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1

10.7 cm-Solar Radio Flux and Ionospheric Temperatures.  

National Technical Information Service (NTIS)

Electron and ion temperatures, derived from backscatter spectra, are examined during the current rising phase of solar activity. There is a strong positive correlation between the 10.7 cm-solar radio flux and night-time ion and electron temperatures, the ...

K. K. Mahajan

1967-01-01

2

10.7-cm Microwave Observations of AR 5395 and Related Terrestrial Effects.  

National Technical Information Service (NTIS)

The 10.7 cm flux patrols in Canada recorded 4 Great Bursts (peaks greater than 500 sfu) during the disk passage of AR 5395 in March 1989. The Great Bursts of 16 and 17 March were simple events of great amplitude and with half-life durations of only severa...

V. Gaizauskas T. J. Hughes K. F. Tapping

1989-01-01

3

The 10.7-cm microwave observations of AR 5395 and related terrestrial effects  

NASA Technical Reports Server (NTRS)

The 10.7 cm flux patrols in Canada recorded 4 Great Bursts (peaks greater than 500 sfu) during the disk passage of AR 5395 in March 1989. The Great Bursts of 16 and 17 March were simple events of great amplitude and with half-life durations of only several minutes. Earlier Great Bursts, originating on 6 March towards the NE limb and on 10 March closer to the central meridian, belong to an entirely different category of event. Each started with a very strong impulsive event lasting just minutes. After an initial recovery, however, the emission climbed back to level as greater or greater than the initial impulsive burst. The events of 6 and 10 March stayed above the Great Burst threshold for at least 100 minutes. The second component of long duration in these cases is associated with Type 4 continuum emission and thus very likely with CMEs. Major geomagnetic disturbances did not occur as a result of the massive complex event of 6 March or the two simple but strong events of 16 and 17 March. But some 55 hours after the peak in the long-enduring burst of 10 March, a storm began which qualifies as the fourth strongest geomagnetic storm in Canada since 1932. The vertical component of the earth's field measured during the storm by a fluxgate magnetometer at a station in Manitoba is presented. Within a minute of the sudden commencement of this storm, a series of breakdowns began in the transmission system of Hydro-Quebec which resulted in a total loss of power, on a bitterly cold winter's day, for at least 10 hours. The loss of power provoked an enormous outcry from the public resulting in the power utilities being more receptive to the need to monitor solar as well as geomagnetic activity.

Gaizauskas, V.; Hughes, T. J.; Tapping, K. F.

1989-01-01

4

The 10.7-cm microwave observations of AR 5395 and related terrestrial effects  

NASA Astrophysics Data System (ADS)

The 10.7 cm flux patrols in Canada recorded 4 Great Bursts (peaks greater than 500 sfu) during the disk passage of AR 5395 in March 1989. The Great Bursts of 16 and 17 March were simple events of great amplitude and with half-life durations of only several minutes. Earlier Great Bursts, originating on 6 March towards the NE limb and on 10 March closer to the central meridian, belong to an entirely different category of event. Each started with a very strong impulsive event lasting just minutes. After an initial recovery, however, the emission climbed back to level as greater or greater than the initial impulsive burst. The events of 6 and 10 March stayed above the Great Burst threshold for at least 100 minutes. The second component of long duration in these cases is associated with Type 4 continuum emission and thus very likely with CMEs. Major geomagnetic disturbances did not occur as a result of the massive complex event of 6 March or the two simple but strong events of 16 and 17 March. But some 55 hours after the peak in the long-enduring burst of 10 March, a storm began which qualifies as the fourth strongest geomagnetic storm in Canada since 1932. The vertical component of the earth's field measured during the storm by a fluxgate magnetometer at a station in Manitoba is presented. Within a minute of the sudden commencement of this storm, a series of breakdowns began in the transmission system of Hydro-Quebec which resulted in a total loss of power, on a bitterly cold winter's day, for at least 10 hours. The loss of power provoked an enormous outcry from the public resulting in the power utilities being more receptive to the need to monitor solar as well as geomagnetic activity.

Gaizauskas, V.; Hughes, T. J.; Tapping, K. F.

5

The Solar Radio Flux on 10.7cm as the best index for Space Weather long-term Prediction  

Microsoft Academic Search

. The Solar Radio Flux on 10.7cm was observed since more than 60 years ago till today at Ottawa, Canada. The daily value of 10.7cm solar flux showed a very good correlation with solar activity than the sunspot number Rz. The space weather is affected by the electromagnetic radiation come from the solar corona (X-ray and gamma-rays). Also, it is

Mosalam Shaltout; Rr. Ramy Mawad; Mohamed Youssef

2008-01-01

6

Ionospheric evidence for a nonlinear relationship between the solar e.u.v. and 10.7 cm fluxes during an intense solar cycle  

Microsoft Academic Search

Results obtained from an analysis of the ionospheric electron content (IEC) data collected at several stations in the Northern Hemisphere during December 1980-December 1985, when the 10.7 cm solar flux index (F10.7) varied from 66 to 303, are presented. Diurnal maximum IEC value IEC(max) increases linearly with F10.7, as expected, for values of F10.7 less than about 200; at higher

N. Balan; G. J. Bailey; B. Jayachandran

1993-01-01

7

Multi-technique Analysis of the Solar 10.7 cm Radio Flux Time-Series in Relation to Predictability  

NASA Astrophysics Data System (ADS)

We studied the predictability of the 10.7 cm solar radio flux by using stationary and non-stationary time-series analysis techniques of fractal theory to find the correlation exponent, the spectral exponent, the Hurst exponent, and the fluctuation exponent of the time series. The Hurst exponent was determined, from which the fractal dimension and consequently the predictability was evaluated. The results suggest that stationary methods of analysis yield inconsistent result, that is, amongst the four techniques used, the values of the exponents show great disparity. While two of the techniques, namely the auto-correlation function analysis and the spectral analysis, indicate long-term positive correlation, the other two methods, specifically the Hurst rescaled range-analysis and the fluctuation analysis, clearly exhibit the anti-correlated nature of the time series. The two non-stationary methods, that is, the discrete wavelet transform and the centered moving-average analysis, yielded values of the Hurst exponent that are indicative of positive correlation, of persistent behavior, and also showed that the time series is predictable to a certain extent.

Ghosh, Oindrilla; Ghosh, Tanushree; Chatterjee, T. N.

2014-06-01

8

Ionospheric evidence for a nonlinear relationship between the solar e.u.v. and 10.7 cm fluxes during an intense solar cycle  

NASA Astrophysics Data System (ADS)

Results obtained from an analysis of the ionospheric electron content (IEC) data collected at several stations in the Northern Hemisphere during December 1980-December 1985, when the 10.7 cm solar flux index (F10.7) varied from 66 to 303, are presented. Diurnal maximum IEC value IEC(max) increases linearly with F10.7, as expected, for values of F10.7 less than about 200; at higher values of F10.7, contrary to expectation, IEC(max) saturates at all stations. The observed variation of IEC(max) is interpreted as convincing ionospheric evidence for a nonlinear relationship between solar e.u.v. and 10.7 cm fluxes during intense solar cycles. Variation of the e.u.v. flux obtained from the latest version of the SERF2 solar e.u.v. flux model for the intense solar cycle 21 agrees with this interpretation. Lyman-alpha and He I equivalent width data, measured during the same period as the IEC observations and used as independent data sets in the solar e.u.v. flux model, also show nonlinear variations with F10.7.

Balan, N.; Bailey, G. J.; Jayachandran, B.

1993-02-01

9

Changed Relation between Solar 10.7-cm Radio Flux and some Activity Indices which describe the Radiation at Different Altitudes of Atmosphere during Cycles 21-23  

NASA Astrophysics Data System (ADS)

The correlation coefficients of the linear regression of six solar indices versus 10.7 cm radio flux F 10.7 were analysed in solar cycles 21, 22 and 23. We also analysed the interconnection between these indices and F 10.7 with help of approximation by polynomials of second order. The indices we have studied in this paper are: the relative sunspot numbers - SSN, 530.3 nm coronal line flux - F 530, the total solar irradiance - TSI, Mg II 280 nm core-to-wing ratio UV-index, the Flare Index - FI and the counts of flares. In most cases the regressions of these solar indices vs. F 10.7 are close to the linear regression except the moments of time near the minimums and maximums of the 11-year activity. For the linear regressions, we found that correlation coefficients K corr(t) for the solar indices vs. F 10.7 and SSN dropped to their minimum values twice during each 11-year cycle.

Bruevich, E. A.; Bruevich, V. V.; Yakunina, G. V.

2014-04-01

10

The Effect of Relative Sunspot Numbers, Solar Flare Numbers and Variable Component of 10.7 CM Solar Flux on The Seasonal Variation of 6300 Å Line Intensity at Calcutta  

NASA Astrophysics Data System (ADS)

The paper presents the seasonal variation of 6300 Å line intensity at Calcutta with relative sunspot number, solar flare number and variable component of 10.7 cm solar flux. A study has been made and important results have been obtained which are as follows.

Midya, S. K.; Chattopadhyay, R.; Pal, C. M.

1997-04-01

11

Variations of Solar Irradiance, 10.7 cm Radio Flux, He I 10830 Å Equivalent Width, and Global Magnetic Field Intensity and Their Relation to Large-Scale Solar Magnetic Field Structure  

Microsoft Academic Search

Variations of total solar irradiance, 10.7 cm radio emission, the Hei 10830 Ú equivalent width and the solar magnetic field flux measured for the entire Sun are compared with variations of the energy index of the global solar magnetic field and the index of the effective solar multipole for years 1979–1992. It is shown that photospheric radiation and that generated

E. V. Ivanov; V. N. Obridko; I. V. Ananyev

1998-01-01

12

Design of a 10**36 CM-2 S-1 Super-B Factory  

SciTech Connect

Parameters have been studied for a high luminosity e{sup +}e{sup -} collider operating at the Upsilon 4S that would deliver a luminosity of 1 to 4 x 10{sup 36}/cm{sup 2}/s. This collider, called a Super-B Factory, would use a combination of linear collider and storage ring techniques. In this scheme an electron beam and a positron beam are stored in low-emittance damping rings similar to those designed for a Linear Collider (LC) or the next generation light source. A LC style interaction region is included in the ring to produce sub-millimeter vertical beta functions at the collision point. A large crossing angle (+/- 24 mrad) is used at the collision point to allow beam separation. A crab-waist scheme is used to reduce the hourglass effect and restore peak luminosity. Beam currents of 1.8 A at 4 x 7 GeV in 1251 bunches can produce a luminosity of 10{sup 36}/cm{sup 2}/s with upgrade possibilities. Such a collider would produce an integrated luminosity of about 10,000 fb{sup -1} (10 ab{sup -1}) in a running year (10{sup 7} sec) at the {gamma}(4S) resonance. Further possibilities include having longitudinally polarized e- at the IR and operating at the J/Psi and Psi beam energies.

Biagini, M.E.; Boni, R.; Boscolo, M.; Demma, T.; Drago, A.; Guiducci, S.; Raimondi, P.; Tomassini, S.; Zobov, M.; /Frascati; Bertsche, Kirk J.; Novokhatski, A.; Seeman, J.; Sullivan, M.; Wienands, U.; Wittmer, W.; /SLAC; Bettoni, S.; /CERN; Paoloni, E.; Marchiori, G.; /Pisa U.; Bogomyagkov, A.; Koop, I.; Levichev, E.; /Novosibirsk, IYF

2011-10-24

13

Radio emission from the quiet sun and local sources at wavelengths 5, 10.7, 12, and 95 cm from observations of the January 4, 2011 eclipse in Crimea  

NASA Astrophysics Data System (ADS)

The radio radii of the Sun at wavelengths of 5, 10.7, 12, and 95 cm have been determined from eclipse observations as R5 ? (1.0 ± 0.015) R ?, R 10,12 = (1.05 ± 0.003) R ?, and R 95 = (1.2 ± 0.02) R ?. The bright-ness temperatures of quiet solar disk areas at these wavelengths have turned out to be Td 5 = (22 ± 2) × 103, Td 10 = (44 ± 3) × 103, Td 12 = (47 ± 3) × 103, and Td 95 = (1000 ± 30) × 103 K. There were local sources of radio emission with angular sizes from 1.9 to 2.4 arcmin and brightness temperatures from 80 × 103 to 1.75 × 106 K above sunspot groups at short wavelengths of 5, 10.7, and 12 cm. The radio flux from the local sources at 95 cm turned out to be below the detection threshold of 1.0 × 10-22 W m-2 Hz-1. Comparison of the values obtained with the results of observations of another eclipse on August 1, 2008, occurred at the epoch of minimum of the 11-year solar cycle has shown that the radio radius of the Sun at 10.7 and 12 cm increased from 1.016 R ? to 1.05 ± 0.003 R ?, the height of the emitting layer at these wavelengths moved from 11 × 103 km to (30 ± 7) × 103 K, and the brightness temperature of the quiet Sun rose from (35.8 ± 0.4) × 103 K to (44 ± 3) × 103 K at 10.7 cm and from (37.3 ± 0.4) × 103 K to (47 ± 3) × 103 K at 12 cm. Consequently, the parameters of the solar atmosphere changed noticeably in 2 years in connection with the beginning of the new solar cycle 24. The almost complete absence of local sources at the longest wavelength of 95 cm suggests that the magnetic fields of the sunspot groups on January 4, 2011, were weak and did not penetrate to the height from where their emission could originate. If this property is inherent in most sunspot groups of cycle 24, then it can be responsible for its low flare activity.

Yurovsky, Yu. F.

2012-06-01

14

Nondispersive hole transport in a polyfluorene copolymer with a mobility of 0.01 cm2 V-1 s-1  

NASA Astrophysics Data System (ADS)

The hole mobility in the fluorene copolymer poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)) diphenylamine)] (TFB) was measured using the time-of-flight technique. Transport was found to be nondispersive throughout the temperature range between 220 and 350 K, indicating the absence of intrinsic traps in this material. At room temperature, TFB shows a hole mobility of 0.01 cm2 V-1 s-1, with a weak field dependence. The hole mobility is independent of sample thickness in the range between 0.9 and 6.4 ?m. These results are in agreement with a narrow transport manifold, with a width of 65.9+/-0.5 meV.

Fong, H. H.; Papadimitratos, Alexios; Malliaras, George G.

2006-10-01

15

Electron-deficient poly(p-phenylene vinylene) provides electron mobility over 1 cm² V(-1) s(-1) under ambient conditions.  

PubMed

Poly(p-phenylene vinylene) derivatives (PPVs) are one of the most widely investigated p-type polymers in organic electronics. PPVs generally exhibit electron mobilities lower than 10(-4) cm(2) V(-1) s(-1), thus hindering their applications in high-performance polymer field-effect transistors and organic photovoltaics. Herein, we design and synthesize a novel electron-deficient PPV derivative, benzodifurandione-based PPV (BDPPV). This new PPV derivative displays high electron mobilities up to 1.1 cm(2) V(-1) s(-1) under ambient conditions (4 orders of magnitude higher than those of other PPVs), because it overcomes common defects in PPVs, such as conformational disorder, weak interchain interaction, and a high LUMO level. BDPPV represents the first polymer that can transport electrons over 1 cm(2) V(-1) s(-1) under ambient conditions. PMID:23675890

Lei, Ting; Dou, Jin-Hu; Cao, Xiao-Yu; Wang, Jie-Yu; Pei, Jian

2013-08-21

16

Record High Electron Mobility of 6.3 cm(2) V(-1) s(-1) Achieved for Polymer Semiconductors Using a New Building Block.  

PubMed

A new electron acceptor building block, 3,6-di(pyridin-2-yl)pyrrolo[3,4-c ]pyrrole-1,4(2H ,5H)-dione (DBPy), is used to construct a donor-acceptor polymer, PDBPyBT. This polymer exhibits a strong self-assembly capability, to form highly crystalline and oriented thin films with a short ?-? stacking distance of 0.36 nm. PDBPyBT shows ambipolar charge-transport performance in organic thin-film transistors, reaching a record high electron-mobility value of 6.30 cm(2) V(-1) s(-1) . PMID:24623497

Sun, Bin; Hong, Wei; Yan, Zhuangqing; Aziz, Hany; Li, Yuning

2014-05-01

17

X-ray detection with Micromegas with background levels below 10-6keV-1cm-2s-1  

NASA Astrophysics Data System (ADS)

Micromegas detectors are an optimum technological choice for the detection of low energy x-rays. The low background techniques applied to these detectors yielded remarkable background reductions over the years, being the CAST experiment beneficiary of these developments. In this document we report on the latest upgrades towards further background reductions and better understanding of the detectors' response. The upgrades encompass the readout electronics, a new detector design and the implementation of a more efficient cosmic muon veto system. Background levels below 10-6keV-1cm-2s-1 have been obtained at sea level for the first time, demonstrating the feasibility of the expectations posed by IAXO, the next generation axion helioscope. Some results obtained with a set of measurements conducted in the x-ray beam of the CAST Detector Laboratory will be also presented and discussed.

Aune, S.; Aznar, F.; Calvet, D.; Dafni, T.; Diago, A.; Druillole, F.; Fanourakis, G.; Ferrer-Ribas, E.; Galán, J.; García, J. A.; Gardikiotis, A.; Garza, J. G.; Geralis, T.; Giomataris, I.; Gómez, H.; González-Díaz, D.; Herrera, D. C.; Iguaz, F. J.; Irastorza, I. G.; Jourde, D.; Luzón, G.; Mirallas, H.; Mols, J. P.; Papaevangelou, T.; Rodríguez, A.; Seguí, L.; Tomás, A.; Vafeiadis, T.; Yildiz, S. C.

2013-12-01

18

The Sources of F10.7 Emission  

NASA Astrophysics Data System (ADS)

The solar radio flux at a wavelength of 10.7 cm, F10.7, serves as a proxy for the Sun’s ionizing flux striking the Earth and is a heavily used index for space weather studies. In principal both the coronal sources of ionizing flux and strong coronal magnetic fields contribute to F10.7 via different emission mechanisms. Recently the Expanded Very Large Array (EVLA) has added the capability to make high-spatial-resolution images of the Sun at 10.7 cm. In this work we compare a trial F10.7 image from the EVLA with the radio emission predicted to be present from EUV images of the Sun acquired by the AIA telescope on the Solar Dynamics Observatory at 6 wavelengths covering the coronal temperature range. Photospheric magnetograms are used to identify likely regions of strong coronal magnetic field, and the circular polarization measured by the EVLA is used as a tracer of gyroresonance contributions to F10.7. We discuss the conversion of the EUV data to bremsstrahlung radio fluxes via the construction of differential emission measure images, and analyze the relative contributions of the different sources of F10.7 flux.

Schonfeld, Samuel J.; White, Stephen M.; Henney, Carl John; McAteer, James; Arge, Charles

2014-06-01

19

The Sources of F10.7 Emission  

NASA Astrophysics Data System (ADS)

The solar radio flux at a wavelength of 10.7 cm, F10.7, serves as a proxy for the Sun's ionizing flux striking the Earth and is a heavily used index for space weather studies. In principle both the coronal sources of ionizing flux and strong coronal magnetic fields contribute to F10.7 via different emission mechanisms. Recently the Expanded Very Large Array (EVLA) has added the capability to make high-spatial-resolution images of the Sun at 10.7 cm. In this work we compare a trial F10.7 image from the EVLA with the radio emission predicted to be present from EUV images of the Sun acquired by the AIA telescope on the Solar Dynamics Observatory at 6 wavelengths covering the coronal temperature range. Photospheric magnetograms are used to identify likely regions of strong coronal magnetic field, and the circular polarization measured by the EVLA is used as a tracer of gyroresonance contributions to F10.7. We discuss the conversion of the EUV data to bremsstrahlung radio fluxes via the construction of differential emission measure images, and analyze the relative contributions of the different sources of F10.7 flux.

Schonfeld, S.; White, S. M.; Henney, C. J.; Mcateer, R.; Arge, C. N.

2013-12-01

20

Mg dopant in Cu2ZnSnSe4: An n-type former and a promoter of electrical mobility up to 120 cm2 V-1 s-1  

NASA Astrophysics Data System (ADS)

Mg-doped Cu2ZnSnSe4 (CZTSe) bulk materials with the (Cu2-xMgx)ZnSnSe4 formula at x=0, 0.1, 0.2, 0.3, and 0.4 were prepared at 600 °C for 2 h with soluble sintering aids of Sb2S3 and Te. Defect chemistry was studied by measuring structural and electrical properties of Mg-doped CZTSe as a function of dopant concentration. Except at x=0, all Mg-doped CZTSe pellets showed an n-type behavior. The Mg-doped CZTSe pellets showed an n-type behavior. n-Type Mg-CZTSe pellets at x=0.1 showed the highest electrical conductivity of 24.6 S cm-1 and the net hole mobility of 120 cm2 V-1 s-1, while they were 11.8 S cm-1 and 36.5 cm2 V-1 s-1 for the undoped p-type CZTSe. Mg dopant is a strong promoter of electrical mobility. Mg dopant behaves as a donor defect in CZTSe at a 5% doping content, but is also used as an acceptor at a high content above 5%. Mg doping has further developed CZTSe into a promising semiconductor.

Kuo, Dong-Hau; Wubet, Walelign

2014-07-01

21

Capillary Pressure - Mac OS 10.7  

NSDL National Science Digital Library

Computer program for Mac OS 10.7 to illustrate the vascular control of capillary hydrostatic pressure. Possible simulations include arteriolar vasoconstriction and dilation, venous obstruction, hypotension, reflex vasoconstriction, etc.

2004-10-01

22

Critical role of alkyl chain branching of organic semiconductors in enabling solution-processed N-channel organic thin-film transistors with mobility of up to 3.50 cm² V(-1) s(-1).  

PubMed

Substituted side chains are fundamental units in solution processable organic semiconductors in order to achieve a balance of close intermolecular stacking, high crystallinity, and good compatibility with different wet techniques. Based on four air-stable solution-processed naphthalene diimides fused with 2-(1,3-dithiol-2-ylidene)malononitrile groups (NDI-DTYM2) that bear branched alkyl chains with varied side-chain length and different branching position, we have carried out systematic studies on the relationship between film microstructure and charge transport in their organic thin-film transistors (OTFTs). In particular synchrotron measurements (grazing incidence X-ray diffraction and near-edge X-ray absorption fine structure) are combined with device optimization studies to probe the interplay between molecular structure, molecular packing, and OTFT mobility. It is found that the side-chain length has a moderate influence on thin-film microstructure but leads to only limited changes in OTFT performance. In contrast, the position of branching point results in subtle, yet critical changes in molecular packing and leads to dramatic differences in electron mobility ranging from ~0.001 to >3.0 cm(2) V(-1) s(-1). Incorporating a NDI-DTYM2 core with three-branched N-alkyl substituents of C(11,6) results in a dense in-plane molecular packing with an unit cell area of 127 Å(2), larger domain sizes of up to 1000 × 3000 nm(2), and an electron mobility of up to 3.50 cm(2) V(-1) s(-1), which is an unprecedented value for ambient stable n-channel solution-processed OTFTs reported to date. These results demonstrate that variation of the alkyl chain branching point is a powerful strategy for tuning of molecular packing to enable high charge transport mobilities. PMID:23327415

Zhang, Fengjiao; Hu, Yunbin; Schuettfort, Torben; Di, Chong-an; Gao, Xike; McNeill, Christopher R; Thomsen, Lars; Mannsfeld, Stefan C B; Yuan, Wei; Sirringhaus, Henning; Zhu, Daoben

2013-02-13

23

Recent solar radio astronomy at centimeter wavelengths: the temporal variability of the 10. 7-cm flux  

Microsoft Academic Search

Studies made by means of high-resolution radio telescopes indicate that solar centrimetric emission contains contributions from many different sources and involves more than one radiation mechanism. Two emission components have been identified: bright, compact sources and weaker, diffuse emission which is distributed over the plage and surrounding areas of enhanced magnetic field. There is evidence for the occurrence of weaker

K. F. Tapping

1987-01-01

24

46 CFR 113.10-7 - Connection boxes.  

Code of Federal Regulations, 2013 CFR

...DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING COMMUNICATION AND ALARM SYSTEMS AND EQUIPMENT Fire and Smoke Detecting and Alarm Systems § 113.10-7 Connection boxes. Each connection box must be constructed in...

2013-10-01

25

The 700-1500 cm-1 region of the S1 (widetilde A{}^1B_2) state of toluene studied with resonance-enhanced multiphoton ionization (REMPI), zero-kinetic-energy (ZEKE) spectroscopy, and time-resolved slow-electron velocity-map imaging (tr-SEVI) spectroscopy  

NASA Astrophysics Data System (ADS)

We report (nanosecond) resonance-enhanced multiphoton ionization (REMPI), (nanosecond) zero-kinetic-energy (ZEKE) and (picosecond) time-resolved slow-electron velocity map imaging (tr-SEVI) spectra of fully hydrogenated toluene (Tol-h8) and the deuterated-methyl group isotopologue (?3-Tol-d3). Vibrational assignments are made making use of the activity observed in the ZEKE and tr-SEVI spectra, together with the results from quantum chemical and previous experimental results. Here, we examine the 700-1500 cm-1 region of the REMPI spectrum, extending our previous work on the region ?700 cm-1. We provide assignments for the majority of the S1 and cation bands observed, and in particular we gain insight regarding a number of regions where vibrations are coupled via Fermi resonance. We also gain insight into intramolecular vibrational redistribution in this molecule.

Gardner, Adrian M.; Green, Alistair M.; Tamé-Reyes, Victor M.; Reid, Katharine L.; Davies, Julia A.; Parkes, Victoria H. K.; Wright, Timothy G.

2014-03-01

26

Clarifying CM vs. CM At-Risk.  

ERIC Educational Resources Information Center

Explains the difference between construction manager (CM) and construction manager at-risk and explores management versus delivery aspects of both. Concluding comments address why the a decision on CM vs. CM at-risk is not an either/or process. (GR)

Kenig, Michael

2000-01-01

27

The toluene-Ar complex: S0 and S1 van der Waals modes, changes to methyl rotation, and torsion-van der Waals vibration coupling  

NASA Astrophysics Data System (ADS)

The methyl rotor and van der Waals vibrational levels in the S1 and S0 states of toluene-Ar have been investigated by the technique of two-dimensional laser induced fluorescence (2D-LIF). The S0 van der Waals and methyl rotor levels are reported for the first time, while improved S1 values are presented. The correlations seen in the 2D-LIF images between the S0 and S1 states lead to a reassignment of key features in the S1 <-- S0 excitation spectrum. This reassignment reveals that there are significant changes in the methyl rotor levels in the complex compared with those in bare toluene, particularly at low m. The observed rotor energies are explained by the introduction of a three-fold, V3, term in the torsion potential (this term is zero in toluene) and a reduction in the height of the six-fold, V6, barriers in S0 and S1 from their values in bare toluene. The V3 term is larger in magnitude than the V6 term in both S0 and S1. The constants determined are |V3(S1)| = 33.4 +/- 1.0 cm-1, |V3(S0)| = 20.0 +/- 1.0 cm-1, V6(S1) = -10.7 +/- 1.0 cm-1, and V6(S0) = -1.7 +/- 1.0 cm-1. The methyl rotor is also found to couple with van der Waals vibration; specifically, the m'' = 2 rotor state couples with the combination level involving one quantum of the long axis bend and m'' = 1. The coupling constant is determined to be 1.9 cm-1, which is small compared with the values typically reported for torsion-vibration coupling involving ring modes.

Gascooke, Jason R.; Lawrance, Warren D.

2013-02-01

28

The study of time series of monthly averaged values of F10.7 from 1950 to 2010  

NASA Astrophysics Data System (ADS)

Prior to 1947, the activity of the Sun was assessed by the relative numbers of sunspots (W). The 10.7 cm radio emission (frequency of 2.8 GHz) for observations of the variability of radiation of chromosphere and the lower corona (F10.7) became used from 1947. For the F10,7 are available more detailed observational archive data, so this activity index more often than the other indices is used in the prediction and monitoring of the solar activity. We have made the analysis of time series of F10.7 with the use of different mother wavelets: Daubechies 10, Symlet 8, Meyer, Gauss 8 and Morlet. Wavelet spectrum allows us not only to identify cycles, but analyze their change in time. Each wavelet has its own characteristic features, so sometimes with the help of different wavelets it can be better identify and highlight the different properties of the analyzed signal. We intended to choose the mother wavelet, which is more fully gives information about the analyzed index F10.7. We have received, that all these wavelets show similar values to the maximums of the cyclic activity. However, we can see the difference when using different wavelets. There are also a number of periods, which, perhaps, are the harmonics of main period. The mean value of 11-year cycle is about 10.2 years. All the above examples show that the best results we get when using wavelets Morlet, Gauss (real-valued) and multiparameter family of wavelets Morlet and Gauss (complex-valued).

Bruevich, E. A.; Bruevich, V. V.; Yakunina, G. V.

2014-03-01

29

S = -1 Hypernuclear Structure  

NASA Astrophysics Data System (ADS)

The structure of light hypernuclei with strangeness S = -1 is investigated with the three- and four-body cluster model and the Gaussian Expansion method (GEM). Interesting phenomena such as shrinkage effect of the core nucleus and the halo and skin structure due to the glue-like role of Lambda particle are demonstrated from the study of structure of (6_{Lambda}) He, (7_{Lambda}) Li and (13}_{Lambda) C. Precise three- and four-body cluster calculation of (7_{Lambda}) He, (7_{Lambda}) Li, (7_{Lambda}) Be, (9_{Lambda}) Be and (13}_{Lambda) C provide us with information about Lambda N interaction such as spin-spin, spin-orbit, charge symmetry breaking term, etc., by comparing with the recent experimental data. Precise four-body calculation taking NNNLambda and NNNSigma for (4_{Lambda}) H and (4_{Lambda}) He are performed and the role of Lambda-Sigma conversion and the size of the virtual Sigma component in (4_{Lambda}) H and (4_{Lambda}) He are discussed.

Hiyama, E.; Kamimura, M.; Yamamoto, Y.; Motoba, T.; Rijken, T. A.

30

Curvature of super diff(S1)\\/S1  

Microsoft Academic Search

Motivated by the work of Bowick and Rajeev, we calculate the curvature of the infinite-dimensional flag manifolds Diff(S1)\\/S1 and Super Diff(S1)\\/S1 using standard finite-dimensional coset space techniques. We regularize the infinity by zeta-function regularization and recover the conformal and superconformal anomalies respectively for a specific choice of the torsion.

P. Oh; P. Ramond

1987-01-01

31

Validating the solar EUV proxy, E10.7  

NASA Astrophysics Data System (ADS)

A demonstration of the improvement in thermospheric densities using the daily E10.7 proxy compared to F10.7 is shown. The daily altitude decay for the Solar Mesosphere Explorer (SME) satellite from April 1, 1982 through August 9, 1983, using both proxies and the actual altitude data, are compared. The F10.7 case finished 2 km lower than each of the E10.7 and actual altitude cases which were nearly identical. During active solar conditions, daily F10.7 can overestimate the EUV energy input into the atmosphere by up to 60% and also underestimate it by as much as 50%. Progress is shown towards validating E10.7 as a more accurate proxy compared to F10.7 for use in atmospheric density calculations that are applicable to satellite drag problems. In support of the validation of the E10.7 proxy, an operational prototype hardware/software platform for visualizing of the near-Earth space environment was created. This platform uses a data-driven, data visualization environment. Platform development continues so as to accommodate not only historical data but also nowcast and forecast data streams. Upgrades to the SOLAR2000 Research Grade model are continuing in order to improve the correlation coefficients from multiple linear regressions in several wavelength regions. E10.7 is used in applications that incorporate F10.7, including empirical thermospheric models, ionospheric models, and general representations of solar activity ranging from climate research to engineering applications.

Tobiska, W. Kent

2001-12-01

32

3D Kinematic Simulation for PA10-7C Robot Arm Based on VRML  

Microsoft Academic Search

In this paper, a graphical, flexible, interactive, and systematic 3D simulation helps facilitate analyzing and previewing kinematics of PA10-7C robot arm in terms of forward kinematics, inverse kinematics, and the Denavit-Hartenberg convention. Modeling and control are of critical importance when the robot arm is used for practical applications. In the paper, the D-H model of PA10-7C robot arm is given

Weimin Shen; Jason Gu; Yide Ma

2007-01-01

33

The Global S$_1$ Ocean Tide  

NASA Technical Reports Server (NTRS)

The small S$_1$ ocean tide is caused primarily by diurnal atmospheric pressure loading. Its excitation is therefore unlike any other diurnal tide. The global character of $S-1$ is here determined by numerical modeling and by analysis of Topex/Poseidon satellite altimeter data. The two approaches yield reasonably consistent results, and large ( $ greater than $l\\cm) amplitudes in several regions are further confirmed by comparison with coastal tide gauges. Notwithstanding their excitation differences, S$-1$ and other diurnal tides are found to share several common features, such as relatively large amplitudes in the Arabian Sea, the Sea of Okhotsk, and the Gulf of Alaska. The most noticeable difference is the lack of an S$-1$ Antarctic Kelvin wave. These similarities and differences can be explained in terms of the coherences between near-diurnal oceanic normal modes and the underlying tidal forcings. While gravitational diurnal tidal forces excite primarily a 28-hour Antarctic-Pacific mode, the S$_1$ air tide excites several other near-diurnal modes, none of which has large amplitudes near Antarctica.

Ray, Richard D.; Egbert, G. D.

2003-01-01

34

Ubiquitous CM and DM  

NASA Technical Reports Server (NTRS)

Ubiquitous is a real word. I thank a former Total Quality Coach for my first exposure some years ago to its existence. My version of Webster's dictionary defines ubiquitous as "present, or seeming to be present, everywhere at the same time; omnipresent." While I believe that God is omnipresent, I have come to discover that CM and DM are present everywhere. Oh, yes; I define CM as Configuration Management and DM as either Data or Document Management. Ten years ago, I had my first introduction to the CM world. I had an opportunity to do CM for the Space Station effort at the NASA Lewis Research Center. I learned that CM was a discipline that had four areas of focus: identification, control, status accounting, and verification. I was certified as a CMIl graduate and was indoctrinated about clear, concise, and valid. Off I went into a world of entirely new experiences. I was exposed to change requests and change boards first hand. I also learned about implementation of changes, and then of technical and CM requirements.

Crowley, Sandra L.

2000-01-01

35

The superstring, diff S1\\/S1, and holomorphic geometry  

Microsoft Academic Search

We incorporate superstrings into the non-perturbative formulation of string field theories based on Kähler geometry recently proposed by Bowick and Rajeev. The string field is conjectured to be the Kähler potential of loop space, its equation of motion given by the vanishing of the curvature of a product bundle constructed over a graded Diff S1\\/S1, as required for reparametrization invariance

Diego Harari; Deog Ki Hong; Pierre Ramond; V. G. J. Rodgers

1987-01-01

36

21cm Intensity Mapping  

NASA Astrophysics Data System (ADS)

The redshifted 21-cm emission from neutral hydrogen has emerged as a powerful probe for large-scale structure; a significant fraction of the observable universe can be mapped in the intensity mapping regime out to high redshifts. At redshifts around unity, the 21-cm emission traces the matter distribution and can be used to measure the Baryon Acoustic Oscillation (BAO) signature and constrain dark energy properties. I will describe our on-going observing program at the Green Bank Telescope (GBT), aiming to measure the 21cm power spectrum at z=0.8. A 800-MHz multi-beam focal-plane array for the GBT is currently under construction in order to facilitate a large-scale survey for BAO and the redshift-space distortion measurements for cosmological constraints.

Chang, Tzu-Ching; GBT-HIM Team

2014-04-01

37

Halogens in CM Chondrites  

NASA Astrophysics Data System (ADS)

We set up an extraction line of halogens (fluorine, chlorine) by pyrohydrolysis with 50 mg of rock. We analyzed 7 CM2 chondrites found in Antarctica and found that the Cl content of meteorites with an intact fusion crust is higher than those without.

Menard, J. M.; Caron, B.; Jambon, A.; Michel, A.; Villemant, B.

2013-09-01

38

An Absolute Measurement of the Cosmic Microwave Background Radiation Temperature at 10.7 GHz  

Microsoft Academic Search

A balloon-borne experiment has measured the absolute temperature of the cosmic microwave background radiation (CMBR) at 10.7 GHz to be TCMBR = 2.730 +\\/- 0.014 K. The error is the quadratic sum of several systematic errors, with a statistical error of less than 0.1 mK. The instrument is made up of a cooled corrugated horn antenna coupled to a total

S. T. Staggs; N. C. Jarosik; S. S. Meyer; D. T. Wilkinson

1996-01-01

39

An Absolute Measurement of the Cosmic Microwave Background Radiation Temperature at 10.7 GHz  

Microsoft Academic Search

A balloon-borne experiment has measured the absolute temperature of the\\u000acosmic microwave background radiation (CMBR) at 10.7 GHz to be Tcmbr = 2.730\\u000a+- .014 K. The error is the quadratic sum of several systematic errors, with\\u000astatistical error of less than 0.1 mK. The instrument comprises a cooled\\u000acorrugated horn antenna coupled to a total-power radiometer. A cryogenic\\u000amechanical

S. T. Staggs; N. C. Jarosik; S. S. Meyer; D. T. Wilkinson

1996-01-01

40

Magnetohydrodynamics of the 10.7 hr Magnetic Periodicities in Saturn's Magnetosphere  

NASA Astrophysics Data System (ADS)

The observed features of the global 10.7 hour period magnetic signals of the Saturn system are analysed using the reasonable guiding hypothesis that the phenomena are magnetohydrodynamic in origin. In uniform plasma shear and compressional waves are separated. Inhomogeneity causes the coupling of the shear and compressional plasma motion but because of the anisotropy of the magnetic stress, it is still important to analyse compressional and shear effects independently and then allow for coupling. Three regimes can be defined where behavior of fields is very different. These are the flux tubes that are permanently closed and those that are permanently open (polar cap) and the open-closed boundary regime between these regions, where field lines open and sporadically (and periodically) release trapped material into interplanetary space. A central question to deriving a global picture is the manner in which the 10.7 hour signals connect across the interfaces between regimes. Globally the model we deduce predicts fields and plasma behavior largely indistinguishable from the recent global computations of Jia et al.[1] However there are limitations to the detail that any computation can reproduce. Moreover, we show that the source vortices introduced in the computations arise as a natural feature of the Saturn plasma environment.

Southwood, D. J.

2013-09-01

41

7S(1/2) ? 9S(1/2) two-photon spectroscopy of trapped francium.  

PubMed

We report on the spectroscopic measurement of the (210)Fr 9S(1/2) energy obtained by two-photon excitation of atoms confined and cooled in a magneto-optic trap. The resonant intermediate level 7P(3/2) is the upper state of the trapping transition. We have measured the energy difference between the 9S(1/2) state and the 7S(1/2) ground state to be 25 671.021 +/- 0.006 cm(-1). PMID:19881852

Simsarian, J E; Shi, W; Orozco, L A; Sprouse, G D; Zhao, W Z

1996-12-01

42

Lifetimes of 5d{sup 10}7p levels in Hg II  

SciTech Connect

Measurement of lifetimes of low-lying levels in Hg II have been made using thin foil excitation of a fast ion beam using the University of Toledo 330 kV heavy ion accelerator. The lifetimes were extracted both by exponential curve fitting of the individual decay curves and by joint analysis of the cascade-correlated decay curves using the ANDC method. Some of these levels possess interesting subtleties that can greatly limit the reliability of ab initio calculations for their specification, and make experimental determination especially important. For example, for the 5d{sup 10}7p lifetimes exhibit anomalous lifetime ratios for the J=1/2 and J=3/2 fine structure levels resulting from the combined influence of a near-lying Cooper minimum and CI-induced decay to the 5d{sup 9}6s{sup 2} levels.

Maniak, S.T.; Curtis, L.J.; Irving, R.E. [Univ. of Toledo, OH (United States)] [and others

1993-05-01

43

43 CFR 10.7 - Disposition of unclaimed human remains, funerary objects, sacred objects, or objects of cultural...  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Disposition of unclaimed human remains, funerary objects, sacred objects...PROTECTION AND REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects...Lands § 10.7 Disposition of unclaimed human remains, funerary objects, sacred...

2013-10-01

44

CM-458/U Signal Comparator  

SciTech Connect

The development history, the physical and functional characteristics, and the production activity of the CM-458/U Signal Comparator is described. The CM-458/U Signal Comparator is a test device used to verify proper delivery by the aircraft control equipment of the unique signal used in the prearming of modern nuclear weapons. CM-458/U monitors voltage levels, pulse widths and signal sequence to verify correctness.

Merritt, W. G.; Kestly, J. D.

1980-06-01

45

Resistance to He2+ induced irradiation damage in metallic glass Zr64Cu17.8Ni10.7Al7.5  

NASA Astrophysics Data System (ADS)

This paper used He2+ ion-irradiated metallic glass Zr64Cu17.8Ni10.7Al7.5 and metallic W with an energy of 500 keV at fluences of 2 × 1017, 5 × 1017, 1 × 1018 and 2 × 1018 ions/cm2. Zr-based metallic glass remained mainly amorphous at different fluences. At the irradiation fluence of 2 × 1018 ions/cm2, there was a channel-like damage layer appeared within the range of the surface ions. Cracking and peeling along the grain boundary occurred on the surface of metallic W at the fluence of 1 × 1018 ions/cm2; or even multi-layer peeling occurred at the fluence of 2 × 1018 ions/cm2. TEM analysis revealed that there were a lot of helium bubbles at the end of the range of helium ion. The connection and coalescence growth process of a helium bubble was observed. The surface rms roughness ?rms of Zr-based metallic glass increased first and then decreased with the increase in fluence. The resistance to He2+ irradiation in Zr-based metallic glass was superior to the one in metallic tungsten.

Wang, Bin; Mei, Xianxiu; Zhang, Hongran; Hou, Wenjing; Wang, Younian; Wang, Zhiguang; Dong, Chuang

2014-01-01

46

Formation of ultracold LiRb molecules by photoassociation near the Li(2s?2S1/2) + Rb(5p?2P1/2) asymptote  

NASA Astrophysics Data System (ADS)

We report the production of ultracold 7Li85Rb molecules by photoassociation (PA) below the Li (2s?2S1/2) + Rb(5p?2P1/2) asymptote. We perform PA spectroscopy in a dual-species 7Li-85Rb magneto-optical trap (MOT) and detect the PA resonances using trap loss spectroscopy. We observe several strong PA resonances corresponding to the last few bound states, assign the lines and derive the long-range C6 dispersion coefficients for the Li (2s?2S1/2) + Rb(5p?2P1/2) asymptote. We also report an excited-state molecule formation rate (P_{\\textit{LiRb}}) of {\\sim}10^{7}\\ \\text{s}^{-1} and a PA rate coefficient (K_{PA}) of {\\sim}4\\times10^{-11}\\ \\text{cm}^3/\\text{s} , which are both among the highest observed for heteronuclear bi-alkali molecules. These suggest that PA is a promising route for the creation of ultracold ground-state LiRb molecules.

Dutta, Sourav; Elliott, Daniel S.; Chen, Yong P.

2013-12-01

47

The New Isotopes 233Cm and 234Cm  

NASA Astrophysics Data System (ADS)

The new isotopes 233Cm and 234Cm were produced using the reaction 198Pt(40Ar,xn)238-xCm(x=4,5). Five different bombarding energies of Elab=184, 192, 196, 200 and 208 MeV respectively, were used to measure the excitation function for the 4n evaporation channel. A maximum production cross section of ?4n ?1 nb was measured. The ?-decay branch of 234Cm was identified by ?-? -correlations to known daughter products 230Pu, 226U, 222Th, 218Ra and 214Rn. The measured ? decay energy is E? = (7239 ± 10) keV, the half-life was determined to be T1/2 = (51 ± 12) s. Also 26 fission events, tentatively assigned to a fission branch of 234Cm, were observed. The technique of ?-? - correlations allowed to determine the half-life of 230Pu to be T1/2 = (102 ± 10) s. The EC branch of 230Pu was estimated to be lower than 27 %. The identification of 233Cm was also based on the ?-? - correlations to its known daughter products 229Pu, 225U, 221Th, 217Ra and 213Rn. Five such decay chains were observed at the bombarding energy of 208 MeV. In addition 7 decay chains starting with the same ? energy but followed by decays of 229Np, 225Pa, 221Ac, 217Fr and 213At were detected. The ? energy of E? = (7340 ± 10) keV was determined for 233Cm, the half-life could not be measured. The half-life of 229Pu was measured to be T1/2 = (90 ± 10) s.

Cagarda, P.; Antalic, S.; Šáro, Š.; Hofmann, S.; Heßberger, F. P.; Ackermann, D.; Kindler, B.; Lommel, B.; Kojouharova, J.; Mann, R.; Schött, H. J.; Yeremin, A. V.; Popeko, A. G.; Uusitalo, J.

2002-12-01

48

CYP2S1: A short review  

Microsoft Academic Search

A new member of the cytochrome P450 superfamily, CYP2S1, has recently been identified in human and mouse. In this paper, we review the data currently available for CYP2S1. The human CYP2S1 gene is located in chromosome 19q13.2 within a cluster including CYP2 family members CYP2A6, CYP2A13, CYP2B6, and CYP2F1. These genes also show the highest homology to the human CYP2S1.

Sirkku T.. Saarikoski; Steven P. Rivera; Oliver Hankinson; Kirsti Husgafvel-Pursiainen

2005-01-01

49

CYP2S1: A short review  

SciTech Connect

A new member of the cytochrome P450 superfamily, CYP2S1, has recently been identified in human and mouse. In this paper, we review the data currently available for CYP2S1. The human CYP2S1 gene is located in chromosome 19q13.2 within a cluster including CYP2 family members CYP2A6, CYP2A13, CYP2B6, and CYP2F1. These genes also show the highest homology to the human CYP2S1. The gene has recently been found to harbor genetic polymorphism. CYP2S1 is inducible by dioxin, the induction being mediated by the Aryl Hydrocarbon Receptor (AHR) and Aryl Hydrocarbon Nuclear Translocator (ARNT) in a manner typical for CYP1 family members. In line with this, CYP2S1 has been shown to be inducible by coal tar, an abundant source of PAHs, and it was recently reported to metabolize naphthalene. This points to the involvement of CYP2S1 in the metabolism of toxic and carcinogenic compounds, similar to other dioxin-inducible CYPs. CYP2S1 is expressed in epithelial cells of a wide variety of extrahepatic tissues. The highest expression levels have been observed in the epithelial tissues frequently exposed to xenobiotics, e.g., the respiratory, gastrointestinal, and urinary tracts, and in the skin. The observed ubiquitous tissue distribution, as well as the expression of CYP2S1 throughout embryogenesis suggest that CYP2S1 is likely to metabolize important endogenous substrates; thus far, retinoic acid has been identified. In conclusion, CYP2S1 exhibits many features of interest for human health and thus warrants further investigation.

Saarikoski, Sirkku T. [Department of Industrial Hygiene and Toxicology, Finnish Institute of Occupational Health, FI-00250 (Finland) and Department of Mental Health and Alcohol Research, National Public Health Institute, FI-00250 (Finland)]. E-mail: sirkku.saarikoski@ktl.fi; Rivera, Steven P. [Department of Pathology and Laboratory Medicine, Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095 (United States); Hankinson, Oliver [Department of Pathology and Laboratory Medicine, Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095 (United States); Husgafvel-Pursiainen, Kirsti [Department of Industrial Hygiene and Toxicology, Finnish Institute of Occupational Health, FI-00250 (Finland)

2005-09-01

50

Serpentine Nanotubes in CM Chondrites  

NASA Technical Reports Server (NTRS)

The CM chondrites are primitive meteorites that formed during the early solar system. Although they retain much of their original physical character, their matrices and fine-grained rims (FGRs) sustained aqueous alteration early in their histories [1- 3]. Serpentine-group minerals are abundant products of such alteration, and information regarding their structures, compositions, and spatial relationships is important for determining the reactions that produced them and the conditions under which they formed. Our recent work on FGRs and matrices of the CM chondrites has revealed new information on the structures and compositions of serpentine-group minerals [4,5] and has provided insights into the evolution of these primitive meteorites. Here we report on serpentine nanotubes from the Mighei and Murchison CM chondrites [6].

Zega, Thomas J.; Garvie, Laurence A. J.; Dodony, Istvan; Buseck, Peter R.

2004-01-01

51

344 cm x 86 cm low mass vacuum window  

SciTech Connect

The LBL Heavy Ion Spectrometer System (HISS) superconducting magnet contains a 1 m x 3.45 m x 2 m vacuum tank in its gap. A full aperture thin window was needed to minimize background as the products of nuclear collisions move from upstream targets to downstream detectors. Six windows were built and tested in the development process. The final window's unsupported area is 3m/sup 2/ with a 25 cm inward deflection. The design consists of a .11 mm Nylon/aluminum/polypropylene laminate as a gas seal and .55 mm woven aramid fiber for strength. Total mass is 80 milligrams per cm/sup 2/. Development depended heavily on past experience and testing. Safety considerations are discussed.

Reimers, R.M.; Porter, J.; Meneghetti, J.; Wilde, S.; Miller, R.

1983-08-01

52

Magnetic study of CM chondrites  

NASA Astrophysics Data System (ADS)

The study of the paleomagnetism of carbonaceous chondrites can lead to an estimate of the magnetic fields present in the early solar system. CM chondrites contain abundant magnetite formed during aqueous alteration on their parent body, and have not been heated after that, making them interesting targets for paleomagnetism. We performed a detailed and comparative magnetic study (paleomagnetism and rock magnetism) of three CM chondrites: Paris, Cold Bokkeveled and Murchison. These three meteorites cover a wide range of aqueous alteration, with increasing alteration from Paris [1] to Murchison to Cold Bokkeveld [2]. Paris is a unique CM chondrite significantly less aqueously altered than other CM chondrites. Our magnetic data show that in contrast with other CM, Paris meteorite contains abundant FeNi metal (of nebular origin) together with magnetite and pyrrhotite (of asteroidal origin). Paleomagnetic results of Paris show that unfortunately the meteorite has been exposed to a strong artificial magnetic field (magnet), precluding the study of the natural magnetization (of possible nebular origin) carried by FeNi. However, a high-coercivity magnetization carried by pyrrhotite is still preserved in the meteorite. It is homogeneous in direction and intensity at the scale of the meteorite. We interpret this high-coercivity magnetization as a pre-terrestrial chemical remanent magnetization acquired on the parent body in a field of a few µT. Our preliminary results on Murchison also evidenced an stable and homogeneous magnetization in the meteorite. Therefore a long-lasting stable magnetizing field seems necessary to account for the paleomagnetism of both meteorites. Because crystallization of pyrrhotite and magnetite occurred several Myr after the formation of the parent body [3] (i.e. after possible existence of strong solar and nebular magnetic field), the magnetizing field was most probably created on the parent body. In view of its intensity, the most plausible origin for the magnetizing field is an internally generated dynamo field. This would imply that the parent body of CM chondrites was partially differentiated with a convecting metallic core. Such process has recently been proposed for the parent body of CV chondrites [4, 5]. [1] Zanda et al., 2010. Meteoritics Planetary Sci., 45, 222-222. [2] Rubin et al., 2007. Geo. et Cosmo. Acta, 71, 2361-2382 [3] Krot et al., 2005. UCRL-BOOK-217207 [4] Carporzen et al., 2011. Proc. National Acad. Sci., 108, 6386-6389. [5] Elkins-Tanton et al., 2011. Earth Planet . Sci. Lett., 305, 1-10.

Cournède, C.; Gattacceca, J.; Zanda, B.; Rochette, P.

2012-04-01

53

S1×S2 Gowdy supersymmetric constraint  

NASA Astrophysics Data System (ADS)

We obtain the supersymmetric constraint for S1×S2 Gowdy spacetime in the N=1 supergravity formalism of quantum cosmology in four dimensions. The physical states of the model for both polarized and unpolarized cases are presented.

Maceda, Marco; Macías, Alfredo

2011-02-01

54

AMR on the CM-2  

NASA Technical Reports Server (NTRS)

We describe the development of a structured adaptive mesh algorithm (AMR) for the Connection Machine-2 (CM-2). We develop a data layout scheme that preserves locality even for communication between fine and coarse grids. On 8K of a 32K machine we achieve performance slightly less than 1 CPU of the Cray Y-MP. We apply our algorithm to an inviscid compressible flow problem.

Berger, Marsha J.; Saltzman, Jeff S.

1992-01-01

55

Observations of the supernova remnant 3C391 at 1.4 and 10.7 GHz  

Microsoft Academic Search

The supernova remnant 3C 391 has been mapped at 1.4 GHz with the Fleurs Synthesis Telescope (resolution 54 x 66 arcsec) and at 10.7 GHz with the 100-m Effelsberg telescope (resolution 77 arcsec). An incomplete shell structure is observed. There is no evidence for the small-diameter H II regions hypothesized by Bridle and Kesteven (1971) and Chaisson (1974); the thermal

W. M. Goss; P. A. Shaver; D. J. Skellern; A. Watkinson

1979-01-01

56

Efficacy of S-1 in colorectal cancer.  

PubMed

Introduction: S-1 is an oral fluoropyrimidine that consists of tegafur, 5-chloro-2, 4-dihydroxypyridine and potassium oxonate. It has been developed as a prodrug of 5-fluorouracil with the goal of improving therapeutic efficacy and tolerability. Areas covered: This review aims to provide an evidence-based update of clinical trials that have investigated the clinical efficacy, adverse-event profile, dosage and administration of S-1, given alone or in combination with conventional chemotherapeutics and new target-oriented drugs, in the management of colorectal cancer (CRC). Additionally, differences in the tolerability and pharmacokinetics of S-1 between Caucasians and Asians have been described. Finally, the therapeutic efficacy of S-1 regarding metastatic CRC or postoperative CRC has been discussed. Available data have stimulated further research, including Phase III trials for the treatment of advanced CRC. Expert opinion: Treatment using S-1 combined with oxaliplatin (± bevacizumab) and irinotecan has achieved promising results in terms of feasibility, safety and effectiveness. Furthermore, S-1 is an acceptable treatment as adjuvant chemotherapy for colon cancer. PMID:25032886

Miyamoto, Yuji; Sakamoto, Yasuo; Yoshida, Naoya; Baba, Hideo

2014-08-01

57

21 cm angular spectrum of cosmic string loops  

NASA Astrophysics Data System (ADS)

The 21 cm signatures induced by moving cosmic string loops are investigated. Moving cosmic string loops seed filamentary nonlinear objects. We analytically evaluate the differential 21 cm brightness temperature from these objects. We show that the brightness temperature reaches 200 mK for a loop whose tension is about the current upper limit, G?˜10-7. We also calculate the angular power spectrum, assuming scaling in loop distribution. We find that the angular power spectrum for G?>10-8 at z=30 or G?>10-10 at z=20 can dominate the spectrum of the primordial density fluctuations. Finally we show that a future SKA-like observation has the potential to detect the power spectrum due to loops with G?=10-8 at z=20.

Tashiro, Hiroyuki

2013-06-01

58

21 cm Tomography with Foregrounds  

NASA Astrophysics Data System (ADS)

Twenty-one centimeter tomography is emerging as a powerful tool to explore the reionization epoch and cosmological parameters, but it will only be as good as our ability to accurately model and remove astrophysical foreground contamination. Previous treatments of this problem have focused on the angular structure of the signal and foregrounds and what can be achieved with limited spectral resolution (channel widths in the 1 MHz range). In this paper we introduce and evaluate a ``blind'' method to extract the multifrequency 21 cm signal by taking advantage of the smooth frequency structure of the Galactic and extragalactic foregrounds. We find that 21 cm tomography is typically limited by foregrounds on scales of k<<1 h Mpc-1 and is limited by noise on scales of k>>1 h Mpc-1, provided that the experimental channel width can be made substantially smaller than 0.1 MHz. Our results show that this approach is quite promising even for scenarios with rather extreme contamination from point sources and diffuse Galactic emission, which bodes well for upcoming experiments such as LOFAR, MWA, PAST, and SKA.

Wang, Xiaomin; Tegmark, Max; Santos, Mário G.; Knox, Lloyd

2006-10-01

59

Measurement of the spin-exchange and chemical ionization rate constants in collisions of polarized metastable 23 S 1 helium atoms with 32 S 1/2 sodium atoms  

NASA Astrophysics Data System (ADS)

Experimental data on the spin-exchange rate constants for the He(23 S 1)-Na(32 S 1/2) system are reported for the first time. Measurements show that the spin-exchange rate constant is C se = (23 ± 11) × 10-10 cm3 s-1 and the chemical ionization rate constant is C si = (29 ± 14) × 10-10 cm3 s-1 at a temperature of 420 K. The results are compared with the data calculated from the rate constants.

Dmitriev, S. P.; Dovator, N. A.; Kartoshkin, V. A.

2009-10-01

60

The effect of primordial black holes on 21-cm fluctuations  

NASA Astrophysics Data System (ADS)

The 21-cm signal produced by non-evaporating primordial black holes (PBHs) is investigated. X-ray photons emitted by accretion of matter onto a PBH ionize and heat the intergalactic medium (IGM) gas near the PBH. Using a simple analytic model, we show that this X-ray heating can produce an observable differential 21-cm brightness temperature. The region of the observable 21-cm brightness temperature can extend to 1-10 Mpc comoving distance from a PBH, depending on the PBH mass. The angular power spectrum of 21-cm fluctuations resulting from PBHs is also calculated. The peak position of the angular spectrum depends on the PBH mass, while the amplitude is independent of mass. On comparing this power spectrum with the angular power spectrum caused by primordial density fluctuations, it is found that the two spectra are comparable if the density parameter of PBHs is ?PBH = 10-11(M/103 M?)-0.2 at z = 30 and if ?PBH = 10-12(M/103 M?)-0.2 at z = 20 for a PBH mass from 10 M? to 108 M?. Finally, we find that the Square Kilometre Array can detect the signal caused by PBHs up to ?PBH = 10-5(M/103 M?)-0.2 at z = 30 and up to ?PBH = 10-7(M/103 M?)-0.2 at z = 20 for PBHs with mass in the range from 102 M? to 108 M?.

Tashiro, Hiroyuki; Sugiyama, Naoshi

2013-11-01

61

A S = 1 underscreened Kondo lattice model  

Microsoft Academic Search

The underscreened Kondo lattice model presented here includes both an intra-site Kondo exchange interaction JK between the conduction band and localized 5f electrons described by S=1 spins, and an inter-site exchange f–f interaction JH. We write both localized and itinerant spins in a Fermionic representation, and then use a mean-field approximation. We obtain a coexistence of Kondo effect and magnetism

N. B. Perkins; M. D. Núñez-Regueiro; J. R. Iglesias; B. Coqblin

2006-01-01

62

A S=1 underscreened Kondo lattice model  

Microsoft Academic Search

The underscreened Kondo lattice model presented here includes both an intra-site Kondo exchange interaction J between the conduction band and localized 5f electrons described by S=1 spins, and an inter-site exchange f f interaction J. We write both localized and itinerant spins in a Fermionic representation, and then use a mean-field approximation. We obtain a coexistence of Kondo effect and

N. B. Perkins; M. D. Núñez-Regueiro; J. R. Iglesias; B. Coqblin

2006-01-01

63

Solubility of methane in heavy normal paraffins at temperatures from 323 to 423 K and pressures to 10. 7 MPa  

SciTech Connect

Solubility data are presented for methane in four heavy normal paraffins at temperatures from 323 to 423 K and pressures up to 10.7 MPa. The paraffins studied are eicosane (n-C[sub 20]), octacosane(n-C[sub 28]), hexatriacontane (n-C[sub 36]), and tetratetracontane (n-C[sub 44]). The data obtained for the solubility of methane in n-C[sub 20], n-C[sub 28], and n-C[sub 36] are in good agreement with the earlier measurements of Chao and co-workers. The new data can be described with RMS errors of about 0.001 in mole fraction by the Soave-Redlich-Kwong (SRK) or Peng-Robinson (PR) equation of state when two interaction parameters per isotherm are used. Henry's constants and partial molar volumes at infinite dilution for methane have also been evaluated from the data.

Darwish, N.A.; Fathikalajahi, J.; Gasem, K.A.M.; Robinson, R.L. Jr. (Oklahoma State Univ., Stillwater, OK (United States). School of Chemical Engineering)

1993-01-01

64

Sphingosine-1-phosphate (S1P) displays sustained S1P1 receptor agonism and signaling through S1P lyase-dependent receptor recycling.  

PubMed

The sphingosine-1-phosphate (S1P) type 1 receptor (S1P1R) is a novel therapeutic target in lymphocyte-mediated autoimmune diseases. S1P1 receptor desensitization caused by synthetic S1P1 receptor agonists prevents T-lymphocyte egress from secondary lymphoid organs into the circulation. The selective S1P1 receptor agonist ponesimod, which is in development for the treatment of autoimmune diseases, efficiently reduces peripheral lymphocyte counts and displays efficacy in animal models of autoimmune disease. Using ponesimod and the natural ligand S1P, we investigated the molecular mechanisms leading to different signaling, desensitization and trafficking behavior of S1P1 receptors. In recombinant S1P1 receptor-expressing cells, ponesimod and S1P triggered G?i protein-mediated signaling and ?-arrestin recruitment with comparable potency and efficiency, but only ponesimod efficiently induced intracellular receptor accumulation. In human umbilical vein endothelial cells (HUVEC), ponesimod and S1P triggered translocation of the endogenous S1P1 receptor to the Golgi compartment. However, only ponesimod treatment caused efficient surface receptor depletion, receptor accumulation in the Golgi and degradation. Impedance measurements in HUVEC showed that ponesimod induced only short-lived G?i protein-mediated signaling followed by resistance to further stimulation, whereas S1P induced sustained G?i protein-mediated signaling without desensitization. Inhibition of S1P lyase activity in HUVEC rendered S1P an efficient S1P1 receptor internalizing compound and abrogated S1P-mediated sustained signaling. This suggests that S1P lyase - by facilitating S1P1 receptor recycling - is essential for S1P-mediated sustained signaling, and that synthetic agonists are functional antagonists because they are not S1P lyase substrates. PMID:24704119

Gatfield, John; Monnier, Lucile; Studer, Rolf; Bolli, Martin H; Steiner, Beat; Nayler, Oliver

2014-07-01

65

Will Comet ISON (C/2012 S1) Survive Perihelion?  

NASA Astrophysics Data System (ADS)

On 2013 November 28 Comet ISON (C/2012 S1) will pass by the Sun with a perihelion distance of 2.7 solar radii. Understanding the possible outcomes for the comet's response to such a close passage by the Sun is important for planning observational campaigns and for inferring ISON's physical properties. We present new numerical simulations and interpret them in context with the historical track record of comet disruptions and of sungrazing comet behavior. Historical data suggest that sizes below ~200 m are susceptible to destruction by sublimation driven mass loss, while we find that for ISON's perihelion distance, densities lower than 0.1 g cm-3 are required to tidally disrupt a retrograde or non-spinning body. Such low densities are substantially below the range of the best-determined comet nucleus densities, though dynamically new comets such as ISON have few measurements of physical properties. Disruption may occur for prograde rotation at densities up to 0.7 g cm-3, with the chances of disruption increasing for lower density, faster prograde rotation, and increasing elongation of the nucleus. Given current constraints on ISON's nucleus properties and the typically determined values for these properties among all comets, we find tidal disruption to be unlikely unless other factors (e.g., spin-up via torquing) affect ISON substantially. Whether or not disruption occurs, the largest remnant must be big enough to survive subsequent mass loss due to sublimation in order for ISON to remain a viable comet well after perihelion.

Knight, Matthew M.; Walsh, Kevin J.

2013-10-01

66

Comet C/2012 S1 (Ison)  

NASA Astrophysics Data System (ADS)

S. Nakano, Sumoto, Japan, has also reported the following unsuccessful CCD searches for the comet after perihelion, with limiting magnitudes: Dec. 8.85 UT, [16.6 (K. Kadota, Ageo, Japan, 0.16-m f/3.3 hyperbolic astrograph); 8.88, [15 (Katsumi Yoshimoto, Yamaguchi, Japan, 16-cm reflector); 10.85, [17.2 (Kadota); 12.86, [17 (Y. Ikari, Moriyama, Shiga-ken, Japan, 0.26-m reflector); 14.86, [15.5 (Yoshimoto, Nikon digital camera + 180-mm f/2.8 lens).

Nakano, S.; Kadota, K.; Ikari, Y.

2013-12-01

67

The contribution of AMSR-E 18.7 and 10.7 GHz measurements to improved boreal forest snow water equivalent retrievals  

Microsoft Academic Search

Four seasons (2004–2007) of snow surveys across the boreal forest of northern Manitoba were utilized to determine relationships between vertically polarized Advanced Microwave Scanning Radiometer (AMSR-E) brightness temperatures (TB) and ground measurements of snow water equivalent (SWE). Regression analysis identified moderate strength, yet statistically significant relationships between SWE and TB differences (36.5–18.7; 36.5–10.7; 18.7–10.7) for individual seasons. When multiple seasons

Chris Derksen

2008-01-01

68

PMMA Cementoplasty in Symptomatic Metastatic Lesions of the S1 Vertebral Body  

SciTech Connect

We describe a lateral transiliac direct puncture approach to the S1 vertebral body for polymethylmethacrylate (PMMA) cementoplasty of painful metastatic lesions. This approach was performed using a 15-cm-long trocar needle with 3-mm outer diameter, introduced under general anesthesia and fluoroscopic control. A lateral projection was used to center the needle just in front of the spinal canal and subjacent to the superior plate of the S1 vertebral body. Needle progression was controlled using anteroposterior and lateral fluoroscopic projections alternately with a needle course parallel to an axial plane, avoiding conflict with the S1 foramen. After needle tip placement in the center of the S1 vertebral body, diluted PMMA with a setting time of 8 min was delivered. Ipsilateral lesions of the lateral sacral compartment were filled with the same needle by stepwise withdrawal and continuous PMMA injection.

Dehdashti, Amir R.; Martin, Jean-Baptiste; Jean, Beatrix; Ruefenacht, Daniel A. [Neuroradiology-HUG, University Hospital of Geneva, CH-1211 Geneva 14 (Switzerland)

2000-03-15

69

Interaction of integrin ?4 with S1P receptors in S1P- and HGF-induced endothelial barrier enhancement.  

PubMed

We previously reported sphingosine 1-phosphate (S1P) and hepatocyte growth factor (HGF) augment endothelial cell (EC) barrier function and attenuate murine acute lung inury (ALI). While the mechanisms underlying these effects are not fully understood, S1P and HGF both transactivate the S1P receptor, S1PR1 and integrin ?4 (ITGB4) at membrane caveolin-enriched microdomains (CEMs). In the current study, we investigated the roles of S1PR2 and S1PR3 in S1P/HGF-mediated EC signaling and their associations with ITGB4. Our studies confirmed ITGB4 and S1PR2/3 are recruited to CEMs in human lung EC in response to either S1P (1?µM, 5?min) or HGF (25?ng/ml, 5?min). Co-immunoprecipitation experiments identified an S1P/HGF-mediated interaction of ITGB4 with both S1PR2 and S1PR3. We then employed an in situ proximity ligation assay (PLA) to confirm a direct ITGB4-S1PR3 association induced by S1P/HGF although a direct association was not detectable between S1PR2 and ITGB4. S1PR1 knockdown (siRNA), however, abrogated S1P/HGF-induced ITGB4-S1PR2 associations while there was no effect on ITGB4-S1PR3 associations. Moreover, PLA confirmed a direct association between S1PR1 and S1PR2 induced by S1P and HGF. Finally, silencing of S1PR2 significantly attenuated S1P/HGF-induced EC barrier enhancement as measured by transendothelial resistance while silencing of S1PR3 significantly augmented S1P/HGF-induced barrier enhancement. These results confirm an important role for S1PR2 and S1PR3 in S1P/HGF-mediated EC barrier responses that are associated with their complex formation with ITGB4. Our findings elucidate novel mechanisms of EC barrier regulation that may ultimately lead to new therapeutic targets for disorders characterized by increased vascular permeability including ALI. PMID:24851274

Ni, Xiuqin; Epshtein, Yulia; Chen, Weiguo; Zhou, Tingting; Xie, Lishi; Garcia, Joe G N; Jacobson, Jeffrey R

2014-06-01

70

WILL COMET ISON (C/2012 S1) SURVIVE PERIHELION?  

SciTech Connect

On 2013 November 28 Comet ISON (C/2012 S1) will pass by the Sun with a perihelion distance of 2.7 solar radii. Understanding the possible outcomes for the comet's response to such a close passage by the Sun is important for planning observational campaigns and for inferring ISON's physical properties. We present new numerical simulations and interpret them in context with the historical track record of comet disruptions and of sungrazing comet behavior. Historical data suggest that sizes below ?200 m are susceptible to destruction by sublimation driven mass loss, while we find that for ISON's perihelion distance, densities lower than 0.1 g cm{sup –3} are required to tidally disrupt a retrograde or non-spinning body. Such low densities are substantially below the range of the best-determined comet nucleus densities, though dynamically new comets such as ISON have few measurements of physical properties. Disruption may occur for prograde rotation at densities up to 0.7 g cm{sup –3}, with the chances of disruption increasing for lower density, faster prograde rotation, and increasing elongation of the nucleus. Given current constraints on ISON's nucleus properties and the typically determined values for these properties among all comets, we find tidal disruption to be unlikely unless other factors (e.g., spin-up via torquing) affect ISON substantially. Whether or not disruption occurs, the largest remnant must be big enough to survive subsequent mass loss due to sublimation in order for ISON to remain a viable comet well after perihelion.

Knight, Matthew M. [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States)] [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Walsh, Kevin J., E-mail: knight@lowell.edu [Southwest Research Institute, 1050 Walnut Street, Suite 400, Boulder, CO 80302 (United States)

2013-10-10

71

Vector-CM stable equilibrium analysis  

Microsoft Academic Search

The vector-constant modulus (VCM) criterion is an extension of the constant modulus (CM) criterion introduced recently for equalization of channels involving Gaussian sources. In this letter, we analyze the behavior of VCM for arbitrary source distributions and combined channel-receiver impulse responses of finite dimension. We begin by pointing out the difference between the VCM and CM cost functions and showing

Azzédine Touzni; L. Tong; R. A. Casas

2000-01-01

72

Astrophysics with the 60-cm telescope  

NASA Astrophysics Data System (ADS)

Observational programs and selection from scientific results with the 60-cm telescope achieved at the Skalnaté Pleso Observatory since its putting into operation is reviewed: novae, eclipsing and interacting binaries, symbiotic stars, cataclysmic variables, chemically peculiar stars, comets. Possible targets among newly detected binaries are proposed for determining orbital parameters using the new spectrograph of the 60-cm telescope at the Stará Lesná Observatory.

Zverko, J.

2014-03-01

73

Investigation of internal friction in fused quartz, steel, Plexiglass, and Westerly granite from 0.01 to 1.00 Hertz at 10- 8 to 10-7 strain amplitude.  

USGS Publications Warehouse

A detailed evaluation on the method of internal friction measurement by the stress-strain hysteresis loop method from 0.01 to 1 Hz at 10-8-10-7 strain amplitude and 23.9oC is presented. Significant systematic errors in relative phase measurement can result from convex end surfaces of the sample and stress sensor and from end surface irregularities such as nicks and asperities. Preparation of concave end surfaces polished to optical smoothness having a radius of curvature >3.6X104 cm reduces the systematic error in relative phase measurements to <(5.5+ or -2.2)X10-4 radians. -from Authors

Hsi-Ping, Liu; Peselnick, L.

1983-01-01

74

Study of ?(3S,2S)???(1S) and ?(3S,2S)??+?-?(1S) hadronic transitions  

NASA Astrophysics Data System (ADS)

We study the ?(3S,2S)???(1S) and ?(3S,2S)??+?-?(1S) transitions with 122×106?(3S) and 100×106?(2S) mesons collected by the BABAR detector at the PEP-II asymmetric-energy e+e- collider. We measure B[?(2S)???(1S)]=(2.39±0.31(stat.)±0.14(syst.))×10-4 and ?[?(2S)???(1S)]/?[?(2S)??+?-?(1S)]=(1.35±0.17(stat.)±0.08(syst.))×10-3. We find no evidence for ?(3S)???(1S) and obtain B[?(3S)???(1S)]<1.0×10-4 and ?[?(3S)???(1S)]/?[?(3S)??+?-?(1S)]<2.3×10-3 as upper limits at the 90% confidence level. We also provide improved measurements of the ?(2S)-?(1S) and ?(3S)-?(1S) mass differences, 562.170±0.007(stat.)±0.088(syst.)MeV/c2 and 893.813±0.015(stat.)±0.107(syst.)MeV/c2, respectively.

Lees, J. P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Milanes, D. A.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Brown, D. N.; Kerth, L. T.; Kolomensky, Yu. G.; Lynch, G.; Koch, H.; Schroeder, T.; Asgeirsson, D. J.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Khan, A.; Blinov, V. E.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Kravchenko, E. A.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Yushkov, A. N.; Bondioli, M.; Kirkby, D.; Lankford, A. J.; Mandelkern, M.; Stoker, D. P.; Atmacan, H.; Gary, J. W.; Liu, F.; Long, O.; Vitug, G. M.; Campagnari, C.; Hong, T. M.; Kovalskyi, D.; Richman, J. D.; West, C. A.; Eisner, A. M.; Kroseberg, J.; Lockman, W. S.; Martinez, A. J.; Schalk, T.; Schumm, B. A.; Seiden, A.; Cheng, C. H.; Doll, D. A.; Echenard, B.; Flood, K. T.; Hitlin, D. G.; Ongmongkolkul, P.; Porter, F. C.; Rakitin, A. Y.; Andreassen, R.; Dubrovin, M. S.; Huard, Z.; Meadows, B. T.; Sokoloff, M. D.; Sun, L.; Bloom, P. C.; Ford, W. T.; Gaz, A.; Nagel, M.; Nauenberg, U.; Smith, J. G.; Wagner, S. R.; Ayad, R.; Toki, W. H.; Spaan, B.; Kobel, M. J.; Schubert, K. R.; Schwierz, R.; Bernard, D.; Verderi, M.; Clark, P. J.; Playfer, S.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cibinetto, G.; Fioravanti, E.; Garzia, I.; Luppi, E.; Munerato, M.; Negrini, M.; Piemontese, L.; Santoro, V.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Nicolaci, M.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; Zallo, A.; Contri, R.; Guido, E.; Lo Vetere, M.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Bhuyan, B.; Prasad, V.; Lee, C. L.; Morii, M.; Edwards, A. J.; Adametz, A.; Marks, J.; Uwer, U.; Bernlochner, F. U.; Ebert, M.; Lacker, H. M.; Lueck, T.; Dauncey, P. D.; Tibbetts, M.; Behera, P. K.; Mallik, U.; Chen, C.; Cochran, J.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Rubin, A. E.; Gritsan, A. V.; Guo, Z. J.; Arnaud, N.; Davier, M.; Grosdidier, G.; Le Diberder, F.; Lutz, A. M.; Malaescu, B.; Roudeau, P.; Schune, M. H.; Stocchi, A.; Wormser, G.; Lange, D. J.; Wright, D. M.; Bingham, I.; Chavez, C. A.; Coleman, J. P.; Fry, J. R.; Gabathuler, E.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; di Lodovico, F.; Sacco, R.; Sigamani, M.; Cowan, G.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Hafner, A.; Prencipe, E.; Alwyn, K. E.; Bailey, D.; Barlow, R. J.; Jackson, G.; Lafferty, G. D.; Behn, E.; Cenci, R.; Hamilton, B.; Jawahery, A.; Roberts, D. A.; Simi, G.; Dallapiccola, C.; Cowan, R.; Dujmic, D.; Sciolla, G.; Lindemann, D.; Patel, P. M.; Robertson, S. H.; Schram, M.; Biassoni, P.; Lazzaro, A.; Lombardo, V.; Neri, N.; Palombo, F.; Stracka, S.; Cremaldi, L.; Godang, R.; Kroeger, R.; Sonnek, P.; Summers, D. J.; Nguyen, X.; Taras, P.; de Nardo, G.; Monorchio, D.; Onorato, G.; Sciacca, C.; Raven, G.; Snoek, H. L.; Jessop, C. P.; Knoepfel, K. J.; Losecco, J. M.; Wang, W. F.; Honscheid, K.; Kass, R.; Brau, J.; Frey, R.; Sinev, N. B.; Strom, D.; Torrence, E.; Feltresi, E.; Gagliardi, N.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Stroili, R.; Akar, S.; Ben-Haim, E.; Bomben, M.; Bonneaud, G. R.; Briand, H.; Calderini, G.; Chauveau, J.; Hamon, O.; Leruste, Ph.; Marchiori, G.; Ocariz, J.; Sitt, S.; Biasini, M.; Manoni, E.; Pacetti, S.; Rossi, A.; Angelini, C.; Batignani, G.; Bettarini, S.; Carpinelli, M.; Casarosa, G.; Cervelli, A.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Oberhof, B.; Paoloni, E.; Perez, A.; Rizzo, G.; Walsh, J. J.; Lopes Pegna, D.; Lu, C.; Olsen, J.; Smith, A. J. S.; Telnov, A. V.; Anulli, F.; Cavoto, G.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Gaspero, M.; Li Gioi, L.; Mazzoni, M. A.; Piredda, G.; Bünger, C.; Grünberg, O.; Hartmann, T.; Leddig, T.; Schröder, H.; Waldi, R.; Adye, T.; Olaiya, E. O.; Wilson, F. F.; Emery, S.; Hamel de Monchenault, G.; Vasseur, G.; Yèche, Ch.; Aston, D.; Bard, D. J.; Bartoldus, R.; Cartaro, C.; Convery, M. R.; Dorfan, J.; Dubois-Felsmann, G. P.; Dunwoodie, W.; Field, R. C.; Franco Sevilla, M.; Fulsom, B. G.; Gabareen, A. M.; Graham, M. T.; Grenier, P.; Hast, C.; Innes, W. R.; Kelsey, M. H.; Kim, H.; Kim, P.; Kocian, M. L.; Leith, D. W. G. S.; Lewis, P.; Li, S.; Lindquist, B.; Luitz, S.; Luth, V.; Lynch, H. L.; Macfarlane, D. B.; Muller, D. R.; Neal, H.; Nelson, S.; Ofte, I.; Perl, M.; Pulliam, T.; Ratcliff, B. N.; Roodman, A.; Salnikov, A. A.; Schindler, R. H.; Snyder, A.; Su, D.; Sullivan, M. K.; Va'Vra, J.; Wagner, A. P.; Weaver, M.; Wisniewski, W. J.; Wittgen, M.; Wright, D. H.; Wulsin, H. W.; Yarritu, A. K.; Young, C. C.; Ziegler, V.; Park, W.; Purohit, M. V.; White, R. M.; Wilson, J. R.; Randle-Conde, A.; Sekula, S. J.; Bellis, M.; Benitez, J. F.; Burchat, P. R.; Miyashita, T. S.

2011-11-01

75

The Coulomb and c.m. corrections to the nuclear Hartree-Fock calculations  

Microsoft Academic Search

The effects of the Coulomb and c.m. corrections on the Hartree-Fock calculations are explicitly evaluated for several nuclei in the 2s-1d shell. It is seen that the c.m. correction is quite significant for the energies of the lower single-particle Hartree-Fock orbitals and the overall correction to the binding energy can be expressed in the form (a\\/A)exp (-bA), where A is

M. R. Gunye

1968-01-01

76

Chilled Mirror Dew Point Hygrometer (CM) Handbook  

SciTech Connect

The CM systems have been developed for the ARM Program to act as a moisture standard traceable to National Institute of Standards and Technology (NIST). There are three CM systems that are each fully portable, self-contained, and require only 110 V AC power. The systems include a CM sensor, air sampling and filtration system, a secondary reference (Rotronic HP043 temperature and relative humidity sensor) to detect system malfunctions, a data acquisition system, and data storage for more than one month of 1-minute data. The CM sensor directly measures dew point temperature at 1 m, air temperature at 2 m, and relative humidity at 2 m. These measurements are intended to represent self-standing data streams that can be used independently or in combinations.

Ritsche, MT

2005-01-01

77

Polyhedral Serpentine Grains in CM Chondrites.  

National Technical Information Service (NTIS)

CM chondrites are primitive rocks that experienced aqueous alteration in the early solar system. Their matrices and fine-grained rims (FGRs) sustained the effects of alteration, and the minerals within them hold clues to the aqueous reactions. Sheet silic...

T. J. Zega L. A. J. Garvie I. Dodony R. M. Stroud

2005-01-01

78

A novel mGluR5 antagonist, MFZ 10-7, inhibits cocaine-taking and cocaine-seeking behavior in rats.  

PubMed

Pre-clinical studies suggest that negative allosteric modulators (NAMs) of the metabotropic glutamate receptor subtype 5 (mGluR5), including 2-methyl-6-(phenylethynyl)pyridine (MPEP), 3-[(2-methyl-1,3-thiazol-4-yl)ethynyl]pyridine (MTEP) and fenobam are highly effective in attenuating drug-taking and drug-seeking behaviors. However, both MPEP and MTEP have no translational potential for use in humans because of their off-target effects and short half-lives. Here, we report that 3-fluoro-5-[(6-methylpyridin-2-yl)ethynyl]benzonitrile (MFZ 10-7), a novel mGluR5 NAM, is more potent and selective than MPEP, MTEP and fenobam in both in vitro binding and functional assays. Similar to MTEP, intraperitoneal administration of MFZ 10-7 inhibited intravenous cocaine self-administration, cocaine-induced reinstatement of drug-seeking behavior and cocaine-associated cue-induced cocaine-seeking behavior in rats. Although MFZ 10-7 and MTEP lowered the rate of oral sucrose self-administration, they did not alter total sucrose intake. Further, MFZ 10-7 appeared to be more potent than MTEP in inducing downward shifts in the cocaine dose-response curve, but less effective than MTEP in attenuating sucrose-induced reinstatement of sucrose-seeking behavior. MFZ 10-7 and MTEP had no effect on basal locomotor behavior. These findings not only provide additional evidence supporting an important role for mGluR5 in cocaine reward and addiction, but also introduce a new tool for both in vitro and in vivo investigations with which to further characterize this role. PMID:24001208

Keck, Thomas M; Zou, Mu-Fa; Bi, Guo-Hua; Zhang, Hai-Ying; Wang, Xiao-Fei; Yang, Hong-Ju; Srivastava, Ratika; Gardner, Eliot L; Xi, Zheng-Xiong; Newman, Amy Hauck

2014-03-01

79

S1P(4) receptor mediates S1P-induced vasoconstriction in normotensive and hypertensive rat lungs.  

PubMed

This study aimed to identify receptors mediating sphingosine-1-phosphate (S1P)-induced vasoconstriction in the normotensive and chronic hypoxia-induced hypertensive rat pulmonary circulation. In isolated perfused lungs from normoxic rats, infusion of S1P caused a sustained vasoconstriction, which was not reduced by combinational pretreatment with the dual S1P(1 and 3) receptor antagonist VPC23019 and the S1P(2) receptor antagonist JTE013. The S1P(4) receptor agonists phytosphingosine-1-phospate and VPC23153, but not the dual S1P(1 and 3) receptor agonist VPC24191, caused dose-dependent vasoconstrictions. In hypertensive lungs from chronically hypoxic rats, the vasoconstrictor responses to S1P and VPC23153 were markedly enhanced. The S1P(4) receptor agonist VPC 23153 caused contraction of isolated pulmonary but not of renal or mesenteric arteries from chronically hypoxic rats. S1P(4) receptor protein as well as mRNA were detected in both normotensive and hypertensive pulmonary arteries. In contrast to what has been reported in the systemic circulation and mouse lung, our findings raise the possibility that S1P(4) receptor plays a significant role in S1P-induced vasoconstriction in the normotensive and hypertensive rat pulmonary circulation. PMID:22140630

Ota, Hiroki; Beutz, Michelle A; Ito, Masako; Abe, Kohtaro; Oka, Masahiko; McMurtry, Ivan F

2011-01-01

80

Detection of Thermal 2 cm and 1 cm Formaldehyde Emission in NGC 7538  

NASA Astrophysics Data System (ADS)

Formaldehyde is a tracer of high density gas in massive star forming regions. The K-doublet lines from the three lowest rotational energy levels of ortho-formaldehyde correspond to wavelengths of 6, 2 and 1 cm. Thermal emission of these transitions is rare, and maser emission has only been detected in the 6 cm line. NGC 7538 is an active site of massive star formation in the Galaxy, and one of only a few regions known to harbor 6 cm formaldehyde (H2CO) masers. Using the NRAO 100 m Green Bank Telescope (GBT), we detected 2 cm H2CO emission toward NGC 7538 IRS1. The velocity of the 2 cm H2CO line is very similar to the velocity of one of the 6 cm H2CO masers but the linewidth is greater. To investigate the nature of the 2 cm emission, we conducted observations of the 1 cm H2CO transition, and obtained a cross-scan map of the 2 cm line. We detected 1 cm emission and found that the 2 cm emission is extended (greater than 30"), which implies brightness temperatures of ˜0.2 K. Assuming optically thin emission, LTE, and that the 1 cm and 2 cm lines originate from the same volume of gas, both these detections are consistent with thermal emission of gas at ˜30 K. We conclude that the 1 cm and 2 cm H2CO lines detected with the GBT are thermal, which implies molecular densities above ˜105 cm-3. LY acknowledges support from WIU. PH acknowledges partial support from NSF grant AST-0908901.

Yuan, Liang; Araya, E. D.; Hofner, P.; Kurtz, S.; Pihlstrom, Y.

2011-05-01

81

21-cm line observations of galaxies from Kazarian's lists  

NASA Astrophysics Data System (ADS)

The 21-cm neutral hydrogen line has been measured for the first time in 39 non-Seyfert type galaxies from Kazarian list, with the Nancay radiotelescope. The line profiles, widths at 20% and 50% of the peak intensity, radial velocities as well as total fluxes are presented. The values of radial velocity are in fairly good agreement with those obtained from optical spectra. The width values at 20% of the peak vary in wide range from 113 km s^{-1} (KAZ 579) to 608 km s^{-1} for KAZ 566. Nine of our objects remained undetected, whether their HI-flux was too faint, the integration time too short, or the frequency sighted wrong. However, for part of them, there were positive hint of detection. Comments on individual objects are given. Tables 1 and 3 are only available in electronic form at CDS. Table 2 is also available in electronic form at CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html

Tamazian, V. S.; Theureau, G.; Coudreau-Durand, N.

1997-12-01

82

Cross section for 246Cm subbarrier fission  

NASA Astrophysics Data System (ADS)

The cross section for 246Cm fission induced by neutrons of energy in the range 0.1 eV-20 keV was measured by the neutron lead slowing-down spectrometer (LSDS-100) of the Institute for Nuclear Research (INR, Russian Academy of Sciences, Moscow). The parameters of the resonance area and of the fission width were evaluated for several low-lying s-wave neutron resonances. The parameters of the intermediate structure in the cross section for the subbarrier fusion of 246Cm nuclei were found. The results obtained in this way were compared with available experimental data and with recommended evaluated data.

Alekseev, A. A.; Bergman, A. A.; Berlev, A. I.; Koptelov, E. A.; Samylin, B. F.; Trufanov, A. M.; Fursov, B. I.; Shorin, V. S.

2010-10-01

83

The Parkes 21 CM multibeam receiver  

NASA Astrophysics Data System (ADS)

Several extragalactic HI surveys using a 21-cm 13-beam focal plane array will begin in late 1996 using the Parkes 64-m telescope. These surveys are designed to detect efficiently nearby galaxies that have failed to be identified optically because of low optical surface brightness or high optical extinction. We discuss scientific and technical aspects of the multibeam receiver including astronomical objectives, feed, receiver and correlator design and data acquisition. A comparison with other telescopes shows that the Parkes multibeam receiver has significant speed advantages for any large-area 21- cm galaxy survey in the velocity range range 0 - 14000 km per sec.

Staveley-Smith, L.; Wilson, W. E.; Bird, T. S.; Disney, M. J.; Ekers, R. D.; Freeman, K. C.; Haynes, R. F.; Sinclair, M. W.; Vaile, R. A.; Webster, R. L.; Wright, A. E.

1996-11-01

84

Determination of the threshold value of F10.7 in the dependence of foF2 on solar activity  

NASA Astrophysics Data System (ADS)

By introducing the two-segmented linear regression model instead of the well known quadratic fit, we were able to describe the solar activity dependence of the F2 critical frequency. Saturation features were observed and the corresponding F10.7 values at which this phenomenon occurs were obtained for different hours. The seasonal average values were found to be around 154 sfu, 138 sfu, 177 sfu and 150 sfu for March equinox, June solstice, September equinox and December solstice respectively. These affirmed that saturation phenomenon is more pronounced at the equinoxes than solstices. On the average, the threshold value of F10.7 was obtained to be 154.5 sfu for this station in the African sector of the equatorial region.

Adeniyi, J. O.; Ikubanni, S. O.

2013-05-01

85

Static compression of Ca(OH)2 at room temperature - Observations of amorphization and equation of state measurements to 10.7 GPa  

NASA Technical Reports Server (NTRS)

X-ray diffraction measurements are reported for Ca(OH)2 portlandite as it is compressed to 37.6 GPa in the diamond cell at room temperature. Between 10.7 and 15.4 GPa crystalline Ca(OH)2 transforms to a glass, and on decompression the glass recrystallizes between 3.6 and 5.1 GPa. Below pressures of 10.7 GPa the elastic compression of crystalline Ca(OH)2 was measured. A finite strain analysis of these data shows that the isothermal bulk modulus and its pressure derivative are 37.8 + or - 1.8 GPa and 5.2 + or - 0.7 at zero pressure. The change in the unit cell dimensions indicates that the linear incompressibilities of Ca(OH)2 differ by a factor of three.

Meade, Charles; Jeanloz, Raymond

1990-01-01

86

Characterization of 8-cm engineering model thruster  

NASA Technical Reports Server (NTRS)

Development of 8 cm ion thruster technology which was conducted in support of the Ion Auxiliary Propulsion System (IAPS) flight contract (Contract NAS3-21055) is discussed. The work included characterization of thruster performance, stability, and control; a study of the effects of cathode aging; environmental qualification testing; and cyclic lifetesting of especially critical thruster components.

Williamson, W. S.

1984-01-01

87

The Multidimensional Curriculum Model (MdCM)  

ERIC Educational Resources Information Center

The multidimensional Curriculum Model (MdCM) helps teachers to better prepare gifted and able students for our changing world, acquiring much needed skills. It is influenced by general learning theory of constructivism, notions of preparing students for 21st century, Teaching the Future Model, and current comprehensive curriculum models for…

Vidergor, Hava E.

2010-01-01

88

Equatorial evening prereversal vertical drift dependence on solar EUV flux and F10.7 index during quiet and disturbed periods over Brazil  

NASA Astrophysics Data System (ADS)

A study of the dependence of the equatorial evening F region vertical drift velocity on solar EUV flux and F10.7 index is presented here, based on the vertical drift data obtained from Digisondes operated in São Luis (44.2° W, 2.33° S, dip angle: -2.7°) and Fortaleza (38.45° W, 3.9° S, dip angle: -11.5°) in Brazil. Previous studies on the vertical drift dependence on solar flux have addressed only the dependence on F10.7 index. The data analyzed here are from the months of October, November, and December of the years from 2001 to 2009, and the analysis was done for magnetically quiet and disturbed conditions. The results show that while the drift velocity peak is strongly dependent on both solar emission fluxes, the degrees of such dependence are higher for the EUV flux than for the F10.7 index in a consistent way as judged from its identical behavior at both São Luis and Fortaleza. The study also reveals different degrees of the vertical drift dependence on solar flux for magnetically quiet and disturbed conditions, the nature of which is investigated using an example of a storm time case study.

Santos, A. M.; Abdu, M. A.; Sobral, J. H. A.; Mascarenhas, M.; Nogueira, P. A. B.

2013-07-01

89

Stomach Cancer Drug, S-1, Shows Promise in Japanese Trial  

Cancer.gov

In this Japanese clinical trial, patients with advanced, inoperable stomach cancer who received combination therapy with cisplatin and a drug called S-1 lived about two months longer than patients treated with S-1 alone, according to the March 2008 Lancet Oncology.

90

Measurements of Output Factors For Small Photon Fields Up to 10 cm x 10 cm  

NASA Astrophysics Data System (ADS)

Field output factors (OF) for photon beams from a 6 MV medical accelerator were measured using five different detectors in a scanning water phantom. The measurements were taken for square field sizes of integral widths ranging from 1 cm to 10 cm for two reference source-to-surface distances (SSD) and depths in water. For the diode detectors, square field widths as small as 2.5 mm were also studied. The photon beams were collimated by using either the jaws or the multileaf collimators. Measured OFs are found to depend upon the field size, SSD, depth and also upon the type of beam collimation, size and type of detector used. For field sizes larger than 3 cm x 3 cm, the OF measurements agree to within 1% or less. The largest variation in OF occurs for jawsshaped field of size 1 cm x 1cm, where a difference of more than 18% is observed.

Bacala, Angelina

91

Power Spectrum Estimation for 21 cm Cosmology  

NASA Astrophysics Data System (ADS)

Tomography with the 21 cm line of neutral hydrogen presents the opportunity to directly probe a vast fraction of the comoving volume of the observable universe at times when more established techniques are unavailable. The power spectrum of 21 cm brightness temperature fluctuations from the Epoch of Reionization and preceding eras will likely be the first key measurement for comparing theory and observation and constraining models of astrophysics and cosmology during the Cosmic Dawn. In this poster, I will present the statistical and algorithmic challenges presented by making this measurement in the presence of foregrounds that are orders of magnitude stronger than the signal. I will also show progress that has been made to overcome these challenges with data from the Murchinson Widefield Array and the implication for future experiments and analysis techniques.

Dillon, Joshua S.

2014-06-01

92

Extended Performance 8-cm Mercury Ion Thruster  

NASA Technical Reports Server (NTRS)

A slightly modified 8-cm Hg ion thruster demonstrated significant increase in performance. Thrust was increased by almost a factor of five over that of the baseline thruster. Thruster operation with various three grid ion optics configurations; thruster performance as a function of accelerator grid open area, cathode baffle, and cathode orifice size; and a life test of 614 hours at a beam current of 250 mA (17.5 mN thrust) are discussed. Highest thruster efficiency was obtained with the smallest open area accelerator grid. The benefits in efficiency from the low neutral loss grids were mitigated, however, by the limitation such grids place on attainable ion beam current densities. The thruster components suffered negligible weight losses during a life test, which indicated that operation of the 8-cm thruster at extended levels of thrust and power is possible with no significant loss of lifetime.

Mantenieks, M. A.

1981-01-01

93

On absolute CM-periods, II  

Microsoft Academic Search

For a CM-fieldK, Shimura defined the period symbolpK by factorizing periods of abelian varieties with complex multiplication. We define the absolute period symbolgK using division values of the multiple gamma function and conjecture that pK coincides with gK up to the multiplication by algebraic numbers. Taking the action of Gal(Q Q) into account, we present a refined version of this

Hiroyuki Yoshida

1998-01-01

94

Polyhedral Serpentine Grains in CM Chondrites  

NASA Technical Reports Server (NTRS)

CM chondrites are primitive rocks that experienced aqueous alteration in the early solar system. Their matrices and fine-grained rims (FGRs) sustained the effects of alteration, and the minerals within them hold clues to the aqueous reactions. Sheet silicates are an important product of alteration, and those of the serpentine group are abundant in the CM2 chondrites. Here we expand on our previous efforts to characterize the structure and chemistry of serpentines in CM chondrites and report results on a polyhedral form that is structurally similar to polygonal serpentine. Polygonal serpentine consists of tetrahedral (T) sheets joined to M(2+)-centered octahedral (O) sheets (where (M2+) is primarily Mg(2+) and Fe(2+)), which give rise to a 1:1 (TO) layered structure with a 0.7-nm layer periodicity. The structure is similar to chrysotile in that it consists of concentric lizardite layers wrapped around the fiber axis. However, unlike the rolled-up chrysotile, the tetrahedral sheets of the lizardite layers are periodically inverted and kinked, producing sectors. The relative angles between sectors result in 15- and 30-sided polygons in terrestrial samples.

Zega, Thomas J.; Garvie, Laurence A. J.; Dodony, Istvan; Stroud, Rhonda M.; Buseck, Peter R.

2005-01-01

95

Overcoming the Challenges of 21cm Cosmology  

NASA Astrophysics Data System (ADS)

The highly-redshifted 21cm line of neutral hydrogen is one of the most promising and unique probes of cosmology for the next decade and beyond. The past few years have seen a number of dedicated experiments targeting the 21cm signal from the Epoch of Reionization (EoR) begin operation, including the LOw-Frequency ARray (LOFAR), the Murchison Widefield Array (MWA), and the Donald C. Backer Precision Array for Probing the Epoch of Reionization (PAPER). For these experiments to yield cosmological results, they require new calibration and analysis algorithms which will need to achieve unprecedented levels of separation between the 21cm signal and contaminating foreground emission. Although much work has been spent developing these algorithms over the past decade, their success or failure will ultimately depend on their ability to overcome the complications associated with real-world systems and their inherent complications. The work in this dissertation is closely tied to the late-stage commissioning and early observations with PAPER. The first two chapters focus on developing calibration algorithms to overcome unique problems arising in the PAPER system. To test these algorithms, I rely on not only simulations, but on commissioning observations, ultimately tying the success of the algorithm to its performance on actual, celestial data. The first algorithm works to correct gain-drifts in the PAPER system caused by the heating and cooling of various components (the amplifiers and above ground co-axial cables, in particular). It is shown that a simple measurement of the ambient temperature can remove ˜ 10% gain fluctuations in the observed brightness of calibrator sources. This result is highly encouraging for the ability of PAPER to remove a potentially dominant systematic in its power spectrum and cataloging measurements without resorting to a complicated system overhaul. The second new algorithm developed in this dissertation solves a major calibration challenge not just for PAPER, but for nearly all of a large class of new wide-field, drift- scanning radio telescopes: primary beam calibration in the presence of a poorly measured sky. Since these telescopes lack the ability to steer their primary beams, while seeing nearly the entire sky at once, a large number of calibrator sources are necessary to probe the entire beam response. However, the catalogs of radio sources at low-frequencies are not reliable enough to achieve the level of primary beam accuraccy needed for 21cm cosmology experiments. I develop, test, and apply a new technique which -- using only the assumption of symmetry around a 180° rotation -- simultaneously solves for the primary beam and the flux density of large number of sources. In this dissertation, I also present the analysis of new observations from PAPER to test theoretical models which predict foreground emission is confined to a "wedge"-like region of cosmological Fourier space, leaving an "EoR window" free from contamination. For the first time in actual observations, these predictions are spectacularly confirmed. In many ways, this result shifts the burden for upcoming PAPER analysis from foreground removal to increased sensitivity. And although increasing sensitivity is no small feat in-and-of-itself, this result is highly encouraging for 21cm studies, as foreground removal was long-viewed as the principal challenge for this field. The final result in this dissertation is the application of the all the lessons learned building PAPER and the MWA to design a new experiment for 21cm studies at z ˜ 1 with the goal of measuring baryon acoustic oscillations (BAO). The design of the BAO Broadband and Broad-beam (BAOBAB) Array is described, and cosmological forecasts are presented. The bottom line is highly encouraging, suggesting that z ˜ 1 21cm observations can detect the neutral hydrogen power spectrum with a very modest (16 - 32 element) array, and that still reasonably sized (128 - 256 elements) arrays can produce significant advances in our knowledge of dark energy.

Pober, Jonathan

96

[Family of ribosomal proteins S1 contains unique conservative domain].  

PubMed

Different representatives of bacteria have different number of amino acid residues in the ribosomal proteins S1. This number varies from 111 (Spiroplasma kunkelii) to 863 a.a. (Treponema pallidum). Traditionally and for lack of this protein three-dimensional structure, its architecture is represented as repeating S1 domains. Number of these domains depends on the protein's length. Domain's quantity and its boundaries data are contained in the specialized databases, such as SMART, Pfam and PROSITE. However, for the same object these data may be very different. For search of domain's quantity and its boundaries, new approach, based on the analysis of dicted secondary structure (PsiPred), was used. This approach allowed us to reveal structural domains in amino acid sequences of S1 proteins and at that number varied from one to six. Alignment of S1 proteins, containing different domain's number, with the S1 RNAbinding domain of Escherichia coli PNPase elicited a fact that in family of ribosomal proteins SI one domain has maximal homology with S1 domain from PNPase. This conservative domain migrates along polypeptide chain and locates in proteins, containing different domain's number, according to specified pattern. In this domain as well in the S1 domain from PNPase, residues Phe-19, Phe-22, His-34, Asp-64 and Arg-68 are clustered on the surface and formed RNA binding site. PMID:20873233

Deriusheva, E I; Machulin, A V; Selivanova, O M; Serdiuk, I N

2010-01-01

97

Theoretical variability of s1 in the tide generating potential  

NASA Astrophysics Data System (ADS)

The S1 tidal wave arising from the second order tidal potential occurs in any geophysical data record. Since the frequency of S1 is the same as that of earth’s rotation, many distortions are observed in real data sets. To isolate S1 from its powerful neighbours, K 1 and P1 at least one-year hourly data series are required. Studies on S 1 on an experimental basis, have been aimed mainly at a precise determination of its origin and mechanisms of variability. There are many hypotheses on its variability. In physical oceanography it is commonly accepted that the variability of S1 is due to air-sea interaction processes. The authors review most existing hypotheses on the variability of S1 They also show that the distortions of real data must be expected due to additional contributions from the second and third-order lunar potentials. An analysis is made to detect the sources of the additional contributions to the S1 frequency.

Alonso, J. J.; Bruno, M.; Mañanes, R.

1997-12-01

98

ICD-10 to ICD-10-CM Based on FY2014 ICD-10-CM codes  

Cancer.gov

ICD-10 to ICD-10-CM Based on FY2014 ICD-10-CM codes REPORTABLE NEOPLASMS Category and subcategory codes are shaded in grey and marked with an ^ Cells shaded in pink and marked with an *indicate the preferred code when a single code maps to multiple codes

99

ICD-10 to ICD-9-CM Based on FY2014 ICD-9-CM codes  

Cancer.gov

ICD-10 to ICD-9-CM Based on FY2014 ICD-9-CM codes REPORTABLE NEOPLASMS Category and subcategory codes are shaded in grey and marked with an ^ Cells shaded in pink and marked with an *indicate the preferred code when a single code maps to multiple codes

100

ICD-10-CM to ICD-10 Based on FY2014 ICD-10-CM codes  

Cancer.gov

ICD-10-CM to ICD-10 Based on FY2014 ICD-10-CM codes REPORTABLE NEOPLASMS Category and subcategory codes are shaded in grey and marked with an ^ Cells shaded in pink and marked with an *indicate the preferred code when a single code maps to multiple codes

101

Screening and identification of a Bacillus thuringiensis strain S1/4 with large and efficient insecticidal activities.  

PubMed

The bacterium Bacillus thuringiensis was recognized for its entomopathogenic activities related to Cry and Cyt proteins forming the ?-endotoxins and some extracellular activities like the vegetative insecticidal proteins (VIP) and Cry1I. These activities may act specifically against diverse organisms and some of them typically characterize each strain. Here, we screened a set of 212 B. thuringiensis strains to search the higher insecticidal activities. These strains had bipyramidal and cubic crystal morphologies and 30% of them showed PCR amplification of vip3 internal region, from which five isolates (S1/4, S17, S122, S123, and S144) showed plasmid profile variability. These five strains contained the cry1I, cry1Aa and/or cry1Ac, cry1Ab and cry2 genes, and S1/4 harbored in addition the cry1C, vip1, and vip2 genes. They produced from 25 to 46 µg ?-endotoxin per 10(7) spores. Their ?-endotoxins displayed distinct lethal concentrations 50% against either Spodoptera littoralis or Ephestia kuehniella larvae with the lowest one for S1/4, which was also active against Tuta absoluta. Fortunately, the analysis of the culture supernatants revealed that S1/4 had the higher toxicity towards these lepidopteron but it did not show any toxicity against the Tribolium castaneum coleopteran larvae; additionally, S1/4 displayed an antibacterial activity. S1/4 is a good candidate for agricultural pest control, as it is more efficient than the reference strain HD1. PMID:22915162

Sellami, Sameh; Zghal, Taheni; Cherif, Maroua; Zalila-Kolsi, Imen; Jaoua, Samir; Jamoussi, Kaïs

2013-06-01

102

Jet spectroscopy of pyrene complexes: Unusual complexation shifts in the S 0 ? S 1 spectrum  

NASA Astrophysics Data System (ADS)

The fluorescence excitation spectra of pyrene complexes with n-alkanes are reported for the S 0 ? S 1 and S 0 ? S 2 transitions. The S 2 spectral shifts are predictable from theory, and by comparison with other molecules, such as perylene. On the other hand, the S 1 Resonances of pyrene complexes show unusually small displacements from those of the parent species. The spectra of the butane, pentane and hexane complexes actually exhibit net blue shifts. This behaviour provides good evidence for a repulsive interaction in the S 1 state, which is not observed in S 2. Moreover, because the butadiene and benzene complexes give predictable red shifts ? 100 cm -1, and these are found to have plane-parallel geometries, the blue shift correlates with a host carbon—guest hydrogen interaction in the repulsive regime. We also report that the ethylene complex of pyrene exhibits a net blue shift on the S 0 ? S 1 transition, and a red shift on S 0 ? S 2 only 75% of the predicted value, based on measurements with perylene complexes. This behaviour strongly indicates that ethylene-pyrene has a T-shaped configuration, as predicted by potential energy calculations.

Mangle, Elisa A.; Topp, Michael R.

1987-03-01

103

A 30-cm diameter argon ion source  

NASA Technical Reports Server (NTRS)

A 30 cm diameter argon ion source was evaluated. Ion source beam currents up to 4a were extracted with ion energies ranging from 0.2 to 1.5 KeV. An ion optics scaling relation was developed for predicting ion beam extraction capability as a function of total extraction voltage, gas type, and screen grid open area. Ignition and emission characteristics of several hollow cathode geometries were assessed for purposes of defining discharge chamber and neutralizer cathodes. Also presented are ion beam profile characteristics which exhibit broad beam capability well suited for ion beam sputtering applications.

Sovey, J. S.

1976-01-01

104

S-1-based combination therapy vs S-1 monotherapy in advanced gastric cancer: A meta-analysis  

PubMed Central

AIM: To assess the efficacy and safety of combination therapy based on S-1, a novel oral fluoropyrimidine, vs S-1 monotherapy in advanced gastric cancer (AGC). METHODS: We searched PubMed, EMBASE and the Cochrane Library for eligible studies published before March 2013. Our analysis identified four randomized controlled trials involving 790 participants with AGC. The outcome measures were overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and grade 3-4 adverse events. RESULTS: Meta-analysis showed that S-1-based combination therapy significantly improved OS (HR = 0.77, 95%CI: 0.66-0.91, P = 0.002), PFS (HR = 0.58, 95%CI: 0.46-0.72, P = 0.000) and ORR (OR = 2.23, 95%CI: 1.54-3.21, P = 0.000). Sensitivity analysis further confirmed this association. Lower incidence of grade 3-4 leucopenia (OR = 4.06, 95%CI: 2.11-7.81), neutropenia (OR = 3.94, 95%CI: 2.1-7.81) and diarrhea (OR = 2.41, 95%CI: 1.31-4.44) was observed in patients with S-1 monotherapy. CONCLUSION: S-1-based combination therapy is superior to S-1 monotherapy in terms of OS, PFS and ORR. S-1 monotherapy is associated with less toxicity.

Liu, Guo-Fang; Tang, Dong; Li, Ping; Wang, Su; Xu, Ya-Xiang; Long, Ai-Hua; Zhou, Nian-Lan; Zhang, Li-Li; Chen, Jie; Xiang, Xiao-Xing

2014-01-01

105

30-cm electron cyclotron plasma generator  

NASA Technical Reports Server (NTRS)

Experimental results on the development of a 30-cm-diam electron cyclotron resonance plasma generator are presented. This plasma source utilizes samarium-cobalt magnets and microwave power at a frequency of 4.9 GHz to produce a uniform plasma with densities of up to 3 x 10 to the 11th/cu cm in a continuous fashion. The plasma generator contains no internal structures, and is thus inherently simple in construction and operation and inherently durable. The generator was operated with two different magnetic geometries. One used the rare-earth magnets arranged in an axial line cusp configuration, which directly showed plasma production taking place near the walls of the generator where the electron temperature was highest but with the plasma density peaking in the central low B-field regions. The second configuration had magnets arranged to form azimuthal line cusps with approximately closed electron drift surfaces; this configuration showed an improved electrical efficiency of about 135 eV/ion.

Goede, Hank

1987-01-01

106

THE METALLICITY OF THE CM DRACONIS SYSTEM  

SciTech Connect

The CM Draconis system comprises two eclipsing mid-M dwarfs of nearly equal mass in a 1.27 day orbit. This well-studied eclipsing binary has often been used for benchmark tests of stellar models, since its components are among the lowest mass stars with well-measured masses and radii ({approx}< 1% relative precision). However, as with many other low-mass stars, non-magnetic models have been unable to match the observed radii and effective temperatures for CM Dra at the 5%-10% level. To date, the uncertain metallicity of the system has complicated comparison of theoretical isochrones with observations. In this Letter, we use data from the SpeX instrument on the NASA Infrared Telescope Facility to measure the metallicity of the system during primary and secondary eclipses, as well as out of eclipse, based on an empirical metallicity calibration in the H and K near-infrared (NIR) bands. We derive an [Fe/H] = -0.30 {+-} 0.12 that is consistent across all orbital phases. The determination of [Fe/H] for this system constrains a key dimension of parameter space when attempting to reconcile model isochrone predictions and observations.

Terrien, Ryan C.; Fleming, Scott W.; Mahadevan, Suvrath; Deshpande, Rohit; Bender, Chad F.; Ramsey, Lawrence W. [Department of Astronomy and Astrophysics, The Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Feiden, Gregory A., E-mail: rct151@psu.edu [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH 03755 (United States)

2012-11-20

107

Ejs CM Lagrangian Pendulum Spring Model  

NSDL National Science Digital Library

The Lagrangian Pendulum Spring model asks students to solve the Lagrangian for a spring-pendulum and then develop a computational model of it. The model framework is distributed as a ready-to-run (compiled) Java archive. Double-clicking the ejs_CM_Lagrangian_pendulum_spring.jar file will run the program if Java is installed. In order to run correctly, the student must add the correct physics to the EJS differential equation solver and parameter definitions. If EJS is installed on your computer, you can right-click within the simulation window and select Open Ejs Model from the pop-up menu. Information about Ejs (Easy Java Simulations) is available at: http://www.um.es/fem/Ejs/. The CM Lagrangian Pendulum Spring model is one of several Easy Java Simulations (Ejs) models used to incorporate computational physics in Classical Mechanics. Ejs, a part of the Open Source Physics Project, is designed to make it easier to access, modify and generate computer models. Additional models can be found by searching ComPADRE for Ejs.

Cox, Anne

2008-06-04

108

The Metallicity of the CM Draconis System  

NASA Astrophysics Data System (ADS)

The CM Draconis system comprises two eclipsing mid-M dwarfs of nearly equal mass in a 1.27 day orbit. This well-studied eclipsing binary has often been used for benchmark tests of stellar models, since its components are among the lowest mass stars with well-measured masses and radii (lsim 1% relative precision). However, as with many other low-mass stars, non-magnetic models have been unable to match the observed radii and effective temperatures for CM Dra at the 5%-10% level. To date, the uncertain metallicity of the system has complicated comparison of theoretical isochrones with observations. In this Letter, we use data from the SpeX instrument on the NASA Infrared Telescope Facility to measure the metallicity of the system during primary and secondary eclipses, as well as out of eclipse, based on an empirical metallicity calibration in the H and K near-infrared (NIR) bands. We derive an [Fe/H] = -0.30 ± 0.12 that is consistent across all orbital phases. The determination of [Fe/H] for this system constrains a key dimension of parameter space when attempting to reconcile model isochrone predictions and observations.

Terrien, Ryan C.; Fleming, Scott W.; Mahadevan, Suvrath; Deshpande, Rohit; Feiden, Gregory A.; Bender, Chad F.; Ramsey, Lawrence W.

2012-11-01

109

The S=1 Underscreened Anderson Lattice model for Uranium compounds  

Microsoft Academic Search

Magnetic properties of uranium and neptunium compounds showing coexistence of the Kondo effect and ferromagnetic order are investigated within the degenerate Anderson Lattice Hamiltonian, describing a 5f2 electronic configuration with S = 1 spins. Through the Schrieffer-Wolff transformation, both an exchange Kondo interaction for the S = 1 f-spins and an effective f-band term are obtained, allowing to describe the

C. Thomas; A. S. R. Simões; J. R. Iglesias; C. Lacroix; N. B. Perkins; B. Coqblin

2011-01-01

110

Supersymmetric gauge theories on S4×S1  

NASA Astrophysics Data System (ADS)

We construct a supersymmetric gauge theory on S4×S1. We find a consistent supersymmetry transformation which reduces to the 4D N=2 supersymmetry transformation studied by Pestun by the dimensional reduction on S1. We find that there is no analogue of the usual Yang-Mills action except in the 4D limit. We also apply the localization technique to the partition function of the theories.

Terashima, Seiji

2014-06-01

111

Albumin modulates S1P delivery from red blood cells in perfused microvessels: mechanism of the protein effect.  

PubMed

Removal of plasma proteins from perfusates increases vascular permeability. The common interpretation of the action of albumin is that it forms part of the permeability barrier by electrostatic binding to the endothelial glycocalyx. We tested the alternate hypothesis that removal of perfusate albumin in rat venular microvessels decreased the availability of sphingosine-1-phosphate (S1P), which is normally carried in plasma bound to albumin and lipoproteins and is required to maintain stable baseline endothelial barriers (Am J Physiol Heart Circ Physiol 303: H825-H834, 2012). Red blood cells (RBCs) are a primary source of S1P in the normal circulation. We compared apparent albumin permeability coefficients [solute permeability (Ps)] measured using perfusates containing albumin (10 mg/ml, control) and conditioned by 20-min exposure to rat RBCs with Ps when test perfusates were in RBC-conditioned protein-free Ringer solution. The control perfusate S1P concentration (439 ± 46 nM) was near the normal plasma value at 37 °C and established a stable baseline Ps (0.9 ± 0.4 × 10(-6) cm/s). Ringer solution perfusate contained 52 ± 8 nM S1P and increased Ps more than 10-fold (16.1 ± 3.9 × 10(-6) cm/s). Consistent with albumin-dependent transport of S1P from RBCs, S1P concentrations in RBC-conditioned solutions decreased as albumin concentration, hematocrit, and temperature decreased. Protein-free Ringer solution perfusates that used liposomes instead of RBCs as flow markers failed to maintain normal permeability, reproducing the "albumin effect" in these mammalian microvessels. We conclude that the albumin effect depends on the action of albumin to facilitate the release and transport of S1P from RBCs that normally provide a significant amount of S1P to the endothelium. PMID:24531813

Adamson, R H; Clark, J F; Radeva, M; Kheirolomoom, A; Ferrara, K W; Curry, F E

2014-04-01

112

10?7 m 17?-oestradiol enhances odonto/osteogenic potency of human dental pulp stem cells by activation of the NF-?B pathway  

PubMed Central

Objectives Oestrogen has been proven to significantly enhance osteogenic potency, while oestrogen deficiency usually leads to impaired osteogenic differentiation of mesenchymal stem cells. However, little is known concerning direct effects of oestrogen on differentiation of human dental pulp stem cells (DPSCs). Materials and methods In this study, human DPSCs were isolated and treated with 10?7 m 17?-oestradiol (E2). Alkaline phosphatase (ALP) assay and alizarin red staining were performed. Results Alkaline phosphatase and alizarin red showed that E2 treatment significantly enhanced ALP activity and mineralization ability of DPSCs, but had no effect on cell proliferation. Real-time RT-PCR and western blot assay demonstrated that odonto/osteogenic markers (ALP, RUNX2/RUNX2, OSX/OSX, OCN/OCN and DSPP/DSP) were significantly upregulated in the cells after E2 treatment. Moreover, phosphorylation of cytoplasmic I?B?/P65 and expression of nuclear P65 were enhanced in a time-dependent manner following E2 treatment, suggesting activation of NF-?B signaling. Conversely, inhibition of the NF-?B pathway suppressed E2-mediated upregulation of odonto/osteogenic markers, indicating that the NF-?B pathway was pivotal for E2-mediated differentiation. Conclusion These findings provide evidence that 10?7 m 17?-oestradiol promoted odonto/osteogenic differentiation of human DPSCs via activation of the NF-?B signaling pathway.

Wang, Y; Zheng, Y; Wang, Z; Li, J; Wang, Z; Zhang, G; Yu, J

2013-01-01

113

77 FR 8877 - ICD-9-CM Coordination and Maintenance (C&M) Committee Meeting  

Federal Register 2010, 2011, 2012, 2013

...and http://www.cdc.gov/nchs/icd/icd9cm_maintenance.htm. Contact Persons for Additional Information: Donna Pickett, Medical Systems Administrator, Classifications and Public Health Data Standards Staff, NCHS, 3311 Toledo Road, Room...

2012-02-15

114

The 30-cm ion thruster power processor  

NASA Technical Reports Server (NTRS)

A power processor unit for powering and controlling the 30 cm Mercury Electron-Bombardment Ion Thruster was designed, fabricated, and tested. The unit uses a unique and highly efficient transistor bridge inverter power stage in its implementation. The system operated from a 200 to 400 V dc input power bus, provides 12 independently controllable and closely regulated dc power outputs, and has an overall power conditioning capacity of 3.5 kW. Protective circuitry was incorporated as an integral part of the design to assure failure-free operation during transient and steady-state load faults. The implemented unit demonstrated an electrical efficiency between 91.5 and 91.9 at its nominal rated load over the 200 to 400 V dc input bus range.

Herron, B. G.; Hopper, D. J.

1978-01-01

115

NASA 30 cm ion thruster development status  

NASA Technical Reports Server (NTRS)

A 30 cm diameter xenon ion thruster is under development at NASA to provide an ion propulsion option for missions of national interest and it is an element of the NASA Solar Electric Propulsion Technology Applications Readiness (NSTAR) program established to validate ion propulsion for space flight applications. The thruster has been developed to an engineering model level and it incorporates innovations in design, materials, and fabrication techniques compared to those employed to conventional ion thrusters. The performance of both functional and engineering model thrusters has been assessed including thrust stand measurements, over an input power range of 0.5-2.3 kW. Attributes of the engineering model thruster include an overall mass of 6.4 kg, and an efficiency of 65 percent and thrust of 93 mN at 2.3 kW input power. This paper discusses the design, performance, and lifetime expectations of the functional and engineering model thrusters under development at NASA.

Patterson, Michael J.; Haag, Thomas W.; Rawlin, Vincent K.; Kussmaul, Michael T.

1995-01-01

116

Investigation of spheromak configuration generated by inductive methods in the S-1 device  

SciTech Connect

This paper summarizes the characteristics of the spheromak plasmas obtained during the past five-year operation period of S-1 experiments. The S-1 Spheromak device, which began operation in 1983, generates a compact toroid in which the self-generated toroidal field in the plasma is comparable to the poloidal field. The S-1 experiment is unique in that spheromak plasmas are formed by inductive transfer of magnetic flux from a toroidal-shaped ''flux core,'' and plasma stability is maintained by shaping of the externally applied equilibrium field and using loose-fitting passive conductors. The most important objective for the S-1 experiment is to investigate the confinement feature of the spheromak configuration. With a rather extensive diagnostic system for this size device, the transport characteristics of the S-1 spheromak have been measured for plasmas with 10 /approx lt/ T/sub e/ less than or equal to 130 eV and 2 /approx lt/ n/sub e/ /approx lt/ 15 /times/ 10/sup 13/ cm/sup /minus/3/. The scaling of electron temperature T/sub e/ and density n/sub e/ with plasma current density has been obtained in a wide operation regime. The most important finding is that the peak electron pressure scales as n/sub eo/T/sub eo/ /proportional to/ j/sub o//sup 2/ (j/sub o/ = peak toroidal current density) with T/sub eo/ /proportinal to/ j/sub o//sup 2/ and n/sub eo/ approx. = constant. These scaling results, which are similar to those obtained in the reversed-field pinch device, suggest that ..beta.. = constant. Energy and particle confinement times are determined. 44 refs., 35 figs.

Yamada, M.; Janos, A.C.; Ellis, R.A. Jr.; Hart, G.W.; Levinton, F.M.; Mayo, R.M.; Meyerhofer, D.D.; Mimura, M.; Motley, R.W.; Ono, Y.; Paul, S.; Ueda, Y.

1988-08-01

117

Detecting the 21 cm forest in the 21 cm power spectrum  

NASA Astrophysics Data System (ADS)

We describe a new technique for constraining the radio-loud population of active galactic nuclei at high redshift by measuring the imprint of 21 cm spectral absorption features (the 21 cm forest) on the 21 cm power spectrum. Using semi-numerical simulations of the intergalactic medium and a semi-empirical source population, we show that the 21 cm forest dominates a distinctive region of k-space, k ? 0.5 Mpc- 1. By simulating foregrounds and noise for current and potential radio arrays, we find that a next-generation instrument with a collecting area of the order of ˜ 0.1 km2 (such as the Hydrogen Epoch of Reionization Array) may separately constrain the X-ray heating history at large spatial scales and radio-loud active galactic nuclei of the model we study at small ones. We extrapolate our detectability predictions for a single radio-loud active galactic nuclei population to arbitrary source scenarios by analytically relating the 21 cm forest power spectrum to the optical depth power spectrum and an integral over the radio luminosity function.

Ewall-Wice, Aaron; Dillon, Joshua S.; Mesinger, Andrei; Hewitt, Jacqueline

2014-07-01

118

Engineering model 8-cm thruster subsystem  

NASA Technical Reports Server (NTRS)

An Engineering Model (EM) 8 cm Ion Thruster Propulsion Subsystem was developed for operation at a thrust level 5 mN (1.1 mlb) at a specific impulse 1 sub sp = 2667 sec with a total system input power P sub in = 165 W. The system dry mass is 15 kg with a mercury-propellant-reservoir capacity of 8.75 kg permitting uninterrupted operation for about 12,500 hr. The subsystem can be started from a dormant condition in a time less than or equal to 15 min. The thruster has a design lifetime of 20,000 hr with 10,000 startup cycles. A gimbal unit is included to provide a thrust vector deflection capability of + or - 10 degrees in any direction from the zero position. The EM subsystem development program included thruster optimization, power-supply circuit optimization and flight packaging, subsystem integration, and subsystem acceptance testing including a cyclic test of the total propulsion package.

Herron, B. G.; Hyman, J.; Hopper, D. J.; Williamson, W. S.; Dulgeroff, C. R.; Collett, C. R.

1978-01-01

119

?-ray performance of a 1242 cm 3 LaCl 3:Ce scintillation spectrometer  

NASA Astrophysics Data System (ADS)

We present the results of ?-ray measurements on a large 4?×6? LaCl 3:Ce crystal, characterized using radioactive sources over the range 14-3220 keV. The response of the crystal was found to be largely linear over the upper 90% of its dynamic range—the deviations at lower energies can be attributed to the shortcomings of the photomultiplier tube (PMT) and is in fact a generic problem when using high-gain PMTs with lanthanum halide scintillators. At 662 keV, a measured energy resolution of 4.1% FWHM was recorded at room temperature. In comparison to earlier generations of LaCl 3 detectors, the internal background spectrum shows significantly less X-ray, ?, ?-ray and ? contamination. The integral background count rate in the energy region 20 keV-3 MeV was determined to be 1.8 cm -3 s -1, of which most (1.5 cm -3 s -1) can be attributed to the ? continuum from 138La and only ˜0.04 cm -3 s -1 to the ? complex from 227Ac and daughters. Using these data, we have determined the light output of ? particles relative to the equivalent energy electrons (or alternately ?-rays) to be, ?/ ?=0.35±0.02.

Owens, Alan; Bos, A. J. J.; Brandenburg, S.; Dathy, C.; Dorenbos, P.; Kraft, S.; Ostendorf, R. W.; Ouspenski, V.; Quarati, F.

2007-04-01

120

10.7 Gb/s electronic predistortion transmitter using commercial FPGAs and D/A converters implementing real-time DSP for chromatic dispersion and SPM compensation.  

PubMed

We present an experimental demonstration of simultaneous chromatic dispersion and self-phase modulation compensation at 10.7 Gb/s using real-time electronic digital signal processing. This was achieved using a pre-distorting transmitter based on commercially available field programmable gate arrays and 21.4 GS/s, 6-bit resolution digital-to-analog converters. The digital signal processing employed look-up tables stored in RAM. This resulted in the achievement of a BER of 10(-6) at an OSNR of 16 dB after transmission over a 450 km link of uncompensated standard single mode fiber with + 4 dBm launch power. PMID:19434196

Waegemans, Robert; Herbst, Stefan; Holbein, Ludwig; Watts, Philip; Bayvel, Polina; Fürst, Cornelius; Killey, Robert I

2009-05-11

121

A sub-cm micromachined electron microscope  

NASA Technical Reports Server (NTRS)

A new approach for fabricating macroscopic (approximately 10x10x10 mm(exp 3)) structures with micron accuracy has been developed. This approach combines the precision of semiconductor processing and fiber optic technologies. A (100) silicon wafer is anisotropically etched to create four orthogonal v-grooves and an aperture on each 10x12 mm die. Precision 308 micron optical fibers are sandwiched between the die to align the v-grooves. The fiber is then anodically bonded to the die above and below it. This procedure is repeated to create thick structures and a stack of 5 or 6 die will be used to create a miniature scanning electron microscope (MSEM). Two die in the structure will have a segmented electrode to deflect the beam and correct for astigmatism. The entire structure is UHV compatible. The performance of an SEM improves as its length is reduced and a sub-cm 2 keV MSEM with a field emission source should have approximately 1 nm resolution. A low voltage high resolution MSEM would be useful for the examination of biological specimens and semiconductors with a minimum of damage. The first MSEM will be tested with existing 6 micron thermionic sources. In the future a micromachined field emission source will be used. The stacking technology presented in this paper can produce an array of MSEMs 1 to 30 mm in length with a 1 mm or larger period. A key question being addressed by this research is the optimum size for a low voltage MSEM which will be determined by the required spatial resolution, field of view, and working distance.

Feinerman, A. D.; Crewe, D. A.; Perng, D. C.; Shoaf, S. E.; Crewe, A. V.

1993-01-01

122

The impending demise of comet C/2012 S1 (ISON)  

NASA Astrophysics Data System (ADS)

We present evidence to conclude that it is very probable that comet C/2012 S1 (ISON) will disintegrate before reaching perihelion. Figs. 1 and 7 of this work are particularly revealing. The comet is following the path of disintegrating comets and not the path of normal Oort Cloud comets, suggesting that C/2012 S1 (ISON) is going to disintegrate. Note: the comet disintegrated on November 13th, according to this prediction while this paper was being refereed (CBET 3731). We present evidence to conclude that it is very probable that comet C/2012 S1 (ISON) will disintegrate before reaching perihelion. Some Oort Cloud comets exhibit a signature (a slope discontinuity event (SDE)+a magnitude dip after the event) that has predictive power. Figs. 1 and 7 of this work are particularly revealing. The comet is following the path of disintegrating comets and not the path of normal Oort Cloud comets, suggesting that C/2012 S1(ISON) is going to disintegrate. Note: the comet disintegrated on November 13th while this paper was being refereed (CBET 3731).

Ferrín, Ignacio

2014-06-01

123

Yang-Mills solutions in S3 × S1  

Microsoft Academic Search

A search is conducted for new solutions to Yang–Mills classical field theory defined on S3×S1 using Witten’s ansatz. Then some sort of non-Abelian plane waves giving rise to a divergent energy are obtained.

Javier Villarroel

1987-01-01

124

Development of an imaging microstrip gas chamber with a 5 cm × 5 cm area based on multi-chip module technology  

NASA Astrophysics Data System (ADS)

We have developed a two-dimensional MicroStrip Gas Chamber (MSGC) with a 5 cm × 5 cm detection area based on Multi-Chip Module (MCM) technology. It has a 17 ?m thin substrate, 254 anodes, and 255 back strips both with a 200 ?m pitch. The MSGC was mounted on a large Pin Grid Array (PGA) package having more than 500 pins, which allowed us to readily connect a large number of signals of an imaging MSGC with readout electronics. In this article, we report on the capability of the MSGC as an X-ray imaging detector operated near an intense X-ray source. In order to get stable operation at high X-ray intensity, we found one solution using a ˜ 20 ?m substrate and a surface resistivity of ˜ 10 15 ?/square. The control of the surface resistivity was carried out by coating the polyimide substrate with organic titanium. This improvement enabled the MSGC to be stably operated for ˜ 10 3 s under a very high counting rate of 10 7 Hz/mm 2. The MSGC is also being operated for several months under medium intensity X-rays from an X-ray generator. In this measurement, high quality digital X-ray images with ˜ 60 ?m RMS (Root Mean Square) position resolution were obtained with a simple-readout method of recording only the positions of hit electrodes.

Tanimori, Toru; Ochi, Atsuhiko; Minami, Seiji; Nagae, Tomofumi

1996-02-01

125

Reduced dimension rovibrational variational calculations of the S1 state of C2H2. II. The S1 rovibrational manifold and the effects of isomerization  

NASA Astrophysics Data System (ADS)

Reduced dimension variational calculations have been performed for the rovibrational level structure of the S1 state of acetylene. The state exhibits an unusually complicated level structure, for various reasons. First, the potential energy surface has two accessible conformers, trans and cis. The cis conformer lies about 2700 cm-1 above the trans, and the barrier to cis-trans isomerization lies about 5000 cm-1 above the trans minimum. The trans vibrations ?4 (torsion) and ?6 (asym. bend) interact very strongly by Darling-Dennison and Coriolis resonances, such that their combination levels and overtones form polyads with unexpected structures. Both conformers exhibit very large x36 cross-anharmonicity since the pathway to isomerization is a combination of ?6 and ?3 (sym. bend). Near the isomerization barrier, the vibrational levels show an even-odd K-staggering of their rotational levels as a result of quantum mechanical tunneling through the barrier. The present calculations address all of these complications, and reproduce the observed K-structures of the bending and C-C stretching levels with good qualitative accuracy. It is expected that they will assist with the assignment of the irregular patterns near the isomerization barrier.

Changala, P. Bryan; Baraban, Joshua H.; Stanton, John F.; Merer, Anthony J.; Field, Robert W.

2014-01-01

126

Reduced dimension rovibrational variational calculations of the S(1) state of C2H2. II. The S(1) rovibrational manifold and the effects of isomerization.  

PubMed

Reduced dimension variational calculations have been performed for the rovibrational level structure of the S1 state of acetylene. The state exhibits an unusually complicated level structure, for various reasons. First, the potential energy surface has two accessible conformers, trans and cis. The cis conformer lies about 2700 cm(-1) above the trans, and the barrier to cis-trans isomerization lies about 5000 cm(-1) above the trans minimum. The trans vibrations ?4 (torsion) and ?6 (asym. bend) interact very strongly by Darling-Dennison and Coriolis resonances, such that their combination levels and overtones form polyads with unexpected structures. Both conformers exhibit very large x36 cross-anharmonicity since the pathway to isomerization is a combination of ?6 and ?3 (sym. bend). Near the isomerization barrier, the vibrational levels show an even-odd K-staggering of their rotational levels as a result of quantum mechanical tunneling through the barrier. The present calculations address all of these complications, and reproduce the observed K-structures of the bending and C-C stretching levels with good qualitative accuracy. It is expected that they will assist with the assignment of the irregular patterns near the isomerization barrier. PMID:24437883

Changala, P Bryan; Baraban, Joshua H; Stanton, John F; Merer, Anthony J; Field, Robert W

2014-01-14

127

The Signatures of Particle Decay in 21 cm Absorption from the First Minihalos  

NASA Astrophysics Data System (ADS)

The imprint of decaying dark matter (DM) particles on the characteristics of the "21 cm forest"—absorption at 21 cm from minihalos in the spectra of distant radio-loud sources—is considered within a one-dimensional, self-consistent hydrodynamic description of minihalos from their turnaround point to virialization. The most pronounced influence of decaying DM on the evolution of minihalos is found in the mass range M = 105-106 M ?, for which unstable DM with a current upper limit on its ionization rate of ? L = 0.59 × 10-25 s-1 reduces the 21 cm optical depth by an order of magnitude compared with the standard recombination scenario. Even a rather modest ionization, ? ~ 0.3? L , practically erases absorption features and results in a considerable decrease (by factor of more than 2.5) of the number of strong (W_\

Vasiliev, Evgenii O.; Shchekinov, Yuri A.

2013-11-01

128

S1(n, ??), 1A2 fluorescence and T1(n, ??), 3A2 phosphorescence spectra of xanthone vapor  

NASA Astrophysics Data System (ADS)

Emission spectra of xanthone vapor have been measured at different temperatures along with the excitation and absorption spectra. Fluorescence from the S1(n, ??), 1A2 and phosphorescence from the T1(n, ??), 3A2 states were separated to extract only the fluorescence spectrum. The vibrational structure of the fluorescence was interpreted in terms of the Cdbnd O stretching mode and the modes combined with the Cdbnd O stretching, showing a maximum near 24 000 cm-1. The locations of the S1 and T1 origins are observed at 26 940 and 25 700 cm-1, respectively. Analysis of the data includes the determination of the vibrational frequencies in the fluorescence and phosphorescence.

Itoh, Takao

2014-04-01

129

STS-112 S1 Truss Payload arrives at KSC  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- Inside the Operations and Checkout Building, a strongback lifts the S1 truss from the Guppy cargo carrier that protected it during flight and transfer. Manufactured by the Boeing Co. in Huntington Beach, Calif., this component of the International Space Station is the first starboard (right-side) truss segment, whose main job is providing structural support for the orbiting research facility's radiator panels that cool the Space Station's complex power system. The S1 truss se gment also will house communications systems, external experiment positions and other subsystems. Primarily constructed of aluminum, the truss segment is 45 feet long, 15 feet wide and 6 feet tall. When fully outfitted, it will weigh 31,137 pounds. The tr uss is slated for flight in 2001

1999-01-01

130

STS-112 S1 Truss Payload arrives at KSC  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- A KSC transporter moves the Guppy cargo carrier encasing the S1 truss into the Operations and Checkout Building. Manufactured by the Boeing Co. in Huntington Beach, Calif., this component of the International Space Station is the first starboard (right-side) truss segment, whose main job is providing structural support for the orbiting research facility's radiator panels that cool the Space Station's complex power system. The S1 truss segment also will house communications systems, external experiment positions and other subsystems. Primarily constructed of aluminum, the truss segment is 45 feet long, 15 feet wide and 6 feet tall. When fully outfitted, it will weigh 31,137 pounds. The truss is slated for flight in 2001.

1999-01-01

131

STS-112 S1 Truss Payload arrives at KSC  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- Inside the Operations and Checkout Building, a strongback is lowered toward the S1 truss below it in order to lift the truss from the Guppy cargo carrier that protected it during flight and transfer. Manufactured by the Boeing Co. in Huntington Beach, Calif., this component of the International Space Station is the first starboard (right-side) truss segment, whose main job is providing structural support for the orbiting research facility's radiator panels that cool the Space Station's complex power system. The S1 truss segment also will house communications systems, external experiment positions and other subsystems. Primarily constructed of aluminum, the truss segment is 45 feet long, 15 feet wide and 6 feet tall. When full y outfitted, it will weigh 31,137 pounds. The truss is slated for flight in 2001

1999-01-01

132

STS-112 S1 Truss Payload arrives at KSC  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- Inside the Operations and Checkout Building, the top of the Guppy cargo carrier is lifted off the S1 truss (background). Manufactured by the Boeing Co. in Huntington Beach, Calif., this component of the International Space Station is the first starboard (right-side) truss segment, whose main job is providing structural support for the orbiting research facility's radiator panels that cool the Space Station's complex power system. The S1 truss segment also will house communica tions systems, external experiment positions and other subsystems. Primarily constructed of aluminum, the truss segment is 45 feet long, 15 feet wide and 6 feet tall. When fully outfitted, it will weigh 31,137 pounds. The truss is slated for flight in 200 1

1999-01-01

133

Association between Prenatal Exposure to Methylmercury and Visuospatial Ability at 10.7 years in the Seychelles Child Development Study1  

PubMed Central

The Seychelles Child Development Study was designed to test the hypothesis that prenatal exposure to MeHg from maternal consumption of a diet high in fish is detrimental to child neurodevelopment. To date, no consistent pattern of adverse associations between prenatal exposure and children’s development has appeared. In a comprehensive review of developmental studies involving MeHg, a panel of experts recommended a more consistent use of the same endpoints across studies to facilitate comparisons. Both the SCDS and the Faeroe Islands studies administered the Bender Visual Motor Gestalt Test. However, the method of test administration and scoring used was different. We repeated the test on the SCDS Main Study children (mean age 10.7 years) using the same testing and scoring procedure reported by the Faeroe studies to obtain Copying Task and Reproduction Task scores. We found no association between prenatal MeHg exposure and Copying Task scores which was reported from the Faeroese study. However, our analysis did show a significant adverse association between MeHg and Reproduction Task scores with all the data (p= 0.04), but not when the single outlier was removed (p = 0.07). In a population whose exposure to MeHg is from fish consumption, we continue to find no consistent adverse association between MeHg and visual motor coordination.

Davidson, Philip W.; Jean-Sloane-Reeves; Myers, Gary J.; Hansen, Ole N?rby; Huang, Li-Shan; Georger, Leslie A.; Cox, Christopher; Thurston, Sally W.; Shamlaye, Conrad F.; Clarkson, Thomas W.

2008-01-01

134

Raman scattering for the Heisenberg S=1\\/2 antiferromagnet  

Microsoft Academic Search

We study the full Raman intensity for the Heisenberg S=1\\/2 antiferromagnet on the triangular lattice by simultaneously considering the effects of the renormalization of the spectrum by 1\\/S corrections, and the final state magnon-magnon interactions. The analysis of the Raman intensity without final state interactions shows, that it has two peaks, corresponding to two maxima of the bare magnon spectrum

Natalia Perkins; Wolfram Brenig

2008-01-01

135

Osmo-, Thermo- and Ethanol- Tolerances of Saccharomyces cerevisiae S1  

PubMed Central

Saccharomyces cerevisiae S1, which is a locally isolated and improved strain showed viability at 40, 45 and 50°C and produced ethanol at 40, 43 and 45°C. When the cells were given heat shock at 45°C for 30min and grown at 40°C, 100% viability was observed for 60h, and addition of 200gL?1 ethanol has led to complete cell death at 30h. Heat shock given at 45°C (for 30min) has improved the tolerance to temperature induced ethanol shock leading to 37% viability at 30h. When the cells were subjected to ethanol (200gL?1 for 30 min) and osmotic shock (sorbitol 300gL?1), trehalose contents in the cells were increased. The heat shocked cells showed better viability in presence of added ethanol. Soy flour supplementation has improved the viability of S. cerevisiae S1 to 80% in presence of 100gL?1 added ethanol and to 60% in presence of 300gL?1sorbitol. In presence of sorbitol (200gL?1) and ethanol (50gL?1) at 40°C, 46% viability was retained by S. cerevisiae S1 at 48h and it was improved to 80% by soy flour supplementation.

Balakumar, Sandrasegarampillai; Arasaratnam, Vasanthy

2012-01-01

136

Sphingosine 1-phosphate (S1P)/S1P receptor 1 signaling regulates receptor activator of NF-?B ligand (RANKL) expression in rheumatoid arthritis  

PubMed Central

Sphingosine 1-phosphate (S1P)/S1P receptor 1 (S1P1) signaling plays an important role in synovial cell proliferation and inflammatory gene expression by rheumatoid arthritis (RA) synoviocytes. The purpose of this study is to clarify the role of S1P/S1P1 signaling in the expression of receptor activator of NF-?B ligand (RANKL) in RA synoviocytes and CD4+ T cells. We demonstrated MH7A cells, a human RA synovial cell line, and CD4+ T cells expressed S1P1 and RANKL. Surprisingly, S1P increased RANKL expression in MH7A cells and CD4+ T cells in a dose-dependent manner. Moreover, S1P enhanced RANKL expression induced by stimulation with TNF-? in MH7A cells and CD4+ T cells. These effects of S1P in MH7A cells were inhibited by pretreatment with PTX, a specific Gi/Go inhibitor. These findings suggest that S1P/S1P1 signaling may play an important role in RANKL expression by MH7A cells and CD4+ T cells. S1P/S1P1 signaling of RA synoviocytes is closely connected with synovial hyperplasia, inflammation, and RANKL-induced osteoclastogenesis in RA. Thus, regulation of S1P/S1P1 signaling may become a novel therapeutic target for RA.

Takeshita, Harunori; Kitano, Masayasu; Iwasaki, Tsuyoshi; Kitano, Sachie; Tsunemi, Sachi; Sato, Chieri; Sekiguchi, Masahiro; Azuma, Naoto; Miyazawa, Keiji; Hla, Timothy; Sano, Hajime

2013-01-01

137

Limited (L4-S1, L5-S1) Selective Dorsal Rhizotomy for Reducing Spasticity in Cerebral Palsy  

Microsoft Academic Search

Summary  ?Selective posterior rhizotomy is effective for relieving spasticity associated with cerebral palsy. In current techniques\\u000a dorsal roots from L1\\/L2 to S1\\/S2 are selectively divided. With transoperative electromyography (EMG) significant sensory loss\\u000a has been prevented, but postoperative hypotonia following excessive reduction of the fusimotor drive is still of concern for\\u000a surgeons and therapists. To decrease the volume of deafferentiated rootlets we

J. A. Lazareff; M. A. Garcia-Mendez; R. De Rosa; Charles Olmstead

1999-01-01

138

Collisional facilitation of aqueous alteration of CM and CV carbonaceous chondrites  

NASA Astrophysics Data System (ADS)

CM chondrites exhibit a strong correlation between the degree of alteration and the extent of particle alignment (i.e., the strength of the petrofabric). It seems likely that the S1 shock stage of essentially every CM and the high matrix abundance (˜70 vol.%) of these samples ensured that the shock waves that produced CM petrofabrics (by collapsing matrix pores and squeezing chondrules into pore spaces) were significantly attenuated and were too weak to damage olivine crystal lattices. Random collisions on the CM body produced petrofabrics and created fractures in the target rocks. Subsequent impact-mobilization of water caused hydrated phases to form preferentially in the more-fractured regions (those with the strongest petrofabrics); the less-deformed, less-fractured CM regions experienced lower degrees of aqueous alteration. Many CV3 chondrites also have petrofabrics: roughly half are from the oxidized Bali-like subgroup (CV3OxB), roughly half are from the reduced subgroup (CV3R) and none is from the oxidized Allende-like subgroup (CV3OxA) (which is less altered than CV3OxB). Nearly all CVs with petrofabrics are S3-S4 and nearly all CVs that lack petrofabrics are S1. Oxidized CVs have much higher porosities (typically 20-28%) than reduced CVs (0.6-8%), facilitating more-extensive aqueous alteration. The CV3R chondrites formed from low-porosity material that inhibited oxidation during alteration. The oxidized CV subgroups formed from higher-porosity materials. The CV3OxB samples were shocked, became extensively fractured and developed petrofabrics; the CV3OxA samples were not shocked and never developed petrofabrics. When water was mobilized, both sets of porous CV chondrites became oxidized; the more-fractured CV3OxB subgroup was more severely altered.

Rubin, Alan E.

2012-08-01

139

Infrared Spectroscopy of Comet C/2012 S1 (ISON)  

NASA Astrophysics Data System (ADS)

Comet C/2012 S1 (ISON) provided a rare opportunity to study the dust characteristics of a dynamically new comet on a sungrazing orbit. Entering the inner solar system for the very first time, its surface layers have experienced little processing from solar irradiation. Its expected close passage of the Sun should remove a substantial amount of surface material, revealing the inner material stored for billions of years inside the nucleus. Here we present infrared spectroscopy of ISON, obtained with NASA’s Infrared Telescope Facility. This work was supported in part by the IR&D program at The Aerospace Corporation.

Sitko, Michael L.; Russell, R. W.; Yanamandra-Fisher, P. A.; Lisse, C. M.; Kelley, M. S.; Wooden, D. H.; Woodward, C. E.; Harker, D. E.; Grady, C.

2014-01-01

140

Local carbon diffusion coefficient measurement in the S-1 spheromak  

SciTech Connect

The local carbon diffusion coefficient was measured in the S - 1 spheromak by detecting the radial spread of injected carbon impurity. The radial impurity density profile is determined by the balance of ionization and diffusion. Using measured local electron temperature T/sub e/ and density n/sub e/, the ionization rate is determined from which the particle diffusion coefficient is inferred. The results found in this work are consistent with Bohm diffusion. The absolute magnitude of D/sub /perpendicular// was determined to be (4/approximately/6) /times/ D/sub Bohm/. 25 refs., 13 figs., 2 tabs.

Mayo, R.M.; Levinton, F.M.; Meyerhofer, D.D.; Chu, T.K.; Paul, S.F.; Yamada, M.

1988-10-01

141

Sphingosine 1-phosphate (S1P)/S1P receptor 1 signaling regulates receptor activator of NF-{kappa}B ligand (RANKL) expression in rheumatoid arthritis  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer MH7A cells and CD4{sup +} T cells expressed S1P1 and RANKL. Black-Right-Pointing-Pointer S1P increased RANKL expression in MH7A cells and CD4{sup +} T cells. Black-Right-Pointing-Pointer The effect of S1P in MH7A cells was inhibited by specific Gi/Go inhibitors. -- Abstract: Sphingosine 1-phosphate (S1P)/S1P receptor 1 (S1P1) signaling plays an important role in synovial cell proliferation and inflammatory gene expression by rheumatoid arthritis (RA) synoviocytes. The purpose of this study is to clarify the role of S1P/S1P1 signaling in the expression of receptor activator of NF-{kappa}B ligand (RANKL) in RA synoviocytes and CD4{sup +} T cells. We demonstrated MH7A cells, a human RA synovial cell line, and CD4{sup +} T cells expressed S1P1 and RANKL. Surprisingly, S1P increased RANKL expression in MH7A cells and CD4{sup +} T cells in a dose-dependent manner. Moreover, S1P enhanced RANKL expression induced by stimulation with TNF-{alpha} in MH7A cells and CD4{sup +} T cells. These effects of S1P in MH7A cells were inhibited by pretreatment with PTX, a specific Gi/Go inhibitor. These findings suggest that S1P/S1P1 signaling may play an important role in RANKL expression by MH7A cells and CD4{sup +} T cells. S1P/S1P1 signaling of RA synoviocytes is closely connected with synovial hyperplasia, inflammation, and RANKL-induced osteoclastogenesis in RA. Thus, regulation of S1P/S1P1 signaling may become a novel therapeutic target for RA.

Takeshita, Harunori [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan)] [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan); Kitano, Masayasu, E-mail: mkitano6@hyo-med.ac.jp [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan)] [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan); Iwasaki, Tsuyoshi [Department of Pharmacy, Hyogo University of Health Sciences, 1-3-6 Minatojima Kobe, Hyogo 650-8530 (Japan)] [Department of Pharmacy, Hyogo University of Health Sciences, 1-3-6 Minatojima Kobe, Hyogo 650-8530 (Japan); Kitano, Sachie; Tsunemi, Sachi; Sato, Chieri; Sekiguchi, Masahiro; Azuma, Naoto [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan)] [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan); Miyazawa, Keiji [Discovery Research III, Research and Development, Kissei Pharmaceutical Company, 4365-1 Hodakakashiwara, Azumino, Nagano 399-8304 (Japan)] [Discovery Research III, Research and Development, Kissei Pharmaceutical Company, 4365-1 Hodakakashiwara, Azumino, Nagano 399-8304 (Japan); Hla, Timothy [Center for Vascular Biology, Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, 1300 York Avenue, Box 69, NY 10065 (United States)] [Center for Vascular Biology, Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, 1300 York Avenue, Box 69, NY 10065 (United States); Sano, Hajime [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan)] [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan)

2012-03-09

142

Dissecting the hematopoietic microenvironment. II. The kinetics of the erythron of the S1/S1d mouse and the dual nature of its anemia.  

PubMed

An analysis of the S1/S1d mouse for ferrokinetics and fate of peripheral red blood cells has shown the cause of its anemia to be dual in nature. While the S1/S1d produces red cells at a slightly greater rate than its normal littermate, its bone marrow and spleen appear to be operating near their maximal capacity and will reduce their output if anemic stress is partly relieved. The cause of the moderately high level of erythropoiesis in the S1/S1d is a mean daily loss of 2.5--3.0% of its total blood volume via the intestinal tract. PMID:688326

Wolf, N S

1978-07-01

143

Reverse bias voltage testing of 8 cm x 8cm silicon solar cells  

NASA Technical Reports Server (NTRS)

A study is described of the reverse I-V characteristics of the largest space qualified silicon solar cells currently available (8 x 8 cm) and of reverse bias voltage (RBV) testing performed on these cells. This study includes production grade cells, both with and without cover glass. These cells span the typical output range seen in production. Initial characteristics of these cells are measured at both 28 and 60 C. These measurements show weak correlation between cell output and reverse characteristics. Analysis is presented to determine the proper conditions for RBV stress to simulate shadowing effects on a particular array design. After performing the RBV stress the characteristics of the stressed cells are remeasured. The degradation in cell performance is highly variable which exacerbates cell mismatching over time. The effect of this degradation on array lifetime is also discussed. Generalization of these results to other array configurations is also presented.

Woike, T.; Stotlar, S.; Lungu, C.

1991-01-01

144

Chrysanthemum CmNAR2 interacts with CmNRT2 in the control of nitrate uptake.  

PubMed

Nitrate transporters are an important component of plant growth and development. Chrysanthemum morifolium is an important ornamental species, for which a sufficient supply of nitrogenous fertilizer is required to maintain economic yields. In this study, the full-length cDNA of the nitrate transporter genes CmNRT2 and CmNAR2 were isolated. CmNRT2 transcript accumulation was inducible by both nitrate and ammonium, but the latter ion down-regulated the transcript accumulation of CmNAR2. CmNRT2 might be a plasma membrane localized protein, while CmNAR2 was distributed throughout the cell. CmNAR2 was shown to interact with CmNRT2 by in vitro and in vivo assays. Arabidopsis thaliana plants heterologously expressing CmNRT2 showed an increased rate of nitrate influx, while this trait was unaltered in plants expressing CmNAR2. Double transformants (CmNRT2 plus CmNAR2) exhibited an enhanced rate of nitrate influx into the root. Our data indicated that the interaction of CmNAR2 with CmNRT2 contributed to the uptake of nitrate. PMID:25060485

Gu, Chunsun; Zhang, Xiaoxue; Jiang, Jiafu; Guan, Zhiyong; Zhao, Shuang; Fang, Weimin; Liao, Yuan; Chen, Sumei; Chen, Fadi

2014-01-01

145

Intramolecular vibrational dynamics in S1 p-fluorotoluene. I. Direct observation of doorway states.  

PubMed

Picosecond time-resolved photoelectron spectroscopy is used to investigate intramolecular vibrational redistribution (IVR) following excitation of S(1) 18a(1) in p-fluorotoluene (pFT) at an internal energy of 845 cm(-1), where ?(18a) is a ring bending vibrational mode. Characteristic oscillations with periods of 8 ps and 5 ps are observed in the photoelectron signal and attributed to coupling between the initially excited zero-order bright state and two doorway states. Values for the coupling coefficients connecting these three vibrational states have been determined. In addition, an exponential change in photoelectron signal with a lifetime of 17 ps is attributed to weaker couplings with a bath of dark states that play a more significant role during the latter stages of IVR. A tier model has been used to assign the most strongly coupled doorway state to S(1) 17a(1) 6a(2)('), where ?(17a) is a CH out-of-plane vibrational mode and 6a(2)(') is a methyl torsional level. This assignment signifies that a torsion-vibration coupling mechanism mediates the observed dynamics, thus demonstrating the important role played by the methyl torsional mode in accelerating IVR. PMID:21974520

Davies, Julia A; Reid, Katharine L

2011-09-28

146

The fluorobenzene-argon S(1) excited-state intermolecular potential energy surface.  

PubMed

We evaluate the first excited-state (S1) intermolecular potential energy surface for the fluorobenzene-Ar van der Waals complex using the coupled cluster method and the augmented correlation-consistent polarized valence double-zeta basis set extended with a set of 3s3p2d1f1g midbond functions. To calculate the S(1) interaction energies, we use ground-state interaction energies evaluated with the same basis set and the coupled cluster singles and doubles (CCSD) including connected triple excitations [CCSD(T)] model and interaction and excitation energies evaluated at the CCSD level. The surface minima are characterized by the Ar atom located above and below the fluorobenzene ring at a distance of 3.5060 A with respect to the fluorobenzene center of mass and at an angle of 5.89 degrees with respect to the axis perpendicular to the fluorobenzene plane. The corresponding interaction energy is -425.226 cm(-1). The surface is used in the evaluation of the intermolecular level structure of the complex, and the results are compared to the experimental data available and to those found in previous theoretical papers on ground-state potentials for similar complexes. PMID:17658771

Fajín, José Luis Cagide; Capelo, Silvia Bouzón; Fernandez, Berta; Felker, Peter M

2007-08-16

147

Intramolecular vibrational dynamics in S1 p-fluorotoluene. I. Direct observation of doorway states  

NASA Astrophysics Data System (ADS)

Picosecond time-resolved photoelectron spectroscopy is used to investigate intramolecular vibrational redistribution (IVR) following excitation of S1 18a1 in p-fluorotoluene (pFT) at an internal energy of 845 cm-1, where ?18a is a ring bending vibrational mode. Characteristic oscillations with periods of 8 ps and 5 ps are observed in the photoelectron signal and attributed to coupling between the initially excited zero-order bright state and two doorway states. Values for the coupling coefficients connecting these three vibrational states have been determined. In addition, an exponential change in photoelectron signal with a lifetime of 17 ps is attributed to weaker couplings with a bath of dark states that play a more significant role during the latter stages of IVR. A tier model has been used to assign the most strongly coupled doorway state to S1 17a1 6a2', where ?17a is a CH out-of-plane vibrational mode and 6a2' is a methyl torsional level. This assignment signifies that a torsion-vibration coupling mechanism mediates the observed dynamics, thus demonstrating the important role played by the methyl torsional mode in accelerating IVR.

Davies, Julia A.; Reid, Katharine L.

2011-09-01

148

Complete genome sequence of Rhodospirillum rubrum type strain (S1).  

PubMed

Rhodospirillum rubrum (Esmarch 1887) Molisch 1907 is the type species of the genus Rhodospirillum, which is the type genus of the family Rhodospirillaceae in the class Alphaproteobacteria. The species is of special interest because it is an anoxygenic phototroph that produces extracellular elemental sulfur (instead of oxygen) while harvesting light. It contains one of the most simple photosynthetic systems currently known, lacking light harvesting complex 2. Strain S1(T) can grow on carbon monoxide as sole energy source. With currently over 1,750 PubMed entries, R. rubrum is one of the most intensively studied microbial species, in particular for physiological and genetic studies. Next to R. centenum strain SW, the genome sequence of strain S1(T) is only the second genome of a member of the genus Rhodospirillum to be published, but the first type strain genome from the genus. The 4,352,825 bp long chromosome and 53,732 bp plasmid with a total of 3,850 protein-coding and 83 RNA genes were sequenced as part of the DOE Joint Genome Institute Program DOEM 2002. PMID:21886856

Munk, A Christine; Copeland, Alex; Lucas, Susan; Lapidus, Alla; Del Rio, Tijana Glavina; Barry, Kerrie; Detter, John C; Hammon, Nancy; Israni, Sanjay; Pitluck, Sam; Brettin, Thomas; Bruce, David; Han, Cliff; Tapia, Roxanne; Gilna, Paul; Schmutz, Jeremy; Larimer, Frank; Land, Miriam; Kyrpides, Nikos C; Mavromatis, Konstantinos; Richardson, Paul; Rohde, Manfred; Göker, Markus; Klenk, Hans-Peter; Zhang, Yaoping; Roberts, Gary P; Reslewic, Susan; Schwartz, David C

2011-07-01

149

STS-112 S1 Truss Payload arrives at KSC  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- At the Shuttle Landing Facility, the newly arrived S1 truss, a segment of the International Space Station (ISS), is offloaded from NASA's Super Guppy aircraft. Manufactured by the Boeing Co. in Huntington Beach, Calif., this component of the ISS is the first starboard (right-side) truss segment, whose main job is providing structural support for the orbiting research facility's radiator panels that cool the Space Station's complex power system. The S1 truss segment also will house communications systems, external experiment positions and other subsystems. Primarily constructed of aluminum, the truss segment is 45 feet long, 15 feet wide and 6 feet tall. When fully outfitted, it will weigh 31,137 pounds. The truss is slated fo r flight in 2001. The Super Guppy, with its 25-foot diameter fuselage designed to handle oversized loads, is well prepared to transport the truss and other ISS segments. Loading the Guppy is easy because of the unique 'fold-away' nose of the aircraft that opens 110 degrees for cargo loading. A system of rails in the cargo compartment, used with either Guppy pallets or fixtures designed for specific cargo, makes cargo loading simple and efficient. Rollers mounted in the rails allow pallets or fixtures to b e moved by an electric winch mounted beneath the cargo floor. Automatic hydraulic lock pins in each rail secure the pallet for flight. The truss is being transferred to the Operations and Checkout Building.

1999-01-01

150

STS-112 S1 Truss Payload arrives at KSC  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- At the Shuttle Landing Facility, workers attach cranes to the S1 truss, a segment of the International Space Station, to lift the truss to a payload transporter for its transfer to the Operations and Checkout Building. Manufa ctured by the Boeing Co. in Huntington Beach, Calif., this component of the ISS is the first starboard (right-side) truss segment, whose main job is providing structural support for the orbiting research facility's radiator panels that cool the Space Station's complex power system. The S1 truss segment also will house communications systems, external experiment positions and other subsystems. Primarily constructed of aluminum, the truss segment is 45 feet long, 15 feet wide and 6 feet tall. When fully out fitted, it will weigh 31,137 pounds. The truss is slated for flight in 2001. The truss arrived at KSC aboard NASA's Super Guppy, with a 25-foot diameter fuselage designed to handle oversized loads. Loading the Guppy is easy because of the unique 'fold-away' nose of the aircraft that opens 110 degrees for cargo loading. A system of rails in the cargo compartment, used with either Guppy pallets or fixtures designed for specific cargo, makes cargo loading simple and efficient. Rollers mounted in the rails al low pallets or fixtures to be moved by an electric winch mounted beneath the cargo floor. Automatic hydraulic lock pins in each rail secure the pallet for flight

1999-01-01

151

STS-112 S1 Truss Payload arrives at KSC  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- At KSC's Shuttle Landing Facility, NASA's Super Guppy opens to reveal its cargo, the International Space Station's (ISS) S1 truss. Manufactured by the Boeing Co. in Huntington Beach, Calif., this component of the ISS is the f irst starboard (right-side) truss segment, whose main job is providing structural support for the orbiting research facility's radiator panels that cool the Space Station's complex power system. The S1 truss segment also will house communications systems, external experiment positions and other subsystems. Primarily constructed of aluminum, the truss segment is 45 feet long, 15 feet wide and 6 feet tall. When fully outfitted, it will weigh 31,137 pounds. The truss is slated for flight in 2001. The Super G uppy, with its 25-foot diameter fuselage designed to handle oversized loads, is well prepared to transport the truss and other ISS segments. Loading the Guppy is easy because of the unique 'fold-away' nose of the aircraft that opens 110 degrees for cargo loading. A system of rails in the cargo compartment, used with either Guppy pallets or fixtures designed for specific cargo, makes cargo loading simple and efficient. Rollers mounted in the rails allow pallets or fixtures to be moved by an electric winch mounted beneath the cargo floor. Automatic hydraulic lock pins in each rail secure the pallet for flight. The truss is to be transferred to the Operations and Checkout Building

1999-01-01

152

STS-112 S1 Truss Payload arrives at KSC  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- At the Shuttle Landing Facility, the S1 truss, a segment of the International Space Station, is moved away from the Super Guppy that brought it to KSC from Marshall Space Flight Center. Manufactured by the Boeing Co. in Hunti ngton Beach, Calif., this component of the ISS is the first starboard (right-side) truss segment, whose main job is providing structural support for the orbiting research facility's radiator panels that cool the Space Station's complex power system. The S 1 truss segment also will house communications systems, external experiment positions and other subsystems. Primarily constructed of aluminum, the truss segment is 45 feet long, 15 feet wide and 6 feet tall. When fully outfitted, it will weigh 31,137 poun ds. The truss is slated for flight in 2001. The Super Guppy, with its 25-foot diameter fuselage designed to handle oversized loads, is well prepared to transport the truss and other ISS segments. Loading the Guppy is easy because of the unique 'fold-away' nose of the aircraft that opens 110 degrees for cargo loading. A system of rails in the cargo compartment, used with either Guppy pallets or fixtures designed for specific cargo, makes cargo loading simple and efficient. Rollers mounted in the rails allow pallets or fixtures to be moved by an electric winch mounted beneath the cargo floor. Automatic hydraulic lock pins in each rail secure the pallet for flight. The truss is being transferred to the Operations and Checkout Building.

1999-01-01

153

STS-112 S1 Truss Payload arrives at KSC  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- Escort vehicles prepare to leave the Shuttle Landing Facility with the S1 truss (at right) on its trek to the Operations and Checkout Building. Manufactured by the Boeing Co. in Huntington Beach, Calif., this component of the ISS is the first starboard (right-side) truss segment, whose main job is providing structural support for the orbiting research facility's radiator panels that cool the Space Station's complex power system. The S1 truss segment also will house communications systems, external experiment positions and other subsystems. Primarily constructed of aluminum, the truss segment is 45 feet long, 15 feet wide and 6 feet tall. When fully outfitted, it will weigh 31,137 pounds. The truss is slated for flight in 2001. The truss arrived at KSC aboard NASA's Super Guppy, seen in the background. The aircraft is uniquely built with a 25-foot diameter fuselage designed to handle oversized loads and a 'fold-away' nose that opens 110 degrees for cargo loading. A system of rails in the cargo compartment, used with either Guppy pallets or fixtures designed for specific cargo, makes cargo loading simple and efficient. Rollers mounted in the rails allow pallets or fixtures to be moved by an electric winch mounted beneath the cargo floor. Automatic hydraulic lock pins in each rail secure the pallet for flight

1999-01-01

154

STS-112 S1 Truss Payload arrives at KSC  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- NASA's Super Guppy airplane, with the International Space Station's (ISS) S1 truss aboard, rolls to a stop at KSC's Shuttle Landing Facility. Manufactured by the Boeing Co. in Huntington Beach, Calif., this component of the I SS is the first starboard (right-side) truss segment, whose main job is providing structural support for the orbiting research facility's radiator panels that cool the Space Station's complex power system. The S1 truss segment also will house communicatio ns systems, external experiment positions and other subsystems. Primarily constructed of aluminum, the truss segment is 45 feet long, 15 feet wide and 6 feet tall. When fully outfitted, it will weigh 31,137 pounds. The truss is slated for flight in 2001. The Super Guppy, with its 25-foot diameter fuselage designed to handle oversized loads, is well prepared to transport the truss and other ISS segments. Loading the Guppy is easy because of the unique 'fold-away' nose of the aircraft that opens 110 degrees for cargo loading. A system of rails in the cargo compartment, used with either Guppy pallets or fixtures designed for specific cargo, makes cargo loading simple and efficient. Rollers mounted in the rails allow pallets or fixtures to be moved by an elec tric winch mounted beneath the cargo floor. Automatic hydraulic lock pins in each rail secure the pallet for flight. The truss is to be transferred to the Operations and Checkout Building

1999-01-01

155

STS-112 S1 Truss Payload arrives at KSC  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- NASA's Super Guppy airplane, with the International Space Station's (ISS) S1 truss aboard, arrives at KSC's Shuttle Landing Facility from Marshall Space Flight Center. Manufactured by the Boeing Co. in Huntington Beach, Calif ., this component of the ISS is the first starboard (right-side) truss segment, whose main job is providing structural support for the orbiting research facility's radiator panels that cool the Space Station's complex power system. The S1 truss segment al so will house communications systems, external experiment positions and other subsystems. Primarily constructed of aluminum, the truss segment is 45 feet long, 15 feet wide and 6 feet tall. When fully outfitted, it will weigh 31,137 pounds. The truss is s lated for flight in 2001. The Super Guppy, with its 25-foot diameter fuselage designed to handle oversized loads, is well prepared to transport the truss and other ISS segments. Loading the Guppy is easy because of the unique 'fold-away' nose of the aircr aft that opens 110 degrees for cargo loading. A system of rails in the cargo compartment, used with either Guppy pallets or fixtures designed for specific cargo, makes cargo loading simple and efficient. Rollers mounted in the rails allow pallets or fixtu res to be moved by an electric winch mounted beneath the cargo floor. Automatic hydraulic lock pins in each rail secure the pallet for flight. The truss is to be moved to the Operations and Checkout Building

1999-01-01

156

Sphingosine 1-phosphate (S1P) induces COX-2 expression and PGE2 formation via S1P receptor 2 in renal mesangial cells.  

PubMed

Understanding the mechanisms of sphingosine 1-phosphate (S1P)-induced cyclooxygenase (COX)-2 expression and prostaglandin E2 (PGE2) formation in renal mesangial cells may provide potential therapeutic targets to treat inflammatory glomerular diseases. Thus, we evaluated the S1P-dependent signaling mechanisms which are responsible for enhanced COX-2 expression and PGE2 formation in rat mesangial cells under basal conditions. Furthermore, we investigated whether these mechanisms are operative in the presence of angiotensin II (Ang II) and of the pro-inflammatory cytokine interleukin-1? (IL-1?). Treatment of rat and human mesangial cells with S1P led to concentration-dependent enhanced expression of COX-2. Pharmacological and molecular biology approaches revealed that the S1P-dependent increase of COX-2 mRNA and protein expression was mediated via activation of S1P receptor 2 (S1P2). Further, inhibition of Gi and p42/p44 MAPK signaling, both downstream of S1P2, abolished the S1P-induced COX-2 expression. In addition, S1P/S1P2-dependent upregulation of COX-2 led to significantly elevated PGE2 levels, which were further potentiated in the presence of Ang II and IL-1?. A functional consequence downstream of S1P/S1P2 signaling is mesangial cell migration that is stimulated by S1P. Interestingly, inhibition of COX-2 by celecoxib and SC-236 completely abolished the migratory response. Overall, our results demonstrate that extracellular S1P induces COX-2 expression via activation of S1P2 and subsequent Gi and p42/p44 MAPK-dependent signaling in renal mesangial cells leading to enhanced PGE2 formation and cell migration that essentially requires COX-2. Thus, targeting S1P/S1P2 signaling pathways might be a novel strategy to treat renal inflammatory diseases. PMID:24064301

Völzke, Anja; Koch, Alexander; Meyer Zu Heringdorf, Dagmar; Huwiler, Andrea; Pfeilschifter, Josef

2014-01-01

157

S1P lyase in thymic perivascular spaces promotes egress of mature thymocytes via up-regulation of S1P receptor 1.  

PubMed

Sphingosine 1-phosphate (S1P) and S1P receptor 1 (S1P1) play an important role in the egress of mature CD4 or CD8 single-positive (SP) thymocytes from the thymus. Fingolimod hydrochloride (FTY720), an S1P1 functional antagonist, induced significant accumulation of CD62L(high)CD69(low) mature SP thymocytes in the thymic medulla. Immunohistochemical staining using anti-S1P1 antibody revealed that S1P1 is predominantly expressed on thymocytes in the thymic medulla and is strongly down-regulated even at 3h after FTY720 administration. 2-Acetyl-4-tetrahydroxybutylimidazole (THI), an S1P lyase inhibitor, also induced accumulation of mature SP thymocytes in the thymic medulla with an enlargement of the perivascular spaces (PVS). At 6h after THI administration, S1P1-expressing thymocytes reduced partially as if to form clusters and hardly existed in the proximity of CD31-expressing blood vessels in the thymic medulla, suggesting S1P lyase expression in the cells constructing thymic medullary PVS. To determine the cells expressing S1P lyase in the thymus, we newly established a mAb (YK19-2) specific for mouse S1P lyase. Immunohistochemical staining with YK19-2 revealed that S1P lyase is predominantly expressed in non-lymphoid thymic stromal cells in the thymic medulla. In the thymic medullary PVS, S1P lyase was expressed in ER-TR7-positive cells (reticular fibroblasts and pericytes) and CD31-positive vascular endothelial cells. Our findings suggest that S1P lyase expressed in the thymic medullary PVS keeps the tissue S1P concentration low around the vessels and promotes thymic egress via up-regulation of S1P1. PMID:24343820

Maeda, Yasuhiro; Yagi, Hideki; Takemoto, Kana; Utsumi, Hiroyuki; Fukunari, Atsushi; Sugahara, Kunio; Masuko, Takashi; Chiba, Kenji

2014-05-01

158

Percentage Points of the Joint Distribution of the Extreme Roots of the Random Matrix S(1)(S(1)+S(2))(Sup(-1)).  

National Technical Information Service (NTIS)

Let S(1) and S(2) be independently distributed as central Wishart matrices with n(1) and n(2) degrees of freedom respectively. Also, let theta sub 1 and theta sub p be the smallest and largest roots of S(1)(S(1) + S(2)) sup(-1). In this report, the author...

F. J. Schuurmann P. R. Krishnaiah V. B. Waikar

1971-01-01

159

Confinement and power balance in the S-1 spheromak  

SciTech Connect

The confinement and scaling features of the S-1 spheromak have been investigated using magnetic, spectroscopic, and Thomson scattering data in conjunction with numerical modeling. Results from the multipoint Thomson scattering diagnostic shows that the central beta remains constant (/beta//sub to/ /approximately/ 5%) as the plasma current density increases from 0.68--2.1 MA/m/sup 2/. The density is observed to increase slowly over this range, while the central electron temperature increases much more rapidly. Analysis of the global plasma parameters shows a decrease in the volume average beta and energy confinement as the total current is increased. The power balance has been modeled numerically with a 0-D non-equilibrium time-dependent coronal model and is consistent with the experimental observations. 20 refs., 12 figs., 2 tabs.

Levinton, F.M.; Meyerhofer, D.D.; Mayo, R.M.; Janos, A.C.; Ono, Y.; Ueda, Y.; Yamada, M.

1989-07-01

160

Line Operator Index on S 1 × S 3  

NASA Astrophysics Data System (ADS)

We derive a general formula of an index for {N} = 2 superconformal field theories on S1 × S3 with insertions of BPS Wilson line or 't Hooft line operator at the north pole and their anti-counterpart at the south pole of S3. One-loop and monopole bubbling effects are taken into account in the computation. As examples, we calculate the indices for {N} = 4 theories and {N} = 2 SU(2) theory with N f = 4, and find good agreements between indices of line operators related by S-duality. The relation between Verlinde loop operators and the indices is explored. The holographic correspondence between the fundamental (anti- symmetric) Wilson line operator and the fundamental string (D5 brane) in AdS5 × S5 is confirmed by the index comparison.

Gang, Dongmin; Koh, Eunkyung; Lee, Kimyeong

2012-05-01

161

S1P promotes murine progenitor cell egress and mobilization via S1P1-mediated ROS signaling and SDF-1 release  

PubMed Central

The mechanisms of hematopoietic progenitor cell egress and clinical mobilization are not fully understood. Herein, we report that in vivo desensitization of Sphingosine-1-phosphate (S1P) receptors by FTY720 as well as disruption of S1P gradient toward the blood, reduced steady state egress of immature progenitors and primitive Sca-1+/c-Kit+/Lin? (SKL) cells via inhibition of SDF-1 release. Administration of AMD3100 or G-CSF to mice with deficiencies in either S1P production or its receptor S1P1, or pretreated with FTY720, also resulted in reduced stem and progenitor cell mobilization. Mice injected with AMD3100 or G-CSF demonstrated transient increased S1P levels in the blood mediated via mTOR signaling, as well as an elevated rate of immature c-Kit+/Lin? cells expressing surface S1P1 in the bone marrow (BM). Importantly, we found that S1P induced SDF-1 secretion from BM stromal cells including Nestin+ mesenchymal stem cells via reactive oxygen species (ROS) signaling. Moreover, elevated ROS production by hematopoietic progenitor cells is also regulated by S1P. Our findings reveal that the S1P/S1P1 axis regulates progenitor cell egress and mobilization via activation of ROS signaling on both hematopoietic progenitors and BM stromal cells, and SDF-1 release. The dynamic cross-talk between S1P and SDF-1 integrates BM stromal cells and hematopoeitic progenitor cell motility.

Golan, Karin; Vagima, Yaron; Ludin, Aya; Itkin, Tomer; Cohen-Gur, Shiri; Kalinkovich, Alexander; Kollet, Orit; Kim, Chihwa; Schajnovitz, Amir; Ovadya, Yossi; Lapid, Kfir; Shivtiel, Shoham; Morris, Andrew J.; Ratajczak, Mariusz Z.

2012-01-01

162

Discovery of AMG 369, a Thiazolo[5,4-b]pyridine Agonist of S1P1 and S1P5  

PubMed Central

The optimization of a series of thiazolopyridine S1P1 agonists with limited activity at the S1P3 receptor is reported. These efforts resulted in the discovery of 1-(3-fluoro-4-(5-(1-phenylcyclopropyl)thiazolo-[5,4-b]pyridin-2-yl)benzyl)azetidine-3-carboxylic acid (5d, AMG 369), a potent dual S1P1/S1P5 agonist with limited activity at S1P3 and no activity at S1P2/S1P4. Dosed orally at 0.1 mg/kg, 5d is shown to reduce blood lymphocyte counts 24 h postdose and delay the onset and reduce the severity of experimental autoimmune encephalomyelitis in rat.

2010-01-01

163

Nature and degree of aqueous alteration in CM and CI carbonaceous chondrites  

NASA Astrophysics Data System (ADS)

We investigated the petrologic, geochemical, and spectral parameters that relate to the type and degree of aqueous alteration in nine CM chondrites and one CI (Ivuna) carbonaceous chondrite. Our underlying hypothesis is that the position and shape of the 3 ?m band is diagnostic of phyllosilicate mineralogy. We measured reflectance spectra of the chondrites under dry conditions (elevated temperatures) and vacuum (10-8 to 10-7 torr) to minimize adsorbed water and mimic the space environment, for subsequent comparison with reflectance spectra of asteroids. We have identified three spectral CM groups in addition to Ivuna. "Group 1," the least altered group as determined from various alteration indices, is characterized by 3 ?m band centers at longer wavelengths, and is consistent with cronstedtite (Fe-serpentine). "Group 3," the most altered group, is characterized by 3 ?m band centers at shorter wavelengths and is consistent with antigorite (serpentine). "Group 2" is an intermediate group between group 1 and 3. Ivuna exhibits a unique spectrum that is distinct from the CM meteorites and is consistent with lizardite and chrysotile (serpentine). The petrologic and geochemical parameters, which were determined using electron microprobe analyses and microscopic observations, are found to be consistent with the three spectral groups. These results indicate that the distinct parent body aqueous alteration environments experienced by these carbonaceous chondrites can be distinguished using reflectance spectroscopy. High-quality ground-based telescopic observations of Main Belt asteroids can be expected to reveal not just whether an asteroid is hydrated, but also details of the alteration state.

Takir, Driss; Emery, Joshua P.; McSween, Harry Y.; Hibbitts, Charles A.; Clark, Roger N.; Pearson, Neil; Wang, Alian

2013-09-01

164

Lessons Learned From CM-2 Modal Testing and Analysis  

NASA Technical Reports Server (NTRS)

The Combustion Module-2 (CM-2) is a space experiment that launches on Shuttle mission STS-107 in the SPACEHAB Double Research Module. The CM-2 flight hardware is installed into SPACEHAB single and double racks. The CM-2 flight hardware was vibration tested in the launch configuration to characterize the structure's modal response. Cross-orthogonality between test and analysis mode shapes were used to assess model correlation. Lessons learned for pre-test planning and model verification are discussed.

McNelis, Mark E.; Goodnight, Thomas W.; Carney, Kelly S.; Otten, Kim D.

2002-01-01

165

Development of COMS DATS C&M S/W  

NASA Astrophysics Data System (ADS)

COMS DATS C&M software is an integrated management system providing control and monitoring functionalities for COMS IDACS (Image Data Acquisition and Control System). DATS C&M S/W consists of a system management module, a control and monitoring module, a data management module, and a trend analysis module. COMS SOC is supposed to operate IDACS as a backup of MSC. Especially, for the backup operation, the control and monitoring module of DATS C&M S/W is designed to support the synchronization of the two IDACS systems. This paper describes design, implementation, and result of development of DATS C&M S/W.

Kim, Su-Jin; Park, Durk-Jong; Koo, In-Hoi; Ahn, Sang-Il

2009-03-01

166

Effects of electron irradiation and temperature on 1 ohm-cm and 10 ohm-cm silicon solar cells  

NASA Technical Reports Server (NTRS)

One OHM-cm and 10 OHM-cm silicon solar cells were exposed to 1.0 MeV electrons at a fixed flux of 10 to the 11th power e/sq cm/sec and fluences of 10 to the 13th power, 10 to the 14th power and 10 to the 15th power e/sq.cm. 1-V curves of the cells were made at room temperature, - 63 C and + or - 143 C after each irradiation. A value of 139.5 mw/sq cm was used as AMO incident energy rate per unit area. The 10 OHM-cm cells appear more efficient than 1 OHM-cm cells after exposure to a fluence greater than 10 to the 14th power e/sq cm. The 1.0 MeV electron damage coefficients for both 1 OHM-cm and 10 OHM-cm cells are somewhat less than those for previously irradiated cells at room temperature. The values of the damage coefficients increase as the cell temperatures decrease. Efficiencies pertaining to maximum power output are about the same as those of n on p silicon cells evaluated previously.

Nicoletta, C. A.

1973-01-01

167

Pattern identification in systems with S(1) symmetry  

NASA Astrophysics Data System (ADS)

This work is devoted to pattern identification in systems with S(1) symmetry based on limited experimental data. As we demonstrate, such pattern identification is complicated by the lack of a theoretical basis as well as by the presence of experimental uncertainties, and possible overlapping and missing points in the data. The study is motivated by a recent finding of physical systems where instabilities of different wave numbers may coexist and thus lead to several single-wave-number patterns superimposed with a random phase-shift between them. As shown in this work, such patterns cannot be identified with Fourier analysis as well as direct measurement of the wave numbers is not possible. We present both a constructive theoretical approach, which establishes the conditions under which the structure of such patterns is identifiable, and an example of application—the crown structure analysis in the drop splash problem. For the latter study, an experimental setup is developed based on high-speed stereo photography, which produces data suitable for a quantitative analysis of the observed patterns.

Hartong-Redden, Rory; Krechetnikov, Rouslan

2011-11-01

168

Final report on EURAMET.AUV.A-S1  

NASA Astrophysics Data System (ADS)

The supplementary Regional Comparison EURAMET.AUV.A-S1 has been carried out under the auspices of EURAMET's Technical Committee for Acoustics, Ultrasound and Vibration, and the Consultative Committee for Acoustics, Ultrasound and Vibration (CCAUV) of the International Bureau of Weights and Measures (BIPM). The participating NMIs are the Centro Nacional de Metrología (CENAM, Mexico), the Danish Fundamental Metrology (DFM, Denmark) and the Directorate of Measures and Precious Metals (DMDM, Serbia). The role of the Pilot laboratory was jointly undertaken by the DFM and CENAM. The time schedule was organized in a single star configuration. Two LS1P microphones and two LS2aP were circulated among participants. This report includes the measurement results from the participants, and the analysis leading to a proposal for the reference values for the comparison. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCAUV, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Barrera-Figueroa, Salvador; Nielsen, Lars

2013-01-01

169

Magnetic susceptibilities of rectangular Heisenberg S=1/2 antiferromagnets  

NASA Astrophysics Data System (ADS)

Rectangular antiferromagnets are two-dimensional systems with inequivalent exchange strengths (J', J) along the two principle axes with J' ? ?J, ? <1. They have an intermediate dimensionality that can vary continuously from 1D (? = 0 ) to square 2D (? = 1). There exist a number of physical realizations of rectangular antiferromagnets (CuPzBr2, CuPzCl2, CuPz(N3)2 where Pz = pyrazine) but there has been no previous mechanism for interpreting their susceptibilities in terms of two exchange parameters. We have simulated the susceptibility of the rectangular S=1/2 Heisenberg antiferromagnet using the stochastic series expansion quantum Monte Carlo method [1] and used the results to interpret our experimental data. For example, copper pyrazine diazide, CuPz(N3)2, has a primary exchange of 15.5 K and an anisotropy parameter ? = 0.4. The stronger exchange is due to the superexchange pathway through the pyrazine molecule and the weaker corresponds to the azide bridges. [1] A. Sandvik, PRB 59, R14157 (1999).

Valleau, Tom; Butcher, Rob; Keith, Brian; Landee, Christopher; Turnbull, Mark; Sandvik, Anders

2008-03-01

170

The sphingosine 1-phosphate receptor S1P2 triggers hepatic wound healing  

Microsoft Academic Search

Sphingosine 1-phosphate (S1P) is a bio- active sphingolipid produced by sphingosine kinase (SphK1 and 2). We previously showed that S1P recep- tors (S1P1, S1P2, and S1P3) are expressed in hepatic myofibroblasts (hMF), a population of cells that trig- gers matrix remodeling during liver injury. Here we investigated the function of these receptors in the wound healing response to acute liver

Valerie Serriere-Lanneau; Fatima Teixeira-Clerc; Liying Li; Marlies Schippers; Willie de Wries; Boris Julien; Jeanne Tran-Van-Nhieu; Sylvie Manin; Klaas Poelstra; Jerold Chun; Stephane Carpentier; Thierry Levade; Ariane Mallat; Sophie Lotersztajn

2007-01-01

171

Berberine Reduces Fibronectin Expression by Suppressing the S1P-S1P2 Receptor Pathway in Experimental Diabetic Nephropathy Models  

PubMed Central

The accumulation of glomerular extracellular matrix (ECM) is one of the critical pathological characteristics of diabetic renal fibrosis. Fibronectin (FN) is an important constituent of ECM. Our previous studies indicate that the activation of the sphingosine kinase 1 (SphK1)-sphingosine 1- phosphate (S1P) signaling pathway plays a key regulatory role in FN production in glomerular mesangial cells (GMCs) under diabetic condition. Among the five S1P receptors, the activation of S1P2 receptor is the most abundant. Berberine (BBR) treatment also effectively inhibits SphK1 activity and S1P production in the kidneys of diabetic models, thus improving renal injury. Based on these data, we further explored whether BBR could prevent FN production in GMCs under diabetic condition via the S1P2 receptor. Here, we showed that BBR significantly down-regulated the expression of S1P2 receptor in diabetic rat kidneys and GMCs exposed to high glucose (HG) and simultaneously inhibited S1P2 receptor-mediated FN overproduction. Further, BBR also obviously suppressed the activation of NF-?B induced by HG, which was accompanied by reduced S1P2 receptor and FN expression. Taken together, our findings suggest that BBR reduces FN expression by acting on the S1P2 receptor in the mesangium under diabetic condition. The role of BBR in S1P2 receptor expression regulation could closely associate with its inhibitory effect on NF-?B activation.

Lan, Tian; Xie, Xi; Peng, Jing; Huang, Juan; Wang, Shaogui; Shen, Xiaoyan; Liu, Peiqing; Huang, Heqing

2012-01-01

172

Observing Comet C/2012 S1 (ISON) With Spitzer  

NASA Astrophysics Data System (ADS)

In this talk we discuss the design, implementation, and reduction of observations of Comet ISON from space using the Spitzer Space Telescope on 13.00 - 13.96 Jun UT and from the ground at Lowell Observatory on Jun 11.16 UT and from APO on 14.13 Jun UT. The comet was at distance rh = 3.34 AU from the Sun, distance ?Spitzer = 3.29 AU and 17.4o phase from SST, and distance ?Earth = 4.25 AU and 6.8 - 7.3o phase at the time of observation. Preliminary analyses show ISON's Spitzer coma morphology was relatively compact and simple, with a linear anti-solar dust tail > 3x105 km in length and a 1/p profile gas coma extending > 105 km from the nucleus. Afp values in an 18,200 km radius aperture of 840, 890, and 840 ± 80 cm were found at VRI, and 650 ± 100 cm were found at 3.6 micron. Together, the ground-based and Spitzer photometry imply near-neutral dust scattering from the visual through the infrared. An excess at 4.5 µm due to emission from a neutral gas coma is clearly found both morphologically and photometrically. The gas coma total flux and spatial profile and ISON’s discovery distance imply a coma dominated by the stronger CO_2 line emission at 4.67 ?m, but we cannot rule out a preponderance of CO emission at 4.26 ?m. No variability in our Spitzer photometry at the 0.03 mag level over 24 hrs was seen. We present our imagery, spectrophotometry, and lightcurves, and discuss the physical implications of these measurements of the comet made well outside the ice line.

Lisse, Carey M.; Vervack, R. J.; Weaver, H. A.; Bauer, J. M.; Fernandez, Y. R.; Kelley, M. S.; Knight, M. M.; Hines, D. C.; Li, J.; Reach, W. T.; Sitko, M. L.; Yanamandra-Fisher, P.; Meech, K. J.; Rayner, J. T.

2013-10-01

173

"The 5 cm Rule": Biopower, Sexuality and Schooling  

ERIC Educational Resources Information Center

This paper explores "the 5 cm rule", a regulation around student contact discovered during an investigation of the sexual culture of schooling with 16-19-year-olds in New Zealand. Implemented to stem "inappropriate and unwanted" touching, it stipulates that students must maintain a physical distance of 5 cm at all times. It is argued this rule…

Allen, Louisa

2009-01-01

174

CM-SAF high-resolution radiation budget products  

Microsoft Academic Search

In this paper the system employed at the Royal Meteorological Institute of Belgium (RMIB) within the Climate Monitoring Satellite Application Facility (CM-SAF) for the production of Top Of the Atmosphere (TOA) radiation budget components is described. One of the goals of the CM-SAF is to provide consistent TOA and surface radiation budget components and cloud properties at high spatial resolution

Bogdan Nicula; Steven Dewitte; Nicolas Clerbaux

2003-01-01

175

Tank testing of a 2500-cm2 solar panel  

Microsoft Academic Search

A 50 cm by 50 cm solar array panel test patch was investigated for spacecraft charging and arcing effects. Bombardment with monochromatic electron was carried out. Some objectives of the test were: (1) to estimate at what voltage of electron bombardment arcing would be probable (2) to find whether the arc's energy would be tolerable or damagingly large (3) to

R. S. Bever; J. Staskus

1981-01-01

176

Design and Performance of 40 cm Ion Optics  

NASA Technical Reports Server (NTRS)

A 40 cm ion thruster is being developed at the NASA Glenn Research Center to obtain input power and propellant throughput capabilities of 10 kW and 550 kg. respectively. The technical approach here is a continuation of the "derating" technique used for the NSTAR ion thruster. The 40 cm ion thruster presently utilizes the NSTAR ion optics aperture geometry to take advantage of the large database of lifetime and performance data already available. Dome-shaped grids were chosen for the design of the 40 cm ion optics because this design is naturally suited for large-area ion optics. Ion extraction capabilities and electron backstreaming limits for the 40 cm ion optics were estimated by utilizing NSTAR 30 cm ion optics data. A preliminary service life assessment showed that the propellant throughput goal of 550 kg of xenon may be possible with molybdenum 40 cm ion optics. One 40 cm ion optics' set has been successfully fabricated to date. Additional ion optics' sets are presently being fabricated. Preliminary performance tests were conducted on a laboratory model 40 cm ion thruster.

Soulas, George C.

2001-01-01

177

Photofraction of a 5 cm x 2 cm BGO scintillator. [bismuth germanate crystal for use in cosmic gamma ray detector  

NASA Technical Reports Server (NTRS)

The photofraction of a 5.1 cm x 2.0 cm bismuth germanate (BGO) scintillator was measured over a gamma-ray energy range of 0.2 to 6.1 MeV. Several methods, used to minimize the effect of room scattering on the measurement, are discussed. These include a gamma-gamma coincidence technique, a beta-gamma coincidence technique, and the use of sources calibrated with a standard 7.6 cm x 7.6 cm sodium iodide scintillator.

Dunphy, P. P.; Forrest, D. J.

1985-01-01

178

Radiofrequency ablation of hepatocellular carcinoma sized > 3 and <= 5 cm: Is ablative margin of more than 1 cm justified?  

PubMed Central

AIM: To investigate whether an ablative margin (AM) > 1.0 cm might reduce chance of recurrence for patients with hepatocellular carcinoma (HCC) tumors 3.1 to 5.0 cm in size, compared with an AM of 0.5-1.0 cm. METHODS: From October 2005 to December 2012, 936 consecutive patients with HCC who received radiofrequency ablation were screened. Of these, 281 patients, each with a single primary HCC tumor of 3.1 to 5.0 cm in size on its greatest diameter, were included in the study. Based on the AM width, we categorized patients into the 0.5-1.0 cm group and the > 1.0 cm group. Local tumor progression (LTP)-free survival, intrahepatic distant recurrence (IDR)-free survival and overall survival (OS) rates were obtained using the Kaplan-Meier method. RESULTS: The 1-, 2-, 3-, 4-, and 5-year LTP-free survival rates and IDR-free survival rates were significantly higher in the > 1.0 cm group compared with the 0.5-1.0 cm group (97.5%, 86.3%, 73.6%, 49.5% and 26.4% vs 91.3%, 78.4%, 49.5%, 27.8%, and 12.8%; 95.1%, 90.3%, 77.0%, 61.0% and 48.3% vs 95.2%, 85.9%, 62.6%, 47.2% and 28.5%; P < 0.05). The 1-, 2-, 3-, 4-, and 5-year OS rates were 98.6%, 91.5%, 69.2%, 56.0% and 42.2%, respectively, in the 0.5-1.0 cm group and 100%, 98.9%, 90.1%, 68.7% and 57.4%, respectively, in the > 1.0 cm group (P = 0.010). There were no significant differences in complication rates between the two groups. Both univariate and multivariate analyses identified AM as an independent prognostic factor linked to LTP, IDR, and OS. CONCLUSION: For HCC tumors > 3.0 cm and ? 5.0 cm, AM > 1.0 cm could reduce chances of recurrence compared with AM of 0.5-1.0 cm, emphasizing the need for a more defensive strategy using AMs > 1.0 cm for ablating HCC tumors of 3.1 to 5.0 cm.

Ke, Shan; Ding, Xue-Mei; Qian, Xiao-Jun; Zhou, Yi-Ming; Cao, Bao-Xin; Gao, Kun; Sun, Wen-Bing

2013-01-01

179

The Semidiurnal Westward s=1 Tide in the Stratosphere  

NASA Astrophysics Data System (ADS)

The semidiurnal westward propagating zonal wavenumber 1 tide (2, 1) is the dominant tide in the high- latitude wind field in the upper mesosphere during the late spring and summer. Observed peak wind speeds are ~ 30 m/s. Simulations agree with observations in showing a dominant (2, 1) tide in the upper mesosphere with about the correct amplitude at high polar latitudes. In model simulations the (2, 1) tide originates in a nonlinear interaction between the migrating semidiurnal tide (2, 2) and a stationary s=1 planetary wave. The interaction occurs in the stratosphere and mesosphere. However, stationary planetary waves are essentially absent from the summertime stratosphere and mesosphere so the occurrence of the predicted (2, 1) tide in the summer mesosphere originates via an interaction in the winter hemisphere. Observations and simulations in the mesosphere indicate a connection with the zero wind line in the zonally averaged zonal winds. The models (Angelas i Coll and Forbes, 2002, Aso, 2007) agree in showing that the (2,1) tide is confined to the upper mesosphere. We have analyzed results from the GEOS-5 assimilation model and find a significant stratospheric (2, 1) tide. We have also analyzed balloon data from the CNES VORCORE campaign in which a total of 27 balloons drifted in the Antarctic polar stratospheric vortex during the late summer and spring of 2005, and confirm the existence of the (2, 1) tide. This is the first observation of a (2, 1) tide in the stratosphere insofar as we are aware. The existence of this tide in the stratosphere is hard to understand in terms of energy propagation from the winter hemisphere guided by the zero wind line, since this would guide energy into the mesosphere rather than the stratosphere. We will present the height- latitude structure of the (2, 1) tide in the Antarctic spring and will show its correlation with the zero wind line and wave energy flux found from the GEOS-5 data assimilation model.

Mechoso, C. R.; Walterscheid, R. L.; Gelinas, L. J.; Schubert, G.

2008-12-01

180

Ultraviolet Observations Of C/2012 S1 (ISON) By MAVEN  

NASA Astrophysics Data System (ADS)

On its journey to Mars, MAVEN has been serendipitously positioned to study the anticipated sungrazing comet C/2012 S1(ISON) and offers important scientific observations. The MAVEN mission is the first to attempt to understand the evolution of the Martian atmosphere by determining the effects of atmospheric loss to space. The IUVS instrument has two large field of regard(55x11 and 24x11 degrees) and observes in the mid and far ultraviolet (115-340 nm). It was designed to be able to map the atmosphere in several neutral and some ionized species. These performance characteristics make IUVS ideal to study ISON, as it can take both two dimensional spatial scans as well as spectral data. Tentative plans indicate the comet can be acquired on Dec 8th, assuming that the comet survives the near sun encounter. If observations prove possible, IUVS will be able to study ISON shortly after perihelion, and from a different vantage point from Earth. Science goals include UV observations of D/H, morphology & time evolution of the hydrogen coma and UV spectroscopy of the inner coma. IUVS can potentially make a major contribution to the international community by measuring D/H, thus contributing to our understanding of the origin of Earth’s water. IUVS will also make MUV and FUV observations of molecular species in the inner coma, valuable for understanding the chemical evolution of cometary molecular gases. The poster will present provisional observation plans as well as simulated spectra and spatial profiles. We welcome input from the community on these plans, in the spirit of maximizing the scientific return of the international campaign. The work has been supported by the MAVEN project and NASA Planetary Atmospheres grant NNX09AB59G.

Crismani, Matteo; Schneider, N.; Stewart, I.; Combi, M.; Fougere, N.

2013-10-01

181

The turbomachine blading design using S2-S1 approach  

NASA Technical Reports Server (NTRS)

The boundary conditions corresponding to the design problem when the blades being simulated by the bound vorticity distribution are presented. The 3D flow is analyzed by the two steps S2 - S1 approach. In the first step, the number of blades is supposed to be infinite, the vortex distribution is transformed into an axisymmetric one, so that the flow field can be analyzed in a meridional plane. The thickness distribution of the blade producing the flow channel striction is taken into account by the modification of metric tensor in the continuity equation. Using the meridional stream function to define the flow field, the mass conservation is satisfied automatically. The governing equation is deduced from the relation between the azimuthal component of the vorticity and the meridional velocity. The value of the azimuthal component of the vorticity is provided by the hub to shroud equilibrium condition. This step leads to the determination of the axisymmetric stream sheets as well as the approximate camber surface of the blade. In the second step, the finite number of blades is taken into account, the inverse problem corresponding to the blade to blade flow confined in each stream sheet is analyzed. The momentum equation implies that the free vortex of the absolute velocity must be tangential to the stream sheet. The governing equation for the blade to blade flow stream function is deduced from this condition. At the beginning, the upper and the lower surfaces of the blades are created from the camber surface obtained from the first step with the assigned thickness distribution. The bound vorticity distribution and the penetrating flux conservation applied on the presumed blade surface constitute the boundary conditions of the inverse problem. The detection of this flux leads to the rectification of the geometry of the blades.

Luu, T. S.; Bencherif, L.; Viney, B.; Duc, J. M. Nguyen

1991-01-01

182

Gravitational dynamics in s+1+1 dimensions  

SciTech Connect

We present the concomitant decomposition of an (s+2)-dimensional space-time both with respect to a timelike and a spacelike direction. The formalism we develop is suited for the study of the initial value problem and for canonical gravitational dynamics in braneworld scenarios. The bulk metric is replaced by two sets of variables. The first set consists of one tensorial (the induced metric g{sub ij}), one vectorial (M{sup i}) and one scalar (M) dynamical quantity, all defined on the s space. Their time evolutions are related to the second fundamental form (the extrinsic curvature K{sub ij}), the normal fundamental form (K{sup i}) and normal fundamental scalar (K), respectively. The nondynamical set of variables is given by the lapse function and the shift vector, which however has one component less. The missing component is due to the externally imposed constraint, which states that physical trajectories are confined to the (s+1)-dimensional brane. The pair of dynamical variables (g{sub ij}, K{sub ij}), well known from the Arnowitt-Deser-Misner decomposition is supplemented by the pairs (M{sup i}, K{sup i}) and (M, K) due to the bulk curvature. We give all projections of the junction condition across the brane and prove that for a perfect fluid brane neither of the dynamical variables has jump across the brane. Finally we complete the set of equations needed for gravitational dynamics by deriving the evolution equations of K{sub ij}, K{sup i} and K on a brane with arbitrary matter.

Gergely, Laszlo A. [Departments of Theoretical and Experimental Physics, University of Szeged, Szeged 6720, Dom ter 9 (Hungary); Kovacs, Zoltan [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany)

2005-09-15

183

S-1 combined with docetaxel following doxorubicin plus cyclophosphamide as neoadjuvant therapy in breast cancer: phase II trial  

PubMed Central

Background This study evaluated the efficacy and safety of S-1 combined with docetaxel (SD) following doxorubicin plus cyclophosphamide (AC) as neoadjuvant therapy in patients with HER2-negative, stage II-III breast cancer. Methods Patients received AC every 3 weeks for four cycles followed by S-1 (30 mg/m2 orally b.i.d. on days 1–14) and docetaxel (75 mg/m2 i.v. on day 1) every 3 weeks for four cycles. The primary endpoint was the pathological complete response (pCR) rate in breast and axillary lymph nodes. Results The study included 49 patients with a median age of 43 years. The median breast tumor size was 4.0 cm by palpation. All patients were positive for involvement of axillary lymph node and five patients also had supraclavicular lymph node metastasis, which was confirmed by histological examination. In total, 85.4% of patients (41/49) completed eight cycles of therapy and 95.9% of patients (47/49) received curative surgery. The pCR rate was 22.5% (n = 11). The clinical response rate was 67.4%. During SD chemotherapy, the most frequent grade 3–4 toxicity was neutropenia (8.5% by cycle). There was a single treatment-related mortality from severe neutropenia. Grade 3 S-1 specific toxicities such as epigastric pain (12.2% by person), stomatitis (4.1% by person), and diarrhea (2.0% by person) were also observed. In particular, gastrointestinal discomfort led to dose reduction of S-1 in 45.8% of patients. Conclusions Given all axillary lymph node positive diseases, neoadjuvant S-1 combined with docetaxel following AC showed a favorable anti-tumor activity but gastrointestinal discomfort should be carefully considered for future studies. Trial registration NCT00994968

2013-01-01

184

Dynamin 2-dependent endocytosis is required for sustained S1PR1 signaling.  

PubMed

Sphingosine-1-phosphate (S1P) receptor 1 (S1PR1) is critical for lymphocyte egress from lymphoid organs. Lymphocytes encounter low S1P concentrations near exit sites before transmigration, yet S1PR1 signaling is rapidly terminated after exposure to S1P. How lymphocytes maintain S1PR1 signaling in a low S1P environment near egress sites is unknown. Here we identify dynamin 2, an essential component of endocytosis, as a novel regulator of T cell egress. Mice with T cell-specific dynamin 2 deficiency had profound lymphopenia and impaired egress from lymphoid organs. Dynamin 2 deficiency caused impaired egress through regulation of S1PR1 signaling, and transgenic S1PR1 overexpression rescued egress in dynamin 2 knockout mice. In low S1P concentrations, dynamin 2 was essential for S1PR1 internalization, which enabled continuous S1PR1 signaling and promoted egress from both thymus and lymph nodes. In contrast, dynamin 2-deficient cells were only capable of a pulse of S1PR1 signaling, which was insufficient for egress. Our results suggest a possible mechanism by which T lymphocytes positioned at exit portals sense low S1P concentrations, promoting their egress into circulatory fluids. PMID:24638168

Willinger, Tim; Ferguson, Shawn M; Pereira, João P; De Camilli, Pietro; Flavell, Richard A

2014-04-01

185

Development of Activity in Comet C/2012 S1 ISON  

NASA Astrophysics Data System (ADS)

We report photometric observations for comet C/2012 S1 ISON obtained immediately after discovery (22 Sep. 2012; r = 6.28 AU) until moving into solar conjunction in mid-June 2013 using the UH2.2m, and Gemini North 8-m telescopes on Mauna Kea, the Lowell 1.8m in Flagstaff, the Calar Alto 1.2m telescope in Spain, and the VYSOS-5 and VYSOS-20 telescopes on Mauna Loa Hawai'i. An additional pre-discovery data point from the Pan STARRS1 survey extends the light curve back to 28 Jan. 2012 (r = 8.4 AU). The images showed similar tail morphology throughout this period, largely because of projection effects. Additional observations at sub-mm wavelengths using the JCMT on 15 nights between 9 March (r = 4.52 AU) and 16 June 2013 (r = 3.35 AU) were used to search for CO J(3-2), CO J(2-1), HCN J(4-3), and HCN J(3-2) rotation lines. No gas was detected, with preliminary upper limits for CO during 14-15 June (r = 3.3 AU) of Q < 6.4 x 10^27 molec/s based on the observations of the CO J(2-1) line. Using these production rates, the Q(H2O) published by Schleicher (2013; IAUC 9254), and the preliminary radius from the HST measurements (J.-Y. Li et al., 2013; STScI-2013-14) we have generated ice sublimation models consistent with the photometric light curve. The inbound light curve is likely controlled by sublimation of CO or CO2; at these distances water is not a strong contributor to the outgassing. Without more sensitive limits on CO, we cannot yet constrain which of these volatiles is controlling the activity. It is clear from the photometric light curve that the fractional active area of the nucleus increased linearly by about a factor of 2 from Jan. 2012 until mid Jan. 2013 (r ~ 5 AU) at which point the activity decreased by 30% by early May 2013. We will discuss these models and data obtained from Mauna Kea after the comet comes out of solar conjunction in late August 2013. Our team has a comprehensive plan of observation to look at the evolution of activity as the comet goes through perihelion (on 28 November, 2013), with investigations to look at volatile production, and characterization of the dust. We will summarize early results from the University of Hawaii Mauna Kea observing campaign.

Meech, K. J.; Yang, B.; Keane, J.; Ansdell, M.; Riesen, T.; Kleyna, J.; Hsieh, H.; Mottola, S.; Kuhrt, E.; Chiang, H.; Reipurth, B.; Michaud, P.; Rector, T.

2013-12-01

186

Development of Activity in Comet C/2012 S1 ISON  

NASA Astrophysics Data System (ADS)

We report photometric observations for comet C/2012 S1 ISON obtained immediately after discovery (22 Sep. 2012; r = 6.28 AU) until moving into solar conjunction in mid-June 2013 using the UH2.2m, and Gemini North 8-m telescopes on Mauna Kea, the Lowell 1.8m in Flagstaff, the Calar Alto 1.2m telescope in Spain, and the VYSOS-5 and VYSOS-20 telescopes on Mauna Loa Hawai’i. An additional pre-discovery data point from the Pan STARRS1 survey extends the light curve back to 28 Jan. 2012 (r = 8.4 AU). The images showed similar tail morphology throughout this period, largely because of projection effects. Additional observations at sub-mm wavelengths using the JCMT on 15 nights between 9 March (r = 4.52 AU) and 16 June 2013 (r = 3.35 AU) were used to search for CO J(3-2), CO J(2-1), HCN J(4-3), and HCN J(3-2) rotation lines. No gas was detected, with preliminary upper limits for CO during 14-15 June (r = 3.3 AU) of Q < 6.4 x 10^27 molec/s based on the observations of the CO J(2-1) line. Using these production rates, the Q(H2O) published by Schleicher (2013; IAUC 9254), and the preliminary radius from the HST measurements (J.-Y. Li et al., 2013; STScI-2013-14) we have generated ice sublimation models consistent with the photometric light curve. The inbound light curve is likely controlled by sublimation of CO or CO2; at these distances water is not a strong contributor to the outgassing. Without more sensitive limits on CO, we cannot yet constrain which of these volatiles is controlling the activity. It is clear from the photometric light curve that the fractional active area of the nucleus increased linearly by about a factor of 2 from Jan. 2012 until mid Jan. 2013 (r ~ 5 AU) at which point the activity decreased by 30% by early May 2013. This suggests that a limited supply of volatile material was driving the current activity.

Meech, Karen J.; Yang, B.; Keane, J. V.; Ansdell, M.; Riesen, T. E.; Kleyna, J.; Hsieh, H.; Mottola, S.; Kuehrt, E.; Chiang, H.; Reipurth, B.; Milani, G.; Bryssinck, E.; Michaud, P.; Rector, T.

2013-10-01

187

Ion accelerator systems for high power 30 cm thruster operation  

NASA Technical Reports Server (NTRS)

Two and three-grid accelerator systems for high power ion thruster operation were investigated. Two-grid translation tests show that over compensation of the 30 cm thruster SHAG grid set spacing the 30 cm thruster radial plasma density variation and by incorporating grid compensation only sufficient to maintain grid hole axial alignment, it is shown that beam current gains as large as 50% can be realized. Three-grid translation tests performed with a simulated 30 cm thruster discharge chamber show that substantial beamlet steering can be reliably affected by decelerator grid translation only, at net-to-total voltage ratios as low as 0.05.

Aston, G.

1982-01-01

188

Eight-cm mercury ion thruster system technology  

NASA Technical Reports Server (NTRS)

The technology status of 8 cm diameter electron bombardment ion thrusters is presented. Much of the technology resulting from the 5 cm diameter thruster has been adapted and improved upon to increase the reliability, durability, and efficiency of the 8 cm thruster. Technology discussed includes: dependence of neutralizer tip erosion upon neutralizer flow rate; impregnated and rolled-foil insert cathode performance and life testing; neutralizer position studies; thruster ion beam profile measurements; high voltage pulse ignition; high utilization ion machined accelerator grids; deposition internal and external to the thruster; thruster vectoring systems; thruster cycling life testing and thruster system weights for typical mission applications.

1974-01-01

189

A Prokaryotic S1P Lyase Degrades Extracellular S1P In Vitro and In Vivo: Implication for Treating Hyperproliferative Disorders  

PubMed Central

Sphingosine-1-phosphate (S1P) regulates a broad spectrum of fundamental cellular processes like proliferation, death, migration and cytokine production. Therefore, elevated levels of S1P may be causal to various pathologic conditions including cancer, fibrosis, inflammation, autoimmune diseases and aberrant angiogenesis. Here we report that S1P lyase from the prokaryote Symbiobacterium thermophilum (StSPL) degrades extracellular S1P in vitro and in blood. Moreover, we investigated its effect on cellular responses typical of fibrosis, cancer and aberrant angiogenesis using renal mesangial cells, endothelial cells, breast (MCF-7) and colon (HCT 116) carcinoma cells as disease models. In all cell types, wild-type StSPL, but not an inactive mutant, disrupted MAPK phosphorylation stimulated by exogenous S1P. Functionally, disruption of S1P receptor signaling by S1P depletion inhibited proliferation and expression of connective tissue growth factor in mesangial cells, proliferation, migration and VEGF expression in carcinoma cells, and proliferation and migration of endothelial cells. Upon intravenous injection of StSPL in mice, plasma S1P levels rapidly declined by 70% within 1 h and then recovered to normal 6 h after injection. Using the chicken chorioallantoic membrane model we further demonstrate that also under in vivo conditions StSPL, but not the inactive mutant, inhibited tumor cell-induced angiogenesis as an S1P-dependent process. Our data demonstrate that recombinant StSPL is active under extracellular conditions and holds promise as a new enzyme therapeutic for diseases associated with increased levels of S1P and S1P receptor signaling.

Huwiler, Andrea; Bourquin, Florence; Kotelevets, Nataliya; Pastukhov, Oleksandr; Capitani, Guido; Grutter, Markus G.; Zangemeister-Wittke, Uwe

2011-01-01

190

Radar Imaging of Mercury's North and South Poles at 3.5 cm Wavelength  

NASA Technical Reports Server (NTRS)

The Goldstone Solar System Radar has been used to image the north and south poles of Mercury during the inferior conjunctions of February 2001 and June 2001. The sub-Earth latitude was -10.7 degrees in February during observations of the southern hemisphere, and +8.4 degrees in June during observations of the northern hemisphere. These excellent viewing angles provided an opportunity to resolve the radar bright material in polar craters at 6 km range resolution. Fine-scale (1.5 km) resolution images of the northern craters have previously been obtained at 13 cm wavelengths during the July 1999 inferior conjunction. However, due to geometric constraints, the Arecibo radar cannot observe the southern polar region of Mercury until 2004. Our new Goldstone 6 km data are a factor of two higher resolution than Arecibo data collected in March 1992 at 15 km range resolution, and will remain the most highly resolved images of the south polar region for the next few years. Additional information is contained in the original extended abstract.

Harcke, L. J.; Zebker, H. A.; Jurgens, R. F.

2001-01-01

191

Carboxymethyl (CM) Cottons Prepared in Non-Aqueous Media.  

National Technical Information Service (NTIS)

The patent application concerns carboxymethyl (CM) cottons prepared in non-aqueous media. Fibrous cellulose material is impregnated with a swelling reagent, solvent exchanged to remove all water, and then reacted with an alcoholic solution of sodium metho...

D. M. Perrier R. R. Benerito

1974-01-01

192

Benchmarking and performance analysis of the CM-2. [SIMD computer  

NASA Technical Reports Server (NTRS)

A suite of benchmarking routines testing communication, basic arithmetic operations, and selected kernel algorithms written in LISP and PARIS was developed for the CM-2. Experiment runs are automated via a software framework that sequences individual tests, allowing for unattended overnight operation. Multiple measurements are made and treated statistically to generate well-characterized results from the noisy values given by cm:time. The results obtained provide a comparison with similar, but less extensive, testing done on a CM-1. Tests were chosen to aid the algorithmist in constructing fast, efficient, and correct code on the CM-2, as well as gain insight into what performance criteria are needed when evaluating parallel processing machines.

Myers, David W.; Adams, George B., II

1988-01-01

193

20. Credit CM. Water flowing through head gates (at left), ...  

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

20. Credit CM. Water flowing through head gates (at left), into open forebay of power house. Note wooden stair enclosure in Turbine pit 1. Photo c. 1936. - Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV

194

The Astronomical Station Vidojevica: The 60 cm Telescope  

NASA Astrophysics Data System (ADS)

We present the 60~cm telescope installed at the Astronomical Station Vidojevica. The telescope was mounted in September 2010, and has been in function since March 2011. The main instrumental characteristics of the telescope are discussed in this paper.

Vince, O.; Jurkovic, M.

2012-12-01

195

Management of 1-2 cm renal stones  

PubMed Central

Introduction: The preferred treatment of >1cm stone is shockwave lithotripsy (SWL), while that of stone <2 cm is percutaneous nephrolithotomy (PCNL), but treatment of 1-2 cm renal stones is a controversial issue. We searched the literature to present a comprehensive review on this group. Material and Methods: Pubmed search of literature was done using the appropriate key words. We separately discussed the literature in lower polar and non lower polar stone groups. Results: For non lower polar renal stones of 1-2 cm, SWL is preferred approach, while for the lower polar stones; literature favors the use of PCNL. Retrograde intrarenal surgery (RIRS) is emerging as a promising technique for these calculi. Conclusions: Treatment of renal stone disease depends on stone and patient related, as well as on renal anatomical factors. Treatment should be individualized according to site of stone and available expertise.

Srivastava, Aneesh; Chipde, Saurabh S

2013-01-01

196

Search for B0s-->micro+micro- and B0d-->micro+micro- decays in pp collisions at square root s = 1.96 TeV.  

PubMed

We report on a search for B(0)(s)-->micro(+)micro(-) and B(0)(d)-->micro(+)micro(-) decays in pp collisions at square root of s=1.96 TeV using 171 pb(-1) of data collected by the CDF II experiment at the Fermilab Tevatron Collider. The decay rates of these rare processes are sensitive to contributions from physics beyond the standard model. One event survives all our selection requirements, consistent with the background expectation. We derive branching ratio limits of B(B(0)(s)-->micro(+)micro(-))<5.8x10(-7) and B(B(0)(d)-->micro(+)micro(-))<1.5x10(-7) at 90% confidence level. PMID:15323815

Acousta, D; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Arguin, J-F; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Bacchetta, N; Bachacou, H; Badgett, W; Barbaro-Galtieri, A; Barker, G J; Barnes, V E; Barnett, B A; Baroiant, S; Barone, M; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C; Bloom, K; Blumenfeld, B; Bocci, A; Bodek, A; Bolla, G; Bolshov, A; Booth, P S L; Bortoletto, D; Boudreau, J; Bourov, S; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Calafiura, P; Campanelli, M; Campbell, M; Canepa, A; Casarsa, M; Carlsmith, D; Carron, S; Carosi, R; Castro, A; Catastini, P; Cauz, D; Cerri, A; Cerri, C; Cerrito, L; Chapman, J; Chen, C; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chu, M L; Chuang, S; Chung, J Y; Chung, W-H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A G; Clark, D; Coca, M; Connolly, A; Convery, M; Conway, J; Cordelli, M; Cortiana, G; Cranshaw, J; Cuevas, J; Culbertson, R; Currat, C; Cyr, D; Dagenhart, D; Da Ronco, S; D'Auria, S; de Barbaro, P; De Cecco, S; De Lentdecker, G; Dell'Agnello, S; Dell'Orso, M; Demers, S; Demortier, L; Dininno, M; De Pedis, D; Derwent, P F; Devlin, T; Dionisi, C; Dittmann, J R; Doksus, P; Dominguez, A; Donati, S; Donega, M; D'Onnofrio, M; Dorigo, T; Drollinger, V; Ebina, K; Eddy, N; Ely, R; Erbacher, R; Erdmann, M; Errede, D; Errede, S; Eusebi, R; Fang, H-C; Farrington, S; Fedorko, I; Feild, R G; Feindt, M; Fernandez, J P; Ferretti, C; Field, R D; Fiori, I; Flanagan, G; Flaugher, B; Flores-Castillo, L R; Foland, A; Forrester, S; Foster, G W; Franklin, M; Frisch, H; Fujii, Y; Furic, I; Gajjar, A; Gallas, A; Galyardt, J; Gallinaro, M; Garcia-Sciveres, M; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D W; Gerchtein, E; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Ginsburg, C; Giolo, K; Giordani, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, D; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Gondcharov, M; González, O; Gorelov, I; Goshaw, A T; Gotra, Y; Goulianos, K; Gresele, A; Grosso-Pilcher, C; Guenther, M; Guimaraes da Costa, J; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Handler, R; Happacher, F; Hara, K; Hare, M; Harr, R F; Harris, R M; Hartmann, F; Hatakeyama, K; Hauser, J; Hays, C; Hayward, H; Heider, E; Heinemann, B; Heinrich, J; Hennecke, M; Herndon, M; Hill, C; Hirschbuehl, D; Hocker, A; Hoffman, K D; Holloway, A; Hou, S; Houlden, M A; Huffman, B T; Huang, Y; Hughes, R E; Huston, J; Ikado, K; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Issever, C; Ivanov, A; Iwata, Y; Iyutin, B; James, E; Jang, D; Jarrell, J; Jeans, D; Jensen, H; Jeon, E J; Jones, M; Joo, K K; Jun, S; Junk, T; Kamon, T; Kang, J; Karagoz Unel, M; Karchin, P E; Kartal, S; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, M S; Kim, S B; Kim, S H; Kim, T H; Kim, Y K; King, B T; Kirby, M; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kobayashi, H; Koehn, P; Kong, D J; Kondo, K; Kongisberg, J; Kordas, K; Korn, A; Korytov, A; Kotelnikov, K; Kotwal, A V; Kovalev, A; Kraus, J; Kravchenko, I; Kreymer, A; Kroll, J; Kruse, M; Krutelyov, V; Kuhlmann, S E; Kuznetsova, N; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, J; Lancaster, M; Lander, R; Lannon, K; Lath, A; Latino, G; Lauhakangas, R; Lazzizzera, I; Le, Y; Lecci, C; LeCompte, T; Lee, J; Lee, J; Lee, S W; Leonardo, N; Leone, S; Lewis, J D; Li, K; Lin, C; Lin, C S; Lindgren, M; Liss, T M; Litvintsev, D O; Liu, T; Liu, Y; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lukens, P; Lyons, L; Lys, J; Lysak, R; MacQueen, D; Madrak, R; Maeshima, K; Maksimovic, P; Malferrari, L; Manca, G; Marginean, R; Martin, M; Martin, A; Martin, V; Martiínez, M; Maruyama, T; Matsunaga, H; Mattson, M; Mazzanti, P; McFarland, K S; McGivern, D; McIntyre, P M; McNamara, P; McNulty, R; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miller, L; Miller, R; Miller, J S; Miquel, R; Miscetti, S; Mitselmakher, G; Miyamoto, A; Miyazaki, Y; Moggi, N; Mohr, B; Moore, R; Morello, M; Moulik, T; Mukherjee, A; Mulhearn, M; Muller, T; Mumford, R; Munar, A; Murat, P; Nachtman, J; Nahn, S; Nakamura, I; Nakano, I; Napier, A; Napora, R; Naumov, D; Necula, V; Niell, F; Nielsen, J; Nelson, C; Nelson, T; Neu, C; Neubauer, M S; Newman-Holmes, C; Nicollerat, A-S; Nigmanov, T; Nodulman, L; Oesterberg, K; Ogawa, T; Oh, S; Oh, Y D; Ohsugi, T; Okusawa, T; Oldeman, R; Orava, R; Orejudos, W; Pagliarone, C; Palmonari, F; Paoletti, R; Papadimitriou, V; Pashapour, S; Patrick, J

2004-07-16

197

The Network Architecture of the Connection Machine CM5  

Microsoft Academic Search

The Connection Machine Model CM-5 Supercomputer is a massively parallel computer system designed to offer performance inthe range of 1 teraflops (1012floating-point operations per second). The CM-5 obtains its high performance while offering easeof programming, flexibility, and reliability. The machine contains three communication networks: a data network, a controlnetwork, and a diagnostic network. This paper describes the organization of these

Charles Leiserson; Zahi S. Abuhamdeh; David C. Douglas; Carl R. Feynman; Mahesh N. Ganmukhi; Jeffrey V. Hill; W. Daniel Hillis; Bradley C. Kuszmaul; Margaret A. St. Pierre; David S. Wells; Monica C. Wong; Shaw-wen Yang; Robert Zak

1994-01-01

198

The Network Architecture of the Connection Machine CM5  

Microsoft Academic Search

Abstract: The Connection Machine Model CM-5 Supercomputer is a massively parallel computer system designed to offer performance inthe range of 1 teraflops (10floating-point operations per second). The CM-5 obtains its high performance while offering easeof programming, flexibility, and reliability. The machine contains three communication networks: a data network, a controlnetwork, and a diagnostic network. This paper describes the organization of

Charles E. Leiserson; Zahi S. Abuhamdeh; David C. Douglas; Carl R. Feynman; Mahesh N. Ganmukhi; Jeffrey V. Hill; W. Daniel Hillis; Bradley C. Kuszmaul; Margaret A. St. Pierre; David S. Wells; Monica C. Wong-chan; Shaw-wen Yang; Robert Zak

1996-01-01

199

Sphingosine 1-Phosphate (S1P) Receptors 1 and 2 Coordinately Induce Mesenchymal Cell Migration through S1P Activation of Complementary Kinase Pathways*  

PubMed Central

Normal bone turnover requires tight coupling of bone resorption and bone formation to preserve bone quantity and structure. With aging and during several pathological conditions, this coupling breaks down, leading to either net bone loss or excess bone formation. To preserve or restore normal bone metabolism, it is crucial to determine the mechanisms by which osteoclasts and osteoblast precursors interact and contribute to coupling. We showed that osteoclasts produce the chemokine sphingosine 1-phosphate (S1P), which stimulates osteoblast migration. Thus, osteoclast-derived S1P may recruit osteoblasts to sites of bone resorption as an initial step in replacing lost bone. In this study we investigated the mechanisms by which S1P stimulates mesenchymal (skeletal) cell chemotaxis. S1P treatment of mesenchymal (skeletal) cells activated RhoA GTPase, but this small G protein did not contribute to migration. Rather, two S1P receptors, S1PR1 and S1PR2, coordinately promoted migration through activation of the JAK/STAT3 and FAK/PI3K/AKT signaling pathways, respectively. These data demonstrate that the chemokine S1P couples bone formation to bone resorption through activation of kinase signaling pathways.

Quint, Patrick; Ruan, Ming; Pederson, Larry; Kassem, Moustapha; Westendorf, Jennifer J.; Khosla, Sundeep; Oursler, Merry Jo

2013-01-01

200

Sphingosine 1-Phosphate induces filopodia formation through S1P2R activation of ERM proteins  

PubMed Central

Previously we demonstrated that the sphingolipids ceramide and sphingosine 1-phosphate (S1P) regulate phosphorylation of the ERM family of cytoskeletal proteins [1]. Herein, we show that exogenously applied or endogenously generated S1P (in a sphingosine kinase-dependent manner) result in significant increases in phosphorylation of ERM proteins as well as filopodia formation. Utilizing phosphomimetic and non-phosphorylatable ezrin mutants, we show that the S1P-induced cytoskeletal protrusions are dependent on ERM phosphorylation. Employing various pharmacological S1P receptor agonists and antagonists, along with small interfering RNA techniques and genetic knockout approaches, we identify the S1P Receptor 2 (S1P2R) as the specific and necessary receptor to induce phosphorylation of ERM proteins and subsequent filopodia formation. Taken together, the results demonstrate a novel mechanism by which S1P regulates cellular architecture that requires S1P2R and subsequent phosphorylation of ERM proteins.

Gandy, K. Alexa Orr; Canals, Daniel; Adada, Mohamad; Wada, Masayuki; Roddy, Patrick; Snider, Ashley J.; Hannun, Yusuf A.; Obeid, Lina M.

2013-01-01

201

Comparative analysis of the vibrational structure of the absorption spectra of acrolein in the excited ( S 1) electronic state  

NASA Astrophysics Data System (ADS)

The assignments of absorption bands of the vibrational structure of the UV spectrum are compared with the assignments of bands obtained by the CRDS method in a supersonic jet from the time of laser radiation damping for the trans isomer of acrolein in the excited ( S 1) electronic state. The ?00 trans = 25861 cm-1 values and fundamental frequencies, including torsional vibration frequency, obtained by the two methods were found to coincide in the excited electronic state ( S 1) for this isomer. The assignments of several absorption bands of the vibrational structure of the spectrum obtained by the CRDS method were changed. Changes in the assignment of (0-v') transition bands of the torsional vibration of the trans isomer in the Deslandres table from the ?00 trans trans origin allowed the table to be extended to high quantum numbers v'. The torsional vibration frequencies up to v' = 5 were found to be close to the frequencies found by analyzing the vibrational structure of the UV spectrum and calculated quantum-mechanically. The coincidence of the barrier to internal rotation (the cis-trans transition) in the one-dimensional model with that calculated quantum-mechanically using the two-dimensional model corresponds to a planar structure of the acrolein molecule in the excited ( S 1) electronic state.

Koroleva, L. A.; Tyulin, V. I.; Matveev, V. K.; Pentin, Yu. A.

2012-04-01

202

Moesin Controls Clathrin-Mediated S1PR1 Internalization in T Cells  

PubMed Central

The lipid mediator sphingosine 1-phosphate (S1P) regulates a wide range of cellular activities, including vascular maturation, angiogenesis, and immune-cell trafficking. Among the five known receptors for S1P (S1PR1-S1PR5), S1PR1 is a critical regulator of lymphocyte trafficking: its signaling is required for lymphocyte egress from lymphoid organs, while its down-modulation by agonist-induced internalization is a prerequisite for lymphocyte entry into lymphoid organs from the bloodstream. Despite the importance of S1PR1 down-regulation in determining lymphocyte behavior, the molecular mechanism of its internalization in lymphocytes has not been defined. Here we show that agonist-induced S1PR1 internalization in T cells occurs via clathrin-mediated endocytosis and is regulated by moesin, an ezrin-radixin-moesin (ERM) family member. In S1P-stimulated T cells, S1PR1 relocalized within clathrin-coated vesicles (CCVs) and early endosomes, and S1PR1 internalization was blocked when clathrin was pharmacologically inhibited. Stimulating moesin-deficient T cells with S1P failed to induce S1PR1 internalization and CCV formation. Furthermore, treating moesin-deficient mice with FTY720, an S1P receptor agonist known to internalize S1PR1, caused delayed lymphopenia, and lymphocytes isolated from FTY720-treated moesin-deficient mice still responded to S1P ex vivo in chemotaxis assays. These results reveal a novel role for moesin in regulating clathrin-dependent S1PR1 internalization through CCV formation.

Nomachi, Akira; Yoshinaga, Masanori; Liu, Jaron; Kanchanawong, Pakorn; Tohyama, Kiyoshi; Thumkeo, Dean; Watanabe, Takeshi; Narumiya, Shuh; Hirata, Takako

2013-01-01

203

Lefschetz fibrations, complex structures and Seifert fibrations on S^1 X M^3  

Microsoft Academic Search

We consider product 4--manifolds S^1 X M, where M is a closed, connected and oriented 3-manifold. We prove that if S^1 X M admits a complex structure or a Lefschetz or Seifert fibration, then the following statement is true: S^1 X M admits a symplectic structure if and only if M fibers over S^1, under the additional assumption that M

Tolga Etgu; Tolga Etg

2001-01-01

204

Chondrules in the Murray CM2 meteorite and compositional differences between CM-CO and ordinary chondrite chondrules  

NASA Astrophysics Data System (ADS)

Thirteen of the least aqueously altered chondrules in Murray (CM2) were analyzed for bulk compositions, by means of a broad beam electron microprobe, to explore the compositional differences between the CM-CO, and the ordinary chondrite OC chondrules. The CO chondrules are richer in refractory lithophiles and poorer in Cr, Mn, and volatile lithophiles than the OC chondrules; much lower refractory lithophile abundances in CM chondrules resulted from aqueous alteration. Evidence is found for two important lithophile precursor components of CM-CO chondrite chondrules: (1) pyroxene- and refractory-rich, FeO-poor, and (2) olivine-rich, refractoryand FeO-poor. It is suggested that the pyroxene- and refractory-rich, FeO-poor lithophile precursor component has formed by an incomplete evaporation of presolar silicates that brought these materials into the enstatite stability field.

Rubin, A. E.; Wasson, J. T.

1986-02-01

205

Large endoscopic mucosal resection for colorectal tumors exceeding 4 cm  

PubMed Central

AIM: To evaluate the feasibility and the outcome of endoscopic mucosal resection (EMR) for large colorectal tumors exceeding 4 cm (LCRT) undergoing piecemeal resection. METHODS: From January 2005 to April 2008, 146 digestive tumors larger than 2 cm were removed with the EMR technique in our department. Of these, 34 tumors were larger than 4 cm and piecemeal resection was carried out on 26 colorectal tumors. The mean age of the patients was 71 years. The mean follow-up duration was 12 mo. RESULTS: LCRTs were located in the rectum, left colon, transverse colon and right colon in 58%, 15%, 4% and 23% of cases, respectively. All were sessile tumors larger than 4 cm with a mean size of 4.9 cm (4-10 cm). According to the Paris classification, 34% of the tumors were type?Is, 58% type IIa, 4% type IIb and 4% type IIc. Pathological examination showed tubulous adenoma in 31%, tubulo-villous adenoma in 27%, villous adenoma in 42%, high-grade dysplasia in 38%, in situ carcinoma in 19% of the cases and mucosal carcinoma (m2) in 8% of the cases. The two cases (7.7%) of procedural bleeding that occurred were managed endoscopically and one small perforation was treated with clips. During follow-up, recurrence of the tumor occurred in three patients (12%), three of whom received endoscopic treatment. CONCLUSION: EMR for tumors larger than 4 cm is a safe and effective procedure that could compete with endoscopic submucosal dissection, despite providing incomplete histological assessment.

Soune, Philippe Ah; Menard, Charles; Salah, Ezzedine; Desjeux, Ariadne; Grimaud, Jean-Charles; Barthet, Marc

2010-01-01

206

Measurement of the WW production cross section in pp collisions at square root[s]=1.96 TeV.  

PubMed

We present a measurement of the W boson pair-production cross section in pp collisions at a center-of-mass energy of sqrt[s]=1.96 TeV. The data, collected with the Run II D0 detector at Fermilab, correspond to an integrated luminosity of 224-252 pb(-1) depending on the final state (ee, emu, or mumu). We observe 25 candidates with a background expectation of 8.1+/-0.6(stat)+/-0.6(syst)+/-0.5(lum) events. The probability for an upward fluctuation of the background to produce the observed signal is 2.3x10(-7), equivalent to 5.2 standard deviations. The measurement yields a cross section of 13.8(+4.3)(-3.8)(stat)+1.2-0.9(syst)+/-0.9(lum) pb, in agreement with predictions from the standard model. PMID:15904132

Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Agelou, M; Agram, J-L; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Anderson, S; Andrieu, B; Arnoud, Y; Askew, A; Asman, B; Atramentov, O; Autermann, C; Avila, C; Badaud, F; Baden, A; Baldin, B; Balm, P W; Banerjee, S; Barberis, E; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Beauceron, S; Begel, M; Bellavance, A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Blumenschein, U; Boehnlein, A; Boeriu, O; Bolton, T A; Borcherding, F; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burnett, T H; Busato, E; Butler, J M; Bystricky, J; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chapin, D; Charles, F; Cheu, E; Chevalier, L; Cho, D K; Choi, S; Christiansen, T; Christofek, L; Claes, D; Clément, B; Clément, C; Coadou, Y; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Coss, J; Cothenet, A; Cousinou, M-C; Crépé-Renaudin, S; Cristetiu, M; Cummings, M A C; Cutts, D; da Motta, H; Davies, B; Davies, G; Davis, G A; De, K; de Jong, P; de Jong, S J; De La Cruz-Burelo, E; De Oliveria Martins, C; Dean, S; Déliot, F; Delsart, P A; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doidge, M; Dong, H; Doulas, S; Duflot, L; Dugad, S R; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Eltzroth, J T; Elvira, V D; Eno, S; Ermolov, P; Eroshin, O V; Estrada, J; Evans, D; Evans, H; Evdokimov, A; Evdokimov, V N; Fast, J; Fatakia, S N; Feligioni, L; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Freeman, W; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Garcia, C; Garcia-Bellido, A; Gardner, J; Gavrilov, V; Gay, P; Gelé, D; Gelhaus, R; Genser, K; Gerber, C E; Gershtein, Y; Ginther, G; Golling, T; Gómez, B; Gounder, K; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Gris, Ph; Grivaz, J-F; Groer, L; Grünendahl, S; Grünewald, M W; Gurzhiev, S N; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Hagopian, S; Hall, I; Hall, R E; Han, C; Han, L; Hanagaki, K; Harder, K; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hong, S J; Hooper, R; Houben, P; Hu, Y; Huang, J; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jain, V; Jakobs, K; Jenkins, A; Jesik, R; Johns, K; Johnson, M; Jonckheere, A; Jonsson, P; Jöstlein, H; Juste, A; Kado, M M; Käfer, D; Kahl, W; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J; Karmanov, D; Kasper, J; Kau, D; Kehoe, R; Kermiche, S; Kesisoglou, S; Khanov, A; Kharchilava, A; Kharzheev, Y M; Kim, K H; Klima, B; Klute, M; Kohli, J M; Kopal, M; Korablev, V M; Kotcher, J; Kothari, B; Koubarovsky, A; Kozelov, A V; Kozminski, J; Krzywdzinski, S; Kuleshov, S; Kulik, Y; Kunori, S; Kupco, A; Kurca, T; Lager, S; Lahrichi, N; Landsberg, G; Lazoflores, J; Le Bihan, A-C; Lebrun, P; Lee, S W; Lee, W M; Leflat, A; Lehner, F; Leonidopoulos, C; Lewis, P; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linn, S L; Linnemann, J; Lipaev, V V; Lipton, R; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Lubatti, H J; Lueking, L; Lynker, M; Lyon, A L; Maciel, A K A; Madaras, R J; Mättig, P; Magerkurth, A; Magnan, A-M; Makovec, N; Mal, P K; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martens, M; Mattingly, S E K; Mayorov, A A; McCarthy, R; McCroskey, R; Meder, D; Melanson, H L; Melnitchouk, A; Merkin, M; Merritt, K W; Meyer, A; Miettinen, H; Mihalcea, D; Mitrevski, J; Mokhov, N; Molina, J; Mondal, N K; Montgomery, H E; Moore, R W; Muanza, G S; Mulders, M; Mutaf, Y D; Nagy, E; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Nelson, S; Neustroev, P; Noeding, C; Nomerotski, A; Novaes, S F; Nunnemann, T; Nurse, E; O'Dell, V; O'Neil, D C; Oguri, V; Oliveira, N; Oshima, N; Otero y Garzón, G J; Padley, P; Parashar, N; Park, J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Perea, P M; Perez, E; Peters, O; Pétroff, P; Petteni, M; Phaf, L; Piegaia, R; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pope, B G; Prado da Silva, W L; Prosper, H B; Protopopescu, S; Przybycien, M B; Qian, J; Quadt, A; Quinn, B; Rani, K J; Rapidis, P A; Ratoff, P N; Reay, N W; Reucroft, S; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Royon, C; Rubinov, P; Ruchti, R; Sajot, G; Sánchez-Hernández, A; Sanders, M P

2005-04-22

207

Maribo—A new CM fall from Denmark  

NASA Astrophysics Data System (ADS)

Maribo is a new Danish CM chondrite, which fell on January 17, 2009, at 19:08:28 CET. The fall was observed by many eye witnesses and recorded by a surveillance camera, an all sky camera, a few seismic stations, and by meteor radar observatories in Germany. A single fragment of Maribo with a dry weight of 25.8 g was found on March 4, 2009. The coarse-grained components in Maribo include chondrules, fine-grained olivine aggregates, large isolated lithic clasts, metals, and mineral fragments (often olivine), and rare Ca,Al-rich inclusions. The components are typically rimmed by fine-grained dust mantles. The matrix includes abundant dust rimmed fragments of tochilinite with a layered, fishbone-like texture, tochilinite-cronstedtite intergrowths, sulfides, metals, and carbonates often intergrown with tochilinite. The oxygen isotopic composition: (?17O = -1.27‰; ?18O = 4.96‰; ?17O = -3.85‰) plots at the edge of the CM field, close to the CCAM line. The very low ?17O and the presence of unaltered components suggest that Maribo is among the least altered CM chondrites. The bulk chemistry of Maribo is typical of CM chondrites. Trapped noble gases are similar in abundance and isotopic composition to other CM chondrites, stepwise heating data indicating the presence of gas components hosted by presolar diamond and silicon carbide. The organics in Maribo include components also seen in Murchison as well as nitrogen-rich components unique to Maribo.

Haack, Henning; Grau, Thomas; Bischoff, Addi; Horstmann, Marian; Wasson, John; Sørensen, Anton; Laubenstein, Matthias; Ott, Ulrich; Palme, Herbert; Gellissen, Marko; Greenwood, Richard C.; Pearson, Victoria K.; Franchi, Ian A.; Gabelica, Zelimir; Schmitt-Kopplin, Philippe

2012-01-01

208

S-1 plus oxaliplatin vs. S-1 as first-line treatment in patients with previously untreated advanced gastric cancer: a randomized phase II study.  

PubMed

This randomized phase II study was performed to compare the efficacy and safety of oxaliplatin combined with S-1 (OXS regimen) with S-1 alone in the management of advanced gastric cancer (AGC). Ninety-four patients were 1:1 randomly assigned to S-1 on days 1-14 of a 3-week cycle or S-1 on days 1-14 plus oxaliplatin (130 mg/m(2) i.v.) on day 1 of the 3-week cycle. S-1 was orally administered in a fixed quantity according to body surface area. The median survival time with OXS versus S-1 monotherapy was 14·0 versus 11·0 months (P?=?0·03), progression-free survival was 6·5 versus 4·0 months (P?=?0·02), and the 1-year survival rate was 63·8% versus 48·9%, respectively. The response rate was significantly higher for OXS than for S-1 monotherapy (51·1% vs. 27·7%, P?=?0·03). OXS was well tolerated with no treatment-related death. In conclusion, the OXS regimen evidenced a relatively high efficacy and was well tolerated as a first-line therapy for AGC patients. PMID:24621155

Lu, Yiming; Liu, Zanchao; Zhang, Jun

2014-06-01

209

Detection of anti-preS1 antibodies for recovery of hepatitis B patients by immunoassay  

Microsoft Academic Search

AIM: To establish a convenient immunoassay method based on recombinant antigen preS1(21-119aa) to detect anti-preS1 antibodies and evaluate the clinical significance of antibodies in hepatitis B. METHODS: The expression plasmid pET-28a-preS1 was constructed, and a large quantity of preS1(21-119aa) fragment of the large HBsAg protein was obtained. The preS1 fragment purified by Ni2+-IDA affinity chromatography was used as coated antigen

Jun Wei; Yu-Qin Wang; Zhi-Meng Lu; Guang-Di Li; Yuan Wang; Zu-Chuan Zhang

2002-01-01

210

High-level expression of human ? s1 -casein in Escherichia coli  

Microsoft Academic Search

Human ?s1-casein was expressed efficiently in Escherichia coli. The overproduced recombinant human a ?s1-casein was about 25% of the total cell protein. Two different vectors were constructed to express Met-?s1-casein and Met-?s1-casein with a His-affinity tag at the C-terminus. Recombinant Met-s1-casein with a His-affinity tag was purified to homogeneity using Ni-nitrilotriacetic acid resin. N-terminal sequence of the first 10 amino

Y. K. Kim; B. H. Chung; S. Yoon; K.-K. Lee; B. Lönnerdal; D.-Y. Yu

1997-01-01

211

The Clinically-tested S1P Receptor Agonists, FTY720 and BAF312, Demonstrate Subtype-Specific Bradycardia (S1P1) and Hypertension (S1P3) in Rat  

PubMed Central

Sphingosine-1-phospate (S1P) and S1P receptor agonists elicit mechanism-based effects on cardiovascular function in vivo. Indeed, FTY720 (non-selective S1PX receptor agonist) produces modest hypertension in patients (2–3 mmHg in 1-yr trial) as well as acute bradycardia independent of changes in blood pressure. However, the precise receptor subtypes responsible is controversial, likely dependent upon the cardiovascular response in question (e.g. bradycardia, hypertension), and perhaps even species-dependent since functional differences in rodent, rabbit, and human have been suggested. Thus, we characterized the S1P receptor subtype specificity for each compound in vitro and, in vivo, the cardiovascular effects of FTY720 and the more selective S1P1,5 agonist, BAF312, were tested during acute i.v. infusion in anesthetized rats and after oral administration for 10 days in telemetry-instrumented conscious rats. Acute i.v. infusion of FTY720 (0.1, 0.3, 1.0 mg/kg/20 min) or BAF312 (0.5, 1.5, 5.0 mg/kg/20 min) elicited acute bradycardia in anesthetized rats demonstrating an S1P1 mediated mechanism-of-action. However, while FTY720 (0.5, 1.5, 5.0 mg/kg/d) elicited dose-dependent hypertension after multiple days of oral administration in rat at clinically relevant plasma concentrations (24-hr mean blood pressure?=?8.4, 12.8, 16.2 mmHg above baseline vs. 3 mmHg in vehicle controls), BAF312 (0.3, 3.0, 30.0 mg/kg/d) had no significant effect on blood pressure at any dose tested suggesting that hypertension produced by FTY720 is mediated S1P3 receptors. In summary, in vitro selectivity results in combination with studies performed in anesthetized and conscious rats administered two clinically tested S1P agonists, FTY720 or BAF312, suggest that S1P1 receptors mediate bradycardia while hypertension is mediated by S1P3 receptor activation.

Fryer, Ryan M.; Muthukumarana, Akalushi; Harrison, Paul C.; Nodop Mazurek, Suzanne; Chen, Rong Rhonda; Harrington, Kyle E.; Dinallo, Roger M.; Horan, Joshua C.; Patnaude, Lori; Modis, Louise K.; Reinhart, Glenn A.

2012-01-01

212

A survey on readiness and needs regarding the transition from ICD-9-CM to ICD-10-CM.  

PubMed

The New York State Congenital Malformations Registry (CMR) conducted a Web-based survey to assess reporting hospitals readiness and needs with regards to the transition from the ICD-9-CM to ICD-10-CM for diagnoses and ICD-10-PCS for procedure coding system (PCS). The survey contains 8 questions focusing on the transition to collect information about case reporting methods, anticipated plan and date for the transition, and the needs from the CMR for the process. In September 2012, a link to the Web-based survey was sent to all 158 CMR reporting hospitals requesting completion of the online survey. By October 31, 2012, 91 (60 percent) out of 158 reporting hospitals completed the survey. For the question "When will your facility be ready to report to the CMR using the ICD-10 coding system?", a majority (71 percent) of the respondents answered October 1, 2014. With regard to the method they plan to use for converting from ICD-9-CM to ICD-10-CM/PCS, 51 percent will rely on a crosswalk provided by vendors and 7 percent will use the general equivalence mapping method. Nearly half (45 percent) of the respondents were interested in implementing a dual reporting system (accepting both ICD-9-CM and ICD-10-CM/ PCS by the CMR). For the question, "What specific information would you like the Congenital Malformations Registry to provide in regards to reporting to this registry using ICD-10?", 30% of the respondents requested a list of reportable ICD-10-CM/PCS codes and related descriptions, 10 percent requested an ICD-9-CM to ICD-10-CM/PCS crosswalk, and 19 percent requested keeping them updated with information about the transition and implementation of ICD-10-CM/PCS. Among the respondents who provided comments at the end of the survey, more than half (55 percent) stated that they are in the process of transition and 27 percent expressed thanks and appreciation for CMR's leading effort on the transition project. This online survey enabled the CMR staff to assess readiness and identify the needs of the hospitals regarding the transition. This information will help the CMR with appropriate planning for our own transition and enable us to meet the needs of hospital reporters PMID:24400373

Wang, Ying; Tao, Zhen; Fox, Deborah; Steen, Patricia; Druschel, Charlotte M

2013-01-01

213

CM-2 Environmental/Modal Testing of SPACEHAB Racks  

NASA Technical Reports Server (NTRS)

Combined environmental/modal vibration testing has been implemented at the NASA Glenn Research Center's Structural Dynamics Laboratory. The benefits of combined vibration testing are that it facilitates test article modal characterization and vibration qualification testing. The Combustion Module-2 (CM-2) is a space experiment that will launch on shuttle mission STS-107 in the SPACEHAB Research Double Module. The CM-2 flight hardware is integrated into a SPACEHAB single and double rack. CM-2 rack-level combined vibration testing was recently completed on a shaker table to characterize the structure's modal response and verify the random vibration response. Control accelerometers and limit force gauges, located between the fixture and rack interface, were used to verify the input excitation. Results of the testing were used to verify the loads and environments for flight on the shuttles.

McNelis, Mark E.; Goodnight, Thomas W.

2001-01-01

214

CM-2 Environmental / Modal Testing of Spacehab Racks  

NASA Technical Reports Server (NTRS)

Combined environmental/modal vibration testing has been implemented at the NASA Glenn Research Center's Structural Dynamics Laboratory. The benefits of combined vibration testing are that it facilitates test article modal characterization and vibration qualification testing. The Combustion Module-2 (CM-2) is a space experiment that launches on Shuttle mission STS 107 in the SPACEHAB Research Double Module. The CM-2 flight hardware is integrated into a SPACEHAB single and double rack. CM-2 rack level combined vibration testing was recently completed on a shaker table to characterize the structure's modal response and verify the random vibration response. Control accelerometers and limit force gauges, located between the fixture and rack interface, were used to verify the input excitation. Results of the testing were used to verify the loads and environments for flight on the Shuttle.

McNelis, Mark E.; Goodnight, Thomas W.; Farkas, Michael A.

2001-01-01

215

High resolution comparative modeling with RosettaCM  

PubMed Central

We describe an improved method for comparative modeling, RosettaCM, which optimizes a physically realistic all-atom energy function over the conformational space defined by homologous structures. Given a set of sequence alignments, RosettaCM assembles topologies by recombining aligned segments in Cartesian-space and building unaligned regions de novo in torsion space. The junctions between segments are regularized using a loop-closure method combining fragment superposition with gradient-based minimization. The energies of the resulting models are optimized by all-atom refinement, and the most representative low energy model is selected. The CASP10 experiment suggests RosettaCM yields models with more accurate sidechain and backbone conformations than other methods when the sequence identity to the templates is greater than ?15%.

Song, Yifan; DiMaio, Frank; Wang, Ray Yu-Ruei; Kim, David; Miles, Chris; Brunette, TJ; Thompson, James; Baker, David

2013-01-01

216

Jet-cooled fluorescence spectra and carbonyl wagging potential energy functions of tetrahydrofuran-3-one and tetrahydrothiophen-3-one in their S 1(n,??) excited states  

NASA Astrophysics Data System (ADS)

The jet-cooled fluorescence excitation spectra of states of tetrahydrofuran-3-one and tetrahydrothiophen-3-one have been recorded and analyzed. The carbonyl inversion bands, which arise from double-minimum potential energy functions in the excited states, were fit with functions of the form V = ax4 - bx2 or V = cx2 + dexp(- fx2). The furanone was found to have an inversion barrier in the S 1(n,??) state of 1152 cm -1 (13.8 kJ mol -1) while the thiophenone has a barrier of 659 cm -1 (7.9 kJ mol -1). The two molecules have their potential energy minima for the S 1(n,??) state at carbonyl wagging angles of 26 and 20°, respectively. The results here, together with previous data for several other cyclic ketones, demonstrate that the inversion barrier increases with the ring angle strain at the ketone carbon atom.

Laane, Jaan; Sagear, Paul A.; Lee, S. N.

1997-06-01

217

S1P lyase in skeletal muscle regeneration and satellite cell activation: Exposing the hidden lyase?  

PubMed Central

Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid whose actions are essential for many physiological processes including angiogenesis, lymphocyte trafficking and development. In addition, S1P serves asamuscle trophic factor that enables efficient muscle regeneration. This is due in part to S1P's ability to activate quiescent muscle stem cells called satellite cells (SCs) that are needed for muscle repair. However, the molecular mechanism by which S1P activates SCs has not been well understood. Further, strategies for harnessing S1P signaling to recruit SCs for therapeutic benefit have been lacking. S1P is irreversibly catabolized by S1P lyase (SPL), a highly conserved enzyme that catalyzes the cleavage of S1P at carbon bond C2–3, resulting in formation of hexadecenal and ethanolamine-phosphate. SPL enhances apoptosis through substrate- and product-dependent events, thereby regulating cellular responses to chemotherapy, radiation and ischemia. SPL is undetectable in resting murine skeletal muscle. However, we recently found that SPL is dynamically upregulated in skeletal muscle after injury. SPL upregulation occurred in the context of a tightly orchestrated genetic program that resulted in a transient S1P signal in response to muscle injury. S1P activated quiescent SCs via a sphingosine-1-phosphate receptor 2 (S1P2)/signal transducer and activator of transcription 3 (STAT3)-dependent pathway, thereby facilitating skeletal muscle regeneration. Mdx mice, which serve as a model for muscular dystrophy (MD), exhibited skeletal muscle SPL upregulation and S1P deficiency. Pharmacological SPL inhibition raised skeletal muscle S1P levels, enhanced SC recruitment and improved mdx skeletal muscle regeneration. These findings reveal how S1P can activate SCs and indicate that SPL suppression may provide a therapeutic strategy for myopathies. This article is part of a Special Issue entitled Advances in Lysophospholipid Research.

Saba, Julie D.; de la Garza-Rodea, Anabel S.

2013-01-01

218

Cross section for {sup 246}Cm subbarrier fission  

SciTech Connect

The cross section for {sup 246}Cm fission induced by neutrons of energy in the range 0.1 eV-20 keV was measured by the neutron lead slowing-down spectrometer (LSDS-100) of the Institute for Nuclear Research (INR, Russian Academy of Sciences, Moscow). The parameters of the resonance area and of the fission width were evaluated for several low-lying s-wave neutron resonances. The parameters of the intermediate structure in the cross section for the subbarrier fusion of {sup 246}Cm nuclei were found. The results obtained in this way were compared with available experimental data and with recommended evaluated data.

Alekseev, A. A.; Bergman, A. A.; Berlev, A. I.; Koptelov, E. A. [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation); Samylin, B. F.; Trufanov, A. M.; Fursov, B. I.; Shorin, V. S., E-mail: shorin@ippe.r [Institute for Physics and Power Engineering (Russian Federation)

2010-10-15

219

A search for 18-cm OH emission from Comet Crommelin  

NASA Astrophysics Data System (ADS)

The Arecibo radiotelescope was used to scan for OH 18-cm line emissions from the Comet Crommelin as a trial for 3 arcsec resolution observations of Halley's Comet. The instrument was centered on the 1665 and 1667 MHz bands during intervals in January and February 1984. No detection of the OH 1665 and 1667 MHz lines was made above a 3-sigma limit of 9 mJy; and no detection of continuum emission at 18 cm was made above a 3-sigma level of 5 mJy.

Deich, W. T. S.; Cordes, J. M.; Terzian, Y.

1985-02-01

220

5200 cycle of an 8-cm diameter Hg ion thruster  

NASA Technical Reports Server (NTRS)

An accelerated cycle test was conducted in which an 8-cm Engineering Model Thruster (EMT) prototype successfully completed 5200 on-off cycles and a total of more than 1300 hours of thruster operation at a 4.5 mN thrust level. Cathode tip heater powers required for starting and keeper voltages remained well within acceptable limits. The discharge chamber utilization and electrical efficiency were nearly constant over the duration of the test. It is concluded that on-off cyclic operation by itself does not appreciably degrade starting capability or performance of the 8-cm EMT.

Mantenieks, M. A.; Wintucky, E. G.

1978-01-01

221

Cycle life testing of 8-cm mercury ion thruster cathodes  

NASA Technical Reports Server (NTRS)

Two main cathodes have successfully completed 2800 and 1980 cycles and three neutralizers, 3928, 3050, and 2850 cycles in ongoing cycle life tests of flight-type cathode-isolator-vaporizer and neutralizer-isolator-vaporizer assemblies for the 4.45 mN 8-cm Hg ion thruster system. Each cycle included one hour of cathode operation. Starting and operating conditions simulated those expected in a typical auxiliary propulsion mission duty cycle. The cycle life test results are presented along with results of an insert comparison test which led to the selection of a rolled foil insert type for the 8-cm Engineering Model Thruster cathodes.

Wintucky, E. G.

1976-01-01

222

Precise measurements of primordial power spectrum with 21 cm fluctuations  

NASA Astrophysics Data System (ADS)

We discuss the issue of how precisely we can measure the primordial power spectrum by using future observations of 21 cm fluctuations and cosmic microwave background (CMB). For this purpose, we investigate projected constraints on the quantities characterizing primordial power spectrum: the spectral index ns, its running ?s and even its higher order running ?s. We show that future 21 cm observations in combinations with CMB would accurately measure above mentioned observables of primordial power spectrum. We also discuss its implications to some explicit inflationary models.

Kohri, Kazunori; Oyama, Yoshihiko; Sekiguchi, Toyokazu; Takahashi, Tomo

2013-10-01

223

21-cm background anisotropies can discern primordial non-Gaussianity.  

PubMed

The non-Gaussianity of initial perturbations provides information on the mechanism that generated primordial density fluctuations. We find that 21-cm background anisotropies due to inhomogeneous neutral hydrogen distribution prior to reionization captures information on primordial non-Gaussianity better than a high-resolution cosmic microwave background anisotropy map. An all-sky 21-cm experiment over the frequency range from 14 to 40 MHz with angular information out to a multipole of 10(5) can limit the primordial non-Gaussianity parameter f(NL) <, similar 0.01. PMID:17280413

Cooray, Asantha

2006-12-31

224

Theory of the temperature dependence of the NMR shift of intermediate spin (S = 1) four-coordinate ferrous porphyrins  

SciTech Connect

The theory of the NMR shift (pseudocontact and contact) for the intermediate spin state (S = 1) of four-coordinate ferrous porphyrins in developed for the general case of axial symmetry. The theory is then fitted to temperature data for the {sup 1}H NMR shifts of Fe(OEP) (iron (II)), Fe(OEC) (iron(II)), and Fe(TPP). It is also fitted to temperature data for the magnetic susceptibility and magnetic anisotropy of solid Fe(TPP) and Fe(PC) ((phthalocyaninato)iron(II)). The theory assumes the ground state to be a {sup 3}A{sub 2g} state that is spin-orbit coupled with the {sup 3}E{sub g} state at energy {Delta}. In low symmetry the {sup 3}E{sub g} state is split by the energy {delta}. In solution {Delta} = 600 cm {sup {minus}1} for Fe(OEC) and Fe(OEC) and {approximately} 1000 cm {sup {minus}1} for Fe(TPP). {Delta} is reduced to 400 cm {sup {minus}1} in solid Fe(TPP) and is {minus}900 cm{sup {minus}1} in solid Fe(PC) ({sup 3}E{sub g} ground state). In solution {delta} = {minus}700 cm{sup {minus}1} in Fe(OEC). In Fe(OEP) and Fe(OEC), enough experimental data are available to allow the determination of the geometrical factors for the pseudocontact shift of the methyl resonances from the NMR shifts. The theory is successful in explaining the temperature dependence of the pseudocontact shifts and magnetic susceptibilities but does not fully account for the temperature behavior of the contact shifts.

McGarvey, B.R. (Univ. of Windsor, Ontario (Canada))

1988-12-14

225

Operation of a Five-Stage 40,000-CM(2)-Area Insulator Stack at 158 KV/CM  

SciTech Connect

We have demonstrated successful operation of a 3.35- m-diameter insulator stack at 158 kV/cm on five consecutive Z-accelerator shots. The stack consisted of five +45°-profile 5.715-cm-thick cross-linked-polystyrene (Rexolite- 1422) insulator rings, and four anodized- aluminum grading rings shaped to reduce the field at cathode triple junctions. The width of the voltage pulse at 89% of peak was 32 ns. We compare this result to a new empirical flashover relation developed from previous small-insulator experiments conducted with flat unanodized electrodes. The relation predicts a 50% flashover probability for a Rexolite insulator during an applied voltage pulse when Emaxe-0.27/d(teffC)1/10 = 224, where Emax is the peak mean electric field (kV/cm), d is the insulator thickness (cm), teff is the effective pulse width (ps), and C is the insulator circumference (cm). We find the Z stack can be operated at a stress at least 19% higher than predicted. This result, and previous experiments conducted by Vogtlin, suggest anodized electrodes with geometries that reduce the field at both anode and cathode triple junctions would improve the flashover strength of +45° insulators.

Anderson R.A.; Clark, Robert E.; Corcoran, P.A.; Douglas, John W.; Gilliland, T.L.; Horry, M.L.; Hughes, Thomas P.; Ives, H.C.; Long, F.W.; Martin, T.H.; McDaniel, D.H.; Milton, Osborne; Mostrom, Michael A.; Seamen, J.F.; Shoup, R.W.; Smith, I.D.; Smith, J.W.; Spielman, R.B.; Struve, K.W.; Stygar, W.A.; Vogtlin, George E.; Wagoner, T.C.; Yamamoto, Osamu

1999-06-30

226

Cosmic (Super)String Constraints from 21 cm Radiation  

Microsoft Academic Search

We calculate the contribution of cosmic strings arising from a phase transition in the early Universe, or cosmic superstrings arising from brane inflation, to the cosmic 21 cm power spectrum at redshifts z{>=}30. Future experiments can exploit this effect to constrain the cosmic string tension G and probe virtually the entire brane inflation model space allowed by current observations. Although

Benjamin D. Wandelt; Rishi Khatri

2008-01-01

227

Cosmic (Super)String Constraints from 21cm Radiation  

Microsoft Academic Search

We calculate the contribution of cosmic strings arising from a phase transition in the early Universe, or cosmic superstrings arising from brane inflation, to the cosmic 21 cm power spectrum at redshifts z>=30. Future experiments can exploit this effect to constrain the cosmic string tension Gmu and probe virtually the entire brane inflation model space allowed by current observations. Although

Rishi Khatri; Benjamin D. Wandelt

2008-01-01

228

Testing of the Kuiper Airborne Observatory 91-cm Telescope.  

National Technical Information Service (NTIS)

The 91 cm telescope of the Kuiper Airborne Observatory was tested for optical figure errors in the surface of the mirrors and misalignment of the optical components. When the present set of optical components are installed in the telescope in proper align...

R. E. Parks

1979-01-01

229

Fractionation of Serum Protein by cm-Cellulose Column.  

National Technical Information Service (NTIS)

Employing CM-cellulose column, serum protein is eluted with pH 5.4 acetate buffer, and the composition of each fraction is identified by the paper electrophoresis of each fraction and the comparison of its chromatogram with that of standard albumin and gl...

Y. Tanaka Y. Iwashita Y. Nakakima T. Kohi S. Noguchi

1966-01-01

230

Alveolar Gas - Mac 10.7 Version  

NSDL National Science Digital Library

Alveolar Gas is a computer program that lets you study some of the physiological factors that affect the composition of alveolar and expired gases. Such factors include dead space, tidal volume, the frequency of breathing, and the rates of oxygen consumption and carbon dioxide production. A worksheet is included.

2012-09-20

231

Revised Final DOE10-7-13  

SciTech Connect

The project goal was reduction of energy consumption on a group of multi-use buildings. The initial step was to assess the group of buildings and define a set of Energy Conservation Measures (ECM?s) that would return an average energy consumption savings of thirty percent. The assessments defined deficiencies in systems from building envelope to interior lighting. Corrections for the deficiencies were addressed through ECM?s that included: high efficiency lighting, occupancy sensors, programmable thermostats, HVAC upgrades, insulation upgrades, as well as a solar thermal installation to reduce propane consumption. ECM?s were recommended based on calculated energy savings. ECM implementation was performed using licensed professionals across multiple disciplines. Electricians installed new lighting and set up occupancy sensors while plumbers implemented low flow fixtures and insulated water heater systems. A general contractor sealed and repaired building envelopes while overseeing other disciplines. Final energy consumption reductions will exceed thirty percent across nine buildings

Gilbreath, Bob; Maples, Manuel G

2013-10-07

232

A 14 cm times 36 cm volume negative ion source producing multi-ampere H sup minus ion beams  

SciTech Connect

A large volume negative ion source, which has a newly devised magnetic filter called a PG filter, was designed and tested. The PG filter produces a uniform magnetic filter field over a large extraction area of 14{times}36 cm{sup 2} by flowing a high current through the plasma grid itself. By optimizing the filter strength, we succeeded to produce 3.4-A 75-keV negative hydrogen ion beams for 50 ms from 253 apertures of 11.3 mm diam with an average current H{sup {minus}} density of 13 mA/cm{sup 2}.

Hanada, M.; Inoue, T.; Kojima, H.; Matsuda, Y.; Ohara, Y.; Okumura, Y.; Watanabe, K.; Seki, M. (Japan Atomic Energy Research Institute, Naka-machi, Naka-gun, Ibaraki-ken, 311-01, Japan (JP))

1990-01-01

233

Limits on variations in fundamental constants from 21-cm and ultraviolet Quasar absorption lines.  

PubMed

Quasar absorption spectra at 21-cm and UV rest wavelengths are used to estimate the time variation of x [triple-bond] alpha(2)g(p)mu, where alpha is the fine structure constant, g(p) the proton g factor, and m(e)/m(p) [triple-bond] mu the electron/proton mass ratio. Over a redshift range 0.24 < or = zeta(abs) < or = 2.04, (Deltax/x)(weighted)(total) = (1.17 +/- 1.01) x 10(-5). A linear fit gives x/x = (-1.43 +/- 1.27) x 10(-15) yr(-1). Two previous results on varying alpha yield the strong limits Deltamu/mu = (2.31 +/- 1.03) x 10(-5) and Deltamu/mu=(1.29 +/- 1.01) x10(-5). Our sample, 8 x larger than any previous, provides the first direct estimate of the intrinsic 21-cm and UV velocity differences 6 km s(-1). PMID:16090794

Tzanavaris, P; Webb, J K; Murphy, M T; Flambaum, V V; Curran, S J

2005-07-22

234

Fourier Transform Spectroscopy of 18O-Enriched Carbonyl Sulfide from 1825 to 2700 cm -1  

NASA Astrophysics Data System (ADS)

We have measured the Fourier transform spectrum of carbonyl sulfide from 1825 to 2700 cm -1, using a sample enriched in both 18O (94.0%) and 17O (1.54%). A careful calibration yields a line-position accuracy between 1.5 and 3.0 10 -5cm -1. We have observed and analyzed 118 infrared bands of which 93 are measured for the first time: 55 for 18O 12C 32S, 20 for 18O 12C 34S, 11 for 18O 12C 33S, 1 for 18O 12C 36S, 12 for 17O 12C 32S, 4 for 17O 12C 34S, 2 for 17O 12C 33S, and 13 for 18O 13C 32S. Intensities are also reported and analyzed for all those bands. The intensity accuracy is better than 10%, and the precision of approximately 1% allows us to determine some Herman-Wallis coefficients.

Strugariu, T.; Na??m, S.; Fayt, A.; Bredohl, H.; Blavier, J.-F.; Dubois, I.

1998-06-01

235

Relaxation Mechanism of ?-Carotene from S2 (1Bu(+)) State to S1 (2Ag(-)) State: Femtosecond Time-Resolved Near-IR Absorption and Stimulated Resonance Raman Studies in 900-1550 nm Region.  

PubMed

Carotenoids have two major low-lying excited states, the second lowest (S2 (1Bu(+))) and the lowest (S1 (2Ag(-))) excited singlet states, both of which are suggested to be involved in the energy transfer processes in light-harvesting complexes. Studying vibrational dynamics of S2 carotenoids requires ultrafast time-resolved near-IR Raman spectroscopy, although it has much less sensitivity than visible Raman spectroscopy. In this study, the relaxation mechanism of ?-carotene from the S2 state to the S1 state is investigated by femtosecond time-resolved multiplex near-IR absorption and stimulated Raman spectroscopy. The energy gap between the S2 and S1 states is estimated to be 6780 cm(-1) from near-IR transient absorption spectra. The near-IR stimulated Raman spectrum of S2 ?-carotene show three bands at 1580, 1240, and 1050 cm(-1). When excess energy of 4000 cm(-1) is added, the S1 C?C stretch band shows a large upshift with a time constant of 0.2 ps. The fast upshift is explained by a model that excess energy generated by internal conversion from the S2 state to the S1 state is selectively accepted by one of the vibronic levels of the S1 state and is redistributed among all the vibrational modes. PMID:24844607

Takaya, Tomohisa; Iwata, Koichi

2014-06-12

236

Properties of CM-SAF's cloud products -a statistical analysis  

NASA Astrophysics Data System (ADS)

Clouds have a major impact on the earth radiation budget and contribute significantly to the state of the climate system. Additionally, the space-based retrieval of other atmospheric pa-rameters is highly influenced by clouds. Therefor it is essential to assess the strengths and limitations of the satellite-derived cloud properties as accurately as possible. This study deals with those cloud products, that are operationally generated by the EUMETSAT's Satellite Ap-plication Facility on Climate Monitoring (CM-SAF). CM-SAF uses space-based observations from geostationary Meteosat Second Generation (MSG) satellites and polar orbiting NOAA and MetOp satellites to provide satellite-derived geophysical parameter data sets suitable for climate monitoring. CM-SAF's product suite includes cloud parameters, radiation fluxes, sur-face albedo, and atmospheric water vapor, temperature and humidity profiles on a regional and partially on a global scale and thereby focuses on geophysical parameters describing the elements of the energy and water cycle. Since 2005 a threshold technique is used within the CM-SAF to derive various cloud products from satellite data, some are further estimated with an iterative look-up table approach. The properties of CM-SAF's cloud products which are cloud top variables (in here: Cloud Top Height (CTH)), Liquid Water Path (LWP), Cloud Type (CTY), Cloud Optical Thickness (COT) and Cloud Fraction (CFC) are explored and analyzed statistically. The individual products are related to each other via for example two-dimensional frequency distributions in order to verify their consistency. From these statistics average properties for certain classified types are derived, such as LWP-distributions for five different CM-SAF cloud types. Each cloud type can be characterized by an average LWP dis-tribution. Also temporal variations for the cloud properties are studied. The Cloud Top Height product for example shows strong seasonal variations, depending on latitude. Locating the maximal CTH near the equator makes it possible to easily monitor the meridional traveling of the Inter-Tropical Convergence Zone during the the seasons.

Kniffka, Anke; Lockhoff, Maarit; Hollmann, Rainer; Weber, Ralf

237

The 12 micron band of ethane: A spectral catalog from 765 cm(-1) to 900 cm(-1)  

NASA Technical Reports Server (NTRS)

The high resolution laboratory absorption spectrum of the 12 micro band of ethane gas is studied. The data were obtained using the McMath Solar Telescope 1 meter Fourier Transform interferometer at Kitt Peak National Observatory and tunable diode laser spectrometers at the University of Tennessee and NASA/Goddard Space Flight Center. Over 200 individual vibration rotation transitions were analyzed taking into account many higher order effects including torsional splitting. Line positions were reproduced to better than 0.001/cm. Both ground and upper state molecular constants were determined in the analysis. The experimental details, the analysis procedures and the results are addressed. A list of ethane transitions occurring near (14)CO2 laser lines needed for heterodyne searches for C2H6 in extraterrestrial sources is also included. A spectral catalog of the ethane nu sub g fundamental from 765/cm to 900/cm is provided. A high dispersion (1/cm 12 in.) plot of both the Kitt Peak interferometric data and a simulated spectrum with Doppler limited resolution, a table of over 8500 calculated transitions listed quantum number assignments, frequencies and intensities are provided.

Atakan, A. K.; Blass, W. E.; Brault, J. W.; Daunt, S. J.; Halsey, G. W.; Jennings, D. E.; Reuter, D. C.; Susskind, J.

1983-01-01

238

The nature of dark matter from the global high-redshift H I 21 cm signal  

NASA Astrophysics Data System (ADS)

We study the imprint of dark matter (DM) annihilation on the global 21 cm signal from the Dark Ages to Cosmic Reionization. Motivated by recent observations, we focus on three DM candidates: (i) a 10 GeV Bino-like neutralino; (ii) a 200 GeV Wino and (iii) a 1 TeV heavier particle annihilating into leptons. For each DM candidate we assume two values for the thermally averaged annihilation cross-section , the standard thermal value th = 3 × 10-26 cm3 s-1 and the maximum value allowed by WMAP7 data, max. We include the enhancement of DM annihilations due to collapsed structures, detailed estimates of energy deposition into the intergalactic medium (IGM), as well realistic prescriptions for astrophysical sources of UV and X-ray radiation. In these models, the additional heat input from DM annihilation suppresses the mean 21 cm brightness temperature offset by ?Tb ˜ a few-100 mK. In particular, the very deep ?Tb ˜ -150 mK absorption feature at ˜20 ? z ? 25 predicted by popular models of the first galaxies is considerably reduced or totally erased by some of the considered DM candidates. Such an enhancement in IGM heating could come from either DM annihilations or a stronger-than-expected astrophysical component (i.e. abundant early X-ray sources). However, we find that the two signatures are not degenerate, since the DM heating is dominated by haloes several orders of magnitude smaller than those hosting galaxies, whose fractional abundance evolves more slowly resulting in a smaller gradient: d?Tb/d? ? 4 mK MHz-1 in the range ? ˜ 60-80 MHz. The detection of such signals by future radio telescopes would be clear evidence of DM energy injection at high redshifts.

Valdés, M.; Evoli, C.; Mesinger, A.; Ferrara, A.; Yoshida, N.

2013-02-01

239

Effects of methionine-containing dipeptides on ?s1casein expression in bovine mammary epithelial cells  

Microsoft Academic Search

Effects of methionine-containing dipetides on ?s1 casein gene expression were investigated in cultured bovine mammary epithelial cells. ?s1Casein gene expression was higher in the culture added with methionylmethionine than in that with methionine. Addition of methionyllysine enhanced ?s1 casein gene expression, compared with methionine plus lysine. These results indicated that mammary epithelial cells can utilize methionine-containing dipeptides for milk protein

H. H. Wu; J. Y. Yang; K. Zhao; H. Y. Liu; Y. M. Wu; J. X. Liu

240

Engagement of the S1, S1' and S2' subsites drives efficient catalysis of peptide bond hydrolysis by the M1-family aminopeptidase from Plasmodium falciparum  

PubMed Central

The M1-family aminopeptidase PfA-M1 catalyzes the last step in the catabolism of human hemoglobin to amino acids in the Plasmodium falciparum food vacuole. In this study, the structural features of the substrate that promote efficient PfA-M1-catalyzed peptide bond hydrolysis were analyzed. X-Ala and Ala-X dipeptide substrates were employed to characterize the specificities of the enzyme's S1 and S1’ subsites. Both subsites exhibited a preference for basic and hydrophobic sidechains over polar and acidic sidechains. The relative specificity of the S1 subsite was similar over the pH range 5.5 - 7.5. Substrate P1 and P1’ residues affected both Km and kcat, revealing that sidechain-subsite interactions not only drive the formation of the Michaelis complex but also influence the rates of ensuing chemical steps. Only a small fraction of the available binding energy was exploited in interactions between substrate sidechains and the S1 and S1’ subsites, which indicates a modest level of complementarity. There was no correlation between S1 and S1’ specificities and amino acid abundance in hemoglobin. Interactions between PfA-M1 and the backbone atoms of the P1’ and P2’ residues as well as the P2’ sidechain further contributed to the catalytic efficiency of substrate hydrolysis. By demonstrating the engagement of multiple, broad-specificity subsites in PfA-M1, these studies provide insight into how this enzyme is able to efficiently generate amino acids from highly sequence-diverse di- and oligopeptides in the food vacuole.

Dalal, Seema; Ragheb, Daniel R. T.; Klemba, Michael

2012-01-01

241

21Â cm fluctuations from primordial magnetic fields  

NASA Astrophysics Data System (ADS)

Recent observations of magnetic fields in intergalactic void regions and in high redshift galaxies may indicate that large scale magnetic fields have a primordial origin. If primordial magnetic fields were present soon after the recombination epoch, they would have induced density fluctuations on the one hand and dissipated their energy into the primordial gas on the other, and thereby significantly altered the thermal history of the Universe. Here we consider both the effects and calculate the brightness temperature fluctuations of the 21 cm line using simple Monte Carlo simulations. We find that the fluctuations of the 21 cm line from the energy dissipation appear only on very small scales and those from the density fluctuations always dominate on observationally relevant angular scales.

Shiraishi, Maresuke; Tashiro, Hiroyuki; Ichiki, Kiyotomo

2014-05-01

242

21 cm cosmology in the 21st century.  

PubMed

Imaging the Universe during the first hundreds of millions of years remains one of the exciting challenges facing modern cosmology. Observations of the redshifted 21 cm line of atomic hydrogen offer the potential of opening a new window into this epoch. This will transform our understanding of the formation of the first stars and galaxies and of the thermal history of the Universe. A new generation of radio telescopes is being constructed for this purpose with the first results starting to trickle in. In this review, we detail the physics that governs the 21 cm signal and describe what might be learnt from upcoming observations. We also generalize our discussion to intensity mapping of other atomic and molecular lines. PMID:22828208

Pritchard, Jonathan R; Loeb, Abraham

2012-08-01

243

The peak 21-cm surface brightness of spiral galaxies  

NASA Astrophysics Data System (ADS)

High-resolution VLA observations of the H I emission from M 31 by Braun (1990) show a very surprising result that the peak brightness temperature of the 21-cm line is consistently higher there than anywhere in the galaxy (175 to 180 K vs 125 to 130 K for the Milky Way). It is suggested that such differences may be common among spiral galaxies, particularly those edge-on enough to have high-velocity gradients along the line of sight, caused simply by a different mixture of the warm and cool phases of H I. From 21-cm absorption observations (Dickey and Brinks, 1988) we know that M 31 has much less cool H I than the Milky Way, but about the same amount of total atomic hydrogen. Using those results, we can explain Braun's numbers with a simple radiative transfer model.

Dickey, John M.

244

Performance of the NASA 30 cm Ion Thruster  

NASA Technical Reports Server (NTRS)

A 30 cm diameter xenon ion thruster is under development at NASA to provide an ion propulsion option for missions of national interest, and is being proposed for use on the USAF/TRW Space Surveillance, Tracking and Autonomous Repositioning (SSTAR) platform to validate ion propulsion. The thruster incorporates innovations in design, materials, and fabrication techniques compared to those employed in conventional ion thrusters. Specific development efforts include thruster design optimizations, component life testing and validation, vibration testing, and performance characterizations. Under this test program, the ion thruster will be brought to engineering model development status. This paper discusses the performance and power throttling test data for the NASA 30 cm diameter xenon ion thruster over an input power envelope of 0.7 to 4.9 kW, and corresponding thruster lifetime expectations.

Patterson, Michael J.; Haag, Thomas W.; Hovan, Scot A.

1993-01-01

245

Precision measurement of cosmic magnification from 21 cm emitting galaxies  

SciTech Connect

We show how precision lensing measurements can be obtained through the lensing magnification effect in high redshift 21cm emission from galaxies. Normally, cosmic magnification measurements have been seriously complicated by galaxy clustering. With precise redshifts obtained from 21cm emission line wavelength, one can correlate galaxies at different source planes, or exclude close pairs to eliminate such contaminations. We provide forecasts for future surveys, specifically the SKA and CLAR. SKA can achieve percent precision on the dark matter power spectrum and the galaxy dark matter cross correlation power spectrum, while CLAR can measure an accurate cross correlation power spectrum. The neutral hydrogen fraction was most likely significantly higher at high redshifts, which improves the number of observed galaxies significantly, such that also CLAR can measure the dark matter lensing power spectrum. SKA can also allow precise measurement of lensing bispectrum.

Zhang, Pengjie; /Fermilab; Pen, Ue-Li; /Canadian Inst. Theor. Astrophys.

2005-04-01

246

Expression of a biologically active GFP-?(S1)-casein fusion protein in Lactococcus lactis.  

PubMed

In this study, we successfully developed a recombinant strain of Lactococcus lactis NZ9000 (NZ9000) that produced green fluorescent protein fused to ?(S1)-casein (GFP-?(S1)Cas). A modified lactic acid bacterial vector (pNZ8148#2) was constructed by inserting genes for GFP and ?(S1)-casein, a major cow's milk allergen, and the resulting vector, pNZ8148#2-GFP-?(S1)Cas, was applied to the expression of recombinant GFP-?(S1)Cas protein (rGFP-?(S1)Cas) in NZ9000. After inducing expression with nisin, the production of rGFP-?(S1)Cas was confirmed by confocal laser microscopic analysis, and the expression conditions were optimized based on fluorescent analysis and western blotting results. Moreover, the in vitro treatment of splenocytes isolated from ?-casein (?70 % ?(S)-casein)-immunized mice with rGFP-?(S1)Cas resulted in increased IL-13 mRNA expression. The observed allergic activity is indicative of the Th2-cell mediated immune response and is similar to the effects induced by exposure to ?-casein. Our results suggest that the expression of rGFP-?(S1)Cas in NZ9000 may facilitate in vivo applications of this system aimed at improving the specificity of immunological responses to specific milk allergen. PMID:22437853

Shigemori, Suguru; Yonekura, Shinichi; Sato, Takashi; Nakanishi, Maya; Otani, Hajime; Shimosato, Takeshi

2012-06-01

247

Truncation of PstS1 antigen of Mycobacterium tuberculosis improves diagnostic efficiency.  

PubMed

PstS1, also named 38-kDa antigen, is one of the earliest known immune-dominant antigens of Mycobacterium tuberculosis and it has been commonly used in serodiagnostic tests. We constructed a truncated version, tnPstS1, by removing 96 and 14 amino acid residues from the N- and C-terminals, respectively of the native PstS1. The native and the truncated 29.5 kDa proteins were expressed in insoluble forms in Escherichia coli to levels of 15% and 25% of the total cell proteins, respectively. Both the variant molecules reacted equally well with the antisera raised in rabbit against the native protein. PstS1 and tnPstS1 were evaluated through ELISA against plasma samples from 160 culture positive tuberculosis patients and 40 healthy controls. With tnPstS1 43% of the patient samples were detected positive for the antibody as compared to only 36% in the case of the native PstS1. Data for the secondary structures of the native and the truncated variants as obtained by circular dichroism agreed with the known 3-D structure of the native protein and the predicted structure of the truncated version, respectively. The results show that the truncated tnPstS1 is more efficient as compared to the native PstS1 for use as a serodiagnostic agent. PMID:23978525

Khurshid, Sana; Khalid, Ruqyya; Afzal, Madeeha; Waheed Akhtar, M

2013-11-01

248

The Paris CM chondrite: Secondary minerals and asteroidal processing  

NASA Astrophysics Data System (ADS)

We report a petrographic and mineralogical survey of Paris, a new CM chondrite considered to be the least-altered CM identified so far (Hewins et al.). Compared to other CMs, Paris exhibits (1) a higher concentration of Fe-Ni metal beads, with nickel contents in the range 4.1-8.1 wt%; (2) the systematic presence of thin lamellae and tiny blebs of pentlandite in pyrrhotite grains; and (3) ubiquitous tochilinite/cronstedtite associations with higher FeO/SiO2 and S/SiO2 ratios. In addition, Paris shows the highest concentration of trapped 36Ar reported so far for a CM chondrite (Hewins et al.). In combination with the findings of previous studies, our data confirm the reliability of (1) the alteration sequence based on the chemical composition of tochilinite/cronstedtite associations to quantify the fluid alteration processes and (2) the use of Cr content variability in type II ferroan chondrule olivine as a proxy of thermal metamorphism. In contrast, the scales based on (1) the Fe3+ content of serpentine in the matrix to estimate the degree of aqueous alteration and (2) the chemical composition of Fe-Ni metal beads for quantifying the intensity of the thermal metamorphism are not supported by the characteristics of Paris. It also appears that the amount of trapped 36Ar is a sensitive indicator of the secondary alteration modifications experienced by chondrites, for both aqueous alteration and thermal metamorphism. Considering Paris, our data suggest that this chondrite should be classified as type 2.7 as it suffered limited but significant fluid alteration and only mild thermal metamorphism. These results point out that two separated scales should be used to quantify the degree of the respective role of aqueous alteration and thermal metamorphism in establishing the characteristics of CM chondrites.

Marrocchi, Yves; Gounelle, Matthieu; Blanchard, Ingrid; Caste, Florent; Kearsley, Anton T.

2014-07-01

249

An autoguider system for the 40 CM Schmidt telescope  

NASA Astrophysics Data System (ADS)

An autoguider system was constructed for the 40 cm Schmidt telescope at the Ouda Station. The sensor of the guider, a type ITT FW 130 image dissector, is attached to the guiding telescope. A microprocessor is introduced for processing the sensor output and for correcting the guiding error of the telescope. This enables the broadening of the objective prism spectra by a simple software. The microprocessor is used also for other auxiliary functions for the telescope control.

Ohtani, H.; Ichikawa, T.; Sasaki, T.; Saito, K.; Tsujimura, T.

1983-03-01

250

Solar Noble Gas Microdistributions in Murchison and CM Rim Formation  

Microsoft Academic Search

Introduction. Identifiable components of certain carbonaceous chondrites have been interpreted as nebula products. MacPherson et al. [1] described some rims around refractory inclusions in Allende (C3V) as accretionary, and Metzler et al. [2] attributed a nebular origin to fine-grained dust mantles (rims) in CM meteorites. In nebula formation scenarios such as that evoked by Metzler et al., we would expect

D. S. Woolum; C. M. Hohenberg; K. Kehm; K. Poelstra; E. Guntalilib

1995-01-01

251

Power distribution for an Am/Cm bushing melter  

SciTech Connect

Decades of nuclear material production at the Savannah River Site (SRS) has resulted in the generation of large quantities of the isotopes Am{sup 243} and Cm{sup 244}. Currently, the Am and Cm isotopes are stored as a nitric acid solution in a tank. The Am and Cm isotopes have great commercial value but must be transferred to ORNL for processing. The nitric acid solution contains other isotopes and is intensely radioactive, which makes storage a problem and precludes shipment in the liquid form. In order to stabilize the material for onsite storage and to permit transport the material from SRS to ORNL, it has been proposed that the Am and Cm be separated from other isotopes in the solution and vitrified. Vitrification will be effected by depositing a liquid feed stream containing the isotopes in solution, together with a stream of glass frit, onto the top of a molten glass pool in a melter. The glass is non-conducting and the melter is a Platinum/Rhodium alloy vessel which is heated by passing an electric current through it. Because most of the power is required to evaporate the liquid feed at the top of the glass pool, power demands differ for the upper and lower parts of the melter. In addition, the melter is batch fed so that the local power requirements vary with time. In order to design a unique split power supply, which ensures adequate local power delivery, an analysis of the melter power distribution was performed with the ABAQUS finite element code. ABAQUS was used to calculate the electric potential and current density distributions in the melter for a variety of current and potential boundary conditions. The results of the calculation were compared with test data and will be used to compute power densities for input to a computational fluid dynamics model for the melter.

Gong, C.; Hardy, B.J.

1996-12-31

252

The Paris CM chondrite: Secondary minerals and asteroidal processing  

NASA Astrophysics Data System (ADS)

We report a petrographic and mineralogical survey of Paris, a new CM chondrite considered to be the least-altered CM identified so far (Hewins et al. ). Compared to other CMs, Paris exhibits (1) a higher concentration of Fe-Ni metal beads, with nickel contents in the range 4.1-8.1 wt%; (2) the systematic presence of thin lamellae and tiny blebs of pentlandite in pyrrhotite grains; and (3) ubiquitous tochilinite/cronstedtite associations with higher FeO/SiO2 and S/SiO2 ratios. In addition, Paris shows the highest concentration of trapped 36Ar reported so far for a CM chondrite (Hewins et al. ). In combination with the findings of previous studies, our data confirm the reliability of (1) the alteration sequence based on the chemical composition of tochilinite/cronstedtite associations to quantify the fluid alteration processes and (2) the use of Cr content variability in type II ferroan chondrule olivine as a proxy of thermal metamorphism. In contrast, the scales based on (1) the Fe3+ content of serpentine in the matrix to estimate the degree of aqueous alteration and (2) the chemical composition of Fe-Ni metal beads for quantifying the intensity of the thermal metamorphism are not supported by the characteristics of Paris. It also appears that the amount of trapped 36Ar is a sensitive indicator of the secondary alteration modifications experienced by chondrites, for both aqueous alteration and thermal metamorphism. Considering Paris, our data suggest that this chondrite should be classified as type 2.7 as it suffered limited but significant fluid alteration and only mild thermal metamorphism. These results point out that two separated scales should be used to quantify the degree of the respective role of aqueous alteration and thermal metamorphism in establishing the characteristics of CM chondrites.

Marrocchi, Yves; Gounelle, Matthieu; Blanchard, Ingrid; Caste, Florent; Kearsley, Anton T.

2014-06-01

253

Membrane Insertion and Bilayer Perturbation by Antimicrobial Peptide CM15  

Microsoft Academic Search

Antimicrobial peptides (AMPs) are an important component of innate immunity and have generated considerable interest as a potential new class of antibiotic. The biological activity of AMPs is strongly influenced by peptide-membrane interactions; however, for many of these peptides the molecular details of how they disrupt and\\/or translocate across target membranes are not known. CM15 is a linear, synthetic hybrid

Sara Pistolesi; Rebecca Pogni; Jimmy B. Feix

2007-01-01

254

Control logic for a 30 cm diameter ion thruster  

NASA Technical Reports Server (NTRS)

The various missions to be performed by the 30-cm diameter mercury bombardment thruster engine are discussed. The operating constraints imposed by the thermal environment, allowable time to reach steady state operation, and the number of start-ups required are examined. The variety of requirements is further analyzed for the impact on the basic control logic for the engine. The control logic is divided into the start-up, run, and shutdown modes of operation. The start-up mode is reported.

Bechtel, R. T.

1975-01-01

255

The Impact of ICD-9-CM Code Rank Order on the Estimated Prevalence of Clostridium difficile Infections  

PubMed Central

Background.?US estimates of the Clostridium difficile infection (CDI) burden have utilized International Classification of Disease, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis codes. Whether ICD-9-CM code rank order affects CDI prevalence estimates is important because the National Hospital Discharge Survey (NHDS) and the Nationwide Inpatient Sample (NIS) have varying limits on the number of ICD-9-CM codes collected. Methods.?ICD-9-CM codes for CDI (008.45), C. difficile toxin assay results, and dates of admission and discharge were collected from electronic hospital databases for adult patients admitted to 4 hospitals in the United States from July 2000 through June 2006. CDI prevalence per 1000 discharges was calculated and compared for NHDS and NIS limits and toxin assay results from the same hospitals. CDI prevalence estimates were compared using the ?2 test, and the test of equality was used to compare slopes. Results.?CDI prevalence measured by NIS criteria was significantly higher than that measured using NHDS criteria (10.7 cases per 1000 discharges versus 9.4 cases per 1000 discharges; P < .001) in the 4 hospitals. CDI prevalence measured by toxin assay results was 9.4 cases per 1000 discharges (P = .57 versus NHDS). However, the CDI prevalence increased more rapidly over time when measured according to the NHDS criteria than when measured according to toxin assay results (?= 1.09 versus 0.84; P = .008). Conclusions.?Compared with the NHDS definition, the NIS definition captured 12% more CDI cases and reported significantly higher CDI rates. Rates calculated using toxin assay results were not different from rates calculated using NHDS criteria, but CDI prevalence appeared to increase more rapidly when measured by NHDS criteria than when measured by toxin assay results.

Butler, Anne M.; Nyazee, Humaa A.; Reske, Kimberly A.; Yokoe, Deborah S.; Mayer, Jeanmarie; Mangino, Julie E.; Khan, Yosef M.; Fraser, Victoria J.

2011-01-01

256

Lobectomy vs. segmentectomy for NSCLC (T<2 cm)  

PubMed Central

The extent of surgical resection for peripheral clinical T1N0M0 non-small cell lung cancer (NSCLC) ?2 cm continues to be a matter of debate. Eighteen years ago, a randomized controlled trial (RCT) established lobectomy as the standard of care for peripheral clinical T1N0M0 NSCLC. However, numerous publications since then have reported similar outcomes for patients treated with segmentectomy or lobectomy for peripheral clinical T1N0M0 NSCLC 2 cm or smaller in size. The majority of these publications are retrospective studies. Two ongoing RCTs aim to resolve this debate, one in Japan and the other in the United States. This manuscript is a comprehensive review of the literature that compares lobectomy to segmentectomy for peripheral clinical T1N0M0 NSCLC 2 cm or smaller in size. Until data from the ongoing RCTs become available, this literature review provides the best evidence to guide the thoracic surgeon in the management of these patients.

Swanson, Scott J.

2014-01-01

257

Distinct Distribution of Purines in CM and CR Carbonaceous Chondrites  

NASA Technical Reports Server (NTRS)

Carbonaceous meteorites contain a diverse suite of organic molecules and delivered pre biotic organic compounds, including purines and pyrimidines, to the early Earth (and other planetary bodies), seeding it with the ingredients likely required for the first genetic material. We have investigated the distribution of nucleobases in six different CM and CR type carbonaceous chondrites, including fivc Antarctic meteorites never before analyzed for nucleobases. We employed a traditional formic acid extraction protocol and a recently developed solid phase extraction method to isolate nucleobases. We analyzed these extracts by high performance liquid chromatography with UV absorbance detection and tandem mass spectrometry (HPLC-UV -MS/MS) targeting the five canonical RNAIDNA bases and hypoxanthine and xanthine. We detected parts-per-billion levels of nucleobases in both CM and CR meteorites. The relative abundances of the purines found in Antarctic CM and CR meteorites were clearly distinct from each other suggesting that these compounds are not terrestrial contaminants. One likely source of these purines is formation by HCN oligomerization (with other small molecules) during aqueous alteration inside the meteorite parent body. The detection of the purines adenine (A), guanine (0), hypoxanthine (HX), and xanthine (X) in carbonaceous meteorites indicates that these compounds should have been available on the early Earth prior to the origin of the first genetic material.

Callahan, Michael P.; Stern, Jennifer C.; Glavin, Daniel P.; Smith, Karen E.; Martin, Mildred G.; Dworkin, Jason P.

2010-01-01

258

Blocking peptides against HBV: PreS1 protein selected from a phage display library  

SciTech Connect

Highlights: {yields} Successfully selected specific PreS1-interacting peptides by using phage displayed library. {yields} Alignment of the positive phage clones revealed a consensus PreS1 binding motif. {yields} A highly enriched peptide named P7 had a strong binding ability for PreS1. {yields} P7 could block PreS1 attachment. -- Abstract: The PreS1 protein is present on the outermost part of the hepatitis B virus (HBV) surface and has been shown to have a pivotal function in viral infectivity and assembly. The development of reagents with high affinity and specificity for PreS1 is of great significance for early diagnosis and treatment of HBV infection. A phage display library of dodecapeptide was screened for interactions with purified PreS1 protein. Alignment of the positive phage clones revealed a putative consensus PreS1 binding motif of HX{sub n}HX{sub m}HP/R. Moreover, a peptide named P7 (KHMHWHPPALNT) was highly enriched and occurred with a surprisingly high frequency of 72%. A thermodynamic study revealed that P7 has a higher binding affinity to PreS1 than the other peptides. Furthermore, P7 was able to abrogate the binding of HBV virions to the PreS1 antibody, suggesting that P7 covers key functional sites on the native PreS1 protein. This newly isolated peptide may, therefore, be a new therapeutic candidate for the treatment of HBV. The consensus motif could be modified to deliver imaging, diagnostic, and therapeutic agents to tissues affected by HBV.

Wang, Wei; Liu, Yang; Zu, Xiangyang; Jin, Rui [State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071 (China)] [State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071 (China); Xiao, Gengfu, E-mail: xiaogf@wh.iov.cn [State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071 (China)] [State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071 (China)

2011-09-09

259

Anomalous splittings of torsional sublevels induced by the aldehyde inversion motion in the S1 state of acetaldehyde.  

PubMed

The G6 group-theoretical high-barrier formalism developed previously for internally rotating and inverting CH3NHD is used to interpret the abnormal torsional splittings in the S1 state of acetaldehyde for levels 14(0-)15(0), 14(0-)15(1), and 14(0-)15(2), where 14(0-) denotes the upper inversion tunneling component of the aldehyde hydrogen and 15 denotes the methyl torsional vibration. This formalism, derived using an extended permutation-inversion group G6m, treats simultaneously methyl torsional tunneling, aldehyde-hydrogen inversion tunneling and overall rotation. Fits to the rotational states of the four pairs of inversion-torsion vibrational levels (14(0+)15(0A,E), 14(0-)15(0A,E)), (14(0+)15(1A,E), 14(0-)15(1A,E)), (14(0+)15(2A,E), 14(0-)15(2A,E)), and (14(0+)15(3A,E), 14(0-)15(3A,E)) are performed, giving root-mean-square deviations of 0.003, 0.004, 0.004, and 0.004 cm(-1), respectively, which are nearly equal to the experimental uncertainty of 0.003 cm(-1). For torsional levels lying near the top of the torsional barrier, this theoretical model, after including higher-order terms, provides satisfactory fits to the experimental data. The partially anomalous K-doublet structure of the S1 state, which deviates from that in a simple torsion-rotation molecule, is fitted using this formalism and is shown to arise from coupling of torsion and rotation motion with the aldehyde-hydrogen inversion. PMID:15268365

Chou, Yung-Ching; Chen, I-Chia; Hougen, Jon T

2004-02-01

260

10 cm x 10 cm Single Gas Electron Multiplier (GEM) X-ray Fluorescence Detector for Dilute Elements  

NASA Astrophysics Data System (ADS)

We have built and tested a 10 cm × 10 cm single Gas Electron Multiplier (GEM) X-ray detector to probe dilute amounts of Fe in a prepared sample. The detector uses Argon/Carbon Dioxide (75/25) gas mixture flowing at a slow rate through a leak proof Plexi-glass enclosure held together by O-rings and screws. The Fluorescence X-ray emitted by the element under test is directed through a Mylar window into the drift region of the detector where abundant gas is flowing. The ionized electrons are separated, drifted into the high electric field of the GEM, and multiplied by impact ionization. The amplified negatively charged electrons are collected and further amplified by a Keithley amplifier to probe the absorption edge of the element under test using X-ray absorption spectroscopy technique. The results show that the GEM detector provided good results with less noise as compared with a Silicon drift detector (SDD).

Shaban, E. H.; Siddons, D. P.; Seifu, D.

2014-03-01

261

Imaging and timing performance of 1 cm x 1 cm position-sensitive solid-state photomultiplier  

NASA Astrophysics Data System (ADS)

We have designed and built a large-area 1cm × 1cm position-sensitive solid-state photomultiplier (PS-SSPM) for use in detector design for medical imaging applications. Our new large-area PS-SSPM concept implements resistive network between the micro-pixels, which are photodiodes operated in Geiger mode, called Geiger Photodiodes (GPDs), to provide continuous position sensitivity. Here we present imaging and timing performance of the large-area PS-SSPM for different temperatures and operating biases to find the optimum operating parameters for the device in imaging applications. A detector module was built by coupling a polished 8 × 8 LYSO array, with 1 × 1 × 20 mm3 elements, to a 1 × 1 cm2 PS-SSPM. Flood images recorded at room temperature show good crystal separation as all 64 elements were separated from each other. Cooling the device at 10 °C showed significant improvement. The device optimum bias voltage was ~ 4.5V over breakdown voltage. The coincidence timing resolution was improved significantly by increasing the operating bias, as well as by lowering the temperature to 0 °C. Results show excellent imaging performance and good timing response with a large-area PS-SSPM device.

Dokhale, P.; Schmall, J.; Stapels, C.; Christian, J.; Cherry, S. R.; Squillante, M. R.; Shah, K.

2013-02-01

262

10(-7) contrast ratio at 4.5lambda/D: New results obtained in laboratory experiments using nano-fabricated coronagraph and multi-Gaussian shaped pupil masks.  

PubMed

We present here new experimental results on high contrast imaging of 10-7 at 4.lambda/D (lambda=0.820 microns) by combining a circular focal plane mask (coronagraph) of 2.5lambda/D diameter and a multi-Gaussian pupil plane mask. Both the masks were fabricated on very high surface quality (lambda/30) BK7 optical substrates using nano-fabrication techniques of photolithography and metal lift-off. This process ensured that the shaped masks have a useable edge roughness better than lambda/4 (rms error better than 0.2 microns), a specification that is necessary to realize the predicted theoretical limits of any mask design. Though a theoretical model predicts a contrast level of 10-12, the background noise of the observed images was speckle dominated which reduced the contrast level to 4x10-7 at 4.5lambda/D. The optical setup was built on the University of Illinois Seeing Improvement System (UnISIS) optics table which is at the Coude focus of the 2.5-m telescope of the Mt. Wilson Observatory. We used a 0.820 micron laser source coupled with a 5 micron single-mode fiber to simulate an artificial star on the optical test bench of UnISIS. PMID:19495130

Chakraborty, Abhijit; Thompson, Laird; Rogosky, Michael

2005-04-01

263

Effect of Niobium doping on structural, thermal, sintering and electrical properties of Bi{sub 4}V{sub 1.8}Cu{sub 0.2}O{sub 10.7}  

SciTech Connect

Doping Bi{sub 4}V{sub 1.8}Cu{sub 0.2}O{sub 10.7} with niobium has led to the formation of the Bi{sub 4}V{sub 1.8}Cu{sub 0.2-x}Nb{sub x}O{sub 10.7+3x/2} solid solution. X-ray diffraction and thermal analysis have shown that only the compound with x=0.05 presents a tetragonal symmetry with a {gamma}{sup '} polymorph while the other compositions are of {beta} polymorph. The influence of sintering temperature on the microstructure of the samples was investigated by the scanning electron microscopy (SEM). The ceramics sintered at temperatures higher than 820{sup o}C present micro-craks. The evolution of the electrical conductivity with temperature and the degree of substitution has been investigated by impedance spectroscopy. Among all compositions studied the sample with x=0.05 presents the highest value of the conductivity.

Alga, M. [Centre d'Excellence de Recherche sur les Materiaux, Universite Cadi Ayyad, Faculte des Sciences Semlalia, Marrakech (Morocco); Ammar, A. [Centre d'Excellence de Recherche sur les Materiaux, Universite Cadi Ayyad, Faculte des Sciences Semlalia, Marrakech (Morocco); Tanouti, B. [Centre d'Excellence de Recherche sur les Materiaux, Universite Cadi Ayyad, Faculte des Sciences Semlalia, Marrakech (Morocco); Outzourhit, A. [Laboratoire de Physique du Solide et des Couches Minces, Departement de physique, Faculte des Sciences Semlalia, Marrakech (Morocco); Mauvy, F. [Institut de Chimie de la Matiere Condensee de Bordeaux, Av. Dr A.Schweitzer, 33608, Pessac (France)]. E-mail: mauvy@icmcb-bordeaux.cnrs.fr; Decourt, R. [Institut de Chimie de la Matiere Condensee de Bordeaux, Av. Dr A.Schweitzer, 33608, Pessac (France)

2005-09-15

264

Calcium alone does not fully activate the thin filament for S1 binding to rigor myofibrils.  

PubMed Central

Skeletal muscle contraction is regulated by calcium via troponin and tropomyosin and appears to involve cooperative activation of cross-bridge binding to actin. We studied the regulation of fluorescent myosin subfragment 1 (fS1) binding to rigor myofibrils over a wide range of fS1 and calcium levels using highly sensitive imaging techniques. At low calcium and low fS1, the fluorescence was restricted to the actin-myosin overlap region. At high calcium and very low fS1, the fluorescence was still predominantly in the overlap region. The ratio of nonoverlap to overlap fluorescence intensity showed that increases in the fS1 level resulted in a shift in maximum fluorescence from the overlap to the nonoverlap region at both low and high calcium; this transition occurred at lower fS1 levels in myofibrils with high calcium. At a fixed fS1 level, increases in calcium also resulted in a shift in maximum fluorescence from the overlap region to the nonoverlap region. These results suggest that calcium alone does not fully activate the thin filament for rigor S1 binding and that, even at high calcium, the thin filament is not activated along its entire length. Images FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 7 FIGURE 9 FIGURE 11

Swartz, D R; Moss, R L; Greaser, M L

1996-01-01

265

Host endothelial S1PR1 regulation of vascular permeability modulates tumor growth.  

PubMed

Understanding vascular growth and maturation in developing tumors has important implications for tumor progression, spread, and ultimately host survival. Modulating the signaling of endothelial G protein-coupled receptors (GPCRs) in blood and lymphatic vessels can enhance or limit tumor progression. Sphingosine 1-phosphate receptor 1 (S1PR1) is a GPCR for circulating lysophospholipid S1P that is highly expressed in blood and lymphatic vessels. Using the S1PR1- enhanced green fluorescent protein (eGFP) mouse model in combination with intravital imaging and pharmacologic modulation of S1PR1 signaling, we show that boundary conditions of high and low S1PR1 signaling retard tumor progression by enhancing or destabilizing neovasculature integrity, respectively. In contrast, midrange S1PR1 signaling, achieved by receptor antagonist titration, promotes abundant growth of small, organized vessels and thereby enhances tumor progression. Furthermore, in vivo S1PR1 antagonism supports lung colonization by circulating tumor cells. Regulation of endothelial S1PR1 dynamically controls vascular integrity and maturation and thus modulates angiogenesis, tumor growth, and hematogenous metastasis. PMID:24740542

Sarkisyan, Gor; Gay, Laurie J; Nguyen, Nhan; Felding, Brunhilde H; Rosen, Hugh

2014-07-01

266

Draft Genome Sequence of Bacillus subtilis Strain S1-4, Which Degrades Feathers Efficiently  

PubMed Central

Bacillus subtilis strain S1-4, with the capacity to efficiently degrade feathers, was isolated from chicken feathers. Sequencing showed that the genome of strain S1-4 differs from that of other B. subtilis strains, with limited insertions and deletions. The genome encodes multiple extracellular proteases and keratinases.

Yong, Bin; Yang, Bin-Qing; Zhao, Chuan-Wu

2013-01-01

267

Sphingosine 1-phosphate induces filopodia formation through S1PR2 activation of ERM proteins.  

PubMed

Previously we demonstrated that the sphingolipids ceramide and S1P (sphingosine 1-phosphate) regulate phosphorylation of the ERM (ezrin/radixin/moesin) family of cytoskeletal proteins [Canals, Jenkins, Roddy, Hernande-Corbacho, Obeid and Hannun (2010) J. Biol. Chem. 285, 32476-3285]. In the present article, we show that exogenously applied or endogenously generated S1P (in a sphingosine kinase-dependent manner) results in significant increases in phosphorylation of ERM proteins as well as filopodia formation. Using phosphomimetic and non-phosphorylatable ezrin mutants, we show that the S1P-induced cytoskeletal protrusions are dependent on ERM phosphorylation. Employing various pharmacological S1PR (S1P receptor) agonists and antagonists, along with siRNA (small interfering RNA) techniques and genetic knockout approaches, we identify the S1PR2 as the specific and necessary receptor to induce phosphorylation of ERM proteins and subsequent filopodia formation. Taken together, the results demonstrate a novel mechanism by which S1P regulates cellular architecture that requires S1PR2 and subsequent phosphorylation of ERM proteins. PMID:23106337

Gandy, K Alexa Orr; Canals, Daniel; Adada, Mohamad; Wada, Masayuki; Roddy, Patrick; Snider, Ashley J; Hannun, Yusuf A; Obeid, Lina M

2013-02-01

268

Enhanced Raman scattering from cesium suboxides on silver particles and the structure of S-1 photocathodes  

NASA Technical Reports Server (NTRS)

An explanation is given for the results of recent enhanced Raman scattering studies of photomultiplier tubes with S-1 photocathode surfaces which indicated the presence of Cs11O3 but not Cs2O. The reason for the discrepancy between the currently accepted model of the S-1 and this recent result is discussed.

Bates, C. W., Jr.

1984-01-01

269

Embolisation of Small (< 3 cm) Brain Arteriovenous Malformations  

PubMed Central

Summary The role of embolisation in the treatment of small (< 3cm) brain arteriovenous malformations (AVMs) has not been elucidated. We reviewed our experience using embolisation in the treatment of small AVMs and correlated a proposed grading system based on the angioarchitecture to the percentage obliteration achieved by embolisation. Eighty-one small AVMs in 80 patients were embolised from 1984 to 1999. The age range was from 3 to 72 years. The AVMs were given a score from 0 to 6 based on the angioarchitecture. The assigned scores were as follows: nidus (fistula = 0, < 1 cm = 1,1-3 cm = 2), type of feeding arteries (cortical = 0, perforator or choroidal = 1), number of feeding arteries (single = 0, multiple -2) and number of draining veins (single = 0\\ multiple - 1). Angiographic results based on percentage obliteration were grouped into three categories: complete, 66-99%, and 0-65%. The goal of embolisation was cure in 27 AVMs, pre-surgical in 23, pre-radiosurgery in 26, and elimination of an aneurysm in five. Embolisation achieved complete obliteration in 22 (27%) of the 81 AVMs. In the AVMs where the goal was cure, 19 (70%) of 27 were completely obliterated. In the AVMs with angioarchitecture scores of 0-2, 12 (86%) of 14 were cured, with scores of 3-4, 8 (34%) of 24 were cured and with scores of 5-6, 2 (4%) of 44 were cured. Embolisation resulted in transient morbidity of 5.0%, permanent morbidity of 2.5%, and mortality of 1.2%. There were no complications in AVMs with scores of 0-2. Embolisation is an effective treatment of small AVMs when the angioarchitecture is favourable (scores 0-2). This includes pure fistulas and AVMs with a single, pial, feeding artery.

Willinsky, R.; Goyal, M.; terBrugge, K.; Montanera, W.; Wallace*, M.G; Tymianski*, M.

2001-01-01

270

Evaluation of ICD-9-CM Codes for Craniofacial Microsomia  

PubMed Central

Background Craniofacial microsomia (CFM) is a congenital condition characterized by microtia and mandibular underdevelopment. Healthcare databases and birth defects surveillance programs could be used to improve knowledge of CFM. However, no specific ICD-9-CM code exists for this condition, which makes standardized data collection challenging. Our aim was to evaluate the validity of existing ICD-9-CM codes to identify individuals with CFM. Methods Study sample eligibility criteria were developed by an expert panel and matched to 11 ICD-9-CM codes. We queried hospital discharge data from two craniofacial centers and identified a total of 12,254 individuals who had ? 1 potentially CFM-related code(s). We reviewed all (n=799) medical records identified at the University of North Carolina (UNC) and 500 randomly selected records at Seattle Children’s Hospital (SCH). Individuals were classified as a CFM case or non-case. Results Thirty-two individuals (6%) at SCH and 93 (12%) at UNC met the CFM eligibility criteria. At both centers, 59% of cases and 95% of non-cases had only one code assigned. At both centers, the most frequent codes were 744.23 (microtia), 754.0 and 756.0 (nonspecific codes), and the code 744.23 had a positive predictive value (PPV) >80% and sensitivity >70%. The code 754.0 had a sensitivity of 3% (PPV<1%) at SCH and 36% (PPV=5%) at UNC, whereas 756.0 had a sensitivity of 38% (PPV=5%) at SCH and 18% (PPV=26%) at UNC. Conclusions These findings suggest the need for a specific CFM code to facilitate CFM surveillance and research.

Luquetti, Daniela V.; Saltzman, Babette S.; Vivaldi, Daniela; Pimenta, Luiz A.; Hing, Anne V.; Cassell, Cynthia H.; Starr, Jacqueline R.; Heike, Carrie L.

2012-01-01

271

2112 new 21-cm line measurements (Theureau+ 1998)  

NASA Astrophysics Data System (ADS)

This catalogue contains 2112 new 21-cm neutral hydrogen line measurements carried out with the meridian transit Nancay radiotelescope. Among these data we give also 213 new radial velocities which complement those listed in three previous papers of this series. Table2.dat is the list of corrected astrophysical HI-parameters (name, coordinates, systemic heliocentric velocity, line-width at two levels, log of maximum circular velocity, HI-flux and signal to noise ratio) The folder fig5 contains the files page01.ps, page02.ps ... corresponding to Figure 5, i.e. the HI-profiles of the galaxies listed in table2.dat. (2 data files).

Theureau, G.; Bottinelli, L.; Coudreau-Durand, N.; Gouguenheim, L.; Hallet, N.; Loulergue, M.; Paturel, G.; Teerikorpi, P.

1998-01-01

272

Recycle Requirements for NASA's 30 cm Xenon Ion Thruster  

NASA Technical Reports Server (NTRS)

Electrical breakdowns have been observed during ion thruster operation. These breakdowns, or arcs, can be caused by several conditions. In flight systems, the power processing unit must be designed to handle these faults autonomously. This has a strong impact on power processor requirements and must be understood fully for the power processing unit being designed for the NASA Solar Electric Propulsion Technology Application Readiness program. In this study, fault conditions were investigated using a NASA 30 cm ion thruster and a power console. Power processing unit output specifications were defined based on the breakdown phenomena identified and characterized.

Pinero, Luis R.; Rawlin, Vincent K.

1994-01-01

273

Performance mapping of a 30 cm engineering model thruster  

NASA Technical Reports Server (NTRS)

A 30 cm thruster representative of the engineering model design has been tested over a wide range of operating parameters to document performance characteristics such as electrical and propellant efficiencies, double ion and beam divergence thrust loss, component equilibrium temperatures, operational stability, etc. Data obtained show that optimum power throttling, in terms of maximum thruster efficiency, is not highly sensitive to parameter selection. Consequently, considerations of stability, discharge chamber erosion, thrust losses, etc. can be made the determining factors for parameter selection in power throttling operations. Options in parameter selection based on these considerations are discussed.

Poeschel, R. L.; Vahrenkamp, R. P.

1975-01-01

274

Radiated and conducted EMI from a 30-cm ion thruster  

NASA Technical Reports Server (NTRS)

In order to properly assess the interaction of a spacecraft with the EMI environment produced by an ion thruster, the EMI environment was characterized. Therefore, radiated and conducted emissions were measured from a 30-cm mercury ion thruster. The ion thruster beam current varied from zero to 2.0 amperes and the emissions were measured from 5 KHz to 200 MHz. Several different types of antennas were used to obtain the measurements. The various measurements that were made included: magnetic field due to neutralizer/beam current loop; radiated electric fields of thruster and plume; and conducted emissions on arc discharge, neutralizer keeper and magnetic baffle lines.

Whittlesey, A. C.; Peer, W.

1981-01-01

275

The 100 cm solar telescope primary mirror study  

NASA Technical Reports Server (NTRS)

The manufacturing impact of primary mirror configuration on the performance of a 100 cm aperture solar telescope was studied. Three primary mirror configurations were considered: solid, standard lightweight, and mushroom. All of these are of low expansion material. Specifically, the study consisted of evaluating the mirrors with regard to: manufacturing metrology, manufacturing risk factors and ultimate quality assessment. As a result of this evaluation, a performance comparison of the configurations was made, and a recommendation of mirror configuration is the final output. These evaluations, comparisons and recommendations are discussed in detail. Other investigations were completed and are documented in the appendices.

1975-01-01

276

A multiple thruster array for 30-cm thrusters  

NASA Technical Reports Server (NTRS)

The 3.0-m diameter chamber of the 7.6-m diameter by 21.4-m long vacuum tank at NASA LeRC was modified to permit testing of an array of up to six 30-cm thrusters with a variety of laboratory and thermal vacuum bread-board power systems. A primary objective of the Multiple Thruster Array (MTA) program is to assess the impact of multiple thruster operation on individual thruster and power processor requirements. The areas of thruster startup, steady-state operation, throttling, high voltage recycle, thrust vectoring, and shutdown are of special concern. The results of initial tests are reported.

Rawlin, V. K.; Mantenieks, M. A.

1975-01-01

277

Status of 30 cm mercury ion thruster development  

NASA Technical Reports Server (NTRS)

Two engineering model 30-cm ion thrusters were assembled, calibrated, and qualification tested. This paper discusses the thruster design, performance, and power system. Test results include documentation of thrust losses due to doubly charged mercury ions and beam divergence by both direct thrust measurements and beam probes. Diagnostic vibration tests have led to improved designs of the thruster backplate structure, feed system, and harness. Thruster durability is being demonstrated over a thrust range of 97 to 113 mN at a specific impulse of about 2900 seconds. As of August 15, 1974, the thruster has successfully operated for over 4000 hours.

Sovey, J. S.; King, H. J.

1974-01-01

278

Thermoacoustic imaging of fresh prostates up to 6-cm diameter  

NASA Astrophysics Data System (ADS)

Thermoacoustic (TA) imaging provides a novel contrast mechanism that may enable visualization of cancerous lesions which are not robustly detected by current imaging modalities. Prostate cancer (PCa) is the most notorious example. Imaging entire prostate glands requires 6 cm depth penetration. We therefore excite TA signal using submicrosecond VHF pulses (100 MHz). We will present reconstructions of fresh prostates imaged in a well-controlled benchtop TA imaging system. Chilled glycine solution is used as acoustic couplant. The urethra is routinely visualized as signal dropout; surgical staples formed from 100-micron wide wire bent to 3 mm length generate strong positive signal.

Patch, S. K.; Hanson, E.; Thomas, M.; Kelly, H.; Jacobsohn, K.; See, W. A.

2013-03-01

279

Pan-STARRS 1 Observations of the Unusual Active Centaur P/2011 S1(Gibbs)  

NASA Astrophysics Data System (ADS)

P/2011 S1 (Gibbs) is an outer solar system comet or active Centaur with a similar orbit to that of the famous 29P/Schwassmann-Wachmann 1. P/2011 S1 (Gibbs) has been observed by the Pan-STARRS 1 (PS1) sky survey from 2010 to 2012. The resulting data allow us to perform multi-color studies of the nucleus and coma of the comet. Analysis of PS1 images reveals that P/2011 S1 (Gibbs) has a small nucleus <4 km radius, with colors g P1 – r P1 = 0.5 ± 0.02, r P1 – i P1 = 0.12 ± 0.02, and i P1 – z P1 = 0.46 ± 0.03. The comet remained active from 2010 to 2012, with a model-dependent mass-loss rate of ~100 kg s1. The mass-loss rate per unit surface area of P/2011 S1 (Gibbs) is as high as that of 29P/Schwassmann-Wachmann 1, making it one of the most active Centaurs. The mass-loss rate also varies with time from ~40 kg s1 to 150 kg s1. Due to its rather circular orbit, we propose that P/2011 S1 (Gibbs) has 29P/Schwassmann-Wachmann 1-like outbursts that control the outgassing rate. The results indicate that it may have a similar surface composition to that of 29P/Schwassmann-Wachmann 1. Our numerical simulations show that the future orbital evolution of P/2011 S1 (Gibbs) is more similar to that of the main population of Centaurs than to that of 29P/Schwassmann-Wachmann 1. The results also demonstrate that P/2011 S1 (Gibbs) is dynamically unstable and can only remain near its current orbit for roughly a thousand years.

Lin, H. W.; Chen, Y. T.; Lacerda, P.; Ip, W. H.; Holman, M.; Protopapas, P.; Chen, W. P.; Burgett, W. S.; Chambers, K. C.; Flewelling, H.; Huber, M. E.; Jedicke, R.; Kaiser, N.; Magnier, E. A.; Metcalfe, N.; Price, P. A.

2014-05-01

280

Ribosomal protein S1 unwinds double-stranded RNA in multiple steps  

PubMed Central

The sequence and secondary structure of the 5?-end of mRNAs regulate translation by controlling ribosome initiation on the mRNA. Ribosomal protein S1 is crucial for ribosome initiation on many natural mRNAs, particularly for those with structured 5?-ends, or with no or weak Shine-Dalgarno sequences. Besides a critical role in translation, S1 has been implicated in several other cellular processes, such as transcription recycling, and the rescuing of stalled ribosomes by tmRNA. The mechanisms of S1 functions are still elusive but have been widely considered to be linked to the affinity of S1 for single-stranded RNA and its corresponding destabilization of mRNA secondary structures. Here, using optical tweezers techniques, we demonstrate that S1 promotes RNA unwinding by binding to the single-stranded RNA formed transiently during the thermal breathing of the RNA base pairs and that S1 dissociation results in RNA rezipping. We measured the dependence of the RNA unwinding and rezipping rates on S1 concentration, and the force applied to the ends of the RNA. We found that each S1 binds 10 nucleotides of RNA in a multistep fashion implying that S1 can facilitate ribosome initiation on structured mRNA by first binding to the single strand next to an RNA duplex structure (“stand-by site”) before subsequent binding leads to RNA unwinding. Unwinding by multiple small substeps is much less rate limited by thermal breathing than unwinding in a single step. Thus, a multistep scheme greatly expedites S1 unwinding of an RNA structure compared to a single-step mode.

Qu, Xiaohui; Lancaster, Laura; Noller, Harry F.; Bustamante, Carlos; Tinoco, Ignacio

2012-01-01

281

Ribosomal protein S1 unwinds double-stranded RNA in multiple steps.  

PubMed

The sequence and secondary structure of the 5'-end of mRNAs regulate translation by controlling ribosome initiation on the mRNA. Ribosomal protein S1 is crucial for ribosome initiation on many natural mRNAs, particularly for those with structured 5'-ends, or with no or weak Shine-Dalgarno sequences. Besides a critical role in translation, S1 has been implicated in several other cellular processes, such as transcription recycling, and the rescuing of stalled ribosomes by tmRNA. The mechanisms of S1 functions are still elusive but have been widely considered to be linked to the affinity of S1 for single-stranded RNA and its corresponding destabilization of mRNA secondary structures. Here, using optical tweezers techniques, we demonstrate that S1 promotes RNA unwinding by binding to the single-stranded RNA formed transiently during the thermal breathing of the RNA base pairs and that S1 dissociation results in RNA rezipping. We measured the dependence of the RNA unwinding and rezipping rates on S1 concentration, and the force applied to the ends of the RNA. We found that each S1 binds 10 nucleotides of RNA in a multistep fashion implying that S1 can facilitate ribosome initiation on structured mRNA by first binding to the single strand next to an RNA duplex structure ("stand-by site") before subsequent binding leads to RNA unwinding. Unwinding by multiple small substeps is much less rate limited by thermal breathing than unwinding in a single step. Thus, a multistep scheme greatly expedites S1 unwinding of an RNA structure compared to a single-step mode. PMID:22908248

Qu, Xiaohui; Lancaster, Laura; Noller, Harry F; Bustamante, Carlos; Tinoco, Ignacio

2012-09-01

282

Volatiles on solar system objects: Carbon dioxide on Iapetus and aqueous alteration in CM chondrites  

NASA Astrophysics Data System (ADS)

Volatiles are critical in understanding the history of the solar system. We conducted two case studies intended to further this understanding. First, we analyzed the presence of CO2 on Iapetus. Second, we evaluated aqueous alteration in CM chondrites. We studied the distribution, stability and production of CO2 on Saturn's moon Iapetus. We determined that CO2 is concentrated exclusively on Iapetus' dark material with an effective thickness of 31 nm. The total CO2 on Iapetus' surface is 2.3x108 kg. However, CO2 should not be present because it has a limited residence time on the surface of Iapetus. Our thermal calculations and modeling show that CO2 in the form of frost will not remain on Iapetus' surface beyond a few hundred years. Thus, it must be complexed with dark material. However, photodissociation will destroy the observed inventory in ˜1/2 an Earth year. The lack of thermal and radiolytic stability requires an active source. We conducted experiments showing UV radiation generates CO2 under Iapetus-like conditions. We created a simulated regolith by mixing crushed water ice with isotopically labeled carbon. We then irradiated it with UV light at low temperature and pressure, producing 1.1x1015 parts m-2 s-1. Extrapolating to Iapetus, photolysis could generate 8.4x107 kg y-1, which makes photolytic production a good candidate for the source of the CO2 detected on Iapetus. We also studied the aqueous alteration of metal-bearing assemblages in CM chondrites. We examined Murchison, Cold Bokkeveld, Nogoya, and Murray using microscopy, electron microprobe analysis and scanning electron microscopy. Alteration on CM meteorites occurred within at least three microchemical environments: S-rich water, Si-rich water and water without substantial reactive components. Kamacite alters into tochilinite, cronstedtite, or magnetite. Sulfur associated alteration can form accessory minerals: P-rich sulfides, eskolaite and schreibersite. Additionally, we determined that there were two alteration events for some CM chondrites. The first formed a hydrated matrix prior to accretion, indicated by unaltered kamacite surrounded by a hydrated matrix. The second occurred after parent body formation. This event is indicated by large regions with consistent alteration features, surrounded by other regions of less altered material.

Palmer, Eric Edward

2009-12-01

283

Stratospheric measurements of continuous absorption near 2400 per cm  

NASA Astrophysics Data System (ADS)

Measurements of continuous absorption near 2400 per cm by N2 and CO2 over long path lengths in the lower stratosphere are presented. The continua were measured in a stratospheric solar spectrum obtained during sunset with a balloon-borne Michelson interferometer in the 2380-2500 per cm region, and transmittances were calculated by ratioing the amplitudes to those of a high-sun spectrum in order to eliminate the wavelength dependence of the measured flux. Comparison of the measured transmittances with those calculated for a multilayered atmospheric model using laboratory absorption measurements results in a fair agreement, and reveals the primary component of the absorption throughout most of the range to be N2, with the CO2 contribution equal to that of N2 only at the CO2 band head. In this region, the shape of the continuum is very sensitive to the sub-Lorentzian line shape assumed in the calculations, and so, if the shape of the N2 continuum at low temperatures can be determined through laboratory measurements, may be used to infer air-broadened far-wing CO2 line shape.

Rinsland, C. P.; Smith, M. A. H.; Russell, J. M., III; Park, J. H.; Farmer, C. B.

1981-12-01

284

Altimeter error sources at the 10-cm performance level  

NASA Technical Reports Server (NTRS)

Error sources affecting the calibration and operational use of a 10 cm altimeter are examined to determine the magnitudes of current errors and the investigations necessary to reduce them to acceptable bounds. Errors considered include those affecting operational data pre-processing, and those affecting altitude bias determination, with error budgets developed for both. The most significant error sources affecting pre-processing are bias calibration, propagation corrections for the ionosphere, and measurement noise. No ionospheric models are currently validated at the required 10-25% accuracy level. The optimum smoothing to reduce the effects of measurement noise is investigated and found to be on the order of one second, based on the TASC model of geoid undulations. The 10 cm calibrations are found to be feasible only through the use of altimeter passes that are very high elevation for a tracking station which tracks very close to the time of altimeter track, such as a high elevation pass across the island of Bermuda. By far the largest error source, based on the current state-of-the-art, is the location of the island tracking station relative to mean sea level in the surrounding ocean areas.

Martin, C. F.

1977-01-01

285

Electric prototype power processor for a 30cm ion thruster  

NASA Technical Reports Server (NTRS)

An electrical prototype power processor unit was designed, fabricated and tested with a 30 cm mercury ion engine for primary space propulsion. The power processor unit used the thyristor series resonant inverter as the basic power stage for the high power beam and discharge supplies. A transistorized series resonant inverter processed the remaining power for the low power outputs. The power processor included a digital interface unit to process all input commands and internal telemetry signals so that electric propulsion systems could be operated with a central computer system. The electrical prototype unit included design improvement in the power components such as thyristors, transistors, filters and resonant capacitors, and power transformers and inductors in order to reduce component weight, to minimize losses, and to control the component temperature rise. A design analysis for the electrical prototype is also presented on the component weight, losses, part count and reliability estimate. The electrical prototype was tested in a thermal vacuum environment. Integration tests were performed with a 30 cm ion engine and demonstrated operational compatibility. Electromagnetic interference data was also recorded on the design to provide information for spacecraft integration.

Biess, J. J.; Inouye, L. Y.; Schoenfeld, A. D.

1977-01-01

286

Characterization of an 8-cm Diameter Ion Source System  

NASA Technical Reports Server (NTRS)

Results of tests characterizing an 8-cm diameter ion source are presented. The tests were conducted in three separate vacuum test facilities at the University of Alabama-Huntsville, Colorado State University, and L3 Communications' ETI division. Standard ion optics tests describing electron backstreaming and total-voltage-limited impingement current behavior as a function of beam current were used as guidelines for selecting operating conditions where more detailed ion beam measurements were performed. The ion beam was profiled using an in-vacuum actuating probe system to determine the total ion current density and the ion charge state distribution variation across the face of the ion source. Both current density and ExB probes were utilized. The ion current density data were used to obtain integrated beam current, beam flatness parameters, and general beam profile shapes. The ExB probe data were used to determine the ratio of doubly to singly charged ion current. The ion beam profile tests were performed at over six different operating points that spanned the expected operating range of the DAWN thrusters being developed at L3. The characterization tests described herein reveal that the 8-cm ion source is suitable for use in (a) validating plasma diagnostic equipment, (b) xenon ion sputtering and etching studies of spacecraft materials, (c) plasma physics research, and (d) the study of ion thruster optics at varying conditions.

Li, Zhongmin; Hawk, C. W.; Hawk, Clark W.; Buttweiler, Mark S.; Williams, John D.; Buchholtz, Brett

2005-01-01

287

Discovery and First Observations of the 21-cm Hydrogen Line  

NASA Astrophysics Data System (ADS)

Unlike most of the great discoveries in the first decade of radio astronomy after World War II, the 21 cm hydrogen line was first predicted theoretically and then purposely sought. The story is familiar of graduate student Henk van de Hulst's prediction in occupied Holland in 1944 and the nearly simultaneous detection of the line by teams at Harvard, Leiden, and Sydney in 1951. But in this paper I will describe various aspects that are little known: (1) In van de Hulst's original paper he not only worked out possible intensities for the 21 cm line, but also for radio hydrogen recombination lines (not detected until the early 1960s), (2) in that same paper he also used Jansky's and Reber's observations of a radio background to make cosmological conclusions, (3) there was no "race" between the Dutch, Americans, and Australians to detect the line, (4) a fire that destroyed the Dutch team's equipment in March 1950 ironically did not hinder their progress, but actually speeded it up (because it led to a change of their chief engineer, bringing in the talented Lex Muller). The scientific and technical styles of the three groups will also be discussed as results of the vastly differing environments in which they operated.

Sullivan, W. T.

2005-08-01

288

Power processor for a 20CM ion thruster  

NASA Technical Reports Server (NTRS)

A power processor breadboard for the JPL 20CM Ion Engine was designed, fabricated, and tested to determine compliance with the electrical specification. The power processor breadboard used the silicon-controlled rectifier (SCR) series resonant inverter as the basic power stage to process all the power to the ion engine. The breadboard power processor was integrated with the JPL 20CM ion engine and complete testing was performed. The integration tests were performed without any silicon-controlled rectifier failure. This demonstrated the ruggedness of the series resonant inverter in protecting the switching elements during arcing in the ion engine. A method of fault clearing the ion engine and returning back to normal operation without elaborate sequencing and timing control logic was evolved. In this method, the main vaporizer was turned off and the discharge current limit was reduced when an overload existed on the screen/accelerator supply. After the high voltage returned to normal, both the main vaporizer and the discharge were returned to normal.

Biess, J. J.; Schoenfeld, A. D.; Cohen, E.

1973-01-01

289

Tank testing of a 2500-cm2 solar panel  

NASA Technical Reports Server (NTRS)

A 50 cm by 50 cm solar array panel test patch was investigated for spacecraft charging and arcing effects. Bombardment with monochromatic electron was carried out. Some objectives of the test were: (1) to estimate at what voltage of electron bombardment arcing would be probable; (2) to find whether the arc's energy would be tolerable or damagingly large; (3) to try and separate thermal and photoeffects; and, (4) to see whether materials used were such as to minimize arcing. Some conclusions were: In sunlight the tracking data relay satellite's solar panel which has ceria glass on the front and conductive paint on the backside is probably a good design for reducing charge-up. In a geomagnetic substorm simulated in testing there will be arcing at the interconnects during eclipse and transitions into and out of eclipse in testing especially in view of the very cold temperatures that will be reached by this lightweight array. Ceria-doped glass is preferred to fused silica glass for reducing charge build up. The Kapton bare patch should still be conductively painted. The differential voltages on the panel determine when arcing first begins, and the electron beam voltages vary depending upon whether the metallic structure is directly grounded or semifloating.

Bever, R. S.; Staskus, J.

1981-01-01

290

Presolar grains in the CM2 chondrite Sutter's Mill  

NASA Astrophysics Data System (ADS)

The Sutter's Mill (SM) carbonaceous chondrite is a regolith breccia, composed predominantly of CM2 clasts with varying degrees of aqueous alteration and thermal metamorphism. An investigation of presolar grains in four Sutter's Mill sections, SM43, SM51, SM2-4, and SM18, was carried out using NanoSIMS ion mapping technique. A total of 37 C-anomalous grains and one O-anomalous grain have been identified, indicating an abundance of 63 ppm for presolar C-anomalous grains and 2 ppm for presolar oxides. Thirty-one silicon carbide (SiC), five carbonaceous grains, and one Al-oxide (Al2O3) were confirmed based on their elemental compositions determined by C-N-Si and O-Si-Mg-Al isotopic measurements. The overall abundance of SiC grains in Sutter's Mill (55 ppm) is consistent with those in other CM chondrites. The absence of presolar silicates in Sutter's Mill suggests that they were destroyed by aqueous alteration on the parent asteroid. Furthermore, SM2-4 shows heterogeneous distributions of presolar SiC grains (12-54 ppm) in different matrix areas, indicating that the fine-grained matrix clasts come from different sources, with various thermal histories, in the solar nebula.

Zhao, Xuchao; Lin, Yangting; Yin, Qing-Zhu; Zhang, Jianchao; Hao, Jialong; Zolensky, Michael; Jenniskens, Peter

2014-06-01

291

Statistical Properties of Interstellar Neutral Hydrogen from 21-CM Absorption Surveys  

NASA Astrophysics Data System (ADS)

The samples of 21-cm absorption spectra from (Crovisier et al., 1978) and from Arecibo (Dickey et al., 1978; Crovisier et al., 1980) are analysed in order to derive the spatial distribution and statistical properties of HI interstellar clouds. Biases caused by velocity blending and spurious features in the Nançay sample are estimated. The distribution of the velocity dispersion inside the clouds peaks around 1 km s-1, but its first moment is ˜1.7 km s-1. The "apparent spin temperature" of the clouds, as deduced from the comparison of 21-cm emission and absorption, is negatively correlated with optical depth, as already known from former studies; several proposed explanations include observational biases and cloud physics. The comparison of the spin temperatures and the velocity dispersions inside the clouds suggests that turbulent and bulk motions inside the clouds are mildly super- sonic, and may contribute to the heating. The mean number of clouds on a line of sight, with optical depth greater than a given limit, is derived: there is for instance an average of 0.25 cloud with ? > 0.12 on a line of sight reduced to |b| = 90°, which corresponds to one such cloud every 700 pc. Spectra at different latitudes were compared assuming a cosecant |b| law, but large-scale local inhomogeneities (especially a deficiency of cold H I at high latitudes) limit the validity of this plane-parallel model. The Arecibo sample contains a relative excess of weak clouds with respect to the sample, which could be due to a more complete Gaussian decomposition of the Arecibo profiles. The distribution of the cloud column densities is found to be proportional to N-1.3HI, and consistent with a mass spectrum proportional to M-1.8. An analysis of the integrated optical depth of the spectra is made, and compared with the analyses of the stellar color excesses. The parameters of the HI interstellar clouds have wide-spread distributions which prevent any description of these objects in terms of a "standard cloud" endowed with average properties.

Crovisier, J.

1981-01-01

292

Enhanced Effect of DNA Immunization plus In Vivo Electroporation with a Combination of Hepatitis B Virus Core-PreS1 and S-PreS1 Plasmids ?  

PubMed Central

To develop a novel, effective HBV therapeutic vaccine, we constructed two HBV DNA immunogens that contained PreS1, HBSS1, and HBCS1. Several delivery methods, such as intramuscular (i.m.) injection, intramuscular injection plus electroporation (i.m.-EP), and intradermal injection plus electroporation (i.d.-EP) were used in a murine model to analyze and compare the immune responses that were induced by the DNA immunogens. We found that i.d.-EP accelerated specific antibody seroconversion and produced high antibody (anti-PreS1, anti-S, and anti-C antibody) titers after HBSS1 and HBCS1 immunization. Combining the HBSS1 and HBCS1 DNA immunogens with i.d.-EP produced the strongest multiantigen (PreS1, S, and C)-specific cellular immune response and the highest specific PreS1 antibody levels. The results indicated that DNA immunization using HBSS1 and HBCS1 might be an ideal candidate, with its ability to elicit robust B and T cell immune responses against multiantigen when combined with optimized delivery technology. The present study provides a basis for the design and rational application of a novel HBV DNA vaccine.

Chen, Hong; Wen, Bo; Deng, Yao; Wang, Wen; Yin, Xiao; Guan, Jie; Ruan, Li; Tan, Wenjie

2011-01-01

293

Rotationally resolved S1-S0 electronic spectra of 2,6-diaminopyridine: a four-fold barrier problem.  

PubMed

A comparison of the electronic properties of the nitrogen-containing rings aniline, 2-aminopyridine, and 2,6-diaminopyridine (26DAP) shows that the potential energy surface of the molecule is significantly affected as more nitrogen atoms are added to the system. High resolution, rotationally resolved spectra of four vibrational bands in the S(1)-S(0) electronic transition of 26DAP were obtained in order to explain these changes. The zig-zagging inertial defects point to a double minimum excited state potential energy surface along the coupled amino group inversion vibrational mode, which becomes a four-fold well (and barrier) problem when the existence of two nearly degenerate isomers is taken into account. Assuming that the molecules are in the lower energy, opposite-side configuration, ab initio calculations were performed using the MP2/6-31G** level of theory to create a potential energy surface modeling the simultaneous antisymmetric NH(2)-inversion mode. The calculated potential energy surface shows a ground electronic state barrier to simultaneous NH(2) inversion of ~220 cm(-1), and a fit to experimental vibrational energy level spacings and relative intensities produces an excited electronic state barrier of ~400 cm(-1). The ground state barrier is less than that in aniline, but the excited state barrier is larger. PMID:20964390

Clements, Casey L; Young, Justin W; Pratt, David W

2010-11-18

294

Global 21 cm signal experiments: A designer's guide  

NASA Astrophysics Data System (ADS)

The global (i.e., spatially averaged) spectrum of the redshifted 21 cm line has generated much experimental interest lately, thanks to its potential to be a direct probe of the epoch of reionization and the dark ages, during which the first luminous objects formed. Since the cosmological signal in question has a purely spectral signature, most experiments that have been built, designed, or proposed have essentially no angular sensitivity. This can be problematic because with only spectral information, the expected global 21 cm signal can be difficult to distinguish from foreground contaminants such as galactic synchrotron radiation, since both are spectrally smooth and the latter is many orders of magnitude brighter. In this paper, we establish a systematic mathematical framework for global signal data analysis. The framework removes foregrounds in an optimal manner, complementing spectra with angular information. We use our formalism to explore various experimental design trade-offs, and find that (1) with spectral-only methods, it is mathematically impossible to mitigate errors that arise from uncertainties in one’s foreground model; (2) foreground contamination can be significantly reduced for experiments with fine angular resolution; (3) most of the statistical significance in a positive detection during the dark ages comes from a characteristic high-redshift trough in the 21 cm brightness temperature; (4) measurement errors decrease more rapidly with integration time for instruments with fine angular resolution; and (5) better foreground models can help reduce errors, but once a modeling accuracy of a few percent is reached, significant improvements in accuracy will be required to further improve the measurements. We show that if observations and data analysis algorithms are optimized based on these findings, an instrument with a 5° wide beam can achieve highly significant detections (greater than 5?) of even extended (high ?z) reionization scenarios after integrating for 500 h. This is in strong contrast to instruments without angular resolution, which cannot detect gradual reionization. Ionization histories that are more abrupt can be detected with our fiducial instrument at the level of tens to hundreds of ?. The expected errors are similarly low during the dark ages, and can yield a 25? detection of the expected cosmological signal after only 100 h of integration.

Liu, Adrian; Pritchard, Jonathan R.; Tegmark, Max; Loeb, Abraham

2013-02-01

295

Cost analysis of S1 and XELOX as adjuvant therapy for gastric cancer.  

PubMed

Both S1 and XELOX (capecitabine+oxaliplatin) have been recommended as an adjuvant treatment for gastric cancer according to the guidelines of the National Comprehensive Cancer Network (NCCN). This study compared the two regimens in terms of monetary costs, assuming equal efficacy of both regimens. Chemotherapy cost data of 188 patients were collected from the medical records, 91 for the S1 group and 97 for XELOX. Costs were classified as direct costs (chemotherapy, hospitalization, venous access, and tests), adverse event-related treatments costs, and societal (travel and time) costs. The total direct costs of S1 and XELOX per cycle per patient were $1938±236 and $2317±315, respectively. S1 cost $27 and $9 less than XELOX on total adverse event-related costs and societal costs, respectively. The total costs of S1 and XELOX were $1994±322 versus $2410±391 per cycle per patient, respectively. The total cost of S1 was 17.3% less than that of XELOX for the average patient. All the differences were statistically significant. S1, compared with XELOX, could be a more affordable option as an adjuvant treatment for gastric cancer when all healthcare resources are taken into account in China. PMID:23629479

He, Jianping; Wen, Feng; Yin, Xude; Zhang, Pengfei; Du, Zedong; He, Xiaofeng; Zhou, Yi; Tang, Ruilei; Li, Meng; Li, Qiu

2013-08-01

296

[Phase I study of sequential S-1 and cyclophosphamide therapy in patients with metastatic breast cancer].  

PubMed

S-1 is a novel oral anticancer agent consisting of tegafur, a prodrug of 5-fluorouracil, and 2 modulators. A phase I study of sequential S-1 and cyclophosphamide(CPA)therapy was conducted to determine the dose-limiting toxicities(DLTs)and recommended doses(RDs)in patients with metastatic or recurrent breast cancer(MBC). Patients with MBC received sequential S-1 and CPA. Chemotherapy consisted of administration of S-1 twice daily on days 1-14 at escalating doses of 40, 50, 65, and 80mg/m2/day and CPA at 100 mg/body/day on days 15-28. The schedule was repeated twice at a 4-week interval. The purposes of this study were to determine the RDs, safety, and efficacy of the regimen. A total of 12 patients were registered. No patients experienced DLTs, and the RDs of S-1 and CPA were 80mg/m2/day and 100 mg/body/day, respectively. The response rate was 50. 0%. In conclusion, sequential therapy with S-1 and CPA could be safely and effectively used for the treatment of MBC, and the RDs for this regimen were determined to be 80mg/m2/day for S-1 and 100 mg/m2/day for CPA. PMID:24047774

Horiguchi, Jun; Takata, Daisuke; Rokutanda, Nana; Nagaoka, Rin; Tokiniwa, Hideaki; Odawara, Hiroki; Kikuchi, Mami; Sato, Ayako; Takeyoshi, Izumi

2013-09-01

297

Cosmic (Super)String Constraints from 21 cm Radiation  

SciTech Connect

We calculate the contribution of cosmic strings arising from a phase transition in the early Universe, or cosmic superstrings arising from brane inflation, to the cosmic 21 cm power spectrum at redshifts z{>=}30. Future experiments can exploit this effect to constrain the cosmic string tension G{mu} and probe virtually the entire brane inflation model space allowed by current observations. Although current experiments with a collecting area of {approx}1 km{sup 2} will not provide any useful constraints, future experiments with a collecting area of 10{sup 4}-10{sup 6} km{sup 2} covering the cleanest 10% of the sky can, in principle, constrain cosmic strings with tension G{mu} > or approx. 10{sup -10}-10{sup -12} (superstring/phase transition mass scale >10{sup 13} GeV)

Khatri, Rishi; Wandelt, Benjamin D. [Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 W. Green Street, Urbana, Illinois 61801 (United States); Departments of Physics and Astronomy, University of Illinois at Urbana-Champaign, 1002 W. Green Street, Urbana, Illinois 61801 (United States)

2008-03-07

298

Cosmic (Super)String Constraints from 21 cm Radiation.  

PubMed

We calculate the contribution of cosmic strings arising from a phase transition in the early Universe, or cosmic superstrings arising from brane inflation, to the cosmic 21 cm power spectrum at redshifts z > or =30. Future experiments can exploit this effect to constrain the cosmic string tension G mu and probe virtually the entire brane inflation model space allowed by current observations. Although current experiments with a collecting area of approximately 1 km2 will not provide any useful constraints, future experiments with a collecting area of 10(4)-10(6) km2 covering the cleanest 10% of the sky can, in principle, constrain cosmic strings with tension G mu > or = 10(-10)-10(-12) (superstring/phase transition mass scale >10(13) GeV). PMID:18352691

Khatri, Rishi; Wandelt, Benjamin D

2008-03-01

299

Studies of internal sputtering in a 30-cm ion thruster  

NASA Technical Reports Server (NTRS)

Initial studies have been made of the sputtering and deposition phenomena in a 30-cm thruster. Sputtering rates, of the cathode baffle, one of the main sources of sputtered material in a thruster, have been measured by weight loss as a function of several thruster parameters. Sputtering rates were found to increase with both cathode flow rate and beam current when constant discharge voltage of 37 volts and power loses of 185 ev/ion were maintained. Sputtering rates were reduced 24% as discharge voltage was decreased from 37 to 33 volts while keeping discharge power constant. Qualitative agreement was found between sputtering rates obtained by the weight loss and those implied by spectroscopically observed line intensities of the excited iron sputtered atoms. After the completion of the sputtering tests, deposition and sputtering sites inside the thruster were identified.

Mantenieks, M. A.; Rawlin, V. K.

1975-01-01

300

Power processor for a 30cm ion thruster  

NASA Technical Reports Server (NTRS)

A thermal vacuum power processor for the NASA Lewis 30cm Mercury Ion Engine was designed, fabricated and tested to determine compliance with electrical specifications. The power processor breadboard used the silicon controlled rectifier (SCR) series resonant inverter as the basic power stage to process all the power to an ion engine. The power processor includes a digital interface unit to process all input commands and internal telemetry signals so that operation is compatible with a central computer system. The breadboard was tested in a thermal vacuum environment. Integration tests were performed with the ion engine and demonstrate operational compatibility and reliable operation without any component failures. Electromagnetic interference data were also recorded on the design to provide information on the interaction with total spacecraft.

Biess, J. J.; Inouye, L. Y.

1974-01-01

301

Studies of internal sputtering in a 30-cm ion thruster  

NASA Technical Reports Server (NTRS)

Initial studies have been made of the sputtering and deposition phenomena in a 30-cm thruster. Sputtering rates, of the cathode baffle, one of the main sources of sputtered material in a thruster, have beem measured by weight loss as a function of several thruster parameters. Sputtering rates were found to increase with both cathode flow rate and beam current when constant discharge voltage of 37 volts and power losses of 185 ev/ion were maintained. Sputtering rates were reduced 24% as discharge voltage was decreased from 37 to 33 volts while keeping discharge power constant. Qualitative agreement was found between sputtering rates obtained by the weight loss and those implied by spectroscopically observed line intensities of the excited iron sputtered atoms. After the completion of the sputtering tests, deposition and sputtering sites inside the thruster were identified.

Mantenieks, M. A.; Rawlin, V. K.

1975-01-01

302

Control logic for a 30 cm diameter ion thruster  

NASA Technical Reports Server (NTRS)

Tests with a 30 cm thruster having EMT critical components have defined start-up criteria. Of the three phases comprising the start-up mode, the preheat phase is intended to heat critical feed system components to desired temperatures. Of the seven supplies available during the preheat phase, only three were found to be useful for purposes of preheating the thruster. These were the cathode and neutralizer tip heater supplies and the isolator heater supply. If the needed temperatures are attained during preheat, the ignition phase requires only several seconds. The heat phase serves to establish the proper propellant flow rates prior to the transition to the run mode. Using these techniques, a thruster with initial temperatures in the range of -15 to +25 C can be reliably started and provide a 1.0 amp beam within 45 min. High voltage recycle time profiles indicate limitations on several time functions.

Bechtel, R. T.

1975-01-01

303

Hollow cathode restartable 15 cm diameter ion thruster  

NASA Technical Reports Server (NTRS)

The effects of substituting high perveance dished grids for low perveance flat ones on performance variables and plasma properties within a 15 cm modified SERT II thruster are discussed. Results suggest good performance may be achieved as an ion thruster is throttled if the screen grid transparency is decreased with propellant flow rate. Thruster startup tests, which employ a pulsed high voltage tickler electrode between the keeper and the cathode to initiate the discharge, are described. High startup reliability at cathode tip temperatures of about 500 C without excessive component wear over 2000 startup cycles is demonstrated. Testing of a single cusp magnetic field concept of discharge plasma containment is discussed. A theory which explains the observed behavior of the device is presented and proposed thruster modifications and future testing plans are discussed.

Wilbur, P. J.

1973-01-01

304

Astronaut Risk Levels During Crew Module (CM) Land Landing  

NASA Technical Reports Server (NTRS)

The NASA Engineering Safety Center (NESC) is investigating the merits of water and land landings for the crew exploration vehicle (CEV). The merits of these two options are being studied in terms of cost and risk to the astronauts, vehicle, support personnel, and general public. The objective of the present work is to determine the astronaut dynamic response index (DRI), which measures injury risks. Risks are determined for a range of vertical and horizontal landing velocities. A structural model of the crew module (CM) is developed and computational simulations are performed using a transient dynamic simulation analysis code (LS-DYNA) to determine acceleration profiles. Landing acceleration profiles are input in a human factors model that determines astronaut risk levels. Details of the modeling approach, the resulting accelerations, and astronaut risk levels are provided.

Lawrence, Charles; Carney, Kelly S.; Littell, Justin

2007-01-01

305

Multichannel 2 cm receiver for radio-astronomical observations  

NASA Astrophysics Data System (ADS)

An eight-channel receiver for observations in the radio continuum at 2 cm and the polarization characteristics is being developed. The system consists of four hybrid mode feed horns in quadratic array, followed directly by the cooled part. The latter comprises four special conducting directional couplers with low ellipticity, four polarizers, eight three-stage FET amplifiers on the 20 K-station, and eight two-stage amplifiers on the 70 K-station. The eight output channels are postamplified in the uncooled part and mixed down to the ZF band. The left and right circular polarized output channels are correlated in the ZF polarimeter in order to obtain the polarization information. The receiver is also operable with a spectrometer for line observations.

Ruf, K.; Mattes, H.; Pilz, M.; Schmidt, A.

306

Translation Optics for 30 cm Ion Engine Thrust Vector Control  

NASA Technical Reports Server (NTRS)

Data were obtained from a 30 cm xenon ion thruster in which the accelerator grid was translated in the radial plane. The thruster was operated at three different throttle power levels, and the accelerator grid was incrementally translated in the X, Y, and azimuthal directions. Plume data was obtained downstream from the thruster using a Faraday probe mounted to a positioning system. Successive probe sweeps revealed variations in the plume direction. Thruster perveance, electron backstreaming limit, accelerator current, and plume deflection angle were taken at each power level, and for each accelerator grid position. Results showed that the thruster plume could easily be deflected up to six degrees without a prohibitive increase in accelerator impingement current. Results were similar in both X and Y direction.

Haag, Thomas

2002-01-01

307

Gravitational-wave detection using redshifted 21-cm observations  

SciTech Connect

A gravitational-wave traversing the line of sight to a distant source produces a frequency shift which contributes to redshift space distortion. As a consequence, gravitational waves are imprinted as density fluctuations in redshift space. The gravitational-wave contribution to the redshift space power spectrum has a different {mu} dependence as compared to the dominant contribution from peculiar velocities. This, in principle, allows the two signals to be separated. The prospect of a detection is most favorable at the highest observable redshift z. Observations of redshifted 21-cm radiation from neutral hydrogen hold the possibility of probing very high redshifts. We consider the possibility of detecting primordial gravitational waves using the redshift space neutral hydrogen power spectrum. However, we find that the gravitational-wave signal, though present, will not be detectable on superhorizon scales because of cosmic variance and on subhorizon scales where the signal is highly suppressed.

Bharadwaj, Somnath [Department of Physics and Meteorology, I.I.T., Kharagpur, 721302 (India); Centre for Theoretical Studies, I.I.T., Kharagpur, 721302 (India); Guha Sarkar, Tapomoy [Centre for Theoretical Studies, I.I.T., Kharagpur, 721302 (India)

2009-06-15

308

Performance tests for the NASA Ames Research Center 20 cm x 40 cm oscillating flow wind tunnel  

NASA Technical Reports Server (NTRS)

An evaluation is presented of initial tests conducted to assess the performance of the NASA Ames 20 cm x 40 cm oscillating flow wind tunnel. The features of the tunnel are described and two aspects of tunnel operation are discussed. The first is an assessment of the steady mainstream and boundary layer flows and the second deals with oscillating mainstream and boundary layer flows. Experimental results indicate that in steady flow the test section mainstream velocity is uniform in the flow direction and in cross section. The freestream turbulence intensity is about 0.2 percent. With minor exceptions the steady turbulent boundary layer generated on the top wall of the test section exhibits the characteristics of a zero pressure gradient turbulent boundary layer generated on a flat plate. The tunnel was designed to generate sinusoidal oscillating mainstream flows. Experiments confirm that the tunnel produces sinusoidal mainstream velocity variations for the range of frequencies (up to 15 Hz). The results of this study demonstrate that the tunnel essentially produces the flows that it was designed to produce.

Cook, W. J.; Giddings, T. A.

1984-01-01

309

Phase II trial of S-1 and concurrent radiotherapy in patients with locally advanced pancreatic cancer  

Microsoft Academic Search

Purpose  S-1 has a favorable effect in unresectable pancreatic cancer and a potential radiosensitizer. In addition, daily oral administration\\u000a of S-1 is more convenient than continuous infusion of 5-fluorouracil. This study was designed to evaluate the efficacy and\\u000a safety of S-1 and concurrent radiotherapy in patients with locally advanced pancreatic cancer.\\u000a \\u000a \\u000a \\u000a Methods  Eligibility criteria were histologically proven pancreatic adenocarcinoma, locally advanced disease,

Hee Man Kim; Seungmin Bang; Jeong Youp Park; Jinsil Seong; Si Young Song; Jae Bock Chung; Seung Woo Park

2009-01-01

310

Measurement of the caesium 6S1/2?8P1/2 transition frequency  

NASA Astrophysics Data System (ADS)

The caesium 6S1/2?8P1/2,3/2 transitions at 387.6 nm and 388.8 nm have been observed with a linewidth of <5 MHz by laser spectroscopy. The absolute frequency of the 6S1/2?8P1/2 transition was determined to an uncertainty of +/-1 MHz using the calibrated rubidium 5S1/2?5D5/2 two-photon transition and accurate interferometry. The potential of this caesium transition as a useful secondary frequency standard in blue-UV region is discussed.

Liu, Y.-W.; Baird, P. E. G.

311

Chronic myelogenous leukemia after postoperative adjuvant S-1 therapy for rectal cancer: a case report  

PubMed Central

We report a case in which chronic myelogenous leukemia (CML) developed after postoperative adjuvant S-1 therapy for rectal cancer. A 56-year-old man was diagnosed with rectal adenocarcinoma, which was treated with abdominoperineal resection followed by a year of adjuvant S-1 therapy. At 39 postoperative months, he was diagnosed with CML. Although it remains unclear that CML that develops after treatment involving cytotoxic agents is treatment-related, clinicians should be aware of the possibility of CML developing after S-1 therapy.

Manabe, Masahiro; Nishii, Takafumi; Okita, Junya; Nagasaki, Johji; Harada, Naonori; Aoyama, Yasutaka; Kumura, Takeo; Ohta, Tadanobu; Furukawa, Yoshio; Takeuchi, Kazuhiro; Mugitani, Atsuko

2013-01-01

312

Characterization of CdS 1? x Se x thin films by chemical bath deposition technique  

Microsoft Academic Search

The cadmium sulfo selenide CdS1?xSex thin films were chemical bath deposited in aqueous media onto coated glass substrates. As-deposited CdS1?xSex thin films were annealed at 350°C in air for 30min. The structural, morphological, compositional and optical properties of deposited CdS1?xSex thin films were studied using X-ray diffractometer (XRD), scanning electron microscopy (SEM), Energy dispersive analysis by X-ray (EDAX), and UV-Vis-NIR

R. Mariappan; V. Ponnuswamy; M. Ragavendar

313

Enhanced negative thermal expansion in La(1-x)Pr(x)Fe10.7Co0.8Si1.5 compounds by doping the magnetic rare-earth element praseodymium.  

PubMed

Experiments have been performed to enhance negative thermal expansion (NTE) in the La(Fe,Co,Si)13-based compounds by optimizing the chemical composition, i.e., proper substitution of La by magnetic element Pr. It is found that increasing the absolute value of the average coefficient of thermal expansion (CTE) in the NTE temperature region (200-300 K) attributes to enhancement of the spontaneous magnetization and its growth rate with increasing Pr content. Typically, the average CTE of La(1-x)Pr(x)Fe10.7Co0.8Si1.5 with x = 0.5 reaches as large as -38.5 × 10(-6) K(-1) between 200 and 300 K (?T = 100 K), which is 18.5% larger than that of x = 0. The present results highlight the potential applications of La(Fe,Co,Si)13-based compounds with a larger NTE coefficient. PMID:24848739

Li, Wen; Huang, Rongjin; Wang, Wei; Tan, Jie; Zhao, Yuqiang; Li, Shaopeng; Huang, Chuanjun; Shen, Jun; Li, Laifeng

2014-06-01

314

Associated 21-cm absorption towards the cores of radio galaxies  

NASA Astrophysics Data System (ADS)

We present the results of Giant Metrewave Radio Telescope observations to detect H I in absorption towards the cores of a sample of radio galaxies. From observations of a sample of 16 sources, we detect H I in absorption towards the core of only one source, the Fanaroff-Riley type II (FR II) radio galaxy 3C 452 which has been reported earlier by Gupta & Saikia. In this paper we present the results for the remaining sources which have been observed to a similar optical depth as for a comparison sample of compact steep-spectrum (CSS) and gigahertz peaked-spectrum (GPS) sources. We also compile available information on H I absorption towards the cores of extended radio sources observed with angular resolutions of a few arcsec or better. The fraction of extended sources with detection of H I absorption towards their cores is significantly smaller (7/47) than the fraction of H I detection towards CSS and GPS objects (28/49). For the cores of extended sources, there is no evidence of a significant correlation between H I column density towards the cores and the largest linear size of the sources. The distribution of the relative velocity of the principal absorbing component towards the cores of extended sources is not significantly different from that of the CSS and GPS objects. However, a few of the CSS and GPS objects have blueshifted components ?1000 km s-1, possibly due to jet-cloud interactions. With the small number of detections towards cores, the difference in the detection rate between FR I (4/32) and FR II (3/15) sources is within the statistical uncertainties.

Chandola, Yogesh; Gupta, Neeraj; Saikia, D. J.

2013-03-01

315

Preparation of (S)-1-Halo-2-octanols Using Ionic Liquids and Biocatalysts.  

PubMed

Preparation of (S)-1-chloro-2-octanol and (S)-1-bromo-2-octanol was carried out by the enzymatic hydrolysis of halohydrin palmitates using biocatalysts. Halohydrin palmitates were prepared by various methods from palmitic acid and 1,2-octanediol. A tandem hydrolysis was carried out using lipases from Candida antarctica (Novozym 435), Rhizomucor miehei (Lipozyme IM), and "resting cells" from a Rhizopus oryzae strain that was not mycotoxigenic. The influence of the enzyme and the reaction medium on the selective hydrolysis of isomeric mixtures of halohydrin esters is described. Novozym 435 allowed preparation of (S)-1-chloro-2-octanol and (S)-1-bromo-2-octanol after 1-3 h of reaction at 40 degrees C in [BMIM][PF(6)]. PMID:19924063

Oromí-Farrús, Mireia; Eras, Jordi; Sala, Núria; Torres, Mercè; Canela, Ramon

2009-01-01

316

Occurrence of Type S1A Serine Proteases in Sponge and Jellyfish.  

National Technical Information Service (NTIS)

Although serine proteases are found in all kinds of cellular organisms and many viruses, the classic 'chymotrypsin family' (Group S1A by the 1998 Barrett nomenclature) has an unusual phylogenetic distribution, being especially common in animals, entirely ...

A. Rojas R. F. Doolittle

2003-01-01

317

The D{sub s1} and its D*K decays  

SciTech Connect

Recently the Belle Collaboration has measured a new decay channel for the charmed strange meson D{sub s1}(2536){sup +{yields}}D{sup +{pi}-}K{sup +} together with an angular analysis of the D{sub s1}(2536){sup +{yields}}D*{sup +}K{sub S}{sup 0} decay. We study this reaction in a constituent quark model which has been able to reproduce the hadronic phenomenology and the baryon-baryon interaction. The reported branching fraction can be explained through a virtual D*{sup 0} and the properties of the D{sub s1}(2536){sup +} state are nicely reproduced. The influence of other intermediate states in the reaction D{sub s1}(2536){sup +{yields}}D{sup +{pi}-}K{sup +} has been analyzed giving negligible contributions.

Segovia, J.; Entem, D. R.; Fernandez, F. [Nuclear Physics Group and IUFFyM (Spain)

2010-08-05

318

Plastic flow in shock-loaded silver at strain rates from 104 s-1 to 107 s-1 and temperatures from 296 K to 1233 K  

NASA Astrophysics Data System (ADS)

The evolution of elastic-plastic shock waves in 99.9% purity silver samples of 0.127 to 2.0 mm thickness has been studied in a series of VISAR-instrumented planar impact experiments with initial sample temperature varied from 296 to 1233 K. The decay of elastic precursor wave at 933, 1173, and 1233 K temperatures is approximately inversely proportional to the square root of the propagation distance. The latter corresponds to the cubic dependence of initial plastic strain rate, ranged from 104 s-1 to 106 s-1, on the shear stress. At fixed strain rates, the flow stress grows linearly with the temperature but the dependence becomes stronger near the silver melting point, 1234 K. An analysis of the rise times of the plastic shock waves shows that for the same level of shear stress the plastic strain rate at the shock front is significantly higher than that at the top of the elastic precursor wave.

Zaretsky, E. B.; Kanel, G. I.

2011-10-01

319

Thermodynamics of the S = 1 spin ladder as a composite S = 2 chain model  

Microsoft Academic Search

A special class of S=1 spin ladder Hamiltonians, with second-neighbor exchange interactions and with anisotropies in the z-direction, can be mapped onto one-dimensional composite S=2 (tetrahedral S=1) models. We calculate the high temperature expansion of the Helmoltz free energy for the latter class of models, and show that their magnetization behaves closely to that of standard XXZ models with a

Onofre Rojas; E. V. Corrêa Silva; S. M. de Souza; M. T. Thomaz

2005-01-01

320

Thermodynamics of the S=1 spin ladder as a composite S=2 chain model  

Microsoft Academic Search

A special class of S=1 spin ladder Hamiltonians, with second-neighbor exchange interactions and with anisotropies in the z-direction, can be mapped onto one-dimensional composite S=2 (tetrahedral S=1) models. We calculate the high temperature expansion of the Helmoltz free energy for the latter class of models, and show that their magnetization behaves closely to that of standard XXZ models with a

Onofre Rojas; E. V. Corrêa Silva; S. M. de Souza; M. T. Thomaz

2005-01-01

321

S1P receptor mediated activity of FTY720 phosphate mimics.  

PubMed

Various carboxylic acids, phosphonic acids, sulfonic acids, tetrazoles as well as sulfonylhydantoins were prepared as phosphate mimics of the chiral aminophosphate 1-P to act as agonists on the S1P(1) receptor. It was found that amino phosphonates and amino carboxylates are potent S1P(1) binders. beta-Amino acid 11 could be shown to reversibly reduce blood lymphocyte counts in rats after po administration. PMID:20153186

Högenauer, Klemens; Hinterding, Klaus; Nussbaumer, Peter

2010-03-01

322

Combination Therapy with S-1 and Pegylated Interferon Alpha for Advanced Hepatocellular Carcinoma  

Microsoft Academic Search

Purpose: There are currently no effective treatments for patients with advanced hepatocellular carcinoma (HCC) with vascular invasion or extrahepatic metastases. We evaluated the efficacy and safety of combination therapy with S-1 and pegylated interferon (PEG-IFN)-? for advanced HCC. Methods: A total of 22 patients received combination therapy with S-1 and PEG-IFN. One cycle of the combination therapy consists of oral

Kazuomi Ueshima; Masatoshi Kudo; Tomoyuki Nagai; Chie Tatsumi; Taisuke Ueda; Shunsuke Takahashi; Kinuyo Hatanaka; Satoshi Kitai; Emi Ishikawa; Tatsuo Inoue; Satoru Hagiwara; Yasunori Minami; Hobyung Chung

2008-01-01

323

Second generation S1P pathway modulators: research strategies and clinical developments.  

PubMed

Multiple Sclerosis (MS) is a chronic autoimmune disorder affecting the central nervous system (CNS) through demyelination and neurodegeneration. Until recently, major therapeutic treatments have relied on agents requiring injection delivery. In September 2010, fingolimod/FTY720 (Gilenya, Novartis) was approved as the first oral treatment for relapsing forms of MS. Fingolimod causes down-modulation of S1P1 receptors on lymphocytes which prevents the invasion of autoaggressive T cells into the CNS. In astrocytes, down-modulation of S1P1 by the drug reduces astrogliosis, a hallmark of MS, thereby allowing restoration of productive astrocyte communication with other neural cells and the blood brain barrier. Animal data further suggest that the drug directly supports the recovery of nerve conduction and remyelination. In human MS, such mechanisms may explain the significant decrease in the number of inflammatory markers on brain magnetic resonance imaging in recent clinical trials, and the reduction of brain atrophy by the drug. Fingolimod binds to 4 of the 5 known S1P receptor subtypes, and significant efforts were made over the past 5 years to develop next generation S1P receptor modulators and determine the minimal receptor selectivity needed for maximal therapeutic efficacy in MS patients. Other approaches considered were competitive antagonists of the S1P1 receptor, inhibitors of the S1P lyase to prevent S1P degradation, and anti-S1P antibodies. Below we discuss the current status of the field, and the functional properties of the most advanced compounds. This article is part of a Special Issue entitled New Frontiers in Sphingolipid Biology. PMID:24239768

Bigaud, Marc; Guerini, Danilo; Billich, Andreas; Bassilana, Frederic; Brinkmann, Volker

2014-05-01

324

Molecular cloning of a RNA binding protein, S1-1.  

PubMed Central

S1 proteins A-D constitute a nuclear protein family that are liberated rapidly in a set from chromatin by mild digestion with a DNA or RNA hydrolyzing enzyme. With an anti-S1-protein B antiserum that reacted with B2, C1 and D1, a cDNA clone, pS1-1, was obtained, which encoded a protein of 852 amino acids. The S1-1 protein, encoded within the cells by a mRNA of 3480 nt, was a novel protein and could be distinguished from the S1 proteins B, C and D by their amino acid sequences. The S-1-1 protein synthesized by in vitro translation bound to RNA homopolymers, with a preference for G and U polyribonucleotides and little for poly(A). The protein contained two tandem RNP motifs and several intriguing sequences, such as a novel repeat of five octamers with a consensus sequence DP-S(Q/G)YYY and a potentially perfect amphipathic alpha-helix of five turns with basic and acidic amino acids positioned in an ordered way. The two RNP motif sequences were similar, although homologies were low, to the RNP motif sequences of yeast NSR1 protein, animal nucleolins, Drosophila hnRNP Al and tobacco chloroplast RNP precursor protein, suggesting a functional uniqueness of the S1-1 protein in RNA metabolism and also the evolution of its RNP motif structure before plants and animals diverged. These results indicate that the S1-1 protein encoded by the cDNA is a new class of RNA binding protein.

Inoue, A; Takahashi, K P; Kimura, M; Watanabe, T; Morisawa, S

1996-01-01

325

Ceramide and S1P signaling in embryonic stem cell differentiation  

PubMed Central

Summary Recent studies show that bioactive lipids are important regulators for stem cell survival and differentiation. The sphingolipid ceramide and its derivative, sphingosine-1-phosphate (S1P), can act synergistically on embryonic stem (ES) cell differentiation. We show here simple methods to analyze sphingolipids in differentiating ES cells and to use ceramide and S1P analogs for the guided differentiation of mouse ES cells toward neuronal and glial lineage.

Bieberich, Erhard

2013-01-01

326

Phase II study of S-1 in patients with advanced biliary tract cancer  

Microsoft Academic Search

The aim of this study was to investigate the efficacy and safety of an oral fluoropyrimidine derivative, S-1, in patients with advanced biliary tract cancer. Patients with pathologically confirmed advanced biliary tract cancer, a measurable lesion, and no history of radiotherapy or chemotherapy were enrolled. S-1 was administered orally (40 mg m?2 b.i.d.) for 28 days, followed by a 14-day

H Ueno; T Okusaka; M Ikeda; Y Takezako; C Morizane

2004-01-01

327

Molecular cloning of a RNA binding protein, S1-1.  

PubMed

S1 proteins A-D constitute a nuclear protein family that are liberated rapidly in a set from chromatin by mild digestion with a DNA or RNA hydrolyzing enzyme. With an anti-S1-protein B antiserum that reacted with B2, C1 and D1, a cDNA clone, pS1-1, was obtained, which encoded a protein of 852 amino acids. The S1-1 protein, encoded within the cells by a mRNA of 3480 nt, was a novel protein and could be distinguished from the S1 proteins B, C and D by their amino acid sequences. The S-1-1 protein synthesized by in vitro translation bound to RNA homopolymers, with a preference for G and U polyribonucleotides and little for poly(A). The protein contained two tandem RNP motifs and several intriguing sequences, such as a novel repeat of five octamers with a consensus sequence DP-S(Q/G)YYY and a potentially perfect amphipathic alpha-helix of five turns with basic and acidic amino acids positioned in an ordered way. The two RNP motif sequences were similar, although homologies were low, to the RNP motif sequences of yeast NSR1 protein, animal nucleolins, Drosophila hnRNP Al and tobacco chloroplast RNP precursor protein, suggesting a functional uniqueness of the S1-1 protein in RNA metabolism and also the evolution of its RNP motif structure before plants and animals diverged. These results indicate that the S1-1 protein encoded by the cDNA is a new class of RNA binding protein. PMID:8760884

Inoue, A; Takahashi, K P; Kimura, M; Watanabe, T; Morisawa, S

1996-08-01

328

Experimentally Determined Plasma Parameters in a 30 cm Ion Engine  

NASA Technical Reports Server (NTRS)

Single planar Langmuir probes and fiber optic probes are used to concurrently measure the plasma properties and neutral density variation in a 30cm diameter ion engine discharge chamber, from the immediate vicinity of the keeper to the near grid plasma region. The fiber optic probe consists of a collimated optical fiber recessed into a double bore ceramic tube fitted with a stainless steel light-limiting window. The optical fiber probe is used to measure the emission intensity of excited neutral xenon for a small volume of plasma, at various radial and axial locations. The single Langmuir probes, are used to generate current-voltage characteristics at a total of 140 spatial locations inside the discharge chamber. Assuming a maxwellian distribution for the electron population, the Langmuir probe traces provide spatially resolved measurements of plasma potential, electron temperature, and plasma density. Data reduction for the NSTAR TH8 and TH15 throttle points indicates an electron temperature range of 1 to 7.9 eV and an electron density range of 4e10 to le13 cm(sup -3), throughout the discharge chamber, consistent with the results in the literature. Plasma potential estimates, computed from the first derivative of the probe characteristic, indicate potential from 0.5V to 11V above the discharge voltage along the thruster centerline. These values are believed to be excessively high due to the sampling of the primary electron population along the thruster centerline. Relative neutral density profiles are also obtained with a fiber optic probe sampling photon flux from the 823.1 nm excited to ground state transition. Plasma parameter measurements and neutral density profiles will be presented as a function of probe location and engine discharge conditions. A discussion of the measured electron energy distribution function will also be presented, with regards to variation from pure maxwellian. It has been found that there is a distinct primary population found along the thruster centerline, which causes estimates of electron temperature, electron density, and plasma potential, to err on the high side, due this energetic population. Computation of the energy distribution fimction of the plasma clearly indicates the presence of primaries, whose presence become less obvious with radial distance from the main discharge plume.

Sengupta, Anita; Goebel, Dan; Fitzgerald, Dennis; Owens, Al; Tynan, George; Dorner, Russ

2004-01-01

329

Sphingosine-1-phosphate-induced Flk-1 transactivation stimulates mouse embryonic stem cell proliferation through S1P1/S1P3-dependent ?-arrestin/c-Src pathways.  

PubMed

Although recent findings showed that the bioactive lipid metabolites can regulate the ES cell functions, the physiological relevance of interaction between sphingosine-1-phosphate (S1P) and Flk-1 and its related signaling molecules are not yet clear in ES cell proliferation. In the present study, S1P1-5 receptors were expressed in mouse ES cells and S1P increased S1P1-3 receptor expression level. S1P treatment stimulated the cellular proliferation in S1P1/3-dependent manner, located in lipid rafts. In response to S1P, ?-arrestin was recruited to S1P1/3 receptor and c-Src was activated. S1P also increased the binding of S1P1/3 receptor with Flk-1. Similar to responses for VEGF, S1P increased Flk-1 phosphorylation, which was blocked by ?-arrestin siRNA, and PP2, but not by VEGF-A164 antibody or VEGF siRNA. In addition, S1P induced VEGF expression and VEGFR2 kinase inhibitor (SU1498) blocked the S1P-induced cellular proliferation. However, VEGF-A164 antibody or VEGF siRNA partially blocked S1P-induced cellular proliferation, suggesting that both VEGF-dependent Flk-1 activation and VEGF-independent Flk-1 activation are involved in S1P-induced ES cell proliferation. S1P and VEGF-induced phosphorylation of ERK and JNK were blocked by pretreatment with SU1498. Moreover, inhibition of ERK and JNK blocked S1P-induced cellular proliferation. In conclusion, S1P-elicited transactivation of Flk-1 mediated by S1P1/3-dependent ?-arrestin/c-Src pathways stimulated mouse ES cell proliferation. PMID:24145189

Ryu, Jung Min; Baek, Young Bin; Shin, Myung Sun; Park, Ji Hoon; Park, Soo Hyun; Lee, Jang Hern; Han, Ho Jae

2014-01-01

330

S1P and LPA have an attachment-dependent regulatory effect on invasion of epithelial ovarian cancer cells  

Microsoft Academic Search

ObjectivesWe previously demonstrated the regulation of epithelial ovarian cancer (EOC) cell invasiveness by the bioactive phospholipid sphingosine 1-phosphate (S1P). Low-dose S1P stimulated invasion like lysophosphatidic acid (LPA), while high-dose S1P inhibited invasion. Here we investigate how cell attachment status affects response to S1P and examine the effects of S1P and LPA on cell–cell and cell–extracellular matrix (ECM) adhesion.

Yoel Smicun; Orlando Gil; Kate Devine; David A. Fishman

2007-01-01

331

A novel role of sphingosine 1-phosphate receptor S1pr1 in mouse thrombopoiesis  

PubMed Central

Millions of platelets are produced each hour by bone marrow (BM) megakaryocytes (MKs). MKs extend transendothelial proplatelet (PP) extensions into BM sinusoids and shed new platelets into the blood. The mechanisms that control platelet generation remain incompletely understood. Using conditional mutants and intravital multiphoton microscopy, we show here that the lipid mediator sphingosine 1-phosphate (S1P) serves as a critical directional cue guiding the elongation of megakaryocytic PP extensions from the interstitium into BM sinusoids and triggering the subsequent shedding of PPs into the blood. Correspondingly, mice lacking the S1P receptor S1pr1 develop severe thrombocytopenia caused by both formation of aberrant extravascular PPs and defective intravascular PP shedding. In contrast, activation of S1pr1 signaling leads to the prompt release of new platelets into the circulating blood. Collectively, our findings uncover a novel function of the S1P–S1pr1 axis as master regulator of efficient thrombopoiesis and might raise new therapeutic options for patients with thrombocytopenia.

Zhang, Lin; Orban, Martin; Lorenz, Michael; Barocke, Verena; Braun, Daniel; Urtz, Nicole; Schulz, Christian; von Bruhl, Marie-Luise; Tirniceriu, Anca; Gaertner, Florian; Proia, Richard L.; Graf, Thomas; Bolz, Steffen-Sebastian; Montanez, Eloi; Prinz, Marco; Muller, Alexandra; von Baumgarten, Louisa; Billich, Andreas; Sixt, Michael; Fassler, Reinhard; von Andrian, Ulrich H.; Junt, Tobias

2012-01-01

332

S1/S2 excitonic splittings and vibronic coupling in the excited state of the jet-cooled 2-aminopyridine dimer  

NASA Astrophysics Data System (ADS)

We analyze the vibronic band structure of the excitonically coupled S1<--S0/S2<--S0 excitations of the 2-aminopyridine (2AP) self-dimer (2AP)2, using a linear vibronic coupling model [R. Fulton and M. Gouterman, J. Chem. Phys. 41, 2280 (1964)]. The vibronic spectra of supersonically cooled (2AP)2 and its 13C-isotopomer were measured by two-color resonant two-photon ionization and UV/UV-depletion spectroscopies. In the C2-symmetric form of (2AP)2, the S1<--S0 (1A<--1A) transition is very weak, while the close-lying S2<--S0 (1B<--1A) transition is fully allowed. A single 12C/13C isotopic substitution breaks the symmetry of the dimer so that the (2AP)2-13C isotopologue exhibits both S1 and S2 electronic origins, which are split by 11 cm-1. In Fulton-Gouterman-type treatments, the linear vibronic coupling is mediated by intramolecular vibrational modes and couplings to intermolecular vibrations are not considered. For (2AP)2, a major vibronic coupling contribution arises from the intramolecular 6a' vibration. However, the low-energy part of the spectrum is dominated by intermolecular shear (?') and stretching (?') vibrational excitations that also exhibit excitonic splittings; we apply a linear vibronic coupling analysis for these also. The respective excitation transfer integrals VAB are 50%-80% of that of the intramolecular 6a' vibration, highlighting the role of intermolecular vibrations in mediating electronic energy exchange. The S1/S2 electronic energy gap calculated by the approximate second-order coupled-cluster method is ~340 cm-1. This purely electronic exciton splitting is quenched by a factor of 40 by the vibronic couplings to the Franck-Condon active intramolecular vibrations.

Ottiger, Philipp; Leutwyler, Samuel; Köppel, Horst

2009-11-01

333

Sensing and characterization of explosive vapors near 700 cm-1  

NASA Astrophysics Data System (ADS)

One of the technological challenges associated with trace vapor detection of explosive materials are the relatively low vapor pressures exhibited by most energetic materials under ambient conditions. For example, the vapor pressure for TNT is ~10 ppbv at room temperature, a concentration near the Limit of Detection for many of the technologies currently being deployed. In the case of improvised explosive devices, the clandestine nature of the device further serves to exacerbate the vapor pressure issue. Interestingly, the gold standard in explosives detection remains the trained canine nose. While there is still some debate as to what the dog actually smells, recent studies have indicated the alert response is triggered, not by the vapor presence of a specific explosive compound but, by a characteristic bouquet of odors from chemical impurities used to manufacture and process the explosives. Here we present high resolution infrared data for several of these volatile organic compounds in the 700 cm-1 region required for real time optical sensing of energetic materials.

Ford, Alan R.; Reeve, Scott W.

2007-04-01

334

CM and DM in an ISO R and D Environment  

NASA Technical Reports Server (NTRS)

ISO 9000 - a common buzz word in industry is making inroads to government agencies. The National Aeronautics and Space Agency (NASA) achieved ISO 9001 certification at each of its nine (9) Centers and Headquarters in 1998-1999. NASA Glenn Research Center (GRC) was recommended for certification in September 1999. Since then, each of the Centers has been going through the semi-annual surveillance audits. Growing out of the manufacturing industry, successful application of the international quality standard to a research and development (R&D) environment has had its challenges. This paper will address how GRC applied Configuration Management (CM) and Data (or Document) Management (DM) to meet challenges to achieve ISO certification. One of the first challenges was to fit the ISO 9001-1994 elements to the GRC environment. Some of the elements fit well-Management Responsibility (4.1), Internal Audits (4.17), Document and Data Control (4.5). Other elements were not suited or applied easily to the R&D environment-Servicing (4.19), Statistical Techniques (4.20). Since GRC "builds" only one or two items at a time, these elements were considered not applicable to the environment.

Crowley, Sandra L.

2000-01-01

335

Survey of CM Continuum Emission Toward Protostars in Taurus  

NASA Astrophysics Data System (ADS)

We carried out 3.6 cm VLA observations of 17 embedded sources with CO wing emission in Taurus. We detected continuum emission toward 12 embedded sources and 7 were newly detected. Most detected sources are not resolved with 3" beam. The X band emission at the embedded phase likely originates from partially thick thermal free-free emission of ionized jets (e.g. Anglada et al. 1998). Our results indicate that the compact thermal jets (< 100 AU) are ubiquitous phenomena even in low-mass protostars. Although X band fluxes of some detected sources in our study are in agreement with those measured previously, we found that the flux of L1551 NE became stronger by a factor of a few as that in 1994 (Rodriguez et al. 1995). This result suggests that the jet activity, probably related to accretion rate, changed in a few years. We also discuss observations of jets around low-mass protostars with the ALMA array. Anglada, G. et al. 1998, AJ, 116, 2953 Rodriguez, L. F. et al. 1995, ApJ, 454, L149

Saito, Masao; Beltran, Maria T.; Ho, Paul T. P.; Kawabe, Ryohei

1999-10-01

336

Microbiological study of the Murchison CM2 meteorite  

NASA Astrophysics Data System (ADS)

In 1864, Louis Pasteur attempted to cultivate living microorganisms from pristine samples of the Orgueil CI1 carbonaceous meteorite. His results were negative and never published, but recorded it in his laboratory notebooks. At that time, only aerobic liquid or agar-based organic reach media were used, as his research on anaerobes had just started. In our laboratory the Murchison CM2 carbonaceous meteorite was selected to expand on these studies for microbiological study by cultivation on anaerobic mineral media. Since the surface could have been more easily contaminated, interior fragments of a sample of the Murchison meteorite were extracted and crushed under sterile conditions. The resulting powder was then mixed in anoxic medium and injected into Hungate tubes containing anaerobic media with various growth substrates at different pH and salinity and incubated at different temperatures. The goal of the experiments was to determine if living cells would grow from the material of freshly fractured interior fragments of the stone. If any growth occurred, work could then be carried out to assess the nature of the environmental contamination by observations of the culture growth (rates of speed and biodiversity); live/dead fluorescent staining to determine contamination level and DNA analysis to establish the microbial species present. In this paper we report the results of that study.

Pikuta, Elena V.; Hoover, Richard B.

2012-10-01

337

Beam tests of A 2 cm diameter lithium lens  

SciTech Connect

Following the pioneering work on lithium lenses at INP, Novosibirsk, a 2 cm diameter lens was designed and built at Fermilab as an antiproton collector for the antiproton source of the Tevatron I project. A lens of this type was tested at the CERN Antiproton Accumulator (AA) as an antiproton collector and then as a prefocusing element before the AA pulsed current target. In the latter case the purpose was to increase the proton beam convergence at the target to compensate the defocusing effect on the proton beam of the current in the target. As an antiproton collector the lithium lens performed as predicted increasing the antiproton yield into the AA by 40%. In the prefocusing configuration beam convergence and spot size on the target were considerably improved over the standard arrangement using a pulsed quadrupole triplet and the lens has survived 1.4 M pulses of current from 290 to 350 kA in a 26 GeV/c beam of up to 1.4 x 10/sup 13/ protons.

Fiander, D.C.; Dugan, G.; Hojvat, C.; Johnson, C.D.; Lennox, A.; Maury, S.; Sherwood, T.R.

1985-10-01

338

Piezo-Operated Shutter Mechanism Moves 1.5 cm  

NASA Technical Reports Server (NTRS)

The figure shows parts of a shutter mechanism designed to satisfy a number of requirements specific to its original intended application as a component of an atomic clock to be flown in outer space. The mechanism may also be suitable for use in laboratory and industrial vacuum systems on Earth for which there are similar requirements. The requirements include the following: a) To alternately close, then open, a 1.5-cm-diameter optical aperture twice per second, with a stroke time of no more than 15 ms, during a total operational lifetime of at least a year; b) To attenuate light by a factor of at least 1012 when in the closed position; c) To generate little or no magnetic field; d) To be capable of withstanding bakeout at a temperature of 200 C to minimize outgassing during subsequent operation in an ultrahigh vacuum; and e) To fit within a diameter of 12 in. (=305 mm) a size limit dictated by the size of an associated magnetic shield. The light-attenuation requirement is satisfied by use of overlapping shutter blades. The closure of the aperture involves, among other things, insertion of a single shutter blade between a pair of shutter blades. The requirement to minimize the magnetic field is satisfied by use of piezoelectric actuators. Because piezoelectric actuators cannot withstand bakeout, they must be mounted outside the vacuum chamber, and, hence, motion must be transmitted from the actuators to the shutter levers via a vacuum-chamber-wall diaphragm.

Glaser, Robert; Bamford, Robert

2005-01-01

339

Line Broadening Parameters of Methane at 6000 CM^{-1}  

NASA Astrophysics Data System (ADS)

Being one of the most important greenhouse gases, methane (CH_4) is also modified by anthropogenic activity. Nowadays, it can be monitored globally from space on the long-term scale using combinations of different remote sensing instruments. The critical point for the retrieval algorithms is the knowledge of the spectroscopic parameters. Although a significant amount of spectroscopic data on CH_4 is available, the information on the line parameters in mid infrared (MIR) spectral region is inadequate for accurate remote sensing applications and there is a need for improved spectroscopic line parameters. We report on the improved spectroscopic line parameters for CH_4 in the spectral regions used by SCIAMACHY and TANSO instruments around 6000 cm^{-1}. New data were obtained using high resolution absorption spectra of CH_4, perturbed by oxygen, nitrogen and air. Spectra were measured using Fourier transform spectrometer in a broad range of total pressures from 2 to 1000 mbar and temperatures down to 196 K. Calculations of broadening parameters were performed using Reference Forward Model assuming Voigt line profile within international collaboration between the Molecular Spectroscopy Laboratory in IUP Bremen, and Earth Observation Science Group, University of Leicester, UK. Accuracy of the new data matches the level of the demands of modern datasets and remote sensing. The new data were compared with the data included in the latest HITRAN edition and other published works. Before release for the general scientific community, the new data was tested on the TANSO and SCIAMACHY retrievals.

Gorshelev, Victor; Serdyuchenko, Anna; Buchwitz, M.; Burrows, J.; Humpage, Neil; Remedios, J.

2013-06-01

340

Determination of the 243 Cm/244 Cm ratio alpha spectrometry and spectral deconvolution in environmental samples exposed to discharges from the nuclear fuel cycle.  

PubMed

The presence of curium nuclides in irradiated nuclear fuel is well known, as is their occurrence in environmental materials exposed to liquid waste discharges from reprocessing plants and to fallout following the Chernobyl accident. Knowledge of the 242 Cm/244 Cm and 243 Cm/244 Cm atom ratios can be a useful tool for characterizing a source-term and assessing the burn-up history of nuclear fuel. Here, a practical technique, based on high-resolution alpha spectrometry and spectral deconvolution, is described by which the 243, 244 Cm multiplet can be resolved at the low activities typical of most environmental samples. The resulting 243 Cm/244 Cm ratio is then used to correct for any interference by 243 Cm in the 242 Cm window. The technique has been applied to the determination of the 243 Cm/244 Cm ratio in samples of seabed sediment collected near the Sellafield outfall, riverine sediment sampled downstream of the Mayak reprocessing plant and soil and lichen from within the Chernobyl exclusion zone. Near Sellafield, the 243 Cm/244 Cm ratio was found to be < 2%, while near Mayak and Chernobyl it was considerably higher, being approximately 6-8%. PMID:9699290

Mitchell, P I; Holm, E; León Vintró, L; Condren, O M; Roos, P

1998-01-01

341

What Are Space Exposure Histories Telling Us about CM Carbonaceous Chondrites?  

NASA Technical Reports Server (NTRS)

Chondrites are chemically primitive and carbonaceous (C) chondrites are potentially the most primitive among them because they mostly escaped thermal metamor-phism that affected the other chondrite groups and ratios of their major, non-volatile and most of the volatile elements are similar to those of the Sun. Therefore, C chondrites are ex-pected to retain a good record of the origin and early history of the solar system. Carbonaceous chondrites are chemically differentiated from other chondrites by their high Mg/Si ratios and refractory elements, and have experienced various degrees of aqueous alteration. They are subdivided into eight subgroups (CI, CM, CO, CV, CK, CR, CB and CH) based on major element and oxygen isotopic ratios. Their elemental ratios spread over a wide range though those of ordinary and enstatite chondrites are relatively uniform. It is critical to know how many sepa-rate bodies are represented by the C chondrites. In this study, CM chondrites, the most abundant carbona-ceous chondrites, are examined. They are water-rich, chon-drule- and CAI-bearing meteorites and most of them are brec-cias. High-temperature components such as chondrules, iso-lated olivine and CAIs in CMs are frequently altered and some of them are replaced by clay minerals and surrounded by sul-fides whose Fe was derived from mafic silicates. On the basis of degrees of aqueous alteration, CMs have been classified into subtypes from 1 to 2, although Rubin et al. [1] assigned subtype 1 to subtype 2 and subtype 2 to subtype 2.6 using various petrologic properties. The classification is based on petrographic and mineralogic properties. For example, though tochilinite (2[(Fe, Mg, Cu, Ni[])S] 1.57-1.85 [(Mg, Fe, Ni, Al, Ca)(HH)2]) clumps are produced during aqueous alteration, they disappear and sulfide appears with increasing degrees of aqueous alteration. Cosmic-ray exposure (CRE) age measurements of CM chondrites reveal an unusual feature. Though CRE ages of other chondrite groups range from several Myr to tens of Myr, CMs exposure ages are not longer than 7 Myr with one-third of the CM having less than 1 Myr CRE age. For those CM chondrites that have CRE ages <1 Myr, there are two discern-able CRE peaks. Because a CRE age reflects how long a me-teorite is present as a separate body in space, the peaks pre-sumably represent collisional events on the parent body (ies) [2]. In this study we defined 4 distinct CRE age groups of CMs and systematically characterized the petrography in each of the 4 CRE age groups to determine whether the groups have significant petrographic differences, with such differences probably reflecting different parent body (asteroid) geological processing, or multiple original bodies.

Takenouchi, A.; Zolensky, Michael E.; Nishiizumi, K.; Caffee, M.; Velbel, M. A.; Ross, K.; Zolensky, P.; Le, L.; Imae, N.; Yamaguchi, A.; Mikouchi, T.

2013-01-01

342

Characterizing the Dust Coma of Comet C/2012 S1 (ISON) at 4.15 AU from the Sun  

NASA Astrophysics Data System (ADS)

We report results from broadband visible images of comet C/2012 S1 (ISON) obtained with the Hubble Space Telescope Wide Field Camera 3 on 2013 April 10. C/ISON's coma brightness follows a 1/? (where ? is the projected distance from the nucleus) profile out to 5000 km, consistent with a constant speed dust outflow model. The turnaround distance in the sunward direction suggests that the dust coma is composed of sub-micron-sized particles emitted at speeds of tens of m s-1. A(?)f?, which is commonly used to characterize the dust production rate, was 1340 and 1240 cm in the F606W and F438W filters, respectively, in apertures <1.''6 in radius. The dust colors are slightly redder than solar, with a slope of 5.0% ± 0.2% per 100 nm, increasing to >10% per 100 nm 10,000 km down the tail. The colors are similar to those of comet C/1995 O1 (Hale-Bopp) and other long-period comets, but somewhat bluer than typical values for short-period comets. The spatial color variations are also reminiscent of C/Hale-Bopp. A sunward jet is visible in enhanced images, curving to the north and then tailward in the outer coma. The 1.''6 long jet is centered at a position angle of 291°, with an opening angle of ~45°. The jet morphology remains unchanged over 19 hr of our observations, suggesting that it is near the rotational pole of the nucleus, and implying that the pole points to within 30° of (R.A., decl.) = (330°, 0°). This pole orientation indicates a high obliquity of 50°-80°.

Li, Jian-Yang; Kelley, Michael S. P.; Knight, Matthew M.; Farnham, Tony L.; Weaver, Harold A.; A'Hearn, Michael F.; Mutchler, Max J.; Kolokolova, Ludmilla; Lamy, Philippe; Toth, Imre

2013-12-01

343

Iron Oxides and Magnetic Parameters At The Active Oxidation Front of Sapropel S1 In The Eastern Mediterranean  

NASA Astrophysics Data System (ADS)

Sapropels are deposited under anoxic conditions. Upon re-establishing of oxic condi- tions in the water column the sapropels oxidise, starting at their tops. The oxidation process involves re-allocation of iron over various oxidic and sulphidic phases. In the present study these were analysed geochemically - employing the sequential extrac- tion scheme described in Rutten et al. (2001) - and mineral magnetically. The study focuses on S1, the youngest sapropel, recovered from a 41 cm long boxcore from the Eastern Mediterranean (3615.85'N; 2148.38'E). S1 ranges from 25 centimetres subbottom depth to the bottom of the boxcore. Emphasis was put on the assessment of the behaviour of the oxidised part of the sapropel, the zone of active oxidation, and the upper part of the still anoxic and visible sapropel. Iron is allocated over various silicates (the most important mineralogical phases), pyrite (in the anoxic part of the sapropel), and detrital and diagenetic oxide phases. The diagenetic iron oxides dom- inantly occur in the oxidised sapropel part. They are very fine-grained making them amenable to analysis by means of sequential extraction and mineral-magnetic meth- ods. Iron appeared to hardly extract during the carbonate dissolution steps. During the following 'amorphous oxide' extraction step the bulk of the oxidic iron is indeed dissolved together with a distinct amount of Si4+ suggesting that most of the diage- netic iron occurs as coatings around silicates. Pyrite is evidently only traced in the anoxic part of the sapropel. Mineral-magnetic analysis involved component analysis of the isothermal remanent magnetisation (IRM, cf. Kruiver et al., 2001; Heslop et al., 2002) and hysteresis loop measurements. This was done on untreated sediment, and after several steps of the extraction scheme. Three coercivity phases could be iden- tified, interpreted as detrital magnetite, biogenic magnetite, and hematite. Hysteresis measurements indicate the importance of bacterial magnetite in the oxidised sapropel, particularly in the active oxidation zone.

Garming, J. F. L.; de Lange, G. J.; Dekkers, M. J.; Passier, H. F.

344

Evaluation of Inpatient Clinical Documentation Readiness for ICD-10-CM.  

PubMed

This research study examined the gaps in documentation that occur when coding in ICD-10-CM. More than 4,000 diagnoses from all chapters were coded from 656 electronic documents obtained from a large integrated healthcare facility at the time the study was conducted (2012). After the documents were coded, areas for documentation improvement were identified for chapters that resulted in deficiencies in documentation, and a quick reference guide was developed. The overall absent documentation percentage was 15.4 percent. The 10 chapters with the highest percentage of absent documentation were chapter 7 (Diseases of Eye and Adnexa), with 67.65 percent (p < .001); chapter 8 (Diseases of Ear and Mastoid Process), with 63.64 percent (p < .001); chapter 13 (Diseases of the Musculoskeletal System and Connective Tissue), with 46.05 percent (p < .001); chapter 14 (Diseases of the Genitourinary System), with 40.29 percent (p < .001); chapter 10 (Diseases of Respiratory System), with 35.52 percent (p < .001); chapter 1 (Infectious and Parasitic Diseases), with 32.88 percent (p < .001); chapter 12 (Diseases of the Skin and Subcutaneous Tissue), with 32.35 percent (p < .001); chapter 2 (Neoplasms), with 25.45 percent (p < .001); chapter 4 (Endocrine, Nutritional and Metabolic Diseases), with 14.58 percent (p < .001); and chapter 17 (Congenital Malformations, Deformations, and Chromosomal Abnormalities), with 12.50 percent. We addressed the deficient areas in the quick reference guide developed for clinicians and technology vendors. Having complete and accurate documentation would benefit both the clinician and the patient in providing the highest quality of care. PMID:24808815

Dealmeida, Dilhari R; Watzlaf, Valerie J; Anania-Firouzan, Patti; Salguero, Otto; Rubinstein, Elaine; Abdelhak, Mervat; Parmanto, Bambang

2014-01-01

345

Evaluation of Inpatient Clinical Documentation Readiness for ICD-10-CM  

PubMed Central

This research study examined the gaps in documentation that occur when coding in ICD-10-CM. More than 4,000 diagnoses from all chapters were coded from 656 electronic documents obtained from a large integrated healthcare facility at the time the study was conducted (2012). After the documents were coded, areas for documentation improvement were identified for chapters that resulted in deficiencies in documentation, and a quick reference guide was developed. The overall absent documentation percentage was 15.4 percent. The 10 chapters with the highest percentage of absent documentation were chapter 7 (Diseases of Eye and Adnexa), with 67.65 percent (p < .001); chapter 8 (Diseases of Ear and Mastoid Process), with 63.64 percent (p < .001); chapter 13 (Diseases of the Musculoskeletal System and Connective Tissue), with 46.05 percent (p < .001); chapter 14 (Diseases of the Genitourinary System), with 40.29 percent (p < .001); chapter 10 (Diseases of Respiratory System), with 35.52 percent (p < .001); chapter 1 (Infectious and Parasitic Diseases), with 32.88 percent (p < .001); chapter 12 (Diseases of the Skin and Subcutaneous Tissue), with 32.35 percent (p < .001); chapter 2 (Neoplasms), with 25.45 percent (p < .001); chapter 4 (Endocrine, Nutritional and Metabolic Diseases), with 14.58 percent (p < .001); and chapter 17 (Congenital Malformations, Deformations, and Chromosomal Abnormalities), with 12.50 percent. We addressed the deficient areas in the quick reference guide developed for clinicians and technology vendors. Having complete and accurate documentation would benefit both the clinician and the patient in providing the highest quality of care.

DeAlmeida, Dilhari R.; Watzlaf, Valerie J.; Anania-Firouzan, Patti; Salguero, Otto; Rubinstein, Elaine; Abdelhak, Mervat; Parmanto, Bambang

2014-01-01

346

Isolation of New Stenotrophomonas Bacteriophages and Genomic Characterization of Temperate Phage S1?  

PubMed Central

Twenty-two phages that infect Stenotrophomonas species were isolated through sewage enrichment and prophage induction. Of them, S1, S3, and S4 were selected due to their wide host ranges compared to those of the other phages. S1 and S4 are temperate siphoviruses, while S3 is a virulent myovirus. The genomes of S3 and S4, about 33 and 200 kb, were resistant to restriction digestion. The lytic cycles lasted 30 min for S3 and about 75 min for S1 and S4. The burst size for S3 was 100 virions/cell, while S1 and S4 produced about 75 virus particles/cell. The frequency of bacteriophage-insensitive host mutants, calculated by dividing the number of surviving colonies by the bacterial titer of a parallel, uninfected culture, ranged between 10?5 and 10?6 for S3 and 10?3 and 10?4 for S1 and S4. The 40,287-bp genome of S1 contains 48 open reading frames (ORFs) and 12-bp 5? protruding cohesive ends. By using a combination of bioinformatics and experimental evidence, functions were ascribed to 21 ORFs. The morphogenetic and lysis modules are well-conserved, but no lysis-lysogeny switch or DNA replication gene clusters were recognized. Two major clusters of genes with respect to transcriptional orientation were observed. Interspersed among them were lysogenic conversion genes encoding phosphoadenosine phosphosulfate reductase and GspM, a protein involved in the general secretion system II. The attP site of S1 may be located within a gene that presents over 75% homology to a Stenotrophomonas chromosomal determinant.

Garcia, Pilar; Monjardin, Cristina; Martin, Rebeca; Madera, Carmen; Soberon, Nora; Garcia, Eva; Meana, Alvaro; Suarez, Juan E.

2008-01-01

347

Detection of hepatitis B virus PreS1 antigen using a time-resolved fluoroimmunoassay.  

PubMed

The hepatitis B virus (HBV) PreS1 antigen is expressed at the distal most region of the envelope protein and contains the hepatocyte receptor-binding site. The presence of the HBV PreS1 antigen in serum and liver of HBsAg-positive patients is a new marker used for diagnosing HBV infection, and is indicative of viral replication. Our objective is to establish a method of time-resolved fluoroimmunoassay (TRFIA) with higher sensitivity and broader detection range for detecting serum HBV PreS1 antigen. Eu(3+) labeling of antibodies was performed with respective labeling kits, and Eu(3+) fluorescence intensity was measured with an auto DELFIA1235 TRFIA analyzer. The established method was evaluated for its performance. Serum specimens (574 in total) from Wuxi People's Hospital were analyzed for PreS1 antigen using the TRFIA and ELISA. The precision, specificity, and sensitivity of the TRFIA were clearly better than ELISA. The detection limit was 0.01 ng/mL. The average recovery rate for PreS1 antigens was 103.3%. There was significant correlation between the PreS1 antigen results obtained by TRFIA and ELISA in 374 serum samples with HBV >10(3) IU/mL (?(2) = 25.04, p < 0.01) and 183 HbeAg-positive serum samples (?(2) = 12.07, p < 0.01). Normal reference ranges were established at 0-0.32 ng/mL based on the values obtained from 100 healthy controls. TRFIA is a significantly effective method for clinical detection of serum HBV PreS1 antigens. PMID:22471606

Hu, Zhigang; Li, Mei; Huang, Biao; Liu, Jie; Yu, Lei; Chen, Guoqian

2012-01-01

348

Isolation of new Stenotrophomonas bacteriophages and genomic characterization of temperate phage S1.  

PubMed

Twenty-two phages that infect Stenotrophomonas species were isolated through sewage enrichment and prophage induction. Of them, S1, S3, and S4 were selected due to their wide host ranges compared to those of the other phages. S1 and S4 are temperate siphoviruses, while S3 is a virulent myovirus. The genomes of S3 and S4, about 33 and 200 kb, were resistant to restriction digestion. The lytic cycles lasted 30 min for S3 and about 75 min for S1 and S4. The burst size for S3 was 100 virions/cell, while S1 and S4 produced about 75 virus particles/cell. The frequency of bacteriophage-insensitive host mutants, calculated by dividing the number of surviving colonies by the bacterial titer of a parallel, uninfected culture, ranged between 10(-5) and 10(-6) for S3 and 10(-3) and 10(-4) for S1 and S4. The 40,287-bp genome of S1 contains 48 open reading frames (ORFs) and 12-bp 5' protruding cohesive ends. By using a combination of bioinformatics and experimental evidence, functions were ascribed to 21 ORFs. The morphogenetic and lysis modules are well-conserved, but no lysis-lysogeny switch or DNA replication gene clusters were recognized. Two major clusters of genes with respect to transcriptional orientation were observed. Interspersed among them were lysogenic conversion genes encoding phosphoadenosine phosphosulfate reductase and GspM, a protein involved in the general secretion system II. The attP site of S1 may be located within a gene that presents over 75% homology to a Stenotrophomonas chromosomal determinant. PMID:18952876

García, Pilar; Monjardín, Cristina; Martín, Rebeca; Madera, Carmen; Soberón, Nora; Garcia, Eva; Meana, Alvaro; Suárez, Juan E

2008-12-01

349

Transarterial infusion chemotherapy with cisplatin plus S-1 for hepatocellular carcinoma treatment: a phase I trial  

PubMed Central

Background In Japan, transarterial infusion chemotherapy using cisplatin (CDDP-TAI) is frequently used for advanced hepatocellular carcinoma (HCC). Moreover, oral chemotherapy with S-1, an oral fluoropyrimidine derivative, has also elicited promising responses in HCC patients. We determined the recommended dosage for CDDP-TAI plus S-1 combination therapy for advanced HCC. Methods Twelve Child–Pugh class A or B patients with advanced HCC who met the eligibility criteria were enrolled in this phase I trial. Patients received CDDP-TAI (infusion, day 1) plus S-1 (oral administration, days 1–21) every 5 weeks until disease progression. Results Cisplatin (65 mg/m2) was administered with S-1 at 50 mg?·?m-2 day-1 (level 1, 3 patients), 60 mg?·?m-2 day-1 (level 2, 3 patients), or 80 mg?·?m-2 day-1 (level 3, 6 patients). The total number of treatment courses was 25 (median, 2 courses/patient; range, 1–6 courses). Dose-limiting toxicity was not observed in any patient at any level; therefore, the recommended dosage for cisplatin and S-1 in combination was level 3. Grade 3 adverse events were elevated alanine aminotransferase levels (2 patients), elevated aspartate aminotransferase levels (2 patients), anemia (1 patient), and decreased platelet counts (1 patient). Median progression-free survival and overall survival were 73 days and 328 days, respectively. The disease control rate was 58% (7/12); 17% (2/12) of patients achieved partial response and 42% (5/12) achieved stable disease. CDDP-TAI plus S-1 is safe for the treatment of HCC. Conclusion The recommended dosage for further evaluation of this combination therapy in phase II studies is 65 mg/m2 CDDP and 80 mg/m2 S-1. Trial registration UMIN; number: UMIN000003113

2014-01-01

350

S1pr2/G?13 signaling controls myocardial migration by regulating endoderm convergence  

PubMed Central

A key process during vertebrate heart development is the migration of bilateral populations of myocardial precursors towards the midline to form the primitive heart tube. In zebrafish, signaling mediated by sphingosine-1-phosphate (S1P) and its cognate G protein-coupled receptor (S1pr2/Mil) is essential for myocardial migration, but the underlying mechanisms remain undefined. Here, we show that suppression of G?13 signaling disrupts myocardial migration, leading to the formation of two bilaterally located hearts (cardia bifida). Genetic studies indicate that G?13 acts downstream of S1pr2 to regulate myocardial migration through a RhoGEF-dependent pathway. Furthermore, disrupting any component of the S1pr2/G?13/RhoGEF pathway impairs endoderm convergence during segmentation, and the endodermal defects correlate with the extent of cardia bifida. Moreover, endoderm transplantation reveals that the presence of wild-type anterior endodermal cells in G?13-deficient embryos is sufficient to rescue the endoderm convergence defect and cardia bifida, and, conversely, that the presence of anterior endodermal cells defective for S1pr2 or G?13 in wild-type embryos causes such defects. Thus, S1pr2/G?13 signaling probably acts in the endoderm to regulate myocardial migration. In support of this notion, cardiac-specific expression of G?13 fails to rescue cardia bifida in the context of global G?13 inhibition. Our data demonstrate for the first time that the G?13/RhoGEF-dependent pathway functions downstream of S1pr2 to regulate convergent movement of the endoderm, an event that is crucial for coordinating myocardial migration.

Ye, Ding; Lin, Fang

2013-01-01

351

Involvement of Sphingosine 1-Phosphate (SIP)/S1P3 Signaling in Cholestasis-Induced Liver Fibrosis  

PubMed Central

Bioactive sphingosine 1-phosphate (S1P) and S1P receptors (S1PRs) have been implicated in many critical cellular events, including inflammation, cancer, and angiogenesis. However, the role of S1P/S1PR signaling in the pathogenesis of liver fibrosis has not been well documented. In this study, we found that S1P levels and S1P3 receptor expression in liver tissue were markedly up-regulated in a mouse model of cholestasis-induced liver fibrosis. In addition, the S1P3 receptor was also expressed in green fluorescent protein transgenic bone marrow (BM)-derived cells found in the damaged liver of transplanted chimeric mice that underwent bile duct ligation. Silencing of S1P3 expression significantly inhibited S1P-induced BM cell migration in vitro. Furthermore, a selective S1P3 receptor antagonist, suramin, markedly reduced the number of BM-derived cells during cholestasis. Interestingly, suramin administration clearly ameliorated bile duct ligation-induced hepatic fibrosis, as demonstrated by attenuated deposition of collagen type I and III, reduced smooth muscle ?-actin expression, and decreased total hydroxyproline content. In conclusion, our data suggest that S1P/S1P3 signaling plays an important role in cholestasis-induced liver fibrosis through mediating the homing of BM cells. Modulation of S1PR activity may therefore represent a new antifibrotic strategy.

Li, Changyong; Jiang, Xiangming; Yang, Lin; Liu, Xihong; Yue, Shi; Li, Liying

2009-01-01

352

Density functional solvation model based on CM2 atomic charges  

NASA Astrophysics Data System (ADS)

We extend the SM5 solvation model for calculating solvation free energies of a variety of organic solutes in both aqueous and organic solvents so that it can be employed in conjunction with high-level electronic structure calculations. The extension is illustrated by presenting three implementations based on density-functional theory (DFT). The three implementations are called SM5.42R/BPW91/MIDI!6D, SM5.42R/BPW91/DZVP, and SM5.42R/BPW91/6-31G*. They have the following features: (1) They utilize gradient-corrected DFT with polarized double zeta basis sets to describe the electronic structure of a solute. The particular exchange-correlation functional adopted is Becke's exchange with the Perdew-Wang 1991 correlation functional, usually called BPW91. The MIDI!6D, DZVP, and 6-31G* basis sets are used. (2) They employ fixed solute geometries in solvation calculations. The model is designed to predict solvation free energies based on any reasonably accurate gas-phase solute geometry. (3) The electric polarization in the solute-solvent system is described by the generalized Born approximation with self-consistent reaction-field solute partial atomic charges obtained from the CM2 class IV charge model. (4) The solvation effects within the first solvation shell are included in the form of SM5-type atomic surface tensions. Both DFT parameterizations are developed using 275 neutral solutes and 49 ions with gas-phase Hartree-Fock/MIDI! geometries. These solutes contain a wide variety of organic functional groups which include H, C, N, O, F, P, S, Cl, Br, and I atoms. For 2135 free energies of solvation of the neutral molecules in water and 90 organic solvents, SM5.42R/BPW91/MIDI!6D, SM5.42R/BPW91/DZVP, and SM5.42R/BPW91/6-31G* yield mean unsigned errors in solvation free energies of 0.45 kcal/mol, 0.44 kcal/mol, and 0.43 kcal/mol, respectively. For 49 ions in water, SM5.42R/BPW91/MIDI!6D produces a mean unsigned error of 3.9 kcal/mol, while SM5.42R/BPW91/DZVP and SM5.42R/BPW91/6-31G* give 3.6 kcal/mol and 3.9 kcal/mol, respectively.

Zhu, Tianhai; Li, Jiabo; Hawkins, Gregory D.; Cramer, Christopher J.; Truhlar, Donald G.

1998-11-01

353

Magnetic phases in the S =1 Shastry-Sutherland model with uniaxial anisotropy  

NASA Astrophysics Data System (ADS)

We explore the field-induced magnetic phases of an S =1 XXZ model with single-ion anisotropy and large Ising-like anisotropy on a Shastry-Sutherland lattice over a wide range of Hamiltonian parameters and applied magnetic field. The multitude of ground-state phases are characterized in detail in terms of their thermodynamic properties, and the underlying classical (Ising limit) spin arrangements for the plateau phases are identified by calculating the static structure factors. The enlarged local Hilbert space of the S =1 spins results in several ground state phases that are not realized for S =1/2 spins. These include the quantum paramagnetic state that is ubiquitous to S =1 spins with single-ion anisotropy, two different spin supersolid phases (with distinct longitudinal ordering), and a magnetization plateau that arises as a direct descendant of the 1/3 plateau due to quantum fluctuations that are not possible for S =1/2 spins. We predict the same mechanism will lead to plateaus at smaller fractions of 1/3 for higher spins. The full momentum dependence of the longitudinal and transverse components of the static structure factor is calculated in the spin supersolid phase to demonstrate the simultaneous existence of diagonal and off-diagonal long-range order as well as the different longitudinal orderings.

Su, Lei; Wierschem, Keola; Sengupta, Pinaki

2014-06-01

354

S1 is associated with chronic low back pain: a functional and structural MRI study  

PubMed Central

A fundamental characteristic of neural circuits is the capacity for plasticity in response to experience. Neural plasticity is associated with the development of chronic pain disorders. In this study, we investigated 1) brain resting state functional connectivity (FC) differences between patients with chronic low back pain (cLBP) and matched healthy controls (HC); 2) FC differences within the cLBP patients as they experienced different levels of endogenous low back pain evoked by exercise maneuvers, and 3) morphometric differences between cLBP patients and matched HC. We found the dynamic character of FC in the primary somatosensory cortex (S1) in cLBP patients, i.e., S1 FC decreased when the patients experienced low intensity LBP as compared with matched healthy controls, and FC at S1 increased when cLBP patients experienced high intensity LBP as compared with the low intensity condition. In addition, we also found increased cortical thickness in the bilateral S1 somatotopically associated with the lower back in cLBP patients as compared to healthy controls. Our results provide evidence of structural plasticity co-localized with areas exhibiting FC changes in S1 in cLBP patients.

2013-01-01

355

A triplet repeat expansion genetic mouse model of infantile spasms syndrome, Arx(GCG)10+7, with interneuronopathy, spasms in infancy, persistent seizures, and adult cognitive and behavioral impairment.  

PubMed

Infantile spasms syndrome (ISS) is a catastrophic pediatric epilepsy with motor spasms, persistent seizures, mental retardation, and in some cases, autism. One of its monogenic causes is an insertion mutation [c.304ins (GCG)(7)] on the X chromosome, expanding the first polyalanine tract of the interneuron-specific transcription factor Aristaless-related homeobox (ARX) from 16 to 23 alanine codons. Null mutation of the Arx gene impairs GABA and cholinergic interneuronal migration but results in a neonatal lethal phenotype. We developed the first viable genetic mouse model of ISS that spontaneously recapitulates salient phenotypic features of the human triplet repeat expansion mutation. Arx((GCG)10+7) ("Arx plus 7") pups display abnormal spasm-like myoclonus and other key EEG features, including multifocal spikes, electrodecremental episodes, and spontaneous seizures persisting into maturity. The neurobehavioral profile of Arx mutants was remarkable for lowered anxiety, impaired associative learning, and abnormal social interaction. Laminar decreases of Arx+ cortical interneurons and a selective reduction of calbindin-, but not parvalbumin- or calretinin-expressing interneurons in neocortical layers and hippocampus indicate that specific classes of synaptic inhibition are missing from the adult forebrain, providing a basis for the seizures and cognitive disorder. A significant reduction of calbindin-, NPY (neuropeptide Y)-expressing, and cholinergic interneurons in the mutant striatum suggest that dysinhibition within this network may contribute to the dyskinetic motor spasms. This mouse model narrows the range of critical pathogenic elements within brain inhibitory networks essential to recreate this complex neurodevelopmental syndrome. PMID:19587282

Price, Maureen G; Yoo, Jong W; Burgess, Daniel L; Deng, Fang; Hrachovy, Richard A; Frost, James D; Noebels, Jeffrey L

2009-07-01

356

A Triplet Repeat Expansion Genetic Mouse Model of Infantile Spasms Syndrome, Arx(GCG)10+7, with Interneuronopathy, Spasms in Infancy, Persistent Seizures, and Adult Cognitive and Behavioral Impairment  

PubMed Central

Infantile spasms syndrome (ISS) is a catastrophic pediatric epilepsy with motor spasms, persistent seizures, mental retardation, and in some cases, autism. One of its monogenic causes is an insertion mutation (c.304ins (GCG)7) on the X chromosome, expanding the first polyalanine tract of the interneuron-specific transcription factor ARX from 16 to 23 alanine codons. Null mutation of the Arx gene impairs GABA- and cholinergic interneuronal migration but results in a neonatal lethal phenotype. We developed the first viable genetic mouse model of ISS that spontaneously recapitulates salient phenotypic features of the human triplet-repeat expansion mutation. Arx (GCG)10+7 (“Arx Plus7”) pups display abnormal spasm-like myoclonus and other key EEG features, including multifocal spikes, electrodecremental episodes, and spontaneous seizures persisting into maturity. The neurobehavioral profile of Arx mutants was remarkable for lowered anxiety, impaired associative learning, and abnormal social interaction. Laminar decreases of Arx+ cortical interneurons and a selective reduction of calbindin-, but not parvalbumin- or calretinin-expressing interneurons in neocortical layers and hippocampus indicate that specific classes of synaptic inhibition are missing from the adult forebrain, providing a basis for the seizures and cognitive disorder. A significant reduction of calbindin, NPY-expressing and cholinergic interneurons in the mutant striatum suggest that dysinhibition within this network may contribute to the dyskinetic motor spasms. This mouse model narrows the range of critical pathogenic elements within brain inhibitory networks essential to recreate this complex neurodevelopmental syndrome.

Price, Maureen G.; Yoo, Jong W.; Burgess, Daniel L.; Deng, Fang; Hrachovy, Richard A.; Frost, James D.; Noebels, Jeffrey L.

2009-01-01

357

Successful Chemotherapy with Carboplatin and S-1 for Thymic Carcinoma: A Case Report  

PubMed Central

Thymic carcinoma is a rare but aggressive neoplasm. Although there is no clearly optimal first- or second-line chemotherapy regimen for thymic carcinoma, platinum-based chemotherapy has repeatedly been shown to be of benefit to patients with advanced thymic carcinoma. Some case reports have described S-1 as a novel agent with good activity against advanced thymic carcinoma. A 74-year-old female was diagnosed with thymic carcinoma complicated by pleural dissemination and pericardial effusion of carcinomatosa. She was treated with carboplatin on day 1 plus S-1 on days 1–14 in cycles repeated every 3 or 4 weeks. Four cycles of this regimen were administered, and a partial response was confirmed. There were no severe hematological or nonhematological toxicities, and no dose reduction was necessary. To our knowledge, this is the first report to demonstrate the efficacy of combination chemotherapy consisting of carboplatin and S-1 against thymic carcinoma.

Igawa, Satoshi; Yanagisawa, Nobuyuki; Ishihara, Mikiko; Kimura, Michiko; Maki, Sachiyo; Otani, Sakiko; Sasaki, Jiichiro; Masuda, Noriyuki

2013-01-01

358

Direct VLBI detection of the magnetosphere surrounding the young star S1 in Rho Ophiuchi  

NASA Technical Reports Server (NTRS)

VLBI 6-mm data are presently used to investigate the circularly polarized radio core previously identified around the young B3 star S1 in Rho Ophiuchi. The measured angular diameter and brightness temperature are found to be consistent with gyrosynchrotrom radiation emission from mildly relativistic electrons. A simple model based on a pole-on dipolar magnetic field of about 2 kG at the stellar surface suggests itself as consistent with the main observed features of the S1 magnetosphere; an important feature of the model is its taking the influence of the X-ray-emitting plasma into account. S1 may represent a new type of young stellar object, characterized by very extended magnetic fields.

Andre, Philippe; Phillips, Robert B.; Lestrade, Jean-Francois; Klein, Karl-Ludwig

1991-01-01

359

S1 and KH Domains of Polynucleotide Phosphorylase Determine the Efficiency of RNA Binding and Autoregulation  

PubMed Central

To better understand the roles of the KH and S1 domains in RNA binding and polynucleotide phosphorylase (PNPase) autoregulation, we have identified and investigated key residues in these domains. A convenient pnp::lacZ fusion reporter strain was used to assess autoregulation by mutant PNPase proteins lacking the KH and/or S1 domains or containing point mutations in those domains. Mutant enzymes were purified and studied by using in vitro band shift and phosphorolysis assays to gauge binding and enzymatic activity. We show that reductions in substrate affinity accompany impairment of PNPase autoregulation. A remarkably strong correlation was observed between ?-galactosidase levels reflecting autoregulation and apparent KD values for the binding of a model RNA substrate. These data show that both the KH and S1 domains of PNPase play critical roles in substrate binding and autoregulation. The findings are discussed in the context of the structure, binding sites, and function of PNPase.

Wong, Alexander G.; McBurney, Kristina L.; Thompson, Katharine J.; Stickney, Leigh M.

2013-01-01

360

S1 and KH domains of polynucleotide phosphorylase determine the efficiency of RNA binding and autoregulation.  

PubMed

To better understand the roles of the KH and S1 domains in RNA binding and polynucleotide phosphorylase (PNPase) autoregulation, we have identified and investigated key residues in these domains. A convenient pnp::lacZ fusion reporter strain was used to assess autoregulation by mutant PNPase proteins lacking the KH and/or S1 domains or containing point mutations in those domains. Mutant enzymes were purified and studied by using in vitro band shift and phosphorolysis assays to gauge binding and enzymatic activity. We show that reductions in substrate affinity accompany impairment of PNPase autoregulation. A remarkably strong correlation was observed between ?-galactosidase levels reflecting autoregulation and apparent KD values for the binding of a model RNA substrate. These data show that both the KH and S1 domains of PNPase play critical roles in substrate binding and autoregulation. The findings are discussed in the context of the structure, binding sites, and function of PNPase. PMID:23457244

Wong, Alexander G; McBurney, Kristina L; Thompson, Katharine J; Stickney, Leigh M; Mackie, George A

2013-05-01

361

Maize Mitochondrial Plasmid S-1 Sequences Share Homology with Chloroplast Gene psbA  

PubMed Central

The linear, 6397-base pair (bp), mitochondrial S-1 DNA molecule from maize contains a 420-bp segment that is homologous with the chloroplast gene (psbA) that codes for the quinone binding protein of photosystem II. This is the first report of a chloroplast sequence in a naturally occurring viral-like or plasmid DNA. The complete sequence of the S-1 chloroplast segment has been compared with homologous regions of six different chloroplast genes. The S-1 segment has diverged from the other genes both by length mutation and base substitution. Several of the length mutations are exact adjacent tandem duplications of 4 and 5 bp similar to "footprints" left after excision of transposable elements in maize nuclear DNA.

Sederoff, Ronald R.; Ronald, Pamela; Bedinger, Patricia; Rivin, Carol; Walbot, Virginia; Bland, Molly; Levings, C. S.

1986-01-01

362

Maize mitochondrial plasmid S-1 sequences share homology with chloroplast gene psbA.  

PubMed

The linear, 6397-base pair (bp), mitochondrial S-1 DNA molecule from maize contains a 420-bp segment that is homologous with the chloroplast gene (psbA) that codes for the quinone binding protein of photosystem II. This is the first report of a chloroplast sequence in a naturally occurring viral-like or plasmid DNA. The complete sequence of the S-1 chloroplast segment has been compared with homologous regions of six different chloroplast genes. The S-1 segment has diverged from the other genes both by length mutation and base substitution. Several of the length mutations are exact adjacent tandem duplications of 4 and 5 bp similar to "footprints" left after excision of transposable elements in maize nuclear DNA. PMID:3013725

Sederoff, R R; Ronald, P; Bedinger, P; Rivin, C; Walbot, V; Bland, M; Levings, C S

1986-06-01

363

Global radiation damage at 300 and 260 K with dose rates approaching 1 MGy s?1  

PubMed Central

Global radiation damage to 19 thaumatin crystals has been measured using dose rates from 3 to 680?kGy?s?1. At room temperature damage per unit dose appears to be roughly independent of dose rate, suggesting that the timescales for important damage processes are less than ?1?s. However, at T = 260?K approximately half of the global damage manifested at dose rates of ?10?kGy?s?1 can be outrun by collecting data at 680?kGy?s?1. Appreciable sample-to-sample variability in global radiation sensitivity at fixed dose rate is observed. This variability cannot be accounted for by errors in dose calculation, crystal slippage or the size of the data sets in the assay.

Warkentin, Matthew; Badeau, Ryan; Hopkins, Jesse B.; Mulichak, Anne M.; Keefe, Lisa J.; Thorne, Robert E.

2012-01-01

364

Visualizing S1P-directed cellular egress by intravital imaging.  

PubMed

Sphingosine-1-phosphate (S1P) is a bioactive lipid that provides cellular signals through plasma membrane G protein-coupled receptors. The S1P receptor signaling system has a fundamental and widespread function in licensing the exit and release of hematopoietically derived cells from various tissues into the circulation. Although the outlines of the mechanism have been established through genetic and pharmacologic perturbations, the temporal and spatial dynamics of the cellular events involved have been unclear. Recently, two-photon intravital imaging has been applied to living tissues to visualize the cellular movements and interactions that occur during egress processes. Here we discuss how some of these recent findings provide a clearer picture regarding S1P receptor signaling in modulating cell egress into the circulation. This article is part of a Special Issue entitled New Frontiers in Sphingolipid Biology. PMID:24090699

Giannouli, Christina C; Chandris, Panagiotis; Proia, Richard L

2014-05-01

365

On S-duality of 5d super Yang-Mills on S 1  

NASA Astrophysics Data System (ADS)

We study a duality of 5d maximally supersymmetric Yang-Mills on S 1, which exchanges the tower of Kaluza-Klein W-bosons and the tower of instantonic monopoles. This duality maps a non-simply-laced gauge theory to a simply-laced gauge theory twisted by an outer automorphism around S 1, and is closely related to the Langlands dual of affine Lie algebras. We also discuss how this S-duality is implemented in terms of 6d mathcal{N} = (2, 0) theory. This is straightforward except for the 6d theory of type SU(2 n + 1) with {mathbb{Z}_2} outer-automorphism twist, for which a few new properties are deduced. For example, this 6d theory, when reduced on an S 1 with {mathbb{Z}_2} twist, gives 5d USp(2 n) theory with nontrivial discrete 5d theta angle.

Tachikawa, Yuji

2011-11-01

366

Genetic Evidence for Involvement of Neuronally Expressed S1P1 Receptor in Nociceptor Sensitization and Inflammatory Pain  

PubMed Central

Sphingosine-1-phosphate (S1P) is a key regulator of immune response. Immune cells, epithelia and blood cells generate high levels of S1P in inflamed tissue. However, it is not known if S1P acts on the endings of nociceptive neurons, thereby contributing to the generation of inflammatory pain. We found that the S1P1 receptor for S1P is expressed in subpopulations of sensory neurons including nociceptors. Both S1P and agonists at the S1P1 receptor induced hypersensitivity to noxious thermal stimulation in vitro and in vivo. S1P-induced hypersensitivity was strongly attenuated in mice lacking TRPV1 channels. S1P and inflammation-induced hypersensitivity was significantly reduced in mice with a conditional nociceptor-specific deletion of the S1P1 receptor. Our data show that neuronally expressed S1P1 receptors play a significant role in regulating nociceptor function and that S1P/S1P1 signaling may be a key player in the onset of thermal hypersensitivity and hyperalgesia associated with inflammation.

Mair, Norbert; Benetti, Camilla; Andratsch, Manfred; Leitner, Michael G.; Constantin, Cristina E.; Camprubi-Robles, Maria; Quarta, Serena; Biasio, Wolfgang; Kuner, Rohini; Gibbins, Ian L.; Kress, Michaela; Haberberger, Rainer V.

2011-01-01

367

Autoantibodies to ?S1-Casein Are Induced by Breast-Feeding  

PubMed Central

Background The generation of antibodies is impaired in newborns due to an immature immune system and reduced exposure to pathogens due to maternally derived antibodies and placental functions. During nursing, the immune system of newborns is challenged with multiple milk-derived proteins. Amongst them, caseins are the main constituent. In particular, human ?S1-casein (CSN1S1) was recently shown to possess immunomodulatory properties. We were thus interested to determine if auto-antibodies to CSN1S1 are induced by breast-feeding and may be sustained into adulthood. Methods 62 sera of healthy adult individuals who were (n?=?37) or were not (n?=?25) breast-fed against human CSN1S1 were investigated by a new SD (surface display)-ELISA. For cross-checking, these sera were tested for anti Epstein-Barr virus (EBV) antibodies by a commercial ELISA. Results IgG-antibodies were predominantly detected in individuals who had been nursed. At a cut-off value of 0.4, the SD-ELISA identified individuals with a history of having been breast-fed with a sensitivity of 80% and a specificity of 92%. Under these conditions, 35 out of 37 sera from healthy donors, who where breast-fed, reacted positively but only 5 sera of the 25 donors who were not breast-fed. The duration of breast-feeding was of no consequence to the antibody reaction as some healthy donors were only short term breast-fed (5 days minimum until 6 weeks maximum), but exhibited significant serum reaction against human CSN1S1 nonetheless. Conclusion We postulate that human CSN1S1 is an autoantigen. The antigenicity is orally determined, caused by breast-feeding, and sustained into adulthood.

Petermann, Klaudia; Vordenbaumen, Stefan; Maas, Ruth; Braukmann, Achim; Bleck, Ellen; Saenger, Thorsten; Schneider, Matthias; Jose, Joachim

2012-01-01

368

Dose-finding study on adjuvant chemotherapy with S-1 plus oxaliplatin for gastric cancer  

PubMed Central

Gastric cancer (GC) is the fourth most common type of cancer, accounting for an estimated one million new cases annually worldwide. Locally advanced GC often recurs, even following curative surgical resection. Therefore, there is a need for an effective adjuvant chemotherapy regimen. The aim of this trial was to investigate the maximum tolerated dose (MTD) of S-1 when administered in combination with oxaliplatin in postoperative GC patients. Oxaliplatin was administered at a fixed dose of 130 mg/m2 on day 1. S-1 was administered from day 1 to 14 of a 3-week cycle and escalated by 10 mg/m2/day from 60 to 80 mg/m2/day. A total of 15 patients were enrolled in this study. No dose-limiting toxicities (DLTs) occurred at level 1 (S-1, 60 mg/m2; n=3). One case of DLT (grade 3 vomiting) occurred at level 2 (S-1, 70 mg/m2; n= 6), whereas 2 cases of grade 3 vomiting were observed at level 3 (S-1, 80 mg/m2; n=6). Based on these results, the MTD of S-1 was initially determined to be 70 mg/m2. Furthermore, we observed that cytochrome P450 2A6 (CYP2A6) 41349640C>G was associated with severe neutropenia (C/C vs. C/G vs. G/G = 0 vs. 33.33 vs. 100%; P=0.03297, Fisher’s exact test) during the entire course of the treatment.

YANG, LIN; YANG, YI; QIN, QIONG; ZHOU, AIPING; ZHAO, JIANJUN; WANG, JINWAN; SHU, CHANG; YUAN, XINGHUA; HU, SONGNIAN

2014-01-01

369

S1 of distinct IBV population expressed from recombinant adenovirus confers protection against challenge.  

PubMed

Protective properties of three distinct infectious bronchitis virus (IBV) Ark Delmarva poultry industry (ArkDPI) S1 proteins encoded from replication-defective recombinant adenovirus vectors were investigated. Using a suboptimal dose of each recombinant virus, we demonstrated that IBV S1 amino acid sequences showing > or = 95.8% amino acid identity to the S1 of the challenge strain differed in their ability at conferring protection. Indeed, the S1 sequence of the IBV population previously designated C4 (AdIBVS1.C4), which protected the most poorly, differs from the S1 sequence of population C2 (AdIBVS1.C2), which provided the highest protection, only at amino acid position 56. The fact that a change in one amino acid in this region significantly altered the induction of a protective immune response against this protein provides evidence that the first portion of S1 displays relevant immunoprotective epitopes. Use of an optimal dose of AdIBVS1.C2 effectively protected chickens from clinical signs and significantly reduced viral load after IBV Ark virulent challenge. Moreover, increased numbers of both IgA and IgG IBV-specific antibody secreting lymphocytes were detected in the spleen after challenge. The increased response detected for both IgA and IgG lymphocytes after challenge might be explained by vaccine-induced B memory cells. The fact that a single vaccination with Ad/IBVS1.C2 provides protection against IBV challenge is promising, because Ad-vectored vaccines can be mass delivered by in ovo inoculation using automated in ovo injectors. PMID:25055623

Toro, H; Zhang, J F; Gallardo, R A; van Santen, V L; van Ginkel, F W; Joiner, K S; Breedlove, C

2014-06-01

370

ROLE OF S-1-P RECEPTORS AND HUMAN VASCULAR SMOOTH MUSCLE CELL MIGRATION IN DIABETES AND METABOLIC SYNDROME  

PubMed Central

Background Sphingosine-1-phosphate (S-1-P) is a bioactive sphingolipid released from activated platelets that stimulates migration of vascular smooth muscle cells (VSMC) in vitro. S-1-P is associated with oxidized low-density lipoprotein (oxLDL) and is important in vessel remodeling. S-1-P will activate multiple G protein-coupled receptors (S-1-PR 1 to 5) which can regulate multiple cellular functions, including cell migration. The aim of this study is to examine the role of S-1-PR signaling during smooth muscle cell migration in response to S-1-P. Methods Human VSMCs were cultured in vitro. Expression of S-1-PR 1 to 5 was determined in conditions mirroring diabetes (40 mM glucose) and metabolic syndrome (25 mM glucose with 20 µM linoleic acid and 20 µM oleic acid). Linear wound and Boyden microchemotaxis assays of migration were performed in the presence of S-1-P with and without siRNA against S-1-PR 1 to 5. Assays were performed for activation of ERK1/2, p38MAPK and JNK. Results Human VSMCs express S-1-PR1, S-1-PR2 and S-1-PR3. There was no significant expression of S-1-PR4 and S-1-PR5. The expression of S-1-PR1 and S-1-PR3 is enhanced under high glucose conditions and metabolic syndrome conditions. Migration of VSMC in response to S-1-P is enhanced 2 fold by diabetes and 4 fold by metabolic syndrome. In diabetes, S-1-PR1 expression is enhanced, while S-1-PR2 and S-1-PR3 expression are both maintained. In metabolic syndrome, S-1-PR1 and 3 expression are enhanced and that of S-1-PR2 is reduced. siRNA to S-1-PR1 results in a 2-fold reduction in S-1-P-mediated cell migration under all conditions. siRNA to S-1-PR2 enhanced cell migration only under normal conditions, while siRNA S-1-PR3 decreased migration in metabolic syndrome only. Down regulation of S-1-PR1 reduced ERK1/2 activation in response to S-1-P, while that of S-1-PR2 had no effect under normal conditions. In diabetes, down regulation of S-1-PR1 reduced activation of all three MAPKs. In metabolic syndrome, down regulation of S-1-PR1 and S-1-PR3 reduced activation of all three MAPKs. Conclusion S-1-PR 1, 2 and 3 regulate human VSMC migration and their expression level and function are modulated by conditions simulating diabetes and metabolic syndrome.

Duru, Enrico A.; Fu, Yuyang; Davies, Mark G.

2011-01-01

371

Sequence selective double strand DNA cleavage by peptide nucleic acid (PNA) targeting using nuclease S1.  

PubMed Central

A novel method for sequence specific double strand DNA cleavage using PNA (peptide nucleic acid) targeting is described. Nuclease S1 digestion of double stranded DNA gives rise to double strand cleavage at an occupied PNA strand displacement binding site, and under optimized conditions complete cleavage can be obtained. The efficiency of this cleavage is more than 10 fold enhanced when a tandem PNA site is targeted, and additionally enhanced if this site is in trans rather than in cis orientation. Thus in effect, the PNA targeting makes the single strand specific nuclease S1 behave like a pseudo restriction endonuclease. Images

Demidov, V; Frank-Kamenetskii, M D; Egholm, M; Buchardt, O; Nielsen, P E

1993-01-01

372

Optimization of a Potent, Orally Active S1P1 Agonist Containing a Quinolinone Core  

PubMed Central

The optimization of a series of S1P1 agonists with limited activity against S1P3 is reported. A polar headgroup was used to improve the physicochemical and pharmacokinetic parameters of lead quinolinone 6. When dosed orally at 1 and 3 mg/kg, the azahydroxymethyl analogue 22 achieved statistically significant lowering of circulating blood lymphocytes 24 h postdose. In rats, a dose-proportional increase in exposure was measured when 22 was dosed orally at 2 and 100 mg/kg.

2011-01-01

373

Phase II study of S-1 monotherapy in paclitaxel- and cisplatin-refractory gastric cancer  

Microsoft Academic Search

Purpose  S-1 is a fourth-generation oral fluoropyrimidine that was developed to mimic the effects achieved with protracted continuous\\u000a infusion of 5-fluorouracil (5-FU). This phase II study evaluated the efficacy and safety of S-1 salvage chemotherapy in patients\\u000a with paclitaxel- and cisplatin-refractory gastric cancer. The primary end point was progression-free survival; secondary end\\u000a points were overall survival, safety, and clinical benefit.\\u000a \\u000a \\u000a \\u000a Methods  Patients

Sung-Ji Lee; Sang-Hee Cho; Ju-Young Yoon; Jun-Eul Hwang; Woo-Kyun Bae; Hyun-Jeong Shim; Ik-Joo Chung

2009-01-01

374

Constrainingquasar and intergalactic medium properties through bubble detection in redshifted 21-cm maps  

NASA Astrophysics Data System (ADS)

The infrared detection of a z > 7 quasar has opened up a window to directly probe the intergalactic medium (IGM) during the epoch of reionization. It is anticipated that future observations will yield more quasars extending to higher redshifts. In this paper, we theoretically consider the possibility of detecting the ionized bubble around a z = 8 quasar using targeted redshifted 21-cm observations with the GMRT. The apparent shape and size of the ionized bubble, as seen by a distant observer, depends on the parameters ? phs /C, xH i /c and ?Q, where ? phs and ?Q are, respectively, the ionizing photon emission rate and age of the quasar, and xH i and C are, respectively, the neutral fraction and clumping factor of the IGM. The 21-cm detection of an ionized bubble, thus, holds the promise of allowing us to probe the quasar and IGM properties at z = 8. In this work we have analytically calculated the apparent shape and size of a quasar's ionized bubble assuming a uniform IGM and ignoring other ionizing sources besides the quasar, and used this as a template for matched-filter bubble search with the GMRT visibility data. We have assumed that ? phs is known from the observed infrared spectrum, and C = 30 from theoretical considerations, which gives us the two free parameters xH i and ?Q for bubble detection. Considering 1000'h of observation, we find that there is a reasonably large region of parameter space bounded within (xH i , (?Q/107 yr ))=(1.0, 0.5) and (0.2, 7.0) where a 3? detection is possible if (? phs /1057 s-1)=3. The available region increases if ? phs is larger, whereas we need xH i ?0.4 and (?Q/107 yr )?2.0 if (? phs /1057 s-1)=1.3. Considering parameter estimation, we find that in many cases it will be possible to quite accurately constrain ?Q and place a lower limit on xH i with 1000'h of observation, particularly if the bubble is in the early stage of growth and we have a very luminous quasar or a high neutral fraction. Deeper follow-up observations (4000 and 9000'h) can be used to further tighten the constraints on ?Q and xH i . We find that the estimated xH i is affected by uncertainty in the assumed value of C. The quasar's age ?Q however is robust and is unaffected by the uncertainty in C. The presence of other ionizing sources and inhomogeneities in the IGM distort the shape and size of the quasar's ionized bubble. This is a potential impediment for bubble detection and parameter estimation. We have used the seminumerical technique to simulate the apparent shape and size of quasar ionized bubbles incorporating these effects. If we consider a 9000'h of observation with the GMRT, we find that the estimated parameters ?Q and xH i are expected to be within the statistical uncertainties.

Majumdar, Suman; Bharadwaj, Somnath; Choudhury, T. Roy

2012-11-01

375

Accurate measurement of the H I column density from H I 21 cm absorption-emission spectroscopy  

NASA Astrophysics Data System (ADS)

We present a detailed study of an estimator of the H I column density, based on a combination of H I 21 cm absorption and H I 21cm emission spectroscopy. This `isothermal' estimate is given by NHI, ISO = 1.823 × 1018 ? [?tot × TB / [ 1 - e-?tot]dV, where ?tot is the total H I 21cm optical depth along the sightline and TB is the measured brightness temperature. We have used a Monte Carlo simulation to quantify the accuracy of the isothermal estimate by comparing the derived NHI, ISO with the true H I column density NHI. The simulation was carried out for a wide range of sightlines, including gas in different temperature phases and random locations along the path. We find that the results are statistically insensitive to the assumed gas temperature distribution and the positions of different phases along the line of sight. The median value of the ratio of the true H I column density to the isothermal estimate, NHI/NHI, ISO, is within a factor of 2 of unity while the 68.2 per cent confidence intervals are within a factor of ?3 of unity, out to high H I column densities, ?5 × 1023 cm-2 per 1 km s-1 channel, and high total optical depths, ?1000. The isothermal estimator thus provides a significantly better measure of the H I column density than other methods, within a factor of a few of the true value even at the highest columns, and should allow us to directly probe the existence of high H I column density gas in the Milky Way.

Chengalur, Jayaram N.; Kanekar, Nissim; Roy, Nirupam

2013-07-01

376

Crossed-Beam Dynamics, Low-Temperature Kinetics, and Theoretical Studies of the Reaction S(1D) + C2H4  

NASA Astrophysics Data System (ADS)

The reaction between sulfur atoms in the first electronically excited state, S(1D), and ethene (C2H4) has been investigated in a complementary fashion in (a) crossed-beam dynamic experiments with mass spectrometric detection and time-of-flight (TOF) analysis at two collision energies (37.0 and 45.0 kJ mol-1), (b) low temperature kinetics experiments ranging from 298 K down to 23 K, and (c) electronic structure calculations of stationary points and product energetics on the C2H4S singlet and triplet potential energy surfaces. The rate coefficients for total loss of S(1D) are found to be very large (ca. 4 × 10-10 cm3 molecule-1 s-1) down to very low temperatures indicating that the overall reaction is barrierless. From laboratory angular and TOF distributions at different product masses, three competing reaction channels leading to H + CH2CHS (thiovinoxy), H2 + CH2CS (thioketene), and CH3 + HCS (thioformyl) have been unambiguously identified and their dynamics characterized. Product branching ratios have also been estimated. Interpretation of the experimental results on the reaction kinetics and dynamics is assisted by high-level theoretical calculations on the C2H4S singlet potential energy surface. RRKM (Rice-Ramsperger-Kassel-Marcus) estimates of the product branching ratios using the newly developed singlet potential energy surface have also been performed and compared with the experimental determinations.

Leonori, Francesca; Petrucci, Raffaele; Balucani, Nadia; Casavecchia, Piergiorgio; Rosi, Marzio; Skouteris, Dimitris; Berteloite, Coralie; Le Picard, Sébastien D.; Canosa, André; Sims, Ian R.

2009-09-01

377

Velocity Relaxation of S(1D) by Rare Gases Measured by Doppler Spectroscopy. (Reannouncement with New Availability Information).  

National Technical Information Service (NTIS)

Velocity relaxation of S(1D) by He, Ar, and Xe has been monitored by measuring the Doppler profile of the S(1D) for variable collision partner pressures at a fixed time delay following creation of S(1D) by pulsed laser photolysis of OCS at 222 nm. The nas...

G. Nan P. L. Houston

1992-01-01

378

Ultrafast excited state dynamics of S2 and S1 states of triphenylmethane dyes.  

PubMed

Excited state dynamics of S2 and S1 states for a series of TPM dyes, pyrogallol red (PGR), bromopyrogallol red (Br-PGR) and aurin tricarboxylic acid (ATC), have been monitored by using ultrafast transient absorption and fluorescence up-conversion techniques. Optical absorption studies indicate that all the TPM dyes exist as keto-enol tautomers depending upon the pH of the solution. Interestingly, all the TPM dyes give S2 emission (major emitting state) in addition to weak S1 emission. S2 emission lifetimes as fast as ?150-300 fs and S1 emission lifetimes of 2-5 ns were observed depending upon the molecular structure of the dyes. Femtosecond transient absorption studies suggest the presence of an ultrafast non-radiative decay channel from the S2 state in addition to S2 luminescence. The vibrational relaxation time from hot S1 state is found to be 2-6 ps. The heavy atom effect has been observed in ultrafast relaxation dynamics of Br-PGR. PMID:25003589

Singhal, Pallavi; Ghosh, Hirendra N

2014-07-16

379

Function of the Conserved S1 and KH Domains in Polynucleotide Phosphorylase  

PubMed Central

We have examined the roles of the conserved S1 and KH RNA binding motifs in the widely dispersed prokaryotic exoribonuclease polynucleotide phosphorylase (PNPase). These domains can be released from the enzyme by mild proteolysis or by truncation of the gene. Using purified recombinant enzymes, we have assessed the effects of specific deletions on RNA binding, on activity against a synthetic substrate under multiple-turnover conditions, and on the ability of truncated forms of PNPase to form a minimal RNA degradosome with RNase E and RhlB. Deletion of the S1 domain reduces the apparent activity of the enzyme by almost 70-fold under low-ionic-strength conditions and limits the enzyme to digest a single substrate molecule. Activity and product release are substantially regained at higher ionic strengths. This deletion also reduces the affinity of the enzyme for RNA, without affecting the enzyme's ability to bind to RNase E. Deletion of the KH domain produces similar, but less severe, effects, while deletion of both the S1 and KH domains accentuates the loss of activity, product release, and RNA binding but has no effect on binding to RNase E. We propose that the S1 domain, possibly arrayed with the KH domain, forms an RNA binding surface that facilitates substrate recognition and thus indirectly potentiates product release. The present data as well as prior observations can be rationalized by a two-step model for substrate binding.

Stickney, Leigh M.; Hankins, Janet S.; Miao, Xin; Mackie, George A.

2005-01-01

380

Function of the conserved S1 and KH domains in polynucleotide phosphorylase.  

PubMed

We have examined the roles of the conserved S1 and KH RNA binding motifs in the widely dispersed prokaryotic exoribonuclease polynucleotide phosphorylase (PNPase). These domains can be released from the enzyme by mild proteolysis or by truncation of the gene. Using purified recombinant enzymes, we have assessed the effects of specific deletions on RNA binding, on activity against a synthetic substrate under multiple-turnover conditions, and on the ability of truncated forms of PNPase to form a minimal RNA degradosome with RNase E and RhlB. Deletion of the S1 domain reduces the apparent activity of the enzyme by almost 70-fold under low-ionic-strength conditions and limits the enzyme to digest a single substrate molecule. Activity and product release are substantially regained at higher ionic strengths. This deletion also reduces the affinity of the enzyme for RNA, without affecting the enzyme's ability to bind to RNase E. Deletion of the KH domain produces similar, but less severe, effects, while deletion of both the S1 and KH domains accentuates the loss of activity, product release, and RNA binding but has no effect on binding to RNase E. We propose that the S1 domain, possibly arrayed with the KH domain, forms an RNA binding surface that facilitates substrate recognition and thus indirectly potentiates product release. The present data as well as prior observations can be rationalized by a two-step model for substrate binding. PMID:16237005

Stickney, Leigh M; Hankins, Janet S; Miao, Xin; Mackie, George A

2005-11-01

381

Function of the Conserved S1 and KH Domains in Polynucleotide Phosphorylase  

Microsoft Academic Search

We have examined the roles of the conserved S1 and KH RNA binding motifs in the widely dispersed prokaryotic exoribonuclease polynucleotide phosphorylase (PNPase). These domains can be released from the enzyme by mild proteolysis or by truncation of the gene. Using purified recombinant enzymes, we have assessed the effects of specific deletions on RNA binding, on activity against a synthetic

Leigh M. Stickney; Janet S. Hankins; Xin Miao; George A. Mackie

2005-01-01

382

Raman scattering in a Heisenberg S = 1\\/2 antiferromagnet on the anisotropic triangular lattice  

Microsoft Academic Search

We investigate two-magnon Raman scattering from the S = 1\\/2 Heisenberg antiferromagnet on the triangular lattice (THAF), considering both isotropic and anisotropic exchange interactions. We find that the Raman intensity for the isotropic THAF is insensitive to the scattering geometry, while both the line profile and the intensity of the Raman response for the anisotropic THAF shows a strong dependence

Natalia Perkins; Wolfram Brenig

2009-01-01

383

Characterization of Samples from Old Solvent Tanks S1 through S22.  

National Technical Information Service (NTIS)

The Old Radioactive Waste Burial Ground (ORWBG, 643-E) contains 22 old solvent tanks (S1 - S22) which were used to receive and store spent PUREX solvent from F- and H-Canyons. The tanks are cylindrical, carbon-steel, single-wall vessels buried at varying ...

J. D. Leyba

1999-01-01

384

Engagement of S1P1-degradative mechanisms leads to vascular leak in mice  

PubMed Central

GPCR inhibitors are highly prevalent in modern therapeutics. However, interference with complex GPCR regulatory mechanisms leads to both therapeutic efficacy and adverse effects. Recently, the sphingosine-1-phosphate (S1P) receptor inhibitor FTY720 (also known as Fingolimod), which induces lymphopenia and prevents neuroinflammation, was adopted as a disease-modifying therapeutic in multiple sclerosis. Although highly efficacious, dose-dependent increases in adverse events have tempered its utility. We show here that FTY720P induces phosphorylation of the C-terminal domain of S1P receptor 1 (S1P1) at multiple sites, resulting in GPCR internalization, polyubiquitinylation, and degradation. We also identified the ubiquitin E3 ligase WWP2 in the GPCR complex and demonstrated its requirement in FTY720-induced receptor degradation. GPCR degradation was not essential for the induction of lymphopenia, but was critical for pulmonary vascular leak in vivo. Prevention of receptor phosphorylation, internalization, and degradation inhibited vascular leak, which suggests that discrete mechanisms of S1P receptor regulation are responsible for the efficacy and adverse events associated with this class of therapeutics.

Oo, Myat Lin; Chang, Sung-Hee; Thangada, Shobha; Wu, Ming-Tao; Rezaul, Karim; Blaho, Victoria; Hwang, Sun-Il; Han, David K.; Hla, Timothy

2011-01-01

385

Long Term Survival on S-1 Monotherapy in a Patient with Recurrent Stage IV Pancreatic Cancer  

Microsoft Academic Search

Context Pancreatic cancer is the third most common gastrointestinal malignancy in the United States. Due to difficulty in diagnosis, 40% of patients are stage IV by the time of diagnosis and median survival is only four to six months. Current therapy for advanced pancreatic cancer focuses largely on gemcitabine. However, a relatively new drug, S-1, is showing promising results. Phase

Susan Alsamarai; Chris Zergebel; Joshua Zhang; Taro Furuie; Peter D Urrea; Muhammad Wasif Saif

386

Comparison of the pharmacokinetics and pharmacodynamics of S-1 between Caucasian and East Asian patients.  

PubMed

S-1 is an oral fluoropyrimidine anti-neoplastic agent that is converted by CYP2A6 to 5-fluorouracil (5FU). We prospectively studied the pharmacokinetics and pharmacodynamics of S-1 in two groups of East Asian and Caucasian patients with solid malignancy refractory to standard chemotherapy, or for which 5FU was indicated, to elucidate differences in relation to CYP2A6 genotype and phenotype. S-1 was given orally at 30 mg/m(2) b.i.d. for 14 days every 21 days. Dose normalized AUC(0-48 h) for tegafur (P = 0.05) and gimeracil (P = 0.036) were higher in East Asians; conversely, AUC(0-48 h) of fluoro-?-alanine was higher in Caucasians (P = 0.044). Exposure to 5FU was similar in both groups (P = 0.967). Mean cotinine:nicotine ratio was 54% higher in the Caucasian group (P = 0.03), and correlated with oral clearance of tegafur (r = 0.59; P = 0.002). Grade 3/4 gastrointestinal toxicities were more common in Caucasians than Asians (21%vs 0%). Treatment with S-1 yields no significant difference in 5FU exposure between Caucasians and East Asians. PMID:21143703

Chuah, Benjamin; Goh, Boon-Cher; Lee, Soo-Chin; Soong, Richie; Lau, Fayce; Mulay, Marilyn; Dinolfo, Melissa; Lim, Siew-Eng; Soo, Ross; Furuie, Taro; Saito, Kaku; Zergebel, Christopher; Rosen, Lee S

2011-02-01

387

Equine alpha S1-casein: characterization of alternative splicing isoforms and determination of phosphorylation levels.  

PubMed

alpha(S1)-Casein was isolated from Haflinger mare's milk by hydrophobic interaction chromatography and displayed great micro-heterogeneity by 2-dimensional electrophoresis, probably because of a variable degree of phosphorylation and alternative splicing events. The aim of the present work was to investigate the complexity of the mare's alpha(S1)-casein. The different isoforms present in milk were submitted to a double treatment of dephosphorylation, first by using alkaline phosphatase and then acid phosphatase to achieve complete dephosphorylation. The apoforms were then analyzed by electrospray ionization mass spectrometry. The results revealed the existence of a full-length protein and 7 variants resulting from posttranscriptional modifications; that is, exon skipping involving exon 7, exon 14, or both and use of a cryptic splice site encoding a glutamine residue. The determination of the different phosphorylation degrees of the native isoforms of alpha(S1)-casein was finally achieved by electrospray ionization mass spectrometry analysis after fractionation of the isoforms by ion-exchange chromatography. Thus, 36 different variants of equine alpha(S1)-casein were identified with several phosphate groups ranging from 2 to 6 or 8 depending on whether exon 7 was skipped. PMID:19620641

Matéos, A; Miclo, L; Mollé, D; Dary, A; Girardet, J-M; Gaillard, J-L

2009-08-01

388

Application of S1BYL2 to the AGARD WG18 Compressor Test Cases.  

National Technical Information Service (NTIS)

S1BYL2 is an inviscid viscous blade to blade method for calculating the detailed aerodynamics and overall performance of compressor blades. It may be applied either on its own to predict the flow for individual blade sections, such as the mid span of a li...

W. J. Calvert

1991-01-01

389

Alpha s1-casein, milk composition and coagulation properties of goat milk  

Microsoft Academic Search

Amounts of alphas1-casein (?s1-CN), protein, fat, SNF and total solids were measured in 125 goat milk samples. Coagulation time, coagulation rate and curd firmness were measured in 75 goat milk samples by dynamic mechanical analysis using a Bohlin VOR Rheometer. After adjustments were made for month, time of milk collection and animal age, it was confirmed that goat milk with

S. Clark; J. W. Sherbon

2000-01-01

390

Protein S1 counteracts the inhibitory effect of the extended Shine-Dalgarno sequence on translation.  

PubMed Central

There are two major components of Escherichia coli ribosomes directly involved in selection and binding of mRNA during initiation of protein synthesis-the highly conserved 3' end of 16S rRNA (aSD) complementary to the Shine-Dalgarno (SD) domain of mRNA, and the ribosomal protein S1. A contribution of the SD-aSD and S1-mRNA interactions to translation yield in vivo has been evaluated in a genetic system developed to compare efficiencies of various ribosome-binding sites (RBS) in driving beta-galactosidase synthesis from the single-copy (chromosomal) lacZ gene. The in vivo experiments have been supplemented by in vitro toeprinting and gel-mobility shift assays. A shortening of a potential SD-aSD duplex from 10 to 8 and to 6 bp increased the beta-galactosidase yield (four- and sixfold, respectively) suggesting that an extended SD-aSD duplex adversely affects translation, most likely due to its redundant stability causing ribosome stalling at the initiation step. Translation yields were significantly increased upon insertion of the A/U-rich S1 binding targets upstream of the SD region, but the longest SD remained relatively less efficient. In contrast to complete 30S ribosomes, the S1-depleted 30S particles have been able to form an extended SD-aSD duplex, but not the true ternary initiation complex. Taken together, the in vivo and in vitro data allow us to conclude that S1 plays two roles in translation initiation: It forms an essential part of the mRNA-binding track even when mRNA bears a long SD sequence, and through the binding to the 5' untranslated region, it can ensure a substantial enhancing effect on translation.

Komarova, Anastassia V; Tchufistova, Ludmila S; Supina, Elena V; Boni, Irina V

2002-01-01

391

Relapse-associated microRNA in gastric cancer patients after S-1 adjuvant chemotherapy.  

PubMed

S-1 has been recommended as adjuvant chemotherapy in patients after curative surgery for gastric cancer. However, some patients suffer recurrence even after S-1 adjuvant chemotherapy. The present study was conducted to find a predictive marker of the efficacy of S-1 adjuvant chemotherapy. We examined the microRNA (miRNA) expression of 35 patients who underwent S-1 adjuvant chemotherapy after curative surgery (R0) for pathological stage II or III gastric cancer. miRNAs were extracted from formalin-fixed, paraffin-embedded specimens for analysis and miRNA expression was examined using miRNA oligo chips. Fifteen patients relapsed and 20 did not over 5 years. Five miRNAs (miR-92b, 422a, 4732-5p, 4758-3p and 221) were highly expressed according to the tumor/normal (T/N) ratio in the patients who relapsed but not in those who did not relapse (P-value <0.05) by microarray analysis. If tumors showed high expression of 4 miRNAs (miR-92b, 422a, 4732-5p and 4758-3p) their positive predictive value of relapse was 93.8% and negative predictive value was 92.3%. In this case, their disease-free survival rate and overall survival rate were very poor. Our findings indicate that miR-92b, miR?422a, miR-4732-5p and miR-4758-3p are closely associated with relapse following S-1 adjuvant chemotherapy in gastric cancer. PMID:24317477

Omura, Tetsuya; Shimada, Yutaka; Nagata, Takuya; Okumura, Tomoyuki; Fukuoka, Junya; Yamagishi, Fuminori; Tajika, Sadakatsu; Nakajima, Sanae; Kawabe, Atsushi; Tsukada, Kazuhiro

2014-02-01

392

Characterization of a periplasmic S1-like nuclease coded by the Mesorhizobium loti symbiosis island  

SciTech Connect

DNA sequences encoding hypothetical proteins homologous to S1 nuclease from Aspergillus oryzae are found in many organisms including fungi, plants, pathogenic bacteria, and eukaryotic parasites. One of these is the M1 nuclease of Mesorhizobium loti which we demonstrate herein to be an enzymatically active, soluble, and stable S1 homolog that lacks the extensive mannosyl-glycosylation found in eukaryotic S1 nuclease homologs. We have expressed the cloned M1 protein in M. loti and purified recombinant native M1 to near homogeneity and have also isolated a homogeneous M1 carboxy-terminal hexahistidine tag fusion protein. Mass spectrometry and N-terminal Edman degradation sequencing confirmed the protein identity. The enzymatic properties of the purified M1 nuclease are similar to those of S1. At acidic pH M1 is 25 times more active on single-stranded DNA than on double-stranded DNA and 3 times more active on single-stranded DNA than on single-stranded RNA. At neutral pH the RNase activity of M1 exceeds the DNase activity. M1 nicks supercoiled RF-I plasmid DNA and rapidly cuts the phosphodiester bond across from the nick in the resultant relaxed RF-II plasmid DNA. Therefore, M1 represents an active bacterial S1 homolog in spite of great sequence divergence. The biochemical characterization of M1 nuclease supports our sequence alignment that reveals the minimal 21 amino acid residues that are necessarily conserved for the structure and functions of this enzyme family. The ability of M1 to degrade RNA at neutral pH implies previously unappreciated roles of these nucleases in biological systems.

Pimkin, Maxim [Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111 (United States); Miller, C. Glenn [Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111 (United States); Blakesley, Lauryn [Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111 (United States); Oleykowski, Catherine A. [Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111 (United States); Kodali, Nagendra S. [Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111 (United States); Yeung, Anthony T. [Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111 (United States)]. E-mail: AT_Yeung@fccc.edu

2006-04-28

393

Evidence-based support for S1 transpedicular screw entry point modification  

PubMed Central

Background In the literature, ‘below and lateral to the superior S1 facet’ is defined as the basic technique for screw introduction. Until a recently published modification, no analysis for alternative starting point has been proposed nor evaluated, although some surgeons claim to use some modifications. In this study, we analyse the data from anatomical and radiological studies for optimal starting point in transpedicular S1 screw placement. Methods A Medline search for key word combination: sacrum, anatomy, pedicle, screws and bone density resulted in 26 publications relevant to the topic. After a review of literature, two articles were chosen, as those including the appropriate set of data. The data retrieved from the articles is used for the analysis. The spatial relation of S1 facet, pedicles and vertebral body with cortical thickness and bone density in normal, osteopenic and osteoporotic sacrum is analysed. Results Presented data advocates for more medial placement of the screws due to higher bone density and lower bone loss in osteoporosis. Medial shift of the starting point does not increase the risk of spinal canal perforation. Osteoarthritic changes within the facet can augment the posterior supporting point for screw. The facet angular orientation is similar to convergent screw trajectory. Conclusions Modified technique for S1 screw placement takes advantage of latest anatomical and clinical data. In our opinion, technique modification improves the reproducibility and may increase stability and the screws within the posterior cortex of the S1 vertebra. Further biomechanical and clinical study should be performed to prove its superiority to classical technique.

2014-01-01

394

Search for the flavor-changing neutral current decay B0s--> mu(+) mu(-) in pp Collisions at sqrt[s] = 1.96 TeV with the D0 detector.  

PubMed

We present the results of a search for the flavor-changing neutral current decay B(0)(s)--> mu(+) mu(-) using a data set with integrated luminosity of 240 pb(-1) of pp collisions at sqrt[s] = 1.96 TeV collected with the D0 detector in run II of the Fermilab Tevatron collider. We find the upper limit on the branching fraction to be B(B(0)(s)--> mu(+) mu(-)) < or= 5.0 x 10(-7) at the 95% C.L. assuming no contributions from the decay B(0)(d)--> mu(+) mu(-) in the signal region. This limit is the most stringent upper bound on the branching fraction B(0)(s)--> mu(+) mu(-) to date. PMID:15783803

Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Agelou, M; Agram, J-L; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Anderson, S; Andrieu, B; Arnoud, Y; Askew, A; Asman, B; Atramentov, O; Autermann, C; Avila, C; Badaud, F; Baden, A; Baldin, B; Balm, P W; Banerjee, S; Barberis, E; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Beauceron, S; Begel, M; Bellavance, A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Blumenschein, U; Boehnlein, A; Boeriu, O; Bolton, T A; Borcherding, F; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burnett, T H; Busato, E; Butler, J M; Bystricky, J; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chapin, D; Charles, F; Cheu, E; Chevalier, L; Cho, D K; Choi, S; Christiansen, T; Christofek, L; Claes, D; Clément, B; Clément, C; Coadou, Y; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Coss, J; Cothenet, A; Cousinou, M-C; Crépé-Renaudin, S; Cristetiu, M; Cummings, M A C; Cutts, D; da Motta, H; Davies, B; Davies, G; Davis, G A; De, K; de Jong, P; de Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Dean, S; Déliot, F; Delsart, P A; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doidge, M; Dong, H; Doulas, S; Duflot, L; Dugad, S R; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Eltzroth, J T; Elvira, V D; Eno, S; Ermolov, P; Eroshin, O V; Estrada, J; Evans, D; Evans, H; Evdokimov, A; Evdokimov, V N; Fast, J; Fatakia, S N; Feligioni, L; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Freeman, W; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Garcia, C; Garcia-Bellido, A; Gardner, J; Gavrilov, V; Gay, P; Gelé, D; Gelhaus, R; Genser, K; Gerber, C E; Gershtein, Y; Ginther, G; Golling, T; Gómez, B; Gounder, K; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Gris, Ph; Grivaz, J-F; Groer, L; Grünendahl, S; Grünewald, M W; Gurzhiev, S N; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Hagopian, S; Hall, I; Hall, R E; Han, C; Han, L; Hanagaki, K; Harder, K; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hong, S J; Hooper, R; Houben, P; Hu, Y; Huang, J; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jain, V; Jakobs, K; Jenkins, A; Jesik, R; Johns, K; Johnson, M; Jonckheere, A; Jonsson, P; Jöstlein, H; Juste, A; Kado, M M; Käfer, D; Kahl, W; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J; Karmanov, D; Kasper, J; Kau, D; Kehoe, R; Kermiche, S; Kesisoglou, S; Khanov, A; Kharchilava, A; Kharzheev, Y M; Kim, K H; Klima, B; Klute, M; Kohli, J M; Kopal, M; Korablev, V M; Kotcher, J; Kothari, B; Koubarovsky, A; Kozelov, A V; Kozminski, J; Krzywdzinski, S; Kuleshov, S; Kulik, Y; Kunori, S; Kupco, A; Kurca, T; Lager, S; Lahrichi, N; Landsberg, G; Lazoflores, J; Le Bihan, A-C; Lebrun, P; Lee, S W; Lee, W M; Leflat, A; Lehner, F; Leonidopoulos, C; Lewis, P; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linn, S L; Linnemann, J; Lipaev, V V; Lipton, R; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Lubatti, H J; Lueking, L; Lynker, M; Lyon, A L; Maciel, A K A; Madaras, R J; Mättig, P; Magerkurth, A; Magnan, A-M; Makovec, N; Mal, P K; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martens, M; Mattingly, S E K; Mayorov, A A; McCarthy, R; McCroskey, R; Meder, D; Melanson, H L; Melnitchouk, A; Merkin, M; Merritt, K W; Meyer, A; Miettinen, H; Mihalcea, D; Mitrevski, J; Mokhov, N; Molina, J; Mondal, N K; Montgomery, H E; Moore, R W; Muanza, G S; Mulders, M; Mutaf, Y D; Nagy, E; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Nelson, S; Neustroev, P; Noeding, C; Nomerotski, A; Novaes, S F; Nunnemann, T; Nurse, E; O'dell, V; O'neil, D C; Oguri, V; Oliveira, N; Oshima, N; Otero Y Garzón, G J; Padley, P; Parashar, N; Park, J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Perea, P M; Perez, E; Peters, O; Pétroff, P; Petteni, M; Phaf, L; Piegaia, R; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pope, B G; Prado da Silva, W L; Prosper, H B; Protopopescu, S; Przybycien, M B; Qian, J; Quadt, A; Quinn, B; Rani, K J; Rapidis, P A; Ratoff, P N; Reay, N W; Reucroft, S; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Royon, C; Rubinov, P; Ruchti, R; Sajot, G; Sánchez-Hernández, A; Sanders, M P

2005-02-25

395

Modeling the behavior of Cm and Am during separation by complexing extraction chromatography  

SciTech Connect

Certain heavy rare earths (REE), Cm, and Am are separated by complexing extraction chromatography using solutions of DTPA and DTPA-citric acid as eluents. The separation coefficients of REE from Cm and Am are calculated. Tracers are proposed for the Cm and Am separations. These are Tm for Cm elution using 0.025 M DTPA and Ho for Cm elution using 0.025 M DTPA with 0.025 citric acid. The tracer for Am in both instances is Tb.

Chuveleva, E.A.; Kharitonov, O.V.; Firsova, L.A.

1994-11-01

396

Solvent/solute Interactions Probed by Picosecond Transient Raman Spectroscopy: a Study of S(1) 1,4-DIPHENYL -1,3-BUTADIENE and its Structural Analogues  

NASA Astrophysics Data System (ADS)

Many important chemical/biochemical reactions involve a short-lived photochemical intermediate. From a practical standpoint, understanding the behavior of such a transient species would allow effective manipulation of many chemical and biochemical processes. In this study, Raman spectroscopy on a picosecond time scale is used to examine the character of the S_1 states of several simple probe molecules and the effect(s) that different solvents have on the behavior of the excited state species in solution. We present the S_1 Raman spectra of 1,4-diphenyl-1,3-butadiene (DPB) in the series of linear alkanes pentane, hexane, heptane, octane, decane, and dodecane. DPB has virtually degenerate electronic states in the vicinity of S_1 (2 ^1A_{rm g} and 1^1B _{rm u}). The electronic state probed by the transient Raman measurements exhibits both 2^1A_{ rm g} and 1^1B _{rm u} character (i.e. a "mixed" state). It appears that a state exhibiting more 2^1A_{ rm g} character is favored by more viscous solvents while a state of significant 1^1 B_{rm u} character is preferred by less viscous solvents. We also observe very broad features (>50 cm ^{-1}) in the S_1 Raman spectra that are associated with motions of the butadiene portion of the molecule. In order to verify that these broad bands arise from a distribution of s-trans conformers in DPB, we have obtained the transient Raman spectra of 1,4-diphenyl-1,3 - cyclopentadiene (DPCP), a "stiff" analogue of DPB. As predicted, the DPCP spectra contain only sharp bands. We also provide evidence for assigning the lowest excited singlet state of DPCP in solution as the 1B state. We evaluate the effect of geometrical constraints on the photophysics of DPCP by obtaining the S _1 Raman spectra of 1,2,3,4-tetraphenyl-1,3 -cyclopentadiene (TPCP) in solution. The addition of the extra phenyl rings to DPCP forces the molecule to take on a non-planar geometry. We confirm that the viscosity -dependent S_1 lifetime of TPCP is due to a photocyclization reaction.

Morris, Daniel Lamon, Jr.

1995-01-01