experiments. if the former, is larger (smaller) than the latter, the mass hierarchy is of normal (inverted) type. They consider two very high precision (a few per mil) measurements of such mass squared differences by the phase II of the T2K (Tokai-to-Kamioka) experiment and by the novel Moessbauer enhanced resonant {bar {nu}}{sub e} absorption technique. Under optimistic assumptions for the systematic errors of both measurements, they determine the region of sensitivities where the mass hierarchy can be distinguished. Due to the tight space limitation, they present only the general idea and show a few most important plots.

  2. In vitro fermentation characteristics of selected oligosaccharides by swine fecal microflora.

    PubMed

    Smiricky-Tjardes, M R; Flickinger, E A; Grieshop, C M; Bauer, L L; Murphy, M R; Fahey, G C

    2003-10-01

    The objective of this study was to quantify the fermentation characteristics of oligosaccharides present in feed ingredients or isolated for dietary supplementation. Substrates studied included short-chain fructooligosaccharides, medium-chain fructooligosaccharides, long-chain fructooligosaccharides, raffinose, stachyose, soy solubles, granular and liquid forms of transgalactooligosaccharides, glucooligosaccharides, mannanoligosaccharides, and xylooligosaccharides. Three healthy pigs that had never received antibiotics served as sources of fecal inoculum. Each substrate was fermented in vitro; samples were taken at 0, 2, 4, 8, and 12 h, and pH change and short-chain fatty acid (SCFA) and gas production determined. Gas production at 12 h did not differ (P > 0.05) among all fructooligosaccharides, transgalactooligosaccharides, soy solubles, and xylooligosaccharides. Raffinose, stachyose, and raffinose + stachyose fermentation resulted in the greatest (P < 0.05) gas production at 12 h of all substrates tested. The rate of gas production was greatest (P < 0.05) for stachyose and least (P < 0.05) for glucooligosaccharides and mannanoligosaccharides. Substrate did not affect (P > 0.05) time to attain maximal rate of gas production. The pH at 12 h for all fructooligosaccharides and xylooligosaccharides did not differ (P > 0.05). The pH values at 12 h for raffinose, stachyose, and raffinose + stachyose were highest (P < 0.05) compared with all other substrates. Total SCFA production at 12 h was similar for all fructooligosaccharides and transgalactooligosaccharides, glucooligosaccharides, and soy solubles. Total SCFA production was greatest (P < 0.05) for xylooligosaccharides, stachyose, and raffinose + stachyose, and least (P < 0.05) for mannanoligosaccharides and raffinose. Stachyose fermentation resulted in the greatest (P < 0.05) rate and earliest time to attain maximal rate of SCFA production. All oligosaccharides studied were readily fermentable but varied in amount

  3. Characterization of N-linked oligosaccharides bearing sialyl lewis x moieties on an alternatively glycosylated form of soluble complement receptor type 1 (sCR1).

    PubMed

    Picard, M D; Pettey, C L; Marsh, H C; Thomas, L J

    2000-02-01

    We sought to produce a complement inhibitory protein possessing oligosaccharides specifically modified to contain the sialyl Lewis x (sLe(x)) moiety. This modified glycoprotein could combine anti-complement activity with the ability to inhibit selectin-mediated interactions and concentrate this activity to sites of activated endothelium where selectins are upregulated. Soluble complement receptor type 1 (sCR1), previously shown to be effective in inhibiting the complement cascade, was produced in a cell line capable of adding fucose to N-linked oligosaccharides in the alpha1-3 linkage, which is necessary for sLe(x) glycosylation. The glycoprotein purified from these cells was designated sCR1sLe(x), and may prove to be more effective than sCR1 in some clinical applications. Detailed analysis and characterization of sCR1sLe(x) was performed to confirm that the N-linked oligosaccharides possessed sLe(x) moieties and also to determine the extent of sLe(x) glycosylation. The glycoproteins were characterized by oligosaccharide profiling, sequencing, linkage analysis and quantified by differential enzymic digestion, using fluorophore-assisted carbohydrate electrophoresis. The major glycans were identified as biantennary oligosaccharides (including sialylated and non-core fucosylated glycans). The linkages of sialic acid and the branched fucose were analysed by digestion with linkage-specific enzymes and subsequent separation by electrophoresis. All data were consistent with the presence of sLe(x) moieties on the N-linked oligosaccharides of sCR1sLe(x). sCR1sLe(x) is a prime example of a recombinant protein expressed with oligosaccharides engineered for a specific biological function, and produced using a commercially viable method.

  4. Andes virus associated with hantavirus pulmonary syndrome in northern Argentina and determination of the precise site of infection.

    PubMed

    Gonzalez Della Valle, M; Edelstein, A; Miguel, S; Martinez, V; Cortez, J; Cacace, M L; Jurgelenas, G; Sosa Estani, S; Padula, P

    2002-06-01

    Hantavirus pulmonary syndrome (HPS) has been documented in the Salta and Jujuy provinces of northern Argentina since 1991 and 1997, respectively, accounting for almost 50% of the cases of HPS reported in this country. Andes (AND) virus, specifically the AND virus Nort lineage, was previously associated with human disease in this region. Genetic analysis of viral medium RNA segments obtained from 18 HPS cases showed the existence of three AND virus Nort sublineages co-circulating in these two provinces. They showed a nucleotide sequence diversity of up to 11.1% between the sublineages. The putative site of infection of one of these cases (Sal3/97) was determined. A 100% nucleotide sequence identity was observed between the viral sequence found in patient Sal3/97 and in two virus-positive Oligoryzomys chacoensis captured in the same place where the case lived and worked. These results indicated the putative site of infection and identified this rodent species as the source of infection.

  5. Precise Orbit Determination for GEOSAT Follow-On Using Satellite Laser Ranging Data and Intermission Altimeter Crossovers

    NASA Technical Reports Server (NTRS)

    Lemoine, F. G.; Rowlands, D. D.; Luthcke, S. B.; Zelensky, N. P.; Chinn, D. S.; Pavlis, D. E.; Marr, G. C.

    2001-01-01

    The U.S. Navy's GEOSAT Follow-On Spacecraft was launched on February 10, 1998 and the primary objective of the mission was to map the oceans using a radar altimeter. Following an extensive set of calibration campaigns in 1999 and 2000, the US Navy formally accepted delivery of the satellite on November 29, 2000. The spacecraft is tracked by satellite laser ranging (SLR) and Doppler (Tranet-style) beacons. Although a limited amount of GPS data were obtained, the primary mode of tracking remains satellite laser ranging. In this paper, we report on progress in orbit determination for GFO using GFO/GFO and TOPEX/GFO altimeter crossovers. We have tuned the nonconservative force model for GFO and the gravity model using SLR, Doppler and altimeter crossover data spanning over one year. Preliminary results show that the predicted radial orbit error from the gravity field covariance to 70x70 on GEOSAT was reduced from 2.6 cm in EGM96 to 1.9 cm with the addition of only five months of the GFO SLR and GFO/GFO crossover data. Further progress is possible with the addition of more data, particularly the TOPEX/GFO crossovers. We will evaluate the tuned GFO gravity model (a derivative of EGM96) using altimeter data from the GEOSAT mission. In January 2000, a limited quantity of GPS data were obtained. We will use these GPS data in conjunction with the SLR and altimeter crossover data obtained over the same time span to compute quasi-reduced dynamic orbits which will also aid in the evaluation of the tuned GFO geopotential model.

  6. Neutral and Acidic Oligosaccharides Supplementation Does Not Increase the Vaccine Antibody Response in Preterm Infants in a Randomized Clinical Trial

    PubMed Central

    van den Berg, Jolice P.; Westerbeek, Elisabeth A. M.; van der Klis, Fiona R. M.; Berbers, Guy A. M.; Lafeber, Harrie N.; van Elburg, Ruurd M.

    2013-01-01

    Background In preterm infants, a decreased immunological response and lower serological effectiveness are observed after immunizations due to ineffectiveness of both humoral and cellular immune mechanisms. Objective To determine the effect of 80% neutral oligosaccharides [small-chain galacto-oligosaccharides/long-chain fructo-oligosaccharides (scGOS/lcFOS)] in combination with 20% pectin-derived acidic oligosaccharides (pAOS) on antibody concentrations after DTaP-IPV-Hib immunization in preterm infants. Design In this randomized clinical trial, preterm infants with gestational age <32 weeks and/or birth weight <1500 g received enteral supplementation with scGOS/lcFOS/pAOS or placebo (maltodextrin) between days 3 and 30 of life. Blood samples were collected at 5 and 12 months of age. Results In total, 113 infants were included. Baseline and nutritional characteristics were not different in both groups. Geometric mean titers were not different after prebiotic supplementation at 5 months, Ptx (37/44 EU/ml), FHA (78/96 EU/ml), Prn (78/80 EU/ml), Diphtheria (0.40/0.57 IU/ml), Tetanus (0.74/0.99 IU/ml) and Hib (0.35/0.63 µg/ml), and at 12 months Ptx (55/66 EU/ml), FHA (122/119 EU/ml), Prn (116/106 Eu/ml), Diphtheria (0.88/1.11 IU/ml), Tetanus (1.64/1.79 IU/ml) and Hib (2.91/2.55 µg/ml). Conclusions Enteral supplementation of neutral (scGOS/lcFOS) and acidic oligosaccharides (pAOS) does not improve the immunization response in preterm infants. Trial Registration Controlled-Trials.com ISRCTN16211826 ISRCTN16211826 PMID:23951035

  7. High-precision determination of the isotopic composition of dissolved iron in iron depleted seawater by double spike multicollector-ICPMS.

    PubMed

    Lacan, Francois; Radic, Amandine; Labatut, Marie; Jeandel, Catherine; Poitrasson, Franck; Sarthou, Geraldine; Pradoux, Catherine; Chmeleff, Jerome; Freydier, Remi

    2010-09-01

    This work demonstrates the feasibility of the measurement of the isotopic composition of dissolved iron in seawater for an iron concentration range, 0.05-1 nmol L(-1), allowing measurements in most oceanic waters, including Fe depleted waters of high nutrient low chlorophyll areas. It presents a detailed description of our previously published protocol, with significant improvements on detection limit and blank contribution. Iron is preconcentrated using a nitriloacetic acid superflow resin and purified using an AG 1-x4 anion exchange resin. The isotopic ratios are measured with a multicollector-inductively coupled plasma mass spectrometer (MC-ICPMS) Neptune, coupled with a desolvator (Aridus II or Apex-Q), using a (57)Fe-(58)Fe double spike mass bias correction. A Monte Carlo test shows that optimum precision is obtained for a double spike composed of approximately 50% (57)Fe and 50% (58)Fe and a sample to double spike quantity ratio of approximately 1. Total procedural yield is 91 +/- 25% (2SD, n = 55) for sample sizes from 20 to 2 L. The procedural blank ranges from 1.4 to 1.1 ng, for sample sizes ranging from 20 to 2 L, respectively, which, converted into Fe concentrations, corresponds to blank contributions of 0.001 and 0.010 nmol L(-1), respectively. Measurement precision determined from replicate measurements of seawater samples and standard solutions is 0.08 per thousand (delta(56)Fe, 2SD). The precision is sufficient to clearly detect and quantify isotopic variations in the oceans, which so far have been observed to span 2.5 per thousand and thus opens new perspectives to elucidate the oceanic iron cycle.

  8. Precise determination of the f0(500) and f0(980) parameters in dispersive analysis of the ππ data

    NASA Astrophysics Data System (ADS)

    Kamiński, Robert; Garcia-Martin, R.; Pelaez, J. R.; Ruiz de Elvira, J.

    2013-01-01

    Use of the new and precise dispersive equations with imposed crossing symmetry condition to solve the long-standing puzzle in the parameters of the f0(500), as well as the f0(980) is presented. This puzzle is finally being settled thanks to analyzes carried out during the last years [J. Beringer et al. (Particle Data Group), Phys. Rev. D86, (2012) 010001]. In this report we show how our very recent dispersive data analysis allowed for a precise and model independent determination of the amplitudes for the S, P, D and F waves [R. Garcia-Martin, R. Kaminski, J. R. Pelaez, J. Ruiz de Elvira and F.J. Yndurain, Phys. Rev. D83, (2011) 074004; R. Garcia-Martin, R. Kamiński, J.R. Pelaez and J. Ruiz de Elvira, Phys. Rev. Lett. 107, (2011) 072001; R. Kamiński, Phys. Rev. D83, (2011) 076008]. Especially we present that the analytic continuation of once subtracted dispersion relations for the S 0 wave to the complex energy plane leads to very precise results for the f0(500) pole: √{s}=457-13+14-i279-7+11 MeV and for the f0(980) pole: √{s}=996±7-i25-6+10 MeV. We also mention on first (or one of the first) practical application of presented dispersion relations in refitting and in significant improving of the ππ S-wave amplitudes below 1000 MeV.

  9. Optimization of Oligosaccharide Synthesis from Cellobiose by Dextransucrase

    NASA Astrophysics Data System (ADS)

    Kim, Misook; Day, Donal F.

    There is a growing market for oligosaccharides as sweeteners, prebiotics, anticariogenic compounds, and immunostimulating agents in both food and pharmaceutical industries. Interest in novel carbohydrate-based products has grown because of their reduced toxicity and low immune response. Cellobiose is potentially valuable as a nondigestible sugar. The reaction of cellobiose, as an acceptor with a sucrose as a donor, catalyzed by a dextransucrase from Leuconostoc mesenteroides B-512FMCM, produced a series of cellobio-oligosaccharides. This production system was optimized using a Box-Behnken experimental design for 289 mM of sucrose and 250 mM of cellobiose and 54 U of the enzyme at pH 5.2 and 30 °C, to produce maximum yields of oligosaccharide.

  10. Novel arabinan and galactan oligosaccharides from dicotyledonous plants

    NASA Astrophysics Data System (ADS)

    Wefers, Daniel; Tyl, Catrin; Bunzel, Mirko

    2014-11-01

    Arabinans and galactans are neutral pectic side chains and an important part of the cell walls of dicotyledonous plants. To get a detailed insight into their fine structure, various oligosaccharides were isolated from quinoa, potato galactan, and sugar beet pulp after enzymatic treatment. LC-MS2 and one- and two-dimensional NMR spectroscopy were used for unambiguous structural characterization. It was demonstrated that arabinans contain β-(1→3)-linked arabinobiose as a side chain in quinoa seeds, while potato galactan was comprised of β-(1→4)-linked galactopyranoses which are interspersed with α-(1→4)-linked arabinopyranoses. Additionally, an oligosaccharide with two adjacent arabinofuranose units O2-substituted with two ferulic acid monomers was characterized. The isolated oligosaccharides gave further insight into the structures of pectic side chains and may have an impact on plant physiology and dietary fiber fermentation.

  11. Precision translator

    DOEpatents

    Reedy, Robert P.; Crawford, Daniel W.

    1984-01-01

    A precision translator for focusing a beam of light on the end of a glass fiber which includes two turning fork-like members rigidly connected to each other. These members have two prongs each with its separation adjusted by a screw, thereby adjusting the orthogonal positioning of a glass fiber attached to one of the members. This translator is made of simple parts with capability to keep adjustment even in condition of rough handling.

  12. Precision translator

    DOEpatents

    Reedy, R.P.; Crawford, D.W.

    1982-03-09

    A precision translator for focusing a beam of light on the end of a glass fiber which includes two turning fork-like members rigidly connected to each other. These members have two prongs each with its separation adjusted by a screw, thereby adjusting the orthogonal positioning of a glass fiber attached to one of the members. This translator is made of simple parts with capability to keep adjustment even in condition of rough handling.

  13. Precision and accuracy of ST-EDXRF performance for As determination comparing with ICP-MS and evaluation of As deviation in the soil media.

    PubMed

    Akbulut, Songul; Cevik, Ugur; Van, Aydın Ali; De Wael, Karolien; Van Grieken, Rene

    2014-02-01

    The present study was conducted to (i) determine the precision and accuracy of arsenic measurement in soil samples using ST-EDXRF by comparison with the results of ICP-MS analyses and (ii) identify the relationship of As concentration with soil characteristics. For the analysis of samples, inductively coupled plasma mass spectrometry (ICP-MS) and energy dispersive X-ray fluorescence spectrometry (EDXRF) were performed. According to the results found in the soil samples, the addition of HCl to HNO3, used for the digestion gave significant variations in the recovery of As. However, spectral interferences between peaks for As and Pb can affect detection limits and accuracy for XRF analysis. When comparing the XRF and ICP-MS results a correlation was observed with R(2)=0.8414. This means that using a ST-EDXRF spectrometer, it is possible to achieve accurate and precise analysis by the calibration of certified reference materials and choosing an appropriate secondary target. On the other hand, with regard to soil characteristics analyses, the study highlighted that As is mostly anthropogenically enriched in the studied area.

  14. Novel strategy for herbal species classification based on UPLC-HRMS oligosaccharide profiling.

    PubMed

    Tie, Cai; Hu, Ting; Guo, Baolin; Zhang, Jinlan

    2015-01-01

    Oligosaccharides, which exist widely in herbs, present diverse important pharmacological activities. However, the complexity of oligosaccharides seriously challenges their profiling, quality control, and elucidation of activity. In this paper, a novel oligosaccharide analytical method based on a new derivatization pretreatment and ultra-performance liquid chromatography coupled with high resolution tandem mass spectrometry (UPLC-HRMS) procedure was developed to rapidly profile and identify the oligosaccharides of Epimedium. Oligosaccharides are easily derivatized by 2,4-bis(diethylamino)-6-hydrazino-1,3,5-triazine under convenient and mild conditions. Without any further purification steps, oligosaccharides were analyzed by an established UPLC-HRMS/MS method with high sensitivity, good separation efficiency and speed. Benefitting from the derivatization, the oligosaccharides generated a response in the MS two orders of magnitude higher than that of the free oligosaccharide. Oligosaccharides of 52 Epimedium samples were profiled and identified based on the high-resolution mass spectral data. A total of 66 oligosaccharide compounds detected in 52 Epimedium herbs were relatively quantified and statistically processed by principal component analysis (PCA). The 52 Epimedium herbs could be classified into different species based on their oligosaccharide composition and content. Thirteen oligosaccharide compounds demonstrated potential as markers for Epimedium species classification, and their structures were preliminarily identified using MS/MS spectra.

  15. Synthesis of sulfated oligosaccharides by cystic fibrosis trachea epithelial cells.

    PubMed

    Mendicino, J; Sangadala, S

    1999-11-01

    The mucin glycoproteins in tracheal mucus of patients with cystic fibrosis is more highly sulfated than the corresponding secretions from healthy individuals [16]. In order to further characterize these differences in sulfation and possibly also glycosylation patterns, we compared the structures of sulfated mucin oligosaccharides synthesized by continuously cultured human tracheal cells transformed by simian virus 40. The synthesis of highly sulfated oligosaccharide chains in mucins secreted by normal human epithelial and submucosal cell lines were compared with mucins formed by cystic fibrosis tracheal epithelial and submucosal cell lines. The epithelial cell lines from cystic fibrosis trachea showed a higher rate of sulfate uptake and a significantly higher rate of synthesis and sulfation of high molecular weight chains. Mucins synthesized by each cell line in the presence of 35SO4 were isolated and oligosaccharide chains were released by beta-elimination and separated by ion exchange chromatography and gel filtration. The sulfated high molecular weight chains synthesized by the cystic fibrosis cell lines were characterized by methylation analysis and sequential glycosidase digestion before and after desulfation. Carbohydrate analysis yielded Fuc, Gal and GlcNAc in a ratio of 1:2:2.2 and only one galactosaminitol residue for about every 150-200 sugar residues present. The average molecular size of oligosaccharide chains in these fractions was between 30,000-40,000 daltons. These studies show that increased sulfation of oligosaccharides in mucins synthesized by cells from cystic fibrosis trachea is accompanied by a significant increase in the extension of a basic branched structure present in many of the lower molecular weight oligosaccharides.

  16. Rates of processing of the high mannose oligosaccharide units at the three glycosylation sites of mouse thyrotropin and the two sites of free alpha-subunits

    SciTech Connect

    Miura, Y.; Perkel, V.S.; Magner, J.A.

    1988-09-01

    We have determined the structures of high mannose (Man) oligosaccharide units at individual glycosylation sites of mouse TSH. Mouse thyrotropic tumor tissue was incubated with D-(2-/sup 3/H)Man with or without (/sup 14/C)tyrosine ((/sup 14/C) Tyr) for 2, 3, or 6 h, and for a 3-h pulse followed by a 2-h chase. TSH heterodimers or free alpha-subunits were obtained from homogenates using specific antisera. After reduction and alkylation, subunits were treated with trypsin. The tryptic fragments were then loaded on a reverse phase HPLC column to separate tryptic fragments bearing labeled oligosaccharides. The N-linked oligosaccharides were released with endoglycosidase-H and analyzed by paper chromatography. Man9GlcNac2 and Man8GlcNac2 units predominated at each time point and at each specific glycosylation site, but the processing of high Man oligosaccharides differed at each glycosylation site. The processing at Asn23 of TSH beta-subunits was slower than that at Asn56 or Asn82 of alpha-subunits. The processing at Asn82 was slightly faster than that at Asn56 for both alpha-subunits of TSH heterodimers and free alpha-subunits. The present study demonstrates that the early processing of oligosaccharides differs at the individual glycosylation sites of TSH and free alpha-subunits, perhaps because of local conformational differences.

  17. High Precision Determination of the β Decay QEC Value of 11C and Implications on the Tests of the Standard Model

    NASA Astrophysics Data System (ADS)

    Gulyuz, K.; Bollen, G.; Brodeur, M.; Bryce, R. A.; Cooper, K.; Eibach, M.; Izzo, C.; Kwan, E.; Manukyan, K.; Morrissey, D. J.; Naviliat-Cuncic, O.; Redshaw, M.; Ringle, R.; Sandler, R.; Schwarz, S.; Sumithrarachchi, C. S.; Valverde, A. A.; Villari, A. C. C.

    2016-01-01

    We report the determination of the QEC value of the mirror transition of 11C by measuring the atomic masses of 11C and 11B using Penning trap mass spectrometry. More than an order of magnitude improvement in precision is achieved as compared to the 2012 Atomic Mass Evaluation (Ame2012) [Chin. Phys. C 36, 1603 (2012)]. This leads to a factor of 3 improvement in the calculated F t value. Using the new value, QEC=1981.690 (61 ) keV , the uncertainty on F t is no longer dominated by the uncertainty on the QEC value. Based on this measurement, we provide an updated estimate of the Gamow-Teller to Fermi mixing ratio and standard model values of the correlation coefficients.

  18. Precise Determination of the Strong Coupling Constant at NNLO in QCD from the Three-Jet Rate in Electron-Positron Annihilation at LEP

    SciTech Connect

    Dissertori, G.; Gehrmann-DeRidder, A.; Gehrmann, T.; Glover, E. W. N.; Heinrich, G.; Stenzel, H.

    2010-02-19

    We present the first determination of the strong coupling constant from the three-jet rate in e{sup +}e{sup -} annihilation at LEP, based on a next-to-next-to-leading-order (NNLO) perturbative QCD prediction. More precisely, we extract {alpha}{sub s}(M{sub Z}) by fitting perturbative QCD predictions at O({alpha}{sub s}{sup 3}) to data from the ALEPH experiment at LEP. Over a large range of the jet-resolution parameter y{sub cut}, this observable is characterized by small nonperturbative corrections and an excellent stability under renormalization scale variation. We find {alpha}{sub s}(M{sub Z})=0.1175+-0.0020(expt)+-0.0015(theor), which is more accurate than the values of {alpha}{sub s}(M{sub Z}) from e{sup +}e{sup -} event-shape data currently used in the world average.

  19. Inter-observer Precision and Physiologic Variability of MRI Landmarks Used to Determine Rotational Alignment in Conventional and Patient-Specific TKA

    PubMed Central

    Park, Andrew; Nam, Denis; Friedman, Michael; Duncan, Stephen; Hillen, Travis; Barrack, Robert

    2014-01-01

    Preoperative planning for patient-specific guides (PSGs) in total knee arthroplasty (TKA) requires identification of anatomic landmarks on three-dimensional imaging studies. The aim of this study was to assess the accuracy and precision with which landmarks commonly used to determine rotational alignment in TKA can be identified on magnetic resonance imaging (MRI). Two orthopaedic surgeons and two musculoskeletal radiologists independently reviewed a sequential series of 114 MRIs of arthritic knees. The magnitude of interobserver variability was high, suggesting an inherent risk of inconsistency when these landmarks are used in PSG fabrication. Additionally, there was a high degree of physiologic variation among patients, indicating that assuming standard relationships among anatomic landmarks when placing TKA components may lead to rotational malalignment relative to each patient's native anatomy. PMID:25267537

  20. Role of human milk oligosaccharides in Group B Streptococcus colonisation.

    PubMed

    Andreas, Nicholas J; Al-Khalidi, Asmaa; Jaiteh, Mustapha; Clarke, Edward; Hyde, Matthew J; Modi, Neena; Holmes, Elaine; Kampmann, Beate; Mehring Le Doare, Kirsty

    2016-08-01

    Group B Streptococcus (GBS) infection is a major cause of morbidity and mortality in infants. The major risk factor for GBS disease is maternal and subsequent infant colonisation. It is unknown whether human milk oligosaccharides (HMOs) protect against GBS colonisation. HMO production is genetically determined and linked to the Lewis antigen system. We aimed to investigate the association between HMOs and infant GBS colonisation between birth and postnatal day 90. Rectovaginal swabs were collected at delivery, as well as colostrum/breast milk, infant nasopharyngeal and rectal swabs at birth, 6 days and days 60-89 postpartum from 183 Gambian mother/infant pairs. GBS colonisation and serotypes were determined using culture and PCR. (1)H nuclear magnetic resonance spectroscopy was used to characterise the mother's Lewis status and HMO profile in breast milk. Mothers who were Lewis-positive were significantly less likely to be colonised by GBS (X (2)=12.50, P<0.001). Infants of Lewis-positive mothers were less likely GBS colonised at birth (X (2)=4.88 P=0.03) and more likely to clear colonisation between birth and days 60-89 than infants born to Lewis-negative women (P=0.05). There was no association between Secretor status and GBS colonisation. In vitro work revealed that lacto-N-difucohexaose I (LNDFHI) correlated with a reduction in the growth of GBS. Our results suggest that HMO such as LNDFHI may be a useful adjunct in reducing maternal and infant colonisation and hence invasive GBS disease. Secretor status offers utility as a stratification variable in GBS clinical trials.

  1. Distribution of core oligosaccharide types in lipopolysaccharides from Escherichia coli.

    PubMed

    Amor, K; Heinrichs, D E; Frirdich, E; Ziebell, K; Johnson, R P; Whitfield, C

    2000-03-01

    In the lipopolysaccharides of Escherichia coli there are five distinct core oligosaccharide (core OS) structures, designated K-12 and R1 to R4. The objective of this work was to determine the prevalences of these core OS types within the species. Unique sequences in the waa (core OS biosynthesis) gene operon were used to develop a PCR-based system that facilitated unequivocal determination of the core OS types in isolates of E. coli. This system was applied to the 72 isolates in the E. coli ECOR collection, a compilation of isolates that is considered to be broadly representative of the genetic diversity of the species. Fifty (69. 4%) of the ECOR isolates contained the R1 core OS, 8 (11.1%) were representatives of R2, 8 (11.1%) were R3, 2 (2.8%) were R4, and only 4 (5.6%) were K-12. R1 is the only core OS type found in all four major phylogenetic groups (A, B1, B2, and D) in the ECOR collection. Virulent extraintestinal pathogenic E. coli isolates tend to be closely related to group B2 and, to a lesser extent, group D isolates. All of the ECOR representatives from the B2 and D groups had the R1 core OS. In contrast, commensal E. coli isolates are more closely related to group A, which contains isolates representing each of the five core OS structures. R3 was the only core OS type found in 38 verotoxigenic E. coli (VTEC) isolates from humans and cattle belonging to the common enterohemorrhagic E. coli serogroups O157, O111, and O26. Although isolates from other VTEC serogroups showed more core OS diversity, the R3 type (83.1% of all VTEC isolates) was still predominant. When non-VTEC commensal isolates from cattle were analyzed, it was found that most possessed the R1 core OS type.

  2. Role of human milk oligosaccharides in Group B Streptococcus colonisation

    PubMed Central

    Andreas, Nicholas J; Al-Khalidi, Asmaa; Jaiteh, Mustapha; Clarke, Edward; Hyde, Matthew J; Modi, Neena; Holmes, Elaine; Kampmann, Beate; Mehring Le Doare, Kirsty

    2016-01-01

    Group B Streptococcus (GBS) infection is a major cause of morbidity and mortality in infants. The major risk factor for GBS disease is maternal and subsequent infant colonisation. It is unknown whether human milk oligosaccharides (HMOs) protect against GBS colonisation. HMO production is genetically determined and linked to the Lewis antigen system. We aimed to investigate the association between HMOs and infant GBS colonisation between birth and postnatal day 90. Rectovaginal swabs were collected at delivery, as well as colostrum/breast milk, infant nasopharyngeal and rectal swabs at birth, 6 days and days 60–89 postpartum from 183 Gambian mother/infant pairs. GBS colonisation and serotypes were determined using culture and PCR. 1H nuclear magnetic resonance spectroscopy was used to characterise the mother's Lewis status and HMO profile in breast milk. Mothers who were Lewis-positive were significantly less likely to be colonised by GBS (X2=12.50, P<0.001). Infants of Lewis-positive mothers were less likely GBS colonised at birth (X2=4.88 P=0.03) and more likely to clear colonisation between birth and days 60–89 than infants born to Lewis-negative women (P=0.05). There was no association between Secretor status and GBS colonisation. In vitro work revealed that lacto-N-difucohexaose I (LNDFHI) correlated with a reduction in the growth of GBS. Our results suggest that HMO such as LNDFHI may be a useful adjunct in reducing maternal and infant colonisation and hence invasive GBS disease. Secretor status offers utility as a stratification variable in GBS clinical trials. PMID:27588204

  3. Scipio: Using protein sequences to determine the precise exon/intron structures of genes and their orthologs in closely related species

    PubMed Central

    Keller, Oliver; Odronitz, Florian; Stanke, Mario; Kollmar, Martin; Waack, Stephan

    2008-01-01

    Background For many types of analyses, data about gene structure and locations of non-coding regions of genes are required. Although a vast amount of genomic sequence data is available, precise annotation of genes is lacking behind. Finding the corresponding gene of a given protein sequence by means of conventional tools is error prone, and cannot be completed without manual inspection, which is time consuming and requires considerable experience. Results Scipio is a tool based on the alignment program BLAT to determine the precise gene structure given a protein sequence and a genome sequence. It identifies intron-exon borders and splice sites and is able to cope with sequencing errors and genes spanning several contigs in genomes that have not yet been assembled to supercontigs or chromosomes. Instead of producing a set of hits with varying confidence, Scipio gives the user a coherent summary of locations on the genome that code for the query protein. The output contains information about discrepancies that may result from sequencing errors. Scipio has also successfully been used to find homologous genes in closely related species. Scipio was tested with 979 protein queries against 16 arthropod genomes (intra species search). For cross-species annotation, Scipio was used to annotate 40 genes from Homo sapiens in the primates Pongo pygmaeus abelii and Callithrix jacchus. The prediction quality of Scipio was tested in a comparative study against that of BLAT and the well established program Exonerate. Conclusion Scipio is able to precisely map a protein query onto a genome. Even in cases when there are many sequencing errors, or when incomplete genome assemblies lead to hits that stretch across multiple target sequences, it very often provides the user with the correct determination of intron-exon borders and splice sites, showing an improved prediction accuracy compared to BLAT and Exonerate. Apart from being able to find genes in the genome that encode the query

  4. A new, quick, highly sensitive ultramicro-analysis method for the identification of fructose removed from fructofuranosyl-containing gluco-oligosaccharides by ESI-CID-MS/MS.

    PubMed

    Zhang, Hong-Tao; Zhu, Li; Zhang, Shuang; Zhan, Xiao-Bei; Lin, Chi-Chung

    2014-10-29

    An efficient, highly sensitive, and ultramicroscale analytical method for the identification of fructose removed from fructofuranosyl-containing gluco-oligosaccharides, including malto-oligosyl fructofuranosides and oligomeric (1→2)-α-D-glucopyranosyl-(1→2)-β-D-fructofuranosides by ESI-CID-MS/MS has been developed with proven applications far superior to the existing method using NMR. With the established principle of diagnostic fragmentation by ESI-CID-MS/MS, the terminal saccharide (either glucose or fructose) can be readily and unambiguously determined at high sensitivity without a tedious derivatization process. Detection of the A-type fragmentation (0,4)A-h type ion, and (0,2)A type ion are useful as a diagnostic fragmentation tool to identify whether fructose terminal is removed from oligosaccharides. It will facilitate the efficient production of suitable oligosaccharide microarrays crucial for studies on carbohydrate-protein interaction in seeking functional carbohydrates.

  5. Xylo- and cello-oligosaccharide oxidation by gluco-oligosaccharide oxidase from Sarocladium strictum and variants with reduced substrate inhibition

    PubMed Central

    2013-01-01

    Background The oxidation of carbohydrates from lignocellulose can facilitate the synthesis of new biopolymers and biochemicals, and also reduce sugar metabolism by lignocellulolytic microorganisms, reserving aldonates for fermentation to biofuels. Although oxidoreductases that oxidize cellulosic hydrolysates have been well characterized, none have been reported to oxidize substituted or branched xylo-oligosaccharides. Moreover, this is the first report that identifies amino acid substitutions leading to GOOX variants with reduced substrate inhibition. Results The recombinant wild type gluco-oligosaccharide oxidase (GOOX) from the fungus Sarocladium strictum, along with variants that were generated by site-directed mutagenesis, retained the FAD cofactor, and showed high activity on cello-oligosaccharide and xylo-oligosaccharides, including substituted and branched xylo-oligosaccharides. Mass spectrometric analyses confirmed that GOOX introduces one oxygen atom to oxidized products, and 1H NMR and tandem mass spectrometry analysis confirmed that oxidation was restricted to the anomeric carbon. The A38V mutation, which is close to a predicted divalent ion-binding site in the FAD-binding domain of GOOX but 30 Å away from the active site, significantly increased the kcat and catalytic efficiency of the enzyme on all oligosaccharides. Eight amino acid substitutions were separately introduced to the substrate-binding domain of GOOX-VN (at positions Y72, E247, W351, Q353 and Q384). In all cases, the Km of the enzyme variant was higher than that of GOOX, supporting the role of corresponding residues in substrate binding. Most notably, W351A increased Km values by up to two orders of magnitude while also increasing kcat up to 3-fold on cello- and xylo-oligosaccharides and showing no substrate inhibition. Conclusions This study provides further evidence that S. strictum GOOX has broader substrate specificity than the enzyme name implies, and that substrate inhibition can be

  6. Label-Free Absolute Quantitation of Oligosaccharides Using Multiple Reaction Monitoring

    PubMed Central

    2015-01-01

    An absolute quantitation method for measuring free human milk oligosaccharides (HMOs) in milk samples was developed using multiple reaction monitoring (MRM). To obtain the best sensitivity, the instrument conditions were optimized to reduce the source and postsource fragmentation prior to the quadrupole transmission. Fragmentation spectra of HMOs using collision-induced dissociation were studied to obtain the best characteristic fragments. At least two MRM transitions were used to quantify and identify each structure in the same run. The fragment ions corresponded to the production of singly charged mono-, di-, and trisaccharide fragments. The sensitivity and accuracy of the quantitation using MRM were determined, with the detection limit in the femtomole level and the calibration range spanning over 5 orders of magnitude. Seven commercial HMO standards were used to create calibration curves and were used to determine a universal response for all HMOs. The universal response factor was used to estimate absolute amounts of other structures and the total oligosaccharide content in milk. The quantitation method was applied to 20 human milk samples to determine the variations in HMO concentrations from women classified as secretors and nonsecretors, a phenotype that can be identified by the concentration of 2′-fucosylation in their milk. PMID:24502421

  7. Chito-oligosaccharide reduces diarrhea incidence and attenuates the immune response of weaned pigs challenged with Escherichia coli K88.

    PubMed

    Liu, P; Piao, X S; Thacker, P A; Zeng, Z K; Li, P F; Wang, D; Kim, S W

    2010-12-01

    Seventy-two barrows (Landrace × Large White, initial BW of 4.9 ± 0.3 kg and 17 ± 3 d old) were used to determine if dietary chito-oligosaccharides can replace antibiotics as a means to reduce signs associated with infection in weaned pigs challenged with Escherichia coli. Pigs were assigned to 1 of 4 treatments in a randomized complete block design using 6 pens per treatment with 3 pigs per pen. The treatments consisted of pigs fed the unsupplemented corn-soybean meal diet challenged or unchallenged with E. coli K88 and pigs fed the same diet supplemented with 160 mg of chito-oligosaccharides or 100 mg of cyadox/kg and challenged with E. coli K88. On d 7, 1 group of pigs fed the unsupplemented diet, as well as all pigs fed diets containing chito-oligosaccharides or cyadox, were orally dosed with 30 mL of an alkaline broth containing E. coli K88. Another group of pigs fed the unsupplemented diet was orally dosed with 30 mL of sterilized alkaline broth. Fecal consistency was visually assessed each morning from d 7 to 14. Blood samples were collected at 0, 24, 48, and 168 h postinfection. On d 14 postchallenge, all pigs were killed to evaluate intestinal morphology and determine E. coli concentrations in the intestine. During the postchallenge period (wk 2), unsupplemented pigs challenged with E. coli had decreased (P < 0.05) BW gain, feed intake, fecal consistency, villus height, villus height:crypt depth ratio, and plasma IGF-1, and increased (P < 0.05) diarrhea incidence, E. coli counts in the intestine, plasma interleukin-1β, plasma IL-10, and IGA-positive cells in the jejunal and ileal lamina propria, compared with unchallenged pigs. Supplementation with cyadox largely mitigated these effects. Although chito-oligosaccharide reduced the incidence of diarrhea, the growth performance of E. coli-challenged pigs supplemented with chito-oligosaccharide was not better than that of unsupplemented pigs challenged with E. coli. Therefore, chito-oligosaccharide, at the

  8. Screening Substrate Properties of Microorganisms for Biosensor Detection of Oligosaccharides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oligosaccharides feature high biological activity ensuring their wide application in the biotechnology, food, and cosmetic industries. On the other hand they are considered environmental pollutants. The study outlines a biosensor approach to detect these substances which is important from above st...

  9. Production of oligosaccharides in yogurt containing bifidobacteria and yogurt cultures.

    PubMed

    Lamoureux, L; Roy, D; Gauthier, S F

    2002-05-01

    Yogurts were prepared by using yogurt cultures combined to mixed cultures of bifidobacteria (Bifidobacterium animalis, Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium infantis, and Bifidobacterium longum) and by adding a preincubation step (1.5 h at 50 degrees C) with bifidobacteria to the conventional method of manufacture in order to produce oligosaccharides. The survival of bifidobacteria was drastically affected during storage of yogurts, except for products containing B. animalis, in which viable counts remained at >10(6) cfu/g after 28 d of storage at 4 degrees C. Oligosaccharides with a degree of polymerization of 3 were produced during the preincubation step (0.31 to 0.68%), and the amount in the final products varied according to the species of bifidobacteria inoculated during the preincubation step or the concentration of bifidobacteria used as second inoculum during the fermentation process. In fact, the higher concentration of oligosaccharides measured at the end of the fermentation process (0.72%) and the 28 d-storage period (0.67%) was obtained for yogurts containing B. infantis. However, yogurts containing B. breve showed higher beta-galactosidase activities and had lower lactose concentrations after the fermentation process and the storage period than the other yogurts. The use of a mixed cultures of bifidobacteria (B. animalis, B. infantis, or B. breve) thus allows the production of yogurts in which bifidobacteria can survive in relatively high cell numbers and contain appreciable amount of oligosaccharides.

  10. Chitin oligosaccharide deacetylase from Shewanella baltica ATCC BAA-1091.

    PubMed

    Hirano, Takako; Shiraishi, Haruka; Ikejima, Masafumi; Uehara, Rie; Hakamata, Wataru; Nishio, Toshiyuki

    2017-03-01

    Chitin oligosaccharide deacetylase (COD) from bacteria that have been examined so far typically comprise two carbohydrate-binding domains (CBDs) and one polysaccharide deacetylase domain. In contrast, Shewanella baltica ATCC BAA-1091 COD (Sb-COD) has only one CBD, yet exhibits chitin-binding properties and substrate specificities similar to those of other CODs.

  11. Precise determination of the low-energy hadronic contribution to the muon g -2 from analyticity and unitarity: An improved analysis

    NASA Astrophysics Data System (ADS)

    Ananthanarayan, B.; Caprini, Irinel; Das, Diganta; Imsong, I. Sentitemsu

    2016-06-01

    The two-pion low-energy contribution to the anomalous magnetic moment of the muon, aμ≡(g -2 )μ/2 , expressed as an integral over the modulus squared of the pion electromagnetic form factor, brings a relatively large contribution to the theoretical error, since the low accuracy of experimental measurements in this region is amplified by the drastic increase of the integration kernel. We derive stringent constraints on the two-pion contribution by exploiting analyticity and unitarity of the pion electromagnetic form factor. To avoid the poor knowledge of the modulus of this function, we use instead its phase, known with high precision in the elastic region from Roy equations for pion-pion scattering via the Fermi-Watson theorem. Above the inelastic threshold we adopt a conservative integral condition on the modulus, determined from data and perturbative QCD. Additional high precision data on the modulus in the range 0.65-0.71 GeV, obtained from e+e- annihilation and τ -decay experiments, are used to improve the predictions on the modulus at lower energies by means of a parametrization-free analytic extrapolation. The results are optimal for a given input and do not depend on the unknown phase of the form factor above the inelastic threshold. The present work improves a previous analysis based on the same technique, including more experimental data and employing better statistical tools for their treatment. We obtain for the contribution to aμ from below 0.63 GeV the value (133.258 ±0.723 )×10-10 , which amounts to a reduction of the theoretical error by about 6 ×10-11 .

  12. Effect of oligosaccharides on the growth of Lactobacillus delbrueckii subsp. bulgaricus strains isolated from dairy products.

    PubMed

    Ignatova, Tseteslava; Iliev, Ilia; Kirilov, Nikolai; Vassileva, Tonka; Dalgalarrondo, Michèle; Haertlé, Thomas; Chobert, Jean-Marc; Ivanova, Iskra

    2009-10-28

    Eighteen lactic acid bacteria (LAB) strains isolated from dairy products, all identified as Lactobacillus delbrueckii subsp. bulgaricus, were tested for their ability to grow on three different oligosaccharides: fructo-oligosaccharides (FOS), gluco-oligosaccharides (GOS) and galacto-oligosaccharides (GalOS). The growth of LAB on different oligosaccharides was very different. Study of the antimicrobial activities of these LAB indicated that the system of uptake of unusual sugars influenced in a specific way the production of antimicrobial substances (bacteriocins) specific against gram-negative bacteria. The added oligosaccharides induced LAB to form end-products of a typical mixed acid fermentation. The utilization of different types of oligosaccharides may help to explain the ability of Lactobacillus strains to compete with other bacteria in the ecosystem of the human gastro-intestinal tract.

  13. High-precision (p,t) reaction measurement to determine {sup 18}Ne({alpha},p){sup 21}Na reaction rates

    SciTech Connect

    Matic, A.; Berg, A. M. van den; Harakeh, M. N.; Woertche, H. J.; Berg, G. P. A.; Couder, M.; Fisker, J. L.; Goerres, J.; LeBlanc, P.; O'Brien, S.; Wiescher, M.; Fujita, K.; Hatanaka, K.; Sakemi, Y.; Shimizu, Y.; Tameshige, Y.; Tamii, A.; Yosoi, M.; Adachi, T.; Fujita, Y.

    2009-11-15

    x-ray bursts are identified as thermonuclear explosions in the outer atmosphere of accreting neutron stars. The thermonuclear runaway is fueled by the {alpha}p process that describes a sequence of ({alpha},p) reactions triggered by the {sup 18}Ne({alpha},p){sup 21}Na breakout reaction from the hot CNO cycles. We studied the level structure of the compound nucleus {sup 22}Mg by measuring the {sup 24}Mg(p,t){sup 22}Mg reaction at the Grand Raiden spectrometer at Research Center for Nuclear Physics, Osaka. A large number of {alpha}-unbound states was identified and precise excitation energies were determined. Based on shell model and {alpha}-cluster model calculations we predict the level parameters for determining the stellar reaction rate of {sup 18}Ne({alpha},p){sup 21}Na for a wide temperature range. x-ray burst simulations have been performed to study the impact of the reaction on the x-ray burst luminosity.

  14. High-precision determination of 18O/16O ratios of silver phosphate by EA-pyrolysis-IRMS continuous flow technique.

    PubMed

    Lécuyer, Christophe; Fourel, François; Martineau, François; Amiot, Romain; Bernard, Aurélien; Daux, Valérie; Escarguel, Gilles; Morrison, John

    2007-01-01

    A high-precision, and rapid on-line method for oxygen isotope analysis of silver phosphate is presented. The technique uses high-temperature elemental analyzer (EA)-pyrolysis interfaced in continuous flow (CF) mode to an isotopic ratio mass spectrometer (IRMS). Calibration curves were generated by synthesizing silver phosphate with a 13 per thousand spread in delta(18)O values. Calibration materials were obtained by reacting dissolved potassium dihydrogen phosphate (KH(2)PO(4)) with water samples of various oxygen isotope compositions at 373 K. Validity of the method was tested by comparing the on-line results with those obtained by classical off-line sample preparation and dual inlet isotope measurement. In addition, silver phosphate precipitates were prepared from a collection of biogenic apatites with known delta(18)O values ranging from 12.8 to 29.9 per thousand (V-SMOW). Reproducibility of +/- 0.2 per thousand was obtained by the EA-Py-CF-IRMS method for sample sizes in the range 400-500 microg. Both natural and synthetic samples are remarkably well correlated with conventional (18)O/(16)O determinations. Silver phosphate is a very stable material and easy to degas and, thus, could be considered as a good candidate to become a reference material for the determination of (18)O/(16)O ratios of phosphate by high-temperature pyrolysis.

  15. Precision Muonium Spectroscopy

    NASA Astrophysics Data System (ADS)

    Jungmann, Klaus P.

    2016-09-01

    The muonium atom is the purely leptonic bound state of a positive muon and an electron. It has a lifetime of 2.2 µs. The absence of any known internal structure provides for precision experiments to test fundamental physics theories and to determine accurate values of fundamental constants. In particular ground state hyperfine structure transitions can be measured by microwave spectroscopy to deliver the muon magnetic moment. The frequency of the 1s-2s transition in the hydrogen-like atom can be determined with laser spectroscopy to obtain the muon mass. With such measurements fundamental physical interactions, in particular quantum electrodynamics, can also be tested at highest precision. The results are important input parameters for experiments on the muon magnetic anomaly. The simplicity of the atom enables further precise experiments, such as a search for muonium-antimuonium conversion for testing charged lepton number conservation and searches for possible antigravity of muons and dark matter.

  16. Selective chemical oxidation and depolymerization of switchgrass [corrected] (Panicum virgatum L.) xylan with [corrected] oligosaccharide product analysis by mass spectrometry.

    PubMed

    Bowman, Michael J; Dien, Bruce S; O'Bryan, Patricia J; Sarath, Gautam; Cotta, Michael A

    2011-04-15

    Xylan is a barrier to enzymatic hydrolysis of plant cell walls. It is well accepted that the xylan layer needs to be removed to efficiently hydrolyze cellulose; consequently, pretreatment conditions are (in part) optimized for maximal xylan depolymerization or displacement. Xylan consists of a long chain of β-1,4-linked xylose units substituted with arabinose (typically α-1,3-linked in grasses) and glucuronic acid (α-1,2-linked). Xylan has been proposed to have a structural function in plants and therefore may play a role in determining biomass reactivity to pretreatment. It has been proposed that substitutions along xylan chains are not random and, based upon studies of pericarp xylan, are organized in domains that have specific structural functions. Analysis of intact xylan is problematic because of its chain length (> degree of polymerization (d.p.) 100) and heterogeneous side groups. Traditionally, enzymatic end-point products have been characterized due to the limited products generated. Analysis of resultant arabino-xylo-oligosaccharides by mass spectrometry is complicated by the isobaric pentose sugars that primarily compose xylan. In this report, the variation in pentose ring structures was exploited for selective oxidation of the arabinofuranose primary alcohols followed by acid depolymerization to provide oligosaccharides with modified arabinose branches intact. Switchgrass samples were analyzed by hydrophilic interaction chromatography (HILIC)-liquid chromatography (LC)-mass spectrometry/mass spectrometry (MSMS) and off-line nanospray MS to demonstrate the utility of this chemistry for determination of primary hydroxyl groups on oligosaccharide structures, with potential applications for determining the sequence of arabino-xylo-oligosaccharides present in plant cell wall material.

  17. Precision medicine in cardiology.

    PubMed

    Antman, Elliott M; Loscalzo, Joseph

    2016-10-01

    The cardiovascular research and clinical communities are ideally positioned to address the epidemic of noncommunicable causes of death, as well as advance our understanding of human health and disease, through the development and implementation of precision medicine. New tools will be needed for describing the cardiovascular health status of individuals and populations, including 'omic' data, exposome and social determinants of health, the microbiome, behaviours and motivations, patient-generated data, and the array of data in electronic medical records. Cardiovascular specialists can build on their experience and use precision medicine to facilitate discovery science and improve the efficiency of clinical research, with the goal of providing more precise information to improve the health of individuals and populations. Overcoming the barriers to implementing precision medicine will require addressing a range of technical and sociopolitical issues. Health care under precision medicine will become a more integrated, dynamic system, in which patients are no longer a passive entity on whom measurements are made, but instead are central stakeholders who contribute data and participate actively in shared decision-making. Many traditionally defined diseases have common mechanisms; therefore, elimination of a siloed approach to medicine will ultimately pave the path to the creation of a universal precision medicine environment.

  18. Extraction of CO2 from air samples for isotopic analysis and limits to ultra high precision delta18O determination in CO2 gas.

    PubMed

    Werner, R A; Rothe, M; Brand, W A

    2001-01-01

    The determination of delta18O values in CO2 at a precision level of +/-0.02 per thousand (delta-notation) has always been a challenging, if not impossible, analytical task. Here, we demonstrate that beyond the usually assumed major cause of uncertainty - water contamination - there are other, hitherto underestimated sources of contamination and processes which can alter the oxygen isotope composition of CO2. Active surfaces in the preparation line with which CO2 comes into contact, as well as traces of air in the sample, can alter the apparent delta18O value both temporarily and permanently. We investigated the effects of different surface materials including electropolished stainless steel, Duran glass, gold and quartz, the latter both untreated and silanized. CO2 frozen with liquid nitrogen showed a transient alteration of the 18O/16O ratio on all surfaces tested. The time to recover from the alteration as well as the size of the alteration varied with surface type. Quartz that had been ultrasonically cleaned for several hours with high purity water (0.05 microS) exhibited the smallest effect on the measured oxygen isotopic composition of CO2 before and after freezing. However, quartz proved to be mechanically unstable with time when subjected to repeated large temperature changes during operation. After several days of operation the gas released from the freezing step contained progressively increasing trace amounts of O2 probably originating from inclusions within the quartz, which precludes the use of quartz for cryogenically trapping CO2. Stainless steel or gold proved to be suitable materials after proper pre-treatment. To ensure a high trapping efficiency of CO2 from a flow of gas, a cold trap design was chosen comprising a thin wall 1/4" outer tube and a 1/8" inner tube, made respectively from electropolished stainless steel and gold. Due to a considerable 18O specific isotope effect during the release of CO2 from the cold surface, the thawing time had to

  19. Separation of Oligosaccharides from Lotus Seeds via Medium-pressure Liquid Chromatography Coupled with ELSD and DAD

    NASA Astrophysics Data System (ADS)

    Lu, Xu; Zheng, Zhichang; Miao, Song; Li, Huang; Guo, Zebin; Zhang, Yi; Zheng, Yafeng; Zheng, Baodong; Xiao, Jianbo

    2017-03-01

    Lotus seeds were identified by the Ministry of Public Health of China as both food and medicine. One general function of lotus seeds is to improve intestinal health. However, to date, studies evaluating the relationship between bioactive compounds in lotus seeds and the physiological activity of the intestine are limited. In the present study, by using medium pressure liquid chromatography coupled with evaporative light-scattering detector and diode-array detector, five oligosaccharides were isolated and their structures were further characterized by electrospray ionization-mass spectrometry and gas chromatography-mass spectrometry. In vitro testing determined that LOS3-1 and LOS4 elicited relatively good proliferative effects on Lactobacillus delbrueckii subsp. bulgaricus. These results indicated a structure-function relationship between the physiological activity of oligosaccharides in lotus seeds and the number of probiotics applied, thus providing room for improvement of this particular feature. Intestinal probiotics may potentially become a new effective drug target for the regulation of immunity.

  20. Lactic acid bacteria fermentation of human milk oligosaccharide components, human milk oligosaccharides and galactooligosaccharides.

    PubMed

    Schwab, Clarissa; Gänzle, Michael

    2011-02-01

    Human milk contains about 7% lactose and 1% human milk oligosaccharides (HMOs) consisting of lactose with linked fucose, N-acetylglucosamine and sialic acid. In infant formula, galactooligosaccharides (GOSs) are added to replace HMOs. This study investigated the ability of six strains of lactic acid bacteria (LAB), Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus reuteri, Streptococcus thermophilus and Leuconostoc mesenteroides subsp. cremoris, to digest HMO components, defined HMOs, and GOSs. All strains grew on lactose and glucose. N-acetylglucosamine utilization varied between strains and was maximal in L. plantarum; fucose utilization was low or absent in all strains. Both hetero- and homofermentative LAB utilized N-acetylglucosamine via the Embden-Meyerhof pathway. Lactobacillus acidophilus and L. plantarum were the most versatile in hydrolysing pNP analogues and the only strains releasing mono- and disaccharides from defined HMOs. Whole cells of all six LAB hydrolysed oNP-galactoside and pNP-galactoside indicating β-galactosidase activity. High β-galactosidase activity of L. reuteri, L. fermentum, S. thermophilus and L. mesenteroides subsp. cremoris whole cells correlated to lactose and GOS hydrolysis. Hydrolysis of lactose and GOSs by heterologously expressed β-galactosidases confirmed that LAB β-galactosidases are involved in GOS digestion. In summary, the strains of LAB used were not capable of utilizing complex HMOs but metabolized HMO components and GOSs.

  1. Determination of (241)Pu by the method of disturbed radioactive equilibrium using 2πα-counting and precision gamma-spectrometry.

    PubMed

    Alekseev, I; Kuzmina, T

    2016-04-01

    A simple technique is proposed for the determination of the content of (241)Pu, which is based on disturbance of radioactive equilibrium in the genetically related (237)U←(241)Pu→(241)Am decay chain of radionuclides, with the subsequent use of 2πα-counting and precision gamma-spectroscopy for monitoring the process of restoration of that equilibrium. It has been shown that the data on dynamics of accumulation of the daughter (241)Am, which were obtained from the results of measurements of α- and γ-spectra of the samples, correspond to the estimates calculated for the chain of two genetically related radionuclides, the differences in the estimates of (241)Pu radioactivity not exceeding 2%. Combining the different methods of registration (2πα-counting, semiconductor alpha- and gamma-spectrometry) enables the proposed method to be efficiently applied both for calibration of (241)Pu-sources (from several hundreds of kBq and higher) and for radioisotopic analysis of plutonium mixtures. In doing so, there is a deep purification of (241)Pu from its daughter decay products required due to unavailability of commercial detectors that could make it possible, based only on analysis of alpha-spectra, to conduct quantitative analysis of the content of (238)Pu and (241)Am.

  2. Sensitive and precise HPLC method with back-extraction clean-up step for the determination of sildenafil in rat plasma and its application to a pharmacokinetic study.

    PubMed

    Strach, Beata; Wyska, Elżbieta; Pociecha, Krzysztof; Krupa, Anna; Jachowicz, Renata

    2015-10-01

    A sensitive HPLC method was developed and validated for the determination of sildenafil concentrations in rat plasma (200 μL) using a liquid-liquid extraction procedure and paroxetine as an internal standard. In order to eliminate interferences and improve the peak shape, a back-extraction into an acidic solution was utilized. Chromatographic separation was achieved on a cyanopropyl bonded-phase column with a mobile phase composed of 50 m m potassium dihydrogen phosphate buffer (pH 4.5) and acetonitrile (75:25, v/v), pumped at the flow rate of 1 mL/min. A UV detector was set at 230 nm. A calibration curve was constructed within a concentration range from 10 to 1500 ng/mL. The limit of detection was 5 ng/mL. The inter- and intra-day precisions of the assay were in the ranges 2.91-7.33 and 2.61-6.18%, respectively, and the accuracies for inter- and intra-day runs were within 0.14-3.92 and 0.44-2.96%, respectively. The recovery of sildenafil was 85.22 ± 4.54%. Tests confirmed the stability of sildenafil in plasma during three freeze-thaw cycles and during long-term storage at -20 and -80°C for up to 2 months. The proposed method was successfully applied to a pharmacokinetic study in rats.

  3. Fast and precise method for Pb isotope ratio determination in complex matrices using GC-MC-ICPMS: application to crude oil, kerogen, and asphaltene samples.

    PubMed

    Sanabria-Ortega, Georgia; Pécheyran, Christophe; Bérail, Sylvain; Donard, Olivier F X

    2012-09-18

    A new method to determine Pb isotope ratio without ion-exchange-matrix separation is proposed. After acid digestion, Pb was ethylated to Et(4)Pb, separated from the digested solution (black shale, asphaltene, crude oil and kerogen) by extraction in isooctane, and then injected into a gas chromatograph coupled to a multicollector inductively coupled plasma mass spectrometer. Seven isotopes ((202)Hg, (203)Tl, (204)Pb, (205)Tl, (206)Pb, (207)Pb, (208)Pb) were monitored simultaneously with peak duration of 23 s. GC elution was operated under wet plasma conditions where a thallium standard solution was introduced to the mass spectrometer for mass bias correction. The total time of the procedure (sample preparation and analysis, after acid digestion) was reduced by a factor of 15 compared to conventional-continuous sample introduction. Data treatment was carried out using the linear regression slope method. Mass bias was corrected using the double correction method (first thallium normalization followed by classical bracketing). For the (208/206)Pb and (207/206)Pb ratios, precision (2RSD(EXT), n = 21) was 49 and 69 ppm, and the bias between experimental results and reference values was better than 0.0033 and 0.0007 ‰, when injecting 1.2 ng of ethylated Pb SRM NIST 981 solution. Results obtained by this method were validated by comparison with those obtained via conventional-continuous sample introduction. The applicability of this approach was demonstrated with the analysis of black shale, asphaltene, crude oil and kerogen samples.

  4. A rapid and precise method for the determination of vitamin D3 in rat skin by high-performance liquid chromatography.

    PubMed

    Takada, K; Okano, T; Tamura, Y; Matsui, S; Kobayashi, T

    1979-01-01

    In order to develop the investigations into photobiogenesis of vitamin D3, a rapid and precise method for the determination of the vitamin in rat skin was established by using high-performance liquid chromatography (HPLC). The proposed method included saponification of small pieces of rat skin, extraction of the unsaponifiable matter and application to HPLC using "Zorbax SIL" (straight-phase) as an adsorbent and 0.5% isopropanol in n-hexane as a mobile phase. The applicable lower limit of the method was 2ng of vitamin D3/cm2 of subcutaneous tissue-removed skin and it was possible to assay a concentration higher than 2 ng/cm2. The proposed method was applied to determine the content of vitamin D3 in rat skin obtained from in vivo and in vitro irradiation experiments. In the in vitro experiment, the yield of vitamin D3 increased in proportion to the irradiation time. On the other hand, the yield in the in vivo experiment showed a proportional increase similar to the in vitro experiment until 60 min irradiation, while a nearly constant value was obtained by irradiation for longer than 60 min. When the rat skin obtained from the in vitro experiment was irradiated with monochromatic UV rays in the range s60-350 nm, the most effective wavelength for the formation of vitamin D3 was confirmed to be 303 nm, which differs from the result obtained from the experiment in a test tube (295 nm). Moreover, the yield of vitamin D3 by irradiation with UV rays below 288 nm was extremely low, which again differed from the results of a test tube experiment. These differences were thought to be due to the filter effect of the malpighian layer in the epidermis of rat skin.

  5. Human milk oligosaccharides: evolution, structures and bioselectivity as substrates for intestinal bacteria.

    PubMed

    German, J Bruce; Freeman, Samara L; Lebrilla, Carlito B; Mills, David A

    2008-01-01

    Human milk contains a high concentration of diverse soluble oligosaccharides, carbohydrate polymers formed from a small number of monosaccharides. Novel methods combining liquid chromatography with high resolution mass spectrometry have identified approximately 200 unique oligosaccharides structures varying from 3 to 22 sugars. The increasing complexity of oligosaccharides follows the general pattern of mammalian evolution though the concentration and diversity of these structures in homo sapiens are strikingly. There is also diversity among human mothers in oligosaccharides. Milks from randomly selected mothers contain as few as 23 and as many as 130 different oligosaccharides. The functional implications of this diversity are not known. Despite the role of milk to serve as a sole nutrient source for mammalian infants, the oligosaccharides in milk are not digestible by human infants. This apparent paradox raises questions about the functions of these oligosaccharides and how their diverse molecular structures affect their functions. The nutritional function most attributed to milk oligosaccharides is to serve as prebiotics - a form of indigestible carbohydrate that is selectively fermented by desirable gut microflora. This function was tested by purifying human milk oligosaccharides and providing these as the sole carbon source to various intestinal bacteria. Indeed, the selectively of providing the complex mixture of oligosaccharides pooled from human milk samples is remarkable. Among a variety of Bifidobacteria tested only Bifidobacteria longum biovar infantis was able to grow extensively on human milk oligosaccharides as sole carbon source. The genomic sequence of this strain revealed approximately 700 genes that are unique to infantis, including a variety of co-regulated glycosidases, relative to other Bifidobacteria, implying a co-evolution of human milk oligosaccharides and the genetic capability of select intestinal bacteria to utilize them. The goal of

  6. Fermentation properties and potential prebiotic activity of Bimuno® galacto-oligosaccharide (65 % galacto-oligosaccharide content) on in vitro gut microbiota parameters.

    PubMed

    Grimaldi, Roberta; Swann, Jonathan R; Vulevic, Jelena; Gibson, Glenn R; Costabile, Adele

    2016-08-01

    Prebiotic oligosaccharides have the ability to generate important changes in the gut microbiota composition that may confer health benefits to the host. Reducing the impurities in prebiotic mixtures could expand their applications in food industries and improve their selectivity and prebiotic effect on the potential beneficial bacteria such as bifidobacteria and lactobacilli. This study aimed to determine the in vitro potential fermentation properties of a 65 % galacto-oligosaccharide (GOS) content Bimuno® GOS (B-GOS) on gut microbiota composition and their metabolites. Fermentation of 65 % B-GOS was compared with 52 % B-GOS in pH- and volume-controlled dose-response anaerobic batch culture experiments. In total, three different doses (1, 0·5 and 0·33 g equivalent to 0·1, 0·05 and 0·033 g/l) were tested. Changes in the gut microbiota during a time course were identified by fluorescence in situ hybridisation, whereas small molecular weight metabolomics profiles and SCFA were determined by 1H-NMR analysis and GC, respectively. The 65 % B-GOS showed positive modulation of the microbiota composition during the first 8 h of fermentation with all doses. Administration of the specific doses of B-GOS induced a significant increase in acetate as the major SCFA synthesised compared with propionate and butyrate concentrations, but there were no significant differences between substrates. The 65 % B-GOS in syrup format seems to have, in all the analysis, an efficient prebiotic effect. However, the applicability of such changes remains to be shown in an in vivo trial.

  7. Structural differences of prebiotic oligosaccharides influence their capability to enhance iron absorption in deficient rats.

    PubMed

    Laparra, José Moisés; Díez-Municio, Marina; Herrero, Miguel; Moreno, F Javier

    2014-10-01

    This study evaluates the influence of novel galacto-oligosaccharides derived from lactulose (GOS-Lu), kojibiose or 4'-galactosyl-kojibiose in hematological parameters of Fe homeostasis using Fe-deficient animals. Liver TfR-2, IL-6, NFκB and PPAR-γ expression (mRNA) were also determined by RT-qPCR analyses, and active hepcidin peptide production and short chain fatty acids by LC coupled to MS/MS or UV detection. Feeding animals with GOS-Lu or kojibiose together with FeCl3 increased hemoglobin (Hb) production (by 17%) and mean Hb concentration into erythrocytes relative to animals administered with FeCl3 alone (14.1% and 19.7%, respectively). Animals administered with prebiotics showed decreased plasmatic hepcidin levels, contributing to a higher intestinal absorption of the micronutrient. These data indicate that concurrent administration of these potentially prebiotic oligosaccharides together with a supplement of Fe ameliorates inflammation-mediated perturbations in the liver, according to the particular structure of the prebiotic compound, and result an attractive strategy to improve Fe absorption.

  8. Structure of the core oligosaccharide in the serotype O8 lipopolysaccharide from Klebsiella pneumoniae.

    PubMed Central

    Severn, W B; Kelly, R F; Richards, J C; Whitfield, C

    1996-01-01

    Two classes of mutants with O-antigen-deficient lipopolysaccharides were isolated from the serotype O8 reference strain, belonging to Klebsiella pneumoniae subspecies ozaenae. These mutants were selected by resistance to bacteriophage KO1-2, which recognizes and lyses strains with lipopolysaccharide molecules containing the D-galactan II O antigen. Strain RFK-11 contains a defect in O-antigen synthesis and has a complete core, including the attachment site for O antigen. This mutation is complemented by a plasmid carrying the rfb (O-antigen biosynthesis) gene cluster from the related K. pneumoniae serotype O1. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the lipopolysaccharide from strain RFK-9 has a mobility typical of deep-rough lipopolysaccharide. RFK-9 lipopolysaccharide lacks the attachment site for O antigen. Lipopolysaccharides from strains RFK-9 and RFK-11 were isolated, and their structures were determined by methylation analyses, muclear magnetic resonance spectroscopy, and mass spectroscopy. The deduced O8 core oligosaccharide includes the partial core structure reported for the K. pneumoniae subspecies pneumoniae serotype O1 lipopolysaccharide (M. Süsskind, S. Müller-Leonnies, W. Nimmich, H. Brade, and O. Holst, Carbohydr. Res. 269:C1-7, 1995), consistent with the possibility of a conserved core structure within the species. The core oligosaccharide differs from those of the genera Salmonella and Escherichia by the absence of a hexose-containing outer core, the lack of phosphate residues in the inner core, and the presence of galacturonic acid residues. PMID:8626303

  9. Legume receptors perceive the rhizobial lipochitin oligosaccharide signal molecules by direct binding

    PubMed Central

    Broghammer, Angelique; Krusell, Lene; Blaise, Mickaël; Sauer, Jørgen; Sullivan, John T.; Maolanon, Nicolai; Vinther, Maria; Lorentzen, Andrea; Madsen, Esben B.; Jensen, Knud J.; Roepstorff, Peter; Thirup, Søren; Ronson, Clive W.; Thygesen, Mikkel B.; Stougaard, Jens

    2012-01-01

    Lipochitin oligosaccharides called Nod factors function as primary rhizobial signal molecules triggering legumes to develop new plant organs: root nodules that host the bacteria as nitrogen-fixing bacteroids. Here, we show that the Lotus japonicus Nod factor receptor 5 (NFR5) and Nod factor receptor 1 (NFR1) bind Nod factor directly at high-affinity binding sites. Both receptor proteins were posttranslationally processed when expressed as fusion proteins and extracted from purified membrane fractions of Nicotiana benthamiana or Arabidopsis thaliana. The N-terminal signal peptides were cleaved, and NFR1 protein retained its in vitro kinase activity. Processing of NFR5 protein was characterized by determining the N-glycosylation patterns of the ectodomain. Two different glycan structures with identical composition, Man3XylFucGlcNAc4, were identified by mass spectrometry and located at amino acid positions N68 and N198. Receptor–ligand interaction was measured by using ligands that were labeled or immobilized by application of chemoselective chemistry at the anomeric center. High-affinity ligand binding was demonstrated with both solid-phase and free solution techniques. The Kd values obtained for Nod factor binding were in the nanomolar range and comparable to the concentration range sufficient for biological activity. Structure-dependent ligand specificity was shown by using chitin oligosaccharides. Taken together, our results suggest that ligand recognition through direct ligand binding is a key step in the receptor-mediated activation mechanism leading to root nodule development in legumes. PMID:22859506

  10. Prenatal caprine milk oligosaccharide consumption affects the development of mice offspring

    PubMed Central

    McNabb, Warren C.; Young, Wayne; Cookson, Adrian L.; Roy, Nicole C.

    2016-01-01

    1 Scope The composition of the gastrointestinal (GIT) microbiota, particularly in early life, influences the development of metabolic diseases later in life. The maternal microbiota is the main source of bacteria colonising the infant GIT and can be modified by dietary prebiotics. Our objective was to determine the effects of prenatal consumption of prebiotic caprine milk oligosaccharides (CMO) on the large intestine of female mice, milk composition, and offspring's development. 2 Methods and results C57BL/6 mice were fed either a control diet, CMO diet, or galacto‐oligosaccharide diet from mating to weaning. From weaning, some pups nursed by CMO, GOS, and control‐dams were fed the control diet for 30 days. CMO or GOS‐fed dams had increased colon length and milk protein concentration compared to control‐fed dams. At weaning, pups from CMO‐fed dams had increased body weight and colon length and increased proportions of colonic Bifidobacterium spp compared to the pups from control‐fed dams. Thirty days after weaning, pups from CMO‐fed dams had increased visceral fat weight compared to pups from control‐fed dams. 3 Conclusion Consumption of CMO by the dams during gestation and lactation improved the development of the pups, and the relative abundance of bifidobacteria and butyric acid in the colon, at weaning. PMID:27067267

  11. Enzyme catalysed production of sialylated human milk oligosaccharides and galactooligosaccharides by Trypanosoma cruzi trans-sialidase.

    PubMed

    Holck, Jesper; Larsen, Dorte M; Michalak, Malwina; Li, Haiying; Kjærulff, Louise; Kirpekar, Finn; Gotfredsen, Charlotte H; Forssten, Sofia; Ouwehand, Arthur C; Mikkelsen, Jørn D; Meyer, Anne S

    2014-03-25

    A Trypanosoma cruzi trans-sialidase (E.C. 3.2.1.18) was cloned into Pichia pastoris and expressed. The pH and temperature optimum of the enzyme was determined as pH 5.7 and 30°C. Using casein glycomacropeptide (CGMP) and lactose as sialyl-donor and acceptor respectively, the optimal donor/acceptor ratio for the trans-sialidase catalysed 3'-sialyllactose production was found to be 1:4. Quantitative amounts of 3'-sialyllactose were produced from CGMP and lactose at a yield of 40mg/g CGMP. The 3'-sialyllactose obtained exerted a stimulatory effect on selected probiotic strains, including different Bifidobacterium strains in single culture fermentations. The trans-sialidase also catalysed the transfer of sialic acid from CGMP to galacto-oligosaccharides (GOS) and to the human milk oligosaccharide (HMO) backbone lacto-N-tetraose (LNT) to produce 3'-sialyl-GOS, including doubly sialylated GOS products, and 3'-sialyl-LNT, respectively. This work thus provides proof of the concept of producing 3'-sialyllactose and potentially other sialylated HMOs as well as sialylated GOS enzymatically by trans-sialidase activity, while at the same time providing valorisation of CGMP, a co-processing product from cheese manufacture.

  12. Inulin-Type Oligosaccharides Extracted from Yacon Produce Antidepressant-Like Effects in Behavioral Models of Depression.

    PubMed

    An, Lei; Yang, Ji-Chu; Yin, Hang; Xue, Rui; Wang, Qiong; Sun, Yu Chen; Zhang, You-Zhi; Yang, Ming

    2016-12-01

    Yacon (Smallanthus sonchifolius), a traditional food in the Andean diet, is attracting global attention for its medicinal properties, which are mainly because of its high content of non-digestible oligosaccharides. The purpose of this study is to evaluate the antidepressant-like effects of inulin-type oligosaccharides extracted from yacon (YOs) in behavioral models of depression. Behavioral despair models in mice including the tail suspension test (TST) and the forced swimming test (FST) were used to determine the effects of acute YOs administration. The locomotor activity was also explored to eliminate any false-positive activity. In addition, to further investigate the antidepressant-like effects of subchronic YOs administration, the learned helplessness (LH) paradigm in rats was performed. The results demonstrated that YOs (25, 50, or 100 mg/kg, p.o.) treatment significantly reduced the immobility time in the mouse TST and FST in a U-shaped, dose-dependent manner, and showed no stimulatory effect on the locomotor activity. Furthermore, subchronic YOs (25, 50, or 100 mg/kg, p.o.) treatment significantly reversed the escape deficits in LH rats, including an increased number of escape failures and prolonged escape latency. These findings suggest that the inulin-type oligosaccharides extracted from yacon may be a prospective natural source for antidepressants. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Immunological evaluation of a synthetic Clostridium difficile oligosaccharide conjugate vaccine candidate and identification of a minimal epitope.

    PubMed

    Martin, Christopher E; Broecker, Felix; Oberli, Matthias A; Komor, Julia; Mattner, Jochen; Anish, Chakkumkal; Seeberger, Peter H

    2013-07-03

    Clostridium difficile is the cause of emerging nosocomial infections that result in abundant morbidity and mortality worldwide. Thus, the development of a vaccine to kill the bacteria to prevent this disease is highly desirable. Several recently identified bacterial surface glycans, such as PS-I and PS-II, are promising vaccine candidates to preclude C. difficile infection. To circumvent difficulties with the generation of natural PS-I due to its low expression levels in bacterial cultures, improved chemical synthesis protocols for the pentasaccharide repeating unit of PS-I and oligosaccharide substructures were utilized to produce large quantities of well-defined PS-I related glycans. The analysis of stool and serum samples obtained from C. difficile patients using glycan microarrays of synthetic oligosaccharide epitopes revealed humoral immune responses to the PS-I related glycan epitopes. Two different vaccine candidates were evaluated in the mouse model. A synthetic PS-I repeating unit CRM197 conjugate was immunogenic in mice and induced immunoglobulin class switching as well as affinity maturation. Microarray screening employing PS-I repeating unit substructures revealed the disaccharide Rha-(1→3)-Glc as a minimal epitope. A CRM197-Rha-(1→3)-Glc disaccharide conjugate was able to elicit antibodies recognizing the C. difficile PS-I pentasaccharide. We herein demonstrate that glycan microarrays exposing defined oligosaccharide epitopes help to determine the minimal immunogenic epitopes of complex oligosaccharide antigens. The synthetic PS-I pentasaccharide repeating unit as well as the Rha-(1→3)-Glc disaccharide are promising novel vaccine candidates against C. difficile that are currently in preclinical evaluation.

  14. Inulin, a flexible oligosaccharide. II: Review of its pharmaceutical applications.

    PubMed

    Mensink, Maarten A; Frijlink, Henderik W; van der Voort Maarschalk, Kees; Hinrichs, Wouter L J

    2015-12-10

    Inulin is a flexible oligosaccharide which has been used primarily in food for decades. Recently new applications in the pharmaceutical arena were described. In a previous review (Mensink et al. (2015). Carbohydrate Polymers, 130, 405) we described the physicochemical characteristics of inulin, characteristics which make inulin a highly versatile substance. Here, we review its pharmaceutical applications. Applications of inulin that are addressed are stabilization of proteins, modified drug delivery (dissolution rate enhancement and drug targeting), and lastly physiological and disease-modifying effects of inulin. Further uses of inulin include colon specific drug administration and stabilizing and adjuvating vaccine formulations. Overall, the uses of inulin in the pharmaceutical area are very diverse and research is still continuing, particularly with chemically modified inulins. It is therefore likely that even more applications will be found for this flexible oligosaccharide.

  15. Capillary electrophoresis of neutral carbohydrates: mono-, oligosaccharides, glycosides.

    PubMed

    Campa, Cristiana; Rossi, Marco

    2008-01-01

    This chapter reports an overview of the recent advances in the analysis of neutral sugars by capillary electrophoresis (CE); furthermore, some relevant reviews and research articles in the field are tabulated. Comparison of CE with chromatography is also presented, with special attention to separation efficiency and sensitivity. The main routes aimed at pretreatment and CE analysis of uncharged mono-, oligosaccharides, and glycosides are described. Representative examples of such procedures are reported in detail, upon describing robust methodologies for the study of (1) neutral mono- and oligosaccharides derivatized by reductive amination and by formation of glycosylamines; (2) underivatized mono- and di-saccharides analyzed using highly alkaline buffers; and (3) anomeric couples of glycosides separated using borate-based buffers.

  16. Apparatus Makes Precisely Saturated Solutions

    NASA Technical Reports Server (NTRS)

    Pusey, Marc L.

    1989-01-01

    Simple laboratory apparatus establishes equilibrium conditions of temperature and concentration in solutions for use in precise measurements of saturation conditions. With equipment typical measurement of saturation concentration of protein in solution established and measured within about 24 hours. Precisely saturated solution made by passing solvent or solution slowly along column packed with solute at precisely controlled temperature. If necessary, flow stopped for experimentally determined interval to allow equilibrium to be established in column.

  17. Characterization of protein-linked oligosaccharides in trypanosomatid flagellates.

    PubMed

    Mendelzon, D H; Previato, J O; Parodi, A J

    1986-03-01

    Protein-linked, endo-beta-N-acetylglucosaminidase H-sensitive oligosaccharides were isolated from several trypanosomatids incubated with [U-14C]glucose. Structural analysis of the compounds revealed that Man9GlcNAc2 was the oligosaccharide transferred from dolichol-P-P derivatives to proteins in Trypanosoma dionisii, Trypanosoma conorhini, Leptomonas samueli and Herpetomonas samuelpessoai and Man6GlcNAc2 in Blastocrithidia culicis and Leishmania adleri. In all cases, transiently glucosylated compounds were detected: Glc1Man7-9GlcNAc2 in T. dionisii, T. conorhini, L. samueli; Glc1Man9GlcNAc2 in H. samuelpessoai, Glc1Man6GlcNAc2 in B. culicis and Glc1Man6GlcNAc2 and Glc1Man5GlcNAc2 in L. adleri. The mechanism of protein glycosylation in T. dionisii and T. conorhini appeared to be similar to that described before for Trypanosoma cruzi epimastigotes, although some differences were found between the structures of the main isomers of Man7GlcNAc2 and Man8GlcNAc2 present in T. conorhini and T. cruzi. Differences between the mechanisms of glycosylation occurring in Leishmania mexicana and L. adleri were also found: Man6GlcNAc2 in the latter microorganism was demannosylated to Man5GlcNAc2, a step not detected in the former parasite. A novel substituent in N-linked high mannose-type oligosaccharides was found in L. samueli and H. samuelpessoai: galactose in the furanose configuration. In the latter trypanosomatid, Man9GlcNAc2 was demannosylated only to Man8GlcNAc2, whereas in all other parasites in which the same oligosaccharide was transferred to proteins, Man5-7GlcNAc2 were also detected.

  18. Gaseous response to ingestion of a poorly absorbed fructo-oligosaccharide sweetener.

    PubMed

    Stone-Dorshow, T; Levitt, M D

    1987-07-01

    Fructo-oligosaccharides are naturally occurring sweet substances that are poorly absorbed and have the potential to be clinically useful nonnutritive sweeteners. Because most nonabsorbed carbohydrates are fermented yielding gas, we assessed flatulent symptoms and H2 excretion during ingestion of fructo-oligosaccharide (5 g tid) for 12 d. Ten subjects had significantly greater flatulence while taking the oligosaccharide than did five subjects taking sucrose (5 g tid). Breath H2 after 10 g fructo-oligosaccharide was similar to that of 10 g lactulose, suggesting near total malabsorption of the fructo-oligosaccharide. Although previous studies found a marked diminution in breath H2 after prolonged exposure to lactulose, breath H2 response increased by 50% after a 12-d period on the oligosaccharide and gaseous symptoms did not improve. We conclude that adaptation of colonic bacteria to carbohydrate malabsorption is variable and may depend upon quantity or nature of the carbohydrate.

  19. In vitro fermentability of sugar beet pulp derived oligosaccharides using human and pig fecal inocula.

    PubMed

    Leijdekkers, Antonius G M; Aguirre, Marisol; Venema, Koen; Bosch, Guido; Gruppen, Harry; Schols, Henk A

    2014-02-05

    The in vitro fermentation characteristics of different classes of sugar beet pectic oligosaccharides (SBPOS) were studied using human and pig fecal inocula. The SBPOS consisted mainly of partially acetylated rhamnogalacturonan oligosaccharides and partially methyl-esterified/acetylated homogalacturonan oligosaccharides. Some SBPOS contained an unsaturated galacturonic acid residue at their non-reducing end. It was shown that SBPOS could be completely fermented by human and pig fecal microbiota, thereby producing butyrate yet mainly acetate and propionate as metabolites. The degradation of SBPOS by pig fecal microbiota was different and much slower compared to human fecal microbiota. In general, rhamnogalacturonan oligosaccharides were degraded slower than homogalacturonan oligosaccharides. Acetylation of rhamnogalacturonan oligosaccharides lowered the degradation rate by pig fecal microbiota but not by human fecal microbiota. No classic bifidogenic effect was shown for SBPOS using human fecal inoculum. However, several other potentially interesting modifications in the microbiota composition that can be associated with host health were observed, which are discussed.

  20. The chromatographic analysis of oligosaccharides and preparation of 1-kestose and nystose in yacon.

    PubMed

    Zhu, Zhen-Yuan; Lian, Hong-Yu; Si, Chuan-Ling; Liu, Yang; Liu, Nian; Chen, Jing; Ding, Li-Na; Yao, Qiang; Zhang, Yongmin

    2012-05-01

    The thin-layer chromatographic analysis of the crude oligosaccharides extracted from yacon revealed the presence of glucose, fructose, sucrose, 1-kestose and nystose. The qualitative and quantitative analysis was carried out on oligosaccharides by high pressure liquid chromatography and the results showed that the contents of d-glucose, fructose, sucrose, 1-kestose, nystose and 1-fructofuranosyl nystose in oligosaccharides were 38.30%, 16.44%, 14.58%, 12.29%, 12.17%, 6.20%, respectively. The content of the fructooligosaccharides in oligosaccharides was 30.66%. The crude oligosaccharides were separated and purified by silica gel column chromatography. The two fractions obtained from crude oligosaccharides were 1-kestose and nystose, which were identified by mass spectra. The yield of 1-kestose and nystose were 10.36% and 9.73%, respectively. The purity of 1-kestose was 82.9% and of nystose was 73.6%.

  1. Proteomics analysis of Bacillus licheniformis in response to oligosaccharides elicitors.

    PubMed

    Reffatti, Patricia Fernanda; Roy, Ipsita; Odell, Mark; Keshavarz, Tajalli

    2014-01-01

    The role of oligosaccharides as biotic elicitors has been recognised in the enhanced production of antibiotics from fungal and bacterial cultures. The yield of bacitracin A in cultures of Bacillus licheniformis was increased after supplementation with oligoguluronate (OG), and mannan oligosaccharides (MO) and its mechanism at transcription level been established already. However, the elicitation mechanism at post transcriptional level has not been reported so far. In this paper we investigate changes in proteomics of B. licheniformis in presence of the oligosaccharide elicitors OG and MO. Differentially expressed proteins were examined using 2D-PAGE stained with colloidal Coomassie and were further identified by LC-MS/MS. We identified 19 differentially expressed proteins including those involved in carbon metabolism, energy generation, amino acid biosynthesis, oxidative and general stress response. The novel findings of this work, together with previous reports, contribute to the unravelling of the overall mechanism of elicitation in B. licheniformis cultures and reliability of the use of these elicitors for potential industrial application.

  2. Synthesis of heparin-like oligosaccharides on polymer supports.

    PubMed

    Ojeda, Rafael; Terentí, Olimpia; de Paz, José-Luis; Martín-Lomas, Manuel

    2004-01-01

    The biological functions of a variety of proteins are regulated by heparan sulfate glycosaminoglycans. In order to facilitate the elucidation of the molecular basis of glycosaminoglycan-protein interactions we have developed syntheses of heparin-like oligosaccharides on polymer supports. A completely stereoselective strategy previously developed by us for the synthesis of these oligosaccharides in solution has been extended to the solid phase using an acceptor-bound approach. Both a soluble polymer support and a polyethylene glycol-grafted polystyrene resin have been used and different strategies for the attachment of the acceptor to the support have been explored. The attachment of fully protected disaccharide building blocks to a soluble support through the carboxylic group of the uronic acid unit by a succinic ester linkage, the use of trichloroacetimidates as glycosylating agents and of a functionalized Merryfield type resin for the capping process allowed for the construction of hexasaccharide and octasaccharide fragments containing the structural motif of the regular region of heparin. This strategy may facilitate the synthesis of glycosaminoglycan oligosaccharides by using the required building blocks in the glycosylation sequence.

  3. Engineering chemical reactivity on cell surfaces through oligosaccharide biosynthesis

    SciTech Connect

    Mahal, L.K.; Yareme, K.J.; Bertozzi, C.R.

    1997-05-16

    Cell surface oligosaccharide can be engineered to display unusual functional groups for the selective chemical remodeling of cell surfaces. An unnatural derivative of N-acetyl-mannosamine, which has a ketone group, was converted to the corresponding sialic acid and incorporated into cell surface oligosaccharide metabolically, resulting in the cell surface display of ketone groups. The ketone group on the cell surface can then be covalently ligated under physiological conditions with molecules carrying a complementary reactive functional group such as the hydrazide. Cell surface reactions of this kind should prove useful in the introduction of new recognition epitopes, such as peptides, oligosaccharide, or small organic molecules, onto cell surfaces and in the subsequent modulation of cell-cell or cell-small molecule binding events. The versatility of this technology was demonstrated by an example of selective drug delivery. Cells were decorated with biotin through selective conjugation to ketone groups, and selectively killed in the presence of a ricin A chain-avidin conjugate. 30 refs., 4 figs.

  4. More Questions on Precision Teaching.

    ERIC Educational Resources Information Center

    Raybould, E. C.; Solity, J. E.

    1988-01-01

    Precision teaching can accelerate basic skills progress of special needs children. Issues discussed include using probes as performance tests, charting daily progress, using the charted data to modify teaching methods, determining appropriate age levels, assessing the number of students to be precision taught, and carefully allocating time. (JDD)

  5. Structural study of asparagine-linked oligosaccharide moiety of taste-modifying protein, miraculin.

    PubMed

    Takahashi, N; Hitotsuya, H; Hanzawa, H; Arata, Y; Kurihara, Y

    1990-05-15

    The structures of the N-linked oligosaccharides of miraculin, which is a taste modifying glycoprotein isolated from miracle fruits, berries of Richadella dulcifica, are reported. Asparagine-linked oligosaccharides were released from the protein by glycopeptidase (almond) digestion. The reducing ends of the oligosaccharide chains thus obtained were aminated with a fluorescent reagent, 2-aminopyridine, and the mixture of pyridylamino derivatives of the oligosaccharides was separated by high performance liquid chromatography (HPLC) on an ODS-silica column. More than five kinds of oligosaccharide fractions were separated by the one chromatographic run. The structure of each oligosaccharide thus isolated was analyzed by a combination of sequential exoglycosidase digestion and another kind of HPLC with an amidesilica column. Furthermore, high resolution proton nuclear magnetic resonance (1H NMR) measurements were carried out. It was found that 1) five oligosaccharides obtained are a series of compounds with xylose-containing common structural core, Xyl beta 1----2 (Man alpha 1----6) Man beta 1----4-GlcNAc beta 1----4 (Fuca1----3)GlcNAc, 2) a variety of oligosaccharide structures are significant for two glycosylation sites, Asn-42 and Asn-186, and 3) two new oligosaccharides, B and D, with unusual structures containing monoantennary complex-type were characterized. (formula; see text)

  6. Studies on the asparagine-linked oligosaccharides from cartilage-specific proteoglycan

    SciTech Connect

    Cioffi, L.C.

    1987-01-01

    Chondrocytes synthesize and secrete a cartilage-specific proteoglycan (PG-H) as one of their major products. This proteoglycan has attached to it several types of carbohydrate chains, including chondroitin sulfate, keratan sulfate, O-linked oligosaccharides, and asparagine-linked oligosaccharides. The asparagine-linked oligosaccharides found on PG-H were investigated in these studies. Methodology was developed for the isolation and separation of standard of standard complex and high mannose type oligosaccharides. This included digesting glycoproteins with N-glycanase and separation of the oligosaccharides according to type by concanavalin-A lectin chromatography. The different oligosaccharide types were then analyzed by high pressure liquid chromatography. This methodology was used in the subsequent studies on the PG-H asparagine-linked oligosaccharides. Initially, the asparagine-linked oligosaccharides recovered from the culture medium (CM) and cell-associated (Ma) fractions of PG-H from of tibial chondrocytes were labeled with (/sup 3/H)-mannose and the oligosaccharides were isolated and analyzed.

  7. A new sialyloligosaccharide from human milk: isolation and characterization using anti-oligosaccharide antibodies

    SciTech Connect

    Prieto, P.A.; Smith, D.F.

    1984-03-01

    A previously undescribed sialyloligosaccharide has been isolated from human milk using a specific anti-sialyloligosaccharide antibody. Structural studies of the radiolabeled oligosaccharide by enzyme degradation and binding by specific anti-oligosaccharide sera are consistent with the following structure: (sequence in text) The oligosaccharide is present only in milk from donors who secrete A, B, or H blood group substances; this is consistent with the requirement of at least one copy of the Se (Secretor) gene necessary for the synthesis of oligosaccharides with Fuc alpha 1-2Gal . . . linkages.

  8. 1H NMR characterization of a hen ovalbumin tyrosinamide N-linked oligosaccharide library.

    PubMed

    Corradi Da Silva, M L; Stubbs, H J; Tamura, T; Rice, K G

    1995-04-20

    A library of 15 N-linked oligosaccharide structures was prepared from ovalbumin and characterized using high-field NMR and mass spectrometry. The oligosaccharides were enzymatically released from ovalbumin glycopeptides, and the reducing ends were reacted with ammonium bicarbonate to form oligosaccharide-glycosylamines. These reacted with Boc-tyrosine-N-hydroxysuccinimide ester, resulting in a mixture of tyrosinamide-oligosaccharides. The Boc group was removed to expose an amine terminus which enhanced the resolution of tyrosinamide-oligosaccharides when chromatographed on reverse-phase HPLC. Ten major and five minor oligosaccharides were purified on a micromole scale and characterized using 1H NMR and FAB-MS. The structures include high-mannose, hybrid, and complex oligosaccharides possessing from two to five antenna, providing the most complete definition of ovalbumin N-linked oligosaccharides to date. The resulting library is well suited to biological studies due to the presence of a single terminal tyrosine residue on each oligosaccharide that allows radioiodination or the attachment of additional probes to these glycoconjugates prior to biological studies.

  9. An Update on Oligosaccharides and Their Esters from Traditional Chinese Medicines: Chemical Structures and Biological Activities

    PubMed Central

    Chen, Xiang-Yang; Wang, Ru-Feng; Liu, Bin

    2015-01-01

    A great number of naturally occurring oligosaccharides and oligosaccharide esters have been isolated from traditional Chinese medicinal plants, which are used widely in Asia and show prominent curative effects in the prevention and treatment of kinds of diseases. Numerous in vitro and in vivo experiments have revealed that oligosaccharides and their esters exhibited various activities, including antioxidant, antidepressant, cytotoxic, antineoplastic, anti-inflammatory, neuroprotective, cerebral protective, antidiabetic, plant growth-regulatory, and immunopotentiating activities. This review summarizes the investigations on the distribution, chemical structures, and bioactivities of natural oligosaccharides and their esters from traditional Chinese medicines between 2003 and 2013. PMID:25861364

  10. Synthesis, separation, and characterization of amphiphilic sulfated oligosaccharides enabled by reversed-phase ion pairing LC and LC-MS methods.

    PubMed

    Fenner, Amanda M; Kerns, Robert J

    2011-12-13

    Synthesis of amphiphilic oligosaccharides is problematic because traditional methods for separating and purifying oligosaccharides, including sulfated oligosaccharides, are generally not applicable to working with amphiphilic sugars. We report here RPIP-LC and LC-MS methods that enable the synthesis, separation, and characterization of amphiphilic N-arylacyl O-sulfonated aminoglycosides, which are being pursued as small-molecule glycosaminoglycan mimics. The methods described in this work for separating and characterizing these amphiphilic saccharides are further applied to a number of uses: monitoring the progression of sulfonation reactions with analytical RP-HPLC, characterizing sulfate content for individual molecules with ESI-MS, determining the degree of sulfation for products having mixed degrees of sulfation with HPLC and LC-MS, and purifying products with benchtop C18 column chromatography. We believe that the methods described here will be broadly applicable to enabling the synthesis, separation, and characterization of amphiphilic, sulfated, and phosphorylated oligosaccharides and other types of molecules substituted to varying degrees with both anionic and hydrophobic groups.

  11. Chemical characterization of milk oligosaccharides of the koala (Phascolarctos cinereus).

    PubMed

    Urashima, Tadasu; Taufik, Epi; Fukuda, Rino; Nakamura, Tadashi; Fukuda, Kenji; Saito, Tadao; Messer, Michael

    2013-11-01

    Previous structural characterizations of marsupial milk oligosaccharides had been performed in only two macropod species, the tammar wallaby and the red kangaroo. To clarify the homology and heterogeneity of milk oligosaccharides among marsupial species, which could provide information on their evolution, the oligosaccharides of the koala milk carbohydrate fraction were characterized in this study. Neutral and acidic oligosaccharides were separated from the carbohydrate fraction of milk of the koala, a non-macropod marsupial, and characterized by (1)H-nuclear magnetic resonance spectroscopy. The structures of the neutral saccharides were found to be Gal(β1-4)Glc (lactose), Gal(β1-3)Gal(β1-4)Glc (3'-galactosyllactose), Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc (3',3″-digalactosyllactose), Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (lacto-N-novopentaose I) and Gal(β1-3){Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-6)}Gal(β1-4)Glc (fucosyl lacto-N-novopentaose I), while those of the acidic saccharides were Neu5Ac(α2-3)Gal(β1-4)Glc (3'-SL), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-4)Gal (sialyl 3'-galactosyllactose), Neu5Ac(α2-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose a), Gal(β1-3)[Neu5Ac(α2-6)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose b), Gal(β1-3)[Neu5Ac(α2-3)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose c), and Neu5Ac(α2-3)Gal(β1-3){Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-6)}Gal(β1-4)Glc (fucosyl sialyl lacto-N-novopentaose a). The neutral oligosaccharides, other than fucosyl lacto-N-novopentaose I, a novel hexasaccharide, had been found in milk of the tammar wallaby, a macropod marsupial, while the acidic oligosaccharides, other than fucosyl sialyl lacto-N-novopentaose a had been identified in milk carbohydrate of the red kangaroo. The presence of fucosyl oligosaccharides is a significant feature of koala milk, in which it differs from milk of the tammar wallaby and the red kangaroo.

  12. Novel, Precise, Accurate Ion-Pairing Method to Determine the Related Substances of the Fondaparinux Sodium Drug Substance: Low-Molecular-Weight Heparin

    PubMed Central

    Deshpande, Amol A.; Madhavan, P.; Deshpande, Girish R.; Chandel, Ravi Kumar; Yarbagi, Kaviraj M.; Joshi, Alok R.; Moses Babu, J.; Murali Krishna, R.; Rao, I. M.

    2016-01-01

    Fondaparinux sodium is a synthetic low-molecular-weight heparin (LMWH). This medication is an anticoagulant or a blood thinner, prescribed for the treatment of pulmonary embolism and prevention and treatment of deep vein thrombosis. Its determination in the presence of related impurities was studied and validated by a novel ion-pair HPLC method. The separation of the drug and its degradation products was achieved with the polymer-based PLRPs column (250 mm × 4.6 mm; 5 μm) in gradient elution mode. The mixture of 100 mM n-hexylamine and 100 mM acetic acid in water was used as buffer solution. Mobile phase A and mobile phase B were prepared by mixing the buffer and acetonitrile in the ratio of 90:10 (v/v) and 20:80 (v/v), respectively. Mobile phases were delivered in isocratic mode (2% B for 0–5 min) followed by gradient mode (2–85% B in 5–60 min). An Evaporative Light Scattering Detector (ELSD) was connected to the LC system to detect the responses of chromatographic separation. Further, the drug was subjected to stress studies for acidic, basic, oxidative, photolytic, and thermal degradations as per ICH guidelines and the drug was found to be labile in acid, base hydrolysis, and oxidation, while stable in neutral, thermal, and photolytic degradation conditions. The method provided linear responses over the concentration range of the LOQ to 0.30% for each impurity with respect to the analyte concentration of 12.5 mg/mL, and regression analysis showed a correlation coefficient value (r2) of more than 0.99 for all the impurities. The LOD and LOQ were found to be 1.4 µg/mL and 4.1 µg/mL, respectively, for fondaparinux. The developed ion-pair method was validated as per ICH guidelines with respect to accuracy, selectivity, precision, linearity, and robustness. PMID:27110496

  13. Novel high-molecular weight fucosylated milk oligosaccharides identified in dairy streams.

    PubMed

    Mehra, Raj; Barile, Daniela; Marotta, Mariarosaria; Lebrilla, Carlito B; Chu, Caroline; German, J Bruce

    2014-01-01

    Oligosaccharides are the third largest component in human milk. This abundance is remarkable because oligosaccharides are not digestible by the newborn, and yet they have been conserved and amplified during evolution. In addition to encouraging the growth of a protective microbiota dominated by bifidobacteria, oligosaccharides have anti-infective activity, preventing pathogens from binding to intestinal cells. Although it would be advantageous adding these valuable molecules to infant milk formula, the technologies to reproduce the variety and complexity of human milk oligosaccharides by enzymatic/organic synthesis are not yet mature. Consequently, there is an enormous interest in alternative sources of these valuable oligosaccharides. Recent research has demonstrated that bovine milk and whey permeate also contain oligosaccharides. Thus, a thorough characterization of oligosaccharides in bovine dairy streams is an important step towards fully assessing their specific functionalities. In this study, bovine milk oligosaccharides (BMOs) were concentrated by membrane filtration from a readily available dairy stream called "mother liquor", and analyzed by high accuracy MALDI FT-ICR mass spectrometry. The combination of HPLC and accurate mass spectrometry allowed the identification of ideal processing conditions leading to the production of Kg amount of BMO enriched powders. Among the BMOs identified, 18 have high-molecular weight and corresponded in size to the most abundant oligosaccharides present in human milk. Notably 6 oligosaccharides contained fucose, a sugar monomer that is highly abundant in human milk, but is rarely observed in bovine milk. This work shows that dairy streams represent a potential source of complex milk oligosaccharides for commercial development of unique dairy ingredients in functional foods that reproduce the benefits of human milk.

  14. Comparison of amino acid digestibility of feedstuffs determined with the precision-fed cecectomized rooster assay and the standardized ileal amino acid digestibility assay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to evaluate and compare amino acid digestibility of several feedstuffs using 2 commonly accepted methods: the precision-fed cecectomized rooster assay (PFR) and the standardized ileal amino acid assay (SIAAD). Six corn, 6 corn distillers dried grains with or without s...

  15. Galactoglucomannan Oligosaccharide Supplementation Affects Nutrient Digestibility, Fermentation End-Product Production, and Large Bowel Microbiota of the Dog

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A galactoglucomannan oligosaccharide (GGMO) obtained from fiberboard production was evaluated as a dietary supplement for dogs. The GGMO substrate contained high concentrations of oligosaccharides containing mannose, xylose, and glucose, with the mannose component accounting for 35% of dry matter. ...

  16. GOCE Precise Science Orbits

    NASA Astrophysics Data System (ADS)

    Bock, Heike; Jäggi, Adrian; Meyer, Ulrich; Beutler, Gerhard; Heinze, Markus; Hugentobler, Urs

    GOCE (Gravity field and steady-state Ocean Circulation Explorer), as the first ESA (European Space Agency) Earth Explorer Core Mission, is dedicated for gravity field recovery of unprece-dented accuracy using data from the gradiometer, its primary science instrument. Data from the secondary instrument, the 12-channel dual-frequency GPS (Global Positioning System) receiver, is used for precise orbit determination of the satellite. These orbits are used to accu-rately geolocate the gradiometer observations and to provide complementary information for the long-wavelength part of the gravity field. A precise science orbit (PSO) product is provided by the GOCE High-Level Processing Facility (HPF) with a precision of about 2 cm and a 1-week latency. The reduced-dynamic and kinematic orbit determination strategies for the PSO product are presented together with results of about one year of data. The focus is on the improvement achieved by the use of empirically derived azimuth-and elevation-dependent variations of the phase center of the GOCE GPS antenna. The orbits are validated with satellite laser ranging (SLR) measurements.

  17. Anticonvulsant and neuroprotective effects of oligosaccharides from Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum (Higher Basidiomycetes).

    PubMed

    Tello, Isaac; Campos-Pena, Victoria; Montiel, Elizur; Rodriguez, Veronica; Aguirre-Moreno, Alma; Leon-Rivera, Ismael; Del Rio-Portilla, Federico; Herrera-Ruiz, Maribel; Villeda-Hernandez, Juana

    2013-01-01

    An oligosaccharide fraction isolated from the mycelium of the Lingzhi or Reishi medicinal mushroom Ganoderma lucidum (GLOS) was separated by size-exclusion chromatography. The chemical structure of GLOS consists of a disaccharide repeating unit [-4-β-1-Galf(1-6)-O-(β-Glcp)-1-]n (n=3,4). In addition, this study was undertaken to determine the possible anticonvulsant and neuroprotective effects of GLOS (10-80 mg/kg) on kainic acid (KA)-induced seizures. The behavioral alterations and histopathology of hippocampal neurons were studied. Our results show that GLOS inhibited convulsions in rats from KA-induced seizures, reduced the degeneration pattern in the CA3 region of rats, decreased astrocytic reactivity, and reduced the expression of IL-1β and TNF-α induced by KA. These results indicate a potential anticonvulsant and neuroprotective effects of GLOS.

  18. Fermentable oligosaccharides, disaccharides, monosaccharides and polyols: role in irritable bowel syndrome.

    PubMed

    Tuck, Caroline J; Muir, Jane G; Barrett, Jacqueline S; Gibson, Peter R

    2014-09-01

    Irritable bowel syndrome (IBS) was previously left poorly treated despite its high prevalence and cost. Over the past decade, significant research has been conducted providing new dietary strategies for IBS management. The 'low fermentable oligosaccharides, disaccharides, monosaccharides and polyols diet' has shown symptom improvement in 68-76% of patients. Randomized, controlled trials have now proven its efficacy. The diet, low in poorly absorbed and fermentable carbohydrates, uses dietary restriction and re-challenge to determine individual tolerance to various short-chain carbohydrates. However there may be potential detrimental effects of the diet in the long term, due to potential changes to the gastrointestinal microbiota. Appropriate dietary education and management of the diet is imperative. Future research should focus on the relevance of changes to the microbiota and ways to liberalize the dietary restrictions.

  19. Optimization of galacto-oligosaccharide production by Bifidobacterium infantis RW-8120 using response surface methodology.

    PubMed

    Roy, D; Daoudi, L; Azaola, A

    2002-11-01

    Oligosaccharide (OS) production, cell concentration (2 x 10(9) colony-forming unit/ml), lactose concentration (25% wt/vol), reaction time (6 h), and temperature (50 degrees C) were chosen as the central condition of the central composite design (CCD) for optimizing the production process using Bifidobacterium infantis RW-8120 in skim milk. Statistical analysis (P<0.01) revealed that the most relevant variable concerning OS production and yield was the lactose concentration. The coefficient of determination (R(2)) is good for the second-order OS production model (0.92) and fairly good for the second-order nonlinear OS yield model (0.816). An increase of lactose concentration and temperature resulted in a higher OS production. The optimal values for OS production appear to be near the area associated with the central points of the modeling design except for the lactose concentration, which was 40% (wt/vol) of the final volume.

  20. Structure-based analysis of domain function of chitin oligosaccharide deacetylase from Vibrio parahaemolyticus.

    PubMed

    Hirano, Takako; Sugiyama, Kanako; Sakaki, Yuta; Hakamata, Wataru; Park, Sam-Yong; Nishio, Toshiyuki

    2015-01-02

    The X-ray crystal structure of chitin oligosaccharide deacetylase from Vibrio parahaemolyticus (Vp-COD) was determined at an 1.35 Å resolution. The amino acid sequence and structure of Vp-COD show that the enzyme comprises one polysaccharide deacetylase domain (PDD) and two carbohydrate-binding domains (CBDs). On the basis of a chitin-binding assay with Vp-COD and its CBDs-deleted mutant, it was confirmed that CBDs can adhere to chitin. The catalytic activity of the CBDs-deleted mutant was only mildly depressed compared with that of Vp-COD, indicating that CBDs are unlikely to affect the configuration of the active center residues in active site of PDD.

  1. The Galectin CvGal1 from the Eastern Oyster (Crassostrea virginica) Binds to Blood Group A Oligosaccharides on the Hemocyte Surface*

    PubMed Central

    Feng, Chiguang; Ghosh, Anita; Amin, Mohammed N.; Giomarelli, Barbara; Shridhar, Surekha; Banerjee, Aditi; Fernández-Robledo, José A.; Bianchet, Mario A.; Wang, Lai-Xi; Wilson, Iain B. H.; Vasta, Gerardo R.

    2013-01-01

    The galectin CvGal1 from the eastern oyster (Crassostrea virginica), which possesses four tandemly arrayed carbohydrate recognition domains, was previously shown to display stronger binding to galactosamine and N-acetylgalactosamine relative to d-galactose. CvGal1 expressed by phagocytic cells is “hijacked” by the parasite Perkinsus marinus to enter the host, where it proliferates and causes systemic infection and death. In this study, a detailed glycan array analysis revealed that CvGal1 preferentially recognizes type 2 blood group A oligosaccharides. Homology modeling of the protein and its oligosaccharide ligands supported this preference over type 1 blood group A and B oligosaccharides. The CvGal ligand models were further validated by binding, inhibition, and competitive binding studies of CvGal1 and ABH-specific monoclonal antibodies with intact and deglycosylated glycoproteins, hemocyte extracts, and intact hemocytes and by surface plasmon resonance analysis. A parallel glycomic study carried out on oyster hemocytes (Kurz, S., Jin, C., Hykollari, A., Gregorich, D., Giomarelli, B., Vasta, G. R., Wilson, I. B. H., and Paschinger, K. (2013) J. Biol. Chem. 288,) determined the structures of oligosaccharides recognized by CvGal1. Proteomic analysis of the hemocyte glycoproteins identified β-integrin and dominin as CvGal1 “self”-ligands. Despite strong CvGal1 binding to P. marinus trophozoites, no binding of ABH blood group antibodies was observed. Thus, parasite glycans structurally distinct from the blood group A oligosaccharides on the hemocyte surface may function as potentially effective ligands for CvGal1. We hypothesize that carbohydrate-based mimicry resulting from the host/parasite co-evolution facilitates CvGal1-mediated cross-linking to β-integrin, located on the hemocyte surface, leading to cell activation, phagocytosis, and host infection. PMID:23824193

  2. Detection of milk oligosaccharides in plasma of infants

    PubMed Central

    Ruhaak, L. Renee; Stroble, Carol; Underwood, Mark A.; Lebrilla, Carlito B.

    2014-01-01

    Human Milk Oligosaccharides (HMO) are one of the major components of human milk. HMO are non-digestible by the human gut, where they are known to play important functions as prebiotics and decoys for binding pathogens. Moreover, it has been proposed that HMO may provide sialic acids to the infant that are important in brain development, however this would require absorption of HMO into the bloodstream. HMO have consistently been found in the urine of humans and other mammals, suggesting systemic absorption. Here we present a procedure for the profiling of milk oligosaccharides (MO) in plasma samples obtained from 13 term infants hospitalized for surgery for congenital heart disease. The method comprises protein denaturation, oligosaccharide reduction and porous graphitized carbon solid phase extraction for purification followed by analysis using nHPLC-PGC-chip-TOF-MS. Approximately 15 free MO were typically observed in the plasma of human infants, including LNT, LDFP, LNFT, 3’SL, 6’SL, 3’SLN and 6’SLN, of which the presence was confirmed using fragmentation studies. A novel third isomer of SLN, not found in human or bovine milk was also consistently detected. Differences in the free MO profiles were observed between infants that were totally formula-fed and infants that received at least some part breast milk. Our results indicate that free MO similar in structure to those found in human milk and urine are present in the blood of infants. The method and results presented here will facilitate further research toward the possible roles of free MO in the development of the infant. PMID:25059723

  3. Predicted configurations of oligosaccharide extensions in the lipooligosaccharide of nontypeable Haemophilus influenzae isolates.

    PubMed

    McCrea, Kirk W; Xie, Jingping; Daniel, Deborah; Ulrich-Lewis, Justin Theophilus; Zhang, Lixin

    2014-07-01

    Lipooligosaccharide configurations were predicted in nontypeable Haemophilus influenzae isolates based on the presence of seven oligosaccharide extension-initiating genes (or alleles). Predicted configurations with 2 to 3 oligosaccharide extensions were more prevalent among middle ear than throat strains. In addition, strains with these configurations averaged higher levels of serum resistance than strains with other configurations.

  4. Understanding the fundamental mechanism behind accumulation of oligosaccharides during high solids loading enzymatic hydrolysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During enzymatic hydrolysis of biomass, polysaccharides are cleaved by glycosyl hydrolases to soluble oligosaccharides and further hydrolyzed by ß-glucosidase, ß-xylosidase and other enzymes to monomeric sugars. However, commercial enzyme mixtures do not hydrolyze all of these oligosaccharides and v...

  5. Structural Basis for Norovirus Inhibition by Human Milk Oligosaccharides

    PubMed Central

    Weichert, Stefan; Koromyslova, Anna; Singh, Bishal K.; Hansman, Satoko; Jennewein, Stefan; Schroten, Horst

    2016-01-01

    Histo-blood group antigens (HBGAs) are important binding factors for norovirus infections. We show that two human milk oligosaccharides, 2′-fucosyllactose (2′FL) and 3-fucosyllactose (3FL), could block norovirus from binding to surrogate HBGA samples. We found that 2′FL and 3FL bound at the equivalent HBGA pockets on the norovirus capsid using X-ray crystallography. Our data revealed that 2′FL and 3FL structurally mimic HBGAs. These results suggest that 2′FL and 3FL might act as naturally occurring decoys in humans. PMID:26889023

  6. Conformational analysis of oligosaccharides and polysaccharides using molecular dynamics simulations.

    PubMed

    Frank, Martin

    2015-01-01

    Complex carbohydrates usually have a large number of rotatable bonds and consequently a large number of theoretically possible conformations can be generated (combinatorial explosion). The application of systematic search methods for conformational analysis of carbohydrates is therefore limited to disaccharides and trisaccharides in a routine analysis. An alternative approach is to use Monte-Carlo methods or (high-temperature) molecular dynamics (MD) simulations to explore the conformational space of complex carbohydrates. This chapter describes how to use MD simulation data to perform a conformational analysis (conformational maps, hydrogen bonds) of oligosaccharides and how to build realistic 3D structures of large polysaccharides using Conformational Analysis Tools (CAT).

  7. Hyaluronidase and Hyaluronan Oligosaccharides Promote Neurological Recovery after Intraventricular Hemorrhage

    PubMed Central

    Vinukonda, Govindaiah; Dohare, Preeti; Arshad, Arslan; Zia, Muhammad T.; Panda, Sanjeet; Korumilli, Ritesh; Kayton, Robert; Hascall, Vincent C.; Lauer, Mark E.

    2016-01-01

    Intraventricular hemorrhage (IVH) in premature infants results in inflammation, arrested oligodendrocyte progenitor cell (OPC) maturation, and reduced myelination of the white matter. Hyaluronan (HA) inhibits OPC maturation and complexes with the heavy chain (HC) of glycoprotein inter-α-inhibitor to form pathological HA (HC–HA complex), which exacerbates inflammation. Therefore, we hypothesized that IVH would result in accumulation of HA, and that either degradation of HA by hyaluronidase treatment or elimination of HCs from pathological HA by HA oligosaccharide administration would restore OPC maturation, myelination, and neurological function in survivors with IVH. To test these hypotheses, we used the preterm rabbit model of glycerol-induced IVH and analyzed autopsy samples from premature infants. We found that total HA levels were comparable in both preterm rabbit pups and human infants with and without IVH, but HA receptors—CD44, TLR2, TLR4—were elevated in the forebrain of both humans and rabbits with IVH. Hyaluronidase treatment of rabbits with IVH reduced CD44 and TLR4 expression, proinflammatory cytokine levels, and microglia infiltration. It also promoted OPC maturation, myelination, and neurological recovery. HC–HA and tumor necrosis factor-stimulated gene-6 were elevated in newborns with IVH; and depletion of HC–HA levels by HA oligosaccharide treatment reduced inflammation and enhanced myelination and neurological recovery in rabbits with IVH. Hence, hyaluronidase or HA oligosaccharide treatment represses inflammation, promotes OPC maturation, and restores myelination and neurological function in rabbits with IVH. These therapeutic strategies might improve the neurological outcome of premature infants with IVH. SIGNIFICANCE STATEMENT Approximately 12,000 premature infants develop IVH every year in the United States, and a large number of survivors with IVH develop cerebral palsy and cognitive deficits. The onset of IVH induces inflammation

  8. Preparation and characterization of 15N-enriched, size-defined heparan sulfate precursor oligosaccharides

    PubMed Central

    Sigulinsky, Crystal; Babu, Ponnusamy; Victor, Xylophone V.; Kuberan, Balagurunathan

    2009-01-01

    We report the preparation of size-defined [15N]N-acetylheparosan oligosaccharides from Escherichia coli-derived 15N-enriched N-acetylheparosan. Optimized growth conditions of E. coli in minimal media containing 15NH4Cl yielded [15N]N-acetylheparosan on a preparative scale. Depolymerization of [15N]N-acetylheparosan by heparitinase I yielded resolvable, even-numbered oligosaccharides ranging from disaccharide to icosaccharide. Anion-exchange chromatography-assisted fractionation afforded size-defined [15N]N-acetylheparosan oligosaccharides identifiable by ESI-TOFMS. These isotopically labeled oligosaccharides will prove to be valuable research tools for the chemoenzymatic synthesis of heparin and heparan sulfate oligosaccharides and for the study of their structural biology. PMID:19945695

  9. Assessing the effects of different prebiotic dietary oligosaccharides in sheep milk ice cream.

    PubMed

    Balthazar, C F; Silva, H L A; Vieira, A H; Neto, R P C; Cappato, L P; Coimbra, P T; Moraes, J; Andrade, M M; Calado, V M A; Granato, D; Freitas, M Q; Tavares, M I B; Raices, R S L; Silva, M C; Cruz, A G

    2017-01-01

    The objective of this study was to assess the effects of different prebiotic dietary oligosaccharides (inulin, fructo-oligosaccharide, galacto-oligossacaride, short-chain fructo-oligosaccharide, resistant starch, corn dietary oligosaccharide and polydextrose) in non-fat sheep milk ice cream processing through physical parameters, water mobility and thermal analysis. Overall, the fat replacement by dietary prebiotic oligosaccharides significantly decreased the melting time, melting temperature and the fraction and relaxation time for fat and bound water (T22) while increased the white intensity and glass transition temperature. The replacement of sheep milk fat by prebiotics in sheep milk ice cream constitutes an interesting option to enhance nutritional aspects and develop a functional food.

  10. Disruption and eradication of P. aeruginosa biofilms using nitric oxide-releasing chitosan oligosaccharides

    PubMed Central

    Reighard, Katelyn P.; Hill, David B.; Dixon, Graham A.; Worley, Brittany; Schoenfisch, Mark H.

    2015-01-01

    Biofilm disruption and eradication were investigated as a function of nitric oxide- (NO) releasing chitosan oligosaccharide dose with results compared to control (ie non-NO-releasing) chitosan oligosaccharides and tobramycin. Quantification of biofilm expansion/contraction and multiple-particle tracking microrheology were used to assess the structural integrity of the biofilm before and after antibacterial treatment. While tobramycin had no effect on the physical properties of the biofilm, NO-releasing chitosan oligosaccharides exhibited dose-dependent behavior with biofilm degradation. Control chitosan oligosaccharides increased biofilm elasticity, indicating that the scaffold may mitigate the biofilm disrupting power of nitric oxide somewhat. The results from this study indicate that nitric oxide-releasing chitosan oligosaccharides act as dual-action therapeutics capable of eradicating and physically disrupting P. aeruginosa biofilms. PMID:26610146

  11. [Separation and identification of oligosaccharides labeled with 3-amino-9-ethylcarbazole using high performance liquid chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry].

    PubMed

    Mou, Qing; Zhang, Ying; Huang, Linjuan; Wang, Zhongfu

    2009-01-01

    A pre-column derivatization method for the determination of oligosaccharides based ion a labeling reagent 3-amino-9-ethylcarbazole (AEC) was proposed. The enamines were generated by the reaction of the reducing ends of oligosaccharides and the primary amines of AEC, and then reduced to secondary amines by NaBH3CN, making oligosaccharides labeled by AEC. The derivatives were separated by reversed-phase high performance liquid chromatography (RP-HPLC), and then directly analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The HPLC separation was carried out on a Waters Symmetry C18 column (3.9 mm x 150 mm, 5 microm) with a gradient elution (acetonitrile and ammonium acetate as mobile phases at a flow rate of 1 mL/min) and ultraviolet detection at 254 nm. Under the optimized derivatization and HPLC conditions, the derivatized oligosaccharides were separated, and the derivatization with AEC increased the sensitivity of MS detection. The developed method for the analysis of oligosaccharides is satisfactory.

  12. Precision powder feeder

    DOEpatents

    Schlienger, M. Eric; Schmale, David T.; Oliver, Michael S.

    2001-07-10

    A new class of precision powder feeders is disclosed. These feeders provide a precision flow of a wide range of powdered materials, while remaining robust against jamming or damage. These feeders can be precisely controlled by feedback mechanisms.

  13. Asparagine-linked oligosaccharides on lutropin, follitropin, and thyrotropin: structural elucidation of the sulfated and sialylated oligosaccharides on bovine, ovine, and human pituitary glycoprotein hormones

    SciTech Connect

    Green, E.D.; Baenziger, J.U.

    1988-01-05

    The authors have elucidated the structures of the anionic asparagine-linked oligosaccharides present on the glycoprotein hormones lutropin (luteinizing hormone), follitropin (follicle-stimulating hormone), and thyrotropin (thyroid-stimulating hormone). Purified hormones, isolated from bovine, ovine, and human pituitaries, were digested with N-glycanase, and the released oligosaccharides were reduced with NaB(/sup 3/H)/sub 4/. The /sup 3/H-labeled oligosaccharides from each hormone were then fractionated by anion-exchange high performance liquid chromatography (HPLC) into populations differing in the number of sulfate and/or sialic acid moieties. The sulfated, sialylated, and sulfated/sialylated structures, which together comprised 67-90% of the asparagine-linked oligosaccharides on the pituitary glycoprotein hormones, were highly heterogeneous and displayed hormone- as well as animal species-specific features. A previously uncharacterized dibranched oligosaccharide, bearing one residue each of sulfate and sialic acid, was found on all of the hormones except bovine lutropin. In this study, they describe the purification and detailed structural characterizations of the sulfated, sialylated, and sulfated/sialylated oligosaccharides found on lutropin, follitropin, and thyrotropin from several animal species.

  14. Carbohydrate-deficient glycoprotein syndrome: not an N-linked oligosaccharide processing defect, but an abnormality in lipid-linked oligosaccharide biosynthesis?

    PubMed Central

    Powell, L D; Paneerselvam, K; Vij, R; Diaz, S; Manzi, A; Buist, N; Freeze, H; Varki, A

    1994-01-01

    The carbohydrate-deficient glycoprotein syndrome (CDGS) is a developmental disease associated with an abnormally high isoelectric point of serum transferrin. Carbohydrate analyses of this glycoprotein initially suggested a defect in N-linked oligosaccharide processing, although more recent studies indicate a defect in the attachment of these sugar chains to the protein. We studied both serum glycoproteins and fibroblast-derived [2-3H]mannose-labeled oligosaccharides from CDGS patients and normal controls. While there was a decrease in the glycosylation of serum glycoproteins of affected individuals, differences were not seen in either monosaccharide composition or oligosaccharide structures. The lectin-binding profiles of glycopeptides from [2-3H]-mannose-labeled fibroblasts were likewise indistinguishable. However, the incorporation of [2-3H]mannose into both glycoproteins and the dolichol-linked oligosaccharide precursor was significantly reduced. Thus, at least in some patients, CDGS is not due to a defect in processing of N-linked oligosaccharides, but rather to defective synthesis and transfer of nascent dolichol-linked oligosaccharide precursors. This abnormality could result in both a failure to glycosylate some sites on some proteins, as well as secondary abnormalities in overall glycoprotein processing and/or function. PMID:7962535

  15. Precision spectroscopy of Helium

    SciTech Connect

    Cancio, P.; Giusfredi, G.; Mazzotti, D.; De Natale, P.; De Mauro, C.; Krachmalnicoff, V.; Inguscio, M.

    2005-05-05

    Accurate Quantum-Electrodynamics (QED) tests of the simplest bound three body atomic system are performed by precise laser spectroscopic measurements in atomic Helium. In this paper, we present a review of measurements between triplet states at 1083 nm (23S-23P) and at 389 nm (23S-33P). In 4He, such data have been used to measure the fine structure of the triplet P levels and, then, to determine the fine structure constant when compared with equally accurate theoretical calculations. Moreover, the absolute frequencies of the optical transitions have been used for Lamb-shift determinations of the levels involved with unprecedented accuracy. Finally, determination of the He isotopes nuclear structure and, in particular, a measurement of the nuclear charge radius, are performed by using hyperfine structure and isotope-shift measurements.

  16. Assignment of the Stereochemistry and Anomeric Configuration of Sugars within Oligosaccharides Via Overlapping Disaccharide Ladders Using MSn

    NASA Astrophysics Data System (ADS)

    Konda, Chiharu; Londry, Frank A.; Bendiak, Brad; Xia, Yu

    2014-08-01

    A systematic approach is described that can pinpoint the stereo-structures (sugar identity, anomeric configuration, and location) of individual sugar units within linear oligosaccharides. Using a highly modified mass spectrometer, dissociation of linear oligosaccharides in the gas phase was optimized along multiple-stage tandem dissociation pathways (MSn, n = 4 or 5). The instrument was a hybrid triple quadrupole/linear ion trap mass spectrometer capable of high-efficiency bidirectional ion transfer between quadrupole arrays. Different types of collision-induced dissociation (CID), either on-resonance ion trap or beam-type CID could be utilized at any given stage of dissociation, enabling either glycosidic bond cleavages or cross-ring cleavages to be maximized when wanted. The approach first involves optimizing the isolation of disaccharide units as an ordered set of overlapping substructures via glycosidic bond cleavages during early stages of MSn, with explicit intent to minimize cross-ring cleavages. Subsequently, cross-ring cleavages were optimized for individual disaccharides to yield key diagnostic product ions ( m/ z 221). Finally, fingerprint patterns that establish stereochemistry and anomeric configuration were obtained from the diagnostic ions via CID. Model linear oligosaccharides were derivatized at the reducing end, allowing overlapping ladders of disaccharides to be isolated from MSn. High confidence stereo-structural determination was achieved by matching MSn CID of the diagnostic ions to synthetic standards via a spectral matching algorithm. Using this MSn ( n = 4 or 5) approach, the stereo-structures, anomeric configurations, and locations of three individual sugar units within two pentasaccharides were successfully determined.

  17. Interaction of the Heparin-Binding Consensus Sequence of β-Amyloid Peptides with Heparin and Heparin-Derived Oligosaccharides.

    PubMed

    Nguyen, Khanh; Rabenstein, Dallas L

    2016-03-10

    Alzheimer's disease (AD) is characterized by the presence of amyloid plaques in the AD brain. Comprised primarily of the 40- and 42-residue β-amyloid (Aβ) peptides, there is evidence that the heparan sulfate (HS) of heparan sulfate proteoglycans (HSPGs) plays a role in amyloid plaque formation and stability; however, details of the interaction of Aβ peptides with HS are not known. We have characterized the interaction of heparin and heparin-derived oligosaccharides with a model peptide for the heparin- and HS-binding domain of Aβ peptides (Ac-VHHQKLV-NH2; Aβ(12-18)), with mutants of Aβ(12-18), and with additional histidine-containing peptides. The nature of the binding interaction was characterized by NMR, binding constants and other thermodynamic parameters were determined by isothermal titration calorimetry (ITC), and relative binding affinities were determined by heparin affinity chromatography. The binding of Aβ(12-18) by heparin and heparin-derived oligosaccharides is pH-dependent, with the imidazolium groups of the histidine side chains interacting site-specifically within a cleft created by a trisaccharide sequence of heparin, the binding is mediated by electrostatic interactions, and there is a significant entropic contribution to the binding free energy as a result of displacement of Na(+) ions from heparin upon binding of cationic Aβ(12-18). The binding constant decreases as the size of the heparin-derived oligosaccharide decreases and as the concentration of Na(+) ion in the bulk solution increases. Structure-binding relationships characterized in this study are analyzed and discussed in terms of the counterion condensation theory of the binding of cationic peptides by anionic polyelectrolytes.

  18. Significance of galactinol and raffinose family oligosaccharide synthesis in plants

    PubMed Central

    Sengupta, Sonali; Mukherjee, Sritama; Basak, Papri; Majumder, Arun L.

    2015-01-01

    Abiotic stress induces differential expression of genes responsible for the synthesis of raffinose family of oligosaccharides (RFOs) in plants. RFOs are described as the most widespread D-galactose containing oligosaccharides in higher plants. Biosynthesis of RFOs begin with the activity of galactinol synthase (GolS; EC 2.4.1.123), a GT8 family glycosyltransferase that galactosylates myo-inositol to produce galactinol. Raffinose and the subsequent higher molecular weight RFOs (Stachyose, Verbascose, and Ajugose) are synthesized from sucrose by the subsequent addition of activated galactose moieties donated by Galactinol. Interestingly, GolS, the key enzyme of this pathway is functional only in the flowering plants. It is thus assumed that RFO synthesis is a specialized metabolic event in higher plants; although it is not known whether lower plant groups synthesize any galactinol or RFOs. In higher plants, several functional importance of RFOs have been reported, e.g., RFOs protect the embryo from maturation associated desiccation, are predominant transport carbohydrates in some plant families, act as signaling molecule following pathogen attack and wounding and accumulate in vegetative tissues in response to a range of abiotic stresses. However, the loss-of-function mutants reported so far fail to show any perturbation in those biological functions. The role of RFOs in biotic and abiotic stress is therefore still in debate and their specificity and related components remains to be demonstrated. The present review discusses the biology and stress-linked regulation of this less studied extension of inositol metabolic pathway. PMID:26379684

  19. The Cytosolic Oligosaccharide-Degrading Proteome of Butyrivibrio Proteoclasticus

    PubMed Central

    Dunne, Jonathan C.; Kelly, William J.; Leahy, Sinead C.; Li, Dong; Bond, Judy J.; Peng, Lifeng; Attwood, Graeme T.; Jordan, T. William

    2015-01-01

    The growth and productivity of ruminants depends on a complex microbial community found in their fore-stomach (rumen), which is able to breakdown plant polysaccharides and ferment the released sugars. Butyrivibrio proteoclasticus B316T is a Gram-positive polysaccharide-degrading, butyrate-producing bacterium that is present at high numbers in the rumen of animals consuming pasture or grass silage based diets. B316T is one of a small number of rumen fibrolytic microbes capable of efficiently degrading and utilizing xylan, as well as being capable of utilizing arabinose, xylose, pectin and starch. We have therefore carried out a proteomic analysis of B316T to identify intracellular enzymes that are implicated in the metabolism of internalized xylan. Three hundred and ninety four proteins were identified including enzymes that have potential to metabolize assimilated products of extracellular xylan digestion. Identified enzymes included arabinosidases, esterases, an endoxylanase, and β-xylosidase. The presence of intracellular debranching enzymes indicated that some hemicellulosic side-chains may not be removed until oligosaccharides liberated by extracellular digestion have been assimilated by the cells. The results support a model of extracellular digestion of hemicellulose to oligosaccharides that are then transported to the cytoplasm for further digestion by intracellular enzymes. PMID:28248275

  20. Subcellular localization of glycosidases and glycosyltransferases involved in the processing of N-linked oligosaccharides

    SciTech Connect

    Sturm, A.; Johnson, K.D.; Szumilo, T.; Elbein, A.D.; Chrispeels, M.J.

    1987-11-01

    Using isopycnic sucrose gradients, we have ascertained the subcellular location of several enzymes involved in the processing of the N-linked oligosaccharides of glycoproteins in developing cotyledons of the common bean, Phaseolus vulgaris. All are localized in the endoplasmic reticulum (ER) or Golgi complex as determined by co-sedimentation with the ER marker, NADH-cytochrome c reductase, or the Golgi marker, glucan synthase I. Glucosidase activity, which removes glucose residues from Glc/sub 3/Man/sub 9/(GlcNAc)/sub 2/, was found exclusively in the ER. All other processing enzymes, which act subsequent to the glucose trimming steps, are associates with Golgi. These include mannosidase I (removes 1-2 mannose residues from Man/sub 6-9/(GlcNAc)/sub 2/), mannosidase II (removes mannose residues from GlcNAcMan/sub 5/(GlcNAc)/sub 2/), and fucosyltransferase (transfers a fucose residue to the Asn-linked GlcNAc of appropriate glycans). The authors have previously reported the localization of two other glycan modifying enzymes (GlcNAc-transferase and xylosyltranferase activities) in the Golgi complex. Attempts at subfractionation of the Golgi fraction on shallow sucrose gradients yielded similar patterns of distribution for all the Golgi processing enzymes. Subfractionation on Percoll gradients resulted in two peaks of the Golgi marker enzyme inosine diphosphatase, whereas the glycan processing enzymes were all enriched in the peak of lower density. These results do not lend support to the hypothesis that N-linked oligosaccharide processing enzymes are associated with Golgi cisternae of different densities.

  1. The structural basis of oligosaccharide binding by rice BGlu1 beta-glucosidase.

    PubMed

    Chuenchor, Watchalee; Pengthaisong, Salila; Robinson, Robert C; Yuvaniyama, Jirundon; Svasti, Jisnuson; Cairns, James R Ketudat

    2011-01-01

    Rice BGlu1 β-glucosidase is an oligosaccharide exoglucosidase that binds to six β-(1→4)-linked glucosyl residues in its active site cleft. Here, we demonstrate that a BGlu1 E176Q active site mutant can be effectively rescued by small nucleophiles, such as acetate, azide and ascorbate, for hydrolysis of aryl glycosides in a pH-independent manner above pH5, consistent with the role of E176 as the catalytic acid-base. Cellotriose, cellotetraose, cellopentaose, cellohexaose and laminaribiose are not hydrolyzed by the mutant and instead exhibit competitive inhibition. The structures of the BGlu1 E176Q, its complexes with cellotetraose, cellopentaose and laminaribiose, and its covalent intermediate with 2-deoxy-2-fluoroglucoside were determined at 1.65, 1.95, 1.80, 2.80, and 1.90Å resolution, respectively. The Q176Nε was found to hydrogen bond to the glycosidic oxygen of the scissile bond, thereby explaining its high activity. The enzyme interacts with cellooligosaccharides through direct hydrogen bonds to the nonreducing terminal glucosyl residue. However, interaction with the other glucosyl residues is predominantly mediated through water molecules, with the exception of a direct hydrogen bond from N245 to glucosyl residue 3, consistent with the apparent high binding energy at this residue. Hydrophobic interactions with the aromatic sidechain of W358 appear to orient glucosyl residues 2 and 3, while Y341 orients glucosyl residues 4 and 5. In contrast, laminaribiose has its second glucosyl residue positioned to allow direct hydrogen bonding between its O2 and Q176 Oε and O1 and N245. These are the first GH1 glycoside hydrolase family structures to show oligosaccharide binding in the hydrolytic configuration.

  2. Reinforcement of frontal affinity chromatography for effective analysis of lectin-oligosaccharide interactions.

    PubMed

    Hirabayashi, J; Arata, Y; Kasai, K

    2000-08-25

    Frontal affinity chromatography is a method for quantitative analysis of biomolecular interactions. We reinforced it by incorporating various merits of a contemporary liquid chromatography system. As a model study, the interaction between an immobilized Caenorhabditis elegans galectin (LEC-6) and fluorescently labeled oligosaccharides (pyridylaminated sugars) was analyzed. LEC-6 was coupled to N-hydroxysuccinimide-activated Sepharose 4 Fast Flow (100 microm diameter), and packed into a miniature column (e.g., 10 x 4.0 mm, 0.126 ml). Twelve pyridylaminated oligosaccharides were applied to the column through a 2-ml sample loop, and their elution patterns were monitored by fluorescence. The volume of the elution front (V) determined graphically for each sample was compared with that obtained in the presence of an excess amount of hapten saccharide, lactose (V0); and the dissociation constant, Kd, was calculated according to the literature [K. Kasai, Y. Oda, M. Nishikawa, S. Ishii, J. Chromatogr. 376 (1986) 33]. This system also proved to be useful for an inverse confirmation; that is, application of galectins to an immobilized glycan column (in the present case, asialofetuin was immobilized on Sepharose 4 Fast Flow), and the elution profiles were monitored by fluorescence based on tryptophan. The relative affinity of various galectins for asialofetuin could be easily compared in terms of the extent of retardation. The newly constructed system proved to be extremely versatile. It enabled rapid (analysis time 12 min/cycle) and sensitive (20 nM for pyridylaminated derivatives, and 1 microg/ml for protein) analyses of lectin-carbohydrate interactions. It should become a powerful tool for elucidation of biomolecular interactions, in particular for functional analysis of a large number of proteins that should be the essential issues of post-genome projects.

  3. Xylo-Oligosaccharide Process Development, Composition, and Techno-Economic Analysis. Cooperative Research and Development Final Report, CRADA Number CRD-12-483

    SciTech Connect

    Shekiro, Joe; Elander, Richard

    2015-12-01

    The purpose of this cooperative work agreement between General Mills Inc. (GMI) and NREL is to determine the feasibility of producing a valuable food ingredient (xylo-oligosaccharides or XOS), a highly soluble fiber material, from agricultural waste streams, at an advantaged cost level relative to similar existing ingredients. The scope of the project includes pilot-scale process development (Task 1), compositional analysis (Task 2), and techno-economic analysis (Task 3).

  4. Precision GPS ephemerides and baselines

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Based on the research, the area of precise ephemerides for GPS satellites, the following observations can be made pertaining to the status and future work needed regarding orbit accuracy. There are several aspects which need to be addressed in discussing determination of precise orbits, such as force models, kinematic models, measurement models, data reduction/estimation methods, etc. Although each one of these aspects was studied at CSR in research efforts, only points pertaining to the force modeling aspect are addressed.

  5. MALDI Q-TOF CID MS for Diagnostic Ion Screening of Human Milk Oligosaccharide Samples

    PubMed Central

    Jovanović, Marko; Tyldesley-Worster, Richard; Pohlentz, Gottfried; Peter-Katalinić, Jasna

    2014-01-01

    Human milk oligosaccharides (HMO) represent the bioactive components of human milk, influencing the infant’s gastrointestinal microflora and immune system. Structurally, they represent a highly complex class of analyte, where the main core oligosaccharide structures are built from galactose and N-acetylglucosamine, linked by 1–3 or 1–4 glycosidic linkages and potentially modified with fucose and sialic acid residues. The core structures can be linear or branched. Additional structural complexity in samples can be induced by endogenous exoglycosidase activity or chemical procedures during the sample preparation. Here, we show that using matrix-assisted laser desorption/ionization (MALDI) quadrupole-time-of-flight (Q-TOF) collision-induced dissociation (CID) as a fast screening method, diagnostic structural information about single oligosaccharide components present in a complex mixture can be obtained. According to sequencing data on 14 out of 22 parent ions detected in a single high molecular weight oligosaccharide chromatographic fraction, 20 different oligosaccharide structure types, corresponding to over 30 isomeric oligosaccharide structures and over 100 possible HMO isomers when biosynthetic linkage variations were taken into account, were postulated. For MS/MS data analysis, we used the de novo sequencing approach using diagnostic ion analysis on reduced oligosaccharides by following known biosynthetic rules. Using this approach, de novo characterization has been achieved also for the structures, which could not have been predicted. PMID:24743894

  6. Synthesis and characterization of isomaltulose-derived oligosaccharides produced by transglucosylation reaction of Leuconostoc mesenteroides dextransucrase.

    PubMed

    Barea-Alvarez, Montserrat; Benito, Maria Teresa; Olano, Agustín; Jimeno, Maria Luisa; Moreno, F Javier

    2014-09-17

    This paper reports the efficient enzymatic synthesis of a homologous series of isomaltulose-derived oligosaccharides with degrees of polymerization ranging from 3 to 9 through the transglucosylation reaction using a dextransucrase from Leuconostoc mesenteroides B-512F. The total oligosaccharide yield obtained under optimal conditions was 41-42% (in weight with respect to the initial amount of isomaltulose) after 24-48 h of reaction. Nuclear magnetic resonance (NMR) structural characterization indicated that dextransucrase specifically transferred glucose moieties of sucrose to the C-6 of the nonreducing glucose residue of isomaltulose. Likewise, monitoring the progression of the content of each individual oligosaccharide indicated that oligosaccharide acceptor products of low molecular weight acted in turn as acceptors for further transglucosylation to yield oligosaccharides of a higher degree of polymerization. The produced isomaltulose-derived oligosaccharides can be considered as isomalto-oligosaccharides (IMOs) because they are linked by only α-(1→6) bonds. In addition, having isomaltulose as the core structure, these IMO-like structures could possess appealing bioactive properties that could find potential applications as functional food ingredients.

  7. Automated sample preparation facilitated by PhyNexus MEA purification system for oligosaccharide mapping of glycoproteins.

    PubMed

    Prater, Bradley D; Anumula, Kalyan R; Hutchins, Jeff T

    2007-10-15

    A reproducible high-throughput sample cleanup method for fluorescent oligosaccharide mapping of glycoproteins is described. Oligosaccharides are released from glycoproteins using PNGase F and labeled with 2-aminobenzoic acid (anthranilic acid, AA). A PhyNexus MEA system was adapted for automated isolation of the fluorescently labeled oligosaccharides from the reaction mixture prior to mapping by HPLC. The oligosaccharide purification uses a normal-phase polyamide resin (DPA-6S) in custom-made pipette tips. The resin volume, wash, and elution steps involved were optimized to obtain high recovery of oligosaccharides with the least amount of contaminating free fluorescent dye in the shortest amount of time. The automated protocol for sample cleanup eliminated all manual manipulations with a recycle time of 23 min. We have reduced the amount of excess AA by 150-fold, allowing quantitative oligosaccharide mapping from as little as 500 ng digested recombinant immunoglobulin G (rIgG). This low sample requirement allows early selection of a cell line with desired characteristics (e.g., oligosaccharide profile and high specific productivity) for the production of glycoprotein drugs. In addition, the use of Tecan or another robotic platform in conjunction with this method should allow the cleanup of 96 samples in 23 min, a significant decrease in the amount of time currently required to process such a large number of samples.

  8. Bovine milk as a source of functional oligosaccharides for improving human health.

    PubMed

    Zivkovic, Angela M; Barile, Daniela

    2011-05-01

    Human milk oligosaccharides are complex sugars that function as selective growth substrates for specific beneficial bacteria in the gastrointestinal system. Bovine milk is a potentially excellent source of commercially viable analogs of these unique molecules. However, bovine milk has a much lower concentration of these oligosaccharides than human milk, and the majority of the molecules are simpler in structure than those found in human milk. Specific structural characteristics of milk-derived oligosaccharides are crucial to their ability to selectively enrich beneficial bacteria while inhibiting or being less than ideal substrates for undesirable and pathogenic bacteria. Thus, if bovine milk products are to provide human milk-like benefits, it is important to identify specific dairy streams that can be processed commercially and cost-effectively and that can yield specific oligosaccharide compositions that will be beneficial as new food ingredients or supplements to improve human health. Whey streams have the potential to be commercially viable sources of complex oligosaccharides that have the structural resemblance and diversity of the bioactive oligosaccharides in human milk. With further refinements to dairy stream processing techniques and functional testing to identify streams that are particularly suitable for enriching beneficial intestinal bacteria, the future of oligosaccharides isolated from dairy streams as a food category with substantiated health claims is promising.

  9. Preparation and characterisation of the oligosaccharides derived from Chinese water chestnut polysaccharides.

    PubMed

    Wu, Sheng-Jun; Yu, Lin

    2015-08-15

    Hydrogen peroxide (H2O2) is a strong oxidant that cleaves glycosidic bonds in polysaccharides. In this study, the oligosaccharides were prepared by removing the starch from Chinese water chestnuts through hydrolysis using α-amylase and then hydrolysing the remaining polysaccharides with H2O2, during which the oligosaccharide yield was monitored. The yield of oligosaccharide was affected by reaction time, temperature, and H2O2 concentration. Extended reaction times, high temperatures, and high H2O2 concentrations decreased oligosaccharide yield. Under optimum conditions (i.e., reaction time of 4h, reaction temperature of 80°C, and 2.5% H2O2 concentration), the maximum oligosaccharide yield was 3.91%. The oligosaccharides derived from Chinese water chestnuts polysaccharides exhibited strong hydroxyl and 2,2-diphenyl-β-picrylhydrazyl radical scavenging activity when applied at a concentration of 100 μg/mL. The results indicate that the oligosaccharides derived from Chinese water chestnuts polysaccharides possessed good antioxidant properties and can be developed as a new dietary supplement and functional food.

  10. A precise new KLOE measurement of | with ISR events and determination of ππ contribution to a from threshold to 0.95 GeV

    NASA Astrophysics Data System (ADS)

    Venanzoni, G.; KLOE Collaboration

    2011-09-01

    The KLOE experiment at the DAΦNE ϕ-factory has performed a new precise measurement of the pion form factor using Initial State Radiation events, with photons emitted at large polar angle. This measurement extends the Mππ2 region covered by KLOE ISR measurements of the pion form factor down to the two pion production threshold. The value obtained in this measurement of the di-pion contribution to the muon anomalous magnetic moment confirms the discrepancy between the Standard Model evaluation for a and the experimental value measured by the (g-2) collaboration at BNL. A combination of this new result with the previous KLOE results allow to cover ˜ 70% of the leading order hadronic contribution to the muon anomaly with 1% total fractional error.

  11. Precise Magnetic Structures of Hard Ferromagnets of ND2FE14B Type as Determined at Low Temperature from Single Crystal Neutron Diffraction

    NASA Astrophysics Data System (ADS)

    Wolfers, P.; Bacmann, M.; Fruchart, D.

    2000-09-01

    The main constituent of the hard magnet materials Nd-Fe-B is the prototype of a new ferromagnet series, the Nd2Fe14B type (Space Group P42/nmm). Such compounds are characterised by high magnetocrystalline anisotropy parameters, those of rare earth origin being several times higher than the contribution of the iron subblattices. In many cases, these two contributions exhibit markedly different thermal behaviours, resulting in spin rotation phenomena or (and) lowering of the crystalline and the magnetic symmetry from the tetragonal high temperature state. Low temperature very precise studies on selected compounds of the series R2Fe14B with R = Nd, Ho, Er and Y, were undertaken by using neutron four circle diffractometry on single crystals. When temperature is lowered, the two first compounds exhibit a continuous spin reorientation within the [110] plane from the c-axis at high temperature towards an intermediate direction. The Er compound presents a first order transition around 350K where the resulting magnetisation first order rotates from the c-axis a high temperature to the a basal plane direction at low temperature. The last one compound remains c-easy axis in the whole temperature range. From our neutron diffraction experiments, lowering of the crystal symmetry to monoclinic (orthorhombic) space groups was precisely measured for the two first (third) samples. Besides marked deviations to collinearity affect the different sublattice magnetisations. Yet, these well marked phenomena have not been accounted for in the hundert experimental and theoretical analysis dedicated to the series. However, our results are in good agreement with a detailed 57Fe Mössbauer spectroscopy analysis of the Ho ternary hydrides.

  12. Precise determination of the deuteron spin structure at low to moderate Q2 with CLAS and extraction of the neutron contribution

    DOE PAGES

    Guler, N.; Fersch, R. G.; Kuhn, S. E.; ...

    2015-11-02

    In this study, we present the final results for the deuteron spin structure functions obtained from the full data set collected with Jefferson Lab's CLAS in 2000-2001. Polarized electrons with energies of 1.6, 2.5, 4.2 and 5.8 GeV were scattered from deuteron (15ND3) targets, dynamically polarized along the beam direction, and detected with CLAS. From the measured double spin asymmetry, the virtual photon absorption asymmetry Ad1 and the polarized structure function gd1 were extracted over a wide kinematic range (0.05 GeV2 < Q2 < 5 GeV2 and 0.9 GeV < W < 3 GeV). We use an unfolding procedure andmore » a parametrization of the corresponding proton results to extract from these data the polarized structure functions An1 and g1n of the (bound) neutron, which are so far unknown in the resonance region, W < 2 GeV. We compare our final results, including several moments of the deuteron and neutron spin structure functions, with various theoretical models and expectations as well as parametrizations of the world data. The unprecedented precision and dense kinematic coverage of these data can aid in future extractions of polarized parton distributions, tests of perturbative QCD predictions for the quark polarization at large x, a better understanding of quark-hadron duality, and more precise values for higher-twist matrix elements in the framework of the Operator Product Expansion.« less

  13. Precise determination of the deuteron spin structure at low to moderate Q2 with CLAS and extraction of the neutron contribution

    NASA Astrophysics Data System (ADS)

    Guler, N.; Fersch, R. G.; Kuhn, S. E.; Bosted, P.; Griffioen, K. A.; Keith, C.; Minehart, R.; Prok, Y.; Adhikari, K. P.; Adikaram, D.; Amaryan, M. J.; Anderson, M. D.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A.; Briscoe, W. J.; Brooks, W. K.; Bültmann, S.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Crabb, D.; Crede, V.; D'Angelo, A.; Dashyan, N.; Deur, A.; Djalali, C.; Dodge, G. E.; Dupre, R.; Alaoui, A. El; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Filippi, A.; Fleming, J. A.; Forest, T. A.; Garillon, B.; Garçon, M.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Golovatch, E.; Gothe, R. W.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Harrison, N.; Hattawy, M.; Hicks, K.; Ho, D.; Holtrop, M.; Hughes, S. M.; Hyde, C. E.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jo, H. S.; Joo, K.; Joosten, S.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuleshov, S. V.; Livingston, K.; Lu, H. Y.; Mayer, M.; MacGregor, I. J. D.; McKinnon, B.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Movsisyan, A.; Munoz Camacho, C.; Nadel-Turonski, P.; Net, L. A.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Pasyuk, E.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Simonyan, A.; Skorodumina, Iu.; Sokhan, D.; Sparveris, N.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Tian, Ye; Tkachenko, S.; Ungaro, M.; Voutier, E.; Walford, N. K.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2015-11-01

    We present the final results for the deuteron spin structure functions obtained from the full data set collected in 2000-2001 with Jefferson Lab's continuous electron beam accelerator facility (CEBAF) using the CEBAF large acceptance spectrometer (CLAS). Polarized electrons with energies of 1.6, 2.5, 4.2, and 5.8 GeV were scattered from deuteron (15ND3 ) targets, dynamically polarized along the beam direction, and detected with CLAS. From the measured double-spin asymmetry, the virtual photon absorption asymmetry A1d and the polarized structure function g1d were extracted over a wide kinematic range (0.05 GeV2precision and dense kinematic coverage of these data can aid in future extractions of polarized parton distributions, tests of perturbative QCD predictions for the quark polarization at large x , a better understanding of quark-hadron duality, and more precise values for higher-twist matrix elements in the framework of the operator product expansion.

  14. Calcium-Activated SK Channels Influence Voltage-Gated Ion Channels to Determine the Precision of Firing in Globus Pallidus Neurons

    PubMed Central

    Deister, Christopher A.; Chan, C. Savio; Surmeier, D. James; Wilson, Charles J.

    2012-01-01

    Globus pallidus (GP) neurons fire rhythmically in the absence of synaptic input, suggesting that they may encode their inputs as changes in the phase of their rhythmic firing. Action potential afterhyperpolarization (AHP) enhances precision of firing by ensuring that the ion channels recover from inactivation by the same amount on each cycle. Voltage-clamp experiments in slices showed that the longest component of the GP neuron’s AHP is blocked by apamin, a selective antagonist of calcium-activated SK channels. Application of 100 nm apamin also disrupted the precision of firing in perforated-patch and cell-attached recordings. SK channel blockade caused a small depolarization in spike threshold and made it more variable, but there was no reduction in the maximal rate of rise during an action potential. Thus, the firing irregularity was not caused solely by a reduction in voltage-gated Na+ channel availability. Subthreshold voltage ramps triggered a large outward current that was sensitive to the initial holding potential and had properties similar to the A-type K+ current in GP neurons. In numerical simulations, the availability of both Na+ and A-type K+ channels during autonomous firing were reduced when SK channels were removed, and a nearly equal reduction in Na+ and K+ subthreshold-activated ion channel availability produced a large decrease in the neuron’s slope conductance near threshold. This change made the neuron more sensitive to intrinsically generated noise. In vivo, this change would also enhance the sensitivity of GP neurons to small synaptic inputs. PMID:19571136

  15. Primary structure determination of five sialylated oligosaccharides derived from bronchial mucus glycoproteins of patients suffering from cystic fibrosis. The occurrence of the NeuAc alpha(2----3)Gal beta(1----4)[Fuc alpha(1----3)] GlcNAc beta(1----.) structural element revealed by 500-MHz 1H NMR spectroscopy.

    PubMed

    Lamblin, G; Boersma, A; Klein, A; Roussel, P; van Halbeek, H; Vliegenthart, J F

    1984-07-25

    The structure of sialylated carbohydrate units of bronchial mucins obtained from cystic fibrosis patients was investigated by 500-MHz 1H NMR spectroscopy in conjunction with sugar analysis. After subjecting the mucins to alkaline borohydride degradation, sialylated oligosaccharide-alditols were isolated by anion-exchange chromatography and fractionated by high performance liquid chromatography. Five compounds could be obtained in a rather pure state; their structures were established as the following: A-1, NeuAc alpha(2----3)Gal beta(1----4) [Fuc alpha(1----3)]GlcNAc beta(1----3)Gal-NAc-ol; A-2, NeuAc alpha(2----3)Gal beta(1----4)GlcNAc beta(1----6)-[GlcNAc beta (1----3)]GalNAc-o1; A-3, NeuAc alpha(2----3)Gal beta-(1----4)[Fuc alpha(1----3)]GlcNAc beta(1----3)Gal beta(1----3) GalNAc-o1; A-4, NeuAc alpha(2----3)Gal beta(1----4)[Fuc alpha(1----3)]Glc-NAc NAc beta(1----6)[GlcNAc beta(1----3)]GalNAc-o1; A-6,NeuAc alpha-(2----3) Gal beta(1----4)[Fuc alpha(1----3)]GlcNAc beta(1----6)[Gal beta-(1----4) GlcNAc beta(1----3)]GalNAc-o1. The simultaneous presence of sialic acid in alpha(2----3)-linkage to Gal and fucose in alpha(1----3)-linkage to GlcNAc of the same N-acetyllactosamine unit could be adequately proved by high resolution 1H NMR spectroscopy. This sequence constitutes a novel structural element for mucins.

  16. Comparative Genomics of the Aeromonadaceae Core Oligosaccharide Biosynthetic Regions.

    PubMed

    Forn-Cuní, Gabriel; Merino, Susana; Tomás, Juan M

    2017-02-28

    Lipopolysaccharides (LPSs) are an integral part of the Gram-negative outer membrane, playing important organizational and structural roles and taking part in the bacterial infection process. In Aeromonas hydrophila, piscicola, and salmonicida, three different genomic regions taking part in the LPS core oligosaccharide (Core-OS) assembly have been identified, although the characterization of these clusters in most aeromonad species is still lacking. Here, we analyse the conservation of these LPS biosynthesis gene clusters in the all the 170 currently public Aeromonas genomes, including 30 different species, and characterise the structure of a putative common inner Core-OS in the Aeromonadaceae family. We describe three new genomic organizations for the inner Core-OS genomic regions, which were more evolutionary conserved than the outer Core-OS regions, which presented remarkable variability. We report how the degree of conservation of the genes from the inner and outer Core-OS may be indicative of the taxonomic relationship between Aeromonas species.

  17. Applications of unnatural oligosaccharide biosynthesis to selective drug delivery

    SciTech Connect

    Yarema, K.J.; Mahal, L.K.; Bertozzi, C.R. |

    1997-12-31

    Cell surface antigens are attractive targets for the selective delivery of toxins to diseased cells. Most efforts toward the development of cell-specific drug targeting agents have focused on the use of monoclonal antibodies that recognize a particular antigen, an approach that suffers from severe limitations. We have recently demonstrated that unnatural epitopes can be displayed on cells using the biosynthetic pathways for cell-surface oligosaccharides. This discovery has now been extended to the development of a novel strategy for selective drug targeting. We installed ketone groups on cells through unnatural sialic acid biosynthesis, and selectively modified the cells with biotinamidocaproyl hydrazide under physiological conditions. Synthetic ricin-avidin conjugates killed the biotinylated cells with remarkable selectivity. Applications of this and related approaches to anti-cancer therapy will be presented.

  18. Breast Milk Oligosaccharides: Structure-Function Relationships in the Neonate

    PubMed Central

    Smilowitz, Jennifer T.; Lebrilla, Carlito B.; Mills, David A.; German, J. Bruce; Freeman, Samara L.

    2015-01-01

    In addition to providing complete postnatal nutrition, breast milk is a complex biofluid that delivers bioactive components for the growth and development of the intestinal and immune systems. Lactation is a unique opportunity to understand the role of diet in shaping the intestinal environment including the infant microbiome. Of considerable interest is the diversity and abundance of milk glycans that are energetically costly for the mammary gland to produce yet indigestible by infants. Milk glycans comprise free oligosaccharides, glycoproteins, glycopeptides, and glycolipids. Emerging technological advances are enabling more comprehensive, sensitive, and rapid analyses of these different classes of milk glycans. Understanding the impact of inter- and intraindividual glycan diversity on function is an important step toward interventions aimed at improving health and preventing disease. This review discusses the state of technology for glycan analysis and how specific structure-function knowledge is enhancing our understanding of early nutrition in the neonate. PMID:24850388

  19. Recognition of human milk oligosaccharides by bacterial exotoxins.

    PubMed

    El-Hawiet, Amr; Kitova, Elena N; Klassen, John S

    2015-08-01

    The affinities of the most abundant oligosaccharides found in human milk for four bacterial exotoxins (from Vibrio cholerae and pathogenic Escherichia coli) were quantified for the first time. Association constants (Ka) for a library of 20 human milk oligosaccharides (HMOs) binding to Shiga toxin type 2 holotoxin (Stx2) and the B subunit homopentamers of cholera toxin, heat-labile toxin and Shiga toxin type 1 (CTB5, HLTB5 and Stx1B5) were measured at 25°C and pH 7 using the direct electrospray ionization mass spectrometry assay. Notably, all four bacterial toxins bind to a majority of the HMOs tested and five of the HMOs (2'-fucosyllactose, lacto-N-tetraose, lacto-N-fucopentaose I, lacto-N-fucopentaose II and lacto-N-fucopentaose III) are ligands for all four toxins. These five HMOs are also reported to bind to other bacterial toxins (e.g. toxin A and toxin B of Clostridium difficile). In all cases, the HMO affinities (apparent Ka) are relatively modest (≤15,000 M(-1)). However, at the high concentrations of HMOs typically ingested by infants, a significant fraction of these toxins, if present, is expected to be bound to HMOs. Binding measurements carried out with 2'-fucosyllactose or lacto-N-fucopentaose I, together with a high-affinity ligand based on the native carbohydrate receptor, revealed that all four toxins possess HMO-binding sites that are distinct from those of the native receptors, although evidence of competitive binding was found for lacto-N-fucopentaose I with Stx2 and 2'-fucosyllactose and lacto-N-fucopentaose I with HLTB5. Taken together, the results of this study suggest that, while HMOs are expected to bind extensively to these bacterial toxins, it is unlikely that HMO binding will effectively inhibit their interactions with their cellular receptors.

  20. Human milk oligosaccharides: Every baby needs a sugar mama

    PubMed Central

    Bode, Lars

    2012-01-01

    Human milk oligosaccharides (HMOs) are a family of structurally diverse unconjugated glycans that are highly abundant in and unique to human milk. Originally, HMOs were discovered as a prebiotic “bifidus factor” that serves as a metabolic substrate for desired bacteria and shapes an intestinal microbiota composition with health benefits for the breast-fed neonate. Today, HMOs are known to be more than just “food for bugs”. An accumulating body of evidence suggests that HMOs are antiadhesive antimicrobials that serve as soluble decoy receptors, prevent pathogen attachment to infant mucosal surfaces and lower the risk for viral, bacterial and protozoan parasite infections. In addition, HMOs may modulate epithelial and immune cell responses, reduce excessive mucosal leukocyte infiltration and activation, lower the risk for necrotizing enterocolitis and provide the infant with sialic acid as a potentially essential nutrient for brain development and cognition. Most data, however, stem from in vitro, ex vivo or animal studies and occasionally from association studies in mother–infant cohorts. Powered, randomized and controlled intervention studies will be needed to confirm relevance for human neonates. The first part of this review introduces the pioneers in HMO research, outlines HMO structural diversity and describes what is known about HMO biosynthesis in the mother's mammary gland and their metabolism in the breast-fed infant. The second part highlights the postulated beneficial effects of HMO for the breast-fed neonate, compares HMOs with oligosaccharides in the milk of other mammals and in infant formula and summarizes the current roadblocks and future opportunities for HMO research. PMID:22513036

  1. Study on the applicability of a precise, accurate method for rapid evaluation of engine and lubricant performance. [determination of wear metal in used lubricating oils

    NASA Technical Reports Server (NTRS)

    Kinard, J. T.

    1975-01-01

    The development of a procedure for obtaining data related to wear metal determinations in used lubricants is discussed. The procedure makes it possible to obtain rapid, simultaneous determinations of a number of wear metals at levels of parts per thousand to low parts per billion using a small amount of sample. The electrode assembly and instrumentation used in the process are described. Samples of data obtained from tests conducted under controlled conditions are tabulated.

  2. Development and Validation of a Precise, Single HPLC Method for the Determination of Tolperisone Impurities in API and Pharmaceutical Dosage Forms

    PubMed Central

    Raju, Thummala Veera Raghava; Seshadri, Raja Kumar; Arutla, Srinivas; Mohan, Tharlapu Satya Sankarsana Jagan; Rao, Ivaturi Mrutyunjaya; Nittala, Someswara Rao

    2013-01-01

    A novel, sensitive, stability-indicating HPLC method has been developed for the quantitative estimation of Tolperisone-related impurities in both bulk drugs and pharmaceutical dosage forms. Effective chromatographic separation was achieved on a C18 stationary phase with a simple mobile phase combination delivered in a simple gradient programme, and quantitation was by ultraviolet detection at 254 nm. The mobile phase consisted of a buffer and acetonitrile delivered at a flow rate 1.0 ml/min. The buffer consisted of 0.01 M potassium dihydrogen phosphate with the pH adjusted to 8.0 by using diethylamine. In the developed HPLC method, the resolution between Tolperisone and its four potential impurities was found to be greater than 2.0. Regression analysis showed an R value (correlation coefficient) of greater than 0.999 for the Tolperisone impurities. This method was capable of detecting all four impurities of Tolperisone at a level of 0.19 μg/mL with respect to the test concentration of 1000 μg/mL for a 10 µl injection volume. The tablets were subjected to the stress conditions of hydrolysis, oxidation, photolysis, and thermal degradation. Considerable degradation was found to occur in base hydrolysis, water hydrolysis, and oxidation. The stress samples were assayed against a qualified reference standard and the mass balance was found to be close to 100%. The established method was validated and found to be linear, accurate, precise, specific, robust, and rugged. PMID:23641333

  3. Development and Validation of a Precise, Single HPLC Method for the Determination of Tolperisone Impurities in API and Pharmaceutical Dosage Forms.

    PubMed

    Raju, Thummala Veera Raghava; Seshadri, Raja Kumar; Arutla, Srinivas; Mohan, Tharlapu Satya Sankarsana Jagan; Rao, Ivaturi Mrutyunjaya; Nittala, Someswara Rao

    2013-01-01

    A novel, sensitive, stability-indicating HPLC method has been developed for the quantitative estimation of Tolperisone-related impurities in both bulk drugs and pharmaceutical dosage forms. Effective chromatographic separation was achieved on a C18 stationary phase with a simple mobile phase combination delivered in a simple gradient programme, and quantitation was by ultraviolet detection at 254 nm. The mobile phase consisted of a buffer and acetonitrile delivered at a flow rate 1.0 ml/min. The buffer consisted of 0.01 M potassium dihydrogen phosphate with the pH adjusted to 8.0 by using diethylamine. In the developed HPLC method, the resolution between Tolperisone and its four potential impurities was found to be greater than 2.0. Regression analysis showed an R value (correlation coefficient) of greater than 0.999 for the Tolperisone impurities. This method was capable of detecting all four impurities of Tolperisone at a level of 0.19 μg/mL with respect to the test concentration of 1000 μg/mL for a 10 µl injection volume. The tablets were subjected to the stress conditions of hydrolysis, oxidation, photolysis, and thermal degradation. Considerable degradation was found to occur in base hydrolysis, water hydrolysis, and oxidation. The stress samples were assayed against a qualified reference standard and the mass balance was found to be close to 100%. The established method was validated and found to be linear, accurate, precise, specific, robust, and rugged.

  4. Regulation of the protein glycosylation pathway in yeast: structural control of N-linked oligosaccharide elongation

    SciTech Connect

    Gopal, P.K.; Ballou, C.E.

    1987-12-01

    The yeast Saccharomyces cerevisiae X2180 strain with the mnn1 mnn2 mnn9 mutations, all of which affect mannoprotein glycosylation, synthesizes N-linked oligosaccharides. Membrane fractions from the mnn1 mnn2 and mnn1 mnn2 mnn9 mutants are equally effective in catalyzing transfer from GDP-(/sup 3/H)mannose to add mannose in both ..cap alpha..1 ..-->.. 2 and ..cap alpha..1 ..-->.. 6 linkages to an oligosaccharide. Neither membrane preparation can utilize the homologous mnn1 mnn2 mnn9 oligosaccharide as an acceptor. Thus, addition of the ..cap alpha..1 ..-->.. 2-linked mannose side chain to the terminal ..cap alpha..1 ..-->.. 6-linked mannose in oligosaccharides of the mnn9 mutant inhibits the elongation reaction and may serve as an important structural control of mannoprotein glycosylation. The mnn9 mutation also increases the transit time for invertase secretion, meaning that this mutation could affect the processing machinery in the Golgi apparatus.

  5. (Pseudo)amide-linked oligosaccharide mimetics: molecular recognition and supramolecular properties

    PubMed Central

    Ortega-Caballero, Fernando; Ortiz Mellet, Carmen; García Fernández, José M

    2010-01-01

    Summary Oligosaccharides are currently recognised as having functions that influence the entire spectrum of cell activities. However, a distinct disadvantage of naturally occurring oligosaccharides is their metabolic instability in biological systems. Therefore, much effort has been spent in the past two decades on the development of feasible routes to carbohydrate mimetics which can compete with their O-glycosidic counterparts in cell surface adhesion, inhibit carbohydrate processing enzymes, and interfere in the biosynthesis of specific cell surface carbohydrates. Such oligosaccharide mimetics are potential therapeutic agents against HIV and other infections, against cancer, diabetes and other metabolic diseases. An efficient strategy to access this type of compounds is the replacement of the glycosidic linkage by amide or pseudoamide functions such as thiourea, urea and guanidine. In this review we summarise the advances over the last decade in the synthesis of oligosaccharide mimetics that possess amide and pseudoamide linkages, as well as studies focussing on their supramolecular and recognition properties. PMID:20485602

  6. The hydrolyzation of collagen by fucoidan oligosaccharide's complex with CeIV

    NASA Astrophysics Data System (ADS)

    Xu, Jiachao; Gao, Xin; Zhang, Zhaohui; Li, Zhaojie; Huo, Lihua; Xue, Changhu

    2006-04-01

    Fucoidan is such a polysaccharide that its hydroxies are easy to combine with lanthanons ion (CeIV) to form complex. This work obtained the complexes of three fucoidan oligosaccharides with different molecular weights F1 (>5000), F2 (1000 5000) and F3 (<1000) by hydrolyzing Oligosaccharide collagen with sulfuric acid. It is found that the fucoidan oligosaccharide F3 can form complex with more CeIV than F1 and F2. Hydrolyzing collagen with the complex was carried out to produce amino acid and peptides. All the three fucoidan oligosaccharide complexes with CeIV (F1, F2, F3) can catalyze by the artificial hydrolytic enzyme, and the activity of the complex of F3 is the highest.

  7. Energy-Dependent Electron Activated Dissociation of Metal-Adducted Permethylated Oligosaccharides

    PubMed Central

    Yu, Xiang; Huang, Yiqun; Lin, Cheng; Costello, Catherine E.

    2013-01-01

    The effects of varying the electron energy and cationizing agents on electron activated dissociation (ExD) of metal-adducted oligosaccharides were explored, using permethylated maltoheptaose as the model system. Across the examined range of electron energy, the metal-adducted oligosaccharide exhibited several fragmentation processes, including electron capture dissociation (ECD) at low energies, hot-ECD at intermediate energies, and electronic excitation dissociation (EED) at high energies. The dissociation threshold depended on the metal charge carrier(s), whereas the types and sequence spans of product ions were influenced by the metal-oligosaccharide binding pattern. Theoretical modeling contributed insight into the metal-dependent behavior of carbohydrates during low-energy ECD. When ExD was applied to a permethylated high mannose N-linked glycan, EED provided more structural information than either collision-induced dissociation (CID) or low-energy ECD, thus demonstrating its potential for oligosaccharide linkage analysis. PMID:22881449

  8. Identification and characterisation of water and alkali soluble oligosaccharides from hazelnut skin (Corylus avellana L.).

    PubMed

    Montella, Rosa; Coïsson, Jean Daniel; Travaglia, Fabiano; Locatelli, Monica; Bordiga, Matteo; Meyrand, Mickael; Barile, Daniela; Arlorio, Marco

    2013-10-15

    Hazelnut skins are a good example of agricultural by-product with the potential to become a valuable source of functional ingredients. In this work, the fibre from hazelnut skins was extracted by using water and alkali solution and characterised by a suite of analytical tools (MALDI-FTICR, nano LC-Chip-Q-ToF and gas chromatography). Over thirty complex free oligosaccharides, composed mainly of galacturonic acid and N-acetylgalactosamine, were characterised for the first time in the present study. Their concentration ranged between 16 and 34mg per g of extract. The oligosaccharides isolated from this agricultural by-product are mainly hexose oligosaccharides (potentially galacto-oligosaccharides,) and xyloglucans. The identified composition could justify the bioactive activity of the extracts, namely prebiotic activity, previously demonstrated.

  9. Protocrustal evolution of the Nuvvuagittuq Supracrustal Belt as determined by high precision zircon Lu-Hf and U-Pb isotope data

    NASA Astrophysics Data System (ADS)

    Augland, Lars Eivind; David, Jean

    2015-10-01

    The Nuvvuagittuq Supracrustal Belt (NSB) in northern Quebec, Canada, represents one of the oldest known crustal fragments preserved in the Earth's crust. Its age has, however, been disputed and different authors present crustal formation ages varying from ca. 3.8 Ga to 4.4 Ga (e.g. O'Neil et al., 2012; Guitreau et al., 2013). Here we report new high precision U-Pb geochronological and coupled Lu-Hf isotope data from zircons that reveal the age of the NSB and provide new constraints on the source rocks to this piece of early crust. Two rocks have been analysed, a felsic schist, interpreted to represent a volcanite, and a mylonitic tonalite that is intrusive into the NSB. The felsic schist was emplaced at 3771 + 5 / - 3 Ma, dating the formation of the NSB. The Lu-Hf model age indicates that the parental melt to the felsic schist was extracted from the mantle at this age or within a few tens of million years, but no more than 300 m.y., before its extrusion. This mantle extraction age provides an absolute maximum age for the NSB, but the most probable age of its protocrust is ca. 3.8 Ga. The mylonitic tonalite was emplaced at 3667 + 3 / - 1 Ma. Its Lu-Hf isotopic composition reveals the presence of an older crustal component than that of the NSB, requiring that its precursor melt formed from a Hadean source that was older than the NSB. Based on recent models for Archean TTG formation, we propose that this source represents re-melted Hadean hydrated crust that must have been translated below the NSB at ca. 3667 Ma.

  10. Precise Countersinking Tool

    NASA Technical Reports Server (NTRS)

    Jenkins, Eric S.; Smith, William N.

    1992-01-01

    Tool countersinks holes precisely with only portable drill; does not require costly machine tool. Replaceable pilot stub aligns axis of tool with centerline of hole. Ensures precise cut even with imprecise drill. Designed for relatively low cutting speeds.

  11. Structure of four acidic oligosaccharides from the jelly coat surrounding the eggs of Xenopus laevis.

    PubMed

    Plancke, Y; Wieruszeski, J M; Alonso, C; Boilly, B; Strecker, G

    1995-07-15

    Novel acidic oligosaccharides were released by reductive beta-elimination from the jelly coat eggs of the Anuran Xenopus laevis. According to the structural analysis of these oligosaccharide-alditols, the following structures are proposed: [sequence: see text] where Kdn, 3-deoxy-D-glycero-D-galactononulosonic acid. These results confirm the species specificity of the glycanic structures present in the secretion of amphibian oviducts, and may form the basis of a specific egg-sperm recognition process.

  12. Precision cleaning apparatus and method

    DOEpatents

    Schneider, T.W.; Frye, G.C.; Martin, S.J.

    1998-01-13

    A precision cleaning apparatus and method are disclosed. The precision cleaning apparatus includes a cleaning monitor further comprising an acoustic wave cleaning sensor such as a quartz crystal microbalance (QCM), a flexural plate wave (FPW) sensor, a shear horizontal acoustic plate mode (SH--APM) sensor, or a shear horizontal surface acoustic wave (SH--SAW) sensor; and measurement means connectable to the sensor for measuring in-situ one or more electrical response characteristics that vary in response to removal of one or more contaminants from the sensor and a workpiece located adjacent to the sensor during cleaning. Methods are disclosed for precision cleaning of one or more contaminants from a surface of the workpiece by means of the cleaning monitor that determines a state of cleanliness and any residual contamination that may be present after cleaning; and also for determining an effectiveness of a cleaning medium for removing one or more contaminants from a workpiece. 11 figs.

  13. Precision cleaning apparatus and method

    DOEpatents

    Schneider, Thomas W.; Frye, Gregory C.; Martin, Stephen J.

    1998-01-01

    A precision cleaning apparatus and method. The precision cleaning apparatus includes a cleaning monitor further comprising an acoustic wave cleaning sensor such as a quartz crystal microbalance (QCM), a flexural plate wave (FPW) sensor, a shear horizontal acoustic plate mode (SH--APM) sensor, or a shear horizontal surface acoustic wave (SH--SAW) sensor; and measurement means connectable to the sensor for measuring in-situ one or more electrical response characteristics that vary in response to removal of one or more contaminants from the sensor and a workpiece located adjacent to the sensor during cleaning. Methods are disclosed for precision cleaning of one or more contaminants from a surface of the workpiece by means of the cleaning monitor that determines a state of cleanliness and any residual contamination that may be present after cleaning; and also for determining an effectiveness of a cleaning medium for removing one or more contaminants from a workpiece.

  14. Precision agricultural systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Precision agriculture is a new farming practice that has been developing since late 1980s. It has been variously referred to as precision farming, prescription farming, site-specific crop management, to name but a few. There are numerous definitions for precision agriculture, but the central concept...

  15. Separation of Oligosaccharides from Lotus Seeds via Medium-pressure Liquid Chromatography Coupled with ELSD and DAD

    PubMed Central

    Lu, Xu; Zheng, Zhichang; Miao, Song; Li, Huang; Guo, Zebin; Zhang, Yi; Zheng, Yafeng; Zheng, Baodong; Xiao, Jianbo

    2017-01-01

    Lotus seeds were identified by the Ministry of Public Health of China as both food and medicine. One general function of lotus seeds is to improve intestinal health. However, to date, studies evaluating the relationship between bioactive compounds in lotus seeds and the physiological activity of the intestine are limited. In the present study, by using medium pressure liquid chromatography coupled with evaporative light-scattering detector and diode-array detector, five oligosaccharides were isolated and their structures were further characterized by electrospray ionization-mass spectrometry and gas chromatography-mass spectrometry. In vitro testing determined that LOS3-1 and LOS4 elicited relatively good proliferative effects on Lactobacillus delbrueckii subsp. bulgaricus. These results indicated a structure-function relationship between the physiological activity of oligosaccharides in lotus seeds and the number of probiotics applied, thus providing room for improvement of this particular feature. Intestinal probiotics may potentially become a new effective drug target for the regulation of immunity. PMID:28276495

  16. Early intestinal development and mucin transcription in the young poult with probiotic and mannan oligosaccharide prebiotic supplementation.

    PubMed

    Hutsko, S L; Meizlisch, K; Wick, M; Lilburn, M S

    2016-05-01

    Alternative and adjunctive approaches to decreasing the use of dietary antibiotics are becoming popular areas of study. Supplemental probiotics (commensal microbes) and prebiotics (indigestible complex carbohydrates) are 2 dietary approaches to facilitating the intestinal colonization of beneficial bacteria to compete with potential pathogens, thus creating a healthy mucosal environment. The intestinal mucosa is composed of mucin glycoproteins, which play a key role in preventing the attachment of pathogenic bacteria. At hatch, the neonatal turkey intestine is relatively aseptic and vulnderable to bacterial colonization by both commensal and pathogenic microbes. In the current study, we determined the transcription of MUC2, the primary mucin protein produced by goblet cells within the small intestine, and we also measured intestinal morphology immediately post-hatch through d 11. Poults were fed a conventional starter diet, the starter diet supplemented with one of 2 commercial probiotics (A, B), or a commercial mannan oligosaccharide. MUC2 transcription increased from d zero to d 4 post-hatch (P< 0.05), but there was no effect of probiotic or prebiotic supplementation. Villus height and villus area both increased with Probiotic B and mannan oligosaccharide supplementation (P<0.05) and there was a significant d X treatment interaction effect for crypt depth (P=0.007). These results suggest that probiotic and prebiotic supplementation can positively alter the intestinal microenvironment.

  17. Towards molecular modeling of the impact of heparin-derived oligosaccharides on hIFN-γ binding

    NASA Astrophysics Data System (ADS)

    Lilkova, E.; Petkov, P.; Ilieva, N.; Litov, L.

    2015-10-01

    Human interferon gamma (hIFN-γ) is an important signalling molecule, which plays a key role in the formation and modulation of immune response. The role of the cytokine C-termini in the formation of a complex with the extracellular receptor is still controversial due to the lack of structural information about this domain. Moreover, the C-termini are also responsible for the high affinity interaction of hIFN-γ with the glycosaminoglicans heparan sulfate and heparin. This interaction can drastically change the properties and behaviour of the protein. We performed molecular dynamics simulations in order to model the structure of the hIFN-γ C-terminal part and the interaction of the cytokine with heparin-derived oligosaccharides. For this purpose we reconstructed the missing C-terminal amino acid residues and performed folding simulations to determine their conformation. In order to simulate the interaction with heparin-like fragments, we developed CHARMM 36 compatible force field for the sulfamate anion group that is present in the glucosamine sugar to complete the heparin and heparan sulfate force field. The new topology and parameters reproduce the available experimental structural properties of heparin-like fragments. The simulations show that the oligosaccharides quickly bind the IFN-γ C-termini and reduce their solvent accessible surface area.

  18. Capillary electrophoresis separation of a mixture of chitin and chitosan oligosaccharides derivatized using a modified fluorophore conjugation procedure.

    PubMed

    Beaudoin, Marie-Eve; Gauthier, Julie; Boucher, Isabelle; Waldron, Karen C

    2005-08-01

    A capillary electrophoresis (CE) method was developed for the simultaneous analysis of small chitin and chitosan oligosaccharides. For detection purposes, the oligomers were derivatized with 8-aminopyrene-1,3,6-trisulfonic acid (APTS), a well known fluorophore for oligosaccharides analysis. The detection was performed by laser-induced fluorescence (LIF) with an argon ion laser having an excitation wavelength of 488 nm and with emission monitored at 520 nm. Derivatization parameters such as reaction time and conditions were examined. Separation conditions were also varied by testing a range of buffer pHs and concentrations. The best conditions were found using an 80 mM borate buffer at pH 8.4. This CE-LIF optimized method was used for the analysis of an enzymatically produced oligo-chitosan sample composed of a complex mixture and having an average degree of polymerization of 3.7 monomer units and 80% deacetylation. The oligo-chitosan sample was treated with a chitin deacetylase-like enzyme, the products were derivatized with APTS, and then analyzed without purification. The goal was to determine whether the deacetylase-like enzyme could increase the extent of deacetylation of the oligo-chitosan sample.

  19. A comparative study of free oligosaccharides in the milk of domestic animals.

    PubMed

    Albrecht, Simone; Lane, Jonathan A; Mariño, Karina; Al Busadah, Khalid A; Carrington, Stephen D; Hickey, Rita M; Rudd, Pauline M

    2014-04-14

    The present study was conducted to obtain a comprehensive overview of oligosaccharides present in the milk of a variety of important domestic animals including cows, goats, sheep, pigs, horses and dromedary camels. Using an analytical workflow that included ultra-performance liquid chromatography-hydrophilic interaction liquid chromatography with fluorescence detection coupled to quadrupole time-of-flight MS, detailed oligosaccharide libraries were established. The partial or full characterisation of the neutral/fucosylated, phosphorylated and sialylated structures was facilitated by sequencing with linkage- and sugar-specific exoglycosidases. Relative peak quantification of the 2-aminobenzamide-labelled oligosaccharides provided additional information. Milk from domestic animals contained a much larger variety of complex oligosaccharides than was previously assumed, and thirteen of these structures have been identified previously in human milk. The direct comparison of the oligosaccharide mixtures reflects their role in the postnatal maturation of different types of gastrointestinal systems, which, in this way, are prepared for certain post-weaning diets. The potential value of animal milk for the commercial extraction of oligosaccharides to be used in human and animal health is highlighted.

  20. Synthesis and Fermentation Properties of Novel Galacto-Oligosaccharides by β-Galactosidases from Bifidobacterium Species

    PubMed Central

    Rabiu, Bodun A.; Jay, Andrew J.; Gibson, Glenn R.; Rastall, Robert A.

    2001-01-01

    β-Galactosidase enzymes were extracted from pure cultures of Bifidobacterium angulatum, B. bifidum BB-12, B. adolescentis ANB-7, B. infantis DSM-20088, and B. pseudolongum DSM-20099 and used in glycosyl transfer reactions to synthesize oligosaccharides from lactose. At a lactose concentration of 30% (wt/wt) oligosaccharide yields of 24.7 to 47.6% occurred within 7 h. Examination of the products by thin-layer chromatography and methylation analysis revealed distinct product derived spectra from each enzyme. These were found to be different to that of Oligomate 55, a commercial prebiotic galacto-oligosaccharide. Fermentation testing of the oligosaccharides showed an increase in growth rate, compared to Oligomate 55, with products derived from B. angulatum, B. bifidum, B. infantis, and B. pseudolongum. However B. adolescentis had a lower growth rates on its oligosaccharide compared with Oligomate 55. Mixed culture testing of the B. bifidum BS-4 oligosaccharide showed that the overall prebiotic effect was equivalent to that of Oligomate 55. PMID:11375159

  1. Lipid-Linked Oligosaccharides in Membranes Sample Conformations That Facilitate Binding to Oligosaccharyltransferase

    PubMed Central

    Kern, Nathan R.; Lee, Hui Sun; Wu, Emilia L.; Park, Soohyung; Vanommeslaeghe, Kenno; MacKerell, Alexander D.; Klauda, Jeffery B.; Jo, Sunhwan; Im, Wonpil

    2014-01-01

    Lipid-linked oligosaccharides (LLOs) are the substrates of oligosaccharyltransferase (OST), the enzyme that catalyzes the en bloc transfer of the oligosaccharide onto the acceptor asparagine of nascent proteins during the process of N-glycosylation. To explore LLOs’ preferred location, orientation, structure, and dynamics in membrane bilayers of three different lipid types (dilauroylphosphatidylcholine, dimyristoylphosphatidylcholine, and dioleoylphosphatidylcholine), we have modeled and simulated both eukaryotic (Glc3-Man9-GlcNAc2-PP-Dolichol) and bacterial (Glc1-GalNAc5-Bac1-PP-Undecaprenol) LLOs, which are composed of an isoprenoid moiety and an oligosaccharide, linked by pyrophosphate. The simulations show no strong impact of different bilayer hydrophobic thicknesses on the overall orientation, structure, and dynamics of the isoprenoid moiety and the oligosaccharide. The pyrophosphate group stays in the bilayer head group region. The isoprenoid moiety shows high flexibility inside the bilayer hydrophobic core, suggesting its potential role as a tentacle to search for OST. The oligosaccharide conformation and dynamics are similar to those in solution, but there are preferred interactions between the oligosaccharide and the bilayer interface, which leads to LLO sugar orientations parallel to the bilayer surface. Molecular docking of the bacterial LLO to a bacterial OST suggests that such orientations can enhance binding of LLOs to OST. PMID:25418169

  2. Precise measurement of planeness.

    PubMed

    Schulz, G; Schwider, J

    1967-06-01

    Interference methods are reviewed-particularly those developed at the German Academy of Sciences in Berlin-with which the deviations of an optically flat surface from the ideal plane can be measured with a high degree of exactness. One aid to achieve this is the relative methods which measure the differences in planeness between two surfaces. These are then used in the absolute methods which determine the absolute planeness of a surface. This absolute determination can be effected in connection with a liquid surface, or (as done by the authors) only by suitable evaluation of relative measurements between unknown plates in various positional combinations. Experimentally, one uses two- or multiple-beam interference fringes of equal thickness(1) or of equal inclination. The fringes are observed visually, scanned, or photographed, and in part several wavelengths or curves of equal density (Aquidensiten) are employed. The survey also brings the following new methods: a relative method, where, with the aid of fringes of superposition, the fringe separation is subdivided equidistantly thus achieving an increase of measuring precision, and an absolute method which determines the deviations of a surface from ideal planeness along arbitrary central sections, without a liquid surface, from four relative interference photographs.

  3. Application of Metabolic 13C Labeling in Conjunction with High-Field Nuclear Magnetic Resonance Spectroscopy for Comparative Conformational Analysis of High Mannose-Type Oligosaccharides

    PubMed Central

    Kamiya, Yukiko; Yanagi, Kotaro; Kitajima, Toshihiko; Yamaguchi, Takumi; Chiba, Yasunori; Kato, Koichi

    2013-01-01

    High mannose-type oligosaccharides are enzymatically trimmed in the endoplasmic reticulum, resulting in various processing intermediates with exposed glycotopes that are recognized by a series of lectins involved in glycoprotein fate determination in cells. Although recent crystallographic data have provided the structural basis for the carbohydrate recognition of intracellular lectins, atomic information of dynamic oligosaccharide conformations is essential for a quantitative understanding of the energetics of carbohydrate–lectin interactions. Carbohydrate NMR spectroscopy is useful for characterizing such conformational dynamics, but often hampered by poor spectral resolution and lack of recombinant techniques required to produce homogeneous glycoforms. To overcome these difficulties, we have recently developed a methodology for the preparation of a homogeneous high mannose-type oligosaccharide with 13C labeling using a genetically engineered yeast strain. We herein successfully extended this method to result in the overexpression of 13C-labeled Man9GlcNAc2 (M9) with a newly engineered yeast strain with the deletion of four genes involved in N-glycan processing. This enabled high-field NMR analyses of 13C-labeled M9 in comparison with its processing product lacking the terminal mannose residue ManD2. Long-range NOE data indicated that the outer branches interact with the core in both glycoforms, and such foldback conformations are enhanced upon the removal of ManD2. The observed conformational variabilities might be significantly associated with lectins and glycan-trimming enzymes. PMID:24970159

  4. Isolation of reducing oligosaccharide chains from the chondroitin/dermatan sulfate-protein linkage region and preparation of analytical probes by fluorescent labeling with 2-aminobenzamide.

    PubMed

    Sakaguchi, H; Watanabe, M; Ueoka, C; Sugiyama, E; Taketomi, T; Yamada, S; Sugahara, K

    2001-01-01

    The glycosaminoglycan (GAG)-protein linkage regions of various proteoglycans share the common tetrasaccharide GlcA-Gal-Gal-Xyl-attached to Ser residues in the core proteins. In previous analysis we demonstrated unique modifications by epimerization, sulfation and phosphorylation of the component sugars. Here we developed a sensitive analytical method for the linkage region oligosaccharides to detect or monitor structural variations and changes. This will be useful for investigation of their biological roles, which are largely unknown, but they have been implicated in biosynthesis. A variety of linkage region-derived hexasaccharides was first prepared as reducing sugar chains from peptide chondroitin/dermatan sulfate of whale cartilage, shark cartilage, and bovine aorta by means of chondroitinase digestion in conjunction with beta-elimination in the absence of reducing reagents, but involving a mild alkali, 0.5 M LiOH, at 4 degrees C to prevent peeling reactions. The structures of these oligosaccharides were determined by the combination of HPLC, enzymatic digestion, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry, and (1)H NMR spectroscopy, which revealed eleven different hexasaccharides including a novel structure, DeltaHexAalpha1-3GalNAcbeta1-4IdoAalpha1-3Gal(4-O-sulfate)beta1-3Galbeta1-4Xyl (DeltaHexA and IdoA represent unsaturated hexuronic acid and L-iduronic acid, respectively). These oligosaccharides were labeled with a fluorophore, 2-aminobenzamide, to prepare analytical probes using the recently developed procedure [Kinoshita and Sugahara (1999) Anal. Biochem. 269, 367-378]. The fluorophore-tagged hexasacharides of low picomoles were well separated by HPLC and successfully analyzed by MALDI-TOF mass spectrometry. The principle of the method should be applicable to the analysis of the linkage region oligosaccharides derived from heparin and heparan sulfate as well.

  5. Precise determination of photon emission probabilities for the main X- and gamma-rays of 226Ra in equilibrium with daughters.

    PubMed

    Morel, J; Sepman, S; Rasko, M; Terechtchenko, E; Delgado, J U

    2004-01-01

    Within the context of a joint project between VNIIM (D.I. Mendeleyev Institute for Metrology) and LNHB (Laboratoire National Henri Becquerel), special 226Ra sources were prepared by VNIIM in order to determine as accurately as possible the absolute photon emission probabilities for the main X- and gamma-rays following the decay of 226Ra and daughters. The main purpose of this work was to supplement a previous joint study by Laboratorio Nacional de Metrologia das Radiaçoes Ionizantes (LNMRI) and LNHB to determine their relative values. Some specific point sources were produced for alpha-spectrometry measurements that were undertaken at VNIIM and also for gamma-ray spectrometry studies at VNIIM and LNHB. The 226Ra activity for the gamma-spectrometric sources was measured relative to the alpha-spectrometric sources by comparing the counts of the main gamma-rays. The total uncertainty of the activity for these sources was 0.2% (k = 1). Using calibrated germanium detectors, several X- and gamma-ray spectra were analyzed to determine the absolute photon emission probabilities of 226Ra in radioactive equilibrium with daughters. The results are presented and compared to other published values.

  6. Asparagine-linked sugar chains of glycoproteins in calf thymocyte plasma membrane. Isolation and fractionation of oligosaccharides liberated by hydrazinolysis.

    PubMed

    Yoshima, H; Takasaki, S; Kobata, A

    1980-07-01

    The plasma membrane glycoproteins of calf thymocytes were converted to glycopeptides by exhaustive pronase digestion. Glycopeptides with asparagine-linked sugar chains were separated from those with mucine-type sugar chains by Bio-Gel P-10 column chromatography. The asparagine-linked sugar chains were released as oligosaccharides from the peptide moiety by hydrazinolysis and labeled by reduction with NaB[3H]4. The radioactive oligosaccharides were fractionated into fifteen acidic components and ten neutral components by combination of paper electrophoresis and Bio-Gel P-4 column chromatography. The acidic nature of all fifteen acidic components can be ascribed to their N-acetylneuraminic acid residues. The Bio-Gel P-4 column chromatographic patterns of the neutral oligosaccharide fraction and of the neutral fraction obtained on sialidase treatment of the pooled acidic oligosaccharide fraction were totally different, indicating that the acidic oligosaccharides are not simple sialyl derivatives of the neutral oligosaccharides.

  7. Mass spectrometric detection of multiple extended series of neutral highly fucosylated N-acetyllactosamine oligosaccharides in human milk

    NASA Astrophysics Data System (ADS)

    Pfenninger, Anja; Chan, Shiu-Yung; Karas, Michael; Finke, Berndt; Stahl, Bernd; Costello, Catherine E.

    2008-12-01

    Complex mixtures of high-molecular weight fractions of pooled neutral human milk oligosaccharides (obtained via gel permeation chromatography) have been investigated. The subfractions were each permethylated and analyzed by high-resolution mass spectrometry, using matrix-assisted laser desorption/ionization (MALDI)-Fourier transform ion cyclotron resonance (FTICR) mass spectrometry, in order to investigate their oligosaccharide compositions. The obtained spectra reveal that human milk contains more complex neutral oligosaccharides than have been described previously; the data show that these oligosaccharides can be highly fucosylated, and that their poly-N-acetyllactosamine cores are substituted with up to 10 fucose residues on an oligosaccharide that has 7-N-acetyllactosamine units. This is the first report of the existence in human milk of this large range of highly fucosylated oligosaccharides which possess novel, potentially immunologically active structures.

  8. Distribution of nuclear bomb Pu in Nishiyama area, Nagasaki, estimated by accurate and precise determination of 240Pu/239Pu ratio in soils.

    PubMed

    Yoshida, S; Muramatsu, Y; Yamazaki, S; Ban-Nai, T

    2007-01-01

    Plutonium isotopes in forest soils collected in Nishiyama area, Nagasaki, were successfully determined by high resolution inductively coupled plasma mass spectrometry after the treatment with a microwave decomposition system. The (240)Pu/(239)Pu atom ratios observed in the samples in the Nishiyama area were obviously lower than the range of the global fallout. The low ratios (minimum 0.032) observed in Nishiyama area indicated the influence of detonation of the Pu nuclear weapon in 1945. Since the area is contaminated also by global fallout, the (240)Pu/(239)Pu atom ratio can be more sensitive indicator of bomb-derived Pu than Pu activity concentration.

  9. Nutritional value of soybean meal produced from conventional, high-protein, or low-oligosaccharide varieties of soybeans and fed to broiler chicks.

    PubMed

    Baker, K M; Utterback, P L; Parsons, C M; Stein, H H

    2011-02-01

    Three experiments were conducted to determine the feeding value to broiler chicks of soybean meal (SBM) produced from high-protein (SBM-HP), low-oligosaccharide (SBM-LO), or conventional (SBM-CV) varieties of soybeans. The 3 SBM contained 54.9, 53.6, and 47.5% CP, respectively. The standardized digestibility (SDD) of amino acids (AA) in the 3 ingredients was measured using a precision-fed rooster assay with cecectomized Single Comb White Leghorn roosters. Results indicated that the SDD of AA was not different among the 3 sources of SBM, with the exception that the SDD of Lys in SBM-HP tended to be greater (P = 0.07) than that in SBM