Space weather monitoring by ground-based means carried out in Polar Geophysical Center at Arctic and Antarctic Research Institute

NASA Astrophysics Data System (ADS)

Janzhura, Alexander

A real-time information on geophysical processes in polar regions is very important for goals of Space Weather monitoring by the ground-based means. The modern communication systems and computer technology makes it possible to collect and process the data from remote sites without significant delays. A new acquisition equipment based on microprocessor modules and reliable in hush climatic conditions was deployed at the Roshydromet networks of geophysical observations in Arctic and is deployed at observatories in Antarctic. A contemporary system for on-line collecting and transmitting the geophysical data from the Arctic and Antarctic stations to AARI has been realized and the Polar Geophysical Center (PGC) arranged at AARI ensures the near-real time processing and analyzing the geophysical information from 11 stations in Arctic and 5 stations in Antarctic. The space weather monitoring by the ground based means is one of the main tasks standing before the Polar Geophysical Center. As studies by Troshichev and Janzhura, [2012] showed, the PC index characterizing the polar cap magnetic activity appeared to be an adequate indicator of the solar wind energy that entered into the magnetosphere and the energy that is accumulating in the magnetosphere. A great advantage of the PC index application over other methods based on satellite data is a permanent on-line availability of information about magnetic activity in both northern and southern polar caps. A special procedure agreed between Arctic and Antarctic Research Institute (AARI) and Space Institute of the Danish Technical University (DTUSpace) ensures calculation of the unified PC index in quasi-real time by magnetic data from the Thule and Vostok stations (see public site: http://pc-index.org). The method for estimation of AL and Dst indices (as indicators of state of the disturbed magnetosphere) based on data on foregoing PC indices has been elaborated and testified in the Polar Geophysical Center. It is demonstrated that the PC index can be successfully used to monitor the state of the magnetosphere (space weather monitoring) and the readiness of the magnetosphere to producing substorm or storm (space weather nowcasting).

Infrared polarimetry of Mrk 231: scattering off hot dust grains in the central core

NASA Astrophysics Data System (ADS)

Lopez-Rodriguez, E.; Packham, C.; Jones, T. J.; Siebenmorgen, R.; Roche, P. F.; Levenson, N. A.; Alonso-Herrero, A.; Perlman, E.; Ichikawa, K.; Ramos Almeida, C.; González-Martín, O.; Nikutta, R.; Martinez-Paredez, M.; Shenoy, D.; Gordon, M. S.; Telesco, C. M.

2017-01-01

We present high-angular (0.17-0.35 arcsec) resolution imaging polarimetric observations of Mrk 231 in the 3.1 μm filter using MMT-Pol on the 6.5-m MMT, and in the 8.7, 10.3, and 11.6 μm filters using CanariCam on the 10.4-m Gran Telescopio CANARIAS. In combination with already published observations, we compile the 1-12 μm total and polarized nuclear spectral energy distribution (SED). The total flux SED in the central 400 pc is explained as the combination of (1) a hot (731 ± 4 K) dusty structure, directly irradiated by the central engine, which is at 1.6 ± 0.1 pc away and attributed to be in the pc-scale polar region, (2) an optically-thick, smooth and disc-like dusty structure (`torus') with an inclination of 48° ± 23° surrounding the central engine, and (3) an extinguished (AV = 36 ± 5 mag) starburst component. The polarized SED decreases from 0.77 ± 0.14 per cent at 1.2 μm to 0.31 ± 0.15 per cent at 11.6 μm and follows a power-law function, λ˜0.57. The polarization angle remains constant (˜108°) in the 1-12 μm wavelength range. The dominant polarization mechanism is explained as scattering-off hot dust grains in the pc-scale polar regions.

Non-covalent interaction between Cu-phthalocyanine and methanato borondifluoride derivatives in two different medium

NASA Astrophysics Data System (ADS)

Pal, Chiranjit; Chaudhuri, Tandrima; Chattopdhyay, Subrata; Banerjee, Manas

2017-04-01

This study sort out chemical physics of non-covalent interaction between Copper phthalocyanine (CuPC) with Methanato borondifluoride derivatives (MBDF) in chloroform and ethanol. Formation of isosbestic points indicated stable ground state equilibrium between CuPC and MBDF, association ability were more pronounced in less polar chloroform. Interesting overall parallel orientation of MBDF over CuPC in gas phase geometries indicated that fluorine centre of MBDF lying just above the Cu-centre of CuPC. Thus strong interaction between Cu(II)- and F- centre could not be overruled and was also established by NBO calculation. TDDFT along with FMO features and heat of reaction values clearly designated the existence of π-π interaction and effect of solvent polarity on that interaction.

Real-time multi-target ranging based on chaotic polarization laser radars in the drive-response VCSELs.

PubMed

Zhong, Dongzhou; Xu, Geliang; Luo, Wei; Xiao, Zhenzhen

2017-09-04

According to the principle of complete chaos synchronization and the theory of Hilbert phase transformation, we propose a novel real-time multi-target ranging scheme by using chaotic polarization laser radar in the drive-response vertical-cavity surface-emitting lasers (VCSELs). In the scheme, to ensure each polarization component (PC) of the master VCSEL (MVCSEL) to be synchronized steadily with that of the slave VCSEL, the output x-PC and y-PC from the MVCSEL in the drive system and those in the response system are modulated by the linear electro-optic effect simultaneously. Under this condition, by simulating the influences of some key parameters of the system on the synchronization quality and the relative errors of the two-target ranging, related operating parameters can be optimized. The x-PC and the y-PC, as two chaotic radar sources, are used to implement the real-time ranging for two targets. It is found that the measured distances of the two targets at arbitrary position exhibit strong real-time stability and only slight jitter. Their resolutions are up to millimeters, and their relative errors are very small and less than 2.7%.

A critical note on the IAGA-endorsed Polar Cap (PC) indices: excessive excursions in the real-time index values

NASA Astrophysics Data System (ADS)

Stauning, Peter

2018-04-01

The Polar Cap (PC) indices were approved by the International Association for Geomagnetism and Aeronomy (IAGA) in 2013 and made available at the web portal http://pcindex.org holding prompt (real-time) as well as archival index values. The present note provides the first reported examination of the validity of the IAGA-endorsed method to generate real-time PC index values. It is demonstrated that features of the derivation procedure defined by Janzhura and Troshichev (2011) may cause considerable excursions in the real-time PC index values compared to the final index values. In examples based on occasional downloads of index values, the differences between real-time and final values of PC indices were found to exceed 3 mV m-1, which is a magnitude level that may indicate (or hide) strong magnetic storm activity.

Band structure of one-dimensional photonic crystal with graphene layers using the Fresnel coefficients method

NASA Astrophysics Data System (ADS)

Jafari, A.; Rahmat, A.

2018-04-01

In this paper, we have calculated the band structure of an instance of one-dimensional photonic crystal (1DPC) composed of double-layered dielectrics via the Fresnel coefficients method. Then, we supposed the addition of a thin layer of graphene to each dielectric layer and the given photonic crystal (PC) composed of dielectric-graphene composites. The effects of graphene layers on the PC band structure were evaluated. We found out that according to the effective medium theory unlike the TE polarization, the electric permittivity of the dielectric layers changed at TM polarization. As such, the band structure of PC for TM polarization changed, too. Moreover, instead of bandgap related to “zero averaged refractive index” an approximately omnidirectional bandgap appeared and a related bandgap to “𝜀 = 0” disappeared. In addition, a new angular gap branch appeared at a new frequency at TM polarization in which the width of gap increased as the angle increased.

Mid-infrared imaging- and spectro-polarimetric subarcsecond observations of NGC 1068

NASA Astrophysics Data System (ADS)

Lopez-Rodriguez, E.; Packham, C.; Roche, P. F.; Alonso-Herrero, A.; Díaz-Santos, T.; Nikutta, R.; González-Martín, O.; Álvarez, C. A.; Esquej, P.; Espinosa, J. M. Rodríguez; Perlman, E.; Ramos Almeida, C.; Telesco, C. M.

2016-06-01

We present subarcsecond 7.5-13 μm imaging- and spectro-polarimetric observations of NGC 1068 using CanariCam on the 10.4-m Gran Telescopio CANARIAS. At all wavelengths, we find: (1) A 90 × 60 pc extended polarized feature in the northern ionization cone, with a uniform ˜44° polarization angle. Its polarization arises from dust and gas emission in the ionization cone, heated by the active nucleus and jet, and further extinguished by aligned dust grains in the host galaxy. The polarization spectrum of the jet-molecular cloud interaction at ˜24 pc from the core is highly polarized, and does not show a silicate feature, suggesting that the dust grains are different from those in the interstellar medium. (2) A southern polarized feature at ˜9.6 pc from the core. Its polarization arises from a dust emission component extinguished by a large concentration of dust in the galaxy disc. We cannot distinguish between dust emission from magnetically aligned dust grains directly heated by the jet close to the core, and aligned dust grains in the dusty obscuring material surrounding the central engine. Silicate-like grains reproduce the polarized dust emission in this feature, suggesting different dust compositions in both ionization cones. (3) An upper limit of polarization degree of 0.3 per cent in the core. Based on our polarization model, the expected polarization of the obscuring dusty material is ≲0.1 per cent in the 8-13 μm wavelength range. This low polarization may be arising from the passage of radiation through aligned dust grains in the shielded edges of the clumps.

Switchable multiwavelength erbium-doped photonic crystal fiber ring laser based on a length of polarization-maintaining photonic crystal fiber

NASA Astrophysics Data System (ADS)

Cheng, Jianqun; Ruan, Shuangchen

2011-11-01

A switchable multi-wavelength Erbium-doped photonic crystal fiber (ED-PCF) ring laser based on a length of polarization-maintaining photonic crystal fiber(PM-PCF) is presented and demonstrated experimentally. A segment of ED-PCF is used as linear gain medium in the resonant cavity. Due to the polarization hole burning (PHB) caused by the PM-PCF and a polarization controller (PC), the laser can operate in stable dual- or triple- wavelength modes at room temperature. The optical signal-to-noise ratio (OSNR) of the laser without any wavelength-selective components is greater than 30 dB. The amplitude variations of lasing peaks in ten minutes are less than 0.26dB for two different operating modes.

Switchable single-longitudinal-mode dual-wavelength erbium-doped fiber ring laser based on one polarization-maintaining fiber Bragg grating incorporating saturable absorber and feedback fiber loop

NASA Astrophysics Data System (ADS)

Feng, Suchun; Xu, Ou; Lu, Shaohua; Ning, Tigang; Jian, Shuisheng

2009-06-01

Switchable single-longitudinal-mode (SLM) dual-wavelength erbium-doped fiber ring laser based on one polarization-maintaining fiber Bragg grating (PMFBG) is demonstrated. Due to the enhancement of the polarization hole burning (PHB) by the PMFBG, the laser can be designed to operate in stable dual-wavelength or wavelength-switching modes with a wavelength spacing of 0.336 nm at room temperature by adjusting a polarization controller (PC). The stable SLM operation is guaranteed by a compound-ring cavity and a saturable absorber (SA). The optical signal-to-noise ratio (OSNR) is over 45 dB. The amplitude variation in nearly one and half an hour is less than 0.2 dB.

Switchable multiwavelength erbium-doped photonic crystal fiber ring laser based on a length of polarization-maintaining photonic crystal fiber

NASA Astrophysics Data System (ADS)

Cheng, Jianqun; Ruan, Shuangchen

2012-03-01

A switchable multi-wavelength Erbium-doped photonic crystal fiber (ED-PCF) ring laser based on a length of polarization-maintaining photonic crystal fiber(PM-PCF) is presented and demonstrated experimentally. A segment of ED-PCF is used as linear gain medium in the resonant cavity. Due to the polarization hole burning (PHB) caused by the PM-PCF and a polarization controller (PC), the laser can operate in stable dual- or triple- wavelength modes at room temperature. The optical signal-to-noise ratio (OSNR) of the laser without any wavelength-selective components is greater than 30 dB. The amplitude variations of lasing peaks in ten minutes are less than 0.26dB for two different operating modes.

PrPC Undergoes Basal to Apical Transcytosis in Polarized Epithelial MDCK Cells

PubMed Central

Arkhipenko, Alexander; Syan, Sylvie; Victoria, Guiliana Soraya

2016-01-01

The Prion Protein (PrP) is an ubiquitously expressed glycosylated membrane protein attached to the external leaflet of the plasma membrane via a glycosylphosphatidylinositol anchor (GPI). While the misfolded PrPSc scrapie isoform is the infectious agent of prion disease, the cellular isoform (PrPC) is an enigmatic protein with unclear function. Of interest, PrP localization in polarized MDCK cells is controversial and its mechanism of trafficking is not clear. Here we investigated PrP traffic in MDCK cells polarized on filters and in three-dimensional MDCK cysts, a more physiological model of polarized epithelia. We found that, unlike other GPI-anchored proteins (GPI-APs), PrP undergoes basolateral-to-apical transcytosis in fully polarized MDCK cells. Following this event full-length PrP and its cleavage fragments are segregated in different domains of the plasma membrane in polarized cells in both 2D and 3D cultures. PMID:27389581

Observation of spin-polarized photoconductivity in (Ga,Mn)As/GaAs heterojunction without magnetic field

PubMed Central

Wu, Qing; Liu, Yu; Wang, Hailong; Li, Yuan; Huang, Wei; Zhao, Jianhua; Chen, Yonghai

2017-01-01

In the absent of magnetic field, we have observed the anisotropic spin polarization degree of photoconduction (SPD-PC) in (Ga,Mn)As/GaAs heterojunction. We think three kinds of mechanisms contribute to the magnetic related signal, (i) (Ga,Mn)As self-producing due to the valence band polarization, (ii) unequal intensity of left and right circularly polarized light reaching to GaAs layer to excite unequal spin polarized carriers in GaAs layer, and (iii) (Ga,Mn)As as the spin filter layer for spin transport from GaAs to (Ga,Mn)As. Different from the previous experiments, the influence coming from the Zeeman splitting induced by an external magnetic field can be avoided here. While temperature dependence experiment indicates that the SPD-PC is mixed with the magnetic uncorrelated signals, which may come from current induced spin polarization. PMID:28084437

Effect of Magnesium Ion on the Zinc Electrodeposition from Acidic Sulfate Electrolyte

NASA Astrophysics Data System (ADS)

Tian, Lin; Xie, Gang; Yu, Xiao-Hua; Li, Rong-Xing; Zeng, Gui-Sheng

2012-02-01

The effects of Mg2+ ion on the zinc electrodeposition were systematically investigated in sulfuric acid solution through the characterizations of current efficiency (CE), power consumption (PC), deposit morphology, cathodic polarization, and cyclic voltammetry. The results demonstrate that there is no significant influence on CE and PC in the Mg2+ concentration range of 1 to 10 g L-1, but with a drastic decrease of the CE and rapid increase of PC at Mg2+ ion concentration above 15 g L-1. Based on the morphology observation and polarization curves, the presence of Mg2+ ions could also induce the coarse surface on the electrodeposited zinc accompanying the enhancement of the cathodic polarization, which becomes more distinct at a high concentration above 15 g L-1. Furthermore, hydrogen evolution could be promoted with the existence of Mg2+ ions according to cyclic voltammograms.

Location of γ-ray Flare Emission in the Jet of the BL Lacertae Object OJ287 More than 14 pc from the Central Engine

NASA Astrophysics Data System (ADS)

Agudo, Iván; Jorstad, Svetlana G.; Marscher, Alan P.; Larionov, Valeri M.; Gómez, José L.; Lähteenmäki, Anne; Gurwell, Mark; Smith, Paul S.; Wiesemeyer, Helmut; Thum, Clemens; Heidt, Jochen; Blinov, Dmitriy A.; D'Arcangelo, Francesca D.; Hagen-Thorn, Vladimir A.; Morozova, Daria A.; Nieppola, Elina; Roca-Sogorb, Mar; Schmidt, Gary D.; Taylor, Brian; Tornikoski, Merja; Troitsky, Ivan S.

2011-01-01

We combine time-dependent multi-waveband flux and linear polarization observations with submilliarcsecond-scale polarimetric images at λ = 7 mm of the BL Lacertae type blazar OJ287 to locate the γ-ray emission in prominent flares in the jet of the source >14 pc from the central engine. We demonstrate a highly significant correlation between the strongest γ-ray and millimeter-wave flares through Monte Carlo simulations. The two reported γ-ray peaks occurred near the beginning of two major millimeter-wave outbursts, each of which is associated with a linear polarization maximum at millimeter wavelengths. Our very long baseline array observations indicate that the two millimeter-wave flares originated in the second of two features in the jet that are separated by >14 pc. The simultaneity of the peak of the higher-amplitude γ-ray flare and the maximum in polarization of the second jet feature implies that the γ-ray and millimeter-wave flares are cospatial and occur >14 pc from the central engine. We also associate two optical flares, accompanied by sharp polarization peaks, with the two γ-ray events. The multi-waveband behavior is most easily explained if the γ-rays arise from synchrotron self-Compton scattering of optical photons from the flares. We propose that flares are triggered by interaction of moving plasma blobs with a standing shock. The γ-ray and optical emission is quenched by inverse Compton losses as synchrotron photons from the newly shocked plasma cross the emission region. The millimeter-wave polarization is high at the onset of a flare, but decreases as the electrons emitting at these wavelengths penetrate less polarized regions.

LOCATION OF {gamma}-RAY FLARE EMISSION IN THE JET OF THE BL LACERTAE OBJECT OJ287 MORE THAN 14 pc FROM THE CENTRAL ENGINE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Agudo, Ivan; Jorstad, Svetlana G.; Marscher, Alan P.

We combine time-dependent multi-waveband flux and linear polarization observations with submilliarcsecond-scale polarimetric images at {lambda} = 7 mm of the BL Lacertae type blazar OJ287 to locate the {gamma}-ray emission in prominent flares in the jet of the source >14 pc from the central engine. We demonstrate a highly significant correlation between the strongest {gamma}-ray and millimeter-wave flares through Monte Carlo simulations. The two reported {gamma}-ray peaks occurred near the beginning of two major millimeter-wave outbursts, each of which is associated with a linear polarization maximum at millimeter wavelengths. Our very long baseline array observations indicate that the two millimeter-wavemore » flares originated in the second of two features in the jet that are separated by >14 pc. The simultaneity of the peak of the higher-amplitude {gamma}-ray flare and the maximum in polarization of the second jet feature implies that the {gamma}-ray and millimeter-wave flares are cospatial and occur >14 pc from the central engine. We also associate two optical flares, accompanied by sharp polarization peaks, with the two {gamma}-ray events. The multi-waveband behavior is most easily explained if the {gamma}-rays arise from synchrotron self-Compton scattering of optical photons from the flares. We propose that flares are triggered by interaction of moving plasma blobs with a standing shock. The {gamma}-ray and optical emission is quenched by inverse Compton losses as synchrotron photons from the newly shocked plasma cross the emission region. The millimeter-wave polarization is high at the onset of a flare, but decreases as the electrons emitting at these wavelengths penetrate less polarized regions.« less

Switchable single-longitudinal-mode dual-wavelength erbium-doped fiber laser based on one polarization-maintaining fiber Bragg grating incorporating saturable absorber

NASA Astrophysics Data System (ADS)

Feng, Suchun; Xu, Ou; Lu, Shaohua; Chen, Ming; Jian, Shuisheng

2009-08-01

Switchable single-longitudinal-mode (SLM) dual-wavelength erbium-doped fiber laser at room temperature is demonstrated. One fiber Bragg grating (FBG) directly written in a polarization-maintaining and photosensitive erbiumdoped fiber (PMPEDF) as the wavelength-selective component is used in a linear laser cavity. Due to the polarization hole burning (PHB) enhanced by the polarization-maintaining fiber Bragg grating (PMFBG), the laser can be designed to operate in stable dual-wavelength or wavelength-switching modes with a wavelength spacing of 0.202 nm by adjusting a polarization controller (PC). The stable SLM operation is guaranteed by a saturable absorber (SA). The optical signal-tonoise ratio (OSNR) of the laser is over 40 dB. The amplitude variation in nearly one and half an hour is less than 0.5 dB for both wavelengths.

Magnetic moment enhancement and spin polarization switch of the manganese phthalocyanine molecule on an IrMn(100) surface

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, X.; National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047; Wang, B.

2014-07-21

The geometric, electronic, and magnetic structures of a manganese phthalocyanine (MnPc) molecule on an antiferromagnetic IrMn(100) surface are studied by density functional theory calculations. Two kinds of orientation of the adsorbed MnPc molecule are predicted to coexist due to molecular self-assembly on the surface—a top-site geometry with the Mn–N bonds aligned along the 〈100〉 direction, and a hollow-site orientation in which the Mn–N bonds are parallel to the 〈110〉 direction. The MnPc molecule is antiferromagnetically coupled to the substrate at the top site with a slight reduction in the magnetic moment of the Mn atom of the MnPc molecule (Mn{submore » mol}). In contrast, the magnetic moment of the Mn{sub mol} is enhanced to 4.28 μB at the hollow site, a value larger than that in the free MnPc molecule (3.51 μB). Molecular distortion induced by adsorption is revealed to be responsible for the enhancement of the magnetic moment. Furthermore, the spin polarization of the Mn{sub mol} atom at around the Fermi level is found to change from negative to positive through an elongation of the Mn–N bonds of the MnPc. We propose that a reversible switch of the low/high magnetic moment and negative/positive spin polarization might be realized through some mechanical engineering methods.« less

Carrier and polarization dynamics in monolayer MoS2: temperature and power dependence

NASA Astrophysics Data System (ADS)

Urbaszek, Bernhard; Lagarde, D.; Bouet, L.; Amand, T.; Marie, X.; Zhu, C. R.; Liu, B. L.; Tan, P. H.

2014-03-01

In monolayer (ML) MoS2 optical transitions across the direct bandgap are governed by chiral selection rules, allowing optical k-valley initialization. Here we present the first time resolved photoluminescence (PL) polarization measurements in MoS2 MLs, providing vital information on the electron valley dynamics. Using quasi-resonant excitation of the A-exciton transitions, we can infer that the PL decays within τ ~= 4ps. The PL polarization of Pc ~ 60 % remains nearly constant in time for experiments from 4K - 300K, a necessary condition for the success of future Valley Hall experiments. τ does not vary significantly over this temperature range. This is surprising when considering the decrease of Pc in continuous wave experiments when going from 4K to 300K reported in the literature. By tuning the laser following the shift of the A-exciton resonance with temperature we are able to recover at 300K ~ 80 % of the polarization observed at 4K. For pulsed laser excitation, we observe a decrease of Pc with increasing laser power at all temperatures.

Magnetosphere on May 11, 1999, the day the solar wind almost disappeared: II. Magnetic pulsations in space and on the ground

NASA Astrophysics Data System (ADS)

Le, G.; Chi, P. J.; Goedecke, W.; Russell, C. T.; Szabo, A.; Petrinec, S. M.; Angelopoulos, V.; Reeves, G. D.; Chun, F. K.

2000-08-01

Simultaneous observations by Wind and IMP-8 in the upstream region on May 11, 1999, when the solar wind density was well below its usual values and the IMF was generally weakly northward, indicate there were upstream waves present in the foreshock, but wave power was an order of magnitude weaker than usual due to an extremely weak bow shock and tenuous solar wind plasma. Magnetic pulsations in the magnetosphere have been observed in the magnetic field data from Polar and at mid-latitude ground stations. By comparing May 11 with a control day under normal solar wind conditions and with a similar foreshock geometry, we find that the magnetosphere was much quieter than usual. The Pc 3-4 waves were nearly absent in the dayside magnetosphere both at Polar and as seen at mid-latitude ground stations even through the foreshock geometry was favorable for the generation of these waves. Since the solar wind speed was not unusual on this day, these observations suggest that it is the Mach number of the solar wind flow relative to the magnetosphere that controls the amplitude of Pc 3-4 waves in the magnetosphere.

A Polarimetric Investigation on Interstellar Dust Within 50-PARSECS from the Sun

NASA Astrophysics Data System (ADS)

Leroy, J. L.

1993-07-01

We have analyzed the polarization catalogue, for 1000 stars closer than 50 Pc, which has been presented in a companion paper. Although the accuracy of the measurements is generally very good (better than 0.02% for more than 700 stars), the catalogue contains essentially unpolarized stars, which is to be related to the well known depletion of dust in the Sun's vicinity. However, setting apart some stars which are known to display intrinsic polarization (e.g. several Ap magnetic variables), we have been able to select 25 stars whose polarization is indisputable. But, looking in more detail at the (presently available) data on the distance of this sample reveals that, in almost all the cases, the distances have been under-estimated. While this result will require a confirmation with the help of the Hipparcos parallaxes, we can already say that we fully confirm the main result of the preceding investigation on this topic by Tinbergen (1982), namely the complete depletion of dust within 35 pc from the Sun. Actually, we find that the dust signature begins at 40-50 pc in a few cases, but more much frequently at 70 to 100 pc, which seems to be the boundary of the local Bubble, as far as dust is concerned. We cannot confirm the previous detection by Tinbergen of a faint, near-by dusty region around l = 0°, b = -20°. Altogether, the picture given by the polarization analysis is consistent (although more sensitive) with the data derived from reddening measurements, and, to a lesser extent, with the investigations based on the measurements of interstellar absorption lines. Extending the polarization measurements to the 50-100 pc zone would provide a very precise picture of the location of those dust clouds which appear, here and there, as one gets out from the local Bubble.

Rethinking the polar cap: Eccentric dipole structuring of ULF power at the highest corrected geomagnetic latitudes

NASA Astrophysics Data System (ADS)

Urban, Kevin D.; Gerrard, Andrew J.; Lanzerotti, Louis J.; Weatherwax, Allan T.

2016-09-01

The day-to-day evolution and statistical features of Pc3-Pc7 band ultralow frequency (ULF) power throughout the southern polar cap suggest that the corrected geomagnetic (CGM) coordinates do not adequately organize the observed hydromagnetic spatial structure. It is shown that that the local-time distribution of ULF power at sites along CGM latitudinal parallels exhibit fundamental differences and that the CGM latitude of a site in general is not indicative of the site's projection into the magnetosphere. Thus, ULF characteristics observed at a single site in the polar cap cannot be freely generalized to other sites of similar CGM latitude but separated in magnetic local time, and the inadequacy of CGM coordinates in the polar cap has implications for conjugacy/mapping studies in general. In seeking alternative, observationally motivated systems of "polar cap latitudes," it is found that eccentric dipole (ED) coordinates have several strengths in organizing the hydromagnetic spatial structure in the polar cap region. ED latitudes appear to better classify the local-time ULF power in both magnitude and morphology and better differentiate the "deep polar cap" (where the ULF power is largely UT dependent and nearly free of local-time structure) from the "peripheral polar cap" (where near-magnetic noon pulsations dominate at lower and lower frequencies as one increases in ED latitude). Eccentric local time is shown to better align the local-time profiles in the magnetic east component over several PcX bands but worsen in the magnetic north component. It is suggested that a hybrid ED-CGM coordinate system might capture the strengths of both CGM and ED coordinates. It is shown that the local-time morphology of median ULF power at high-latitude sites is dominantly driven by where they project into the magnetosphere, which is best quantified by their proximity to the low-altitude cusp on the dayside (which is not necessarily quantified by a site's CGM latitude), and that variations in the local-time morphology at sites similar in ED latitude are due to both geographic local-time control (relative amplification or dampening by the diurnal variation in the local ionospheric conductivity) and geomagnetic coastal effects (enhanced power in a coastally mediated direction). Regardless of cause, it is emphasized that the application of CGM latitudes in the polar cap region is not entirely meaningful and likely should be dispensed with in favor of a scheme that is in better accord with the observed hydromagnetic spatial structure.

Effect of substrates on the molecular orientation of silicon phthalocyanine dichloride thin films

NASA Astrophysics Data System (ADS)

Deng, Juzhi; Baba, Yuji; Sekiguchi, Tetsuhiro; Hirao, Norie; Honda, Mitsunori

2007-05-01

Molecular orientations of silicon phthalocyanine dichloride (SiPcCl2) thin films deposited on three different substrates have been measured by near-edge x-ray absorption fine structure (NEXAFS) spectroscopy using linearly polarized synchrotron radiation. The substrates investigated were highly oriented pyrolitic graphite (HOPG), polycrystalline gold and indium tin oxide (ITO). For thin films of about five monolayers, the polarization dependences of the Si K-edge NEXAFS spectra showed that the molecular planes of SiPcCl2 on three substrates were nearly parallel to the surface. Quantitative analyses of the polarization dependences revealed that the tilted angle on HOPG was only 2°, which is interpreted by the perfect flatness of the HOPG surface. On the other hand, the tilted angle on ITO was 26°. Atomic force microscopy (AFM) observation of the ITO surface showed that the periodicity of the horizontal roughness is of the order of a few nanometres, which is larger than the molecular size of SiPcCl2. It is concluded that the morphology of the top surface layer of the substrate affects the molecular orientation of SiPcCl2 molecules not only for mono-layered adsorbates but also for multi-layered thin films.

Comparison of Polar Cap (PC) index calculations.

NASA Astrophysics Data System (ADS)

Stauning, P.

2012-04-01

The Polar Cap (PC) index introduced by Troshichev and Andrezen (1985) is derived from polar magnetic variations and is mainly a measure of the intensity of the transpolar ionospheric currents. These currents relate to the polar cap antisunward ionospheric plasma convection driven by the dawn-dusk electric field, which in turn is generated by the interaction of the solar wind with the Earth's magnetosphere. Coefficients to calculate PCN and PCS index values from polar magnetic variations recorded at Thule and Vostok, respectively, have been derived by several different procedures in the past. The first published set of coefficients for Thule was derived by Vennerstrøm, 1991 and is still in use for calculations of PCN index values by DTU Space. Errors in the program used to calculate index values were corrected in 1999 and again in 2001. In 2005 DMI adopted a unified procedure proposed by Troshichev for calculations of the PCN index. Thus there exists 4 different series of PCN index values. Similarly, at AARI three different sets of coefficients have been used to calculate PCS indices in the past. The presentation discusses the principal differences between the various PC index procedures and provides comparisons between index values derived from the same magnetic data sets using the different procedures. Examples from published papers are examined to illustrate the differences.

Altered phospholipid metabolism in schizophrenia: a phosphorus 31 nuclear magnetic resonance spectroscopy study.

PubMed

Weber-Fahr, Wolfgang; Englisch, Susanne; Esser, Andrea; Tunc-Skarka, Nuran; Meyer-Lindenberg, Andreas; Ende, Gabriele; Zink, Mathias

2013-12-30

Phospholipid (PL) metabolism is investigated by in vivo 31P magnetic resonance spectroscopy (MRS). Inconsistent alterations of phosphocholine (PC), phosphoethanolamine (PE), glycerophosphocholine (GPC) and glycerophosphoethanolamine (GPE) have been described in schizophrenia, which might be overcome by specific editing techniques. The selective refocused insensitive nuclei-enhanced polarization transfer (RINEPT) technique was applied in a cross-sectional study involving 11 schizophrenia spectrum disorder patients (SZP) on stable antipsychotic monotherapy and 15 matched control subjects. Metabolite signals were found to be modulated by cerebrospinal fluid (CSF) content and gray matter/brain matter ratio. Corrected metabolite concentrations of PC, GPC and PE differed between patients and controls in both subcortical and cortical regions, whereas antipsychotic medication exerted only small effects. Significant correlations were found between the severity of clinical symptoms and the assessed signals. In particular, psychotic symptoms correlated with PC levels in the cerebral cortex, depression with PC levels in the cerebellum and executive functioning with GPC in the insular and temporal cortices. In conclusion, after controlling for age and tissue composition, this investigation revealed alterations of metabolite levels in SZP and correlations with clinical properties. RINEPT 31P MRS should also be applied to at-risk-mental-state patients as well as drug-naïve and chronically treated schizophrenic patients in order to enhance the understanding of longitudinal alterations of PL metabolism in schizophrenia. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Properties of copper (fluoro-)phthalocyanine layers deposited on epitaxial graphene.

PubMed

Ren, Jun; Meng, Sheng; Wang, Yi-Lin; Ma, Xu-Cun; Xue, Qi-Kun; Kaxiras, Efthimios

2011-05-21

We investigate the atomic structure and electronic properties of monolayers of copper phthalocyanines (CuPc) deposited on epitaxial graphene substrate. We focus in particular on hexadecafluorophthalocyanine (F(16)CuPc), using both theoretical and experimental (scanning tunneling microscopy - STM) studies. For the individual CuPc and F(16)CuPc molecules, we calculated the electronic and optical properties using density functional theory (DFT) and time-dependent DFT and found a red-shift in the absorption peaks of F(16)CuPc relative to those of CuPc. In F(16)CuPc, the electronic wavefunctions are more polarized toward the electronegative fluorine atoms and away from the Cu atom at the center of the molecule. When adsorbed on graphene, the molecules lie flat and form closely packed patterns: F(16)CuPc forms a hexagonal pattern with two well-ordered alternating α and β stripes while CuPc arranges into a square lattice. The competition between molecule-substrate and intermolecular van der Waals interactions plays a crucial role in establishing the molecular patterns leading to tunable electron transfer from graphene to the molecules. This transfer is controlled by the layer thickness of, or the applied voltage on, epitaxial graphene resulting in selective F(16)CuPc adsorption, as observed in STM experiments. In addition, phthalocyanine adsorption modifies the electronic structure of the underlying graphene substrate introducing intensity smoothing in the range of 2-3 eV below the Dirac point (E(D)) and a small peak in the density of states at ∼0.4 eV above E(D). © 2011 American Institute of Physics.

Possible link of sudden onset and short-time periodic pulsation of polar mesosphere summer echoes to ULF Pc5 geomagnetic pulsations and solar wind dynamic pressure enhancement

NASA Astrophysics Data System (ADS)

Lee, Y.; Kirkwood, S.; Kwak, Y. S.

2016-12-01

The EISCAT VHF incoherent scatter radar in Tromsö, Norway, makes occasional observations of electron densities and Polar Mesosphere Summer Echoes, in the summer polar D-region ionosphere. In one of those datasets, pulsating polar mesospheric summer echoes (PMSE) are observed, with periodicities in the ultra-low frequency (ULF) Pc5 band (1.6-6.7 mHz), following an abrupt increase of the radar reflectivity when a geomagnetic field excursion is started, in turn linked to dynamic pressure (Pdyn) enhancement in the solar wind. At the excursion of the magnetic field, at auroral altitudes of 90 km and above, electron density is abruptly enhanced, followed by a series of short-lived peaks, superimposed on an enhanced level. The short-lived peaks are likely a signature of transient Pc5 geomagnetic pulsations and associated energetic electron precipitation from pitch-angle scattering into the loss cone in the magnetosphere. At the same time, at altitudes around 80-90 km, a sharp increase of PMSE reflectivity occurs, 100 times greater than the increase of electron density, and is followed by pulsating PMSE reflectivity with periodicities in the Pc5 band, increasing and decreasing in magnitude during the course of the next hour. The increase of the pulsation magnitude may be attributed to an increase of high-energy electron precipitation flux ( >30 keV) penetrating to at least the height of maximum PMSE reflectivity. This study suggests that Pc5 pulsation bursts in both magnetic field and high energy electron precipitation could play a crucial role in producing PMSE fluctuations on minute-to-minute time scales.

Nanoscale Insight and Control of Structural and Electronic Properties of Organic Semiconductor / Metal Interfaces

NASA Astrophysics Data System (ADS)

Maughan, Bret

Organic semiconductor interfaces are promising materials for use in next-generation electronic and optoelectronic devices. Current models for metal-organic interfacial electronic structure and dynamics are inadequate for strongly hybridized systems. This work aims to address this issue by identifying the factors most important for understanding chemisorbed interfaces with an eye towards tuning the interfacial properties. Here, I present the results of my research on chemisorbed interfaces formed between thin-films of phthalocyanine molecules grown on monocrystalline Cu(110). Using atomically-resolved nanoscale imaging in combination with surface-sensitive photoemission techniques, I show that single-molecule level interactions control the structural and electronic properties of the interface. I then demonstrate that surface modifications aimed at controlling interfacial interactions are an effective way to tailor the physical and electronic structure of the interface. This dissertation details a systematic investigation of the effect of molecular and surface functionalization on interfacial interactions. To understand the role of molecular structure, two types of phthalocyanine (Pc) molecules are studied: non-planar, dipolar molecules (TiOPc), and planar, non-polar molecules (H2Pc and CuPc). Multiple adsorption configurations for TiOPc lead to configuration-dependent self-assembly, Kondo screening, and electronic energy-level alignment. To understand the role of surface structure, the Cu(110) surface is textured and passivated by oxygen chemisorption prior to molecular deposition, which gives control over thin-film growth and interfacial electronic structure in H2Pc and CuPc films. Overall, the work presented here demonstrates a method for understanding interfacial electronic structure of strongly hybridized interfaces, an important first step towards developing more robust models for metal-organic interfaces, and reliable, predictive tuning of interfacial properties.

Electric Charge Accumulation in Polar and Non-Polar Polymers under Electron Beam Irradiation

NASA Astrophysics Data System (ADS)

Nagasawa, Kenichiro; Honjoh, Masato; Takada, Tatsuo; Miyake, Hiroaki; Tanaka, Yasuhiro

The electric charge accumulation under an electron beam irradiation (40 keV and 60 keV) was measured by using the pressure wave propagation (PWP) method in the dielectric insulation materials, such as polar polymeric films (polycarbonate (PC), polyethylene-naphthalate (PEN), polyimide (PI), and polyethylene-terephthalate (PET)) and non-polar polymeric films (polystyrene (PS), polypropylene (PP), polyethylene (PE) and polytetrafluoroethylene (PTFE)). The PE and PTFE (non-polar polymers) showed the properties of large amount of electric charge accumulation over 50 C/m3 and long saturation time over 80 minutes. The PP and PS (non-polar polymer) showed the properties of middle amount of charge accumulation about 20 C/m3 and middle saturation time about 1 to 20 minutes. The PC, PEN, PI and PET (polar polymers) showed the properties of small amount of charge accumulation about 5 to 20 C/m3 and within short saturation time about 1.0 minutes. This paper summarizes the relationship between the properties of charge accumulation and chemical structural formula, and compares between the electro static potential distribution with negative charged polymer and its chemical structural formula.

1.7  μm band narrow-linewidth tunable Raman fiber lasers pumped by spectrum-sliced amplified spontaneous emission.

PubMed

Zhang, Peng; Wu, Di; Du, Quanli; Li, Xiaoyan; Han, Kexuan; Zhang, Lizhong; Wang, Tianshu; Jiang, Huilin

2017-12-10

A 1.7 μm band tunable narrow-linewidth Raman fiber laser based on spectrally sliced amplified spontaneous emission (SS-ASE) and multiple filter structures is proposed and experimentally demonstrated. In this scheme, an SS-ASE source is employed as a pump source in order to avoid stimulated Brillouin scattering. The ring configuration includes a 500 m long high nonlinear optical fiber and a 10 km long dispersion shifted fiber as the gain medium. A segment of un-pumped polarization-maintaining erbium-doped fiber is used to modify the shape of the spectrum. Furthermore, a nonlinear polarization rotation scheme is applied as the wavelength selector to generate lasers. A high-finesse ring filter and a ring filter are used to narrow the linewidth of the laser, respectively. We demonstrate tuning capabilities of a single laser over 28 nm between 1652 nm and 1680 nm by adjusting the polarization controller (PC) and tunable filter. The tunable laser has a 0.023 nm effective linewidth with the high-finesse ring filter. The stable multi-wavelength laser operation of up to four wavelengths can be obtained by adjusting the PC carefully when the pump power increases.

Pavement cells: a model system for non-transcriptional auxin signalling and crosstalks

PubMed Central

Chen, Jisheng; Wang, Fei; Zheng, Shiqin; Xu, Tongda; Yang, Zhenbiao

2015-01-01

Auxin (indole acetic acid) is a multifunctional phytohormone controlling various developmental patterns, morphogenetic processes, and growth behaviours in plants. The transcription-based pathway activated by the nuclear TRANSPORT INHIBITOR RESISTANT 1/auxin-related F-box auxin receptors is well established, but the long-sought molecular mechanisms of non-transcriptional auxin signalling remained enigmatic until very recently. Along with the establishment of the Arabidopsis leaf epidermal pavement cell (PC) as an exciting and amenable model system in the past decade, we began to gain insight into non-transcriptional auxin signalling. The puzzle-piece shape of PCs forms from intercalated or interdigitated cell growth, requiring local intra- and inter-cellular coordination of lobe and indent formation. Precise coordination of this interdigitated pattern requires auxin and an extracellular auxin sensing system that activates plasma membrane-associated Rho GTPases from plants and subsequent downstream events regulating cytoskeletal reorganization and PIN polarization. Apart from auxin, mechanical stress and cytokinin have been shown to affect PC interdigitation, possibly by interacting with auxin signals. This review focuses upon signalling mechanisms for cell polarity formation in PCs, with an emphasis on non-transcriptional auxin signalling in polarized cell expansion and pattern formation and how different auxin pathways interplay with each other and with other signals. PMID:26047974

Multi-station basis for Polar Cap (PC) indices: ensuring credibility and operational reliability

NASA Astrophysics Data System (ADS)

Stauning, Peter

2018-02-01

The Polar Cap (PC) indices, PCN (North) and PCS (South) are based on polar geomagnetic observations from Qaanaaq (Thule) and Vostok, respectively, processed to measure the transpolar plasma convection that may seriously affect space weather conditions. To establish reliable space weather forecasts based on PC indices, and also to ensure credibility of their use for scientific analyses of solar wind-magnetosphere interactions, additional sources of data for the PC indices are investigated. In the search for alternative index sources, objective quality criteria are established here to be used for the selection among potential candidates. These criteria are applied to existing PC index series to establish a quality scale. In the Canadian region, the data from Resolute Bay magnetometer are shown to provide alternative PCN indices of adequate quality. In Antarctica, the data from Concordia Dome-C observatory are shown to provide basis for alternative PCS indices. In examples to document the usefulness of these alternative index sources it is shown that PCN indices in a real-time version based on magnetometer data from Resolute Bay could have given 6 h of early warning, of which the last 2 h were "red alert", up to the onset of the strong substorm event on 13 March 1989 that caused power outage in Quebec. The alternative PCS indices based on data from Dome-C have helped to disclose that presently available Vostok-based PCS index values are corrupted throughout most of 2011.

Real-time polarization-sensitive optical coherence tomography data processing with parallel computing

PubMed Central

Liu, Gangjun; Zhang, Jun; Yu, Lingfeng; Xie, Tuqiang; Chen, Zhongping

2010-01-01

With the increase of the A-line speed of optical coherence tomography (OCT) systems, real-time processing of acquired data has become a bottleneck. The shared-memory parallel computing technique is used to process OCT data in real time. The real-time processing power of a quad-core personal computer (PC) is analyzed. It is shown that the quad-core PC could provide real-time OCT data processing ability of more than 80K A-lines per second. A real-time, fiber-based, swept source polarization-sensitive OCT system with 20K A-line speed is demonstrated with this technique. The real-time 2D and 3D polarization-sensitive imaging of chicken muscle and pig tendon is also demonstrated. PMID:19904337

Homophilic and heterophilic polycystin 1 interactions regulate E-cadherin recruitment and junction assembly in MDCK cells

PubMed Central

Streets, Andrew J.; Wagner, Bart E.; Harris, Peter C.; Ward, Christopher J.; Ong, Albert C. M.

2009-01-01

Summary Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited human renal disease and is caused by mutations in two genes, PKD1 (85%) and PKD2 (15%). Cyst epithelial cells are characterised by a complex cellular phenotype including changes in proliferation, apoptosis, basement membrane composition and apicobasal polarity. Since polycystin 1 (PC1), the PKD1 protein, has been located in the basolateral membrane of kidney epithelial cells, we hypothesised that it might have a key role in mediating or stabilising cell-cell interactions. In non-ciliated L929 cells, stable or transient surface expression of the PC1 extracellular domain was sufficient to confer an adhesive phenotype and stimulate junction formation. In MDCK cells, we found that PC1 was recruited to the lateral membranes coincident with E-cadherin within 30 minutes after a `calcium switch'. Recruitment of both proteins was significantly delayed when cells were treated with a PC1 blocking antibody raised to the PKD domains. Finally, PC1 and E-cadherin could be coimmunoprecipitated together from MDCK cells. We conclude that PC1 has a key role in initiating junction formation via initial homophilic interactions and facilitates junction assembly and the establishment of apicobasal polarity by E-cadherin recruitment. PMID:19351715

Simultaneous observation of Pc 3-4 pulsations in the solar wind and in the earth's magnetosphere

NASA Technical Reports Server (NTRS)

Engebretson, M. J.; Zanetti, L. J.; Potemra, T. A.; Baumjohann, W.; Luehr, H.; Acuna, M. H.

1987-01-01

The equatorially orbiting Active Magnetospheric Particle Tracer Explorers CCE and IRM satellites have made numerous observations of Pc 3-4 magnetic field pulsations (10-s to 100-s period) simultaneously at locations upstream of the earth's bow shock and inside the magnetosphere. These observations show solar wind/IMF control of two categories of dayside magnetospheric pulsations. Harmonically structured, azimuthally polarized pulsations are commonly observed from L = 4 to 9 in association with upstream waves. More monochromatic compressional pulsations are clearly evident on occasion, with periods identical to those observed simultaneously in the solar wind. The observations reported here are consistent with a high-latitude (cusp) entry mechanism for wave energy related to harmonically structured pulsations.

Motion-artifact-robust, polarization-resolved second-harmonic-generation microscopy based on rapid polarization switching with electro-optic Pockells cell and its application to in vivo visualization of collagen fiber orientation in human facial skin

PubMed Central

Tanaka, Yuji; Hase, Eiji; Fukushima, Shuichiro; Ogura, Yuki; Yamashita, Toyonobu; Hirao, Tetsuji; Araki, Tsutomu; Yasui, Takeshi

2014-01-01

Polarization-resolved second-harmonic-generation (PR-SHG) microscopy is a powerful tool for investigating collagen fiber orientation quantitatively with low invasiveness. However, the waiting time for the mechanical polarization rotation makes it too sensitive to motion artifacts and hence has hampered its use in various applications in vivo. In the work described in this article, we constructed a motion-artifact-robust, PR-SHG microscope based on rapid polarization switching at every pixel with an electro-optic Pockells cell (PC) in synchronization with step-wise raster scanning of the focus spot and alternate data acquisition of a vertical-polarization-resolved SHG signal and a horizontal-polarization-resolved one. The constructed PC-based PR-SHG microscope enabled us to visualize orientation mapping of dermal collagen fiber in human facial skin in vivo without the influence of motion artifacts. Furthermore, it implied the location and/or age dependence of the collagen fiber orientation in human facial skin. The robustness to motion artifacts in the collagen orientation measurement will expand the application scope of SHG microscopy in dermatology and collagen-related fields. PMID:24761292

On the Factors Determining the Eruptive Character of Solar Flares

NASA Astrophysics Data System (ADS)

Baumgartner, Christian; Thalmann, Julia K.; Veronig, Astrid M.

2018-02-01

We investigated how the magnetic field in solar active regions (ARs) controls flare activity, i.e., whether a confined or eruptive flare occurs. We analyzed 44 flares of GOES class M5.0 and larger that occurred during 2011–2015. We used 3D potential magnetic field models to study their location (using the flare distance from the flux-weighted AR center d FC) and the strength of the magnetic field in the corona above (via decay index n and flux ratio). We also present a first systematic study of the orientation of the coronal magnetic field, using the orientation φ of the flare-relevant polarity inversion line as a measure. We analyzed all quantities with respect to the size of the underlying dipole field, characterized by the distance between the opposite-polarity centers, d PC. Flares originating from underneath the AR dipole (d FC/d PC < 0.5) tend to be eruptive if launched from compact ARs (d PC ≤ 60 Mm) and confined if launched from extended ARs. Flares ejected from the periphery of ARs (d FC/d PC > 0.5) are predominantly eruptive. In confined events, the flare-relevant field adjusts its orientation quickly to that of the underlying dipole with height (Δφ ≳ 40° until the apex of the dipole field), in contrast to eruptive events where it changes more slowly with height. The critical height for torus instability, h crit = h(n = 1.5), discriminates best between confined (h crit ≳ 40 Mm) and eruptive flares (h crit ≲ 40 Mm). It discriminates better than Δφ, implying that the decay of the confining field plays a stronger role than its orientation at different heights.

Survey of Ionospheric Pc3-5 ULF Wave Signatures in SuperDARN High Time Resolution Data

NASA Astrophysics Data System (ADS)

Shi, X.; Ruohoniemi, J. M.; Baker, J. B. H.; Lin, D.; Bland, E. C.; Hartinger, M. D.; Scales, W. A.

2018-05-01

Ionospheric signatures of ultralow frequency (ULF) wave in the Pc3-5 band (1.7-40.0 mHz) were surveyed using ˜6-s resolution data from Super Dual Auroral Radar Network (SuperDARN) radars in the Northern Hemisphere from 2010 to 2016. Numerical experiments were conducted to derive wave period-dependent thresholds for automated detection of ULF waves using the Lomb-Scargle periodogram technique. The spatial occurrence distribution, frequency characteristics, seasonal effects, solar wind condition, and geomagnetic activity level dependence have been studied. Pc5 wave events were found to dominate at high and polar latitudes with a most probable frequency of 2.08 ± 0.07 mHz, while Pc3-4 waves were relatively more common at midlatitudes on the nightside with a most probable frequency of 11.39 ± 0.14 mHz. At high latitudes, the occurrence rate of Pc4-5 waves maximizes in the dusk sector and during winter. These events tend to occur during low geomagnetic activity and northward interplanetary magnetic field. For the category of radially bounded but longitudinally extended Pc4 events in the duskside ionosphere, an internal driving source is suggested. At midlatitudes, the poloidal Pc3-4 occurrence rate maximizes premidnight and during equinox. This tendency becomes more prominent with increasing auroral electrojet (AE) index and during southward interplanetary magnetic field, which suggests that many of these events are Pi2 and Pc3-4 pulsations associated with magnetotail dynamics during active geomagnetic intervals. The overall occurrence rate of Pc3-5 wave events is lowest in summer, which suggests that the ionospheric conductivity plays a role in controlling ULF wave occurrence.

Switchable multi-wavelength fiber ring laser based on a compact in-fiber Mach-Zehnder interferometer with photonic crystal fiber

NASA Astrophysics Data System (ADS)

Chen, W. G.; Lou, S. Q.; Feng, S. C.; Wang, L. W.; Li, H. L.; Guo, T. Y.; Jian, S. S.

2009-11-01

Switchable multi-wavelength fiber ring laser with an in-fiber Mach-Zehnder interferometer incorporated into the ring cavity serving as wavelength-selective filter at room temperature is demonstrated. The filter is formed by splicing a section of few-mode photonic crystal fiber (PCF) and two segments of single mode fiber (SMF) with the air-holes on the both sides of PCF intentionally collapsed in the vicinity of the splices. By adjusting the states of the polarization controller (PC) appropriately, the laser can be switched among the stable single-, dual- and triple-wavelength lasing operations by exploiting polarization hole burning (PHB) effect.

Switchable dual-wavelength erbium-doped fiber laser based on the photonic crystal fiber loop mirror and chirped fiber Bragg grating

NASA Astrophysics Data System (ADS)

Chen, Wei-Guo; Lou, Shu-Qin; Wang, Li-Wen; Li, Hong-Lei; Guo, Tieying; Jian, Shui-Sheng

2010-03-01

The switchable dual-wavelength erbium-doped fiber laser (EDFL) with a two-mode photonic crystal fiber (PCF) loop mirror and a chirped fiber Bragg grating (CFBG) at room temperature is proposed and experimentally demonstrated. The two-mode PCF loop mirror is formed by inserting a piece of two-mode PCF into a Sagnac loop mirror, with the air-holes of the PCF intentionally collapsing at the splices. By adjusting the state of the polarization controller (PC) appropriately, the laser can be switched between the stable single- and dual-wavelength operations by means of the polarization hole burning (PHB) and spectral hole burning (SHB) effects.

Statistical characteristics of Pc-5 waves at geostationary orbit

NASA Astrophysics Data System (ADS)

Kokubun, S.

The present paper is concerned with an examination of magnetic field data provided by GEOS 2 and 3 satellites. The study has the objecitve to obtain more information regarding the statistical characteristics of Pc5 waves. The data utilized are contained in microfilm plots of the magnetic field observed by the two satellites during the period from 1978 to 1980. Attention is given to ground-satellite correlation of azimuthally-polarized Pc waves, differences in ground-satellite correlations between A-class waves and R-class compressional waves, aspects of delayed Pc5 occurrence, a long-duration Pc5 event lasting for more than three hours, questions of local time dependence of occurrence and frequency, and the relation between compressional Pc5 and magnetospheric substorms.

Optical Polarization as a Probe of the Local Interstellar Medium

NASA Technical Reports Server (NTRS)

Tinbergen, J.

1984-01-01

The use of interstellar polarization as a tool for measuring interstellar dust is discussed. Problems resulting from dust and magnetic field configurations becoming mixed up are discussed, as is the availability of sufficiently bright stars to obtain the photons needed for precision measurements. It is proposed that: (1) on the scale of several hundred parsec, there is a preferential magnetic field direction, as evidenced by observations at the Galactic poles and selected longitudes in the Galactic plane; (2) the local (r 50 pc) region is devoid of dust, as evidenced by the mean square degree of polarization as a function of distance; and, less certainly, that (3) at a distance of less than 5 pc, there is a patch of dust which may be of interest in connection with cloud models.

Pavement cells: a model system for non-transcriptional auxin signalling and crosstalks.

PubMed

Chen, Jisheng; Wang, Fei; Zheng, Shiqin; Xu, Tongda; Yang, Zhenbiao

2015-08-01

Auxin (indole acetic acid) is a multifunctional phytohormone controlling various developmental patterns, morphogenetic processes, and growth behaviours in plants. The transcription-based pathway activated by the nuclear TRANSPORT INHIBITOR RESISTANT 1/auxin-related F-box auxin receptors is well established, but the long-sought molecular mechanisms of non-transcriptional auxin signalling remained enigmatic until very recently. Along with the establishment of the Arabidopsis leaf epidermal pavement cell (PC) as an exciting and amenable model system in the past decade, we began to gain insight into non-transcriptional auxin signalling. The puzzle-piece shape of PCs forms from intercalated or interdigitated cell growth, requiring local intra- and inter-cellular coordination of lobe and indent formation. Precise coordination of this interdigitated pattern requires auxin and an extracellular auxin sensing system that activates plasma membrane-associated Rho GTPases from plants and subsequent downstream events regulating cytoskeletal reorganization and PIN polarization. Apart from auxin, mechanical stress and cytokinin have been shown to affect PC interdigitation, possibly by interacting with auxin signals. This review focuses upon signalling mechanisms for cell polarity formation in PCs, with an emphasis on non-transcriptional auxin signalling in polarized cell expansion and pattern formation and how different auxin pathways interplay with each other and with other signals. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Modulation of auroras by Pc5 pulsations in the dawn sector in association with reappearance of energetic particles at geosynchronous orbit

NASA Astrophysics Data System (ADS)

Saka, O.; Hayashi, K.; Klimushkin, D. Yu.; Mager, P. N.

2014-04-01

Geomagnetic Pc5 pulsations were observed in the dawn sector of the auroral zone on 17 January 1994 in association with increased energetic ion fluxes at geosynchronous orbit 10 min after the Pi2 onset. The characteristic properties of auroras associated with these pulsations were studied using movies taken by an all-sky imager. It was found that a pulsating aurora (PA) can be an optical manifestation of the Pc5 waves by a strong poloidal component observed with ground-based magnetometers. Goes7 observations showed compressional pulsations with the same period which can be attributed to the influence of the finite pressure of plasma and field line curvature on the poloidally polarized Alfvén waves. These poloidal pulsations may be generated by the ion injection observed with the LANL 1989-046 satellite. Two auroral arcs were observed north of the PA with optical features characteristic for the toroidal field line resonances: strong localization across L-shells, 180° phase change across the resonance, poleward phase propagation. Thus the Pc5 oscillations split into the toroidal and poloidal mode and oscillated coherently at latitudes from 62°N to 70°N. This study provides observational evidence of polarization splitting of the Alfven oscillation spectrum. Such a polarization splitting would occur in association with the reappearance of the energetic particles at geosynchronous orbit.

Dendritic copper phthalocyanine with aggregation induced blue emission and solid-state fluorescence

NASA Astrophysics Data System (ADS)

Wang, Jiayi; Pan, Lin; Zhou, Xuefei; Jia, Kun; Liu, Xiaobo

2016-09-01

In this work, dendritic copper phthalocyanine (CuPc) showing obvious aggregation induced emission (AIE) and strong solid-state fluorescence was synthesized. It was found that synthesized CuPc can be easily solubilized in polar aprotic solvent, where no fluorescence signal was detected. Interestingly, both the CuPc aggregates in solution and solid-state powder exhibited strong fluorescence emission around 480 nm, which should be attributed to the restriction of intramolecular rotation as rationalized in aggregation induced emission framework. Meanwhile the obvious crystalline enhanced solid-state fluorescent emission is observed for CuPc powder.

Effects of symmetry and spin configuration on spin-dependent transport properties of iron-phthalocyanine-based devices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cui, Li-Ling; School of Science, Hunan University of Technology, Zhuzhou 412007; Yang, Bing-Chu, E-mail: bingchuyang@csu.edu.cn

2014-07-21

Spin-dependent transport properties of nanodevices constructed by iron-phthalocyanine (FePc) molecule sandwiched between two zigzag graphene nanoribbon electrodes are studied using first-principles quantum transport calculations. The effects of the symmetry and spin configuration of electrodes have been taken into account. It is found that large magnetoresistance, large spin polarization, dual spin-filtering, and negative differential resistance (NDR) can coexist in these devices. Our results show that 5Z-FePc system presents well conductive ability in both parallel (P) and anti-parallel (AP) configurations. For 6Z-FePc-P system, spin filtering effect and large spin polarization can be found. A dual spin filtering and NDR can also bemore » shown in 6Z-FePc-AP. Our studies indicate that the dual spin filtering effect depends on the orbitals symmetry of the energy bands and spin mismatching of the electrodes. And all the effects would open up possibilities for their applications in spin-valve, spin-filter as well as effective spin diode devices.« less

Simple and advanced ferromagnet/molecule spinterfaces

NASA Astrophysics Data System (ADS)

Gruber, M.; Ibrahim, F.; Djedhloul, F.; Barraud, C.; Garreau, G.; Boukari, S.; Isshiki, H.; Joly, L.; Urbain, E.; Peter, M.; Studniarek, M.; Da Costa, V.; Jabbar, H.; Bulou, H.; Davesne, V.; Halisdemir, U.; Chen, J.; Xenioti, D.; Arabski, J.; Bouzehouane, K.; Deranlot, C.; Fusil, S.; Otero, E.; Choueikani, F.; Chen, K.; Ohresser, P.; Bertran, F.; Le Fèvre, P.; Taleb-Ibrahimi, A.; Wulfhekel, W.; Hajjar-Garreau, S.; Wetzel, P.; Seneor, P.; Mattana, R.; Petroff, F.; Scheurer, F.; Weber, W.; Alouani, M.; Beaurepaire, E.; Bowen, M.

2016-10-01

Spin-polarized charge transfer between a ferromagnet and a molecule can promote molecular ferromagnetism 1, 2 and hybridized interfacial states3, 4. Observations of high spin-polarization of Fermi level states at room temperature5 designate such interfaces as a very promising candidate toward achieving a highly spin-polarized, nanoscale current source at room temperature, when compared to other solutions such as half-metallic systems and solid-state tunnelling over the past decades. We will discuss three aspects of this research. 1) Does the ferromagnet/molecule interface, also called an organic spinterface, exhibit this high spin-polarization as a generic feature? Spin-polarized photoemission experiments reveal that a high spin-polarization of electronics states at the Fermi level also exist at the simple interface between ferromagnetic cobalt and amorphous carbon6. Furthermore, this effect is general to an array of ferromagnetic and molecular candidates7. 2) Integrating molecules with intrinsic properties (e.g. spin crossover molecules) into a spinterface toward enhanced functionality requires lowering the charge transfer onto the molecule8 while magnetizing it1,2. We propose to achieve this by utilizing interlayer exchange coupling within a more advanced organic spinterface architecture. We present results at room temperature across the fcc Co(001)/Cu/manganese phthalocyanine (MnPc) system9. 3) Finally, we discuss how the Co/MnPc spinterface's ferromagnetism stabilizes antiferromagnetic ordering at room temperature onto subsequent molecules away from the spinterface, which in turn can exchange bias the Co layer at low temperature10. Consequences include tunnelling anisotropic magnetoresistance across a CoPc tunnel barrier11. This augurs new possibilities to transmit spin information across organic semiconductors using spin flip excitations12.

Analysis of field-aligned structure of compressional Pc 5 waves and associated energetic ion modulations observed by Polar at L~9.5

NASA Astrophysics Data System (ADS)

Capman, E.; Engebretson, M. J.; Pilipenko, V.; Russell, C. T.; Peterson, W. K.

2012-12-01

Nearly all previous studies of storm-time compressional Pc 5 waves have used data from low-inclination satellites, so the field-aligned structure of these waves could be determined only statistically or by inference. However, the high inclination of the Polar satellite's orbit allowed it to approximately follow a flux tube across the equator. In this study we present examples of compressional Pc 5 events identified during Polar's 2001-02 and 2002-03 duskside passages. The focus of this presentation is on exploring the field-aligned structure of the observed waves near the geomagnetic equator. At least two frequencies were identified in each event. In many cases these are a 1st (fundamental) harmonic with a node in the field-aligned (Bz) component near the geomagnetic equator, and a 2nd harmonic with an anti-node near the equator. To verify this assumption we applied the analytical signal method, verified by manual hodogram analysis, to monitor the amplitude and phase variations of the radial (Bx) and compressional (Bz) components at certain frequencies. The following transitions occurred near the time when Polar crossed the geomagnetic equator: The phase difference was 0° in the southern hemisphere and then 180° out of phase in the northern hemisphere. The waves were often linearly polarized, and the inclination angle of the polarization ellipse in the Bx-Bz plane was negative in the southern hemisphere and positive in the northern hemisphere. The ellipticity still had a slight positive bias in the southern hemisphere and a slight negative bias in the northern hemisphere. These observational results are compared with the results of modeling of coupled MHD Alfven and slow magnetosonic modes.

Pulsar Polar Cap Heating and Surface Thermal X-ray Emission. 1; Curvature Radiation Pair Fronts

NASA Technical Reports Server (NTRS)

Harding, Alice K.; Muslimov, Alexander G.; White, Nicholas E. (Technical Monitor)

2002-01-01

We investigate the effect of pulsar polar cap (PC) heating produced by positrons returning from the upper pair formation front. Our calculations are based on a self-consistent treatment of the pair dynamics and the effect of electric field screening by the returning positrons. We calculate the resultant X-ray luminosities and discuss the dependence of the PC heating efficiencies on pulsar parameters, such as characteristic spin-down age, spin period, and surface magnetic field strength. In this study we concentrate on the regime where the pairs are produced in a magnetic field by curvature photons emitted by accelerating electrons. Our theoretical results are not in conflict with the available observational x-ray data and suggest that the effect of PC heating should significantly contribute to the thermal x-ray fluxes from middle-aged and old pulsars. The implications for current and future x-ray observations of pulsars are briefly outlined.

Polarization-resolved second-harmonic generation microscopy as a method to visualize protein-crystal domains

PubMed Central

DeWalt, Emma L.; Begue, Victoria J.; Ronau, Judith A.; Sullivan, Shane Z.; Das, Chittaranjan; Simpson, Garth J.

2013-01-01

Polarization-resolved second-harmonic generation (PR-SHG) microscopy is described and applied to identify the presence of multiple crystallographic domains within protein-crystal conglomerates, which was confirmed by synchrotron X-ray diffraction. Principal component analysis (PCA) of PR-SHG images resulted in principal component 2 (PC2) images with areas of contrasting negative and positive values for conglomerated crystals and PC2 images exhibiting uniformly positive or uniformly negative values for single crystals. Qualitative assessment of PC2 images allowed the identification of domains of different internal ordering within protein-crystal samples as well as differentiation between multi-domain conglomerated crystals and single crystals. PR-SHG assessments of crystalline domains were in good agreement with spatially resolved synchrotron X-ray diffraction measurements. These results have implications for improving the productive throughput of protein structure determination through early identification of multi-domain crystals. PMID:23275165

Fluorescence polarization-based assay using N-glycan-conjugated quantum dots for screening in hemagglutinin blockers for influenza A viruses.

PubMed

Okamatsu, Masatoshi; Feng, Fei; Ohyanagi, Tatsuya; Nagahori, Noriko; Someya, Kazuhiko; Sakoda, Yoshihiro; Miura, Nobuaki; Nishimura, Shin-Ichiro; Kida, Hiroshi

2013-02-01

Attachment of influenza virus to susceptible cells is mediated by viral protein hemagglutinin (HA), which recognizes cell surface glycoconjugates that terminate in α-sialosides. To develop anti-influenza drugs based on inhibition of HA-mediated infection, novel fluorescent nanoparticles displaying multiple biantennary N-glycan chains with α-sialosides (A2-PC-QDs) that have high affinity for the HA were designed and constructed. The A2-PC-QDs enabled an easy and efficient fluorescence polarization (FP) assay for detection of interaction with the HA and competitive inhibition even by small molecule compounds against A2-PC-QDs-HA binding. The quantum dot (QD)-based FP assay established in the present study is a useful tool for high-throughput screening and to accelerate the development of novel and more effective blockers of the viral attachment of influenza virus. Copyright © 2012 Elsevier B.V. All rights reserved.

Enhanced dielectric properties due to space charge-induced interfacial polarization in multilayer polymer films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Xinyue; Tseng, Jung-Kai; Treufeld, Imre

We report that with the recent advancement of power electronics, polymer film capacitors have become increasingly important. However, the low temperature rating (up to 85 °C) and low energy density (5 J cm -3 at breakdown) of state-of-the-art biaxially oriented polypropylene (BOPP) films have been limiting factors for advanced power electronics. Based on our recent work, multilayer films (MLFs), which consist of a high energy density polymer [e.g., poly(vinylidene fluoride) (PVDF)] and a high breakdown/low loss polymer [e.g., polycarbonate (PC)], have shown potential to achieve high energy density (13–17 J cm -3), enhanced breakdown strength, high temperature tolerance, and lowmore » loss simultaneously. In this study, the dielectric properties of PC/PVDF 50/50 32- and 256-layer (32L and 256L) films were investigated. The breakdown strength of the 32L film was as high as 800 MV m -1 at room temperature, as compared to 600 MV m -1 of PVDF and 750 MV m-1 of PC. The temperature rating of the 32L film reached 120 °C, higher than that of BOPP. In addition, it was observed that the 32L film with thicker PC layers exhibited a higher breakdown strength and a lower DC conductivity than the 256L film with thinner PC layers at elevated temperatures. These differences were attributed to the difference in the interfacial polarization of space charges, which was further verified by thermally stimulated depolarization current spectroscopy. In conclusion, we conclude that interfacial polarization endows MLFs with the desirable dielectric properties for next generation film capacitors.« less

Enhanced dielectric properties due to space charge-induced interfacial polarization in multilayer polymer films

DOE PAGES

Chen, Xinyue; Tseng, Jung-Kai; Treufeld, Imre; ...

2017-09-15

We report that with the recent advancement of power electronics, polymer film capacitors have become increasingly important. However, the low temperature rating (up to 85 °C) and low energy density (5 J cm -3 at breakdown) of state-of-the-art biaxially oriented polypropylene (BOPP) films have been limiting factors for advanced power electronics. Based on our recent work, multilayer films (MLFs), which consist of a high energy density polymer [e.g., poly(vinylidene fluoride) (PVDF)] and a high breakdown/low loss polymer [e.g., polycarbonate (PC)], have shown potential to achieve high energy density (13–17 J cm -3), enhanced breakdown strength, high temperature tolerance, and lowmore » loss simultaneously. In this study, the dielectric properties of PC/PVDF 50/50 32- and 256-layer (32L and 256L) films were investigated. The breakdown strength of the 32L film was as high as 800 MV m -1 at room temperature, as compared to 600 MV m -1 of PVDF and 750 MV m-1 of PC. The temperature rating of the 32L film reached 120 °C, higher than that of BOPP. In addition, it was observed that the 32L film with thicker PC layers exhibited a higher breakdown strength and a lower DC conductivity than the 256L film with thinner PC layers at elevated temperatures. These differences were attributed to the difference in the interfacial polarization of space charges, which was further verified by thermally stimulated depolarization current spectroscopy. In conclusion, we conclude that interfacial polarization endows MLFs with the desirable dielectric properties for next generation film capacitors.« less

Disparate effects of oxidation on plasma acyltransferase activities: inhibition of cholesterol esterification but stimulation of transesterification of oxidized phospholipids.

PubMed

Subbaiah, P V; Liu, M

1996-05-31

Oxidation of lipoproteins results in the formation of several polar phospholipids with pro-inflammatory and pro-atherogenic properties. To examine the possible role of lecithin/cholesterol acyltransferase (LCAT) in the metabolism of these oxidized phospholipids, we oxidized whole plasma with either Cu(2+) or a free-radical generator, and determined the various activities of LCAT. Oxidation caused a reduction in plasma phosphatidylcholine (PC), an increase in a short-chain polar PC (SCP-PC), and an inhibition of the transfer of long-chain acyl groups to cholesterol (LCAT activity) or to lyso PC (lysolecithin acyltransferase (LAT) I activity). However, the transfer of short-chain acyl groups from SCP-PC to lyso PCLAT II activity) was stimulated several fold, in direct correlation with the degree of oxidation. LAT II activity was not stimulated by oxidation in LCAT-deficient plasma, showing that it is carried out by LCAT. Oxidized normal plasma exhibited low LCAT activity even in the presence of exogenous proteoliposome substrate, indicating that the depletion of substrate PC was not responsible for the loss of activity. Oxidation of isolated LDL or HDL abolished their ability to support LCAT and LAT I activities of exogenous enzyme, but promoted the LAT II activity. Purified LCAT lost its LCAT and LAT I functions, but not its LAT II function, when oxidized in vitro. These results show that while oxidation of plasma causes a loss of LCAT's ability to transfer long-chain acyl groups, its ability to transfer short-chain acyl groups, from SCP-PC is retained, and even stimulated, suggesting that LCAT may have a physiological role in the metabolism of oxidized PC in plasma.

Polycystin-1 Surface Localization Is Stimulated by Polycystin-2 and Cleavage at the G Protein-coupled Receptor Proteolytic Site

PubMed Central

Chapin, Hannah C.; Rajendran, Vanathy

2010-01-01

Polycystin (PC)1 and PC2 are membrane proteins implicated in autosomal dominant polycystic kidney disease. A physiologically relevant cleavage at PC1's G protein-coupled receptor proteolytic site (GPS) occurs early in the secretory pathway. Our results suggest that PC2 increases both PC1 GPS cleavage and PC1's appearance at the plasma membrane. Mutations that prevent PC1's GPS cleavage prevent its plasma membrane localization. PC2 is a member of the trp family of cation channels and is an important PC1 binding partner. The effect of PC2 on PC1 localization is independent of PC2 channel activity, as tested using channel-inhibiting PC2 mutations. PC1 and PC2 can interact through their C-terminal tails, but removing the C-terminal tail of either protein has no effect on PC1 surface localization in human embryonic kidney 293 cells. Experiments in polarized LLC-PK cells show that apical and ciliary PC1 localization requires PC2 and that this delivery is sensitive to PC2 truncation. In sum, our work shows that PC2 expression is required for the movement of PC1 to the plasma and ciliary membranes. In fibroblast cells this localization effect is independent of PC2's channel activity or PC1 binding ability but involves a stimulation of PC1's GPS cleavage before the PC1 protein's surface delivery. PMID:20980620

Compact Mach-Zehnder interferometer based on photonic crystal fiber and its application in switchable multi-wavelength fiber laser

NASA Astrophysics Data System (ADS)

Chen, Weiguo; Lou, Shuqin; Wang, Liwen; Li, Honglei; Guo, Tieying; Jian, Shuisheng

2009-08-01

The compact Mach-Zehnder interferometer is proposed by splicing a section of photonic crystal fiber (PCF) and two pieces of single mode fiber (SMF) with the air-holes of PCF intentionally collapsed in the vicinity of the splices. The depedence of the fringe spacing on the length of PCF is investigated. Based on the Mach-Zehnder interferometer as wavelength-selective filter, a switchable dual-wavelength fiber ring laser is demonstrated with a homemade erbiumdoped fiber amplifier (EDFA) as the gain medium at room temperature. By adjusting the states of the polarization controller (PC) appropriately, the laser can be switched among the stable single-and dual -wavelength lasing operations by exploiting polarization hole burning (PHB) effect.

Comparative Study of Different Polar Groups of EPA-Enriched Phospholipids on Ameliorating Memory Loss and Cognitive Deficiency in Aged SAMP8 Mice.

PubMed

Zhou, Miao-Miao; Che, Hong-Xia; Huang, Jia-Qi; Zhang, Tian-Tian; Xu, Jie; Xue, Chang-Hu; Wang, Yu-Ming

2018-04-01

Recent studies have shown that omega-3 PUFAs enriched phospholipids (n-3 PUFA-PLs) have beneficial effects on memory and cognition. However, most reports only attribute the benefit to docosahexaenoic acid (DHA) and pay little attention to eicosapentaenoic acid (EPA). We investigate the effect of EPA-enriched phospholipids on cognitive deficiency in senescence-accelerated prone 8 (SAMP8) mouse. Ten-month-old SAMP8 mice are fed with 2% (w/w) EPA-enriched phosphatidylcholine/phosphatidyl ethanolamine (EPA-PC/PE; EPA:DHA = 46.8:3.01) or 2% EPA-enriched phosphatidylserine (EPA-PS; biosynthesized from EPA-PC/PE) for 8 weeks; we then test the behavioral performances in the Barnes maze test and Morris maze test; the changes of oxidative stress, apoptosis, neurotrophic factors, tau phosphorylation, and Aβ pathology are also measured. The results of behavior tests indicate that both EPA-PC/PE and EPA-PS significantly improve memory and cognitive deficiency. It is found that remarkable amelioration of oxidative stress and apoptosis occurs in both EPA-PC/PE and EPA-PS groups. EPA-PS shows more ameliorative effects than EPA-PC/PE on neurotrophic activity by decreasing hyper-phosphorylation of tau and depressing the generation and accumulation of β-amyloid peptide (Aβ). These data suggest that EPA-PS exhibits better effects than EPA-PC/PE on ameliorating memory and cognitive function, which might be attributed to the phospholipid polar groups. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dynamics and Synchronization of Nonlinear Oscillators with Time Delays: A Study with Fiber Lasers

DTIC Science & Technology

2007-07-19

or coupling lines PC Polarization Controller PD Photodetector VA Variable Attenuator WDM Wavelength Division Multiplexer x Chapter 1 Introduction 1.1...lasers and detectors. Injection locking of lasers is a common practice that can be used to lock the frequency and phase of a laser to an injected signal...finding a basis vector that maximizes the mean squared projection of the data. Succeeding basis vectors are found that max- imize the projection with the

Pulsar Pair Cascades in Magnetic Fields with Offset Polar Caps

NASA Technical Reports Server (NTRS)

Harding, Alice K.; Muslimov, Alex G.

2012-01-01

Neutron star magnetic fields may have polar caps (PC) that are offset from the dipole axis, through field-line sweepback near the light cylinder or non-symmetric currents within the star. The effects of such offsets on electron-positron pair cascades are investigated, using simple models of dipole magnetic fields with small distortions that shift the PCs by different amounts or directions. Using a Monte Carlo pair cascade simulation, we explore the changes in the pair spectrum, multiplicity and energy flux across the PC, as well as the trends in pair flux and pair energy flux with spin-down luminosity, L(sub sd). We also give an estimate of the distribution of heating flux from returning positrons on the PC for different offsets. We find that even modest offsets can produce significant increases in pair multiplicity, especially for pulsars that are near or beyond the pair death lines for centered PCs, primarily because of higher accelerating fields. Pair spectra cover several decades in energy, with the spectral range of millisecond pulsars (MSPs) two orders of magnitude higher than for normal pulsars, and PC offsets allow significant extension of all spectra to lower pair energies. We find that the total PC pair luminosity L(sub pair) is proportional to L(sub sd), with L(sub pair) approximates 10(exp -3) L(sub sd) for normal pulsars and L(sub pair) approximates 10(exp -2) L(sub sd) for MSPs. Remarkably, the total PC heating luminosity for even large offsets increases by less than a factor of two, even though the PC area increases by much larger factors, because most of the heating occurs near the magnetic axis.

Humidity and illumination organic semiconductor copper phthalocyanine sensor for environmental monitoring.

PubMed

Karimov, K S; Qazi, I; Khan, T A; Draper, P H; Khalid, F A; Mahroof-Tahir, M

2008-06-01

In this investigation properties of organic semiconductor copper phthalocyanine (CuPc) capacitive humidity and illumination sensors were studied. Organic thin film was deposited by vacuum evaporation on a glass substrate with silver surface-type electrodes to form the Ag/CuPc/Ag sensor. The capacitance of the samples was evaluated at room temperature in the relative humidity range of 35-92%. It was observed that capacitance of the Ag/CuPc/Ag sensor increases with increase in humidity. The ratio of the relative capacitance to relative humidity was about 200. It is assumed that in general the capacitive response of the sensor is associated with polarization due to absorption of water molecules and transfer of charges (electrons and holes). It was observed that under filament lamp illumination of up to 1,000 lx the capacitance of the Ag/CuPc/Ag photo capacitive detectors increased continuously by 20% as compared to dark condition. It is assumed that photo capacitive response of the sensor is associated with polarization due to transfer of photo-generated electrons and holes. An equivalent circuit of the Ag/CuPc/Ag capacitive humidity and illumination sensor was developed. Humidity and illumination dependent capacitance properties of this sensor make it attractive for use in humidity and illumination multi-meters. The sensor may be used in instruments for environmental monitoring of humidity and illumination.

A 100 mW-level single-mode switchable dual-wavelength erbium-doped fiber laser

NASA Astrophysics Data System (ADS)

Cheng, Jianqun; Zhang, Liaolin; Sharafudeen, Kaniyarakkal; Qiu, Jianrong

2013-10-01

A switchable dual-wavelength CW erbium-doped fiber laser with two cascaded fiber Bragg gratings has been proposed and demonstrated experimentally at room temperature. The laser uses a linear resonant cavity configuration incorporating a Sagnac loop with a polarization controller (PC) and can switch flexibly to output a single wavelength or dual wavelengths based on the polarization hole burning (PHB) effect. The slope efficiency and maximum output power can reach 23% and 96 mW, respectively. The two lasing peaks of the laser, with a narrow linewidth output and an optical signal-to-noise ratio of more than 50 dB, are located in the C and L bands of the optical communication window, respectively. The laser shows good stability with respect to the wavelength and output power.

Lipid composition and emulsifying properties of canola lecithin from enzymatic degumming.

PubMed

Xie, Meizhen; Dunford, Nurhan Turgut

2017-03-01

This study investigated the polar lipid composition and emulsifying properties of canola lecithin from enzymatic degumming (CLED). Phospholipase A 1 was used for enzymatic degumming of crude canola oil to collect lecithin sample. Canola lecithin from water degumming (CLWD) was also collected and served as the control. The results showed that the contents of phosphatidylethanolamine (PE) (2.99%) and phosphatidylcholine (PC) (6.59%) in CLED were significantly lower than that in CLWD (PE 15.55% and PC 21.93%); while the content of lysophosphatidylcholine (LPC) (19.45%) in CLED was significantly higher than that in CLWD (3.27%). Unsaturated fatty acids accounted for a higher percentage of the total fatty acids in CLED than in CLWD. CLED promoted more stable o/w emulsions than CLWD. This study provides a better understanding of the chemical nature of CLED, and important information for utilization of CLED as o/w emulsifier. Copyright © 2016 Elsevier Ltd. All rights reserved.

PC index as a proxy of the solar wind energy that entered into the magnetosphere: 2. Relation to the interplanetary electric field E KL before substorm onset

NASA Astrophysics Data System (ADS)

Troshichev, O. A.; Sormakov, D. A.

2015-10-01

This paper (the second of a series) presents the results of statistical investigation of relationship between the interplanetary electric field E KL and the Polar Cap (PC) index in case of magnetic substorms (1998-2001), which have been analyzed in Troshichev et al. (J. Geophys. Res. Space Physics, 119, 2014). The PC index is directly related to the E KL field variations on interval preceding the substorm sudden onset (SO): correlation R > 0.5 is typical of more than 90 % of isolated substorms, 80 % of expanded substorms, and 99 % of events with coordinated E KL and PC jumps. The low or negative correlation observing in ~10 % of examined substorms suggests that the solar wind flow measured by the Advanced Composition Explorer (ACE) spacecraft in the Lagrange point L1 did not encounter the magnetosphere in these cases. Examination of the delay times Δ T in the response of PC index to E KL variations provides the following results: (1) delay times do not depend on separate solar wind parameters, such as solar wind speed V X and interplanetary magnetic field (IMF) B Z component, contrary to general conviction, (2) the Δ T value is best controlled by the E KL field growth rate (d E KL/dt), (3) the lower Δ T limit (5-7 min is attained under conditions of the higher E KL growth rate, and (4) the PC index provides the possibility to verify the solar wind flow transportation time from ACE position (where the solar wind speed is estimated) to magnetosphere. These results, in combination with data testifying that the substorm onsets are related to the PC precursors, demonstrate that the PC index is an adequate ground-based indicator of the solar wind energy incoming into the magnetosphere.

Planck intermediate results: XXXVIII. E- and B-modes of dust polarization from the magnetized filamentary structure of the interstellar medium

DOE PAGES

Ade, P. A. R.; Aghanim, N.; Arnaud, M.; ...

2016-02-09

The quest for a B-mode imprint from primordial gravity waves on the polarization of the cosmic microwave background (CMB) requires the characterization of foreground polarization from Galactic dust. In this paper, we present a statistical study of the filamentary structure of the 353 GHz Planck Stokes maps at high Galactic latitude, relevant to the study of dust emission as a polarized foreground to the CMB. We filter the intensity and polarization maps to isolate filaments in the range of angular scales where the power asymmetry between E-modes and B-modes is observed. Using the Smoothed Hessian Major Axis Filament Finder (SMAFF),more » we identify 259 filaments at high Galactic latitude, with lengths larger or equal to 2° (corresponding to 3.5 pc in length for a typical distance of 100 pc). Thesefilaments show a preferred orientation parallel to the magnetic field projected onto the plane of the sky, derived from their polarization angles. We present mean maps of the filaments in Stokes I, Q, U, E, and B, computed by stacking individual images rotated to align the orientations of the filaments. Combining the stacked images and the histogram of relative orientations, we estimate the mean polarization fraction of the filaments to be 11%. Furthermore, we show that the correlation between the filaments and the magnetic field orientations may account for the E and B asymmetry and the C ℓ TE/C ℓ EE ratio, reported in the power spectra analysis of the Planck353 GHz polarization maps. Finally, future models of the dust foreground for CMB polarization studies will need to take into account the observed correlation between the dust polarization and the structure of interstellar matter.« less

New observations, new theoretical results and controversies regarding PC 3-5 waves

NASA Astrophysics Data System (ADS)

Takahashi, K.

Observations and theories of medium- to long-period (Pc 3-5) magnetic pulsations excited by magnetospheric particles are described. Satellite observations indicate that most pulsations can be classified into two groups according to their magnetic field polarization. One group has a transverse magnetic perturbation and the other strongly compressional perturbation. Despite this difference in polarization they share common characteristics, including large azimuthal wave number, westward propagation, and antisymmetric field-aligned structure. Recent theories describe these observations in a unified framework. It has been pointed out that trapped energetic ions play an important role in determining the instability threshold and the mode structure of the pulsations. Observations and theories of energetic particle response to the excited pulsations are also described.

Stable dual-wavelength single-longitudinal-mode ring erbium-doped fiber laser for optical generation of microwave frequency

NASA Astrophysics Data System (ADS)

Wang, T.; Liang, G.; Miao, X.; Zhou, X.; Li, Q.

2012-05-01

We demonstrate a simple dual-wavelength ring erbium-doped fiber laser operating in single-longitudinal-mode (SLM) at room temperature. A pair of reflection type short-period fiber Bragg gratings (FBGs), which have two different center wavelengths of 1545.072 and 1545.284 nm, are used as the wavelength-selective component of the laser. A segment of unpumped polarization maintaining erbium-doped fiber (PM-EDF) is acted as a narrow multiband filter. By turning the polarization controller (PC) to enhance the polarization hole burning (PHB), the single-wavelength and dual-wavelength laser oscillations are observed at 1545.072 and 1545.284 nm. The output power variation is less than 0.6 dB for both wavelengths over a five-minute period and the optical signal to noise ratio (OSNR) is greater than 50 dB. By beating the dual-wavelengths at a photodetector (PD), a microwave signal at 26.44 GHz is demonstrated.

Polycystin-1 binds Par3/aPKC and controls convergent extension during renal tubular morphogenesis

NASA Astrophysics Data System (ADS)

Castelli, Maddalena; Boca, Manila; Chiaravalli, Marco; Ramalingam, Harini; Rowe, Isaline; Distefano, Gianfranco; Carroll, Thomas; Boletta, Alessandra

2013-10-01

Several organs, including the lungs and kidneys, are formed by epithelial tubes whose proper morphogenesis ensures correct function. This is best exemplified by the kidney, where defective establishment or maintenance of tubular diameter results in polycystic kidney disease, a common genetic disorder. Most polycystic kidney disease cases result from loss-of-function mutations in the PKD1 gene, encoding Polycystin-1, a large receptor of unknown function. Here we demonstrate that PC-1 has an essential role in the establishment of correct tubular diameter during nephron development. Polycystin-1 associates with Par3 favouring the assembly of a pro-polarizing Par3/aPKC complex and it regulates a programme of cell polarity important for oriented cell migration and for a convergent extension-like process during tubular morphogenesis. Par3 inactivation in the developing kidney results in defective convergent extension and tubular morphogenesis, and in renal cyst formation. Our data define Polycystin-1 as central to cell polarization and to epithelial tube morphogenesis and homeostasis.

Distributed polar-coded OFDM based on Plotkin's construction for half duplex wireless communication

NASA Astrophysics Data System (ADS)

Umar, Rahim; Yang, Fengfan; Mughal, Shoaib; Xu, HongJun

2018-07-01

A Plotkin-based polar-coded orthogonal frequency division multiplexing (P-PC-OFDM) scheme is proposed and its bit error rate (BER) performance over additive white gaussian noise (AWGN), frequency selective Rayleigh, Rician and Nakagami-m fading channels has been evaluated. The considered Plotkin's construction possesses a parallel split in its structure, which motivated us to extend the proposed P-PC-OFDM scheme in a coded cooperative scenario. As the relay's effective collaboration has always been pivotal in the design of cooperative communication therefore, an efficient selection criterion for choosing the information bits has been inculcated at the relay node. To assess the BER performance of the proposed cooperative scheme, we have also upgraded conventional polar-coded cooperative scheme in the context of OFDM as an appropriate bench marker. The Monte Carlo simulated results revealed that the proposed Plotkin-based polar-coded cooperative OFDM scheme convincingly outperforms the conventional polar-coded cooperative OFDM scheme by 0.5 0.6 dBs over AWGN channel. This prominent gain in BER performance is made possible due to the bit-selection criteria and the joint successive cancellation decoding adopted at the relay and the destination nodes, respectively. Furthermore, the proposed coded cooperative schemes outperform their corresponding non-cooperative schemes by a gain of 1 dB under an identical condition.

Phthalocyanine-labeled LDL for tumor imaging and photodynamic therapy

NASA Astrophysics Data System (ADS)

Li, Hui; Marotta, Diane; Kim, Soungkyoo; Chance, Britton; Glickson, Jerry D.; Busch, Theresa M.; Zheng, Gang

2005-01-01

Current limitation of both near-infrared (NIR) tumor imaging and photodynamic therapy (PDT) is their lack of sufficient tumor-to-tissue contrast due to the relatively non-specific nature of delivering dye to the tumor, which has led to false negatives for NIR imaging and inadequate therapeutic ratio for PDT. Hence, agents targeting "cancer signatures", i.e. molecules that accumulate selectively in cancer cells, are particular attractive. One of these signatures is low-density-lipoprotein receptor (LDLR), which is overexpressed in many tumors. We have developed pyropheophorbide cholesterol oleate reconstituted LDL as a LDLR-targeting photosensitizer (PS) and demonstrated its LDLR-mediated uptake in vitro and in vivo. To improve the labeling efficiency for achieving high probe/protein ratio, tetra-t-butyl silicon phthalocyanine bearing two oleate moieties at its axial positions, (tBu)4SiPcBOA, was designed and synthesized. This compound was designed to 1) prevent the PS aggregation; 2) improve the PS solubility in non-polar solvent; and 3) maximize the PS binding to LDL phospholipid monolayer. Using this novel strategy, (tBu)4SiPcBOA was reconstituted into LDL (r-SiPcBOA-LDL) with a very high payload (500:1 molar ratio). In addition, (tBu)4SiPcBOA reconstituted acetylated LDL (r-SiPcBOA)-AcLDL with similar payload was also prepared. Since Ac-LDL cannot bind to LDLR, (r-SiPcBOA)-AcLDL can serve as the negative control to evaluate LDLR targeting specificity. For biological evaluation of these new agents, confocal microscopy and in vitro PDT protocols were performed using LDLR-overexpressing human hepatoblastoma G2 (HepG2) tumor model. These studies suggest that LDL serves as a delivery vehicle to bring large amount of the NIR/PDT agents selectively to tumor cells overexpressing LDLR.

Exciplex mediated photoinduced electron transfer reactions of phthalocyanine-fullerene dyads.

PubMed

Niemi, Marja; Tkachenko, Nikolai V; Efimov, Alexander; Lehtivuori, Heli; Ohkubo, Kei; Fukuzumi, Shunichi; Lemmetyinen, Helge

2008-07-31

Evidences of an intramolecular exciplex intermediate in a photoinduced electron transfer (ET) reaction of double-linked free-base and zinc phthalocyanine-C60 dyads were found. This was the first time for a dyad with phthalocyanine donor. Excitation of the phthalocyanine moiety of the dyads results in rapid ET from phthalocyanine to fullerene via an exciplex state in both polar and nonpolar solvents. Relaxation of the charge-separated (CS) state Pc(*+)-C60(*-) in a polar solvent occurs directly to the ground state in 30-70 ps. In a nonpolar solvent, roughly 20% of the molecules undergo transition from the CS state to phthalocyanine triplet state (3)Pc*-C60 before relaxation to the ground state. Formation of the CS state was confirmed with electron spin resonance measurements at low temperature in both polar and nonpolar solvent. Reaction schemes for the photoinduced ET reactions of the dyads were completed with rate constants obtained from the time-resolved absorption and emission measurements and with state energies obtained from the fluorescence, phosphorescence, and voltammetric measurements.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ade, P. A. R.; Aghanim, N.; Arnaud, M.

The quest for a B-mode imprint from primordial gravity waves on the polarization of the cosmic microwave background (CMB) requires the characterization of foreground polarization from Galactic dust. In this paper, we present a statistical study of the filamentary structure of the 353 GHz Planck Stokes maps at high Galactic latitude, relevant to the study of dust emission as a polarized foreground to the CMB. We filter the intensity and polarization maps to isolate filaments in the range of angular scales where the power asymmetry between E-modes and B-modes is observed. Using the Smoothed Hessian Major Axis Filament Finder (SMAFF),more » we identify 259 filaments at high Galactic latitude, with lengths larger or equal to 2° (corresponding to 3.5 pc in length for a typical distance of 100 pc). Thesefilaments show a preferred orientation parallel to the magnetic field projected onto the plane of the sky, derived from their polarization angles. We present mean maps of the filaments in Stokes I, Q, U, E, and B, computed by stacking individual images rotated to align the orientations of the filaments. Combining the stacked images and the histogram of relative orientations, we estimate the mean polarization fraction of the filaments to be 11%. Furthermore, we show that the correlation between the filaments and the magnetic field orientations may account for the E and B asymmetry and the C ℓ TE/C ℓ EE ratio, reported in the power spectra analysis of the Planck353 GHz polarization maps. Finally, future models of the dust foreground for CMB polarization studies will need to take into account the observed correlation between the dust polarization and the structure of interstellar matter.« less

Intestinal absorption of miltefosine: contribution of passive paracellular transport.

PubMed

Ménez, Cécile; Buyse, Marion; Dugave, Christophe; Farinotti, Robert; Barratt, Gillian

2007-03-01

This study aimed to characterize the transepithelial transport of miltefosine (HePC), the first orally effective drug against visceral leishmaniasis, across the intestinal barrier to further understand its oral absorption mechanism. Caco-2 cell monolayers were used as an in vitro model of the human intestinal barrier. The roles of active and passive mechanisms in HePC intestinal transport were investigated and the relative contributions of the transcellular and paracellular routes were estimated. HePC transport was observed to be pH-independent, partially temperature-dependent, linear as a function of time and non-saturable as a function of concentration. The magnitude of HePC transport was quite similar to that of the paracellular marker mannitol, and EDTA treatment led to an increase in HePC transport. Furthermore, HePC transport was found to be similar in the apical-to-basolateral and basolateral-to-apical directions, strongly suggesting that HePC exhibits non-polarized transport and that no MDR-mediated efflux was involved. These results demonstrate that HePC crosses the intestinal epithelium by a non-specific passive pathway and provide evidence supporting a concentration-dependent paracellular transport mechanism, although some transcellular diffusion cannot be ruled out. Considering that HePC opens epithelial tight junctions, this study shows that HePC may promote its own permeation across the intestinal barrier.

Substrate analysis of the Pneumocystis carinii protein kinases PcCbk1 and PcSte20 using yeast proteome microarrays provides a novel method for Pneumocystis signalling biology.

PubMed

Kottom, Theodore J; Limper, Andrew H

2011-10-01

Pneumocystis carinii (Pc) undergoes morphological transitions between cysts and trophic forms. We have previously described two Pc serine/threonine kinases, termed PcCbk1 and PcSte20, with PcSte20 belonging to a family of kinases involved in yeast mating, while PcCbk1 is a member of a group of protein kinases involved in regulation of cell cycle, shape, and proliferation. As Pc remains genetically intractable, knowledge on specific substrates phosphorylated by these kinases remains limited. Utilizing the phylogenetic relatedness of Pc to Saccharomyces cerevisiae, we interrogated a yeast proteome microarray containing >4000 purified protein based peptides, leading to the identification of 18 potential PcCbk1 and 15 PcSte20 substrates (Z-score > 3.0). A number of these potential protein substrates are involved in bud site selection, polarized growth, and response to mating α factor and pseudohyphal and invasive growth. Full-length open reading frames suggested by the PcCbk1 and PcSte20 protoarrays were amplified and expressed. These five proteins were used as substrates for PcCbk1 or PcSte20, with each being highly phosphorylated by the respective kinase. Finally, to demonstrate the utility of this method to identify novel PcCbk1 and PcSte20 substrates, we analysed DNA sequence data from the partially complete Pc genome database and detected partial sequence information of potential PcCbk1 kinase substrates PcPxl1 and PcInt1. We additionally identified the potential PcSte20 kinase substrate PcBdf2. Full-length Pc substrates were cloned and expressed in yeast, and shown to be phosphorylated by the respective Pc kinases. In conclusion, the yeast protein microarray represents a novel crossover technique for identifying unique potential Pc kinase substrates. Copyright © 2011 John Wiley & Sons, Ltd.

A controllable robust multiferroic GaTeCl monolayer with colossal 2D ferroelectricity and desirable multifunctionality.

PubMed

Zhang, Shi-Hao; Liu, Bang-Gui

2018-03-29

We propose through first-principles investigation that the GaTeCl monolayer is an excellent two-dimensional (2D) multiferroic with giant mechanical anisotropy. The calculated phonon spectrum, molecular dynamic simulations, and elastic moduli confirm its dynamic and mechanical stability, and our cleavage energy analysis shows that exfoliating one GaTeCl monolayer from the existing GaTeCl bulk is feasible. The calculated in-plane ferroelectric polarization reaches 578 pC m-1. The energy barriers per formula unit of the ferroelastic 90° rotational and ferroelectric reversal transitions are 476 meV and 754 meV, respectively, being the greatest in the 2D multiferroics family so far. Importantly, on the other hand, a tensile stress of 4.7 N m-1 perpendicular to the polarization can drive the polarization to rotate by 90°. These can make the GaTeCl monolayer have not only robust ferroelasticity and ferroelectricity but also easy mechanical controllability. Furthermore, the GaTeCl monolayer has giant piezoelectricity and optical second harmonic generation, especially in the range of visible light, and a tensile stress of 0.3 N m-1 along the polarization can make the indirect gap transit to the direct gap. These interesting mechanical, electronic, and optical properties of the GaTeCl monolayer show its great potential in high-performance multi-functional applications.

The Multi-Scale Environment of RS Cnc from CO and HI Observations

NASA Astrophysics Data System (ADS)

Hoai, D. T.; Matthews, L. D.; Winters, J. M.; Nhung, P. T.; Gérard, E.; Libert, Y.; Le Bertre, T.

2015-08-01

We present a detailed study of the circumstellar gas distribution and kinematics of the semi-regular variable star RS Cnc on spatial scales ranging from ˜1″ (˜150 AU) to ˜6' (˜0.24 pc). The close environment of RS Cnc (from 1 to 20″) can be described with a model in which the density and velocity vary smoothly from the equatorial plane to the polar axis. In this model the mass loss rate is higher along the polar directions than in the equatorial plane, which does not favor current models invoking stellar rotation or a magnetic field as the cause of the axi-symmetry. Outside this region, the study of which is limited by the photo-dissociation of CO, HI data at 21 cm show that the flow is slowed down at a typical distance of 1' (˜0.04 pc). Further away (1 to 6', or 0.04 to 0.24 pc), the flow is distorted by the relative motion of the star with respect to the interstellar medium.

pcDNA-IL-12 vaccination blocks eosinophilic inflammation but not airway hyperresponsiveness following murine Toxocara canis infection.

PubMed

Malheiro, Adriana; Aníbal, Fernanda F; Martins-Filho, Olindo Assis; Teixeira-Carvalho, Andréa; Perini, Adenir; Martins, Milton A; Medeiros, Alexandra I; Turato, Walter M; Acencio, Milene P M; Brandão, Izaíra T; Nomizo, Auro; Silva, Célio L; Faccioli, Lúcia H

2008-01-17

We have investigated the effect of pcDNA3-CpG and pcDNA-IL-12, delivered by intradermal gene gun administration, on the blood/lung eosinophilia, airway hyperresponsiveness as well as the immune response in a murine model of toxocariasis. Our results demonstrated that pcDNA-IL-12 but not pcDNA3-CpG vaccination led to a persistent lower blood/bronchoalveolar eosinophilia following Toxocara canis infection, as pcDNA3-CpG led only to an early transient blockage of eosinophil transmigration into bronchoalveolar fluid following T. canis infection. Prominent Type-1 immune response was pointed out as the hallmark of T. canis infection following pcDNA-IL-12 vaccination. Outstanding IFN-gamma/IL-4 ratio besides low levels of IgG1 with subsequent high IgG2a/IgG1 ratio further characterized a Type-1 polarized immunological profile in pcDNA-IL-12-vaccinated animals. Nevertheless, only pcDNA3-CpG was able to prevent airway hyperresponsiveness induced by T. canis infection. The persistent airway hyperresponsiveness observed in pcDNA-IL-12-vaccinated animals demonstrated that the airway constriction involved other immunological mediator than those blocked by pcDNA-IL-12. Together, these data indicated that pcDNA-IL-12 and pcDNA3-CpG vaccines have distinct therapeutic benefits regarding the eosinophilic inflammation/airway hyperresponsiveness triggered by T. canis infection, suggesting their possible use in further combined therapeutic interventions.

Near-infrared polarimetric adaptive optics observations of NGC 1068: a torus created by a hydromagnetic outflow wind

NASA Astrophysics Data System (ADS)

Lopez-Rodriguez, E.; Packham, C.; Jones, T. J.; Nikutta, R.; McMaster, L.; Mason, R. E.; Elvis, M.; Shenoy, D.; Alonso-Herrero, A.; Ramírez, E.; González Martín, O.; Hönig, S. F.; Levenson, N. A.; Ramos Almeida, C.; Perlman, E.

2015-09-01

We present J' and K' imaging linear polarimetric adaptive optics observations of NGC 1068 using MMT-Pol on the 6.5-m MMT. These observations allow us to study the torus from a magnetohydrodynamical (MHD) framework. In a 0.5 arcsec (30 pc) aperture at K', we find that polarization arising from the passage of radiation from the inner edge of the torus through magnetically aligned dust grains in the clumps is the dominant polarization mechanism, with an intrinsic polarization of 7.0 ± 2.2 per cent. This result yields a torus magnetic field strength in the range of 4-82 mG through paramagnetic alignment, and 139^{+11}_{-20} mG through the Chandrasekhar-Fermi method. The measured position angle (P.A.) of polarization at K' is found to be similar to the P.A. of the obscuring dusty component at few parsec scales using infrared interferometric techniques. We show that the constant component of the magnetic field is responsible for the alignment of the dust grains, and aligned with the torus axis on to the plane of the sky. Adopting this magnetic field configuration and the physical conditions of the clumps in the MHD outflow wind model, we estimate a mass outflow rate ≤0.17 M⊙ yr-1 at 0.4 pc from the central engine for those clumps showing near-infrared dichroism. The models used were able to create the torus in a time-scale of ≥105 yr with a rotational velocity of ≤1228 km s-1 at 0.4 pc. We conclude that the evolution, morphology and kinematics of the torus in NGC 1068 can be explained within a MHD framework.

The South American Meridional B-field Array (SAMBA) and Pc4-5 Wave Studies

NASA Astrophysics Data System (ADS)

Sterner, Lt. Nathan; Zesta, Eftyhia; Boudouridis, Athanasios; Moldwin, Mark; Yizengaw, Endawoke; Chi, Peter

The Antarctic continent, the only landmass in the southern polar region, offers the unique opportunity for observations that geomagnetically range from polar latitudes to well into the inner magnetosphere, thus enabling conjugate observations in a wide range of geomagnetic lat-itudes. The SAMBA (South American Meridional B-field Array) chain is a meridional chain of 12 magnetometers, 11 of them at L=1.1 to L=2.5 along the coast of Chile and in the Antarc-tica peninsula, and one auroral station along the same meridian. SAMBA is conjugate to the northern hemisphere MEASURE and McMAC chains, offering unique opportunities for inter-hemispheric studies. In particular, we study asymmetries in the power of ULF waves and the role of the ionosphere in such observed asymmetries. Utilizing conjugate magnetometer stations at L=1.7 and L=2.3, we previously demonstrated that the northern hemisphere consistently shows higher ULF wave power. One possible reason for the asymmetry is solar zenith angles differences with the northern hemisphere station being closer to the ecliptic plain and having a higher power ratio. These hemispheric differences were also observed with TEC measurements indicating that the north and south conjugate ionospheres are similarly asymmetric. The initial study was done with Pc3 waves, which include the resonance frequencies for the flux tubes of our conjugate stations. We now extend the study to Pc4 and Pc5 waves that reach the lower latitudes via different mechanisms and compare these waves to the resonant Pc3 waves.

The South American Meridional B-field Array (SAMBA) and Pc4-5 Wave Studies

NASA Astrophysics Data System (ADS)

Sterner, N. L.; Zesta, E.; Boudouridis, A.; Moldwin, M.; Yizengaw, E.; Chi, P. J.

2010-12-01

The Antarctic continent, the only landmass in the southern polar region, offers the unique opportunity for observations that geomagnetically range from polar latitudes to well into the inner magnetosphere, thus enabling conjugate observations in a wide range of geomagnetic latitudes. The SAMBA (South American Meridional B-field Array) chain is a meridional chain of 12 magnetometers, 11 of them at L=1.1 to L=2.5 along the coast of Chile and in the Antarctica peninsula, and one auroral station along the same meridian. SAMBA is conjugate to the northern hemisphere MEASURE and McMAC chains, offering unique opportunities for inter-hemispheric studies. In particular, we study asymmetries in the power of ULF waves and the role of the ionosphere in such observed asymmetries. Utilizing conjugate magnetometer stations at L=1.7 and L=2.3, we previously demonstrated that the northern hemisphere consistently shows higher ULF wave power. One possible reason for the asymmetry is solar zenith angles differences with the northern hemisphere station being closer to the ecliptic plain and having a higher power ratio. These hemispheric differences were also observed with TEC measurements indicating that the north and south conjugate ionospheres are similarly asymmetric. The initial study was done with Pc3 waves, which include the resonance frequencies for the flux tubes of our conjugate stations. We now extend the study to Pc4 and Pc5 waves that reach the lower latitudes via different mechanisms and compare these waves to the resonant Pc3 waves.

A motion picture presentation of magnetic pulsations

NASA Technical Reports Server (NTRS)

Suzuki, A.; Kim, J. S.; Sugura, M.; Nagano, H.

1981-01-01

Using the data obtained from the IMS North American magnetometer network stations at high latitudes, a motion picture was made by a computer technique, describing time changes of Pc5 and Pi3 magnetic pulsation vectors. Examples of pulsation characteristics derived from this presentation are regional polarization changes including shifts of polarization demarcation lines, changes in the extent of an active region and its movement with time.

The cmc-value of a bolalipid with two phosphocholine headgroups and a C24 alkyl chain: Unusual binding properties of fluorescence probes to bolalipid aggregates.

PubMed

Kordts, Martin; Kerth, Andreas; Drescher, Simon; Ott, Maria; Blume, Alfred

2017-09-01

Bolalipids with a long alkyl chain and two phosphocholine polar groups self-assemble in water into two different types of aggregate structures, namely helical nanofibers at low temperature and two types of micellar aggregates at higher temperature. We tried to determine the critical aggregation concentration (cac) or critical micellar concentration (cmc) of the bolalipid tetracosane-1,24-bis(phosphocholine) (PC-C24-PC) by using different fluorescent probes. The use of pyrene or pyrene derivatives as fluorophores failed, whereas the probes 1,8-ANS and particularly bis-ANS gave consistent results. The structure of the bolalipid aggregates obviously hinders partitioning or binding of pyrene derivatives into the micellar interior, whereas 1,8-ANS and bis-ANS can bind to the surface of the aggregate structures. The observed large increase in fluorescence intensity of bis-ANS indicates that binding to the hydrophobic surface of the aggregates leads to a reduction of the dye mobility. However, binding of bis-ANS is relatively weak, so that the determination of a cac/cmc-value is difficult. Simulations of the intensity curves for PC-C24-PC lead to estimates of the cac/cmc-value of 0.3-1.0×10 -6 M, depending on the structure of the aggregates. Single molecule fluorescence correlation spectroscopy was used to determine the mobility of bis-ANS as a function of concentration of PC-C24-PC. The dye diffusion time and the molecular brightness are lower at low bolalipid concentration, when only free dye is present, and increase at higher concentration when bis-ANS is bound to the aggregates. The experimental cac/cmc-values are higher than those estimated, using an incremental method for the change in Gibbs free energy for micellization with n-alkyl-phosphocholines with only one polar group as a comparison. Apparently, for PC-C24-PC in micellar or fibrous aggregates, more CH 2 groups are exposed to water than in a conventional micelle of an n-alkyl-phosphocholine. Copyright © 2017 Elsevier Inc. All rights reserved.

Ultracompact photonic crystal polarization beam splitter based on multimode interference.

PubMed

Lu, Ming-Feng; Liao, Shan-Mei; Huang, Yang-Tung

2010-02-01

We propose a theoretical design for a compact photonic crystal (PC) polarization beam splitter (PBS) based on the multimode interference (MMI) effect. The size of a conventional MMI device designed by the self-imaging principle is not compact enough; therefore, we design a compact PC PBS based on the difference of the interference effect between TE and TM modes. Within the MMI coupler, the dependence of interference of modes on propagation distance is weak for a TE wave and strong for a TM wave; as a result, the length of the MMI section can be only seven lattice constants. Simulation results show that the insertion losses are 0.32 and 0.89 dB, and the extinction ratios are 14.4 and 17.5 dB for Port 1 (TE mode) and Port 2 (TM mode), respectively.

Wavelength-switchable passively mode-locked fiber laser with mechanically exfoliated molybdenum ditelluride on side-polished fiber

NASA Astrophysics Data System (ADS)

Wang, Guomei

2017-11-01

We experimentally investigated the nonlinear saturable absorption characteristics of molybdenum ditelluride (MoTe2) and demonstrated a wavelength-switchable mode-locked erbium-doped fiber laser (EDFL) by using MoTe2 thin film on side-polished fiber (SPF) as saturable absorber. Here, the MoTe2 thin film was efficiently fabricated via mechanical exfoliation method and transferred onto the SPF with the assistance of polydimethylsiloxane (PDMS). MoTe2-covered SPF (MSPF) exhibits the nonlinear saturable absorption for pulses with different polarization states. Optical solitons with spectral bandwidth of 1.06 (1.31) nm centered at ∼1559 (∼1528) nm and pulse duration of 2.46 (2.04) ps can be obtained from the EDFL by adjusting the polarization controller (PC) properly. The time-bandwidth product (TBP) of the pulses was calculated as 0.322 (0.344).

Influence of Picual olive ripening on virgin olive oil alteration and stability during potato frying.

PubMed

Olivero-David, Raul; Mena, Carmen; Pérez-Jimenez, M Angeles; Sastre, Blanca; Bastida, Sara; Márquez-Ruiz, Gloria; Sánchez-Muniz, Francisco J

2014-12-03

Ripening modifies oil attributes and composition. However, the influence of olive ripening on virgin olive oil (VOO) thermal oxidative stability on food-frying has not been studied yet. Oils from Picual olives of low (VOO1), medium (VOO2), and high (VOO3) ripeness were obtained, and their thermal oxidative stability during 40 potato-fryings was tested. Unused VOO1 showed higher antioxidant content and oxidative stability than VOO2 and VOO3. Polar compounds (PC), oligomers, and altered fatty acid methyl esters (polar-FAME) increased, whereas linoleic acid, polyphenols, and tocopherols decreased in the three VOOs through frying. The alteration was lower in VOO1, followed by VOO2 (0.105, 0.117, and 0.042 g/100 g oil less of PC, oligomers and polar-FAME per frying, respectively, in VOO1 than in VOO3). In conclusion, VOO obtained from low-ripeness Picual olives should be preferred when frying fresh-potatoes due to its higher thermal and oxidative stability, permitting a higher number of potato-frying uses.

Human Pancreatic Cancer Cells Induce a MyD88-Dependent Stromal Response To Promote a Tumor-Tolerant Immune Microenvironment

PubMed Central

Delitto, Daniel; Delitto, Andrea E.; DiVita, Bayli B.; Pham, Kien; Han, Song; Hartlage, Emily R.; Newby, Brittney N.; Gerber, Michael H.; Behrns, Kevin E.; Moldawer, Lyle L.; Thomas, Ryan M.; George, Thomas J.; Brusko, Todd M.; Mathews, Clayton E.; Liu, Chen; Trevino, Jose G.; Hughes, Steven J.; Wallet, Shannon M.

2016-01-01

Cancer cells exert mastery over the local tumor-associated stroma (TAS) to configure protective immunity within the tumor microenvironment. The immunomodulatory character of pancreatic lysates of patients with cancer differs from those with pancreatitis. In this study, we evaluated the crosstalk between pancreatic cancer (PC) and its TAS in primary human cell culture models. Upon exposure of TAS to PC cell-conditioned media, we documented robust secretion of IL-6 and IL-8. This TAS response was MyD88-dependent and sufficient to directly suppress both CD4+ and CD8+ T cell proliferation, inducing Th17 polarization at the expense of Th1. We found that patients possessed a similar shift in circulating effector memory Th17:Th1 ratios compared to healthy controls. The TAS response also directly suppressed CD8+ T cell-mediated cytotoxicity. Overall, our results demonstrate how TAS contributes to the production of an immunosuppressive tumor microenvironment in pancreatic cancer. PMID:27864347

Observations of cavity polaritons in one-dimensional photonic crystals containing a liquid-crystalline semiconductor based on perylene bisimide units

NASA Astrophysics Data System (ADS)

Sakata, T.; Suzuki, M.; Yamamoto, T.; Nakanishi, S.; Funahashi, M.; Tsurumachi, N.

2017-10-01

We investigated the optical transmission properties of one-dimensional photonic crystal (1D-PC) microcavity structures containing the liquid-crystalline (LC) perylene tetracarboxylic bisimide (PTCBI) derivative. We fabricated the microcavity structures for this study by two different methods and observed the cavity polaritons successfully in both samples. For one sample, since the PTCBI molecules were aligned in the cavity layer of the 1D-PC by utilizing a friction transfer method, vacuum Rabi splitting energy was strongly dependent on the polarization of the incident light produced by the peculiar optical features of the LC organic semiconductor. For the other sample, we did not utilize the friction transfer method and did not observe such polarization dependence. However, we did observe a relatively large Rabi splitting energy of 187 meV, probably due to the improvement of optical confinement effect.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Wu; Xiao, Jie; Zhang, Jian

The selection and optimization of non-aqueous electrolytes for ambient operations of lithium/air batteries has been studied. Organic solvents with low volatility and low moisture absorption are necessary to minimize the change of electrolyte compositions and the reaction between lithium anode and water during discharge process. It is critical to make the electrolytes with high polarity so that it can reduce wetting and flooding of carbon based air electrode and lead to improved battery performance. For ambient operations, the viscosity, ionic conductivity, and oxygen solubility of the electrolyte are less important than the polarity of organic solvents once the electrolyte hasmore » reasonable viscosity, conductivity, and oxygen solubility. It has been found that PC/EC mixture is the best solvent system and LiTFSI is the most feasible salt for ambient operations of Li/air batteries. Battery performance is not very sensitive to PC/EC ratio or salt concentration.« less

Underlying mechanisms of cyclic peptide inhibitors interrupting the interaction of CK2α/CK2β: comparative molecular dynamics simulation studies.

PubMed

Zhou, Yue; Zhang, Na; Chen, Wenjuan; Zhao, Lijiao; Zhong, Rugang

2016-04-07

Protein-protein interactions (PPIs) are fundamental to all biological processes. Recently, the CK2β-derived cyclic peptide Pc has been demonstrated to efficiently antagonize the CK2α/CK2β interaction and strongly affect the phosphorylation of CK2β-dependent CK2 substrate specificity. The binding affinity of Pc to CK2α is destroyed to different extents by two single-point mutations of Tyr188 to Ala (Y188A) and Phe190 to Ala (F190A), which exert negative effects on the inhibitory activity (IC50) of Pc against the CK2α/CK2β interaction from 3.0 μM to 54.0 μM and ≫100 μM, respectively. However, the structural influences of Y188A and F190A mutations on the CK2α-Pc complex remain unclear. In this study, comparative molecular dynamics (MD) simulations, principal component analysis (PCA), domain cross-correlation map (DCCM) analysis and energy calculations were performed on wild type (WT), Y188A mutant, and F190A mutant systems. The results revealed that ordered communications between hydrophobic and polar interactions were essential for CK2α-Pc binding in the WT system. In addition to the loss of the hydrogen bond between Gln36 of CK2α and Gly189 of Pc in the two mutants, the improper recognition mechanisms occurred through different pathways. These pathways included the weakened hydrophobic interactions in the Y188A mutant as well as decreased polar and hydrophobic interactions in the F190A mutant. The energy analysis results qualitatively elucidated the instability of the two mutants and energetic contributions of the key residues. This study not only revealed the structural mechanisms for the decreased binding affinity of Y188A and F190A mutant CK2α-Pc complexes, but also provided valuable clues for the rational design of CK2α/CK2β subunit interaction inhibitors with high affinity and specificity.

Profiling of polar lipids in marine oleaginous diatom Fistulifera solaris JPCC DA0580: prediction of the potential mechanism for eicosapentaenoic acid-incorporation into triacylglycerol.

PubMed

Liang, Yue; Maeda, Yoshiaki; Yoshino, Tomoko; Matsumoto, Mitsufumi; Tanaka, Tsuyoshi

2014-05-28

The marine oleaginous diatom Fistulifera solaris JPCC DA0580 is a candidate for biodiesel production because of its high lipid productivity. However, the substantial eicosapentaenoic acid (EPA) content in this strain would affect the biodiesel quality. On the other hand, EPA is also known as the essential health supplement for humans. EPAs are mainly incorporated into glycerolipids in the microalgal cell instead of the presence as free fatty acids. Therefore, the understanding of the EPA biosynthesis including the incorporation of the EPA into glycerolipids especially triacylglycerol (TAG) is fundamental for regulating EPA content for different purposes. In this study, in order to identify the biosynthesis pathway for the EPA-containing TAG species, a lipidomic characterization of the EPA-enriched polar lipids was performed by using direct infusion electrospray ionization (ESI)-Q-TRAP-MS and MS/MS analyses. The determination of the fatty acid positional distribution showed that the sn-2 position of all the chloroplast lipids and part of phosphatidylcholine (PC) species was occupied by C16 fatty acids. This result suggested the critical role of the chloroplast on the lipid synthesis in F. solaris. Furthermore, the exclusive presence of C18 fatty acids in PC highly indicated the biosynthesis of EPA on PC. Finally, the PC-based acyl-editing and head group exchange processes were proposed to be essential for the incorporation of EPA into TAG and chloroplast lipids.

Relationship between PC index and magnetospheric field-aligned currents measured by Swarm satellites

NASA Astrophysics Data System (ADS)

Troshichev, O.; Sormakov, D.; Behlke, R.

2018-03-01

The relationship between the magnetospheric field-aligned currents (FAC) monitored by the Swarm satellites and the magnetic activity PC index (which is a proxy of the solar wind energy incoming into the magnetosphere) is examined. It is shown that current intensities measured in the R1 and R2 FAC layers at the poleward and equtorward boundaries of the auroral oval are well correlated, the R2 currents being evidently secondary in relation to R1 currents and correlation in the dawn and dusk oval sectors being better than in the noon and night sectors. There is evident relationship between the PC index and the intensity of field-aligned currents in the R1 dawn and dusk layers: increase of FAC intensity in the course of substorm development is accompanied by increasing the PC index values. Correlation between PC and FAC intensities in the R2 dawn and dusk layers is also observed, but it is much weaker. No correlation is observed between PC and field-aligned currents in the midnight as well as in the noon sectors ahead of the substorm expansion phase. The results are indicative of the R1 field-aligned currents as a driver of the polar cap magnetic activity (PC index) and currents in the R2 layer.

Principal Component Noise Filtering for NAST-I Radiometric Calibration

NASA Technical Reports Server (NTRS)

Tian, Jialin; Smith, William L., Sr.

2011-01-01

The National Polar-orbiting Operational Environmental Satellite System (NPOESS) Airborne Sounder Testbed- Interferometer (NAST-I) instrument is a high-resolution scanning interferometer that measures emitted thermal radiation between 3.3 and 18 microns. The NAST-I radiometric calibration is achieved using internal blackbody calibration references at ambient and hot temperatures. In this paper, we introduce a refined calibration technique that utilizes a principal component (PC) noise filter to compensate for instrument distortions and artifacts, therefore, further improve the absolute radiometric calibration accuracy. To test the procedure and estimate the PC filter noise performance, we form dependent and independent test samples using odd and even sets of blackbody spectra. To determine the optimal number of eigenvectors, the PC filter algorithm is applied to both dependent and independent blackbody spectra with a varying number of eigenvectors. The optimal number of PCs is selected so that the total root-mean-square (RMS) error is minimized. To estimate the filter noise performance, we examine four different scenarios: apply PC filtering to both dependent and independent datasets, apply PC filtering to dependent calibration data only, apply PC filtering to independent data only, and no PC filters. The independent blackbody radiances are predicted for each case and comparisons are made. The results show significant reduction in noise in the final calibrated radiances with the implementation of the PC filtering algorithm.

Tuning magnetic exchange interactions in crystalline thin films of substituted Cobalt Phthalocyanine

NASA Astrophysics Data System (ADS)

Rawat, Naveen; Manning, Lane; Hua, Kim-Ngan; Headrick, Randall; Bishop, Michael; McGill, Stephen; Waterman, Rory; Furis, Madalina

Magnetic exchange interactions in diluted organometallic crystalline thin film alloys of Phthalocyanines (Pcs) made of a organo-soluble derivatives of Cobalt Pc and metal-free (H2Pc) molecule and is investigated. To this end, we synthesized a organosoluble CoPc and successfully employed a novel solution-based pen-writing deposition technique to fabricate long range ordered thin films of mixtures of different ratios ranging from 1:1 to 10:1 H2Pc:CoPc. Our previous magnetic circular dichroism (MCD) results on the parent CoPc crystalline thin films identified different electronic states mediating exchange interactions and indirect exchange interaction competing with superexchange interaction. This understanding of spin-dependent exchange interaction between delocalized π-electrons with unpaired d spins along with the excitonic delocalization character enabled the further tuning of these interactions by essentially varying the spatial distance between the spins. Furthermore, high magnetic field (B < 25 T) MCD and magneto-photoluminescence show evidence of spin-polarized band-edge excitons in the same materials. This work was possible due to support by the National Science Foundation, Division of Materials Research MRI, CAREER and EPM program Awards: DMR-0722451, DMR-0821268, DMR-1307017 and DMR-1056589, DMR-1229217.

Possibility of a ferromagnetic and conducting metal-organic network

NASA Astrophysics Data System (ADS)

Mabrouk, Manel; Hayn, Roland; Denawi, Hassan; Ben Chaabane, Rafik

2018-05-01

In this paper, we present first principles calculations based on the spin-polarized generalized gradient approximation with on-site Coulomb repulsion term (SGGA + U), to explore the electronic and magnetic properties of the novel planar metal-organic networks TM-Pc and TM-TCNB (where TM means a transition metal of the 3d series: Ti, V, Cr, …, or Zn, Pc - Phthalocyanine, and TCNB - Tetracyanobenzene) as free-standing sheets. This work is an extension of two earlier research works dealing with the Mn (Mabrouk et al., 2015) and Fe (Mabrouk et al., 2017) cases. Our theoretical investigations demonstrate that TM-Pc are more stable than TM-TCNB. Our results unveil that all the TM-Pc frameworks have an insulating behavior with the exception of Mn-Pc which is half-metallic and favor antiferromagnetic order in the case of our magnetic systems except for V-Pc which is ferromagnetic. In contrast, the TM-TCNB networks are metallic at least in one spin direction and exhibit long-range ferromagnetic coupling in case for magnetic structures, which represent ideal candidates and an interesting prospect of unprecedented applications in spintronics. In addition, these results may shed light to achieve a new pathway on further experimental research in molecular spintronics.

Leishmania donovani Resistance to Miltefosine Involves a Defective Inward Translocation of the Drug

PubMed Central

Pérez-Victoria, F. Javier; Castanys, Santiago; Gamarro, Francisco

2003-01-01

Miltefosine (hexadecylphosphocholine [HePC]) is the first drug approved for the oral treatment of visceral leishmaniasis. As part of a study on the mechanisms of action of this drug and on the rates of resistance to this drug, we have been working in vitro with an Leishmania donovani line that was previously shown to be 15-fold more resistant to HePC. We have studied the accumulation of [14C]HePC by L. donovani promastigotes and have found a drastic reduction (>95%) in the ability of the resistant line to internalize the drug. Binding of HePC to the plasma membrane and drug efflux from preloaded cells were similar in both drug-sensitive and -resistant lines, and no [14C]HePC metabolism was evident in either line. Resistant parasites were also unable to take up other short-chain phospholipid analogs, independently of their polar head group, even though endocytosis remained unaltered. Finally, HePC uptake was temperature and energy dependent and sensitive to the thiol-reactive agent N-ethylmaleimide. We propose that inward translocation of a short-chain phospholipid across the plasma membrane may exist in Leishmania promastigotes and that such activity is defective in the resistant line. PMID:12878496

A petrographic thin sectioning technique for evaluating composite materials

NASA Technical Reports Server (NTRS)

Parker, D. S.; Yee, A. F.

1989-01-01

Petrographic thin sectioning by a low-speed diamond saw has been used in conjunction with transmission polarized light microscopy for the characterization of the microstructure and deformation mechanisms of a variety of polymer systems. It has proven possible by these means to study three types of thermoplastic matrices for composite applications: PEEK, BPA-based polycarbonate (PC), and a rubber-modified PC. The reinforcing fibers for these matrices were in all cases AS4 carbon fibers, unidirectionally arrayed. Superior analyzability of matrix morphology and subsurface fracture processes is achieved by thin sectioning.

North Polar Radiative Flux Variability from 2002 Through 2014

NASA Technical Reports Server (NTRS)

Rutan, David; Rose, Fred; Doelling, David; Kato, Seiji; Smith, Bill, Jr.

2017-01-01

NASA's Clouds and the Earth's Radiant Energy System (CERES) project produces the SYN1Deg data product. SYN1deg provides global, 1deg gridded, hourly estimates of Top of Atmosphere (TOA) (CERES observations and calculations) and atmospheric and surface radiative flux (calculations). Examples of 12 year North Polar averages of some variables are shown to the right. Given recent interest in polar science we focus here on TOA and Surface validation of calculated irradiant fluxes. TOA upward longwave irradiance calculations match the CERES observations well both spatially and temporally with correlations remaining strong through PC 6. Compare SYN1Deg Calculations & Meteorological Teleconnections. TOA reflected shortwave irradiance calculations match the CERES observations well both spatially and temporally with correlations remaining string through PC 7. Comparing SYN1Deg calculations to teleconnection patterns requires expanding the area to 30N for EOF analyses. Correlating the Principal Components of various variables to teleconnection time series indicates which variable is most highly correlated with which teleconnection signal. The tables indicate the Pacific North American Oscillation is most correlated to the OLR EOF 1, and the North American Oscillation is correlated most closely to surface LW flux down EOF 1.

Statistical Patterns of Ionospheric Convection Derived From Mid-latitude, High-Latitude, and Polar SuperDARN HF Radar Observations

NASA Astrophysics Data System (ADS)

Thomas, E. G.; Shepherd, S. G.

2018-04-01

Over the last decade, the Super Dual Auroral Radar Network (SuperDARN) has undergone a dramatic expansion in the Northern Hemisphere with the addition of more than a dozen radars offering improved coverage at mid-latitudes (50°-60° magnetic latitude) and in the polar cap (80°-90° magnetic latitude). In this study, we derive a statistical model of ionospheric convection (TS18) using line-of-sight velocity measurements from the complete network of mid-latitude, high-latitude, and polar radars for the years 2010-2016. These climatological patterns are organized by solar wind, interplanetary magnetic field (IMF), and dipole tilt angle conditions. We find that for weak solar wind driving conditions the TS18 model patterns are largely similar to the average patterns obtained using high-latitude radar data only. For stronger solar wind driving the inclusion of mid-latitude radar data at the equatorward extent of the ionospheric convection can increase the measured cross-polar cap potential (ΦPC) by as much as 40%. We also derive an alternative model organized by the Kp index to better characterize the statistical convection under a range of magnetic activity conditions. These Kp patterns exhibit similar IMF By dependencies as the TS18 model results and demonstrate a linear increase in ΦPC with increasing Kp for a given IMF orientation. Overall, the mid-latitude radars provide a better specification of the flows within the nightside Harang reversal region for moderate to strong solar wind driving or geomagnetic activity, while the polar radars improve the quality of velocity measurements in the deep polar cap under all conditions.

Polarization Catastrophe Contributing to Rotation and Tornadic Motion in Cumulo-Nimbus Clouds

NASA Astrophysics Data System (ADS)

Handel, P. H.

2007-05-01

When the concentration of sub-micron ice particles in a cloud exceeds 2.5E21 per cubic cm, divided by the squared average number of water molecules per crystallite, the polarization catastrophe occurs. Then all ice crystallites nucleated on aerosol dust particles align their dipole moments in the same direction, and a large polarization vector field is generated in the cloud. Often this vector field has a radial component directed away from the vertical axis of the cloud. It is induced by the pre-existing electric field caused by the charged screening layers at the cloud surface, the screening shell of the cloud. The presence of a vertical component of the magnetic field of the earth creates a density of linear momentum G=DxB in the azimuthal direction, where D=eE+P is the electric displacement vector and e is the vacuum permittivity. This linear momentum density yields an angular momentum density vector directed upward in the nordic hemisphere, if the polarization vector points away from the vertical axis of the cloud. When the cloud becomes colloidally unstable, the crystallites grow beyond the size limit at which they still could carry a large ferroelectric saturation dipole moment, and the polarization vector quickly disappears. Then the cloud begins to rotate with an angular momentum that has the same direction. Due to the large average number of water molecules in a crystallite, the polarization catastrophe (PC) is present in practically all clouds, and is compensated by masking charges. In cumulo-nimbus (thunder-) clouds the collapse of the PC is rapid, and the masking charges lead to lightning, and in the upper atmosphere also to sprites, elves, and blue jets. In stratus clouds, however, the collapse is slow, and only leads to reverse polarity in dissipating clouds (minus on the bottom), as compared with growing clouds (plus on the bottom, because of the excess polarization charge). References: P.H. Handel: "Polarization Catastrophe Theory of Cloud Electricity", J. Geophysical Research 90, 5857-5863 (1985). P.H. Handel and P.B. James: "Polarization Catastrophe Model of Static Electrification and Spokes in the B-Ring of Saturn", Geophys. Res. Lett. 10, 1-4 (1983).

THE INTERSTELLAR MAGNETIC FIELD CLOSE TO THE SUN. II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frisch, P. C.; Andersson, B-G; Berdyugin, A.

2012-12-01

The magnetic field in the local interstellar medium (ISM) provides a key indicator of the galactic environment of the Sun and influences the shape of the heliosphere. We have studied the interstellar magnetic field (ISMF) in the solar vicinity using polarized starlight for stars within 40 pc of the Sun and 90 Degree-Sign of the heliosphere nose. In Frisch et al. (Paper I), we developed a method for determining the local ISMF direction by finding the best match to a group of interstellar polarization position angles obtained toward nearby stars, based on the assumption that the polarization is parallel tomore » the ISMF. In this paper, we extend the analysis by utilizing weighted fits to the position angles and by including new observations acquired for this study. We find that the local ISMF is pointed toward the galactic coordinates l, b =47 Degree-Sign {+-} 20 Degree-Sign , 25 Degree-Sign {+-} 20 Degree-Sign . This direction is close to the direction of the ISMF that shapes the heliosphere, l, b =33 Degree-Sign {+-} 4 Degree-Sign , 55 Degree-Sign {+-} 4 Degree-Sign , as traced by the center of the 'Ribbon' of energetic neutral atoms discovered by the Interstellar Boundary Explorer (IBEX) mission. Both the magnetic field direction and the kinematics of the local ISM are consistent with a scenario where the local ISM is a fragment of the Loop I superbubble. A nearby ordered component of the local ISMF has been identified in the region l Almost-Equal-To 0 Degree-Sign {yields} 80 Degree-Sign and b Almost-Equal-To 0 Degree-Sign {yields} 30 Degree-Sign , where PlanetPol data show a distance-dependent increase of polarization strength. The ordered component extends to within 8 pc of the Sun and implies a weak curvature in the nearby ISMF of {approx}0.{sup 0}25 pc{sup -1}. This conclusion is conditioned on the small sample of stars available for defining this rotation. Variations from the ordered component suggest a turbulent component of {approx}23 Degree-Sign . The ordered component and standard relations between polarization, color excess, and H{sup o} column density predict a reasonable increase of N(H) with distance in the local ISM. The similarity of the ISMF directions traced by the polarizations, the IBEX Ribbon, and pulsars inside the Local Bubble in the third galactic quadrant suggest that the ISMF is relatively uniform over spatial scales of 8-200 pc and is more similar to interarm than spiral-arm magnetic fields. The ISMF direction from the polarization data is also consistent with small-scale spatial asymmetries detected in GeV-TeV cosmic rays with a galactic origin. The peculiar geometrical relation found earlier between the cosmic microwave background dipole moment, the heliosphere nose, and the ISMF direction is supported by this study. The interstellar radiation field at {approx}975 A does not appear to play a role in grain alignment for the low-density ISM studied here.« less

Polycystin-2-dependent control of cardiomyocyte autophagy.

PubMed

Criollo, Alfredo; Altamirano, Francisco; Pedrozo, Zully; Schiattarella, Gabriele G; Li, Dan L; Rivera-Mejías, Pablo; Sotomayor-Flores, Cristian; Parra, Valentina; Villalobos, Elisa; Battiprolu, Pavan K; Jiang, Nan; May, Herman I; Morselli, Eugenia; Somlo, Stefan; de Smedt, Humbert; Gillette, Thomas G; Lavandero, Sergio; Hill, Joseph A

2018-05-01

Considerable evidence points to critical roles of intracellular Ca 2+ homeostasis in the modulation and control of autophagic activity. Yet, underlying molecular mechanisms remain unknown. Mutations in the gene (pkd2) encoding polycystin-2 (PC2) are associated with autosomal dominant polycystic kidney disease (ADPKD), the most common inherited nephropathy. PC2 has been associated with impaired Ca 2+ handling in cardiomyocytes and indirect evidence suggests that this protein may be involved in autophagic control. Here, we investigated the role for PC2 as an essential regulator of Ca 2+ homeostasis and autophagy. Activation of autophagic flux triggered by mTOR inhibition either pharmacologically (rapamycin) or by means of nutrient depletion was suppressed in cells depleted of PC2. Moreover, cardiomyocyte-specific PC2 knockout mice (αMhc-cre;Pkd2 F/F mice) manifested impaired autophagic flux in the setting of nutrient deprivation. Stress-induced autophagy was blunted by intracellular Ca 2+ chelation using BAPTA-AM, whereas removal of extracellular Ca 2+ had no effect, pointing to a role of intracellular Ca 2+ homeostasis in stress-induced cardiomyocyte autophagy. To determine the link between stress-induced autophagy and PC2-induced Ca 2+ mobilization, we over-expressed either wild-type PC2 (WT) or a Ca 2+ -channel deficient PC2 mutant (PC2-D509V). PC2 over-expression increased autophagic flux, whereas PC2-D509V expression did not. Importantly, autophagy induction triggered by PC2 over-expression was attenuated by BAPTA-AM, supporting a model of PC2-dependent control of autophagy through intracellular Ca 2+ . Furthermore, PC2 ablation was associated with impaired Ca 2+ handling in cardiomyocytes marked by partial depletion of sarcoplasmic reticulum Ca 2+ stores. Finally, we provide evidence that Ca 2+ -mediated autophagy elicited by PC2 is a mechanism conserved across multiple cell types. Together, this study unveils PC2 as a novel regulator of autophagy acting through control of intracellular Ca 2+ homeostasis. Copyright © 2018. Published by Elsevier Ltd.

PV-Diesel Hybrid SCADA Experiment Network Design

NASA Technical Reports Server (NTRS)

Kalu, Alex; Durand, S.; Emrich, Carol; Ventre, G.; Wilson, W.; Acosta, R.

1999-01-01

The essential features of an experimental network for renewable power system satellite based supervisory, control and data acquisition (SCADA) are communication links, controllers, diagnostic equipment and a hybrid power system. Required components for implementing the network consist of two satellite ground stations, to satellite modems, two 486 PCs, two telephone receivers, two telephone modems, two analog telephone lines, one digital telephone line, a hybrid-power system equipped with controller and a satellite spacecraft. In the technology verification experiment (TVE) conducted by Savannah State University and Florida Solar Energy Center, the renewable energy hybrid system is the Apex-1000 Mini-Hybrid which is equipped with NGC3188 for user interface and remote control and the NGC2010 for monitoring and basic control tasks. This power system is connected to a satellite modem via a smart interface, RS232. Commands are sent to the power system control unit through a control PC designed as PC1. PC1 is thus connected to a satellite model through RS232. A second PC, designated PC2, the diagnostic PC is connected to both satellite modems via separate analog telephone lines for checking modems'health. PC2 is also connected to PC1 via a telephone line. Due to the unavailability of a second ground station for the ACTS, one ground station is used to serve both the sending and receiving functions in this experiment. Signal is sent from the control PC to the Hybrid system at a frequency f(sub 1), different from f(sub 2), the signal from the hybrid system to the control PC. f(sub l) and f(sub 2) are sufficiently separated to avoid interference.

A prospective study of Trichomonas vaginalis and prostate cancer risk among African American men.

PubMed

Fowke, Jay H; Han, Xijing; Alderete, J F; Moses, Kelvin A; Signorello, Lisa B; Blot, William J

2016-04-18

African Americans (AA) have a higher prevalence of Trichomonas vaginalis (Tv) infection and a higher prostate (PC) risk. Past studies suggest an association between Tv seropositivity and PC, and therefore we prospectively investigated this association among AA men. Incident PC cases were individually matched to controls in a nested case-control study within the Southern Community Cohort Study (SCCS). Primary analysis included 296 PC cases and 497 race-matched controls. Levels of Tv antibody response were measured by ELISA in serum collected at baseline. Tv antibody response did not significantly differ between cases and controls overall or within AA participants (253 AA cases). There were no significant associations or trends between levels of Tv response and PC risk or the diagnosis of aggressive PC. We found no evidence of a prospective association between baseline Tv infection and PC risk in AA men. Tv infection in men may have substantial health implications in HIV transmission and reproductive outcomes, but may not impact future PC risk in AA men at high-risk for PC. Further efforts need to define past vs. present Tv infection and to separate pathophysiology from PC detection.

Magnetic Fields in the Massive Dense Cores of the DR21 Filament: Weakly Magnetized Cores in a Strongly Magnetized Filament

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ching, Tao-Chung; Lai, Shih-Ping; Zhang, Qizhou

We present Submillimeter Array 880 μ m dust polarization observations of six massive dense cores in the DR21 filament. The dust polarization shows complex magnetic field structures in the massive dense cores with sizes of 0.1 pc, in contrast to the ordered magnetic fields of the parsec-scale filament. The major axes of the massive dense cores appear to be aligned either parallel or perpendicular to the magnetic fields of the filament, indicating that the parsec-scale magnetic fields play an important role in the formation of the massive dense cores. However, the correlation between the major axes of the cores andmore » the magnetic fields of the cores is less significant, suggesting that during the core formation, the magnetic fields below 0.1 pc scales become less important than the magnetic fields above 0.1 pc scales in supporting a core against gravity. Our analysis of the angular dispersion functions of the observed polarization segments yields a plane-of-sky magnetic field strength of 0.4–1.7 mG for the massive dense cores. We estimate the kinematic, magnetic, and gravitational virial parameters of the filament and the cores. The virial parameters show that the gravitational energy in the filament dominates magnetic and kinematic energies, while the kinematic energy dominates in the cores. Our work suggests that although magnetic fields may play an important role in a collapsing filament, the kinematics arising from gravitational collapse must become more important than magnetic fields during the evolution from filaments to massive dense cores.« less

Fabrication of field-effect transistor utilizing oriented thin film of octahexyl-substituted phthalocyanine and its electrical anisotropy based on columnar structure

NASA Astrophysics Data System (ADS)

Ohmori, Masashi; Nakatani, Mitsuhiro; Kajii, Hirotake; Miyamoto, Ayano; Yoneya, Makoto; Fujii, Akihiko; Ozaki, Masanori

2018-03-01

Field-effect transistors with molecularly oriented thin films of metal-free non-peripherally octahexyl-substituted phthalocyanine (C6PcH2), which characteristically form a columnar structure, have been fabricated, and the electrical anisotropy of C6PcH2 has been investigated. The molecularly oriented thin films of C6PcH2 were prepared by the bar-coating technique, and the uniform orientation in a large area and the surface roughness at a molecular level were observed by polarized spectroscopy and atomic force microscopy, respectively. The field effect mobilities parallel and perpendicular to the column axis of C6PcH2 were estimated to be (1.54 ± 0.24) × 10-2 and (2.10 ± 0.23) × 10-3 cm2 V-1 s-1, respectively. The electrical anisotropy based on the columnar structure has been discussed by taking the simulated results obtained by density functional theory calculation into consideration.

An eastward propagating compressional Pc 5 wave observed by AMPTE/CCE in the postmidnight sector. [Active Magnetospheric Particle Tracer Explorers

NASA Technical Reports Server (NTRS)

Takahashi, K.; Mcentire, R. W.; Zanetti, L. J.; Lopez, R. E.; Kistler, L. M.

1987-01-01

This paper presents a detailed analysis of a compressional Pc 5 wave observed in the postmidnight sector on July 21, 1986, using data from the magnetometer, the charge-energy-mass spectrometer, and the medium-energy particle analyzer aboard the AMPTE/Charge Composition Explorer (CCE) spacecraft. The Pc 5 wave exhibited harmonically related transverse and compressional magnetic oscillations, modulation of the flux of medium energy protons, and a large azimuthal wave number, i.e., properties that are similar to those of compressional Pc5 waves observed previously at geostationary orbit. The unique observations recorded by the AMPTE/CCE included the occurrence of the wave in the postmidnight sector, its sunward propagation with respect to the spacecraft, and the left-handed polarization of the perturbed magnetic field. In spite of the morphological uniqueness observed, the excitation of the July 21 event is considered to be due to the same type of instability as operates at geostationary orbit.

An eastward propagating compressional Pc 5 wave observed by AMPTE/CCE in the postmidnight sector

NASA Astrophysics Data System (ADS)

Takahashi, K.; Lopez, R. E.; McEntire, R. W.; Zanetti, L. J.; Kistler, L. M.; Ipavich, F. M.

1987-12-01

This paper presents a detailed analysis of a compressional Pc 5 wave observed in the postmidnight sector on July 21, 1986, using data from the magnetometer, the charge-energy-mass spectrometer, and the medium-energy particle analyzer aboard the AMPTE/Charge Composition Explorer (CCE) spacecraft. The Pc 5 wave exhibited harmonically related transverse and compressional magnetic oscillations, modulation of the flux of medium energy protons, and a large azimuthal wave number, i.e., properties that are similar to those of compressional Pc5 waves observed previously at geostationary orbit. The unique observations recorded by the AMPTE/CCE included the occurrence of the wave in the postmidnight sector, its sunward propagation with respect to the spacecraft, and the left-handed polarization of the perturbed magnetic field. In spite of the morphological uniqueness observed, the excitation of the July 21 event is considered to be due to the same type of instability as operates at geostationary orbit.

Calpain-mediated proteolysis of polycystin-1 C-terminus induces JAK2 and ERK signal alterations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Hyunho; Department of Medicine, University of Maryland, Baltimore, MD; Kang, Ah-Young

2014-01-01

Autosomal dominant polycystic kidney disease (ADPKD), a hereditary renal disease caused by mutations in PKD1 (85%) or PKD2 (15%), is characterized by the development of gradually enlarging multiple renal cysts and progressive renal failure. Polycystin-1 (PC1), PKD1 gene product, is an integral membrane glycoprotein which regulates a number of different biological processes including cell proliferation, apoptosis, cell polarity, and tubulogenesis. PC1 is a target of various proteolytic cleavages and proteosomal degradations, but its role in intracellular signaling pathways remains poorly understood. Herein, we demonstrated that PC1 is a novel substrate for μ- and m-calpains, which are calcium-dependent cysteine proteases. Overexpressionmore » of PC1 altered both Janus-activated kinase 2 (JAK2) and extracellular signal-regulated kinase (ERK) signals, which were independently regulated by calpain-mediated PC1 degradation. They suggest that the PC1 function on JAK2 and ERK signaling pathways might be regulated by calpains in response to the changes in intracellular calcium concentration. - Highlights: • Polycystin-1 is a target of ubiquitin-independent degradation by calpains. • The PEST domain is required for calpain-mediated degradation of polycystin-1. • Polycystin-1 may independently regulate JAK2 and ERK signaling pathways.« less

Protein C deficiency in insulin-dependent diabetes: a hyperglycemia-related phenomenon.

PubMed

Ceriello, A; Quatraro, A; Dello Russo, P; Marchi, E; Barbanti, M; Milani, M R; Giugliano, D

1990-08-13

In 30 insulin-dependent diabetic patients protein C (PC) antigen and PC activity were significantly lower than those of matched control healthy subjects. An inverse correlation between fasting plasma glucose and both PC concentration and activity was present in diabetics, while a direct correlation between PC concentration and PC activity was observed. Induced hyperglycemia in diabetic and normal subjects was able to decrease both PC antigen levels and PC activity, and heparin reversed in part this effect. In diabetic patients euglycemia obtained by insulin infusion restored to normal the depressed PC levels. Heparin did not alter both the basal PC concentration and activity in healthy controls. These data stress the major role of hyperglycemia in determining PC decrease in diabetics, and suggest that PC reduction is probably associated to hyperglycemia-enhanced thrombin formation.

Ultrafast Decay of the Solvated Electron in a Neat Polar Solvent: The Unusual Case of Propylene Carbonate.

PubMed

Le Caër, Sophie; Ortiz, Daniel; Marignier, Jean-Louis; Schmidhammer, Uli; Belloni, Jacqueline; Mostafavi, Mehran

2016-01-07

The behavior of carbonates is critical for a detailed understanding of aging phenomena in Li-ion batteries. Here we study the first reaction stages of propylene carbonate (PC), a cyclical carbonate, by picosecond pulse radiolysis. An absorption band with a maximum around 1360 nm is observed at 20 ps after the electron pulse and is shifted to 1310 nm after 50 ps. This band presents the features of a solvated electron absorption band, the solvation lasting up to 50 ps. Surprisingly, in this polar solvent, the solvated electron follows an ultrafast decay and disappears with a half time of 360 ps. This is attributed to the formation of a radical anion PC(-•). The yield of the solvated electron is low, suggesting that the radical anions are mainly directly produced from presolvated electrons. These results demonstrate that the initial electron transfers mechanisms are strongly different in linear compared with cyclical carbonates.

Analytical study of mode degeneracy in non-Hermitian photonic crystals with TM-like polarization

NASA Astrophysics Data System (ADS)

Yin, Xuefan; Liang, Yong; Ni, Liangfu; Wang, Zhixin; Peng, Chao; Li, Zhengbin

2017-08-01

We present a study of the mode degeneracy in non-Hermitian photonic crystals (PC) with TM-like polarization and C4 v symmetry from the perspective of the coupled-wave theory (CWT). The CWT framework is extended to include TE-TM coupling terms which are critical for modeling the accidental triple degeneracy within non-Hermitian PC systems. We derive the analytical form of the wave function and the condition of Dirac-like-cone dispersion when radiation loss is relatively small. We find that, similar to a real Dirac cone, the Dirac-like cone in non-Hermitian PCs possesses good linearity and isotropy, even with a ring of exceptional points (EPs) inevitably existing in the vicinity of the second-order Γ point. However, the Berry phase remains zero at the Γ point, indicating the cone does not obey the Dirac equation and is only a Dirac-like cone. The topological modal interchange phenomenon and nonzero Berry phase of the EPs are also discussed.

A First Look at BISTRO Observations of the ρ Oph-A core

NASA Astrophysics Data System (ADS)

Kwon, Jungmi; Doi, Yasuo; Tamura, Motohide; Matsumura, Masafumi; Pattle, Kate; Berry, David; Sadavoy, Sarah; Matthews, Brenda C.; Ward-Thompson, Derek; Hasegawa, Tetsuo; Furuya, Ray S.; Pon, Andy; Di Francesco, James; Arzoumanian, Doris; Hayashi, Saeko S.; Kawabata, Koji S.; Onaka, Takashi; Choi, Minho; Kang, Miju; Hoang, Thiem; Lee, Chang Won; Lee, Sang-Sung; Liu, Hong-Li; Liu, Tie; Inutsuka, Shu-ichiro; Eswaraiah, Chakali; Bastien, Pierre; Kwon, Woojin; Lai, Shih-Ping; Qiu, Keping; Coudé, Simon; Franzmann, Erica; Friberg, Per; Graves, Sarah F.; Greaves, Jane S.; Houde, Martin; Johnstone, Doug; Kirk, Jason M.; Koch, Patrick M.; Li, Di; Parsons, Harriet; Rao, Ramprasad; Rawlings, Mark G.; Shinnaga, Hiroko; van Loo, Sven; Aso, Yusuke; Byun, Do-Young; Chen, Huei-Ru; Chen, Mike C.-Y.; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Chrysostomou, Antonio; Chung, Eun Jung; Drabek-Maunder, Emily; Eyres, Stewart P. S.; Fiege, Jason; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Griffin, Matt J.; Gu, Qilao; Hatchell, Jennifer; Holland, Wayne; Inoue, Tsuyoshi; Iwasaki, Kazunari; Jeong, Il-Gyo; Kang, Ji-hyun; Kang, Sung-ju; Kemper, Francisca; Kim, Gwanjeong; Kim, Jongsoo; Kim, Kee-Tae; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Lacaille, Kevin M.; Lee, Jeong-Eun; Li, Dalei; Li, Hua-bai; Liu, Junhao; Liu, Sheng-Yuan; Lyo, A.-Ran; Mairs, Steve; Moriarty-Schieven, Gerald H.; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Peretto, Nicolas; Pyo, Tae-Soo; Qian, Lei; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-Franois; Savini, Giorgio; Scaife, Anna M. M.; Soam, Archana; Tang, Ya-Wen; Tomisaka, Kohji; Wang, Hongchi; Wang, Jia-Wei; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Yuan, Jinghua; Zhang, Chuan-Peng; Zhang, Guoyin; Zhou, Jianjun; Zhu, Lei; André, Philippe; Dowell, C. Darren; Falle, Sam; Tsukamoto, Yusuke; Nakagawa, Takao; Kanamori, Yoshihiro; Kataoka, Akimasa; Kobayashi, Masato I. N.; Nagata, Tetsuya; Saito, Hiro; Seta, Masumichi; Zenko, Tetsuya

2018-05-01

We present 850 μm imaging polarimetry data of the ρ Oph-A core taken with the Submillimeter Common-User Bolometer Array-2 (SCUBA-2) and its polarimeter (POL-2) as part of our ongoing survey project, {\\boldsymbol{B}}-fields In STar forming RegiOns (BISTRO). The polarization vectors are used to identify the orientation of the magnetic field projected on the plane of the sky at a resolution of 0.01 pc. We identify 10 subregions with distinct polarization fractions and angles in the 0.2 pc ρ Oph-A core; some of them can be part of a coherent magnetic field structure in the ρ Oph region. The results are consistent with previous observations of the brightest regions of ρ Oph-A, where the degrees of polarization are at a level of a few percent, but our data reveal for the first time the magnetic field structures in the fainter regions surrounding the core where the degree of polarization is much higher (>5%). A comparison with previous near-infrared polarimetric data shows that there are several magnetic field components that are consistent at near-infrared and submillimeter wavelengths. Using the Davis–Chandrasekhar–Fermi method, we also derive magnetic field strengths in several subcore regions, which range from approximately 0.2 to 5 mG. We also find a correlation between the magnetic field orientations projected on the sky and the core centroid velocity components.

Multipoint Spacecraft Observations of Long-Lasting Poloidal Pc4 Pulsations in the Dayside Magnetosphere on 1-2 May 2014

NASA Technical Reports Server (NTRS)

Korotova, Galina; Sibeck, David; Engebretson, Mark; Wygant, John; Thaller, Scott; Spence, Harlan; Kletzing, Craig; Angelopoulos, Vassilis; Redmon, Robert

2016-01-01

We use magnetic field and plasma observations from the Van Allen Probes, Time History of Events and Macroscale Interactions during Substorms (THEMIS) and Geostationary Operational Environmental Satellite system (GOES) spacecraft to study the spatial and temporal characteristics of long-lasting poloidal Pc4 pulsations in the dayside magnetosphere. The pulsations were observed after the main phase of a moderate storm during low geomagnetic activity. The pulsations occurred during various interplanetary conditions and the solar wind parameters do not seem to control the occurrence of the pulsations. The most striking feature of the Pc4 magnetic field pulsations was their occurrence at similar locations during three of four successive orbits. We used this information to study the latitudinal nodal structure of the pulsations and demonstrated that the latitudinal extent of the magnetic field pulsations did not exceed 2 Earth radii (R(sub E)). A phase shift between the azimuthal and radial components of the electric and magnetic fields was observed from Z(sub SM) = 0.30 R(sub E) to Z(sub SM) = -0.16 R(sub E). We used magnetic and electric field data from Van Allen Probes to determine the structure of ULF waves. We showed that the Pc4 magnetic field pulsations were radially polarized and are the second-mode harmonic waves. We suggest that the spacecraft were near a magnetic field null during the second orbit when they failed to observe the magnetic field pulsations at the local times where pulsations were observed on previous and successive orbits. We investigated the spectral structure of the Pc4 pulsations. Each spacecraft observed a decrease of the dominant period as it moved to a smaller L shell (stronger magnetic field strength). We demonstrated that higher frequencies occurred at times and locations where Alfven velocities were greater, i.e., on Orbit 1. There is some evidence that the periods of the pulsations increased during the plasmasphere refilling following the storm.

Coordinated Polar Spacecraft, Geosynchronous Spacecraft, and Ground-based Observations of Magnetopause Oscillations and Pc5 Waves in the Magnetosphere

NASA Technical Reports Server (NTRS)

Le, G.; Chen, S.; Zheng, Y.; Russell, C. T.; Slavin, J. A.; Huang, C.-S.; Petrinec, S. S.; Moore, T. E.; Samson, J.; Singer, H. J.

2005-01-01

In this paper, we present in situ observations of surface waves at the magnetopause and oscillatory magnetospheric field lines, and coordinated observations Pc5 waves at geosynchronous orbit by the GOES spacecraft, and on the ground by CANOPUS and 210 Degree Magnetic Meridian (210MMJ magnetometer arrays. On February 7,2002 during a highspeed solar wind stream, the Polar spacecraft was skimming the magnetopause in a post-noon meridian plane for approximately 3 hours. During this interval, it made two short excursions and a few partial crossings into the magnetosheath and observed quasi-periodic cold ion bursts in the region adjacent to the magnetopause current layer. The multiple magnetopause crossings as well as the velocity of the cold ion bursts indicate that the magnetopause was oscillating with about 6 minute period. Simultaneous observations of Pc5 waves at geosynchronous orbit by the GOES spacecraft and on the ground by the CANOPUS magnetometer array reveal that these magnetospheric pulsations were forced oscillations of magnetic field lines directly driven by the magnetopause oscillations. The magnetospheric pulsations occurred only in a limited longitudinal region in the post-noon dayside sector, and were not a global phenomenon as one would expect for global field line resonance. Thus, the magnetopause oscillations at the source were also limited to a localized region spanning about 4 hours in local time.

Imaging and Variability Studies of CTA 102 during the 2016 January γ-ray Flare

NASA Astrophysics Data System (ADS)

Li, Xiaofeng; Mohan, P.; An, T.; Hong, Xiaoyu; Cheng, Xiaopeng; Yang, Jun; Zhang, Yingkang; Zhang, Zhongli; Zhao, Wei

2018-02-01

The γ-ray-bright blazar CTA 102 is studied using imaging (new 15 GHz and archival 43 GHz Very Long Baseline Array, VLBA data) and time variable optical flux density, polarization degree, and electric vector position angle (EVPA) spanning between 2015 June 1 and 2016 October 1, covering a prominent γ-ray flare during 2016 January. The pc-scale jet indicates expansion with oscillatory features up to 17 mas. Component proper motions are in the range 0.04–0.33 mas yr‑1 with acceleration up to 1.2 mas followed by a slowing down beyond 1.5 mas. A jet bulk Lorentz factor ≥17.5, position angle of 128.°3, inclination angle ≤6.°6 and intrinsic half opening angle ≤1.°8 are derived from the VLBA data. These inferences are employed in a helical jet model to infer long-term variability in flux density, polarization degree, EVPA, and a rotation of the Stokes Q and U parameters. A core distance of r core,43 GHz = 22.9 pc, and a magnetic field strength at 1 pc and the core location of 1.57 G and 0.07 G, respectively, are inferred using the core-shift method. The study is useful in the context of estimating jet parameters and in offering clues to distinguish mechanisms responsible for variability over different timescales.

The effect of an offset polar cap dipolar magnetic field on the modeling of the Vela pulsar’s γ-ray light curves

PubMed Central

Barnard, M.; Venter, C.; Harding, A. K.

2018-01-01

We performed geometric pulsar light curve modeling using static, retarded vacuum, and offset polar cap (PC) dipole B-fields (the latter is characterized by a parameter ε), in conjunction with standard two-pole caustic (TPC) and outer gap (OG) emission geometries. The offset-PC dipole B-field mimics deviations from the static dipole (which corresponds to ε = 0). In addition to constant-emissivity geometric models, we also considered a slot gap (SG) E-field associated with the offset-PC dipole B-field and found that its inclusion leads to qualitatively different light curves. Solving the particle transport equation shows that the particle energy only becomes large enough to yield significant curvature radiation at large altitudes above the stellar surface, given this relatively low E-field. Therefore, particles do not always attain the radiation-reaction limit. Our overall optimal light curve fit is for the retarded vacuum dipole field and OG model, at an inclination angle α=78−1+1° and observer angle ζ=69−1+2°. For this B-field, the TPC model is statistically disfavored compared to the OG model. For the static dipole field, neither model is significantly preferred. We found that smaller values of ε are favored for the offset-PC dipole field when assuming constant emissivity, and larger ε values favored for variable emissivity, but not significantly so. When multiplying the SG E-field by a factor of 100, we found improved light curve fits, with α and ζ being closer to best fits from independent studies, as well as curvature radiation reaction at lower altitudes. PMID:29681648

Cold-induced vasoconstriction may persist long after cooling ends: an evaluation of multiple cryotherapy units

PubMed Central

Khoshnevis, Sepideh; Craik, Natalie K.

2015-01-01

Purpose Localized cooling is widely used in treating soft tissue injuries by modulating swelling, pain, and inflammation. One of the primary outcomes of localized cooling is vasoconstriction within the underlying skin. It is thought that in some instances, cryotherapy may be causative of tissue necrosis and neuropathy via cold-induced ischaemia leading to nonfreezing cold injury (NFCI). The purpose of this study is to quantify the magnitude and persistence of vasoconstriction associated with cryotherapy. Methods Data are presented from testing with four different FDA approved cryotherapy devices. Blood perfusion and skin temperature were measured at multiple anatomical sites during baseline, active cooling, and passive rewarming periods. Results Local cutaneous blood perfusion was depressed in response to cooling the skin surface with all devices, including the DonJoy (DJO, p = 2.6 × 10−8), Polar Care 300 (PC300, p = 1.1 × 10−3), Polar Care 500 Lite (PC500L, p = 0.010), and DeRoyal T505 (DR505, p = 0.016). During the rewarming period, parasitic heat gain from the underlying tissues and the environment resulted in increased temperatures of the skin and pad for all devices, but blood perfusion did not change significantly, DJO (n.s.), PC300 (n.s.), PC500L (n.s.), and DR505 (n.s.). Conclusions The results demonstrate that cryotherapy can create a deep state of vasoconstriction in the local area of treatment. In the absence of independent stimulation, the condition of reduced blood flow persists long after cooling is stopped and local temperatures have rewarmed towards the normal range, indicating that the maintenance of vasoconstriction is not directly dependent on the continuing existence of a cold state. The depressed blood flow may dispose tissue to NFCI. PMID:24562697

Cold-induced vasoconstriction may persist long after cooling ends: an evaluation of multiple cryotherapy units.

PubMed

Khoshnevis, Sepideh; Craik, Natalie K; Diller, Kenneth R

2015-09-01

Localized cooling is widely used in treating soft tissue injuries by modulating swelling, pain, and inflammation. One of the primary outcomes of localized cooling is vasoconstriction within the underlying skin. It is thought that in some instances, cryotherapy may be causative of tissue necrosis and neuropathy via cold-induced ischaemia leading to nonfreezing cold injury (NFCI). The purpose of this study is to quantify the magnitude and persistence of vasoconstriction associated with cryotherapy. Data are presented from testing with four different FDA approved cryotherapy devices. Blood perfusion and skin temperature were measured at multiple anatomical sites during baseline, active cooling, and passive rewarming periods. Local cutaneous blood perfusion was depressed in response to cooling the skin surface with all devices, including the DonJoy (DJO, p = 2.6 × 10(-8)), Polar Care 300 (PC300, p = 1.1 × 10(-3)), Polar Care 500 Lite (PC500L, p = 0.010), and DeRoyal T505 (DR505, p = 0.016). During the rewarming period, parasitic heat gain from the underlying tissues and the environment resulted in increased temperatures of the skin and pad for all devices, but blood perfusion did not change significantly, DJO (n.s.), PC300 (n.s.), PC500L (n.s.), and DR505 (n.s.). The results demonstrate that cryotherapy can create a deep state of vasoconstriction in the local area of treatment. In the absence of independent stimulation, the condition of reduced blood flow persists long after cooling is stopped and local temperatures have rewarmed towards the normal range, indicating that the maintenance of vasoconstriction is not directly dependent on the continuing existence of a cold state. The depressed blood flow may dispose tissue to NFCI.

The Effect of an Offset Polar Cap Dipolar Magnetic Field on the Modeling of the Vela Pulsar's Gamma-Ray Light Curves

NASA Technical Reports Server (NTRS)

Barnard, M.; Venter, C.; Harding, A. K.

2016-01-01

We performed geometric pulsar light curve modeling using static, retarded vacuum, and offset polar cap (PC) dipole B-fields (the latter is characterized by a parameter epsilon), in conjunction with standard two-pole caustic (TPC) and outer gap (OG) emission geometries. The offset-PC dipole B-field mimics deviations from the static dipole (which corresponds to epsilon equals 0). In addition to constant-emissivity geometric models, we also considered a slot gap (SG) E-field associated with the offset-PC dipole B-field and found that its inclusion leads to qualitatively different light curves. Solving the particle transport equation shows that the particle energy only becomes large enough to yield significant curvature radiation at large altitudes above the stellar surface, given this relatively low E-field. Therefore, particles do not always attain the radiation-reaction limit. Our overall optimal light curve fit is for the retarded vacuum dipole field and OG model, at an inclination angle alpha equals 78 plus or minus 1 degree and observer angle zeta equals 69 plus 2 degrees or minus 1 degree. For this B-field, the TPC model is statistically disfavored compared to the OG model. For the static dipole field, neither model is significantly preferred. We found that smaller values of epsilon are favored for the offset-PC dipole field when assuming constant emissivity, and larger epsilon values favored for variable emissivity, but not significantly so. When multiplying the SG E-field by a factor of 100, we found improved light curve fits, with alpha and zeta being closer to best fits from independent studies, as well as curvature radiation reaction at lower altitudes.

Exploitation of novel gum Prunus cerasoides as mucoadhesive beads for a controlled-release drug delivery.

PubMed

Seelan, T Veenus; Kumari, Henry Linda Jeeva; Kishore, Narra; Selvamani, Palanisamy; Lalhlenmawia, H; Thanzami, K; Pachuau, Lalduhsanga; Ruckmani, Kandasamy

2016-04-01

The present study deals with the formulation of pH-sensitive mucoadhesive beads using natural gum isolated from Prunus cerasoides (PC) in combination with sodium alginate (SA) for the controlled release of diclofenac sodium (DS). PC and SA composite (PC-SA), DS loaded SA (DS-SA) and DS loaded PC-SA (DS-PC-SA) beads were prepared by ionotropic gelation method. The absence of interaction between DS and PC-SA was shown by FTIR, DSC and TGA analyses. The optimized DS-PC-SA formulation exhibited mucoadhesive property and the controlled release of DS was achieved 68% in 12h. The in vitro release kinetics follows zero order with anomalous diffusion mechanism. Therefore, the formulated mucoadhesive beads with the novel gum are preferable for the controlled release of DS by prolonging the residence time of the drug in the gastrointestinal tract, overcoming the problems associated with the immediate release dosage forms of DS. Copyright © 2016 Elsevier B.V. All rights reserved.

Dietary inflammatory index and prostate cancer risk in a case-control study in Mexico.

PubMed

Vázquez-Salas, Ruth A; Shivappa, Nitin; Galván-Portillo, Marcia; López-Carrillo, Lizbeth; Hébert, James R; Torres-Sánchez, Luisa

2016-12-01

Recent evidence suggests that a pro-inflammatory diet could be associated with prostate cancer (PC) risk. To evaluate the association between dietary inflammatory index (DII) and PC risk as well as aggressiveness, we conducted a case-control study in Mexico City. Cases were 394 individuals with incident, histologically confirmed PC, who were matched by age (±5 years) with 794 population controls. Dietary information was obtained through a semi-quantitative FFQ with a 3-year frame of reference before diagnosis, for cases, or interview, for controls. On the basis of twenty-eight food parameters, we estimated the energy-adjusted DII (E-DII). According to the Gleason score at diagnosis, PC cases were categorised as high (≥8), moderate (=7) and low (≤6) PC risk. Independent, unconditional logistic regression models adjusted for potential confounders were used to estimate PC risk and PC aggressiveness. There were no significant associations between overall PC risk and E-DII (OR3rd v. 1st tertile 1·18; 95 % CI 0·85, 1·63; P=0·33) or among men with high-risk PC (Gleason≥8) (OR 1·46; 95 % CI 0·88, 2·42; P=0·14). These results do not support the hypothesis that a pro-inflammatory diet is related to PC risk and PC aggressiveness. However, further studies with larger sample sizes, with sufficient statistical power and of varying designs should be conducted to address this hypothesis.

Association of Caveolin-1 and -2 Genetic Variants and Post-treatment Serum Caveolin-1 with Prostate Cancer Risk and Outcomes

PubMed Central

Langeberg, Wendy J.; Tahir, Salahaldin A.; Feng, Ziding; Kwon, Erika M.; Ostrander, Elaine A.; Thompson, Timothy C.; Stanford, Janet L.

2010-01-01

Background Caveolin-1 (cav-1) is overexpressed by metastatic prostate cancer (PC) cells. Pre-operative serum cav-1 levels have been shown to be a prognostic marker for PC recurrence. This study evaluated the relationship between post-treatment serum cav-1 levels and single nucleotide polymorphisms (SNPs) in the cav-1 and -2 genes with risk of PC, aggressive PC, PC recurrence or death. Methods Two case-control studies of PC among men in Washington State were combined for this analysis. Cases (n=1,458) were diagnosed in 1993–96 or 2002–05 and identified via a SEER cancer registry. Age-matched controls (n=1,351) were identified via random digit dialing. Logistic regression assessed the relationship between exposures (19 haplotype-tagging SNPs from all subjects and post-treatment serum cav-1 levels from a sample of 202 cases and 226 controls) and PC risk and aggressive PC. Cox proportional hazards regression assessed the relationship between exposures and PC recurrence and death. Results Rs9920 in cav-1 was associated with an increased relative risk of overall PC (ORCT+CC=1.37, 95%CI=1.12, 1.68) and aggressive PC (ORCT+CC=1.57, 95%CI=1.20, 2.06), but not with PC recurrence or death. High post-treatment serum cav-1 levels were not associated with PC risk, aggressive PC, or PC-specific death, but approached a significant inverse association with PC recurrence (hazard ratio=0.69, 95%CI=0.47, 1.00). Conclusions We found modest evidence for an association with a variant in the cav-1 gene and risk of overall PC and aggressive PC, which merits further study. We found no evidence that higher post-treatment serum cav-1 is associated with risk of aggressive PC or adverse PC outcomes. PMID:20209490

Laboratory process control using natural language commands from a personal computer

NASA Technical Reports Server (NTRS)

Will, Herbert A.; Mackin, Michael A.

1989-01-01

PC software is described which provides flexible natural language process control capability with an IBM PC or compatible machine. Hardware requirements include the PC, and suitable hardware interfaces to all controlled devices. Software required includes the Microsoft Disk Operating System (MS-DOS) operating system, a PC-based FORTRAN-77 compiler, and user-written device drivers. Instructions for use of the software are given as well as a description of an application of the system.

Pulsating midmorning auroral arcs, filamentation of a mixing region in a flank boundary layer, and ULF waves observed during a Polar-Svalbard conjunction

NASA Astrophysics Data System (ADS)

Farrugia, C. J.; Sandholt, P. E.; Maynard, N. C.; Burke, W. J.; Scudder, J. D.; Ober, D. M.; Moen, J.; Russell, C. T.

2000-12-01

Magnetically conjugate observations by the HYDRA and the Magnetic Field Experiment instruments on Polar, meridian-scanning photometers and all-sky imagers at Ny-Ålesund, and International Monitor for Auroral Geomagnetic Effects (IMAGE) magnetometers on November 30, 1997, illustrate aspects of magnetosphere-ionosphere coupling at 0900-1000 magnetic local times (MLT) and 70°-80° magnetic latitudes and their dependence on interplanetary parameters. Initially, Polar crossed a boundary layer on closed field lines where magnetospheric and magnetosheath plasmas are mixed. This region contains filaments where magnetospheric electron and ion fluxes are enhanced. These filaments are associated with field-aligned current structures embedded within the large-scale region 1 (R1) current. Ground auroral imagery document the presence at this time of discrete, east-west aligned arcs, which are in one-to-one correspondence with the filaments. Temporal variations present in these auroral arcs correlate with Pc 5 pulsations and are probably related to modulations in the interplanetary electric field. The auroral observations indicate that the filamented mixing region persisted for many tens of minutes, suggesting a spatial structuring. The data suggest further that the filamented, mixing region is an important source of the R1 current and the associated midmorning arcs. When the interplanetary magnetic field (IMF) turned strongly north, Polar had entered the dayside extension of the central plasma sheet/region 2 current system where it and the underlying ground magnetometers recorded a clear field line resonance of frequency ~2.4 mHz (Pc 5 range). The source of these oscillations is most likely the Kelvin-Helmholtz instability. Subsequent to the IMF northward turning, the multiple arcs were replaced by a single auroral form to the north of Ny-Ålesund (at 1000 MLT) in the vicinity of the westward edge of the cusp. ULF pulsation activity changed to the Pc 3-4 range in the regime of the pulsating diffuse aurora when the IMF went to an approximately Parker spiral orientation and the ground stations had rotated into the MLT sector of cusp emissions.

Platelet count and platelet indices in women with preeclampsia.

PubMed

AlSheeha, Muneera A; Alaboudi, Rafi S; Alghasham, Mohammad A; Iqbal, Javed; Adam, Ishag

2016-01-01

Although the exact pathophysiology of preeclampsia is not completely understood, the utility of different platelets indices can be utilized to predict preeclampsia. To compare platelet indices, namely platelet count (PC), mean platelet volume (MPV), platelet distribution width (PDW), and PC to MPV ratio in women with preeclampsia compared with healthy controls. Qassim Hospital, Kingdom of Saudi Arabia. A case-control study. Sixty preeclamptic women were the cases and an equal number of healthy pregnant women were the controls. There was no significant difference in age, parity, and body mass index between the study groups. Sixteen and 44 of the cases were severe and mild preeclampsia, respectively. There was no significant difference in PDW and MPV between the preeclamptic and control women. Both PC and PC to MPV ratios were significantly lower in the women with preeclampsia compared with the controls. There was no significant difference in the PC, PDW, MPV, and PC to MPV ratio when women with mild and severe preeclampsia were compared. Using receiver operating characteristic (ROC) curves, the PC cutoff was 248.0×10 3 /µL for diagnosis of pre-eclampsia ( P =0.019; the area under the ROC curve was 62.4%). Binary regression suggests that women with PC <248.010×10 3 /µL were at higher risk of preeclampsia (odds ratio =2.2, 95% confidence interval =1.08-4.6, P =0.03). The PC/MPV cutoff was 31.2 for diagnosis of preeclampsia ( P =0.035, the area under the ROC curve was 62.2%). PC <248.010×10 3 /µL and PC to MPV ratio 31.2 are valid predictors of preeclampsia.

Subphthalocyanines Axially Substituted with a Tetracyanobuta-1,3-diene-Aniline Moiety: Synthesis, Structure, and Physicochemical Properties.

PubMed

Winterfeld, Kim A; Lavarda, Giulia; Guilleme, Julia; Sekita, Michael; Guldi, Dirk M; Torres, Tomás; Bottari, Giovanni

2017-04-19

A 1,1,4,4-tetracyanobuta-1,3-diene (TCBD)-aniline moiety has been introduced, for the first time, at the axial position of two subphthalocyanines (SubPcs) peripherally substituted with hydrogen (H 12 SubPc) or fluorine atoms (F 12 SubPc). Single-crystal X-ray analysis of both SubPc-TCBD-aniline systems showed that each conjugate is a racemic mixture of two atropisomers resulting from the almost orthogonal geometry adopted by the axial TCBD unit, which were separated by chiral high-performance liquid chromatography. Remarkably, the single-crystal X-ray structure of one atropisomer of each SubPc-TCBD-aniline conjugate has been solved, allowing to unambiguously assign the atropisomers' absolute configuration, something, to the best of our knowledge, unprecedented in TCBD-based conjugates. Moreover, the physicochemical properties of both SubPc-TCBD-aniline racemates have been investigated using a wide range of electrochemical as well as steady-state and time-resolved spectroscopic techniques. Each of the two SubPc-TCBD-aniline conjugates presents a unique photophysical feature never observed before in SubPc chemistry. As a matter of fact, H 12 SubPc-TCBD-aniline showed significant ground-state charge transfer interactions between the H 12 SubPc macrocycle and the electron-withdrawing TCBD unit directly attached at its axial position. In contrast, F 12 SubPc-TCBD-aniline gave rise to an intense, broad emission, which red shifts upon increasing the solvent polarity and stems from an excited complex (i.e., an exciplex). Such an exciplex emission, which has also no precedent in TCBD chemistry, results from intramolecular interactions in the excited state between the electron-rich aniline and the F 12 SubPc π-surface, two molecular fragments kept in spatial proximity by the "unique" three-dimensional geometry adopted by the F 12 SubPc-TCBD-aniline. Complementary transient absorption studies were carried out on both SubPc-TCBD-aniline derivatives, showing the occurrence, in both cases, of photoinduced charge separation and corroborating the formation of the aforementioned intramolecular exciplex in terms of a radical ion pair stabilized through-space.

New Insights into the Electroreduction of Ethylene Sulfite as Electrolyte Additive for Facilitating Solid Electrolyte Interphase of Lithium Ion Battery

PubMed Central

Sun, Youmin; Wang, Yixuan

2017-01-01

To help understand the solid electrolyte interphase (SEI) formation facilitated by electrolyte additives of lithium-ion batteries (LIB) the supermolecular clusters [(ES)Li+(PC)m](PC)n (m=1–2; n=0, 6, and 9) were used to investigate the electroreductive decompositions of the electrolyte additive, ethylene sulfite (ES), as well as the solvent, propylene carbonate (PC) with density functional theory. The results show that ES can be reduced prior to PC, resulting in a reduction precursor that will then undergo a ring opening decomposition to yield a radical anion. A new concerted pathway (path B) was located for the ring opening of the reduced ES, which has much lower energy barrier than the previously reported stepwise pathway (path A). The transition state for the ring opening of PC induced by the reduced ES (path C, indirect path) is closer to that of path A than path B in energy. The direct ring opening of the reduced PC (path D) has lower energy barrier than those of paths A, B and C, yet it is less favorable than the latter paths in terms of thermodynamics (vertical electron affinity or the reduction potential dissociation energy). The overall rate constant including the initial reduction and the subsequent ring opening for path B is the largest among the four paths, followed by paths A>C>D, which further signifies the importance of the concerted new path in facilitating the SEI. The hybrid models, the supermolecular cluster augmented by polarized continuum model, PCM-[(ES)Li+(PC)2](PC)n (n=0,6, and 9), were used to further estimate the reduction potential by taking into account both explicit and implicit solvent effects. The second solvation shell of Li+ in [(ES)Li+(PC)2](PC)n (n=6, and 9) partially compensates the overestimation of solvent effects arising from the PCM model for the naked (ES)Li+(PC)2, and the theoretical reduction potential with PCM-[(ES)Li+(PC)2](PC)6 (1.90–1.93V) agrees very well with the experimental one (1.8–2.0V). PMID:28220165

New insights into the electroreduction of ethylene sulfite as an electrolyte additive for facilitating solid electrolyte interphase formation in lithium ion batteries.

PubMed

Sun, Youmin; Wang, Yixuan

2017-03-01

To help understand the solid electrolyte interphase (SEI) formation facilitated by electrolyte additives of lithium-ion batteries (LIBs) the supermolecular clusters [(ES)Li + (PC) m ](PC) n (m = 1-2; n = 0, 6 and 9) were used to investigate the electroreductive decompositions of the electrolyte additive ethylene sulfite (ES) as well as the solvent propylene carbonate (PC) with density functional theory. The results show that ES can be reduced prior to PC, resulting in a reduction precursor that will then undergo a ring opening decomposition to yield a radical anion. A new concerted pathway (path B) was located for the ring opening of the reduced ES, which has a much lower energy barrier than the previously reported stepwise pathway (path A). The transition state for the ring opening of PC induced by the reduced ES (path C, indirect path) is closer to that of path A than path B in energy. The direct ring opening of the reduced PC (path D) has a lower energy barrier than paths A, B and C, yet it is less favorable than the latter paths in terms of thermodynamics (vertical electron affinity or reduction potential and dissociation energy). The overall rate constant including the initial reduction and the subsequent ring opening for path B is the largest among the four paths, followed by paths A > C > D, which further signifies the importance of the concerted new path in facilitating the SEI formation. The hybrid models, the supermolecular clusters augmented by a polarized continuum model, PCM-[(ES)Li + (PC) 2 ](PC) n (n = 0, 6 and 9), were used to further estimate the reduction potential by taking into account both explicit and implicit solvent effects. The second solvation shell of Li + in [(ES)Li + (PC) 2 ](PC) n (n = 6 and 9) partially compensates the overestimation of solvent effects arising from the PCM for the naked (ES)Li + (PC) 2 , and the theoretical reduction potential of PCM-[(ES)Li + (PC) 2 ](PC) 6 (1.90-1.93 V) agrees very well with the experimental one (1.8-2.0 V).

Extended High Circular Polarization in the Orion Massive Star Forming Region: Implications for the Origin of Homochirality in the Solar System

PubMed Central

Tamura, Motohide; Kandori, Ryo; Kusakabe, Nobuhiko; Hough, James H.; Bailey, Jeremy; Whittet, Douglas C. B.; Lucas, Philip W.; Nakajima, Yasushi; Hashimoto, Jun

2010-01-01

We present a wide-field (∼6′ × 6′) and deep near-infrared (Ks band: 2.14 μm) circular polarization image in the Orion nebula, where massive stars and many low-mass stars are forming. Our results reveal that a high circular polarization region is spatially extended (∼0.4 pc) around the massive star-forming region, the BN/KL nebula. However, other regions, including the linearly polarized Orion bar, show no significant circular polarization. Most of the low-mass young stars do not show detectable extended structure in either linear or circular polarization, in contrast to the BN/KL nebula. If our solar system formed in a massive star-forming region and was irradiated by net circularly polarized radiation, then enantiomeric excesses could have been induced, through asymmetric photochemistry, in the parent bodies of the meteorites and subsequently delivered to Earth. These could then have played a role in the development of biological homochirality on Earth. PMID:20213160

Temperature Dependent Electrical Properties of PZT Wafer

NASA Astrophysics Data System (ADS)

Basu, T.; Sen, S.; Seal, A.; Sen, A.

2016-04-01

The electrical and electromechanical properties of lead zirconate titanate (PZT) wafers were investigated and compared with PZT bulk. PZT wafers were prepared by tape casting technique. The transition temperature of both the PZT forms remained the same. The transition from an asymmetric to a symmetric shape was observed for PZT wafers at higher temperature. The piezoelectric coefficient (d 33) values obtained were 560 pc/N and 234 pc/N, and the electromechanical coupling coefficient (k p) values were 0.68 and 0.49 for bulk and wafer, respectively. The reduction in polarization after fatigue was only ~3% in case of PZT bulk and ~7% for PZT wafer.

Efficient spin-filter and negative differential resistance behaviors in FeN4 embedded graphene nanoribbon device

NASA Astrophysics Data System (ADS)

Liu, N.; Liu, J. B.; Yao, K. L.; Ni, Y.; Wang, S. L.

2016-03-01

In this paper, we propose a new device of spintronics by embedding two FeN4 molecules into armchair graphene nanoribbon and sandwiching them between N-doped graphene nanoribbon electrodes. Our first-principle quantum transport calculations show that the device is a perfect spin filter with high spin-polarizations both in parallel configuration (PC) and antiparallel configuration (APC). Moreover, negative differential resistance phenomena are obtained for the spin-down current in PC, and the spin-up and spin-down currents in APC. These transport properties are explained by the bias-dependent evolution of molecular orbitals and the transmission spectra.

Do lipids retard the evaporation of the tear fluid?

PubMed

Rantamäki, Antti H; Javanainen, Matti; Vattulainen, Ilpo; Holopainen, Juha M

2012-09-21

We examined in vitro the potential evaporation-retarding effect of the tear film lipid layer (TFLL). The artificial TFLL compositions used here were based on the present knowledge of TFLL composition. A custom-built system was developed to measure evaporation rates at 35°C. Lipids were applied to an air-water interface, and the evaporation rate through the lipid layer was defined as water loss from the interface. A thick layer of olive oil and a monolayer of long-chain alcohol were used as controls. The artificial TFLLs were composed of 1 to 4 lipid species: polar phosphatidylcholine (PC), nonpolar cholesteryl ester, triglycerides, and wax ester (WE). Brewster angle microscopy (BAM) and interfacial shear rheometry (ISR) were used to assess the lateral structure and shear stress response of the lipid layers, respectively. Olive oil and long-chain alcohol decreased evaporation by 54% and 45%, respectively. The PC monolayer and the four-component mixtures did not retard evaporation. WE was the most important evaporation-retardant TFLL lipid (∼20% decrease). In PC/WE mixtures, an ∼90% proportion of WE was required for evaporation retardation. Based on BAM and ISR, WE resulted in more condensed layers than the non-retardant layers. Highly condensed, solid-like lipid layers, such as those containing high proportions of WEs, are evaporation-retardant. In multi-component lipid layers, the evaporation-retardant interactions between carbon chains decrease and, therefore, these lipid layers do not retard evaporation.

The displacement of the sun from the galactic plane using IRAS and faust source counts

NASA Technical Reports Server (NTRS)

Cohen, Martin

1995-01-01

I determine the displacement of the Sun from the Galactic plane by interpreting IRAS point-source counts at 12 and 25 microns in the Galactic polar caps using the latest version of the SKY model for the point-source sky (Cohen 1994). A value of solar zenith = 15.5 +/- 0.7 pc north of the plane provides the best match to the ensemble of useful IRAS data. Shallow K counts in the north Galactic pole are also best fitted by this offset, while limited FAUST far-ultraviolet counts at 1660 A near the same pole favor a value near 14 pc. Combining the many IRAS determinations with the few FAUST values suggests that a value of solar zenith = 15.0 +/- 0.5 pc (internal error only) would satisfy these high-latitude sets of data in both wavelength regimes, within the context of the SKY model.

Cluster observations of EMIC triggered emissions in association with Pc1 waves near Earth's plasmapause

NASA Astrophysics Data System (ADS)

Pickett, J. S.; Grison, B.; Omura, Y.; Engebretson, M. J.; Dandouras, I.; Masson, A.; Adrian, M. L.; Santolík, O.; Décréau, P. M. E.; Cornilleau-Wehrlin, N.; Constantinescu, D.

2010-05-01

The Cluster spacecraft were favorably positioned on the nightside near the equatorial plasmapause of Earth at L ˜ 4.3 on 30 March 2002 to observe electromagnetic ion cyclotron (EMIC) rising tone emissions in association with Pc1 waves at 1.5 Hz. The EMIC rising tone emissions were found to be left-hand, circularly polarized, dispersive, and propagating away from the equator. Their burstiness and dispersion of ˜30s/Hz rising out of the 1.5 Hz Pc1 waves are consistent with their identification as EMIC triggered chorus emissions, the first to be reported through in situ observations near the plasmapause. Along with the expected H+ ring current ions seen at higher energies (>300 eV), lower energy ions (300 eV and less) were observed during the most intense EMIC triggered emission events. Nonlinear wave-particle interactions via cyclotron resonance between the ˜2-10 keV H+ ions with temperature anisotropy and the linearly-amplified Pc1 waves are suggested as a possible generation mechanism for the EMIC triggered emissions.

Cerebellar pathology in childhood-onset vs. adult-onset essential tremor.

PubMed

Louis, Elan D; Kuo, Sheng-Han; Tate, William J; Kelly, Geoffrey C; Faust, Phyllis L

2017-10-17

Although the incidence of ET increases with advancing age, the disease may begin at any age, including childhood. The question arises as to whether childhood-onset ET cases manifest the same sets of pathological changes in the cerebellum as those whose onset is during adult life. We quantified a broad range of postmortem features (Purkinje cell [PC] counts, PC axonal torpedoes, a host of associated axonal changes [PC axonal recurrent collateral count, PC thickened axonal profile count, PC axonal branching count], heterotopic PCs, and basket cell rating) in 60 ET cases (11 childhood-onset and 49 adult-onset) and 30 controls. Compared to controls, childhood-onset ET cases had lower PC counts, higher torpedo counts, higher heterotopic PC counts, higher basket cell plexus rating, and marginally higher PC axonal recurrent collateral counts. The median PC thickened axonal profile count and median PC axonal branching count were two to five times higher in childhood-onset ET than controls, but the differences did not reach statistical significance. Childhood-onset and adult-onset ET had similar PC counts, torpedo counts, heterotopic PC counts, basket cell plexus rating, PC axonal recurrent collateral counts, PC thickened axonal profile count and PC axonal branching count. In conclusion, we found that childhood-onset and adult-onset ET shared similar pathological changes in the cerebellum. The data suggest that pathological changes we have observed in the cerebellum in ET are a part of the pathophysiological cascade of events in both forms of the disease and that both groups seem to reach the same pathological endpoints at a similar age of death. Copyright © 2017 Elsevier B.V. All rights reserved.

Lipid class and fatty acid composition of a little-known and rarely collected alga Exophyllum wentii Weber-van Bosse from Bali Island, Indonesia.

PubMed

Illijas, Muhammad I; Indy, Jeane R; Yasui, Hajime; Itabashi, Yutaka

2009-01-01

The lipid class and fatty acid composition of a little-known and rarely collected alga Exophyllum wentii from Bali Island, Indonesia were determined for fresh and frozen-thawed samples using thin-layer chromatography, gas-liquid chromatography, and high-performance liquid chromatography. Glycoglycerolipids, which mainly consisted of mongalactosyldiacylglycerols (MGDG) and digalactosyldiacylglycerols (DGDG), were the predominant lipid components, accounting for 67% and 56% of the total polar lipid content in the fresh and frozen-thawed samples, respectively. Phospholipids, including phosphatidylcholines (PC) and phosphatidylglycerols (PG), were detected with lesser amounts in both samples (16-17% of the total polar lipid content). Free fatty acids (FFA), sterols and triacylglycerols (TAG) were also detected in minor quantities; however, the FFA content in the frozen-thawed sample increased to up to 20% of the total lipid content, suggesting that hydrolysis of the membrane lipids had occurred. A crude enzyme preparation from the alga showed activities for hydrolyzing the acyl groups of the phospholipids and glycoglycerolipids. Palmitic acid (16:0) and arachidonic acid (20:4n-6) were the major fatty acids in both the total lipid and in individual polar lipid classes as well as the dominant fatty acids released from the membrane lipids by enzymatic hydrolysis. The high level of 20:4n-6 (29%) in the total lipid and the presence of considerable amounts of PC (11% of the total polar lipid) and PG (6.2%) support classification of E. wentii into the Division Rhodophyta.

pH-Cleavable Nucleoside Lipids: A New Paradigm for Controlling the Stability of Lipid-Based Delivery Systems.

PubMed

Oumzil, Khalid; Benizri, Sébastien; Tonelli, Giovanni; Staedel, Cathy; Appavoo, Ananda; Chaffanet, Max; Navailles, Laurence; Barthélémy, Philippe

2015-11-01

Lipid-based delivery systems are an established technology with considerable clinical acceptance and several applications in human. Herein, we report the design, synthesis and evaluation of novel orthoester nucleoside lipids (ONLs) for the modulation of liposome stability. The ONLs contain head groups with 3'-orthoester nucleoside derivatives featuring positive or negative charges. The insertion of the orthoester function in the NL structures allows the formation of pH-sensitive liposomes. ONL-based liposomes can be hydrolyzed to provide nontoxic products, including nucleoside derivatives and hexadecanol. To allow the release to be tunable at different hydrolysis rates, the charge of the polar head structure is modulated, and the head group can be released at a biologically relevant pH. Crucially, when ONLs are mixed with natural phosphocholine lipids (PC), the resultant liposome evolves toward the formation of a hexadecanol/PC lamellar system. Biological evaluation shows that stable nucleic acid lipid particles (SNALPs) formulated with ONLs and siRNAs can effectively enter into tumor cells and release their nucleic acid payload in response to an intracellular acidic environment. This results in a much higher antitumor activity than conventional SNALPs. The ability to use pH-cleavable nucleolipids to control the stability of lipid-based delivery systems represents a promising approach for the intracellular delivery of drug cargos. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Magnetic substorms and northward IMF turning

NASA Astrophysics Data System (ADS)

Troshichev, Oleg; Podorozhkina, Nataly

To determine the relation of the northward IMF turnings to substorm sudden onsets, we separated all events with sharp northward IMF turnings observed in years of solar maximum (1999-2002) and solar minimum (2007-2008). The events (N=261) have been classified in 5 groups in accordance with average magnetic activity in auroral zone (low, moderate or high levels of AL index) at unchanged or slightly changed PC index and with dynamics of PC (steady distinct growth or distinct decline) at arbitrary values of AL index. Statistical analysis of relationships between the IMF turning and changes of PC and AL indices has been fulfilled separately for each of 5 classes. Results of the analysis showed that, irrespective of geophysical conditions and solar activity epoch, the magnetic activity in the polar caps and in the auroral zone demonstrate no response to the sudden northward IMF turning, if the moment of northward turning is taken as a key date. Sharp increases of magnetic disturbance in the auroral zone are observed only under conditions of the growing PC index and statistically they are related to moment of the PC index exceeding the threshold level (~1.5 mV/m), not to northward turnings timed, as a rule, after the moment of sudden onset. Magnetic disturbances observed in these cases in the auroral zone (magnetic substorms) are guided by behavior of the PC index, like to ordinary magnetic substorms or substorms developed under conditions of the prolonged northward IMF impact on the magnetosphere. The evident inconsistency between the sharp IMF changes measured outside of the magnetosphere and behavior of the ground-based PC index, the latter determining the substorm development, provides an additional argument in favor of the PC index as a ground-based proxy of the solar wind energy that entered into magnetosphere.

An important rule for realizing metal → half-metal → semiconductor transition in single-molecule junctions

NASA Astrophysics Data System (ADS)

Zeng, Jing; Chen, Ke-Qiu; Long, Mengqiu

2017-06-01

Recently, Zhong et al (2015 Nano Lett. 15 8091) found that two additional hydrogen atoms can be adsorbed to the opposite aza-bridging nitrogen atoms of the manganese phthalocyanine (MnPc) macrocycle when exposed to H2. Thus the symmetry of the MnPc molecule is changed from 4-fold to 2-fold. Motivated by this recent experiment, we theoretically investigate a MnPc-based single-molecule junction in this work and propose a simple and reliable way to realize the transition of its electronic properties. On the basis of spin-polarized density-functional theory calculations combined with the Keldysh nonequilibrium Green’s technique, we find that the gradual hydrogenation in MnPc molecules gives rise to the changes of the hardness of the electron density and spin-selective orbital decoupling, which eventually leads to the realization of the first ever metal  →  half-metal  →  semiconductor transition behavior in single-molecule junctions. Analysis of molecular projected self-consistent Hamiltonian, Mulliken population, and local density of states also reveals an important rule for realizing this transition behavior. Our research confirms that the hydrogenation of MnPc molecules can realize various molecular functionalities in unitary material background.

Surface modification of a biodegradable magnesium alloy with phosphorylcholine (PC) and sulfobetaine (SB) functional macromolecules for reduced thrombogenicity and acute corrosion resistance.

PubMed

Ye, Sang-Ho; Jang, Yong-Seok; Yun, Yeo-Heung; Shankarraman, Venkat; Woolley, Joshua R; Hong, Yi; Gamble, Lara J; Ishihara, Kazuhiko; Wagner, William R

2013-07-02

Siloxane functionalized phosphorylcholine (PC) or sulfobetaine (SB) macromolecules (PCSSi or SBSSi) were synthesized to act as surface modifying agents for degradable metallic surfaces to improve acute blood compatibility and slow initial corrosion rates. The macromolecules were synthesized using a thiol-ene radical photopolymerization technique and then utilized to modify magnesium (Mg) alloy (AZ31) surfaces via an anhydrous phase deposition of the silane functional groups. X-ray photoelectron spectroscopy surface analysis results indicated successful surface modification based on increased nitrogen and phosphorus or sulfur composition on the modified surfaces relative to unmodified AZ31. In vitro acute thrombogenicity assessment after ovine blood contact with the PCSSi and SBSSi modified surfaces showed a significant decrease in platelet deposition and bulk phase platelet activation compared with the control alloy surfaces. Potentiodynamic polarization and electrochemical impedance spectroscopy data obtained from electrochemical corrosion testing demonstrated increased corrosion resistance for PCSSi- and SBSSi-modified AZ31 versus unmodified surfaces. The developed coating technique using PCSSi or SBSSi showed promise in acutely reducing both the corrosion and thrombotic processes, which would be attractive for application to blood contacting devices, such as vascular stents, made from degradable Mg alloys.

Limitations of Electromagnetic Ion Cyclotron Wave Observations in Low Earth Orbit

NASA Astrophysics Data System (ADS)

Hwang, Junga; Kim, Hyangpyo; Park, Jaeheung; Lee, Jaejin

2018-03-01

Pc1 pulsations are geomagnetic fluctuations in the frequency range of 0.2 to 5 Hz. There have been several observations of Pc1 pulsations in low earth orbit by MAGSAT, DE-2, Viking, Freja, CHAMP, and SWARM satellites. However, there has been a clear limitation in resolving the spatial and temporal variations of the pulsation by using a single-point observation by a single satellite. To overcome such limitations of previous observations, a new space mission was recently initiated, using the concept of multi-satellites, named the Small scale magNetospheric and Ionospheric Plasma Experiments (SNIPE). The SNIPE mission consists of four nanosatellites ( 10 kg), which will be launched into a polar orbit at an altitude of 600 km (TBD) in 2020. Four satellites will be deployed in orbit, and the distances between each satellite will be controlled from 10 to 1,000 km by a highend formation-flying algorithm. One of the possible science targets of the SNIPE mission is observing electromagnetic ion cyclotron (EMIC) waves. In this paper, we report on examples of observations, showing the limitations of previous EMIC observations in low earth orbit, and suggest possibilities to overcome those limitations through a new mission.

Some Phthalocyanine and Naphthalocyanine Derivatives as Corrosion Inhibitors for Aluminium in Acidic Medium: Experimental, Quantum Chemical Calculations, QSAR Studies and Synergistic Effect of Iodide Ions.

PubMed

Dibetsoe, Masego; Olasunkanmi, Lukman O; Fayemi, Omolola E; Yesudass, Sasikumar; Ramaganthan, Baskar; Bahadur, Indra; Adekunle, Abolanle S; Kabanda, Mwadham M; Ebenso, Eno E

2015-08-28

The effects of seven macrocyclic compounds comprising four phthalocyanines (Pcs) namely 1,4,8,11,15,18,22,25-octabutoxy-29H,31H-phthalocyanine (Pc1), 2,3,9,10,16,17,23,24-octakis(octyloxy)-29H,31H-phthalocyanine (Pc2), 2,9,16,23-tetra-tert-butyl-29H,31H-phthalocyanine (Pc3) and 29H,31H-phthalocyanine (Pc4), and three naphthalocyanines namely 5,9,14,18,23,27,32,36-octabutoxy-2,3-naphthalocyanine (nPc1), 2,11,20,29-tetra-tert-butyl-2,3-naphthalocyanine (nPc2) and 2,3-naphthalocyanine (nP3) were investigated on the corrosion of aluminium (Al) in 1 M HCl using a gravimetric method, potentiodynamic polarization technique, quantum chemical calculations and quantitative structure activity relationship (QSAR). Synergistic effects of KI on the corrosion inhibition properties of the compounds were also investigated. All the studied compounds showed appreciable inhibition efficiencies, which decrease with increasing temperature from 30 °C to 70 °C. At each concentration of the inhibitor, addition of 0.1% KI increased the inhibition efficiency compared to the absence of KI indicating the occurrence of synergistic interactions between the studied molecules and I(-) ions. From the potentiodynamic polarization studies, the studied Pcs and nPcs are mixed type corrosion inhibitors both without and with addition of KI. The adsorption of the studied molecules on Al surface obeys the Langmuir adsorption isotherm, while the thermodynamic and kinetic parameters revealed that the adsorption of the studied compounds on Al surface is spontaneous and involves competitive physisorption and chemisorption mechanisms. The experimental results revealed the aggregated interactions between the inhibitor molecules and the results further indicated that the peripheral groups on the compounds affect these interactions. The calculated quantum chemical parameters and the QSAR results revealed the possibility of strong interactions between the studied inhibitors and metal surface. QSAR analysis on the quantum chemical parameters obtained with B3LYP/6-31G (d,p) method show that a combination of two quantum chemical parameters to form a composite index provides the best correlation with the experimental data.

Parallel artificial liquid membrane extraction as an efficient tool for removal of phospholipids from human plasma.

PubMed

Ask, Kristine Skoglund; Bardakci, Turgay; Parmer, Marthe Petrine; Halvorsen, Trine Grønhaug; Øiestad, Elisabeth Leere; Pedersen-Bjergaard, Stig; Gjelstad, Astrid

2016-09-10

Generic Parallel Artificial Liquid Membrane Extraction (PALME) methods for non-polar basic and non-polar acidic drugs from human plasma were investigated with respect to phospholipid removal. In both cases, extractions in 96-well format were performed from plasma (125μL), through 4μL organic solvent used as supported liquid membranes (SLMs), and into 50μL aqueous acceptor solutions. The acceptor solutions were subsequently analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) using in-source fragmentation and monitoring the m/z 184→184 transition for investigation of phosphatidylcholines (PC), sphingomyelins (SM), and lysophosphatidylcholines (Lyso-PC). In both generic methods, no phospholipids were detected in the acceptor solutions. Thus, PALME appeared to be highly efficient for phospholipid removal. To further support this, qualitative (post-column infusion) and quantitative matrix effects were investigated with fluoxetine, fluvoxamine, and quetiapine as model analytes. No signs of matrix effects were observed. Finally, PALME was evaluated for the aforementioned drug substances, and data were in accordance with European Medicines Agency (EMA) guidelines. Copyright © 2016 Elsevier B.V. All rights reserved.

Study of optical reflectance properties in 1D annular photonic crystal containing double negative (DNG) metamaterials

NASA Astrophysics Data System (ADS)

Srivastava, Sanjeev K.; Aghajamali, Alireza

2016-05-01

Theoretical investigation of photonic band gaps or reflection bands in one-dimensional annular photonic crystal (APC) containing double negative (DNG) metamaterials and air has been presented. The proposed structure consists of the alternate layers of dispersive DNG material and air immersed in free space. In order to study photonic band gaps we obtain the reflectance spectrum of the annular PC by employing the transfer matrix method (TMM) in the cylindrical waves for both TE and TM polarizations. In this work we study the effect of azimuthal mode number (m) and starting radius (ρ0) on the three band gaps viz. zero averaged refractive index (zero-nbar) gap, zero permittivity (zero- ε) and zero permeability (zero- μ) gaps. It is found that for m ≥ 1 , zero- μ gap appears in TE mode and zero- ε gap appears in TM mode. The width of both zero- μ and zero- ε gap increases by increasing m values, but the enhancement of zero- μ gap is more appreciable. Also, the effect of ρ0 on the three band gaps (reflection bands) of annular PC structure at the given m-number has been studied, for both TE and TM polarizations. The result shows that in both polarizations zero- ε and zero- μ gaps decreases when ρ0 increases, whereas zero-nbar gap remains invariant.

RP-HPLC method using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate incorporated with normalization technique in principal component analysis to differentiate the bovine, porcine and fish gelatins.

PubMed

Azilawati, M I; Hashim, D M; Jamilah, B; Amin, I

2015-04-01

The amino acid compositions of bovine, porcine and fish gelatin were determined by amino acid analysis using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate as derivatization reagent. Sixteen amino acids were identified with similar spectral chromatograms. Data pre-treatment via centering and transformation of data by normalization were performed to provide data that are more suitable for analysis and easier to be interpreted. Principal component analysis (PCA) transformed the original data matrix into a number of principal components (PCs). Three principal components (PCs) described 96.5% of the total variance, and 2 PCs (91%) explained the highest variances. The PCA model demonstrated the relationships among amino acids in the correlation loadings plot to the group of gelatins in the scores plot. Fish gelatin was correlated to threonine, serine and methionine on the positive side of PC1; bovine gelatin was correlated to the non-polar side chains amino acids that were proline, hydroxyproline, leucine, isoleucine and valine on the negative side of PC1 and porcine gelatin was correlated to the polar side chains amino acids that were aspartate, glutamic acid, lysine and tyrosine on the negative side of PC2. Verification on the database using 12 samples from commercial products gelatin-based had confirmed the grouping patterns and the variables correlations. Therefore, this quantitative method is very useful as a screening method to determine gelatin from various sources. Copyright © 2014 Elsevier Ltd. All rights reserved.

KSC-98pc1210

NASA Image and Video Library

1998-10-02

KENNEDY SPACE CENTER, FLA. -- The Mars Polar Lander is uncrated in the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2). The Mars Polar Lander is targeted for launch from Cape Canaveral Air Station aboard a Delta II rocket on Jan. 3, 1999. The solar-powered spacecraft is designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere

KSC-98pc1212

NASA Image and Video Library

1998-10-02

KENNEDY SPACE CENTER, FLA. -- The Mars Polar Lander awaits testing in the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2). The Mars Polar Lander is targeted for launch from Cape Canaveral Air Station aboard a Delta II rocket on Jan. 3, 1999. The solar-powered spacecraft is designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere

Matrix effects on copper(II)phthalocyanine complexes. A combined continuous wave and pulse EPR and DFT study.

PubMed

Finazzo, Cinzia; Calle, Carlos; Stoll, Stefan; Van Doorslaer, Sabine; Schweiger, Arthur

2006-04-28

The effect of the electron withdrawing or donating character of groups located at the periphery of the phthalocyanine ligand, as well as the influence of polar and nonpolar solvents are of importance for the redox chemistry of metal phthalocyanines. Continuous wave and pulse electron paramagnetic resonance and pulse electron nuclear double resonance spectroscopy at X- and Q-band are applied to investigate the electronic structure of the complexes Cu(II)phthalocyanine (CuPc), copper(II) 2,9,16,23-tetra-tert-butyl-29H,31H-phthalocyanine (CuPc(t)), and copper(II) 1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25-hexadecafluoro-29H,31H-phthalocyanine (CuPc(F)) in various matrices. Isotope substitutions are used to determine the g values, the copper hyperfine couplings and the hyperfine interactions with the 14N, 1H and 19F nuclei of the macrocycle and the surrounding matrix molecules. Simulations and interpretations of the spectra are shown and discussed, and a qualitative analysis of the data using previous theoretical models is given. Density functional computations facilitate the interpretation of the EPR parameters. The experimental g, copper and nitrogen hyperfine and nuclear quadrupole values are found to be sensitive to changes of the solvent and the structure of the macrocycle. To elucidate the electronic, structural and bonding properties the changes in the g principal values are related to data from UV/Vis spectroscopy and to density functional theory (DFT) computations. The analysis of the EPR data indicates that the in-plane metal-ligand sigma bonding is more covalent for CuPc(t) in toluene than in sulfuric acid. Furthermore, the out-of-plane pi bonding is found to be less covalent in the case of a polar sulfuric acid environment than with nonpolar toluene or H2Pc environment, whereby the covalency of this bonding is increased upon addition of tert-butyl groups. No contribution from in-plane pi bonding is found.

Enhanced optical limiting effects in a double-decker bis(phthalocyaninato) rare earth complex using radially polarized beams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Jia-Lu; Gu, Bing, E-mail: gubing@seu.edu.cn; Liu, Dahui

2014-10-27

Optical limiting (OL) effects can be enhanced by exploiting various limiting mechanisms and by designing nonlinear optical materials. In this work, we present the large enhancement of OL effects by manipulating the polarization distribution of the light field. Theoretically, we develop the Z-scan and nonlinear transmission theories on a two-photon absorber under the excitation of cylindrical vector beams. It is shown that both the sensitivity of Z-scan technique and the OL effect using radially polarized beams have the large enhancement compared with that using linearly polarized beams (LPBs). Experimentally, we investigate the nonlinear absorption properties of a double-decker Pr[Pc(OC{sub 8}H{submore » 17}){sub 8}]{sub 2} rare earth complex by performing Z-scan measurements with femtosecond-pulsed radially polarized beams at 800 nm wavelength. The observed two-photon absorption process, which originates from strong intramolecular π–π interaction, is exploited for OL application. The results demonstrate the large enhancement of OL effects using radially polarized beams instead of LPBs.« less

Identification of Biomarkers for PKD1 Using Urinary Exosomes

PubMed Central

Hogan, Marie C.; Bakeberg, Jason L.; Gainullin, Vladimir G.; Irazabal, Maria V.; Harmon, Amber J.; Lieske, John C.; Charlesworth, M. Cristine; Johnson, Kenneth L.; Madden, Benjamin J.; Zenka, Roman M.; McCormick, Daniel J.; Sundsbak, Jamie L.; Heyer, Christina M.; Torres, Vicente E.; Harris, Peter C.

2015-01-01

Autosomal dominant polycystic kidney disease (ADPKD) is a common cause of ESRD. Affected individuals inherit a defective copy of either PKD1 or PKD2, which encode polycystin-1 (PC1) or polycystin-2 (PC2), respectively. PC1 and PC2 are secreted on urinary exosome-like vesicles (ELVs) (100-nm diameter vesicles), in which PC1 is present in a cleaved form and may be complexed with PC2. Here, label-free quantitative proteomic studies of urine ELVs in an initial discovery cohort (13 individuals with PKD1 mutations and 18 normal controls) revealed that of 2008 ELV proteins, 9 (0.32%) were expressed at significantly different levels in samples from individuals with PKD1 mutations compared to controls (P<0.03). In samples from individuals with PKD1 mutations, levels of PC1 and PC2 were reduced to 54% (P<0.02) and 53% (P<0.001), respectively. Transmembrane protein 2 (TMEM2), a protein with homology to fibrocystin, was 2.1-fold higher in individuals with PKD1 mutations (P<0.03). The PC1/TMEM2 ratio correlated inversely with height-adjusted total kidney volume in the discovery cohort, and the ratio of PC1/TMEM2 or PC2/TMEM2 could be used to distinguish individuals with PKD1 mutations from controls in a confirmation cohort. In summary, results of this study suggest that a test measuring the urine exosomal PC1/TMEM2 or PC2/TMEM2 ratio may have utility in diagnosis and monitoring of polycystic kidney disease. Future studies will focus on increasing sample size and confirming these studies. The data were deposited in the ProteomeXchange (identifier PXD001075). PMID:25475747

Out-of-plane three-stable-state ferroelectric switching: Finding the missing middle states

NASA Astrophysics Data System (ADS)

Lee, Jin Hong; Chu, Kanghyun; Kim, Kwang-Eun; Seidel, Jan; Yang, Chan-Ho

2016-03-01

By realizing a nonvolatile third intermediate ferroelectric state through anisotropic misfit strain, we demonstrate electrical switching among three stable out-of-plane polarizations in bismuth ferrite thin films grown on (110) pc-oriented gadolinium scandate substrates (where pc stands for pseudocubic) by the use of an asymmetric external electric field at the step edge of a bottom electrode. We employ phenomenological Landau theory, in conjunction with electrical poling experiments using piezoresponse force microscopy, to understand the role of anisotropic misfit strain and an in-plane electric field in stabilization of multiple ferroelectric states and their competition. Our finding provides a useful insight into multistep ferroelectric switching in rhombohedral ferroelectrics.

Dielectric response of branched copper phthalocyanine

NASA Astrophysics Data System (ADS)

Hamam, Khalil J.; Al-Amar, Mohammad M.; Mezei, Gellert; Guda, Ramakrishna; Burns, Clement A.

2017-09-01

The dielectric constant of pressed pellets and thin films of branched copper phthalocyanine (CuPc) was investigated as a function of frequency from 0.1 kHz to 1 MHz and temperature from 20 °C to 100 °C. Surface morphology was studied using a scanning electron microscope. The high-frequency values of the dielectric constant of pellets and thin films are ~3.5 and ~5.8, respectively. The response was only weakly dependent on frequency and temperature. The branched structure of the CuPc molecules helped to cancel out the effects of low-frequency polarization mechanisms. A planar delocalized charge system with two-dimensional localization was found using time-resolved photoluminescence measurements.

PC index as a proxy of the solar wind energy that entered into the magnetosphere and energy accumulated in the magnetosphere

NASA Astrophysics Data System (ADS)

Troshichev, Oleg; Sormakov, Dmitry

The PC index has been approved by the International Association of Geomagnetism and Aeronomy (Merida, Mexico, 2013) as a new international index of magnetic activity. Application of the PC index as a proxy of a solar wind energy that entered into the magnetosphere determines a principal distinction of the PC index from AL and Dst indices, which are regarded as characteristics of the energy that realized in magnetosphere in form of substorms and magnetic storms. This conclusion is based on results of analysis of relationships between the polar cap magnetic activity (PC-index) and parameters of the solar wind, on the one hand, relationships between changes of PC and development of magnetospheric substorms (AL-index) and magnetic storms (Dst-index), on the other hand. In this study the relationships between the PC and Dst indices in course of more than 200 magnetic storms observed in epoch of solar maximum (1998-2004) have been examined for different classes of storms separated by their kind and intensity. Results of statistical analysis demonstrate that depression of geomagnetic field starts to develop as soon as PC index steadily excess the threshold level ~1.5 mV/m; the storm intensity (DstMIN) follows, with delay ~ 1 hour, the maximum of PC in course of the storm. Main features of magnetic storms are determined, irrespective of their class and intensity, by the accumulated-mean PC value (PCAM): storm is developed as long as PCAM increases, comes to maximal intensity when PCAM attains the maximum, and starts to decay as soon as PCAM value displays decline. The run of “anomalous” magnetic storm on January 21-22, 2005, lasting many hours (with intensity of ≈ -100 nT) under conditions of northward or close to zero BZ component, is perfectly governed by behavior of the accumulated-mean PCAM index and, therefore, this storm should be regarded as an ordinary phenomenon. The conclusion is made that the PC index provides the unique on-line information on solar wind energy that entered into magnetosphere and PCAM index provides information on energy that accumulated in the magnetosphere.

Risk of pancreatic cancer associated with family history of cancer and other medical conditions by accounting for smoking among relatives.

PubMed

Molina-Montes, E; Gomez-Rubio, P; Márquez, M; Rava, M; Löhr, M; Michalski, C W; Molero, X; Farré, A; Perea, J; Greenhalf, W; Ilzarbe, L; O'Rorke, M; Tardón, A; Gress, T; Barberà, V M; Crnogorac-Jurcevic, T; Domínguez-Muñoz, E; Muñoz-Bellvís, L; Balsells, J; Costello, E; Huang, J; Iglesias, M; Kleeff, J; Kong, Bo; Mora, J; Murray, L; O'Driscoll, D; Poves, I; Scarpa, A; Ye, W; Hidalgo, M; Sharp, L; Carrato, A; Real, F X; Malats, N

2018-04-01

Family history (FH) of pancreatic cancer (PC) has been associated with an increased risk of PC, but little is known regarding the role of inherited/environmental factors or that of FH of other comorbidities in PC risk. We aimed to address these issues using multiple methodological approaches. Case-control study including 1431 PC cases and 1090 controls and a reconstructed-cohort study (N = 16 747) made up of their first-degree relatives (FDR). Logistic regression was used to evaluate PC risk associated with FH of cancer, diabetes, allergies, asthma, cystic fibrosis and chronic pancreatitis by relative type and number of affected relatives, by smoking status and other potential effect modifiers, and by tumour stage and location. Familial aggregation of cancer was assessed within the cohort using Cox proportional hazard regression. FH of PC was associated with an increased PC risk [odds ratio (OR) = 2.68; 95% confidence interval (CI): 2.27-4.06] when compared with cancer-free FH, the risk being greater when ≥ 2 FDRs suffered PC (OR = 3.88; 95% CI: 2.96-9.73) and among current smokers (OR = 3.16; 95% CI: 2.56-5.78, interaction FHPC*smoking P-value = 0.04). PC cumulative risk by age 75 was 2.2% among FDRs of cases and 0.7% in those of controls [hazard ratio (HR) = 2.42; 95% CI: 2.16-2.71]. PC risk was significantly associated with FH of cancer (OR = 1.30; 95% CI: 1.13-1.54) and diabetes (OR = 1.24; 95% CI: 1.01-1.52), but not with FH of other diseases. The concordant findings using both approaches strengthen the notion that FH of cancer, PC or diabetes confers a higher PC risk. Smoking notably increases PC risk associated with FH of PC. Further evaluation of these associations should be undertaken to guide PC prevention strategies.

Implementation of RS-485 Communication between PLC and PC of Distributed Control System Based on VB

NASA Astrophysics Data System (ADS)

Lian Zhang, Chuan; Da Huang, Zhi; Qing Zhou, Gui; Chong, Kil To

2015-05-01

This paper focuses on achieving RS-485 communication between programmable logical controller (PLC) and PC based on visual basic 6.0 (VB6.0) on an experimental automatic production line. Mitsubishi FX2N PLCs and a PC are chosen as slave stations and main station, respectively. Monitoring software is developed using VB6.0 for data input/output, flow control and online parameters setting. As a result, all functions are fulfilled with robust performance. It is concluded from results that one PC can monitor several PLCs using RS-485 communication.

Association between prostate cancer and urinary calculi: a population-based study.

PubMed

Chung, Shiu-Dong; Liu, Shih-Ping; Lin, Herng-Ching

2013-01-01

Understanding the reasons underlying the emerging trend and the changing demographics of Asian prostate cancer (PC) has become an important field of study. This study set out to explore the possibility that urinary calculi (UC) and PC may share an association by conducting a case-control study on a population-based database in Taiwan. The cases of this study included 2,900 subjects ≥ 40 years-old who had received their first-time diagnosis of PC and 14,500 randomly selected controls without PC. Conditional logistic regressions were employed to explore the association between PC and having been previously diagnosed with UC. We found that prior UC was found among 608 (21.0%) cases and 2,037 (14.1%) controls (p<0.001). Conditional logistic regression analysis revealed that compared to controls, the odds ratio (OR) of prior UC for cases was 1.63 (95% CI = 1.47-1.80). Furthermore, we found that cases were more likely to have been previously diagnosed with kidney calculus (OR = 1.71; 95% CI = 1.42-2.05), bladder calculus (OR = 2.06; 95% CI = 1.32-3.23), unspecified calculus (OR = 1.66; 95% CI = 1.37-2.00), and ≥2 locations of UC (OR = 1.73; 1.47-2.02) than controls. However, there was no significant relationship between PC and prior ureter calculus. We also found that of the patients with UC, there was no significant difference between PC and treatment method. This investigation detected an association between PC and prior UC. These results highlight a potential target population for PC screening.

Genetic inactivation of prohormone convertase (PC1) causes a reduction in cholecystokinin (CCK) levels in the hippocampus, amygdala, pons and medulla in mouse brain that correlates with the degree of colocalization of PC1 and CCK mRNA in these structures in rat brain.

PubMed

Cain, B M; Connolly, K; Blum, A C; Vishnuvardhan, D; Marchand, J E; Zhu, X; Steiner, D F; Beinfeld, M C

2004-04-01

Prohormone convertase (PC1) is found in endocrine cell lines that express cholecystokinin (CCK) mRNA and process pro CCK to biologically active products. Other studies have demonstrated that PC1 may be a one of the enzymes responsible for the endoproteolytic cleavages that occur in pro CCK during its biosynthesis and processing. Prohormone convertase 1 (PC1) has a distribution that is similar to cholecystokinin (CCK) in rat brain. A moderate to high percentage of CCK mRNA-positive neurons express PC1 mRNA. CCK levels were measured in PC1 knockout and control mice to assess the degree to which loss of PC1 changed CCK content. CCK levels were decreased 62% in hippocampus, 53% in amygdala and 57% in pons-medulla in PC1 knockout mice as compared to controls. These results are highly correlated with the colocalization of CCK and PC1. The majority of CCK mRNA-positive neurons in the pyramidal cell layer of the hippocampus express PC1 mRNA and greater than 50% of CCK mRNA-positive neurons in several nuclei of the amygdala also express PC1. These results demonstrate that PC1 is important for CCK processing. PC2 and PC5 are also widely colocalized with CCK. It may be that PC2, PC5 or another non-PC enzyme are able to substitute for PC1 and sustain production of some amidated CCK. Together these enzymes may represent a redundant system to insure the production of CCK.

The SUrvey for Pulsars and Extragalactic Radio Bursts III: Polarization properties of FRBs 160102 & 151230

NASA Astrophysics Data System (ADS)

Caleb, M.; Keane, E. F.; van Straten, W.; Kramer, M.; Macquart, J. P.; Bailes, M.; Barr, E. D.; Bhat, N. D. R.; Bhandari, S.; Burgay, M.; Farah, W.; Jameson, A.; Jankowski, F.; Johnston, S.; Petroff, E.; Possenti, A.; Stappers, B.; Tiburzi, C.; Krishnan, V. Venkatraman

2018-05-01

We report on the polarization properties of two fast radio bursts (FRBs): 151230 and 160102 discovered in the SUrvey for Pulsars and Extragalactic Radio Bursts (SUPERB) at the Parkes radio telescope. FRB 151230 is observed to be 6 ± 11% circularly polarized and 35 ± 13 % linearly polarized with a rotation measure (RM) consistent with zero. Conversely, FRB 160102 is observed to have a circular polarization fraction of 30 ± 11 %, linear polarization fraction of 84 ± 15 % for RM =-221(6) rad m-2 and the highest measured DM (2596.1 ± 0.3 pc cm-3) for an FRB to date. We examine possible progenitor models for FRB 160102 in extragalactic, non-cosmological and cosmological scenarios. After accounting for the Galactic foreground contribution, we estimate the intrinsic RM to be -256(9) rad m-2 in the low-redshift case and ˜-2.4 × 102 rad m-2 in the high-redshift case. We assess the relative likeliness of these scenarios and how each can be tested. We also place constraints on the scattering measure and study the impact of scattering on the signal's polarization position angle.

In Support of a Distinction between Voluntary and Stimulus-Driven Control: A Review of the Literature on Proportion Congruent Effects.

PubMed

Bugg, Julie M; Crump, Matthew J C

2012-01-01

Cognitive control is by now a large umbrella term referring collectively to multiple processes that plan and coordinate actions to meet task goals. A common feature of paradigms that engage cognitive control is the task requirement to select relevant information despite a habitual tendency (or bias) to select goal-irrelevant information. At least since the 1970s, researchers have employed proportion congruent (PC) manipulations to experimentally establish selection biases and evaluate the mechanisms used to control attention. PC manipulations vary the frequency with which irrelevant information conflicts (i.e., is incongruent) with relevant information. The purpose of this review is to summarize the growing body of literature on PC effects across selective attention paradigms, beginning first with Stroop, and then describing parallel effects in flanker and task-switching paradigms. The review chronologically tracks the expansion of the PC manipulation from its initial implementation at the list-wide level, to more recent implementations at the item-specific and context-specific levels. An important theoretical aim is demonstrating that PC effects at different levels (e.g., list-wide vs. item or context-specific) support a distinction between voluntary forms of cognitive control, which operate based on anticipatory information, and relatively automatic or reflexive forms of cognitive control, which are rapidly triggered by the processing of particular stimuli or stimulus features. A further aim is to highlight those PC manipulations that allow researchers to dissociate stimulus-driven control from other stimulus-driven processes (e.g., S-R responding; episodic retrieval). We conclude by discussing the utility of PC manipulations for exploring the distinction between voluntary control and stimulus-driven control in other relevant paradigms.

In Support of a Distinction between Voluntary and Stimulus-Driven Control: A Review of the Literature on Proportion Congruent Effects

PubMed Central

Bugg, Julie M.; Crump, Matthew J. C.

2012-01-01

Cognitive control is by now a large umbrella term referring collectively to multiple processes that plan and coordinate actions to meet task goals. A common feature of paradigms that engage cognitive control is the task requirement to select relevant information despite a habitual tendency (or bias) to select goal-irrelevant information. At least since the 1970s, researchers have employed proportion congruent (PC) manipulations to experimentally establish selection biases and evaluate the mechanisms used to control attention. PC manipulations vary the frequency with which irrelevant information conflicts (i.e., is incongruent) with relevant information. The purpose of this review is to summarize the growing body of literature on PC effects across selective attention paradigms, beginning first with Stroop, and then describing parallel effects in flanker and task-switching paradigms. The review chronologically tracks the expansion of the PC manipulation from its initial implementation at the list-wide level, to more recent implementations at the item-specific and context-specific levels. An important theoretical aim is demonstrating that PC effects at different levels (e.g., list-wide vs. item or context-specific) support a distinction between voluntary forms of cognitive control, which operate based on anticipatory information, and relatively automatic or reflexive forms of cognitive control, which are rapidly triggered by the processing of particular stimuli or stimulus features. A further aim is to highlight those PC manipulations that allow researchers to dissociate stimulus-driven control from other stimulus-driven processes (e.g., S-R responding; episodic retrieval). We conclude by discussing the utility of PC manipulations for exploring the distinction between voluntary control and stimulus-driven control in other relevant paradigms. PMID:23060836

Can your software engineer program your PLC?

NASA Astrophysics Data System (ADS)

Borrowman, Alastair J.; Taylor, Philip

2016-07-01

The use of Programmable Logic Controllers (PLCs) in the control of large physics experiments is ubiquitous1, 2, 3. The programming of these controllers is normally the domain of engineers with a background in electronics, this paper introduces PLC program development from the software engineer's perspective. PLC programs provide the link between control software running on PC architecture systems and physical hardware controlled and monitored by digital and analog signals. The higher-level software running on the PC is typically responsible for accepting operator input and from this deciding when and how hardware connected to the PLC is controlled. The PLC accepts demands from the PC, considers the current state of its connected hardware and if correct to do so (based upon interlocks or other constraints) adjusts its hardware output signals appropriately for the PC's demands. A published ICD (Interface Control Document) defines the PLC memory locations available to be written and read by the PC to control and monitor the hardware. Historically the method of programming PLCs has been ladder diagrams that closely resemble circuit diagrams, however, PLC manufacturers nowadays also provide, and promote, the use of higher-level programming languages4. Based on techniques used in the development of high-level PC software to control PLCs for multiple telescopes, this paper examines the development of PLC programs to operate the hardware of a medical cyclotron beamline controlled from a PC using the Experimental Physics and Industrial Control System (EPICS), which is also widely used in telescope control5, 6, 7. The PLC used is the new generation Siemens S7-1200 programmed using Siemens Pascal based Structured Control Language (SCL), which is their implementation of Structured Text (ST). The approach described is that from a software engineer's perspective, utilising Siemens Totally Integrated Automation (TIA) Portal integrated development environment (IDE) to create modular PLC programs based upon reusable functions capable of being unit tested without the PLC connected to hardware. Emphasis has been placed on designing an interface between EPICS and SCL that enforces correct operation of hardware through stringent separation of PC accessible PLC memory and hardware I/O addresses used only by the PLC. The paper also introduces the method used to automate the creation, from the same source document, the PLC memory structure (tag) definitions (defining memory used to access hardware I/O and that accessed by the PC) and creation of the PC program data structures (EPICS database records) used to access the permitted PLC addresses. From direct experience this paper demonstrates the advantages of PLC program development being shared between electronic and software engineers, to enable use of the most appropriate processes from both the perspective of the hardware and the higher-level software used to control it.

Extracellular matrix specific protein fingerprints measured in serum can separate pancreatic cancer patients from healthy controls

PubMed Central

2013-01-01

Background Pancreatic cancer (PC) is an aggressive disease with an urgent need for biomarkers. Hallmarks of PC include increased collagen deposition (desmoplasia) and increased matrix metalloproteinase (MMP) activity. The aim of this study was to investigate whether protein fingerprints of specific MMP-generated collagen fragments differentiate PC patients from healthy controls when measured in serum. Methods The levels of biomarkers reflecting MMP-mediated degradation of type I (C1M), type III (C3M) and type IV (C4M, C4M12a1) collagen were assessed in serum samples from PC patients (n = 15) and healthy controls (n = 33) using well-characterized and validated competitive ELISAs. Results The MMP-generated collagen fragments were significantly elevated in serum from PC patients as compared to controls. The diagnostic power of C1M, C3M, C4M and C4M12 were ≥83% (p < 0.001) and when combining all biomarkers 99% (p < 0.0001). Conclusions A panel of serum biomarkers reflecting altered MMP-mediated collagen turnover is able to differentiate PC patients from healthy controls. These markers may increase the understanding of mode of action of the disease and, if validated in larger clinical studies, provide an improved and additional tool in the PC setting. PMID:24261855

East Greenland and Barents Sea polar bears (Ursus maritimus): adaptive variation between two populations using skull morphometrics as an indicator of environmental and genetic differences.

PubMed

Pertoldi, Cino; Sonne, Christian; Wiig, Øystein; Baagøe, Hans J; Loeschcke, Volker; Bechshøft, Thea Østergaard

2012-06-01

A morphometric study was conducted on four skull traits of 37 male and 18 female adult East Greenland polar bears (Ursus maritimus) collected 1892-1968, and on 54 male and 44 female adult Barents Sea polar bears collected 1950-1969. The aim was to compare differences in size and shape of the bear skulls using a multivariate approach, characterizing the variation between the two populations using morphometric traits as an indicator of environmental and genetic differences. Mixture analysis testing for geographic differentiation within each population revealed three clusters for Barents Sea males and three clusters for Barents Sea females. East Greenland consisted of one female and one male cluster. A principal component analysis (PCA) conducted on the clusters defined by the mixture analysis, showed that East Greenland and Barents Sea polar bear populations overlapped to a large degree, especially with regards to females. Multivariate analyses of variance (MANOVA) showed no significant differences in morphometric means between the two populations, but differences were detected between clusters from each respective geographic locality. To estimate the importance of genetics and environment in the morphometric differences between the bears, a PCA was performed on the covariance matrix derived from the skull measurements. Skull trait size (PC1) explained approx. 80% of the morphometric variation, whereas shape (PC2) defined approx. 15%, indicating some genetic differentiation. Hence, both environmental and genetic factors seem to have contributed to the observed skull differences between the two populations. Overall, results indicate that many Barents Sea polar bears are morphometrically similar to the East Greenland ones, suggesting an exchange of individuals between the two populations. Furthermore, a subpopulation structure in the Barents Sea population was also indicated from the present analyses, which should be considered with regards to future management decisions. © 2012 The Authors.

Investigating the composition characteristics of dissolved and particulate/colloidal organic matter in effluent-dominated stream using fluorescence spectroscopy combined with multivariable analysis.

PubMed

Yu, Min-Da; He, Xiao-Song; Xi, Bei-Dou; Gao, Ru-Tai; Zhao, Xian-Wei; Zhang, Hui; Huang, Cai-Hong; Tan, Wenbing

2018-03-01

Fluorescence excitation-emission matrix (EEM) spectroscopy combined with principal component analysis (PCA) and parallel factor analysis (PARAFAC) were used to investigate the compositional characteristics of dissolved and particulate/colloidal organic matter and its correlations with nitrogen, phosphorus, and heavy metals in an effluent-dominated stream, Northern China. The results showed that dissolved organic matter (DOM) was comprised of fulvic-like, humic-like, and protein-like components in the water samples, and fulvic-like substances were the main fraction of DOM among them. Particulate/colloidal organic matter (PcOM) consisted of fulvic-like and protein-like matter. Fulvic-like substances existed in the larger molecular form in PcOM, and they comprised a large amount of nitrogen and polar functional groups. On the other hand, protein-like components in PcOM were low in benzene ring and bound to heavy metals. It could be concluded that nitrogen, phosphorus, and heavy metals in effluent had an effect on the compositional characteristics of natural DOM and PcOM, which may deepen our understanding about the environmental behaviors of organic matter in effluent.

Cholesterol blocks spontaneous insertion of membrane proteins into liposomes of phosphatidylcholine.

PubMed

Nakamura, Shota; Suzuki, Sonomi; Saito, Hiroaki; Nishiyama, Ken-Ichi

2018-04-01

Spontaneous insertion of membrane proteins into liposomes formed from Escherichia coli polar phospholipids is blocked by diacylglycerol (DAG) at a physiological level. We found that cholesterol also blocks this spontaneous insertion, although a much larger amount is necessary for sufficient blockage. Reversely, sphingomyelin enhanced the spontaneous insertion. DAG at a physiological level was found not to block spontaneous insertion into liposomes formed from phosphatidylcholine (PC), while non-physiologically high concentrations of DAG reduced it. On the other hand, cholesterol blocked the spontaneous insertion into PC liposomes at a physiological level, explaining that both PC and cholesterol are absent in E. coli. While sphingomyelin did not enhance spontaneous insertion into PC liposomes, the effect of cholesterol on blockage of spontaneous insertion was dominant over that of sphingomyelin, suggesting that cholesterol functions as a blocker of disordered spontaneous insertion in eukaryotic cells. Lower amount of cholesterol was necessary to block spontaneous insertion into ER-mimic liposomes, explaining that ER membranes contain less amount of cholesterol. These results also explain that cholesterol, but not DAG, is involved in blockage of spontaneous insertion in eukaryotic cells, since DAG plays an important role as a second messenger in signal transduction.

The role of inhibition by phosphocitrate and its analogue in chondrocyte differentiation and subchondral bone advance in Hartley guinea pigs

PubMed Central

Sun, Yubo; Kiraly, Alex J.; Cox, Michael; Mauerhan, David R.; Hanley, Edward N.

2018-01-01

Phosphocitrate (PC) and its analogue, PC-β ethyl ester, inhibit articular cartilage degeneration in Hartley guinea pigs. However, the underlying molecular mechanisms remain unclear. The present study aimed to investigate the hypothesis that PC exerted its disease-modifying effect on osteoarthritis (OA), in part, by inhibiting a molecular program similar to that in the endochondral pathway of ossification. The results demonstrated that severe proteoglycan loss occurred in the superficial and middle zones, as well as in the calcified zone of articular cartilage in the Hartley guinea pigs. Subchondral bone advance was greater in the control Hartley guinea pigs compared with PC- or PC analogue-treated guinea pigs. Resorption of cartilage bars or islands and vascular invasion in the growth plate were also greater in the control guinea pigs compared with the PC- or PC analogue-treated guinea pigs. The levels of matrix metalloproteinase-13 and type X collagen within the articular cartilage and growth plate were significantly increased in the control guinea pigs compared with PC-treated guinea pigs (P<0.05). These results indicated that articular chondrocytes in Hartley guinea pigs exhibited a hypertrophic phenotype and recapitulated a developmental molecular program similar to the endochondral pathway of ossification. Activation of this molecular program resulted in resorption of calcified articular cartilage and subchondral bone advance. This suggests that PC and PC analogues exerted their OA disease-modifying activity, in part, by inhibiting this molecular program. PMID:29545850

The origin of the mid-infrared nuclear polarization of active galactic nuclei

NASA Astrophysics Data System (ADS)

Lopez-Rodriguez, E.; Alonso-Herrero, A.; Diaz-Santos, T.; Gonzalez-Martin, O.; Ichikawa, K.; Levenson, N. A.; Martinez-Paredes, M.; Nikutta, R.; Packham, C.; Perlman, E.; Almeida, C. Ramos; Rodriguez-Espinosa, J. M.; Telesco, C. M.

2018-05-01

We combine new (NGC 1275, NGC 4151, and NGC 5506) and previously published (Cygnus A, Mrk 231, and NGC 1068) sub-arcsecond resolution mid-infrared (MIR; 8-13 μm) imaging- and spectro-polarimetric observations of six Seyfert galaxies using CanariCam on the 10.4-m Gran Telescopio CANARIAS. These observations reveal a diverse set of physical processes responsible for the nuclear polarization, and permit characterization of the origin of the MIR nuclear polarimetric signature of active galactic nuclei (AGN). For all radio quiet objects, we found that the nuclear polarization is low (<1 per cent), and the degree of polarization is often a few per cent over extended regions of the host galaxy where we have sensitivity to detect such extended emission (i.e., NGC 1068 and NGC 4151). We suggest that the higher degree of polarization previously found in lower resolution data arises only on the larger-than-nuclear scales. Only the radio-loud Cygnus A exhibits significant nuclear polarization (˜11 per cent), attributable to synchrotron emission from the pc-scale jet close to the core. We present polarization models that suggest that the MIR nuclear polarization for highly obscured objects arises from a self-absorbed MIR polarized clumpy torus and/or dichroism from the host galaxy, while for unabsorbed cores, MIR polarization arises from dust scattering in the torus and/or surrounding nuclear dust.

Evidence for Intermediate Polars as the Origin of the Galactic Center Hard X-Ray Emission

NASA Technical Reports Server (NTRS)

Hailey, Charles J.; Mori, Kaya; Perez, Kerstin; Canipe, Alicia M.; Hong, Jaesub; Tomsick, John A.; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Fornasini, Francesa;

Perceived control and intrinsic vs. extrinsic motivation for oral self-care: a full factorial experimental test of theory-based persuasive messages.

PubMed

Staunton, Liam; Gellert, Paul; Knittle, Keegan; Sniehotta, Falko F

2015-04-01

Correlational evidence suggests that perceived control (PC) and intrinsic motivation (IM), key constructs in social cognitive and self-determination theories, may interact to reinforce behavior change. This proof-of-principle study examines the independent and synergistic effects of interventions to increase PC and IM upon dental flossing frequency. University students (n = 185) were randomized in a 2 × 2 full factorial design to receive two computer-based interventions: one to either increase or decrease PC and another to increase either IM or extrinsic motivation. These constructs were measured immediately post-intervention; flossing behavior was measured 1 week later. The interventions to increase PC and PC/IM had main and interaction effects on flossing, respectively. The PC/IM interaction effect was mediated by increases in PC and IM. Combining interventions to increase PC and IM seems to be a promising avenue of research, which has implications for both theory and intervention development.

Functional recovery in rat spinal cord injury induced by hyperbaric oxygen preconditioning.

PubMed

Lu, Pei-Gang; Hu, Sheng-Li; Hu, Rong; Wu, Nan; Chen, Zhi; Meng, Hui; Lin, Jiang-Kai; Feng, Hua

2012-12-01

It is a common belief that neurosurgical interventions can cause inevitable damage resulting from the procedure itself in surgery especially for intramedullary spinal cord tumors. The present study was designed to examine if hyperbaric oxygen preconditioning (HBO-PC) was neuroprotective against surgical injuries using a rat model of spinal cord injury (SCI). Sprague-Dawley rats were randomly divided into three groups: HBO-PC group, hypobaric hypoxic preconditioning (HH-PC) control group, and normobaric control group. All groups were subjected to SCI by weight drop device. Rats from each group were examined for neurological behavior and electrophysiological function. Tissue sections were analyzed by using immunohistochemistry, TdT-mediated dUTP-biotin nick end labeling, and axonal tract tracing. Significant neurological deficits were observed after SCI and HBO-PC and HH-PC improved neurological deficits 1 week post-injury. The latencies of motor-evoked potential and somatosensory-evoked potential were significantly delayed after SCI, which was attenuated by HBO-PC and HH-PC. Compared with normobaric control group, pretreatment with HBO and hypobaric hypoxia significantly reduced the number of TdT-mediated dUTP-biotin nick end labeling-positive cells, and increased nestin-positive cells. HBO-PC and HH-PC enhanced axonal growth after SCI. In conclusion, preconditioning with HBO and hypobaric hypoxia can facilitate functional recovery and suppress cell apoptosis after SCI and may prove to be a useful preventive strategy to neurosurgical SCI.

Tuning exchange interactions in organometallic semiconductors

NASA Astrophysics Data System (ADS)

Rawat, Naveen; Manning, Lane W.; Hua, Kim-Ngan; Headrick, Randall L.; Cherian, Judy G.; Bishop, Michael M.; McGill, Stephen A.; Furis, Madalina I.

2015-09-01

Organic semiconductors are emerging as a leading area of research as they are expected to overcome limitations of inorganic semiconductor devices for certain applications where low cost manufacturing, device transparency in the visible range or mechanical flexibility are more important than fast switching times. Solution processing methods produce thin films with millimeter sized crystalline grains at very low cost manufacturing prices, ideally suited for optical spectroscopy investigations of long range many-body effects in organic systems. To this end, we synthesized an entire family of organosoluble 3-d transition metal Pc's and successfully employed a novel solution-based pen-writing deposition technique to fabricate long range ordered thin films of mixtures of metal-free (H2Pc) molecule and organometallic phthalocyanines (MPc's). Our previous studies on the parent MPc crystalline thin films identified different electronic states mediating exchange interactions in these materials. This understanding of spin-dependent exchange interaction between delocalized π-electrons with unpaired d spins enabled the further tuning of these interactions by mixing CoPc and H2Pc in different ratios ranging from 1:1 to 1000:1 H2Pc:MPc. The magnitude of the exchange is also tunable as a function of the average distance between unpaired spins in these materials. Furthermore, high magnetic field (B < 25T) MCD and magneto-photoluminescence show evidence of spin-polarized band-edge excitons in the same materials.

The effects of IL-1β, IL-8, G-CSF and TNF-α as molecular adjuvant on the immune response to an E. tarda subunit vaccine in flounder (Paralichthys olivaceus).

PubMed

Guo, Ming; Tang, Xiaoqian; Sheng, Xiuzhen; Xing, Jing; Zhan, Wenbin

2018-06-01

Cytokines play vital roles in mounting immune responses and activating host defense network. In this study, the expression plasmid pcDNA3.1 (pcN3) encoding four flounder (Paralichthys olivaceus) cytokines including IL-1β, TNF-α, IL-8 or G-CSF (pcIL-1β, pcTNF-α, pcIL-8 and pcG-CSF) were successfully constructed, and their adjuvant potential on an Edwardsiella tarda (E. tarda) subunit vaccine OmpV (rOmpV) were comparatively analyzed in vaccinated flounder model. Results revealed that flounder vaccinated with rOmpV plus pcIL-1β, pcIL-8 or pcG-CSF produced the relative percent survivals (RPS) of 71%, 65% and 49% respectively, which were higher than that in flounder vaccinated with rOmpV plus pcTNF-α (39%) or pcN3 (36%, the control group). Immunological analysis showed that: (1) except pcTNF-α, higher levels of anti-E. tarda serum antibodies and sIg + lymphocytes in spleen, head kidney and peripheral blood were significantly enhanced by pcIL-1β, pcIL-8 or pcG-CSF, however, pcIL-8 and pcIL-1β enhanced higher levels of sIg + lymphocytes and anti-E. tarda antibodies than pcG-CSF; (2) pcTNF-α could promote the up-regulation of genes participated in cellular immunity (MHCIα, IFN-γ, CD8α and CD8β), pcIL-1β could enhance the expression of genes related to humoral immunity (CD4-1, CD4-2, MHCIIα and IgM), and all the detected genes were augmented by pcIL-8 and pcG-CSF; Among the four cytokines, pcIL-8 and pcIL-1β could strengthen the highest levels of genes participated in cellular immunity and humoral immunity, respectively. These results demonstrated that pcIL-8 and pcIL-1β could enhance stronger cellular and/or humoral immunity induced by rOmpV than pcG-CSF and pcTNF-α, and evoked higher RPS against E. tarda challenge in flounder, which indicated that pcIL-8 and pcIL-1β are promising adjuvants of vaccines in controlling E. tarda infection. Copyright © 2018 Elsevier Ltd. All rights reserved.

PCN-index derivation at World Data Center for Geomagnetism, Copenhagen, DTU Space

NASA Astrophysics Data System (ADS)

Stolle, C.; Matzka, J.

2012-04-01

The Polar Cap North (PCN) index is based on a correlation between geomagnetic disturbances at the Qaanaaq geomagnetic observatory (IAGA code THL) and the merging electric field derived from solar wind parameters. The index is therefore meant to provide a fast ground based single station indicator for variations in the merging electric field without being dependent on satellite observations. The PC index will be subject to an IAGA endorsement process during IAGA Scientific Assembly 2013. Actually the WDC provides near real time PC-indices and post-processed final PC-indices based on former developed algorithms. However, the coefficients used for calculating the PCN distributed by the WDC Copenhagen are presently not reproducible. In the frame of the IAGA endorsement, DTU Space tests new coefficients mainly based on published algorithms. This presentation will report on activities at the WDC Copenhagen and on the current status at DTU Space with respect to the preparation for the IAGA endorsement process of the PCN-index.

Penetration electric fields: A Volland Stern approach

NASA Astrophysics Data System (ADS)

Burke, William J.

2007-07-01

This paper reformulates the Volland Stern model, separating contributions from corotation and convection to predict electric field penetration of the inner magnetosphere using data from the Advanced Composition Explorer (ACE) satellite. In the absence of shielding, the model electric field is EVS=ΦPC/2LYRE, where ΦPC is the polar cap potential and 2LYRE is the width of the magnetosphere along the dawn dusk meridian. ΦPC is estimated from the interplanetary electric field (IEF) and the dynamic pressure of the solar wind (PSW); values of LY were approximated using PSW and simple force-balance considerations. ACE measurements on 16 17 April 2002 were then used to calculate EVS for comparison with the eastward electric field component (EJφ) detected by the incoherent scatter radar at Jicamarca, Peru. While the interplanetary magnetic field (IMF) was southward, the model predicted observed ratios of EVS/IEF. During intervals of northward IMF, EJφ turned westward suggesting that a northward IMF BZ system of field-aligned currents affected the electrodynamics of the dayside ionosphere on rapid time scales.

Interconnected nitrogen and sulfur dual-doped porous carbon as efficient electrocatalyst for triiodide reduction in dye-sensitized solar cells

NASA Astrophysics Data System (ADS)

Li, Zhao; Yang, Wang; Xu, Xiuwen; Tang, Yushu; Zeng, Ziwei; Yang, Fan; Zhang, Liqiang; Ning, Guoqing; Xu, Chunming; Li, Yongfeng

2016-09-01

Exploiting cost-effective and efficient counter electrodes (CEs) for the reduction of triiodide (I3-) has been a persistent objective for the development of dye-sensitized solar cells (DSSCs). Here, we propose a strategy for the synthesis of nitrogen and sulfur dual-doped porous carbon (N/S-PC) via a thermal annealing approach by using melamine as N source, and basic magnesium sulfate (BMS) whiskers as S source and templates. Benefiting from the high surface area, unique interconnected structural feature and synergistic effects of N/S dual-doping, the N/S-PC shows excellent electrocatalytic activity toward I3- reduction, which has simultaneously been confirmed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Tafel polarization measurements. The DSSC devices with N/S-PC CEs exhibit a PCE up to 7.41%, which is higher than that of DSSC devices with single heteroatom (N or S) doped CEs and even Pt CEs (7.14%).

NEAR-INFRARED CIRCULAR AND LINEAR POLARIMETRY OF MONOCEROS R2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwon, Jungmi; Tamura, Motohide; Hough, James H.

We have conducted simultaneous JHK{sub s}-band imaging circular and linear polarimetry of the Monoceros R2 (Mon R2) cluster. We present results from deep and wide near-infrared linear polarimetry of the Mon R2 region. Prominent and extended polarized nebulosities over the Mon R2 field are revisited, and an infrared reflection nebula associated with the Mon R2 cluster and two local reflection nebulae, vdB 67 and vdB 69, is detected. We also present results from deep imaging circular polarimetry in the same region. For the first time, the observations show relatively high degrees of circular polarization (CP) in Mon R2, with asmore » much as approximately 10% in the K{sub s} band. The maximum CP extent of a ring-like nebula around the Mon R2 cluster is approximately 0.60 pc, while that of a western nebula, around vdB 67, is approximately 0.24 pc. The extended size of the CP is larger than those seen in the Orion region around IRc2, while the maximum degree of CP of ∼10% is smaller than those of ∼17% seen in the Orion region. Nonetheless, both the CP size and degree of this region are among the largest in our infrared CP survey of star-forming regions. We have also investigated the time variability of the degree of the polarization of several infrared sources and found possible variations in three sources.« less

Intelligent control system based on ARM for lithography tool

NASA Astrophysics Data System (ADS)

Chen, Changlong; Tang, Xiaoping; Hu, Song; Wang, Nan

2014-08-01

The control system of traditional lithography tool is based on PC and MCU. The PC handles the complex algorithm, human-computer interaction, and communicates with MCU via serial port; The MCU controls motors and electromagnetic valves, etc. This mode has shortcomings like big volume, high power consumption, and wasting of PC resource. In this paper, an embedded intelligent control system of lithography tool, based on ARM, is provided. The control system used S5PV210 as processor, completing the functions of PC in traditional lithography tool, and provided a good human-computer interaction by using LCD and capacitive touch screen. Using Android4.0.3 as operating system, the equipment provided a cool and easy UI which made the control more user-friendly, and implemented remote control and debug, pushing video information of product by network programming. As a result, it's convenient for equipment vendor to provide technical support for users. Finally, compared with traditional lithography tool, this design reduced the PC part, making the hardware resources efficiently used and reducing the cost and volume. Introducing embedded OS and the concepts in "The Internet of things" into the design of lithography tool can be a development trend.

Design and fabrication of an angle-scanning based platform for the construction of surface plasmon resonance biosensor

NASA Astrophysics Data System (ADS)

Hu, Jiandong; Cao, Baiqiong; Wang, Shun; Li, Jianwei; Wei, Wensong; Zhao, Yuanyuan; Hu, Xinran; Zhu, Juanhua; Jiang, Min; Sun, Xiaohui; Chen, Ruipeng; Ma, Liuzheng

2016-03-01

A sensing system for an angle-scanning optical surface-plasmon-resonance (SPR) based biosensor has been designed with a laser line generator in which a P polarizer is embedded to utilize as an excitation source for producing the surface plasmon wave. In this system, the emitting beam from the laser line generator is controlled to realize the angle-scanning using a variable speed direct current (DC) motor. The light beam reflected from the prism deposited with a 50 nm Au film is then captured using the area CCD array which was controlled by a personal computer (PC) via a universal serial bus (USB) interface. The photoelectric signals from the high speed digital camera (an area CCD array) were converted by a 16 bit A/D converter before it transferred to the PC. One of the advantages of this SPR biosensing platform is greatly demonstrated by the label-free and real-time bio-molecular analysis without moving the area CCD array by following the laser line generator. It also could provide a low-cost surface plasmon resonance platform to improve the detection range in the measurement of bioanalytes. The SPR curve displayed on the PC screen promptly is formed by the effective data from the image on the area CCD array and the sensing responses of the platform to bulk refractive indices were calibrated using various concentrations of ethanol solution. These ethanol concentrations indicated with volumetric fraction of 5%, 10%, 15%, 20%, and 25%, respectively, were experimented to validate the performance of the angle-scanning optic SPR biosensing platform. As a result, the SPR sensor was capable to detect a change in the refractive index of the ethanol solution with the relative high linearity at the correlation coefficient of 0.9842. This greatly enhanced detection range is obtained from the position relationship between the laser line generator and the right-angle prism to allow direct quantification of the samples over a wide range of concentrations.

Relativistic Acceleration of Electrons Injected by a Plasma Mirror into a Radially Polarized Laser Beam.

PubMed

Zaïm, N; Thévenet, M; Lifschitz, A; Faure, J

2017-09-01

We propose a method to generate femtosecond, relativistic, and high-charge electron bunches using few-cycle and tightly focused radially polarized laser pulses. In this scheme, the incident laser pulse reflects off an overdense plasma that injects electrons into the reflected pulse. Particle-in-cell simulations show that the plasma injects electrons ideally, resulting in a dramatic increase of charge and energy of the accelerated electron bunch in comparison to previous methods. This method can be used to generate femtosecond pC bunches with energies in the 1-10 MeV range using realistic laser parameters corresponding to current kHz laser systems.

Structural phase transitions in SrTiO 3 nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Han; Liu, Sizhan; Scofield, Megan E.

2017-07-31

Pressure dependent structural measurements on monodispersed nanoscale SrTiO3 samples with average diameters of 10 to ~80 nm were conducted to enhance the understanding of the structural phase diagram of nanoscale SrTiO3. A robust pressure independent polar structure was found in the 10 nm sample for pressures up to 13 GPa, while a size dependent cubic to tetragonal transition occurs (at P = Pc) for larger particle sizes. The results suggest that the growth of ~10 nm STO particles on substrates with significant lattice mismatch may maintain a polar state for a large range of strain values, possibly enabling device use.

Retina-like sensor image coordinates transformation and display

NASA Astrophysics Data System (ADS)

Cao, Fengmei; Cao, Nan; Bai, Tingzhu; Song, Shengyu

2015-03-01

For a new kind of retina-like senor camera, the image acquisition, coordinates transformation and interpolation need to be realized. Both of the coordinates transformation and interpolation are computed in polar coordinate due to the sensor's particular pixels distribution. The image interpolation is based on sub-pixel interpolation and its relative weights are got in polar coordinates. The hardware platform is composed of retina-like senor camera, image grabber and PC. Combined the MIL and OpenCV library, the software program is composed in VC++ on VS 2010. Experience results show that the system can realizes the real-time image acquisition, coordinate transformation and interpolation.

KSC-98pc1211

NASA Image and Video Library

1998-10-02

KENNEDY SPACE CENTER, FLA. --Out of its crate, the Mars Polar Lander is maneuvered inside the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2) for testing. The Mars Polar Lander is targeted for launch from Cape Canaveral Air Station aboard a Delta II rocket on Jan. 3, 1999. The solar-powered spacecraft is designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere

Synthesis and characterization of monoisomeric 1,8,15,22-substituted (A3B and A2B2) phthalocyanines and phthalocyanine-fullerene dyads.

PubMed

Ranta, Jenni; Kumpulainen, Tatu; Lemmetyinen, Helge; Efimov, Alexander

2010-08-06

Synthesis and characterization of three phthalocyanine-fullerene (Pc-C(60)) dyads, corresponding monoisomeric phthalocyanines (Pc), and building blocks, phthalonitriles, are described. Six novel bisaryl phthalonitriles were prepared by the Suzuki-Miyaura coupling reaction from trifluoromethanesulfonic acid 2,3-dicyanophenyl ester and various oxaborolanes. Two phthalonitriles were selected for the synthesis of A(3)B- and A(2)B(2)-type phthalocyanines. Phthalonitrile 4 has a bulky 3,5-di-tert-butylphenyl substituent at the alpha-phthalo position, which forces only one regioisomer to form and greatly increases the solubility of phthalocyanine. Phthalonitrile 8 has a 3-phenylpropanol side chain at the alpha-position making further modifications of the side group possible. Synthesized monoisomeric A(3)B- and A(2)B(2)-type phthalocyanines are modified by attachment of malonic residues. Finally, fullerene is covalently linked to phthalocyanine with one or two malonic bridges to produce Pc-C(60) dyads. Due to the monoisomeric structure and increased solubility of phthalocyanines, the quality of NMR spectra of the compounds is enhanced significantly, making detailed NMR analysis of the structures possible. The synthesized dyads have different orientations of phthalocyanine and fullerene, which strongly influence the electron transfer (ET) from phthalocyanine to fullerene moiety. Fluorescence quenchings of the dyads were measured in both polar and nonpolar solvents, and in all cases, the quenching was more efficient in the polar environment. As expected, most efficient fluorescence quenching was observed for dyad 20b, with two linkers and phthalocyanine and fullerene in face-to-face orientation.

Population-based study of the association of variants in mismatch repair genes with prostate cancer risk and outcomes

PubMed Central

Langeberg, Wendy J.; Kwon, Erika M.; Koopmeiners, Joseph S.; Ostrander, Elaine A.; Stanford, Janet L.

2009-01-01

Background Mismatch repair (MMR) gene activity may be associated with prostate cancer (PC) risk and outcomes. This study evaluated whether single nucleotide polymorphisms (SNPs) in key MMR genes are related to PC outcomes. Methods Data from two population-based case-control studies of PC among Caucasian and African-American men residing in King County, Washington were combined for this analysis. Cases (n=1,458) were diagnosed with PC in 1993–96 or 2002–05 and identified via the Seattle-Puget Sound SEER cancer registry. Controls (n=1,351) were age-matched to cases and identified via random digit dialing. Logistic regression was used to assess the relationship between haplotype-tagging SNPs and PC risk and disease aggressiveness. Cox proportional hazards regression was used to assess the relationship between SNPs and PC recurrence and PC-specific death. Results Nineteen SNPs were evaluated in the key MMR genes: five in MLH1, 10 in MSH2, and 4 in PMS2. Among Caucasian men, one SNP in MLH1 (rs9852810) was associated with: overall PC risk (OR=1.21, 95% CI=1.02, 1.44; p=0.03), more aggressive PC (OR=1.49, 95% CI=1.15–1.91; p<0.01), and PC recurrence (HR=1.83, 95% CI=1.18, 2.86; p<0.01), but not PC-specific mortality. A non-synonymous coding SNP in MLH1, rs1799977 (I219V), was also found to be associated with more aggressive disease. These results did not remain significant after adjusting for multiple comparisons. Conclusion This population-based case-control study provides evidence for a possible association with a gene variant in MLH1 in relation to risk of overall PC, more aggressive disease, and PC recurrence, which warrants replication. PMID:20056646

76 FR 56821 - Submission for OMB Review; Request for Comments

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-14

... collection OMB Control No. 0420-0510: Health History (PC-1789) and Report of Medical Examination (PC-1790 and...: Denora Miller at Peace Corps address above. SUPPLEMENTARY INFORMATION: Title: Health History (PC-1789... reply: Voluntary. Burden to the public: The revised Health History (PC-1789) is expected to average 30...

Observations of a Unique Type of ULF Wave by Low-Altitude Space Technology 5 Satellites

NASA Technical Reports Server (NTRS)

Le, G.; Chi, P. J.; Strangeway, R. J.; Slavin, J. A.

2011-01-01

We report a unique type of ULF waves observed by low-altitude Space Technology 5 (ST-5) constellation mission. ST-5 is a three-microsatellite constellation deployed into a 300 x 4500 km dawn-dusk and Sun-synchronous polar orbit with 105.6deg inclination angle. Because of the Earth's rotation and the dipole tilt effect, the spacecraft's dawn-dusk orbit track can reach as low as subauroral latitudes during the course of a day. Whenever the spacecraft traverse the dayside closed field line region at subauroral latitudes, they frequently observe strong transverse oscillations at 30-200 mHz, or in the Pc2-3 frequency range. These Pc2-3 waves appear as wave packets with durations in the order of 5-10 min. As the maximum separations of the ST-5 spacecraft are in the order of 10 min, the three ST-5 satellites often observe very similar wave packets, implying these wave oscillations occur in a localized region. The coordinated ground-based magnetic observations at the spacecraft footprints, however, do not see waves in the Pc2-3 band; instead, the waves appear to be the common Pc4-5 waves associated with field line resonances. We suggest that these unique Pc2-3 waves seen by ST-5 are in fact the Doppler-shifted Pc4-5 waves as a result of rapid traverse of the spacecraft across the resonant field lines azimuthally at low altitudes. The observations with the unique spacecraft dawn-dusk orbits at proper altitudes and magnetic latitudes reveal the azimuthal characteristics of field line resonances.

Graphene-enhanced intermolecular interaction at interface between copper- and cobalt-phthalocyanines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dou, Wei-Dong; Center of Super-Diamond and Advanced Films; Huang, Shu-Ping

2015-10-07

Interfacial electronic structures of copper-phthalocyanine (CuPc), cobalt-phthalocyanine (CoPc), and graphene were investigated experimentally by using photoelectron spectroscopy. While the CuPc/graphene interface shows flat band structure and negligible interfacial dipole indicating quite weak molecule-substrate interaction, the CuPc/CoPc/graphene interface shows a large interfacial dipole and obvious energy level bending. Controlled experiments ruled out possible influences from the change in film structure of CuPc and pure π–π interaction between CoPc and CuPc. Analysis based on X-ray photoelectron spectroscopy and density functional theory reveals that the decrease in the work function for the CuPc/CoPc/graphene system is induced by the intermolecular interaction between CuPc andmore » CoPc which is enhanced owning to the peculiar electronic properties at the CoPc-graphene interface.« less

Nonlinear dielectric spectroscopy of propylene carbonate derivatives

NASA Astrophysics Data System (ADS)

Casalini, R.; Roland, C. M.

2018-04-01

Nonlinear dielectric measurements were carried out on two strongly polar liquids, 4-vinyl-1,3-dioxolan-2-one (VPC) and 4-ethyl-1,3-dioxolan-2-one (EPC), having chemical structures differing from propylene carbonate (PC) only by the presence of a pendant group. Despite their polarity, the compounds are all non-associated, "simple" liquids. From the linear component of the dielectric response, the α relaxation peak breadth was found to be invariant at a fixed value of the relaxation time, τα. From spectra from the nonlinear component, the number of dynamically correlated molecules was determined; it was also constant at fixed τα. Thus, two manifestations of dynamic heterogeneity depend only on the time constant for structural reorientation. More broadly, the cooperativity of molecular motions for non-associated glass-forming materials is connected to (i.e., reciprocally governs) the time scale. The equation of state for the two liquids was also obtained from density measurements made over a broad range of pressures and temperatures. Using these data, it was determined that the relaxation times of both liquids conform to density scaling. The effect of density, relative to thermal effects, on the α relaxation increases going from PC < VPC < EPC.

Stereoscopic Movies for Teaching and Learning of Astronomy

NASA Astrophysics Data System (ADS)

Hayashi, Mitsuru; Kato, Tsunehiko N.; Takeda, Takaaaki; Kokubo, Eiichiro; Miura, Hitoshi; Takahei, Toshiyuki; Miyama, Shoken M.; Kaifu, Norio

To attract the interest of the public in astronomy we visualize data obtained through simulations by using super computers and observations by using state-of -the-art facilities for example the SUBARU Telescope in the virtual reality system. The system is composed of three soft screens. We use two PC's two DLP projectors with circular polarization filters and one mirror for each screen to realize stereoscopic projection. By wearing glasses of circular polarization filters we can experience immersiveness in the system. Six PC's are connected by using optical fiber cable(1Gbps). Especially we developed the software for synchronization and realized stereoscopic movies(15-30 frames per second). In addition to teaching and learning of astronomy we also utilize the system above for public relations and science itself in NAO Mitaka. The system can provide scientists with the point of view we cannot realize on the earth. We are planning to improve the contents easier for the public to understand and distribute the contents to museums and educational institutions through networks for example Super SINET(the internet backbone connects institutes at 10Gbps) in 2003 in addition to monthly exhibition in NAOMitaka

Raman Spectroscopy of 3-D Printed Polymers

NASA Astrophysics Data System (ADS)

Espinoza, Vanessa; Wood, Erin; Hight Walker, Angela; Seppala, Jonathan; Kotula, Anthony

Additive manufacturing (AM) techniques, such as 3-D printing are becoming an innovative and efficient way to produce highly customized parts for applications ranging from automotive to biomedical. Polymer-based AM parts can be produced from a myriad of materials and processing conditions to enable application-specific products. However, bringing 3-D printing from prototype to production relies on understanding the effect of processing conditions on the final product. Raman spectroscopy is a powerful and non-destructive characterization technique that can assist in determining the chemical homogeneity and physical alignment of polymer chains in 3-D printed materials. Two polymers commonly used in 3-D printing, acrylonitrile butadiene styrene (ABS) and polycarbonate (PC), were investigated using 1- and 2-D hyperspectral Raman imaging. In the case of ABS, a complex thermoplastic, the homogeneity of the material through the weld zone was investigated by comparing Raman peaks from each of the three components. In order to investigate the effect of processing conditions on polymer chain alignment, polarized Raman spectroscopy was used. In particular, the print speed or shear rate and effect of strain on PC filaments was investigated with perpendicular and parallel polarizations. National Institute of Standards and Technology Gaithersburg, MD ; Society of Physics Students.

Observation and theory of Pc 5 waves with harmonically related transverse and compressional components

NASA Astrophysics Data System (ADS)

Takahashi, K.; Cheng, C. Z.; McEntire, R. W.; Kistler, L. M.

1990-02-01

The properties of 23 magnetic pulsation events observed by the AMPTE CCE spacecraft are studied. These events are selected on the basis of the field magnitude which oscillated at the second harmonic of a simultaneously present transverse oscillation. The events have a second harmonic period of 80-600 s (roughly the Pc 5 range), are observed in cluster in the dawn (0300-0800 magnetic local time, MLT) and dusk (1600-2100 MLT) sectors, and are localized near the magnetic equator. Although the azimuthal wave number estimated from an ion finite Larmor radius effect, is generally large (about 50), there is a marked difference between the events observed in the dawn and dusk sectors. In the dawn sector the waves have low frequencies (1-5 mHz), indicate left-hand polarization with respect to the ambient magnetic field, and propagate eastward with respect to the spacecraft. In the dusk sector the waves have high frequencies (5-15 mHz), indicate right-hand polarization, and propagate westward. It is suggested that the waves are all westward propagating in the plasma rest frame and that local-time-dependent Doppler shift is the reason for the local time dependence of the wave properties.

Observation and theory of Pc 5 waves with harmonically related transverse and compressional components

NASA Technical Reports Server (NTRS)

Takahashi, K.; Mcentire, R. W.; Cheng, C. Z.; Kistler, L. M.

1990-01-01

The properties of 23 magnetic pulsation events observed by the AMPTE CCE spacecraft are studied. These events are selected on the basis of the field magnitude which oscillated at the second harmonic of a simultaneously present transverse oscillation. The events have a second harmonic period of 80-600 s (roughly the Pc 5 range), are observed in cluster in the dawn (0300-0800 magnetic local time, MLT) and dusk (1600-2100 MLT) sectors, and are localized near the magnetic equator. Although the azimuthal wave number estimated from an ion finite Larmor radius effect, is generally large (about 50), there is a marked difference between the events observed in the dawn and dusk sectors. In the dawn sector the waves have low frequencies (1-5 mHz), indicate left-hand polarization with respect to the ambient magnetic field, and propagate eastward with respect to the spacecraft. In the dusk sector the waves have high frequencies (5-15 mHz), indicate right-hand polarization, and propagate westward. It is suggested that the waves are all westward propagating in the plasma rest frame and that local-time-dependent Doppler shift is the reason for the local time dependence of the wave properties.

BP Piscium: its flaring disc imaged with SPHERE/ZIMPOL★

NASA Astrophysics Data System (ADS)

de Boer, J.; Girard, J. H.; Canovas, H.; Min, M.; Sitko, M.; Ginski, C.; Jeffers, S. V.; Mawet, D.; Milli, J.; Rodenhuis, M.; Snik, F.; Keller, C. U.

2017-03-01

Whether BP Piscium (BP Psc) is either a pre-main sequence T Tauri star at d ≈ 80 pc, or a post-main sequence G giant at d ≈ 300 pc is still not clear. As a first-ascent giant, it is the first to be observed with a molecular and dust disc. Alternatively, BP Psc would be among the nearest T Tauri stars with a protoplanetary disc (PPD). We investigate whether the disc geometry resembles typical PPDs, by comparing polarimetric images with radiative transfer models. Our Very Large Telescope/Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE)/Zurich IMaging Polarimeter (ZIMPOL) observations allow us to perform polarimetric differential imaging, reference star differential imaging, and Richardson-Lucy deconvolution. We present the first visible light polarization and intensity images of the disc of BP Psc. Our deconvolution confirms the disc shape as detected before, mainly showing the southern side of the disc. In polarized intensity the disc is imaged at larger detail and also shows the northern side, giving it the typical shape of high-inclination flared discs. We explain the observed disc features by retrieving the large-scale geometry with MCMAX radiative transfer modelling, which yields a strongly flared model, atypical for discs of T Tauri stars.

Dynamics of influence and social balance in spatially-embedded regular and random networks

NASA Astrophysics Data System (ADS)

Singh, P.; Sreenivasan, S.; Szymanski, B.; Korniss, G.

2015-03-01

Structural balance - the tendency of social relationship triads to prefer specific states of polarity - can be a fundamental driver of beliefs, behavior, and attitudes on social networks. Here we study how structural balance affects deradicalization in an otherwise polarized population of leftists and rightists constituting the nodes of a low-dimensional social network. Specifically, assuming an externally moderating influence that converts leftists or rightists to centrists with probability p, we study the critical value p =pc , below which the presence of metastable mixed population states exponentially delay the achievement of centrist consensus. Above the critical value, centrist consensus is the only fixed point. Complementing our previously shown results for complete graphs, we present results for the process on low-dimensional networks, and show that the low-dimensional embedding of the underlying network significantly affects the critical value of probability p. Intriguingly, on low-dimensional networks, the critical value pc can show non-monotonicity as the dimensionality of the network is varied. We conclude by analyzing the scaling behavior of temporal variation of unbalanced triad density in the network for different low-dimensional network topologies. Supported in part by ARL NS-CTA, ONR, and ARO.

Polymer photonic crystal slab waveguides

NASA Astrophysics Data System (ADS)

Liguda, C.; Böttger, G.; Kuligk, A.; Blum, R.; Eich, M.; Roth, H.; Kunert, J.; Morgenroth, W.; Elsner, H.; Meyer, H. G.

2001-04-01

We present details of the fabrication, calculations, and transmission measurements for finite two-dimensional (2D) polymer photonic crystal (PC) slab waveguides, which were fabricated from a benzocyclobutene polymer on a low refractive index substrate from Teflon. A square air hole lattice (500 nm lattice constant, 300 nm hole diameter) was realized by electron beam lithography and reactive ion etching. Polarization and wavelength dependent transmission results show TE-like and TM-like stop gaps at 1.3 μm excitation wavelengths and are in good agreement with the calculated data obtained by 2D and three-dimensional finite difference time domain methods. Transmission was suppressed by 15 dB in the center of the TE-like stop gap for a PC length of ten lattice constants.

Dietary food groups intake and cooking methods associations with pancreatic cancer: a case-control study.

PubMed

Ghorbani, Zeinab; Hekmatdoost, Azita; Zinab, Hassan Eini; Farrokhzad, Solmaz; Rahimi, Roya; Malekzadeh, Reza; Pourshams, Akram

2015-05-01

The role of dietary habits in the etiology of pancreatic cancer (PC) has not yet been well elucidated. The aim of the present study was to examine the association of the frequency of different food groups' intake and their cooking methods with PC risk based on a well-designed case-control study. A case-control study including 307 PC patients and 322 controls referred to four tertiary endosonography centers was conducted from January 2011 to January 2014 to compare the frequency intake of different food items and their cooking methods between cases and controls. After adjustment for gender, age, body mass index, years of education, diabetes and alcohol history, smoking status, and opium use, a significant direct relationship was observed between PC risk and intake frequency (time/week) of bread (OR = 1.50; 95 % CI 1.05-2.13; p-value 0.024), rice (OR = 2.10; 95 % CI 1.15-3.82; p for trend 0.034), and red meat (OR = 2.25; 95 % CI 1.22-4.14; p for trend 0.033) (time/day), when comparing the highest category of intake frequency with the lowest, while increasing frequency of fish consumption was associated with a lower risk of PC (OR = 0.93; 95 % CI0.59-1.47; p for trend 0.009). Increasing consumption of barbecuing red meat and deep fried vegetables was associated with 67 % and 70 % increased risk of PC (p-value 0.025 and 0.006, respectively). Our results indicate that increased frequency of intake of bread, rice, and red meat (especially barbecued) and deep fried vegetables can aggregate PC risk, while increased frequency of fish consumption can protect against PC. However, more studies are still needed.

Polarization of seven MBM clouds at high Galactic latitude

NASA Astrophysics Data System (ADS)

Neha, S.; Maheswar, G.; Soam, A.; Lee, C. W.

2018-06-01

We made R-band polarization measurements of 234 stars towards the direction of the MBM 33-39 cloud complex. The distance of the MBM 33-39 complex was determined as 120 ± 10 pc using polarization results and near-infrared photometry from the 2MASS survey. The magnetic field geometry of the individual clouds inferred from our polarimetric results reveals that the field lines are in general consistent with the global magnetic field geometry of the region obtained from previous studies. This implies that the clouds in the complex are permeated by the interstellar magnetic field. Multi-wavelength polarization measurements of a few stars projected on to the complex suggest that the size of the dust grains in these clouds is similar to those found in the normal interstellar medium of the Milky Way. We studied a possible formation scenario of the MBM 33-39 complex by combining the polarization results from our study with those from the literature and by identifying the distribution of ionized, atomic and molecular (dust) components of material in the region.

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_IM_KP_0161

NASA Technical Reports Server (NTRS)

Ocuna, M. H.; Ogilvie, K. W.; Baker, D. N.; Curtis, S. A.; Fairfield, D. H.; Mish, W. H.

2000-01-01

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0192

NASA Technical Reports Server (NTRS)

Ocuna, M. H.; Ogilvie, K. W.; Baker, D. N.; Curtis, S. A.; Fairfield, D. H.; Mish, W. H.

2001-01-01

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0139

NASA Technical Reports Server (NTRS)

Ocuna, M. H.; Ogilvie, K. W.; Baker, D. N.; Curtis, S. A.; Fairfield, D. H.; Mish, W. H.

1999-01-01

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_IM_KP_0185

NASA Technical Reports Server (NTRS)

Ocuna, M. H.; Ogilvie, K. W.; Baker, D. N.; Curtis, S. A.; Fairfield, D. H.; Mish, W. H.

2000-01-01

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Surface modification of a biodegradable magnesium alloy with phosphorylcholine (PC) and sulfobetaine (SB) functional macromolecules for reduced thrombogenicity and acute corrosion resistance

PubMed Central

Ye, Sang-Ho; Jang, Yong-Seok; Yun, Yeo-Heung; Shankarraman, Venkat; Woolley, Joshua R.; Hong, Yi; Gamble, Lara J.; Ishihara, Kazuhiko; Wagner, William R.

2013-01-01

Siloxane functionalized phosphorylcholine (PC) or sulfobetaine (SB) macromolecules (PCSSi or SBSSi) were synthesized to act as surface modifying agents for degradable metallic surfaces to improve acute blood compatibility and slow initial corrosion rates. The macromolecules were synthesized using a thiol-ene radical photopolymerization technique and then utilized to modify magnesium (Mg) alloy (AZ31) surfaces via an anhydrous phase deposition of the silane functional groups. X-ray photoelectron spectroscopy surface analysis results indicated successful surface modification based on increased nitrogen and phosphorus or sulfur composition on the modified surfaces relative to unmodified AZ31. In vitro acute thrombogenicity assessment after ovine blood contact with the PCSSi and SBSSi modified surfaces showed a significant decrease in platelet deposition and bulk phase platelet activation compared with the control alloy surfaces. Potentiodynamic polarization and electrochemical impedance spectroscopy data obtained from electrochemical corrosion testing demonstrated increased corrosion resistance for PCSSi and SBSSi modified AZ31 versus unmodified surfaces. The developed coating technique using PCSSi or SBSSi showed promise in acutely reducing both the corrosion and thrombotic processes, which would be attractive for application to blood contacting devices, such as vascular stents, made from degradable Mg alloys. PMID:23705967

76 FR 17164 - Notice of Request for a Revision of a Currently Approved Information Collection and Request for a...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-28

... Status Review form (PC 1789); the Report of Medical Exam (PC 1790 S); and, Dental Exam (PC 1790). The Peace Corps wants to remove the Dental Exam (PC 1790) from OMB 0420- 0510 and request a new OMB Control Number for Dental Exam (PC 1790). This process is conducted in accordance with 5 CFR 1320.10. DATES...

76 FR 33374 - Notice of Request for a Revision of a Currently Approved Information Collection and Request for a...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-08

... Review form (PC 1789); the Report of Medical Exam (PC 1790 S); and, Dental Exam (PC 1790). The Peace Corps wants to remove the Dental Exam (PC 1790) from OMB 0420- 0510 and request a new OMB Control Number for Dental Exam (PC 1790). This process is conducted in accordance with 5 CFR 1320.10. DATES: Comments...

History of gonorrhea and prostate cancer in a population-based case-control study in Mexico.

PubMed

Vázquez-Salas, Ruth Argelia; Torres-Sánchez, Luisa; López-Carrillo, Lizbeth; Romero-Martínez, Martín; Manzanilla-García, Hugo A; Cruz-Ortíz, Carlos Humberto; Mendoza-Peña, Fernando; Jiménez-Ríos, Miguel Ángel; Rodríguez-Covarrubias, Francisco; Hernández-Toríz, Narciso; Moreno-Alcázar, Othón

2016-02-01

We evaluated the association between a history of sexually transmitted diseases (STDs) and the risk for prostate cancer (PC) among Mexican males. PC incident cases (n=402) that were identified at six public hospitals in Mexico City were matched by age (±5 years) with 805 population controls with no history of PC. By face-to-face interview, we obtained information about sexual history, previous STDs, sociodemographic characteristics, and familial history of PC. An unconditional logistic regression model was used to estimate the risk for PC. A total of 16.6% of men reported having had at least one previous STD, and the most frequently reported STD was gonorrhea (10.5%). After adjusting by PC familial history, the history of STD was associated with a two-fold greater risk of PC: odds ratio (OR)=2.67; 95% confidence interval (95% CI=1.91-3.73). When each STD was evaluated separately, only gonorrhea was associated with a significant increase in PC risk (OR=3.04; 95% CI=1.99-4.64). These associations were similar when we stratified by low-risk PC (Gleason <7) and high-risk PC (Gleason ≥7). These results confirm that STDs, and particularly gonorrhea, may play an etiological role in PC among Mexican males, which is consistent with a previous report from a multiethnic cohort. Copyright © 2015 Elsevier Ltd. All rights reserved.

A simple and sensitive method to measure timing accuracy.

PubMed

De Clercq, Armand; Crombez, Geert; Buysse, Ann; Roeyers, Herbert

2003-02-01

Timing accuracy in presenting experimental stimuli (visual information on a PC or on a TV) and responding (keyboard presses and mouse signals) is of importance in several experimental paradigms. In this article, a simple system for measuring timing accuracy is described. The system uses two PCs (at least Pentium II, 200 MHz), a photocell, and an amplifier. No additional boards and timing hardware are needed. The first PC, a SlavePC, monitors the keyboard presses or mouse signals from the PC under test and uses a photocell that is placed in front of the screen to detect the appearance of visual stimuli on the display. The software consists of a small program running on the SlavePC. The SlavePC is connected through a serial line with a second PC. This MasterPC controls the SlavePC through an ActiveX control, which is used in a Visual Basic program. The accuracy of our system was investigated by using a similar setup of a SlavePC and a MasterPC to generate pulses and by using a pulse generator card. These tests revealed that our system has a 0.01-msec accuracy. As an illustration, the reaction time accuracy of INQUISIT for a few applications was tested using our system. It was found that in those applications that we investigated, INQUISIT measures reaction times from keyboard presses with millisecond accuracy.

NIR camera and spectrograph SWIMS for TAO 6.5m telescope: array control system and its performance

NASA Astrophysics Data System (ADS)

Terao, Yasunori; Motohara, Kentaro; Konishi, Masahiro; Takahashi, Hidenori; Kato, Natsuko M.; Kitagawa, Yutaro; Kobayakawa, Yutaka; Ohashi, Hirofumi; Tateuchi, Ken; Todo, Soya

2016-08-01

SWIMS (Simultaneous-color Wide-field Infrared Multi-object Spectrograph) is a near-infrared imager and multi-object spectrograph as one of the first generation instruments for the University of Tokyo Atacama Observatory (TAO) 6.5m telescope. In this paper, we describe an array control system of SWIMS and results of detector noise performance evaluation. SWIMS incorporates four (and eight in future) HAWAII-2RG focal plane arrays for detectors, each driven by readout electronics components: a SIDECAR ASIC and a JADE2 Card. The readout components are controlled by a HAWAII-2RG Testing Software running on a virtual Windows machine on a Linux PC called array control PC. All of those array control PCs are then supervised by a SWIMS control PC. We have developed an "array control software system", which runs on the array control PC to control the HAWAII-2RG Testing Software, and consists of a socket client and a dedicated server called device manager. The client runs on the SWIMS control PC, and the device manager runs on the array control PC. An exposure command, issued by the client on the SWIMS control PC, is sent to the multiple device managers on the array control PCs, and then multiple HAWAII-2RGs are driven simultaneously. Using this system, we evaluate readout noise performances of the detectors, both in a test dewar and in a SWIMS main dewar. In the test dewar, we confirm the readout noise to be 4.3 e- r.m.s. by 32 times multiple sampling when we operate only a single HAWAII-2RG, whereas in the case of simultaneous driving of two HAWAII-2RGs, we still obtain sufficiently low readout noise of 10 e- r.m.s. In the SWIMS main dewar, although there are some differences between the detectors, the readout noise is measured to be 4:1-4:6 e- r.m.s. with simultaneous driving by 64 times multiple sampling, which meets the requirement for background-limited observations in J band of 14 e- r.m.s..

All n-3 PUFA are not the same: MD simulations reveal differences in membrane organization for EPA, DHA and DPA.

PubMed

Leng, Xiaoling; Kinnun, Jacob J; Cavazos, Andres T; Canner, Samuel W; Shaikh, Saame Raza; Feller, Scott E; Wassall, Stephen R

2018-05-01

Eicosapentaenoic (EPA, 20:5), docosahexaenoic (DHA, 22:6) and docosapentaenoic (DPA, 22:5) acids are omega-3 polyunsaturated fatty acids (n-3 PUFA) obtained from dietary consumption of fish oils that potentially alleviate the symptoms of a range of chronic diseases. We focus here on the plasma membrane as a site of action and investigate how they affect molecular organization when taken up into a phospholipid. All atom MD simulations were performed to compare 1-stearoyl-2-eicosapentaenoylphosphatylcholine (EPA-PC, 18:0-20:5PC), 1-stearoyl-2-docosahexaenoylphosphatylcholine (DHA-PC, 18:0-22:6PC), 1-stearoyl-2-docosapentaenoylphosphatylcholine (DPA-PC, 18:0-22:5PC) and, as a monounsaturated control, 1-stearoyl-2-oleoylphosphatidylcholine (OA-PC, 18:0-18:1PC) bilayers. They were run in the absence and presence of 20mol% cholesterol. Multiple double bonds confer high disorder on all three n-3 PUFA. The different number of double bonds and chain length for each n-3 PUFA moderates the reduction in membrane order exerted (compared to OA-PC, S¯ CD =0.152). EPA-PC (S¯ CD =0.131) is most disordered, while DPA-PC (S¯ CD =0.140) is least disordered. DHA-PC (S¯ CD =0.139) is, within uncertainty, the same as DPA-PC. Following the addition of cholesterol, order in EPA-PC (S¯ CD =0.169), DHA-PC (S¯ CD =0.178) and DPA-PC (S¯ CD =0.182) is increased less than in OA-PC (S¯ CD =0.214). The high disorder of n-3 PUFA is responsible, preventing the n-3 PUFA-containing phospholipids from packing as close to the rigid sterol as the monounsaturated control. Our findings establish that EPA, DHA and DPA are not equivalent in their interactions within membranes, which possibly contributes to differences in clinical efficacy. Copyright © 2018 Elsevier B.V. All rights reserved.

Performance Contracting and Quality Improvement in Outpatient Treatment: Effects on Waiting Time and Length of Stay

PubMed Central

Stewart, Maureen T.; Horgan, Constance M.; Garnick, Deborah W.; Ritter, Grant; McLellan, A. Thomas

2012-01-01

We evaluate effects of a performance contract (PC) implemented in Delaware in 2001 and participation in quality improvement (QI) programs on waiting time for treatment and length of stay (LOS) using client treatment episode level data from Delaware (n = 12,368) and Maryland (n = 147,151) for 1998 – 2006. Results of difference-in-difference analyses indicate waiting time declined 13 days following the PC, after controlling for client characteristics and historical trends. Participation in the PC and a formal QI program was associated with a decrease of 20 days. LOS increased 22 days under the PC and 24 days under the PC and QI programs, after controlling for client characteristics. The PC and QI program were associated with improvements in LOS and waiting time, although we cannot determine which aspects of the programs (incentives, training, monitoring) resulted in these changes. PMID:22445031

[A skin cell segregating control system based on PC].

PubMed

Liu, Wen-zhong; Zhou, Ming; Zhang, Hong-bing

2005-11-01

A skin cell segregating control system based on PC (personal computer) is presented in this paper. Its front controller is a single-chip microcomputer which enables the manipulation for 6 patients simultaneously, and thus provides a great convenience for clinical treatments for vitiligo. With the use of serial port communication technology, it's possible to monitor and control the front controller in a PC terminal. And the application of computer image acquisition technology realizes the synchronous acquisition of pathologic shin cell images pre/after the operation and a case history. Clinical tests prove its conformity with national standards and the pre-set technological requirements.

Automatic control of a negative ion source

NASA Astrophysics Data System (ADS)

Saadatmand, K.; Sredniawski, J.; Solensten, L.

1989-04-01

A CAMAC based control architecture is devised for a Berkeley-type H - volume ion source [1]. The architecture employs three 80386 TM PCs. One PC is dedicated to control and monitoring of source operation. The other PC functions with digitizers to provide data acquisition of waveforms. The third PC is used for off-line analysis. Initially, operation of the source was put under remote computer control (supervisory). This was followed by development of an automated startup procedure. Finally, a study of the physics of operation is now underway to establish a data base from which automatic beam optimization can be derived.

Magnetization distribution and spin transport of graphene/h-BN/graphene nanoribbon-based magnetic tunnel junction

NASA Astrophysics Data System (ADS)

Zhang, Y.; Yan, X. H.; Guo, Y. D.; Xiao, Y.

2017-09-01

Motivated by recent electronic transport measurement of boron nitride-graphene hybrid atomic layers, we studied magnetization distribution, transmission and current-bias relation of graphene/h-BN/graphene (C/BN/C) nanoribbon-based magnetic tunnel junctions (MTJ) based on density functional theory and non-equilibrium Green's function methods. Three types of MTJs, i.e. asymmetric, symmetric (S) and symmetric (SS), and two types of lead magnetization alignment, i.e. parallel (PC) and antiparallel (APC), are considered. The results show that the magnetization distribution is closely related to the interface structure. Especially for asymmetric MTJ, the B/N atoms at the C/BN interface are spin-polarized and give finite magnetic moments. More interesting, it is found that the APC transmission of asymmetric MTJ with the thinnest barrier dominates over the PC one. By analyzing the projected density of states, one finds that the unusual higher APC transmission than PC is due to the coupling of electronic states of left ZGNR and right ZGNR. By integrating transmission, we calculate the current-bias voltage relation and find that the APC current is larger than PC current at small bias voltage and therefore reproduces a negative tunnel magnetoresistance. The results reported here will be useful and important for the design of C/BN/C-based MTJ.

Contrast Enhanced Microscopy Digital Image Correlation: A General Method to Contact-Free Coefficient of Thermal Expansion Measurement of Polymer Films

Treesearch

Jairo A. Diaz; Robert J. Moon; Jeffrey P. Youngblood

2014-01-01

Thermal expansion represents a vital indicator of the processing history and dimensional stability of materials. Solvent-sensitive, thin, and compliant samples are particularly challenging to test. Here we describe how textures highlighted by contrast enhanced optical microscopy modes (i.e., polarized light (PL), phase contrast (PC)) and bright field (BF) can be used...

An Intervention to Control Vasomotor Symptoms for Advanced PC Patients on Hormone Therapy

DTIC Science & Technology

2014-08-01

Symptoms for Advanced PC Patients on Hormone Therapy PRINCIPAL INVESTIGATOR: Michael A. Diefenbach, Ph.D. CONTRACTING ORGANIZATION...Control Vasomotor Symptoms for Advanced PC Patients on Hormone Therapy 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-11-1-0604 5c...NOTES 14. ABSTRACT Vasomotor Symptom (Hot Flashes) is a common side-effect of hormone therapy for prostate cancer survivors who experience a rising

Role of adipocytokines and its correlation with endocrine pancreatic function in patients with pancreatic cancer.

PubMed

Gąsiorowska, Anita; Talar-Wojnarowska, Renata; Kaczka, Aleksandra; Borkowska, Anna; Czupryniak, Leszek; Małecka-Panas, Ewa

2013-01-01

Some authors suggest that adipocytokines contribute to the induction of pancreatic carcinogenesis as well as the development of endocrine insufficiency. We evaluate the circulating concentrations of leptin, resistin and visfatin in patients with newly diagnosed pancreatic cancer (PC) and relationship between serum adipocytokines level and clinicopathological features of PC. Moreover the usefulness of those adipocytokines as possible biomarkers of endocrine pancreatic function in PC has been assessed. The pilot study group consisted of 45 individuals (mean age 65.6 ± 11.5 years, BMI 21.8 ± 3.4 kg/m(2)) with newly diagnosed PC (within last 1-3 months) and 13 healthy individuals with age, gender and BMI matched to the study group. Among PC patients 18 (40%) had recently diagnosed diabetes. Fasting plasma leptin, resistin, visfatin concentrations were determined with ELISA (R&D Systems, Phoenix Pharmaceuticals) and insulin by RIA (DakoCytomation). Patients with PC as compared to controls had significantly lower plasma leptin (40.6 ± 21.3 vs 63.2 ± 16.3 pg/mL; p < 0,0008). In contrast PC patients showed more than six fold higher level of resistin (126.2 ± 143.2 vs 18.9 ± 7.2 ng/mL; p < 0.009) than controls. The median plasma visfatin was 2.8 ± 1.8 ng/mL, which was not significantly different from the controls (3.8 ± 1.1 ng/mL). When PC patients with and without diabetes were considered separately, plasma leptin concentrations among nondiabetic patients were slightly, but not significantly higher (44.6 ± 21.0) as compared to diabetics (34.5 ± 20.7). Moreover there was no difference between visfatin and resistin level in PC, among patients with and without diabetes. No significant differences between serum level of leptin, visfatin and resistin and age, gender, BMI, smoking status, tumor localization, distant metastases and pain has been found. The results of this study confirm previous findings that patients with newly diagnosed pancreatic cancer are characterized with lower level of leptin. This pilot study showed significantly higher resistin concentrations in patients with PC in comparison to healthy controls, which may be helpful in PC early diagnosis. Changes in leptin and resistin level in PC are not likely related to endocrine disorders. Copyright © 2013 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Hierarchical nanostructures of copper(II) phthalocyanine on electrospun TiO(2) nanofibers: controllable solvothermal-fabrication and enhanced visible photocatalytic properties.

PubMed

Zhang, Mingyi; Shao, Changlu; Guo, Zengcai; Zhang, Zhenyi; Mu, Jingbo; Cao, Tieping; Liu, Yichun

2011-02-01

In the present work, 2,9,16,23-tetranitrophthalocyanine copper(II) (TNCuPc)/TiO(2) hierarchical nanostructures were successfully fabricated by a simple combination method of electrospinning technique and solvothermal processing. Scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, X-ray diffraction (XRD), UV-vis diffuse reflectance (DR), Fourier transform infrared spectrum (FT-IR), X-ray photoelectron spectroscopy (XPS), and thermal gravimetric and differential thermal analysis (TG-DTA) were used to characterize the as-synthesized TNCuPc/TiO(2) hierarchical nanostructures. The results showed that the secondary TNCuPc nanostructures were not only successfully grown on the primary TiO(2) nanofibers substrates but also uniformly distributed without aggregation. By adjusting the solvothermal fabrication parameters, the TNCuPc nanowires or nanoflowers were facilely fabricated, and also the loading amounts of TNCuPc could be controlled on the TNCuPc/TiO(2) hierarchical nanostructural nanofibers. And, there might exist the interaction between TNCuPc and TiO(2). A possible mechanism for the formation of TNCuPc/TiO(2) hierarchical nanostructures was suggested. The photocatalytic studies revealed that the TNCuPc/TiO(2) hierarchical nanostructures exhibited enhanced photocatalytic efficiency of photodegradation of Rhodamine B (RB) compared with the pure TNCuPc or TiO(2) nanofibers under visible-light irradiation.

Correlations between serum trypsinogen-2 and pancreatic cancer.

PubMed

Cao, Jianbiao; Xia, Changhong; Cui, Tingting; Guo, Hanbin; Li, Haoran; Ren, Yongqiang; Wang, Shuai

2015-01-01

To investigate associations be- tween serum trypsinogen-2, pancreatitis and pancreatic cancer (PC) and determine cutoff values for PC diagnosis. We recruited 88 patients from Internal Medicine/Surgical Departments of General Military Hospital of Beijing PLA between 12/2009 and 6/2010. Serum samples were collected preoperatively from 23 PC patients, 30 pancreatitis patients and 35 healthy controls. Enzyme-linked immunosorbent assay was used to detect trypsinogen-2 semiquantitatively. Serum trypsinogen-2 levels of PC and pancreatitis patients were significantly higher than those of controls (51.2 ± 80.3, 107.7 ± 98.1 vs. 1.0 ± 0.5, p = 0.03, p < 0.001) and significantly higher in pancreatitis vs. PC patients (107.7 ± 98.1 vs. 51.2 ± 80.3, p = 0.01). Higher Balthazar CT grades correlated with higher trypsinogen-2 in pancreatitis group. ROC curves for trypsinogen-2 revealed optimal cutoff value 1.8 as lower PC detection limit with 95.7% sensitivity and 91.4% specificity, and optimal cutoff value 19.9 for upper PC detection limit with 87.0% sensitivity and 97.1% specificity. Trypsinogen-2 levels correlated with pancreatic injury level. An AUC of 0.73 (95% Cl: 0.59-0.84, p = 0.002) distinguished PC from pancreatitis. Serum trypsinogen-2 is associated with PC and pancreatitis. Levels between 1.8 μg/L and 19.9 μg/L strongly suggest PC. Detection of serum trypsinogen-2 may provide simple, sensitive, specific non-invasive initial screening for early PC diagnosis.

Diet, Lifestyles, Family History, and Prostate Cancer Incidence in an East Algerian Patient Group

PubMed Central

Lassed, Somia; Deus, Cláudia M.; Lourenço, Nuno; Dahdouh, Abderrezak

2016-01-01

Prostate cancer (PC) is the fourth most common cancer in men and the sixth leading cause of death in Algeria. To examine the relationship between lifestyle factors, including diet, and family history and PC risk, a case-control study was performed in an eastern Algerian population, comprising 90 patients with histologically confirmed PC and 190 controls. Data collection was carried out through a structured questionnaire and statistical analysis was performed to evaluate the different variables. The data showed that consumption of lamb and beef meat and high intake of animal fat and dairy products increased PC risk. Seven to thirteen vegetables servings per week and fourteen or more servings decreased PC risk by 62% and 96%, respectively. Seven to fourteen fruit servings per week decrease PC risk by 98%. Green tea consumption reduced the risk of PC but the results were statistically borderline. Increased risk was observed for individuals with family history of PC in first and in second degree. A positive strong association was also found for alcohol and smoking intake and a dose-response relationship existed for quantity and history of smoking. This study suggests that dietary habits, lifestyle factors, and family history have influence on the development of PC in Algerian population. PMID:27975054

Assessing fears of preschool children with nighttime fears by a parent version of the fear survey schedule for preschool children.

PubMed

Kushnir, Jonathan; Gothelf, Doron; Sadeh, Avi

2015-01-01

Although excessive fears are common in preschool children, validated assessment tools for this age are lacking. Our aim was to modify and provide preliminary evidence of the utility of a preschoolers' fear screening tool, a parent-reported Fear Survey Schedule for Preschool Children (FSS-PC). 109 Israeli preschool children (aged 4-6 years) with chronic night time fears (NF) and 30 healthy children (controls) participated. The FSS-PC analysis included: 1) internal reliability, 2) correlations between FSS-PC scores and Child Behavior Checklist (CBCL) measures, 3) differences between NF and a comparison sample of FSS-PC scores, and 4) FSS-PC sensitivity in detecting change in NF following an intervention for NF. There were low-to-medium positive correlations between the FSS-PC scores and several internalizing scales of the CBCL measures. FSS-PC scores in the NF group were significantly higher than the control children's score. FSS-PC scores had adequate internal reliability and were also sensitive for detecting significant changes in fear levels following behavioral interventions. Unique cultural and environmental circumstances and specific study group. This new version of the FSS-PC may provide clinicians with a novel and useful screening tool for early assessment of fear- and anxiety-related phenomena of preschool children.

Diet, Lifestyles, Family History, and Prostate Cancer Incidence in an East Algerian Patient Group.

PubMed

Lassed, Somia; Deus, Cláudia M; Lourenço, Nuno; Dahdouh, Abderrezak; Rizvanov, Albert A; Oliveira, Paulo J; Zama, Djamila

2016-01-01

Prostate cancer (PC) is the fourth most common cancer in men and the sixth leading cause of death in Algeria. To examine the relationship between lifestyle factors, including diet, and family history and PC risk, a case-control study was performed in an eastern Algerian population, comprising 90 patients with histologically confirmed PC and 190 controls. Data collection was carried out through a structured questionnaire and statistical analysis was performed to evaluate the different variables. The data showed that consumption of lamb and beef meat and high intake of animal fat and dairy products increased PC risk. Seven to thirteen vegetables servings per week and fourteen or more servings decreased PC risk by 62% and 96%, respectively. Seven to fourteen fruit servings per week decrease PC risk by 98%. Green tea consumption reduced the risk of PC but the results were statistically borderline. Increased risk was observed for individuals with family history of PC in first and in second degree. A positive strong association was also found for alcohol and smoking intake and a dose-response relationship existed for quantity and history of smoking. This study suggests that dietary habits, lifestyle factors, and family history have influence on the development of PC in Algerian population.

KSC-98pc1230

NASA Image and Video Library

1998-10-03

KENNEDY SPACE CENTER, FLA. -- In the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2), the top of the Mars Polar Lander is removed for testing, which includes a functional test of the science instruments and the basic spacecraft subsystems. The Mars Polar Lander is targeted for launch from Cape Canaveral Air Station aboard a Delta II rocket on Jan. 3, 1999. The solar-powered spacecraft is designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere

KSC-98pc1197

NASA Image and Video Library

1998-10-01

KENNEDY SPACE CENTER, FLA. -- At the Shuttle Landing Facility, the Mars Polar Lander is rolled from the Air Force C-17 cargo plane that carried it from the Lockheed Martin Astronautics plant in Denver, CO. The Mars Polar Lander is targeted for launch from Cape Canaveral Air Station aboard a Delta II rocket on Jan. 3, 1999. The solar-powered spacecraft is designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere

KSC-98pc1231

NASA Image and Video Library

1998-10-03

KENNEDY SPACE CENTER, FLA. -- In the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2), the Mars Polar Lander is secured on a workstand for testing, which includes a functional test of the science instruments and the basic spacecraft subsystems. The Mars Polar Lander is targeted for launch from Cape Canaveral Air Station aboard a Delta II rocket on Jan. 3, 1999. The solar-powered spacecraft is designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere

KSC-98pc1235

NASA Image and Video Library

1998-10-03

KENNEDY SPACE CENTER, FLA. -- In the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2), a technician begins testing on the Mars Polar Lander. The checkout includes a functional test of the science instruments and the basic spacecraft subsystems. The Mars Polar Lander is targeted for launch from Cape Canaveral Air Station aboard a Delta II rocket on Jan. 3, 1999. The solar-powered spacecraft is designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere

Observations of a Unique Type of ULF Waves by Low-Latitude Space Technology Five Mission

NASA Technical Reports Server (NTRS)

Le, G.; Chi, P.; Strangeway, R. J.; Slavin, J. A.

2011-01-01

We report a unique type of ULF waves observed by low-altitude Space Technology 5 (ST-5) constellation mission. ST-5 is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, and sun synchronous polar orbit with 105.6deg inclination angle. Due to the Earth s rotation and the dipole tilt effect, the spacecraft s dawn-dusk orbit track can reach as low as subauroral latitudes during the course of a day. Whenever the spacecraft traverse across the dayside closed field line region at subauroral latitudes, they frequently observe strong transverse oscillations at 30-200 mHz, or in the Pc 2-3 frequency range. These Pc 2-3 waves appear as wave packets with durations in the order of 5-10 minutes. As the maximum separations of the ST-5 spacecraft are in the order of 10 minutes, the three ST-5 satellites often observe very similar wave packets, implying these wave oscillations occur in a localized region. The coordinated ground-based magnetic observations at the spacecraft footprints, however, do not see waves in the Pc 2-3 band; instead, the waves appear to be the common Pc 4-5 waves associated with field line resonances. We suggest that these unique Pc 2-3 waves seen by ST-5 are in fact the Doppler-shifted Pc 4-5 waves as a result of rapid traverse of the spacecraft across the resonant field lines azimuthally at low altitudes. The observations with the unique spacecraft dawn-disk orbits at proper altitudes and magnetic latitudes reveal the azimuthal characteristics of field-aligned resonances.

Formation of phosphatidylethanol from endogenous phosphatidylcholines in animal tissues from pig, calf, and goat.

PubMed

Luginbühl, Marc; Willem, Sytske; Schürch, Stefan; Weinmann, Wolfgang

2018-02-01

In the presence of alcohol, phosphatidylcholine (PC) is transformed to the direct alcohol biomarker phosphatidylethanol (PEth). This reaction is catalyzed by the enzyme phospholipase D (PLD) and dependent on substrate availability. As recent methods have solely focused on the determination of PEth, information about the PC composition was generally missing. To address this issue and monitor PC (16:0/18:1 and 16:0/18:2) and PEth (16:0/18:1 and 16:0/18:2) simultaneously, a reversed phase LC-MS/MS method based on a C8 core-shell column, coupled to a Sciex 5500 QTrap instrument was developed. By application of polarity switching, at first, PC was measured in ESI positive SRM mode, while PEth was determined at a later stage in ESI negative SRM mode. The PEth method was validated for human blood samples to show its robustness and subsequently applied for the investigation of systematic in vitro PEth formation in animal tissue samples (brain, kidney, liver, and blood) from a pig, a calf, and a goat. Homogenized tissue was incubated at 37°C with varying ethanol concentrations from 1 to 7g/kg (determined by HS-GC-FID) for 5h, whereby a sample was taken every 30min. For all tissue samples, an increase in PEth was measurable. PEth concentrations formed in blood remained below the LLOQ, in agreement with literature. Data analysis of Michaelis-Menten kinetics and PC within the tissue provided a detailed insight about PEth formation, as the occurrence of PEth species can be linked to the observed PC composition. The results of this study show that PEth formation rates vary from tissue to tissue and among different species. Furthermore, new recommendations for PEth analysis are presented. Copyright © 2018 Elsevier B.V. All rights reserved.

Observations of a Unique Type of ULF Waves by Low-Latitude Space Technology 5 Satellites

NASA Technical Reports Server (NTRS)

Le, G.; Chi, P. J.; Strangeway, R. J.; Slavin, J. A.

2011-01-01

We report a unique type of ULF waves observed by low-altitude Space Technology 5 (ST-5) constellation mission. ST-5 is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, and sun synchronous polar orbit with 105.6deg inclination angle. Due to the Earth s rotation and the dipole tilt effect, the spacecraft s dawn-dusk orbit track can reach as low as subauroral latitudes during the course of a day. Whenever the spacecraft traverse across the dayside closed field line region at subauroral latitudes, they frequently observe strong transverse oscillations at 30-200 mHz, or in the Pc 2-3 frequency range. These Pc 2-3 waves appear as wave packets with durations in the order of 5-10 minutes. As the maximum separations of the ST-5 spacecraft are in the order of 10 minutes, the three ST-5 satellites often observe very similar wave packets, implying these wave oscillations occur in a localized region. The coordinated ground-based magnetic observations at the spacecraft footprints, however, do not see waves in the Pc 2-3 band; instead, the waves appear to be the common Pc 4-5 waves associated with field line resonances. We suggest that this unique Pc 2-3 waves seen by ST-5 are in fact the Doppler-shifted Pc 4-5 waves as a result of rapid traverse of the spacecraft across the resonant field lines azimuthally at low altitudes. The observations with the unique spacecraft dawn-disk orbits at proper altitudes and magnetic latitudes reveal the azimuthal characteristics of field-aligned resonances.

Observations of a Unique Type of ULF Waves by Low-Latitude Space Technology 5 Mission

NASA Technical Reports Server (NTRS)

Le, Guan; Chi, P.; Strangeway, R. J.; Slavin, J. A.

2011-01-01

We report a unique type of ULF waves observed by low-altitude Space Technology 5 (ST-5) constellation mission. ST-5 is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, and sun synchronous polar orbit with 105.6 inclination angle. Due to the Earth's rotation and the dipole tilt effect, the spacecraft's dawn-dusk orbit track can reach as low as sub auroral latitudes during the course of a day. Whenever the spacecraft traverse across the dayside closed field line region at sub auroral latitudes, they frequently observe strong transverse oscillations at 30-200 mHz, or in the Pc 2-3 frequency range. These Pc 2-3 waves appear as wave packets with durations in the order of 5-10 minutes. As the maximum separations of the ST-5 spacecraft are in the order of 10 minutes, the three ST -5 satellites often observe very similar wave packets, implying these wave oscillations occur in a localized region. The coordinated ground-based magnetic observations at the spacecraft footprints, however, do not see waves in the Pc 2-3 band; instead, the waves appear to be the common Pc 4-5 waves associated with field line resonances. We suggest that these unique Pc 2-3 waves seen by ST-5 are in fact the Doppler-shifted Pc 4-5 waves as a result of rapid traverse of the spacecraft across the resonant field lines azimuthally at low altitudes. The observations with the unique spacecraft dawn-disk orbits at proper altitudes and magnetic latitudes reveal the azimuthal characteristics of field-aligned resonances.

Observations of a Unique Type of ULF Waves by Low-Latitude Space Technology 5 Mission

NASA Technical Reports Server (NTRS)

Le, G.; Chi, P.; Strangeway, R. J.; Slavin, J. A.

2010-01-01

We report a unique type of ULF waves observed by low-altitude Space Technology 5 (ST-5) constellation mission. ST-5 is a three micro-satellite constellation deployed into a 300 x 4500 km, dawn-dusk, and sun synchronous polar orbit with 105.6 degree inclination angle. Due to the Earth's rotation and the dipole tilt effect, the spacecraft's dawn-dusk orbit track can reach as low as subauroral latitudes during the course of a day. Whenever the spacecraft traverse across the dayside closed field line region at sub auroral latitudes, they frequently observe strong transverse oscillations at 30-200 mHz, or in the Pc 2-3 frequency range. These Pc 2-3 waves appear as wave packets with durations in the order of 5-10 minutes. As the maximum separations of the ST-5 spacecraft are in the order of 10 minutes, the three ST-5 satellites often observe very similar wave packets, implying these wave oscillations occur in a localized region. The coordinated ground-based magnetic observations at the spacecraft footprints, however, do not see waves in the Pc 2-3 band; instead, the waves appear to be the common Pc 4-5 waves associated with field line resonances. We suggest that these unique Pc 2-3 waves seen by ST-5 are in fact the Doppler-shifted Pc 4-5 waves as a result of rapid traverse of the spacecraft across the resonant field lines azimuthally at low altitudes. The observations with the unique spacecraft dawn-disk orbits at proper altitudes and magnetic latitudes reveal the azimuthal characteristics of field-aligned resonances.

The USL NASA PC R and D development environment standards

NASA Technical Reports Server (NTRS)

Dominick, Wayne D. (Editor); Moreau, Dennis R.

1984-01-01

The development environment standards which have been established in order to control usage of the IBM PC/XT development systems and to prevent interference between projects being currently developed on the PC's are discussed. The standards address the following areas: scheduling PC resources; login/logout procedures; training; file naming conventions; hard disk organization; diskette care; backup procedures; and copying policies.

The mid-IR and near-IR interferometry of AGNs: key results and their implications

NASA Astrophysics Data System (ADS)

Kishimoto, M.

2015-09-01

Infrared interferometry has been very productive in directly probing the structure of AGNs at sub-pc scales. With tens of objects already probed in the mid-IR and near-IR, I will summarize the key results and im- plications from this direct exploration. The Keck interferometry in the near-IR and VLTI in the mid-IR shaped the luminosity dependence of the torus size and structure, while the latter also revealed an equatorial structure at several Rsub (dust sublimation radius), and a polar-elongated region at a few tens of Rsub. Notably, this polar component seems to dominate the compact mid-IR flux. This component can persuasively be attributed to a polar outflow. However, interferometry, through emissivity estimations, also indicates that it is not a UV-optically-thin cloud but participating in the obscuration of the nucleus. I will discuss how to accommodate all these facts to build a consistent picture.

Polarization beam splitter based on a photonic crystal heterostructure.

PubMed

Schonbrun, E; Wu, Q; Park, W; Yamashita, T; Summers, C J

2006-11-01

The design and characterization of a photonic crystal (PC) polarization beam splitter (PBS) that operates with an extinction ratio of greater than 15 dB for both polarizations are presented. The PBS is fabricated on a silicon-on-insulator (SOI) wafer where the input and output ports consist of 5 mum wide ridge waveguides. A large spectral shift is observed in the dispersion plots of the lowest-order even (TE-like) and odd (TM-like) modes due to the SOI confinement. Because of this shift, the TE-like mode is close to a directional gap at the top of the band, and the TM-like mode is in a low-frequency regime where the dispersion surface is almost isotropic. We show that the TE-like mode has very high reflection at the interface between the two PCs, whereas the TM-like mode exhibits a very high transmission.

Probing Membrane Order and Topography in Supported Lipid Bilayers by Combined Polarized Total Internal Reflection Fluorescence-Atomic Force Microscopy

PubMed Central

Oreopoulos, John; Yip, Christopher M.

2009-01-01

Determining the local structure, dynamics, and conformational requirements for protein-protein and protein-lipid interactions in membranes is critical to understanding biological processes ranging from signaling to the translocating and membranolytic action of antimicrobial peptides. We report here the application of a combined polarized total internal reflection fluorescence microscopy-in situ atomic force microscopy platform. This platform's ability to image membrane orientational order was demonstrated on DOPC/DSPC/cholesterol model membranes containing the fluorescent membrane probe, DiI-C20 or BODIPY-PC. Spatially resolved order parameters and fluorophore tilt angles extracted from the polarized total internal reflection fluorescence microscopy images were in good agreement with the topographical details resolved by in situ atomic force microscopy, portending use of this technique for high-resolution characterization of membrane domain structures and peptide-membrane interactions. PMID:19254557

Solvent relaxation of fluorescent labels as a new tool for the detection of polarity and rigidity changes in membranes

NASA Astrophysics Data System (ADS)

Hof, Martin; Hutterer, Rudi

1998-04-01

Since solvent relaxation (SR) exclusively depends on the physical properties of the dye environment, SR spectroscopy of defined located labels in amphiphilic assemblies accomplishes the characterisation of specific domains. The most accurate way to characterise SR is the determination of the time-dependent Stokes shift. The time course of the Stokes shift, expressed as a solvent relaxation time, gives information about both the rigidity and polarity of the dye environment. The absolute value of the Stokes shift following the excitation is correlated with the polarity of the probed region. The validity of this approach for the investigation of phospholipid bilayers is illustrated by listing the parameters influencing the SR kinetics of appropriate membrane labels: membrane curvature, percentage of phosphatidylserine (PS) in small unilamell vesicles (SUV), addition of Ca2+ ions, binding of vitamin-K dependent proteins, percentage of diether-lipids in phosphatidylcholine (PC)-vesicles, and temperature.

Occurrence and characteristics of nighttime ULF waves at low latitude: The results of a comprehensive analysis

NASA Astrophysics Data System (ADS)

Villante, Umberto; Tiberi, Pietro

2016-05-01

The occurrence and characteristics of ULF events (f ≈ 10-100 mHz) detected during the night at low latitude (L'Aquila, Italy, λ ≈ 36.3°), during quiet and moderately perturbed magnetospheric conditions, have been examined by means of a long-term analysis between 1996 and 2012. Clearly defined events (≈8000 on each component) are typically more energetic in H than in D and basically consist of penetrating upstream waves, resonances of local field lines, and Pi2 waves. The global event occurrence shows a strong asymmetry about midnight, with a much higher wave activity before dawn than after dusk: it mostly comes from the intense penetration of upstream waves through the dawn flank of the magnetopause. D events are more frequent in summer and H events more frequent in winter, suggesting a different influence of the ionospheric modification of the downgoing signals. Between f ≈ 30 and 45 mHz, the reversal of the dominant polarization across midnight reveals tailward propagation of penetrating waves. Below f ≈ 25 mHz, intermingled with continuous Pc3 and Pc4 waves, a large fraction of events exhibit Pi2 characteristics: the dominant left-handed polarization and the switch of the tilt angle of the major axis of the polarization ellipses are consistent with the pattern expected for waves related to the substorm current wedge. A relevant percentage of the power spectra shows a second enhancement above f ≈ 55 mHz, revealing resonance of local field lines also during the night.

Surface Polarity and Self-Structured Nanogrooves Collaboratively Oriented Molecular Packing for High Crystallinity toward Efficient Charge Transport.

PubMed

Ji, Deyang; Xu, Xiaomin; Jiang, Longfeng; Amirjalayer, Saeed; Jiang, Lang; Zhen, Yonggang; Zou, Ye; Yao, Yifan; Dong, Huanli; Yu, Junsheng; Fuchs, Harald; Hu, Wenping

2017-02-22

Efficient charge transport in organic semiconductors is essential for construction of high performance optoelectronic devices. Herein, for the first time, we demonstrate that poly(amic acid) (PAA), a facilely deposited and annealing-free dielectric layer, can tailor the growth of organic semiconductor films with large area and high crystallinity toward efficient charge transport and high mobility in their thin film transistors. Pentacene is used as a model system to demonstrate the concept with mobility up to 30.6 cm 2 V -1 s -1 , comparable to its high quality single crystal devices. The structure of PAA has corrugations with OH groups pointing out of the surface, and the presence of an amide bond further allows adjacent polymer strands to interact via hydrogen bonding, leading to a self-rippled surface perpendicular to the corrugation. On the other hand, the strong polar groups (-COOH/-CONH) of PAA could provide repulsive forces between PAA and pentacene, which results in the vertical orientation of pentacene on the dielectric surface. Indeed, in comparison with its imidized counterpart polyimide (PI), PAA dielectric significantly enhances the film crystallinity, drastically increases the domain size, and decreases the interface trap density, giving rise to superior device performance with high mobility. This concept can be extended to more organic semiconducting systems, e.g., 2,6-diphenylanthracene (DPA), tetracene, copper phthalocyanine (CuPc), and copper hexadecafluorophthalocyanine (F 16 CuPc), demonstrating the general applicability. The results show the importance of combining surface nanogrooves with the strong polarity in orienting the molecular arrangement for high crystallinity toward efficient charge transport in organic semiconductors.

The Structure and Emission Model of the Relativistic Jet in the Quasar 3C 279 Inferred From Radio To High-Energy Gamma-Ray Observations in 2008-2010

NASA Technical Reports Server (NTRS)

2012-01-01

We present time-resolved broad-band observations of the quasar 3C 279 obtained from multiwavelength campaigns conducted during the first two years of the Fermi Gamma-ray Space Telescope mission. While investigating the previously reported gamma-ray/optical flare accompanied by a change in optical polarization, we found that the optical emission appears delayed with respect to the gamma-ray emission by about 10 days. X-ray observations reveal a pair of 'isolated' flares separated. by approx. 90 days, with only weak gamma-ray/optical counterparts. The spectral structure measured by Spitzer reveals a synchrotron component peaking in the mid-infrared band with a sharp break at the far-infrared band during the gamma-ray flare, while the peak appears in the mm/sub-mm band in the low state. Selected spectral energy distributions are fitted with leptonic models including Comptonization of external radiation produced in a dusty torus or the broad-line region. Adopting the interpretation of the polarization swing involving propagation of the emitting region along a curved trajectory, we can explain the evolution of the broad-band spectra during the gamma-ray flaring event by a shift of its location from approx. 1 pc to approx. 4 pc from the central black hole. On the other hand, if the gamma-ray flare is generated instead at sub-pc distance from the central black hole, the far-infrared break can be explained by synchrotron self-absorption. We also model the low spectral state, dominated by the mm/sub-mm peaking synchrotron component, and suggest that the corresponding inverse-Compton component explains the steady X-ray emission.

The structure and emission model of the relativistic jet in the quasar 3C 279 inferred from radio to high-energy γ-ray observations in 2008-2010

DOE PAGES

Hayashida, M.; Madejski, G. M.; Nalewajko, K.; ...

2012-07-16

Here, we present time-resolved broadband observations of the quasar 3C 279 obtained from multi-wavelength campaigns conducted during the first two years of the Fermi Gamma-ray Space Telescope mission. And, while investigating the previously reported γ-ray/optical flare accompanied by a change in optical polarization, we found that the optical emission appears to be delayed with respect to the γ-ray emission by about 10 days. X-ray observations reveal a pair of "isolated" flares separated by ~90 days, with only weak γ-ray/optical counterparts. The spectral structure measured by Spitzer reveals a synchrotron component peaking in the mid-infrared band with a sharp break atmore » the far-infrared band during the γ-ray flare, while the peak appears in the millimeter (mm)/submillimeter (sub-mm) band in the low state. Selected spectral energy distributions are fitted with leptonic models including Comptonization of external radiation produced in a dusty torus or the broad-line region. Furthermore, by adopting the interpretation of the polarization swing involving propagation of the emitting region along a curved trajectory, we can explain the evolution of the broadband spectra during the γ-ray flaring event by a shift of its location from ~1 pc to ~4 pc from the central black hole. On the other hand, if the γ-ray flare is generated instead at sub-pc distance from the central black hole, the far-infrared break can be explained by synchrotron self-absorption. We also model the low spectral state, dominated by the mm/sub-mm peaking synchrotron component, and suggest that the corresponding inverse-Compton component explains the steady X-ray emission.« less

Increased oncogenic microRNA-18a expression in the peripheral blood of patients with prostate cancer: A potential novel non-invasive biomarker.

PubMed

Al-Kafaji, Ghada; Al-Naieb, Ziad Tariq; Bakhiet, Moiz

2016-02-01

MicroRNAs have been demonstrated to be stably detectable in peripheral blood, thus representing important sources of non-invasive biomarkers of various diseases, including cancer. Recently, microRNA-18a (miR-18a) has been revealed to be highly expressed in prostate cancer (PC) tissues, acting as an oncogenic miRNA. The present study evaluated miR-18a expression in the peripheral blood of patients with PC, patients with benign prostatic hyperplasia (BPH), and healthy individuals, to assess the feasibility of using peripheral blood miR-18a as a potential non-invasive biomarker for PC. Total RNA was extracted from peripheral whole blood samples from 24 PC patients, 24 BPH patients and 23 healthy control individuals. The expression of miR-18a was assessed by reverse transcription quantitative polymerase chain reaction. The results revealed that miR-18a expression was significantly higher in PC patients than in BPH patients and healthy controls [fold change (mean ± standard deviation), 5.5±1.4 for PC, 1.5±0.5 for BPH and 1.2±0.6 for controls; P<0.005]. Higher miR-18a expression was strongly associated with PC [odds ratio (OR), 4.602; 95% confidence interval (CI), 2.194-9.654; P=0.001], but was not significantly associated with BPH (OR, 1.2; 95% CI, 0.7-2.02; P=0.332). Despite the small number of patients, which limits the statistical power of the study, higher miR-18a expression was observed to be significantly correlated with certain clinicopathological parameters, including Gleason score >7 and pathological tumor stage 3/4 (P<0.005). A receiver operating characteristic (ROC) analysis revealed that miR-18a discriminated PC patients from BPH patients and healthy controls [area under the curve (AUC), 0.805; 95% CI, 0.704-0.906). Furthermore, use of the ROC curve to discriminate PC from BPH patients yielded an AUC of 0.878 (95% CI, 0.783-0.972). In summary, the present results indicate that miR-18a expression is significantly increased in peripheral blood of patients with PC compared with that of BPH patients and healthy individuals, and that higher miR-18a expression is associated with progression of PC. Peripheral blood oncogenic miR-18a may serve as a potential novel non-invasive biomarker for PC that also facilitates discrimination between PC and BPH.

Tracing And Control Of Engineering Requirements

NASA Technical Reports Server (NTRS)

Turner, Philip R.; Stoller, Richard L.; Neville, Ted; Boyle, Karen A.

1991-01-01

TRACER (Tracing and Control of Engineering Requirements) is data-base/word-processing software system created to document and maintain order of both requirements and descriptions associated with engineering project. Implemented on IBM PC under PC-DOS. Written with CLIPPER.

Double-Edge Sword of Sustained ROCK Activation in Prion Diseases through Neuritogenesis Defects and Prion Accumulation

PubMed Central

Alleaume-Butaux, Aurélie; Nicot, Simon; Pietri, Mathéa; Baudry, Anne; Dakowski, Caroline; Tixador, Philippe; Ardila-Osorio, Hector; Haeberlé, Anne-Marie; Bailly, Yannick; Peyrin, Jean-Michel; Launay, Jean-Marie; Kellermann, Odile; Schneider, Benoit

2015-01-01

In prion diseases, synapse dysfunction, axon retraction and loss of neuronal polarity precede neuronal death. The mechanisms driving such polarization defects, however, remain unclear. Here, we examined the contribution of RhoA-associated coiled-coil containing kinases (ROCK), key players in neuritogenesis, to prion diseases. We found that overactivation of ROCK signaling occurred in neuronal stem cells infected by pathogenic prions (PrPSc) and impaired the sprouting of neurites. In reconstructed networks of mature neurons, PrPSc-induced ROCK overactivation provoked synapse disconnection and dendrite/axon degeneration. This overactivation of ROCK also disturbed overall neurotransmitter-associated functions. Importantly, we demonstrated that beyond its impact on neuronal polarity ROCK overactivity favored the production of PrPSc through a ROCK-dependent control of 3-phosphoinositide-dependent kinase 1 (PDK1) activity. In non-infectious conditions, ROCK and PDK1 associated within a complex and ROCK phosphorylated PDK1, conferring basal activity to PDK1. In prion-infected neurons, exacerbated ROCK activity increased the pool of PDK1 molecules physically interacting with and phosphorylated by ROCK. ROCK-induced PDK1 overstimulation then canceled the neuroprotective α-cleavage of normal cellular prion protein PrPC by TACE α-secretase, which physiologically precludes PrPSc production. In prion-infected cells, inhibition of ROCK rescued neurite sprouting, preserved neuronal architecture, restored neuronal functions and reduced the amount of PrPSc. In mice challenged with prions, inhibition of ROCK also lowered brain PrPSc accumulation, reduced motor impairment and extended survival. We conclude that ROCK overactivation exerts a double detrimental effect in prion diseases by altering neuronal polarity and triggering PrPSc accumulation. Eventually ROCK emerges as therapeutic target to combat prion diseases. PMID:26241960

In-situ spectro-microscopy on organic films: Mn-Phthalocyanine on Ag(100)

NASA Astrophysics Data System (ADS)

Al-Mahboob, Abdullah; Sadowski, Jerzy T.; Vescovo, Elio

2013-03-01

Metal phthalocyanines are attracting significant attention, owing to their potential for applications in chemical sensors, solar cells and organic magnets. As the electronic properties of molecular films are determined by their crystallinity and molecular packing, the optimization of film quality is important for improving the performance of organic devices. Here, we present the results of in situ low-energy electron microscopy / photoemission electron microscopy (LEEM/PEEM) studies of incorporation-limited growth of manganese-phthalocyanine (MnPc) on Ag(100) surfaces. MnPc thin films were grown on both, bulk Ag(100) surface and thin Ag(100)/Fe(100) films, where substrate spin-polarized electronic states can be modified through tuning the thickness of the Ag film. We also discuss the electronic structure and magnetic ordering in MnPc thin films, investigated by angle- and spin-resolved photoemission spectroscopy. Research carried out at the Center for Functional Nanomaterials and National Synchrotron Light Source, Brookhaven National Laboratory, which are supported by the U.S. Dept. of Energy, Office of Basic Energy Sciences, under Contract No. DE-AC02-98CH10886.

Thermal Response Analysis of Phospholipid Bilayers Using Ellipsometric Techniques.

PubMed

González-Henríquez, Carmen M; Villegas-Opazo, Vanessa A; Sagredo-Oyarce, Dallits H; Sarabia-Vallejos, Mauricio A; Terraza, Claudio A

2017-08-18

Biomimetic planar artificial membranes have been widely studied due to their multiple applications in several research fields. Their humectation and thermal response are crucial for reaching stability; these characteristics are related to the molecular organization inside the bilayer, which is affected by the aliphatic chain length, saturations, and molecule polarity, among others. Bilayer stability becomes a fundamental factor when technological devices are developed-like biosensors-based on those systems. Thermal studies were performed for different types of phosphatidylcholine (PC) molecules: two pure PC bilayers and four binary PC mixtures. These analyses were carried out through the detection of slight changes in their optical and structural parameters via Ellipsometry and Surface Plasmon Resonance (SPR) techniques. Phospholipid bilayers were prepared by Langmuir-Blodgett technique and deposited over a hydrophilic silicon wafer. Their molecular inclination degree, mobility, and stability of the different phases were detected and analyzed through bilayer thickness changes and their optical phase-amplitude response. Results show that certain binary lipid mixtures-with differences in its aliphatic chain length-present a co-existence of two thermal responses due to non-ideal mixing.

Sorption of organic molecules on surfaces of a microporous polymer adsorbent modified with different quantities of uracil

NASA Astrophysics Data System (ADS)

Gus'kov, V. Yu.; Ganieva, A. G.; Kudasheva, F. Kh.

2016-11-01

The sorption of organic molecules on the surfaces of a number of adsorbents based on a microporous copolymer of styrene and divinylbenzene modified with different quantities of uracil is studied by means of inverse gas chromatography at infinite dilution. Samples containing 10-6, 10-5, 10-4, 10-3, 10-2, and 0.5 × 10‒1 weight parts of uracil (the pC of uracil ranges from 1.3 to 6) are studied. The contributions from different intermolecular interactions to the Helmholtz energy of sorption are calculated via the linear free energy relationship. It is found that as the concentration of uracil on the surface of the polymer adsorbent grows, the contributions from different intermolecular interactions and the conventional polarity of the surface have a bend at pC = 3, due probably to the formation of a supramolecular structure of uracil. Based on the obtained results, it is concluded that the formation of the supramolecular structure of uracil on the surface of the polymer adsorbent starts when pC < 3.

Network Analysis Identifies Proinflammatory Plasma Cell Polarization for Secretion of ISG15 in Human Autoimmunity

PubMed Central

Care, Matthew A.; Stephenson, Sophie J.; Barnes, Nicholas A.; Fan, Im; Zougman, Alexandre; El-Sherbiny, Yasser M.; Vital, Edward M.; Westhead, David R.; Tooze, Reuben M.

2016-01-01

Plasma cells (PCs) as effectors of humoral immunity produce Igs to match pathogenic insult. Emerging data suggest more diverse roles exist for PCs as regulators of immune and inflammatory responses via secretion of factors other than Igs. The extent to which such responses are preprogrammed in B-lineage cells or can be induced in PCs by the microenvironment is unknown. In this study, we dissect the impact of IFNs on the regulatory networks of human PCs. We show that core PC programs are unaffected, whereas PCs respond to IFNs with distinctive transcriptional responses. The IFN-stimulated gene 15 (ISG15) system emerges as a major transcriptional output induced in a sustained fashion by IFN-α in PCs and linked both to intracellular conjugation and ISG15 secretion. This leads to the identification of ISG15-secreting plasmablasts/PCs in patients with active systemic lupus erythematosus. Thus, ISG15-secreting PCs represent a distinct proinflammatory PC subset providing an Ig-independent mechanism of PC action in human autoimmunity. PMID:27357150

Biomimicry 1: PC.

PubMed

Cumberland, D C; Gunn, J; Malik, N; Holt, C M

1998-01-01

The surface properties of stents can be modified by coating them, for example with a polymer. Phosphorylcoline (PC) is the major component of the outer layer of the cell membrane. The haemo- and biocompatibility of a PC-containing polymer is thus based on biomimicry, and has been confirmed by several experiments showing much reduced thrombogenicity of PC-coated surfaces, and porcine coronary artery implants showing no sign of adverse effect. Clinical experience with the PC-coated BiodivYsio appears favourable. The PC coating can be tailored for take up and controlled elution of various drugs for stent-based local delivery, a property which is being actively explored.

Dietary Components Affect the Plasma and Tissue Levels of Lutein in Aged Rats with Lutein Deficiency--A Repeated Gavage and Dietary Study.

PubMed

Sheshappa, Mamatha Bangera; Ranganathan, Arunkumar; Bhatiwada, Nidhi; Talahalli, Ramprasad Ravichandra; Vallikannan, Baskaran

2015-10-01

The aim of this study was to find out the influence of selected dietary components on plasma and tissue response of repeated micellar and dietary lutein in aged rats with lutein deficiency. In repeated (16 d) gavage study, micellar lutein was co-ingested with either phosphatidylcholine (PC), lyso-phosphatidylcholine (lysoPC), β-carotene, dietary fiber or vegetable fat (3% soybean oil). In dietary study, rats were fed (4 wk) semi-synthetic diet either with lutein + PC, lutein + dietary fiber or B. alba (lutein source) + PC. The post-prandial plasma and tissue response of lutein was measured by HPLC. Results showed that micellar fat, PC and lysoPC significantly (P ≤ 0.05) increased the lutein levels in plasma (31.1%, 26.8%, and 34.9%), liver (27.4%, 29.5%, and 8.6%), and eyes (63.5%, 90.2%, and 86%) compared to the control group (group gavaged micelles with no dietary components studied). Similarly, dietary study showed an enhanced plasma, liver, and eye lutein levels by 44.8%, 24.1%, and 42.0% (lutein + PC group) and 51.7%, 39.8%, and 31.7% (B.alba + PC group), respectively compared to control. The activity of antioxidant enzymes in plasma and liver of both the studies were also affected compared to control. Result reveals, that PC enhance the intestinal absorption of both micellar and dietary lutein which is either in free or bound form with food matrices in aged rats with lutein deficiency. Hence, PC at a concentration used in this study can be considered to improve the lutein bioavailability in lutein deficiency. Lutein and zeaxanthin are macular pigments acquired mostly from greens, that play an significant role in protecting vision from Age related macular degeneration (AMD). However, their biological availability is poor and affected by dietary components. This study demonstrates the positive influence of dietary PC and lyso PC in improving intestinal uptake of lutein. Our previous and present finding shows there is a possibility of developing functional/supplemental foods with PC and lyso PC targeted to elderly populace thus minimizing or delaying the vision complication associated like AMD. © 2015 Institute of Food Technologists®

The Fossil Nuclear Outflow in the Central 30 pc of the Galactic Center

NASA Astrophysics Data System (ADS)

Hsieh, Pei-Ying; Ho, Paul T. P.; Hwang, Chorng-Yuan; Shimajiri, Yoshito; Matsushita, Satoki; Koch, Patrick M.; Iono, Daisuke

2016-11-01

We report a new 1 pc (30″) resolution CS(J=2-1) line map of the central 30 pc of the Galactic center (GC), made with the Nobeyama 45 m telescope. We revisit our previous study of an extraplanar feature called the polar arc (PA), which is a molecular cloud located above SgrA*, with a velocity gradient perpendicular to the galactic plane. We find that the PA can be traced back to the galactic disk. This provides clues to the launching point of the PA, roughly 6 × 106 years ago. Implications of the dynamical timescale of the PA might be related to the Galactic center lobe at parsec scale. Our results suggest that, in the central 30 pc of the GC, the feedback from past explosions could alter the orbital path of molecular gas down to the central tenth of a parsec. In the follow-up work of our new CS(J=2-1) map, we also find that, near systemic velocity, the molecular gas shows an extraplanar hourglass-shaped feature (HG-feature) with a size of ˜13 pc. The latitude-velocity diagrams show that the eastern edge of the HG-feature is associated with an expanding bubble B1, ˜7 pc away from SgrA*. The dynamical timescale of this bubble is ˜3 × 105 years. This bubble is interacting with the 50 km s-1 cloud. Part of the molecular gas from the 50 km s-1 cloud was swept away by the bubble to b=-0\\buildrel{\\circ}\\over{.} 2. The western edge of the HG-feature seems to be molecular gas entrained from the 20 km s-1 cloud toward the north of the galactic disk. Our results suggest a fossil explosion in the central 30 pc of the GC, a few 105 years ago.

Acute administration of vitamin C abrogates protection from ischemic preconditioning in rabbits.

PubMed

Tsovolas, Konstantinos; Iliodromitis, Efstathios K; Andreadou, Ioanna; Zoga, Anastasia; Demopoulou, Maritina; Iliodromitis, Konstantinos E; Manolaki, Theodora; Markantonis, Sophia L; Kremastinos, Dimitrios Th

2008-04-01

Vitamin C is considered to be an antioxidant agent that is broadly used. Free radicals are involved in the protective mechanism of preconditioning (PC), but some antioxidant compounds abolish this benefit. The aim of the present study was to evaluate the effect of vitamin C on the protective effect of PC with respect to infarct size and oxidative stress in anesthetized rabbits. Male rabbits were randomly divided into six groups and subjected to 30 min of myocardial ischemia and 3h of reperfusion with the following interventions per group: (1) Control (no intervention), (2) Vit C 150 group (i.v. vitamin C at a total dose of 150 mg/kg for 75 min, starting 40 min before the onset of long ischemia and lasting up to the 5th min of reperfusion), (3) Vit C 300 group (i.v. vitamin C at a total dose of 300 mg/kg as previously described), (4) PC group (two cycles of 5 min ischemia and 10 min reperfusion), (5) combined PC-Vit C 150 group and (6) combined PC-Vit C 300 group. Blood samples were taken at different time points for malondialdehyde (MDA) assessment as a lipid peroxidation marker and for superoxide dismutase (SOD) activity. At the end of the experiment the infarct size was determined. Vitamin C, at both doses, did not reduce the infarct size (35.5+/-4.1%, 38.3+/-7.0% vs. 44.9+/-3.3% in the control group) and diminished the protection afforded by PC (32.0+/-2.7%, 43.8+/-3.3% vs. 15.7+/-2.9% in the PC group, P<0.05). At reperfusion there was an elevation of circulating MDA levels in the control and PC groups while in both vitamin C groups the levels were decreased. SOD activity was enhanced in the PC group compared to the controls; vitamin C did not change SOD activity during ischemia-reperfusion. Vitamin C abrogates the beneficial effect of ischemic PC on infarct size and elicits antioxidant properties during ischemia-reperfusion.

Search for liquids electrospraying the smallest possible nanodrops in vacuo

NASA Astrophysics Data System (ADS)

Alonso-Matilla, R.; Fernández-García, J.; Congdon, H.; Fernández de la Mora, J.

2014-12-01

Prior work with electrosprays in vacuum of mixtures of ionic liquids (ILs) and the moderately high boiling point (Tb) solvents formamide (FM) and propylene carbonate (PC) (Tb of 210 and 241 °C) has shown that the charged drops produced have reasonably narrow charge/mass distributions, controllable over a wide mass/charge range. This enables their use as propellants in electrical propulsion with specific impulse Isp varying from a few hundred to a few thousand seconds (10 kV beam energy) and with excellent propulsion efficiency. However, some limitations are imposed by the finite room temperature volatility of FM and PC. Here, we seek improved performance from propellants based on the polar but viscous solvent Sulfolane (SF; ɛ = 43.2, μ = 10.3 cP) and the low viscosity but less polar solvent tributyl phosphate (TBP; ɛ = 8.9, μ = 3.4 cP), both with Tb > 280 °C. Neither TBP nor its low viscosity mixtures with SF achieve the electrical conductivities needed to yield high Isp. Most ILs used in SF/IL mixtures tested were based on the 1-ethyl-3-methylimidazolium (EMI) or 1,3-dimethylimidazolium (DMI) cations, including EMI-BF4, EMI-N(CN)2, and DMI-N(CN)2. These combinations reach high conductivities, some approaching 3 S/m, but have limited propulsive performance because evaporation of ions directly from the electrified meniscus produces undesirable mixed beams of drops and ions. Exceptional characteristics are found in mixtures of SF with ethylammonium nitrate (EAN), where the small EA+ cation is strongly bound to the solvent, greatly delaying ion evaporation from the meniscus. Evidence on the formation of nano-jets with diameters as small as 1 nm is seen. Although unprecedented, this finding agrees with what would be expected if ion evaporation were suppressed. SF/EAN mixtures thus provide the best available sources to produce the smallest possible nanodrops, minimally polluted by ions.

Integration of targeted metabolomics and transcriptomics identifies deregulation of phosphatidylcholine metabolism in Huntington's disease peripheral blood samples.

PubMed

Mastrokolias, Anastasios; Pool, Rene; Mina, Eleni; Hettne, Kristina M; van Duijn, Erik; van der Mast, Roos C; van Ommen, GertJan; 't Hoen, Peter A C; Prehn, Cornelia; Adamski, Jerzy; van Roon-Mom, Willeke

Metabolic changes have been frequently associated with Huntington's disease (HD). At the same time peripheral blood represents a minimally invasive sampling avenue with little distress to Huntington's disease patients especially when brain or other tissue samples are difficult to collect. We investigated the levels of 163 metabolites in HD patient and control serum samples in order to identify disease related changes. Additionally, we integrated the metabolomics data with our previously published next generation sequencing-based gene expression data from the same patients in order to interconnect the metabolomics changes with transcriptional alterations. This analysis was performed using targeted metabolomics and flow injection electrospray ionization tandem mass spectrometry in 133 serum samples from 97 Huntington's disease patients (29 pre-symptomatic and 68 symptomatic) and 36 controls. By comparing HD mutation carriers with controls we identified 3 metabolites significantly changed in HD (serine and threonine and one phosphatidylcholine-PC ae C36:0) and an additional 8 phosphatidylcholines (PC aa C38:6, PC aa C36:0, PC ae C38:0, PC aa C38:0, PC ae C38:6, PC ae C42:0, PC aa C36:5 and PC ae C36:0) that exhibited a significant association with disease severity. Using workflow based exploitation of pathway databases and by integrating our metabolomics data with our gene expression data from the same patients we identified 4 deregulated phosphatidylcholine metabolism related genes ( ALDH1B1 , MBOAT1 , MTRR and PLB1 ) that showed significant association with the changes in metabolite concentrations. Our results support the notion that phosphatidylcholine metabolism is deregulated in HD blood and that these metabolite alterations are associated with specific gene expression changes.

The Neuronal Ischemic Tolerance Is Conditioned by the Tp53 Arg72Pro Polymorphism.

PubMed

Ramos-Araque, Maria E; Rodriguez, Cristina; Vecino, Rebeca; Cortijo Garcia, Elisa; de Lera Alfonso, Mercedes; Sanchez Barba, Mercedes; Colàs-Campàs, Laura; Purroy, Francisco; Arenillas, Juan F; Almeida, Angeles; Delgado-Esteban, Maria

2018-04-23

Cerebral preconditioning (PC) confers endogenous brain protection after stroke. Ischemic stroke patients with a prior transient ischemic attack (TIA) may potentially be in a preconditioned state. Although PC has been associated with the activation of pro-survival signals, the mechanism by which preconditioning confers neuroprotection is not yet fully clarified. Recently, we have described that PC-mediated neuroprotection against ischemic insult is promoted by p53 destabilization, which is mediated by its main regulator MDM2. Moreover, we have previously described that the human Tp53 Arg72Pro single nucleotide polymorphism (SNP) controls susceptibility to ischemia-induced neuronal apoptosis and governs the functional outcome of patients after stroke. Here, we studied the contribution of the human Tp53 Arg72Pro SNP on PC-induced neuroprotection after ischemia. Our results showed that cortical neurons expressing the Pro72-p53 variant exhibited higher PC-mediated neuroprotection as compared with Arg72-p53 neurons. PC prevented ischemia-induced nuclear and cytosolic p53 stabilization in Pro72-p53 neurons. However, PC failed to prevent mitochondrial p53 stabilization, which occurs in Arg72-p53 neurons after ischemia. Furthermore, PC promoted neuroprotection against ischemia by controlling the p53/active caspase-3 pathway in Pro72-p53, but not in Arg72-p53 neurons. Finally, we found that good prognosis associated to TIA within 1 month prior to ischemic stroke was restricted to patients harboring the Pro72 allele. Our findings demonstrate that the Tp53 Arg72Pro SNP controls PC-promoted neuroprotection against a subsequent ischemic insult by modulating mitochondrial p53 stabilization and then modulates TIA-induced ischemic tolerance.

Stuxnet Facilitates the Degradation of Polycomb Protein during Development.

PubMed

Du, Juan; Zhang, Junzheng; He, Tao; Li, Yajuan; Su, Ying; Tie, Feng; Liu, Min; Harte, Peter J; Zhu, Alan Jian

2016-06-20

Polycomb-group (PcG) proteins function to ensure correct deployment of developmental programs by epigenetically repressing target gene expression. Despite the importance, few studies have been focused on the regulation of PcG activity itself. Here, we report a Drosophila gene, stuxnet (stx), that controls Pc protein stability. We find that heightened stx activity leads to homeotic transformation, reduced Pc activity, and de-repression of PcG targets. Conversely, stx mutants, which can be rescued by decreased Pc expression, display developmental defects resembling hyperactivation of Pc. Our biochemical analyses provide a mechanistic basis for the interaction between stx and Pc; Stx facilitates Pc degradation in the proteasome, independent of ubiquitin modification. Furthermore, this mode of regulation is conserved in vertebrates. Mouse stx promotes degradation of Cbx4, an orthologous Pc protein, in vertebrate cells and induces homeotic transformation in Drosophila. Our results highlight an evolutionarily conserved mechanism of regulated protein degradation on PcG homeostasis and epigenetic activity. Copyright © 2016 Elsevier Inc. All rights reserved.

Low back pain and postural control, effects of task difficulty on centre of pressure and spinal kinematics.

PubMed

Schelldorfer, Sarah; Ernst, Markus Josef; Rast, Fabian Marcel; Bauer, Christoph Michael; Meichtry, André; Kool, Jan

2015-01-01

Association of low back pain and standing postural control (PC) deficits are reported inconsistently. Demands on PC adaptation strategies are increased by restraining the input of visual or somatosensory senses. The objectives of the current study are, to investigate whether PC adaptations of the spine, hip and the centre of pressure (COP) differ between patients reporting non-specific low back pain (NSLBP) and asymptomatic controls. The PC adaption strategies of the thoracic and lumbar spine, the hip and the COP were measured in fifty-seven NSLBP patients and 22 asymptomatic controls. We tested three "feet together" conditions with increasing demands on PC strategies, using inertial measurement units (IMUs) on the spine and a Wii balance board for centre of pressure (COP) parameters. The differences between NSLBP patients and controls were most apparent when the participants were blindfolded, but remaining on a firm surface. While NSLBP patients had larger thoracic and lumbar spine mean absolute deviations of position (MADpos) in the frontal plane, the same parameters decreased in control subjects (relative change (RC): 0.23, 95% confidence interval: 0.03 to 0.45 and 0.03 to 0.48). The Mean absolute deviation of velocity (MADvel) of the thoracic spine in the frontal plane showed a similar and significant effect (RC: 0.12 95% CI: 0.01 to 0.25). Gender, age and pain during the measurements affected some parameters significantly. PC adaptions differ between NSLBP patients and asymptomatic controls. The differences are most apparent for the thoracic and lumbar parameters of MADpos, in the frontal plane and while the visual condition was removed. Copyright © 2014 Elsevier B.V. All rights reserved.

Tentative Identification of Interstellar Dust in the Magnetic Wall of the Heliosphere

NASA Astrophysics Data System (ADS)

Frisch, P. C.

2006-06-01

Data showing that light from nearby stars, <40 pc, is weakly polarized are consistent with the capture and alignment of dust grains in the magnetic wall of the heliosphere. These data, from Tinbergen (1982) and Piirola (1977), were acquired during the solar minimum of the mid-1970's when the magnetic wall was expected to form at negative ecliptic latitudes because the solar magnetic polarity was north-pole-positive. The polarization is seen primarily at negative ecliptic latitudes, consistent with the expected magnetic wall position. The interstellar magnetic field direction at the Sun is derived from these data. The small dust grains most likely to cause the polarization are also the grains excluded from the heliosphere by small gyroradii, <100 AU. The direction of maximum polarization is offset by ˜ 20 --40 deg. from the inflow direction of the large grains that are gravitationally focused in the heliosphere tail. Interstellar dust grains in and near the heliosphere form a potential contaminant of the cosmic microwave background signal, which should then be identifiable because the spatial behavior of these grains depends on the phase of the 22 year solar magnetic activity cycle. The author would like to thank NASA for supporting her research.

Application of Optical Forces in Microphotonic Systems

DTIC Science & Technology

2013-05-01

Experiments are carried out to optically characterize the high-Q guided resonance modes with slot confinement. The evolution of the measured wavelengths...the guided resonant device. Two cross polarizers (PC) are applied before and after the device to cancel out Fabry-Perot noise. TL: tunable laser; MO...carried out to optically characterize the high-Q guided resonance modes with slot confinement. The evolution of the measured wavelengths and quality

High-performance polymer/layered silicate nanocomposites

NASA Astrophysics Data System (ADS)

Heidecker, Matthew J.

High-performance layered-silicate nanocomposites of Polycarbonate (PC), poly(ethylene terephthalate) (PET), and their blends were produced via conventional melt-blending techniques. The focus of this thesis was on the fundamentals of dispersion, control of thermal stability, maintenance of melt-blending processing conditions, and on optimization of the composites' mechanical properties via the design of controlled and thermodynamically favorable nano-filler dispersions within the polymer matrices. PET and PC require high temperatures for melt-processing, rendering impractical the use of conventional/commercial organically-modified layered-silicates, since the thermal degradation temperatures of their ammonium surfactants lies below the typical processing temperatures. Thus, different surfactant chemistries must be employed in order to develop melt-processable nanocomposites, also accounting for polymer matrix degradation due to water (PET) or amine compounds (PC). Novel high thermal-stability surfactants were developed and employed in montmorillonite nanocomposites of PET, PC, and PC/PET blends, and were compared to the respective nanocomposites based on conventional quaternary-ammonium modified montmorillonites. Favorable dispersion was achieved in all cases, however, the overall material behavior -- i.e., the combination of crystallization, mechanical properties, and thermal degradation -- was better for the nanocomposites based on the thermally-stable surfactant fillers. Studies were also done to trace, and ultimately limit, the matrix degradation of Polycarbonate/montmorillonite nanocomposites, through varying the montmorillonite surfactant chemistry, processing conditions, and processing additives. Molecular weight degradation was, maybe surprisingly, better controlled in the conventional quaternary ammonium based nanocomposites -- even though the thermal stability of the organically modified montmorillonites was in most cases the lowest. Dependence of the resultant nanocomposites' mechanical properties on the preferential alignment of the montmorillonite nano-platelet was also evaluated. Highly aligned filler platelets did not result in an additional enhancement in mechanical properties. PC/PET blends and their respective PC/PET/montmorillonite nanocomposites were synthesized and compared. The dispersion of the organically modified nano-fillers in the PC/PET blends was controlled via thermodynamic considerations, realized through proper surfactant choice: Nanocomposites in which the layered silicate was preferentially sequestered in the PET phase were designed and synthesized. This preferential dispersion of the nano-filler in the PET phase of the PC/PET blend was insensitive to processing conditions, including approaches employing a master-batch (filler concentrate); regardless of the master-batch matrix, both PC and PET were employed, thermodynamics drove the layered silicate to preferentially migrate to the PET phase of the PC/PET blend. In a second approach, the development of a nanocomposite with controlled PC/PET compatibilization near the montmorillonite platelets, in absence of appreciable transesterification reactions, led to the formation of very high performance nanocomposites. These latter systems, point to an exciting new avenue of future considerations for nanocomposite blends with selective nano-filler dispersions, where performance can be tailored via the controlled preferential dispersion of nano-fillers in one phase, or by filler-induced polymer compatibilization.

Evaluation of the Missouri WIC (Special Supplemental Nutrition Program for Women, Infants, and Children) breast-feeding peer counselling programme.

PubMed

Yun, Shumei; Liu, Qian; Mertzlufft, Kathy; Kruse, Catherine; White, Maggie; Fuller, Phyllis; Zhu, Bao-Ping

2010-02-01

To evaluate the effectiveness of the peer counselling (PC) programme on breast-feeding initiation among participants in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) in Missouri, and to identify factors that facilitate breast-feeding initiation. We used the data from the 2006 Missouri Pregnancy Nutrition Surveillance System, Missouri Live Birth Records and the Missouri WIC programme to compare breast-feeding initiation rates between PC and non-PC agencies. We used multilevel logistic regression, with individual participants being nested within agencies, to control for individual- and agency-level characteristics. The breast-feeding initiation rate in PC agencies was significantly higher than in non-PC agencies among prenatal participants, but the difference was not significant among postpartum participants. After controlling for maternal sociodemographic characteristics, compared with prenatal cases in non-PC agencies, prenatal cases in PC agencies were more likely to initiate breast-feeding (OR = 1.21; 95 % CI 1.03, 1.43), whereas postpartum cases were less likely to initiate breast-feeding. Among prenatal participants in PC agencies, longer duration of prenatal WIC enrolment was associated with a higher rate of breast-feeding initiation. After adjusting for maternal sociodemographic characteristics and other agency-level characteristics, participants of PC agencies with an international board-certified lactation consultant were more likely to initiate breast-feeding than participants of PC agencies without such a consultant (OR = 1.21; 95 % CI 1.01, 1.45). Prenatal participation in the WIC breast-feeding PC programme (especially participation early during pregnancy) was associated with an increased rate of breast-feeding initiation in Missouri.

Mass Spectrometric Analyses of Phosphatidylcholines in Alkali-Exposed Corneal Tissue

PubMed Central

Crane, Ashley M.; Hua, Hong-Uyen; Coggin, Andrew D.; Gugiu, Bogdan G.; Lam, Byron L.; Bhattacharya, Sanjoy K.

2012-01-01

Purpose. The aims were to determine whether exposure to sodium hydroxide results in predictable changes in phosphatidylcholine (PC) in corneal tissue and if PC profile changes correlate to exposure duration. PCs are major components of the cell membrane lipid bilayer and are often involved in biological processes such as signaling. Methods. Enucleated porcine (n = 140) and cadaver human eyes (n = 20) were exposed to water (control) and 11 M NaOH. The corneas were excised and lipids were extracted using the Bligh and Dyer method with suitable modifications. Class-specific lipid identification was carried out using a ratiometric lipid standard on a TSQ Quantum Access Max mass spectrometer. Protein amounts were determined using Bradford assays. Results. Control and alkali-treated corneas showed reproducible PC spectra for both porcine and human corneas. Over 200 PCs were identified for human and porcine control and each experimental time point. Several PC species (m/z values) consequent upon alkali exposure could not be ascribed to a recorded PC species. Control and treated groups showed 41 and 29 common species among them for porcine and human corneas, respectively. The unique PC species peaked at 12 minutes and at 30 minutes for human and porcine corneas followed by a decline consistent with an interplay of alkali penetration and hydrolyses at various time points. Conclusions. Alkali exposure dramatically changes the PC profile of cornea. Our data are consistent with penetration and hydrolysis as stochastic contributors to changes in PCs due to exposure to alkali for a finite duration and amount. PMID:22956606

Cellular prion protein controls stem cell-like properties of human glioblastoma tumor-initiating cells.

PubMed

Corsaro, Alessandro; Bajetto, Adriana; Thellung, Stefano; Begani, Giulia; Villa, Valentina; Nizzari, Mario; Pattarozzi, Alessandra; Solari, Agnese; Gatti, Monica; Pagano, Aldo; Würth, Roberto; Daga, Antonio; Barbieri, Federica; Florio, Tullio

2016-06-21

Prion protein (PrPC) is a cell surface glycoprotein whose misfolding is responsible for prion diseases. Although its physiological role is not completely defined, several lines of evidence propose that PrPC is involved in self-renewal, pluripotency gene expression, proliferation and differentiation of neural stem cells. Moreover, PrPC regulates different biological functions in human tumors, including glioblastoma (GBM). We analyzed the role of PrPC in GBM cell pathogenicity focusing on tumor-initiating cells (TICs, or cancer stem cells, CSCs), the subpopulation responsible for development, progression and recurrence of most malignancies. Analyzing four GBM CSC-enriched cultures, we show that PrPC expression is directly correlated with the proliferation rate of the cells. To better define its role in CSC biology, we knocked-down PrPC expression in two of these GBM-derived CSC cultures by specific lentiviral-delivered shRNAs. We provide evidence that CSC proliferation rate, spherogenesis and in vivo tumorigenicity are significantly inhibited in PrPC down-regulated cells. Moreover, PrPC down-regulation caused loss of expression of the stemness and self-renewal markers (NANOG, Sox2) and the activation of differentiation pathways (i.e. increased GFAP expression). Our results suggest that PrPC controls the stemness properties of human GBM CSCs and that its down-regulation induces the acquisition of a more differentiated and less oncogenic phenotype.

Cellular prion protein controls stem cell-like properties of human glioblastoma tumor-initiating cells

PubMed Central

Corsaro, Alessandro; Bajetto, Adriana; Thellung, Stefano; Begani, Giulia; Villa, Valentina; Nizzari, Mario; Pattarozzi, Alessandra; Solari, Agnese; Gatti, Monica; Pagano, Aldo; Würth, Roberto; Daga, Antonio; Barbieri, Federica; Florio, Tullio

2016-01-01

Prion protein (PrPC) is a cell surface glycoprotein whose misfolding is responsible for prion diseases. Although its physiological role is not completely defined, several lines of evidence propose that PrPC is involved in self-renewal, pluripotency gene expression, proliferation and differentiation of neural stem cells. Moreover, PrPC regulates different biological functions in human tumors, including glioblastoma (GBM). We analyzed the role of PrPC in GBM cell pathogenicity focusing on tumor-initiating cells (TICs, or cancer stem cells, CSCs), the subpopulation responsible for development, progression and recurrence of most malignancies. Analyzing four GBM CSC-enriched cultures, we show that PrPC expression is directly correlated with the proliferation rate of the cells. To better define its role in CSC biology, we knocked-down PrPC expression in two of these GBM-derived CSC cultures by specific lentiviral-delivered shRNAs. We provide evidence that CSC proliferation rate, spherogenesis and in vivo tumorigenicity are significantly inhibited in PrPC down-regulated cells. Moreover, PrPC down-regulation caused loss of expression of the stemness and self-renewal markers (NANOG, Sox2) and the activation of differentiation pathways (i.e. increased GFAP expression). Our results suggest that PrPC controls the stemness properties of human GBM CSCs and that its down-regulation induces the acquisition of a more differentiated and less oncogenic phenotype. PMID:27229535

Minia, Egypt: Principal Component Analysis

PubMed

Abdelrehim, Marwa G; Mahfouz, Eman M; Ewis, Ashraf A; Seedhom, Amany E; Afifi, Hassan M; Shebl, Fatma M

2018-02-26

Background: Pancreatic cancer (PC) is a serious and rapidly progressing malignancy. Identifying risk factors including dietary elements is important to develop preventive strategies. This study focused on possible links between diet and PC. Methods: We conducted a case-control study including all PC patients diagnosed at Minia Cancer Center and controls from general population from June 2014 to December 2015. Dietary data were collected directly through personal interviews. Principal component analysis (PCA) was performed to identify dietary groups. The data were analyzed using crude odds ratios (ORs) and multivariable logistic regression with adjusted ORs and 95% confidence intervals (CIs). Results: A total of 75 cases and 149 controls were included in the study. PCA identified six dietary groups, labeled as cereals and grains, vegetables, proteins, dairy products, fruits, and sugars. Bivariate analysis showed that consumption of vegetables, fruits, sugars, and total energy intake were associated with change in PC risk. In multivariable-adjusted models comparing highest versus lowest levels of intake, we observed significant lower odds of PC in association with vegetable intake (OR 0.24; 95% CI, 0.07-0.85, P=0.012) and a higher likelihood with the total energy intake (OR 9.88; 95% CI, 2.56-38.09, P<0.0001). There was also a suggested link between high fruit consumption and reduced odds of PC. Conclusions: The study supports the association between dietary factors and the odds of PC development in Egypt. It was found that higher energy intake is associated with an increase in likelihood of PC, while increased vegetable consumption is associated with a lower odds ratio. Creative Commons Attribution License

Zinc phthalocyanine-loaded PLGA biodegradable nanoparticles for photodynamic therapy in tumor-bearing mice.

PubMed

Fadel, Maha; Kassab, Kawser; Fadeel, Doa Abdel

2010-03-01

Nanoparticles formulated from the biodegradable copolymer poly(lactic-coglycolic acid) (PLGA) were investigated as a drug delivery system to enhance tissue uptake, permeation, and targeting of zinc(II) phthalocyanine (ZnPc) for photodynamic therapy. Three ZnPc nanoparticle formulations were prepared using a solvent emulsion evaporation method and the influence of sonication time on nanoparticle shape, encapsulation and size distribution, in vitro release, and in vivo photodynamic efficiency in tumor-bearing mice were studied. Sonication time did not affect the process yield or encapsulation efficiency, but did affect significantly the particle size. Sonication for 20 min reduced the mean particle size to 374.3 nm and the in vitro release studies demonstrated a controlled release profile of ZnPc. Tumor-bearing mice injected with ZnPc nanoparticles exhibited significantly smaller mean tumor volume, increased tumor growth delay and longer survival compared with the control group and the group injected with free ZnPc during the time course of the experiment. Histopathological examination of tumor from animals treated with PLGA ZnPc showed regression of tumor cells, in contrast to those obtained from animals treated with free ZnPc. The results indicate that ZnPc encapsulated in PLGA nanoparticles is a successful delivery system for improving photodynamic activity in the target tissue.

Validation of N-glycan markers that improve the performance of CA19-9 in pancreatic cancer.

PubMed

Zhao, Yun-Peng; Zhou, Ping-Ting; Ji, Wei-Ping; Wang, Hao; Fang, Meng; Wang, Meng-Meng; Yin, Yue-Peng; Jin, Gang; Gao, Chun-Fang

2017-02-01

Pancreatic cancer (PC) has a high mortality rate because it is usually diagnosed late. Glycosylation of proteins is known to change in tumor cells during the development of PC. The objectives of this study were to identify and validate the diagnostic value of novel biomarkers based on N-glycomic profiling for PC. In total, 217 individuals including subjects with PC, pancreatitis, and healthy controls were divided randomly into a training group (n = 164) and validation groups (n = 53). Serum N-glycomic profiling was analyzed by DSA-FACE. The diagnostic model was constructed based on N-glycan markers with logistic stepwise regression. The diagnostic performance of the model was assessed further in validation cohort. The level of total core fucose residues was increased significantly in PC. Two diagnostic models designated GlycoPCtest and PCmodel (combining GlycoPCtest and CA19-9) were constructed to differentiate PC from normal. The area under the receiver operating characteristic curve (AUC) of PCmodel was higher than that of CA19-9 (0.925 vs. 0.878). The diagnostic models based on N-glycans are new, valuable, noninvasive alternatives for identifying PC. The diagnostic efficacy is improved by combined GlycoPCtest and CA19-9 for the discrimination of patients with PC from healthy controls.

PC/AT-based architecture for shared telerobotic control

NASA Astrophysics Data System (ADS)

Schinstock, Dale E.; Faddis, Terry N.; Barr, Bill G.

1993-03-01

A telerobotic control system must include teleoperational, shared, and autonomous modes of control in order to provide a robot platform for incorporating the rapid advances that are occurring in telerobotics and associated technologies. These modes along with the ability to modify the control algorithms are especially beneficial for telerobotic control systems used for research purposes. The paper describes an application of the PC/AT platform to the control system of a telerobotic test cell. The paper provides a discussion of the suitability of the PC/AT as a platform for a telerobotic control system. The discussion is based on the many factors affecting the choice of a computer platform for a real time control system. The factors include I/O capabilities, simplicity, popularity, computational performance, and communication with external systems. The paper also includes a description of the actuation, measurement, and sensor hardware of both the master manipulator and the slave robot. It also includes a description of the PC-Bus interface cards. These cards were developed by the researchers in the KAT Laboratory, specifically for interfacing to the master manipulator and slave robot. Finally, a few different versions of the low level telerobotic control software are presented. This software incorporates shared control by supervisory systems and the human operator and traded control between supervisory systems and the human operator.

The Sub-Polar Gyre Index - a community data set for application in fisheries and environment research

NASA Astrophysics Data System (ADS)

Berx, Barbara; Payne, Mark R.

2017-04-01

Scientific interest in the sub-polar gyre of the North Atlantic Ocean has increased in recent years. The sub-polar gyre has contracted and weakened, and changes in circulation pathways have been linked to changes in marine ecosystem productivity. To aid fisheries and environmental scientists, we present here a time series of the Sub-Polar Gyre Index (SPG-I) based on monthly mean maps of sea surface height. The established definition of the SPG-I is applied, and the first EOF (empirical orthogonal function) and PC (principal component) are presented. Sensitivity to the spatial domain and time series length are explored but found not to be important factors in terms of the SPG-I's interpretation. Our time series compares well with indices presented previously. The SPG-I time series is freely available online (http://dx.doi.org/10.7489/1806-1), and we invite the community to access, apply, and publish studies using this index time series.

75 FR 17402 - Public Utility District No. 1 of Snohomish County, WA; Notice of Preliminary Permit Application...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-06

... and Control building (PC&C); (6) a PC&C building; (7) an approximately 460-foot-long, 3.3-kilovolt (kV) power cable bringing power from the PC&C building to the 12-kV Puget Sound Energy grid; and (8...

Cellular Migration and Invasion Uncoupled: Increased Migration Is Not an Inexorable Consequence of Epithelial-to-Mesenchymal Transition

PubMed Central

Schaeffer, Daneen; Somarelli, Jason A.; Hanna, Gabi; Palmer, Gregory M.

2014-01-01

Metastatic dissemination requires carcinoma cells to detach from the primary tumor and invade through the basement membrane. To acquire these characteristics, epithelial tumor cells undergo epithelial-to-mesenchymal transitions (EMT), whereby cells lose polarity and E-cadherin-mediated cell-cell adhesion. Post-EMT cells have also been shown, or assumed, to be more migratory; however, there have been contradictory reports on an immortalized human mammary epithelial cell line (HMLE) that underwent EMT. In the context of carcinoma-associated EMT, it is not yet clear whether the change in migration and invasion must be positively correlated during EMT or whether enhanced migration is a necessary consequence of having undergone EMT. Here, we report that pre-EMT rat prostate cancer (PC) and HMLE cells are more migratory than their post-EMT counterparts. To determine a mechanism for increased epithelial cell migration, gene expression analysis was performed and revealed an increase in epidermal growth factor receptor (EGFR) expression in pre-EMT cells. Indeed, inhibition of EGFR in PC epithelial cells slowed migration. Importantly, while post-EMT PC and HMLE cell lines are less migratory, both remain invasive in vitro and, for PC cells, in vivo. Our study demonstrates that enhanced migration is not a phenotypic requirement of EMT, and migration and invasion can be uncoupled during carcinoma-associated EMT. PMID:25002532

Vision, visuo-cognition and postural control in Parkinson's disease: An associative pilot study.

PubMed

Hill, E; Stuart, S; Lord, S; Del Din, S; Rochester, L

2016-07-01

Impaired postural control (PC) is common in patients with Parkinson's disease (PD) and is a major contributor to falls, with significant consequences. Mechanisms underpinning PC are complex and include motor and non-motor features. Research has focused predominantly on motor and sensory inputs. Vision and visuo-cognitive function are also integral to PC but have largely been ignored to date. The aim of this observational cross-sectional pilot study was to explore the relationship of vision and visuo-cognition with PC in PD. Twelve people with PD and ten age-matched healthy controls (HC) underwent detailed assessments for vision, visuo-cognition and postural control. Vision assessments included visual acuity and contrast sensitivity. Visuo-cognition was measured by visuo-perception (object identification), visuo-construction (ability to copy a figure) and visuo-spatial ability (judge distances and location of object within environment). PC was measured by an accelerometer for a range of outcomes during a 2-min static stance. Spearman's correlations identified significant associations. Contrast sensitivity, visuo-spatial ability and postural control (ellipsis) were significantly impaired in PD (p=0.017; p=0.001; and p=0.017, respectively). For PD only, significant correlations were found for higher visuo-spatial function and larger ellipsis (r=0.64; p=0.024) and impaired attention and reduced visuo-spatial function (r=-0.62; p=0.028). Visuo-spatial ability is associated with PC deficit in PD, but in an unexpected direction. This suggests a non-linear pattern of response. Further research is required to examine this novel and important finding. Copyright © 2016 Elsevier B.V. All rights reserved.

Topological Valley Transport in Two-dimensional Honeycomb Photonic Crystals.

PubMed

Yang, Yuting; Jiang, Hua; Hang, Zhi Hong

2018-01-25

Two-dimensional photonic crystals, in analogy to AB/BA stacking bilayer graphene in electronic system, are studied. Inequivalent valleys in the momentum space for photons can be manipulated by simply engineering diameters of cylinders in a honeycomb lattice. The inequivalent valleys in photonic crystal are selectively excited by a designed optical chiral source and bulk valley polarizations are visualized. Unidirectional valley interface states are proved to exist on a domain wall connecting two photonic crystals with different valley Chern numbers. With the similar optical vortex index, interface states can couple with bulk valley polarizations and thus valley filter and valley coupler can be designed. Our simple dielectric PC scheme can help to exploit the valley degree of freedom for future optical devices.

KSC-98pc1229

NASA Image and Video Library

1998-10-03

KENNEDY SPACE CENTER, FLA. -- In the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2), the top of the Mars Polar Lander is removed to prepare the Lander for testing, including a functional test of the science instruments and the basic spacecraft subsystems. The Mars Polar Lander is targeted for launch from Cape Canaveral Air Station aboard a Delta II rocket on Jan. 3, 1999. The solar-powered spacecraft is designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere

Polycystin-1 is a Cardiomyocyte Mechanosensor That Governs L-type Ca2+ Channel Protein Stability

PubMed Central

Pedrozo, Zully; Criollo, Alfredo; Battiprolu, Pavan K.; Morales, Cyndi R.; Contreras, Ariel; Fernández, Carolina; Jiang, Nan; Luo, Xiang; Caplan, Michael J.; Somlo, Stefan; Rothermel, Beverly A.; Gillette, Thomas G.; Lavandero, Sergio; Hill, Joseph A.

2015-01-01

Background L-type calcium channel (LTCC) activity is critical to afterload-induced hypertrophic growth of the heart. However, mechanisms governing mechanical stress-induced activation of LTCC activity are obscure. Polycystin-1 (PC-1) is a G-protein-coupled receptor-like protein that functions as a mechanosensor in a variety of cell types and is present in cardiomyocytes. Methods and Results We subjected neonatal rat ventricular myocytes (NRVMs) to mechanical stretch by exposing them to hypo-osmotic (HS) medium or cyclic mechanical stretch, triggering cell growth in a manner dependent on LTCC activity. RNAi-dependent knockdown of PC-1 blocked this hypertrophy. Over-expression of a C-terminal fragment of PC-1 was sufficient to trigger NRVM hypertrophy. Exposing NRVMs to HS medium resulted in an increase in α1C protein levels, a response that was prevented by PC-1 knockdown. MG132, a proteasomal inhibitor, rescued PC-1 knockdown-dependent declines in α1C protein. To test this in vivo, we engineered mice harboring conditional silencing of PC-1 selectively in cardiomyocytes (PC-1 KO) and subjected them to mechanical stress in vivo (transverse aortic constriction, TAC). At baseline, PC-1 KO mice manifested decreased cardiac function relative to littermate controls, and α1C LTCC protein levels were significantly lower in PC-1 KO hearts. Whereas control mice manifested robust TAC-induced increases in cardiac mass, PC-1 KO mice showed no significant growth. Likewise, TAC-elicited increases in hypertrophic markers and interstitial fibrosis were blunted in the knockout animals Conclusions PC-1 is a cardiomyocyte mechanosensor and is required for cardiac hypertrophy through a mechanism that involves stabilization of α1C protein. PMID:25888683

Polycystin-1 Is a Cardiomyocyte Mechanosensor That Governs L-Type Ca2+ Channel Protein Stability.

PubMed

Pedrozo, Zully; Criollo, Alfredo; Battiprolu, Pavan K; Morales, Cyndi R; Contreras-Ferrat, Ariel; Fernández, Carolina; Jiang, Nan; Luo, Xiang; Caplan, Michael J; Somlo, Stefan; Rothermel, Beverly A; Gillette, Thomas G; Lavandero, Sergio; Hill, Joseph A

2015-06-16

L-type calcium channel activity is critical to afterload-induced hypertrophic growth of the heart. However, the mechanisms governing mechanical stress-induced activation of L-type calcium channel activity are obscure. Polycystin-1 (PC-1) is a G protein-coupled receptor-like protein that functions as a mechanosensor in a variety of cell types and is present in cardiomyocytes. We subjected neonatal rat ventricular myocytes to mechanical stretch by exposing them to hypo-osmotic medium or cyclic mechanical stretch, triggering cell growth in a manner dependent on L-type calcium channel activity. RNAi-dependent knockdown of PC-1 blocked this hypertrophy. Overexpression of a C-terminal fragment of PC-1 was sufficient to trigger neonatal rat ventricular myocyte hypertrophy. Exposing neonatal rat ventricular myocytes to hypo-osmotic medium resulted in an increase in α1C protein levels, a response that was prevented by PC-1 knockdown. MG132, a proteasomal inhibitor, rescued PC-1 knockdown-dependent declines in α1C protein. To test this in vivo, we engineered mice harboring conditional silencing of PC-1 selectively in cardiomyocytes (PC-1 knockout) and subjected them to mechanical stress in vivo (transverse aortic constriction). At baseline, PC-1 knockout mice manifested decreased cardiac function relative to littermate controls, and α1C L-type calcium channel protein levels were significantly lower in PC-1 knockout hearts. Whereas control mice manifested robust transverse aortic constriction-induced increases in cardiac mass, PC-1 knockout mice showed no significant growth. Likewise, transverse aortic constriction-elicited increases in hypertrophic markers and interstitial fibrosis were blunted in the knockout animals PC-1 is a cardiomyocyte mechanosensor that is required for cardiac hypertrophy through a mechanism that involves stabilization of α1C protein. © 2015 American Heart Association, Inc.

Improved performance by morphology control via fullerenes in PBDT-TBT-alkoBT based organic solar cells

DOE PAGES

Khatiwada, Devendra; Venkatesan, Swaminathan; Chen, QIliang; ...

2015-07-03

In this work, we report improved performance by controlling morphology using different fullerene derivatives in poly{2-octyldodecyloxy-benzo[1,2-b;3,4-b]dithiophene-alt-5,6-bis(dodecyloxy)-4,7- di(thieno[3,2-b]thiophen-2-yl)-benzo[c][1,2,5]thiadiazole} (PBDT-TBT-alkoBT) based organic solar cells. PC60BM and PC70BM fullerenes were used to investigate the characteristic change in morphology and device performance. Fullerene affects device efficiency by changing active layer morphology. PC70BM with broader absorption than PC 60BM resulted in reduced device performance which was elucidated by the intermixed granular morphology separating each larger grain in the PC70BM/polymer composite layer which created higher density of traps. However after adding additive 1,8-diiodooctane (DIO), the fibrous morphology was observed due to reduced solubility of polymer andmore » increased solubility of PC 70BM in chloroform. The fibrous morphology improved charge transport leading to increase in overall device performance. Atomic force microscopies (AFM), photo induced charge extraction by linearly increasing voltage (photo-CELIV), and Kelvin prove force microscope (KPFM) were used to investigate nanoscale morphology of active layer with different fullerene derivatives. For PC 60BM based active layer, AFM images revealed dense fibrous morphology and more distinct fibrous morphology was observed by adding DIO. The PC 70BM based active layer only exhibited intermixed granular morphology instead of fibrous morphology observed in PC60BM based active layer. However, addition of DIO in PC 70BM based active layer led to fibrous morphology. When additive DIO was not used, a wider distribution of surface potential was observed for PC 70BM than PC 60BM based active layer by KPFM measurements, indicating 2 polymer and fullerene domains are separated. When DIO was used, narrower distribution of surface potential for both PC 70BM and PC 60BM based active layers was observed. Photo-CELIV experiment showed larger extracted charge carrier density and mobility in PC 70BM/DIO film.« less

Improved performance by morphology control via fullerenes in PBDT-TBT-alkoBT based organic solar cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khatiwada, Devendra; Venkatesan, Swaminathan; Chen, QIliang

In this work, we report improved performance by controlling morphology using different fullerene derivatives in poly{2-octyldodecyloxy-benzo[1,2-b;3,4-b]dithiophene-alt-5,6-bis(dodecyloxy)-4,7- di(thieno[3,2-b]thiophen-2-yl)-benzo[c][1,2,5]thiadiazole} (PBDT-TBT-alkoBT) based organic solar cells. PC60BM and PC70BM fullerenes were used to investigate the characteristic change in morphology and device performance. Fullerene affects device efficiency by changing active layer morphology. PC70BM with broader absorption than PC 60BM resulted in reduced device performance which was elucidated by the intermixed granular morphology separating each larger grain in the PC70BM/polymer composite layer which created higher density of traps. However after adding additive 1,8-diiodooctane (DIO), the fibrous morphology was observed due to reduced solubility of polymer andmore » increased solubility of PC 70BM in chloroform. The fibrous morphology improved charge transport leading to increase in overall device performance. Atomic force microscopies (AFM), photo induced charge extraction by linearly increasing voltage (photo-CELIV), and Kelvin prove force microscope (KPFM) were used to investigate nanoscale morphology of active layer with different fullerene derivatives. For PC 60BM based active layer, AFM images revealed dense fibrous morphology and more distinct fibrous morphology was observed by adding DIO. The PC 70BM based active layer only exhibited intermixed granular morphology instead of fibrous morphology observed in PC60BM based active layer. However, addition of DIO in PC 70BM based active layer led to fibrous morphology. When additive DIO was not used, a wider distribution of surface potential was observed for PC 70BM than PC 60BM based active layer by KPFM measurements, indicating 2 polymer and fullerene domains are separated. When DIO was used, narrower distribution of surface potential for both PC 70BM and PC 60BM based active layers was observed. Photo-CELIV experiment showed larger extracted charge carrier density and mobility in PC 70BM/DIO film.« less

Texturing of sodium bismuth titanate-barium titanate ceramics by templated grain growth

NASA Astrophysics Data System (ADS)

Yilmaz, Huseyin

2002-01-01

Sodium bismuth titanate modified with barium titanate, (Na1/2Bi 1/2)TiO3-BaTiO3 (NBT-BT), is a candidate lead-free piezoelectric material which has been shown to have comparatively high piezoelectric response. In this work, textured (Na1/2Bi1/2)TiO 3-BaTiO3 (5.5mol% BaTiO3) ceramics with <100> pc (where pc denotes the pseudocubic perovskite cell) orientation were fabricated by Templated Grain Growth (TGG) or Reactive Templated Grain Growth (RTGG) using anisotropically shaped template particles. In the case of TGG, molten salt synthesized SrTiO3 platelets were tape cast with a (Na1/2Bi1/2)TiO3-5.5mol%BaTiO3 powder and sintered at 1200°C for up to 12 hours. For the RTGG approach, Bi4Ti3O12 (BiT) platelets were tape cast with a Na2CO3, Bi2O3, TiO 2, and BaCO3 powder mixture and reactively sintered. The TGG approach using SrTiO3 templates gave stronger texture along [001] compared to the RTGG approach using BiT templates. The textured ceramics were characterized by X-ray and electron backscatter diffraction for the quality of texture. The texture function was quantified by the Lotgering factor, rocking curve, pole figures, inverse pole figures, and orientation imaging microscopy. Electrical and electromechanical property characterization of randomly oriented and <001>pc textured (Na1/2Bi1/2)TiO 3-5.5 mol% BaTiO3 rhombohedral ceramics showed 0.26% strain at 70 kV/cm, d33 coefficients over 500 pC/N have been obtained for highly textured samples (f ˜ 90%). The piezoelectric coefficient from Berlincourt was d33 ˜ 200 pC/N. The materials show considerable hysteresis. The presence of hysteresis in the unipolar-electric field curve is probably linked to the ferroelastic phase transition seen in the (Na 1/2Bi1/2)TiO3 system on cooling from high temperature at ˜520°C. The macroscopic physical properties (remanent polarization, dielectric constant, and piezoelectric coefficient) of random and textured ([001] pc) rhombohedral perovskites were estimated by linear averaging of single crystal data. However, the complete polarization, dielectric, and piezoelectric tensors are not available for NBT-BT single crystals. Therefore, the properties of lead based (PZT, 52/48) rhombohedral ferroelectric single domain-single crystals, whose properties (polarization, dielectric and piezoelectric) were computed using Landau-Ginsburg-Devonshire phenomenological theory (by Haun et. al.), were used in the calculations for random and textured cases. (Abstract shortened by UMI.)

Controllable fabrication of copper phthalocyanine nanostructure crystals.

PubMed

Liu, Fangmei; Sun, Jia; Xiao, Si; Huang, Wenglong; Tao, Shaohua; Zhang, Yi; Gao, Yongli; Yang, Junliang

2015-06-05

Copper phthalocyanine (CuPc) nanostructure crystals, including nanoflower, nanoribbon, and nanowire, were controllably fabricated by temperature gradient physical vapor deposition (TG-PVD) through controlling the growth parameters. In a controllable growth system with carrier gas N2, nanoflower, nanoribbon, and nanowire crystals were formed in a high-temperature zone, medium-temperature zone, and low-temperature zone, respectively. They were proved to be β-phase, coexist of α-phase and β-phase, and α-phase respectively based on x-ray diffraction results. Furthermore, ultralong CuPc nanowires up to several millimeters could be fabricated by TG-PVD without carrier gas, and they were well-aligned to form large-area CuPc nanowire crystal arrays by the Langmuir-Blodgett method. The nanostructure crystals showed unusual optical absorption spectra from the ultraviolet-visible to near-infrared range, which was explained by the diffraction and scattering caused by the wavelength-sized nanostructures. These CuPc nanostructure crystals show potential applications in organic electronic and optoelectronic devices.

PcFKH1, a novel regulatory factor from the forkhead family, controls the biosynthesis of penicillin in Penicillium chrysogenum.

PubMed

Domínguez-Santos, Rebeca; García-Estrada, Carlos; Kosalková, Katarina; Prieto, Carlos; Santamarta, Irene; Martín, Juan-Francisco

2015-08-01

Penicillin biosynthesis in Penicillium chrysogenum (re-identified as Penicillium rubens) is a good example of a biological process subjected to complex global regulatory networks and serves as a model to study fungal secondary metabolism. The winged-helix family of transcription factors recently described, which includes the forkhead type of proteins, is a key type of regulatory proteins involved in this process. In yeasts and humans, forkhead transcription factors are involved in different processes (cell cycle regulation, cell death control, pre-mRNA processing and morphogenesis); one member of this family of proteins has been identified in the P. chrysogenum genome (Pc18g00430). In this work, we have characterized this novel transcription factor (named PcFKH1) by generating knock-down mutants and overexpression strains. Results clearly indicate that PcFKH1 positively controls antibiotic biosynthesis through the specific interaction with the promoter region of the penDE gene, thus regulating penDE mRNA levels. PcFKH1 also binds to the pcbC promoter, but with low affinity. In addition, it also controls other ancillary genes of the penicillin biosynthetic process, such as phlA (encoding phenylacetyl CoA ligase) and ppt (encoding phosphopantetheinyl transferase). PcFKH1 also plays a role in conidiation and spore pigmentation, but it does not seem to be involved in hyphal morphology or cell division in the improved laboratory reference strain Wisconsin 54-1255. A genome-wide analysis of processes putatively coregulated by PcFKH1 and PcRFX1 (another winged-helix transcription factor) in P. chrysogenum provided evidence of the global effect of these transcription factors in P. chrysogenum metabolism. Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

Influence of molecular geometry, exchange-correlation functional, and solvent effects in the modeling of vertical excitation energies in phthalocyanines using time-dependent density functional theory (TDDFT) and polarized continuum model TDDFT methods: can modern computational chemistry methods explain experimental controversies?

PubMed

Nemykin, Victor N; Hadt, Ryan G; Belosludov, Rodion V; Mizuseki, Hiroshi; Kawazoe, Yoshiyuki

2007-12-20

A time-dependent density functional theory (TDDFT) approach coupled with 14 different exchange-correlation functionals was used for the prediction of vertical excitation energies in zinc phthalocyanine (PcZn). In general, the TDDFT approach provides a more accurate description of both visible and ultraviolet regions of the UV-vis and magnetic circular dichroism (MCD) spectra of PcZn in comparison to the more popular semiempirical ZINDO/S and PM3 methods. It was found that the calculated vertical excitation energies of PcZn correlate with the amount of Hartree-Fock exchange involved in the exchange-correlation functional. The correlation was explained on the basis of the calculated difference in energy between occupied and unoccupied molecular orbitals. The influence of PcZn geometry, optimized using different exchange-correlation functionals, on the calculated vertical excitation energies in PcZn was found to be relatively small. The influence of solvents on the calculated vertical excitation energies in PcZn was considered for the first time using a polarized continuum model TDDFT (PCM-TDDFT) method and was found to be relatively small in excellent agreement with the experimental data. For all tested TDDFT and PCM-TDDFT cases, an assignment of the Q-band as an almost pure a1u (HOMO)-->eg (LUMO) transition, initially suggested by Gouterman, was confirmed. Pure exchange-correlation functionals indicate the presence of six 1Eu states in the B-band region of the UV-vis spectrum of PcZn, while hybrid exchange-correlation functionals predict only five 1Eu states for the same energy envelope. The first two symmetry-forbidden n-->pi* transitions were predicted in the Q0-2 region and in the low-energy tail of the B-band, while the first two symmetry-allowed n-->pi* transitions were found within the B-band energy envelope when pure exchange-correlation functionals were used for TDDFT calculations. The presence of a symmetry-forbidden but vibronically allowed n-->pi* transition in the Q0-2 spectral envelope explains the long-time controversy between the experimentally observed low-intensity transition in the Q0-2 region and previous semiempirical and TDDFT calculations, which were unable to predict any electronic transitions in this area. To prove the conceptual possibility of the presence of several degenerate 1Eu states in the B-band region of PcZn, room-temperature UV-vis and MCD spectra of zinc tetra-tert-butylphthalocyanine (PctZn) in non-coordinating solvents were recorded and analyzed using band deconvolution analysis. It was found that the B-band region of the UV-vis and MCD spectra of PctZn can be easily deconvoluted using six MCD Faraday A-terms and two MCD Faraday B-terms with energies close to those predicted by TDDFT calculations for 1Eu and 1A2u excited states, respectively. Such a good agreement between theory and experiment clearly indicates the possibility of employing a TDDFT approach for the accurate prediction of vertical excitation energies in phthalocyanines within a large energy range.

The auditory comprehension changes over time after sport-related concussion can indicate multisensory processing dysfunctions.

PubMed

Białuńska, Anita; Salvatore, Anthony P

2017-12-01

Although science findings and treatment approaches of a concussion have changed in recent years, there continue to be challenges in understanding the nature of the post-concussion behavior. There is growing a body of evidence that some deficits can be related to an impaired auditory processing. To assess auditory comprehension changes over time following sport-related concussion (SRC) in young athletes. A prospective, repeated measures mixed-design was used. A sample of concussed athletes ( n  = 137) and the control group consisted of age-matched, non-concussed athletes ( n  = 143) were administered Subtest VIII of the Computerized-Revised Token Test (C-RTT). The 88 concussed athletes selected for final analysis (neither previous history of brain injury, neurological, psychiatric problems, nor auditory deficits) were evaluated after injury during three sessions (PC1, PC2, and PC3); controls were tested once. Between- and within-group comparisons using RMANOVA were performed on the C-RTT Efficiency Score (ES). ES of the SRC athletes group improved over consecutive testing sessions ( F  =   14.7, p  <   .001), while post-hoc analysis showed that PC1 results differed from PC2 and PC3 ( ts  ≥ 4.0, ps  < .001), but PC2 and PC3 C-RTT ES did not change statistically ( t  =   0.6, p =  .557). The SRC athletes demonstrated lower ES for all test session when compared to the control group ( ts  > 2.0, Ps <.01). Dysfunctional auditory comprehension performance following a concussion improved over time, but after the second testing session improved performance slowed, especially in terms of its timing. Yet, not only auditory processing but also sensorimotor integration and/or motor execution can be compromised after a concussion.

Reconciling the effects of screening on prostate cancer mortality in the ERSPC and PLCO trials

PubMed Central

Tsodikov, Alex; Gulati, Roman; Heijnsdijk, Eveline AM; Pinsky, Paul F; Moss, Sue M; Qiu, Sheng; de Carvalho, Tiago M; Hugosson, Jonas; Berg, Christine D; Auvinen, Anssi; Andriole, Gerald L; Roobol, Monique J; Crawford, E David; Nelen, Vera; Kwiatkowski, Maciej; Zappa, Marco; Luján, Marcos; Villers, Arnauld; Feuer, Eric J; de Koning, Harry J; Mariotto, Angela B; Etzioni, Ruth

2017-01-01

Background The European Randomized Study of Screening for Prostate Cancer (ERSPC) found screening reduced prostate cancer (PC) mortality, but the Prostate, Lung, Colorectal, and Ovarian trial (PLCO) found no reduction. Objective To evaluate whether effects of screening on PC mortality relative to no screening differed between the ERSPC and PLCO. Design Cox regression of PC death in each trial arm adjusted for age and trial, and extended analyses that accounted for increased incidence due to screening and diagnostic workup on each arm via mean lead times (MLTs). MLTs were estimated empirically and using analytic or microsimulation models. Setting Randomized controlled trials in Europe and the US. Participants Men aged 55–69 (ERSPC) or 55–74 (PLCO) at randomization. Intervention Prostate cancer screening. Measurements PC incidence and survival from randomization; PC incidence in the US before screening began. Results Estimated MLTs were similar in the ERSPC and PLCO intervention arms but were longer in the PLCO control arm than the ERSPC control arm. Extended analyses found no evidence that effects of screening differed between trials (P=0.37–0.47, range across MLT estimation approaches) but strong evidence that benefit increased with MLT (P=0.0027–0.0032). Screening was estimated to confer a 7–9% reduction in PC death per year of MLT. This translated into an estimated 25–31% and 27–32% lower risk of PC death under screening as performed in the ERSPC and PLCO intervention arms, respectively, relative to no screening. Limitations MLT is a simple metric of screening and diagnostic workup. Conclusion After accounting for differences in implementation and settings, the ERSPC and PLCO provide compatible evidence that screening reduces PC mortality. PMID:28869989

Anaplerotic roles of pyruvate carboxylase in mammalian tissues.

PubMed

Jitrapakdee, S; Vidal-Puig, A; Wallace, J C

2006-04-01

Pyruvate carboxylase (PC) catalyzes the ATP-dependent carboxylation of pyruvate to oxaloacetate. PC serves an anaplerotic role for the tricarboxylic acid cycle, when intermediates are removed for different biosynthetic purposes. In liver and kidney, PC provides oxaloacetate for gluconeogenesis. In adipocytes PC is involved in de novo fatty acid synthesis and glyceroneogenesis, and is regulated by the peroxisome proliferator-activated receptor-gamma, suggesting that PC is involved in the metabolic switch controlling fuel partitioning toward lipogenesis. In islets, PC is necessary for glucose-induced insulin secretion by providing oxaloacetate to form malate that participates in the 'pyruvate/malate cycle' to shuttle 3C or 4C between mitochondria and cytoplasm. Hyperglycemia and hyperlipidemia impair this cycle and affect glucose-stimulated insulin release. In astrocytes, PC is important for de novo synthesis of glutamate, an important excitatory neurotransmitter supplied to neurons. Transcriptional studies of the PC gene pinpoint some transcription factors that determine tissue-specific expression.

Human pancreatic cancer xenografts recapitulate key aspects of cancer cachexia.

PubMed

Delitto, Daniel; Judge, Sarah M; Delitto, Andrea E; Nosacka, Rachel L; Rocha, Fernanda G; DiVita, Bayli B; Gerber, Michael H; George, Thomas J; Behrns, Kevin E; Hughes, Steven J; Wallet, Shannon M; Judge, Andrew R; Trevino, Jose G

2017-01-03

Cancer cachexia represents a debilitating syndrome that diminishes quality of life and augments the toxicities of conventional treatments. Cancer cachexia is particularly debilitating in patients with pancreatic cancer (PC). Mechanisms responsible for cancer cachexia are under investigation and are largely derived from observations in syngeneic murine models of cancer which are limited in PC. We evaluate the effect of human PC cells on both muscle wasting and the systemic inflammatory milieu potentially contributing to PC-associated cachexia. Specifically, human PC xenografts were generated by implantation of pancreatic cancer cells, L3.6pl and PANC-1, either in the flank or orthotopically within the pancreas. Mice bearing orthotopic xenografts demonstrated significant muscle wasting and atrophy-associated gene expression changes compared to controls. Further, despite the absence of adaptive immunity, splenic tissue from orthotopically engrafted mice demonstrated elevations in several pro-inflammatory cytokines associated with cancer cachexia, including TNFα, IL1β, IL6 and KC (murine IL8 homologue), when compared to controls. Therefore, data presented here support further investigation into the complexity of cancer cachexia in PC to identify potential targets for this debilitating syndrome.

Metabolic system alterations in pancreatic cancer patient serum: potential for early detection

PubMed Central

2013-01-01

Background The prognosis of pancreatic cancer (PC) is one of the poorest among all cancers, due largely to the lack of methods for screening and early detection. New biomarkers for identifying high-risk or early-stage subjects could significantly impact PC mortality. The goal of this study was to find metabolic biomarkers associated with PC by using a comprehensive metabolomics technology to compare serum profiles of PC patients to healthy control subjects. Methods A non-targeted metabolomics approach based on high-resolution, flow-injection Fourier transform ion cyclotron resonance mass spectrometry (FI-FTICR-MS) was used to generate comprehensive metabolomic profiles containing 2478 accurate mass measurements from the serum of Japanese PC patients (n=40) and disease-free subjects (n=50). Targeted flow-injection tandem mass spectrometry (FI-MS/MS) assays for specific metabolic systems were developed and used to validate the FI-FTICR-MS results. A FI-MS/MS assay for the most discriminating metabolite discovered by FI-FTICR-MS (PC-594) was further validated in two USA Caucasian populations; one comprised 14 PCs, six intraductal papillary mucinous neoplasims (IPMN) and 40 controls, and a second comprised 1000 reference subjects aged 30 to 80, which was used to create a distribution of PC-594 levels among the general population. Results FI-FTICR-MS metabolomic analysis showed significant reductions in the serum levels of metabolites belonging to five systems in PC patients compared to controls (all p<0.000025). The metabolic systems included 36-carbon ultra long-chain fatty acids, multiple choline-related systems including phosphatidylcholines, lysophosphatidylcholines and sphingomyelins, as well as vinyl ether-containing plasmalogen ethanolamines. ROC-AUCs based on FI-MS/MS of selected markers from each system ranged between 0.93 ±0.03 and 0.97 ±0.02. No significant correlations between any of the systems and disease-stage, gender, or treatment were observed. Biomarker PC-594 (an ultra long-chain fatty acid), was further validated using an independently-collected US Caucasian population (blinded analysis, n=60, p=9.9E-14, AUC=0.97 ±0.02). PC-594 levels across 1000 reference subjects showed an inverse correlation with age, resulting in a drop in the AUC from 0.99 ±0.01 to 0.90 ±0.02 for subjects aged 30 to 80, respectively. A PC-594 test positivity rate of 5.0% in low-risk reference subjects resulted in a PC sensitivity of 87% and a significant improvement in net clinical benefit based on decision curve analysis. Conclusions The serum metabolome of PC patients is significantly altered. The utility of serum metabolite biomarkers, particularly PC-594, for identifying subjects with elevated risk of PC should be further investigated. PMID:24024929

Limb-bud and Heart Overexpression Inhibits the Proliferation and Migration of PC3M Cells.

PubMed

Liu, Qicai; Li, Ermao; Huang, Long; Cheng, Minsheng; Li, Li

2018-01-01

Background: The limb-bud and heart gene ( LBH ) was discovered in the early 21st century and is specifically expressed in the mouse embryonic limb and heart development. Increasing evidences have indicated that LBH not only plays an important role in embryo development, it is also closely correlated with the occurance and progression of many tumors. However, its function in prostate cancer (PCa) is still not well understood. Here, we explored the effects of LBH on the proliferation and migration of the PCa cell line PC3M. Methods: LBH expression in tissues and cell lines of PCa was detected by immunohistochemistry and Western blotting. Lentivirus was used to transduct the LBH gene into the PC3M cells. Stable LBH-overexpressing PC3M-LBH cells and PC3M-NC control cells were obtained via puromycin screening. Cell proliferation was examined using the 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Cell cycle distribution and apoptosis rate were investigated using flow cytometry. Cell migration was studied using the Transwell assay. Results: LBH expression level was down-regulated in 3 different PCa cell lines, especially in PC3M cells, compared with the normal prostate epithelial cells(RWPE-1). Cell lines of LBH-upregulated PC3M-LBH and PC3M-NC control were successfully constructed. Significantly increased LBH expression level and decreased cyclin D1 and cyclin E2 expression level was found in PC3M-LBH cells as compared to the PC3M-NC cells. The overexpression of LBH significantly inhibited PC3M cell proliferation in vitro and tumor growth in nude mice. LBH overexpression in PC3M cell, also induced cell cycle G0/G1 phase arrest and decreased the migration of PC3M cells. Conclusions : Our results reveal that LBH expression is down-regulated in the tissue and cell lines of PCa. LBH overexpression inhibits PC3M cell proliferation and tumor growth by inducing cell cycle arrest through down-regulating cyclin D1and cyclin E2 expression. LBH might be a therapeutic target and potential diagnostic marker in PCa.

HDAC Inhibition Induces Increased Choline Uptake and Elevated Phosphocholine Levels in MCF7 Breast Cancer Cells

PubMed Central

Ward, Christopher S.; Eriksson, Pia; Izquierdo-Garcia, Jose L.; Brandes, Alissa H.; Ronen, Sabrina M.

2013-01-01

Histone deacetylase (HDAC) inhibitors have emerged as effective antineoplastic agents in the clinic. Studies from our lab and others have reported that magnetic resonance spectroscopy (MRS)-detectable phosphocholine (PC) is elevated following SAHA treatment, providing a potential noninvasive biomarker of response. Typically, elevated PC is associated with cancer while a decrease in PC accompanies response to antineoplastic treatment. The goal of this study was therefore to elucidate the underlying biochemical mechanism by which HDAC inhibition leads to elevated PC. We investigated the effect of SAHA on MCF-7 breast cancer cells using 13C MRS to monitor [1,2-13C] choline uptake and phosphorylation to PC. We found that PC synthesis was significantly higher in treated cells, representing 154±19% of control. This was within standard deviation of the increase in total PC levels detected by 31P MRS (129±7% of control). Furthermore, cellular choline kinase activity was elevated (177±31%), while cytidylyltransferase activity was unchanged. Expression of the intermediate-affinity choline transporter SLC44A1 and choline kinase α increased (144% and 161%, respectively) relative to control, as determined by mRNA microarray analysis with protein-level confirmation by Western blotting. Taken together, our findings indicate that the increase in PC levels following SAHA treatment results from its elevated synthesis. Additionally, the concentration of glycerophosphocholine (GPC) increased significantly with treatment to 210±45%. This is likely due to the upregulated expression of several phospholipase A2 (PLA2) isoforms, resulting in increased PLA2 activity (162±18%) in SAHA-treated cells. Importantly, the levels of total choline (tCho)-containing metabolites, comprised of choline, PC and GPC, are readily detectable clinically using 1H MRS. Our findings thus provide an important step in validating clinically translatable non-invasive imaging methods for follow-up diagnostics of HDAC inhibitor treatment. PMID:23626839

Gut microbial profile analysis by MiSeq sequencing of pancreatic carcinoma patients in China

PubMed Central

Xie, Haiyang; Li, Ang; Lu, Haifeng; Xu, Shaoyan; Zhou, Lin; Zhang, Hua; Cui, Guangying; Chen, Xinhua; Liu, Yuanxing; Wu, Liming; Qin, Nan; Sun, Ranran; Wang, Wei; Li, Lanjuan; Wang, Weilin; Zheng, Shusen

2017-01-01

Pancreatic carcinoma (PC) is a lethal cancer. Gut microbiota is associated with some risk factors of PC, e.g. obesity and types II diabetes. However, the specific gut microbial profile in clinical PC in China has never been reported. This prospective study collected 85 PC and 57 matched healthy controls (HC) to analyze microbial characteristics by MiSeq sequencing. The results showed that gut microbial diversity was decreased in PC with an unique microbial profile, which partly attributed to its decrease of alpha diversity. Microbial alterations in PC featured by the increase of certain pathogens and lipopolysaccharides-producing bacteria, and the decrease of probiotics and butyrate-producing bacteria. Microbial community in obstruction cases was separated from the un-obstructed cases. Streptococcus was associated with the bile. Furthermore, 23 microbial functions e.g. Leucine and LPS biosynthesis were enriched, while 13 functions were reduced in PC. Importantly, based on 40 genera associated with PC, microbial markers achieves a high classification power with AUC of 0.842. In conclusion, gut microbial profile was unique in PC, providing a microbial marker for non-invasive PC diagnosis. PMID:29221120

[Toxicity of Pythium oligandrum broth to animal and its control effect on rot diseases caused by Penicillium italicum and Penicillium digitatum in orange fruit storage].

PubMed

Tan, Yan; Peng, Liangzhi; Yuan, Ling; Wang, Shaobo

2015-11-04

In order to develop a safe, nontoxic and efficient biological antistaling agent and to decrease the incidence of rot diseases caused by the Penicillium italicum and Penicillium digitatum in orange fruit storage. the present experiment was carried out with Pythium oligandrum broth (POB) produced by our self-isolated strain (P. oligandrum CQ2010) to study the toxicity to animal. Thereafter, mycelium growth and spore germination of both P. digitatum and P. italicum and control effect of rot disease in orange storage were compared after treated by liquid culture medium (control), POB, prochloraz (PC) , and PC + POB. Gastric lavage with large amount POB did not influence mouse weight. The animals also showed no abnormality in appearance, behaviors and pathology changes in heart, liver, kidney, lung and intestine. POB decreased the hyphal growth by 70.24% - 93.74% and spore germination by 44.91% - 87.82% (24 h after POB addition) of these two pathogenic fungi. Disease incidence of orange fruit following P. italicum inoculation changed in the sequence: CK > POB > PC > PC + POB and the control efficacy behaved otherwise. In commercial simulation storage, the disease incidence of orange fruit caused by P. digitatum and P. italicum was above 50% of the total. The fruit rot rate was 26.40% (CK), 15.03% (POB), 16.61% (PC) and 4.21% (PC + POB). There were no significant differences in fruit quality under different treatments. POB was safe to animal and could decrease rot disease incidence caused by P. italicum and P. digitatum in orange storage whereby producing a positive interaction with prochloraz and controlling rot diseases caused by these two fungi.

Gene Expression Profiling in Pachyonychia Congenita Skin

PubMed Central

Cao, Yu-An; Hickerson, Robyn P.; Seegmiller, Brandon L.; Grapov, Dmitry; Gross, Maren M.; Bessette, Marc R.; Phinney, Brett S.; Flores, Manuel A.; Speaker, Tycho J.; Vermeulen, Annaleen; Bravo, Albert A.; Bruckner, Anna L.; Milstone, Leonard M.; Schwartz, Mary E.; Rice, Robert H.; Kaspar, Roger L.

2015-01-01

Background Pachyonychia congenita (PC) is a skin disorder resulting from mutations in keratin (K) proteins including K6a, K6b, K16, and K17. One of the major symptoms is painful plantar keratoderma. The pathogenic sequelae resulting from the keratin mutations remain unclear. Objective To better understand PC pathogenesis. Methods RNA profiling was performed on biopsies taken from PC-involved and uninvolved plantar skin of seven genotyped PC patients (two K6a, one K6b, three K16, and one K17) as well as from control volunteers. Protein profiling was generated from tape-stripping samples. Results A comparison of PC-involved skin biopsies to adjacent uninvolved plantar skin identified 112 differentially-expressed mRNAs common to patient groups harboring K6 (i.e., both K6a and K6b) and K16 mutations. Among these mRNAs, 25 encode structural proteins including keratins, small proline-rich and late cornified envelope proteins, 20 are related to metabolism and 16 encode proteases, peptidases, and their inhibitors including kallikrein-related peptidases (KLKs), and serine protease inhibitors (SERPINs). mRNAs were also identified to be differentially expressed only in K6 (81) or K16 (141) patient samples. Furthermore, 13 mRNAs were identified that may be involved in pain including nociception and neuropathy. Protein profiling, comparing three K6a plantar tape-stripping samples to non-PC controls, showed changes in the PC corneocytes similar, but not identical, to the mRNA analysis. Conclusion Many differentially-expressed genes identified in PC-involved skin encode components critical for skin barrier homeostasis including keratinocyte proliferation, differentiation, cornification, and desquamation. The profiling data provide a foundation for unraveling the pathogenesis of PC and identifying targets for developing effective PC therapeutics. PMID:25656049

Lac-L-TTA, a novel lactose-based amino acid-sugar conjugate for anti-metastatic applications.

PubMed

Roviello, Giovanni N; Iannitti, Roberta; Palumbo, Rosanna; Simonyan, Hayarpi; Vicidomini, Caterina; Roviello, Valentina

2017-08-01

Here we describe the synthesis, chromatographic purification, MS and NMR characterization of a new lactosyl-derivative, i.e. a lactosyl thiophenyl-substituted triazolyl-thione L-alanine (Lac-L-TTA). This amino acid-sugar conjugate was prepared by solution synthesis in analogy to the natural fructosyl-amino acids. Furthermore, we investigated the inhibition of PC-3 prostate cancer cell colony formation by this lactose derivative in comparison with the less polar fructose-based derivative, Fru-L-TTA. This let us to compare the properties of the artificial derivative, object of the present work, with the monosaccharide-based counterpart and to obtain a preliminary information on the influence of polarity on such biological activity. A significantly higher anticancer effect of Lac-L-TTA with respect to the fructose analogue emerged from our study suggesting that the anti-metastatic potential of fructosyl-amino acids can be enhanced by increasing the polarity of the compounds, for example by introducing disaccharide moieties in place of fructose.

[Relationship between chronic prostatitis and prostatic calculus].

PubMed

Chen, Hong-jie; Yang, Ning-gang; Zhang, Ju-jie; Wang, Jun; Zhang, Xiang-jun; Zhang, Jun; Yu, Xin-ning; Zhang, Dian-ting

2011-01-01

To explore the relationship between chronic prostatitis (CP) and prostatic calculus (PC). We used transperineal ultrasonography (TPUS) to detect PC in 500 normal volunteers and 491 CP patients, and divided them into a CP and a CP + PC group according to the ultrasonographic results. Then we analyzed the NIH-CPSI scores, duration of symptoms and white blood cell count in the expressed prostate secretion (ESP). PC was found in 19.8% of the normal controls, 5% (5/100), 12% (12/100), 19% (19/100), 27% (27/100) and 36% (36/100) in the 20-30 yr, 31-40 yr, 41-50 yr, 51-60 yr and > 60 yr groups, respectively. In comparison, PC was detected in 42.2% of the CP patients, 15.8% (12/76), 30.1% (69/215), 55.7% (59/109), 66.2% (43/65) and 82.8% (24/29) in the above five age groups, respectively, with statistically significant differences between the control and CP groups (P < 0.01). The CP and CP + PC groups showed significant differences in the duration of symptoms and white blood cell count in ESP (P < 0.01) but not in CPSI scores (P < 0.05). The incidence of PC is higher in CP patients than in healthy men, and it is associated with inflammation, aging and symptom duration, but not with CPSI scores.

GPI-anchored proteins are confined in subdiffraction clusters at the apical surface of polarized epithelial cells

PubMed Central

Paladino, Simona; Lebreton, Stéphanie; Lelek, Mickaël; Riccio, Patrizia; De Nicola, Sergio; Zimmer, Christophe

2017-01-01

Spatio-temporal compartmentalization of membrane proteins is critical for the regulation of diverse vital functions in eukaryotic cells. It was previously shown that, at the apical surface of polarized MDCK cells, glycosylphosphatidylinositol (GPI)-anchored proteins (GPI-APs) are organized in small cholesterol-independent clusters of single GPI-AP species (homoclusters), which are required for the formation of larger cholesterol-dependent clusters formed by multiple GPI-AP species (heteroclusters). This clustered organization is crucial for the biological activities of GPI-APs; hence, understanding the spatio-temporal properties of their membrane organization is of fundamental importance. Here, by using direct stochastic optical reconstruction microscopy coupled to pair correlation analysis (pc-STORM), we were able to visualize and measure the size of these clusters. Specifically, we show that they are non-randomly distributed and have an average size of 67 nm. We also demonstrated that polarized MDCK and non-polarized CHO cells have similar cluster distribution and size, but different sensitivity to cholesterol depletion. Finally, we derived a model that allowed a quantitative characterization of the cluster organization of GPI-APs at the apical surface of polarized MDCK cells for the first time. Experimental FRET (fluorescence resonance energy transfer)/FLIM (fluorescence-lifetime imaging microscopy) data were correlated to the theoretical predictions of the model. PMID:29046391

Polarization due to dust scattering in the planetary nebula Cn1-1

NASA Technical Reports Server (NTRS)

Bhatt, Harish C.

1989-01-01

The peculiar emission-line object Cn1-1 (=HDE330036=PK330+4 degrees 1), classified both as a symbiotic star and as a planetary nebula, was detected by the Infrared Astronomical Satellite (IRAS) as a strong source of far-infrared dust in the system. Bhatt and Mallik (1986) discussed the nature of the dust in Cn1-1 and argued that the object is a Type I protoplanetary nebula in a binary system. The argument presented here is that the polarization is intrinsic to Cn1-1 and is due to scattering by large (compared to interstellar) dust grains in the protoplanetary nebula that are asymmetrically distributed around the central star. The large degree of polarization (approximately 3 percent for the Cn1-1 distance of approximately 450 pc) with a large lambda(sub max) is naturally explained if it is caused by scattering by large dust grains in the Cn1-1 nebula. Since the H(sub alpha) line is also polarized at the same level and position angle as the continuum, the dust must be asymmetrically distributed around the central star. The morphology of the protoplanetary nebula in Cn1-1 may be bipolar. Thus, the polarization observations support the suggestion that Cn1-1 is a bipolar Type I planetary nebula.

Fabrication, polarization, and characterization of PVDF matrix composites for integrated structural load sensing

NASA Astrophysics Data System (ADS)

Haghiashtiani, Ghazaleh; Greminger, Michael A.

2015-04-01

The focus of this work is to evaluate a new carbon fiber reinforced composite structure with integrated sensing capabilities. In this composite structure, the typical matrix material used for carbon fiber reinforced composites is replaced with the thermoplastic polyvinylidene difluoride (PVDF). Since PVDF has piezoelectric properties, it enables the structure to be used for integrated load sensing. In addition, the electrical conductivity property of the carbon fabric is harnessed to form the electrodes of the integrated sensor. In order to prevent the carbon fiber electrodes from shorting to each other, a thin Kevlar fabric layer is placed between the two carbon fiber electrode layers as a dielectric. The optimal polarization parameters were determined using a design of experiments approach. Once polarized, the samples were then used in compression and tensile tests to determine the effective d33 and d31 piezoelectric coefficients. The degree of polarization of the PVDF material was determined by relating the effective d33 coefficient of the composite to the achieved d33 of the PVDF component of the composite using a closed form expression. Using this approach, it was shown that optimal polarization of the composite material results in a PVDF component d33 of 3.2 pC N-1. Moreover, the Young’s modulus of the composite structure has been characterized.

Use of insoluble polyacrylate polymers to aid phytostabilization of mine soils: effects on plant growth and soil characteristics.

PubMed

Qu, G; de Varennes, A; Cunha-Queda, C

2010-01-01

We evaluated the use of polyacrylate polymers to aid phytostabilization of mine soils. In a pot experiment, perennial ryegrass was grown in a mine soil and in uncontaminated soil. Growth was stimulated in the polymer-amended mine soil compared with an unamended control, and water-extractable levels of soil Cu and Zn decreased after polymer application. In an experiment performed in six 60-cm-diameter cylinders filled with fertilized mine soil, polymers were applied to three cylinders, with the remainder used as unamended control. Total biomass produced by indigenous plant species sown in polymer-amended soil was 1.8 (Spring-Summer) or 2.4 times (Fall-Winter) greater than that of plants from unamended soil. The application of polymers to the mine soil led to the greatest activity of soil enzymes. Soil pH, biomass of Spergularia purpurea and Chaetopogon fasciculatus, and activities of protease and cellulase had large loadings on principal component (PC)1, whereas growth of Briza maxima and the activities of urease, acid phosphatase, and beta-glucosidase had large loadings on PC2. The treatments corresponding to controls were located on the negative side of PC1 and PC2. Amended treatments were on the positive side of PC2 (Spring-Summer) or on the positive side of PC1 (Fall-Winter), demonstrating differential responses of plants and soil parameters in the two growth cycles.

Regional Alterations in Purkinje Cell Density in Patients with Autism

PubMed Central

Skefos, Jerry; Cummings, Christopher; Enzer, Katelyn; Holiday, Jarrod; Weed, Katrina; Levy, Ezra; Yuce, Tarik; Kemper, Thomas; Bauman, Margaret

2014-01-01

Neuropathological studies, using a variety of techniques, have reported a decrease in Purkinje cell (PC) density in the cerebellum in autism. We have used a systematic sampling technique that significantly reduces experimenter bias and variance to estimate PC densities in the postmortem brains of eight clinically well-documented individuals with autism, and eight age- and gender-matched controls. Four cerebellar regions were analyzed: a sensorimotor area comprised of hemispheric lobules IV–VI, crus I & II of the posterior lobe, and lobule X of the flocculonodular lobe. Overall PC density was thus estimated using data from all three cerebellar lobes and was found to be lower in the cases with autism as compared to controls, an effect that was most prominent in crus I and II (p<0.05). Lobule X demonstrated a trend towards lower PC density in only the males with autism (p = 0.05). Brain weight, a correlate of tissue volume, was found to significantly contribute to the lower lobule X PC density observed in males with autism, but not to the finding of lower PC density in crus I & II. Therefore, lower crus I & II PC density in autism is more likely due to a lower number of PCs. The PC density in lobule X was found to correlate with the ADI-R measure of the patient's use of social eye contact (R2 = −0.75, p = 0.012). These findings support the hypothesis that abnormal PC density may contribute to selected clinical features of the autism phenotype. PMID:24586223

Reverse osmosis water purification system

NASA Technical Reports Server (NTRS)

Ahlstrom, H. G.; Hames, P. S.; Menninger, F. J.

1986-01-01

A reverse osmosis water purification system, which uses a programmable controller (PC) as the control system, was designed and built to maintain the cleanliness and level of water for various systems of a 64-m antenna. The installation operates with other equipment of the antenna at the Goldstone Deep Space Communication Complex. The reverse osmosis system was designed to be fully automatic; with the PC, many complex sequential and timed logic networks were easily implemented and are modified. The PC monitors water levels, pressures, flows, control panel requests, and set points on analog meters; with this information various processes are initiated, monitored, modified, halted, or eliminated as required by the equipment being supplied pure water.

Observed Faraday Effects in Damped Lyα Absorbers and Lyman Limit Systems: The Magnetized Environment of Galactic Building Blocks at Redshift = 2

NASA Astrophysics Data System (ADS)

Farnes, J. S.; Rudnick, L.; Gaensler, B. M.; Haverkorn, M.; O'Sullivan, S. P.; Curran, S. J.

2017-06-01

Protogalactic environments are typically identified using quasar absorption lines and can manifest as Damped Lyman-alpha Absorbers (DLAs) and Lyman Limit Systems (LLSs). We use radio observations of Faraday effects to test whether these galactic building blocks host a magnetized medium, by combining DLA and LLS detections with 1.4 GHz polarization data from the NRAO VLA Sky Survey (NVSS). We obtain a control, a DLA, and an LLS sample consisting of 114, 19, and 27 lines of sight, respectively. Using a Bayesian framework and weakly informative priors, we are unable to detect either coherent or random magnetic fields in DLAs: the regular coherent fields must be ≤slant 2.8 μG, and the lack of depolarization suggests the weakly magnetized gas in DLAs is non-turbulent and quiescent. However, we find a mild suggestive indication that LLSs have coherent magnetic fields, with a 71.5% probability that LLSs have higher | {RM}| than a control, although this is sensitive to the redshift distribution. We also find a strong indication that LLSs host random magnetic fields, with a 95.5% probability that LLS lines of sight have lower polarized fractions than a control. The regular coherent fields within the LLSs must be ≤slant 2.4 μG, and the magnetized gas must be highly turbulent with a typical turbulent length scale on the order of ≈5-20 pc. Our results are consistent with the standard dynamo paradigm, whereby magnetism in protogalaxies increases in coherence over cosmic time, and with a hierarchical galaxy formation scenario, with the DLAs and LLSs exploring different stages of magnetic field evolution in galaxies.

Source field effects in the auroral zone: Evidence from the Slave craton (NW Canada)

NASA Astrophysics Data System (ADS)

Lezaeta, Pamela; Chave, Alan; Jones, Alan G.; Evans, Rob

2007-09-01

We present an investigation of source field effects on the magnetic fields from multiple long period magnetotelluric (MT) data collected on the floors of lakes throughout the Slave craton (NW Canada) from 1998 to 2000. Monthly and daily power spectra of the magnetic fields suggest a dynamic and seasonally varying source, with atypical geomagnetic activity in year 2000. Bounded influence MT and GDS responses were obtained for periods ranging between 80 and 25,000 s over selected monthly time segments. The responses at periods over 4000 s vary, suggesting source field effects. A frequency domain principal component (PC) method was applied to the array to investigate the spatial form of the source field variations. The PC analysis was tested with synthetic data from a regional 3D model with a uniform external source to study the sensitivity of the eigenvectors to conductivity structure, demonstrating a negligible influence with increasing penetration depth. We conclude that magnetic fields at periods near one half day are subject to a 1D polarized source of relatively homogeneous morphology over the survey area during any month recorded, except for the summer month of July 2000 that had particularly high geomagnetic activity. In general, the source space approaches two polarizations at periods below one half day, with the dominant NS component seen quasi-homogeneous over the survey area at periods over 1000 s.

Chronic elevation of phosphocholine containing lipids in mice exposed to Gulf War agents pyridostigmine bromide and permethrin.

PubMed

Abdullah, Laila; Evans, James E; Montague, Hannah; Reed, Jon M; Moser, Ann; Crynen, Gogce; Gonzalez, Ariel; Zakirova, Zuchra; Ross, Ivan; Mullan, Chris; Mullan, Michael; Ait-Ghezala, Ghania; Crawford, Fiona

2013-01-01

For two decades, 25% of the veterans who served in the 1991 Gulf War (GW) have been living with Gulf War Illness (GWI), a chronic multisymptom illness. Evidence suggests that brain structures involved in cognitive function may be affected in GWI. Gulf War agents such as the acetylcholinesterase (AChE) inhibitor pyridostigmine bromide (PB) and the pesticide permethrin (PER) are considered key etiogenic factors in GWI. We therefore developed a mouse model of GW agent exposure by co-administering PB and PER and showed that this model exhibits cognitive impairment and anxiety, and increased astrogliosis at chronic post-exposure time-points. Since GW agents inhibit AChE, we hypothesized that PB+PER exposure will modulate phosphatidylcholine (PC) and sphingomyelin (SM), which are reservoirs of phosphocholine required for endogenous ACh synthesis. Lipidomic analyses showed that PC and SM were elevated in the brains of exposed compared to control mice. Brain ether PC (ePC) species were increased but lyso-platelet activating factors (lyso-PAF) that are products of ePC were decreased in exposed animals compared to controls. Catalase expression (a marker for peroxisomes) was increased in GW agent exposed mice compared to controls. Ether PC and lyso-PAF modulation was also evident in the plasma of GW agent exposed mice compared to controls. These studies suggest peroxisomal and lysosomal dysfunction in the brain at a chronic post-exposure timepoint following GW agent exposure. Our studies provide a new direction for GWI research, which will be useful for developing suitable therapies for treating GWI. © 2013 Elsevier Inc. All rights reserved.

Association of single nucleotide polymorphisms in pro-inflammatory cytokine and toll-like receptor genes with pediatric hematogenous osteomyelitis.

PubMed

Osman, A E; Mubasher, M; ElSheikh, N E; AlHarthi, H; AlZahrani, M S; Ahmed, N; ElGhazali, G; Bradley, B A; Fadil, A-S A

2016-05-23

Hematogenous osteomyelitis (HO) is a bone infection wherein bacteria penetrate to the bone through the blood stream. Several single nucleotide polymorphisms (SNPs) have been associated with susceptibility to infectious diseases. In this study, we investigated the contribution of SNPs in interleukin (IL)-1B1 (rs16944), IL1A (rs1800587), IL1B (rs1143634), toll-like receptor (TLR)-2 (rs3804099), TLR4 (rs4986790), TLR4 (rs4986791), IL1R (rs2234650), tumor necrosis factor (TNF)-α (rs1800629), TNF (rs361525), and IL1RN (rs315952) towards the development of HO in Saudi patients and compared to healthy controls. Fifty-two patients diagnosed with HO and 103 healthy individuals were genotyped. The frequencies of genotypes GG (rs16944) and AA (rs16944) were lower and higher in patients [odds ratio (OR) = 0.34, Pc = 0.05] and controls (OR = 1.33, Pc = 0.05), respectively, suggesting that SNPs at this locus could alter HO susceptibility. In addition, the patients and controls exhibited lower and higher frequencies of the alleles G (rs16944) (OR = 0.43, Pc = 0.007) and A (rs16944) (OR = 2.32, Pc = 0.007), respectively. The expression of alleles C (rs3804099) and T (rs3804099) were higher in patients (OR = 2.05, Pc = 0.04) and controls (OR = 0.49, Pc = 0.04), respectively. In conclusion, SNPs at rs16944 and rs3804099 were found to be associated with HO in the Saudi population.

A PC-Based Controller for Dextrous Arms

NASA Technical Reports Server (NTRS)

Fiorini, Paolo; Seraji, Homayoun; Long, Mark

1996-01-01

This paper describes the architecture and performance of a PC-based controller for 7-DOF dextrous manipulators. The computing platform is a 486-based personal computer equipped with a bus extender to access the robot Multibus controller, together with a single board computer as the graphical engine, and with a parallel I/O board to interface with a force-torque sensor mounted on the manipulator wrist.

Internal high-reflectivity omni-directional reflectors

NASA Astrophysics Data System (ADS)

Xi, J.-Q.; Ojha, Manas; Plawsky, J. L.; Gill, W. N.; Kim, Jong Kyu; Schubert, E. F.

2005-07-01

An internal high-reflectivity omni-directional reflector (ODR) for the visible spectrum is realized by the combination of total internal reflection using a low-refractive-index (low-n) material and reflection from a one-dimensional photonic crystal (1D PC). The low-n layer limits the range of angles in the 1D PC to values below the Brewster angle, thereby enabling high reflectivity and omni-directionality. This ODR is demonstrated using GaP as ambient, nanoporous SiO2 with a very low refractive index (n=1.10), and a four-pair TiO2/SiO2 multilayer stack. The results indicate a two orders of magnitude lower angle-integrated transverse-electric-transverse-magnetic polarization averaged mirror loss of the ODR compared with conventional distributed Bragg reflectors and metal reflectors. This indicates the high potential of the internal ODRs for optoelectronic semiconductor devices, e.g., light-emitting diodes.

SWAG: Survey of Water and Ammonia in the Galactic Center

NASA Astrophysics Data System (ADS)

Ott, Jürgen; Meier, David S.; Krieger, Nico; Rickert, Matthew

2017-01-01

SWAG (``Survey of Water and Ammonia in the Galactic Center'') is a multi-line interferometric survey toward the Center of the Milky Way conducted with the Australia Telescope Compact Array. The survey region spans the entire ~400 pc Central Molecular Zone and comprises ~42 spectral lines at pc spatial and sub-km/s spectral resolution. In addition, we deeply map continuum intensity, spectral index, and polarization at the frequencies where synchrotron, free-free, and thermal dust sources emit. The observed spectral lines include many transitions of ammonia, which we use to construct maps of molecular gas temperature, opacity and gas formation temperature (see poster by Nico Krieger et al., this volume). Water masers pinpoint the sites of active star formation and other lines are good tracers for density, radiation field, shocks, and ionization. This extremely rich survey forms a perfect basis to construct maps of the physical parameters of the gas in this extreme environment.

[Studies of immunomodulation caused by selenium-enriched phycocyanin].

PubMed

Egorova, E A; Gmoshinskiĭ, I V; Zorin, S N; Mazo, V K

2006-01-01

An influense was studied in rats of selenium enriched phycocyanin (Se-PC) from food microalgae Spirulina on anaphylactic reaction severity and circulating antibody response against model allergen--hen's egg white ovalbumin. Se-PC was introduced into diet in form of protein isolate precipitated with ammonia sulphate. Se-PC dosage made up to 450 mcg per rat daily that corresponded to 5 mcg of selenium. There were no differences revealed between experimental and control group that received standard diet in severity of anaphylactic reaction. Nevertheless rats receiving Se-PC demonstrated significantly increased specific IgG response. The probable immunomodulating properties of Se-PC included into food are discussed.

77 FR 4375 - Submission for OMB Review; Request for Comments

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-27

... collection OMB Control No. 0420-0510: Health History Form (PC-1789) and the Report of Medical Examination... History Form (PC 1789). OMB Control Number: 0420-0510. Type of Information Collection: Revision of a... Health History Form is used to document the medical history of each individual Applicant. It is a self...

Levels of plasma selenium and urinary total arsenic interact to affect the risk for prostate cancer.

PubMed

Hsueh, Yu-Mei; Su, Chien-Tien; Shiue, Horng-Sheng; Chen, Wei-Jen; Pu, Yeong-Shiau; Lin, Ying-Chin; Tsai, Cheng-Shiuan; Huang, Chao-Yuan

2017-09-01

This study investigated whether plasma selenium levels modified the risk for prostate cancer (PC) related to arsenic exposure. We conducted a case-control study that included 318 PC patients and 318 age-matched, healthy control subjects. Urinary arsenic profiles were examined using HPLC-HG-AAS and plasma selenium levels were measured by ICP-MS. We found that plasma selenium levels displayed a significant dose-dependent inverse association with PC. The odds ratio (OR) and 95% confidence interval (CI) for PC was 0.07 (0.04-0.13) among participants with a plasma selenium level >28.06 μg/dL vs. ≤19.13 μg/dL. A multivariate analysis showed that participants with a urinary total arsenic concentration >29.28 μg/L had a significantly higher OR (1.75, 1.06-2.89) for PC than participants with ≤29.89 μg/L. The combined presence of a low plasma selenium level and a high urinary total arsenic concentration exponentially increased the OR for PC, and additively interacted with PSA at levels ≥20 ng/mL. This is the first epidemiological study to examine the combined effects of plasma selenium and urinary total arsenic levels on the OR for PC. Our data suggest a low plasma selenium level coupled with a high urinary total arsenic concentration creates a significant risk for aggressive PC. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rotation measure synthesis at the 2 m wavelength of the FAN region: unveiling screens and bubbles

NASA Astrophysics Data System (ADS)

Iacobelli, M.; Haverkorn, M.; Katgert, P.

2013-01-01

Context. Rotation measure synthesis of the Westerbork Synthesis Radio Telescope (WSRT) observations at λ ~ 2 m of the FAN region at l = 137°, b = +7° shows the morphology of structures in the ionized interstellar medium. Aims: We interpret the diffuse polarized synchrotron emission in terms of coherent structures in the interstellar medium and the properties of the interstellar magnetic field. Methods: We performed statistical analysis of the polarization data cube obtained through rotation measure synthesis. For the first time, cross-correlation is applied to identify and characterize polarized structures in Faraday depth space. Complementary information about the medium are derived from Hα emission, properties of nearby pulsars, and optical polarized starlight measurements. Results: We find an overall asymmetric Faraday dispersion function in a Faraday depth range of [-13, +5] rad m-2, which is peaked around -1 rad m-2. Three morphological patterns are recognized, showing structures on scales from degrees down to the beam size. The first structure is a nearby synchrotron emission component with low Faraday depth, filling the entire field of view. The second pattern is a circular polarization structure with enhanced (negative) Faraday depth, which has the same morphology as a low-emission region within the third component. This third component is interpreted as the background in which the circular structure is embedded. At low Faraday depth values, a low gradient across the imaged field is detected, almost aligned with the Galactic plane. Power spectra of polarized structures in Faraday depth space provide evidence of turbulence. Conclusions: A sign reversal in Faraday depth from the nearby component to the circular component indicates a reversal of the magnetic field component along the line of sight, from towards the observer and nearby to away from the observer at large distances. The distance to the nearby, extended component is estimated as ≲100 pc, which suggests that this structure corresponds to the Local Bubble wall. For the circular component, various physical interpretations are discussed. The most likely explanation is that the circular component seems to be the presence of a nearby (~200 pc away) relic Strömgren sphere, associated with an old unidentified white dwarf star and expanding in a low-density environment. Faraday rotation datacubes are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/549/A56

Phospholipid order in gel- and fluid-phase cell-size liposomes measured by digitized video fluorescence polarization microscopy.

PubMed Central

Florine-Casteel, K

1990-01-01

Low-light digitized video fluorescence microscopy has been utilized to measure the steady-state polarized fluorescence from the membrane probe diphenylhexatriene (DPH) and its cationic and phosphatidylcholine derivatives 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH) and 2-[3-(diphenylhexatrienyl)propanoyl]-3-palmitoyl-L-alpha-phosphati dylcholine (DPH-PC), respectively, in cell-size (10-70 microns) unilamellar vesicles composed of gel-or fluid-phase phospholipid. Using an inverted microscope with epi-illumination optics and an intensified silicon intensified target camera interfaced to a minicomputer, fluorescence images of single vesicles were obtained at emission polarizer orientations of 0 degrees, 45 degrees, 90 degrees, and 135 degrees relative to the excitation light polarization direction. Fluorescence intensity ratios F90 degrees/F0 degrees (= F perpendicular/F parallel) and F135 degrees/F45 degrees were calculated on a pixel-by-pixel basis from digitized image pairs. Theoretical expressions were derived for collected polarized fluorescence as a function of position on the membrane surface as well as the degree of lipid order, in terms of the fluorophore's maximum angular motional freedom in the bilayer (identical to theta max), using a modification of the method of D. Axelrod (1979. Biophys. J. 26:557-574) together with the "wobbling-in-a-cone" model of probe rotational diffusion. Comparison of experimental polarization ratios with theoretical ratios yielded the following results. In gel-phase dipalmitoyl-phosphatidylcholine, the data for all three probes correspond to a model in which the cone angle theta max = 17 +/- 2 degrees and there exists a collective tilt of the phospholipid acyl chains of 30 degrees relative to the bilayer normal. In addition, approximately 5% of DPH and TMA-DPH molecules are aligned parallel to the plane of the bilayer. In fluid-phase palmitoyloleoyl-phosphatidylcholine, the data are well fit by models in which theta max = 60 +/- 2 degrees for DPH and DPH-PC and 32 +/- 4 degrees for TMA-DPH, with approximately 20% of DPH molecules and 10% of TMA-DPH molecules aligned parallel to the bilayer plane, and a net phospholipid tilt at or near the headgroup region of approximately 30 degrees. The results demonstrate that lipid order can be measured with a spatial resolution of approximately 1 micron2 in cell-size vesicles even with high aperture observation through a microscope. Images FIGURE 4 FIGURE 7 FIGURE 10 PMID:2393705

The polycystins are modulated by cellular oxygen-sensing pathways and regulate mitochondrial function

PubMed Central

Padovano, Valeria; Kuo, Ivana Y.; Stavola, Lindsey K.; Aerni, Hans R.; Flaherty, Benjamin J.; Chapin, Hannah C.; Ma, Ming; Somlo, Stefan; Boletta, Alessandra; Ehrlich, Barbara E.; Rinehart, Jesse; Caplan, Michael J.

2017-01-01

Autosomal dominant polycystic kidney disease is caused by mutations in the genes encoding polycystin-1 (PC1) and polycystin-2 (PC2), which form an ion channel complex that may mediate ciliary sensory processes and regulate endoplasmic reticulum (ER) Ca2+ release. Loss of PC1 expression profoundly alters cellular energy metabolism. The mechanisms that control the trafficking of PC1 and PC2, as well as their broader physiological roles, are poorly understood. We found that O2 levels regulate the subcellular localization and channel activity of the polycystin complex through its interaction with the O2-sensing prolyl hydroxylase domain containing protein EGLN3 (or PHD3), which hydroxylates PC1. Moreover, cells lacking PC1 expression use less O2 and show less mitochondrial Ca2+ uptake in response to bradykinin-induced ER Ca2+ release, indicating that PC1 can modulate mitochondrial function. These data suggest a novel role for the polycystins in sensing and responding to cellular O2 levels. PMID:27881662

KSC-99pc05

NASA Image and Video Library

1999-01-03

KENNEDY SPACE CENTER, FLA. -- Amid clouds of exhaust, a Boeing Delta II expendable launch vehicle with NASA's Mars Polar Lander clears Launch Complex 17B, Cape Canaveral Air Station, after launch at 3:21:10 p.m. EST. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south polar cap, which consists of carbon dioxide ice. The lander will study the polar water cycle, frosts, water vapor, condensates and dust in the Martian atmosphere. It is equipped with a robotic arm to dig beneath the layered terrain at the polar cap. In addition, Deep Space 2 microprobes, developed by NASA's New Millennium Program, are installed on the lander's cruise stage. After crashing into the planet's surface, they will conduct two days of soil and water experiments up to 1 meter (3 feet) below the Martian surface, testing new technologies for future planetary descent probes. The lander is the second spacecraft to be launched in a pair of Mars Surveyor '98 missions. The first is the Mars Climate Orbiter, which was launched aboard a Delta II rocket from Launch Complex 17A on Dec. 11, 1998.

KSC-99pc04

NASA Image and Video Library

1999-01-03

KENNEDY SPACE CENTER, FLA. -- Amid clouds of exhaust and into a gray-clouded sky , a Boeing Delta II expendable launch vehicle lifts off with NASA's Mars Polar Lander at 3:21:10 p.m. EST from Launch Complex 17B, Cape Canaveral Air Station. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south polar cap, which consists of carbon dioxide ice. The lander will study the polar water cycle, frosts, water vapor, condensates and dust in the Martian atmosphere. It is equipped with a robotic arm to dig beneath the layered terrain at the polar cap. In addition, Deep Space 2 microprobes, developed by NASA's New Millennium Program, are installed on the lander's cruise stage. After crashing into the planet's surface, they will conduct two days of soil and water experiments up to 1 meter (3 feet) below the Martian surface, testing new technologies for future planetary descent probes. The lander is the second spacecraft to be launched in a pair of Mars Surveyor '98 missions. The first is the Mars Climate Orbiter, which was launched aboard a Delta II rocket from Launch Complex 17A on Dec. 11, 1998.

KSC-99pc06

NASA Image and Video Library

1999-01-03

KENNEDY SPACE CENTER, FLA. -- Silhouetted against the gray sky, a Boeing Delta II expendable launch vehicle with NASA's Mars Polar Lander lifts off from Launch Complex 17B, Cape Canaveral Air Station, at 3:21:10 p.m. EST. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south polar cap, which consists of carbon dioxide ice. The lander will study the polar water cycle, frosts, water vapor, condensates and dust in the Martian atmosphere. It is equipped with a robotic arm to dig beneath the layered terrain at the polar cap. In addition, Deep Space 2 microprobes, developed by NASA's New Millennium Program, are installed on the lander's cruise stage. After crashing into the planet's surface, they will conduct two days of soil and water experiments up to 1 meter (3 feet) below the Martian surface, testing new technologies for future planetary descent probes. The lander is the second spacecraft to be launched in a pair of Mars Surveyor '98 missions. The first is the Mars Climate Orbiter, which was launched aboard a Delta II rocket from Launch Complex 17A on Dec. 11, 1998.

KSC-99pc03

NASA Image and Video Library

1999-01-03

KENNEDY SPACE CENTER, FLA. -- A Boeing Delta II expendable launch vehicle lifts off with NASA's Mars Polar Lander into a cloud-covered sky at 3:21:10 p.m. EST from Launch Complex 17B, Cape Canaveral Air Station. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south polar cap, which consists of carbon dioxide ice. The lander will study the polar water cycle, frosts, water vapor, condensates and dust in the Martian atmosphere. It is equipped with a robotic arm to dig beneath the layered terrain at the polar cap. In addition, Deep Space 2 microprobes, developed by NASA's New Millennium Program, are installed on the lander's cruise stage. After crashing into the planet's surface, they will conduct two days of soil and water experiments up to 1 meter (3 feet) below the Martian surface, testing new technologies for future planetary descent probes. The lander is the second spacecraft to be launched in a pair of Mars Surveyor '98 missions. The first is the Mars Climate Orbiter, which was launched aboard a Delta II rocket from Launch Complex 17A on Dec. 11, 1998.

Cluster observations of band-limited Pc 1 waves associated with streaming H+ and O+ ions in the high-altitude plasma mantle

NASA Astrophysics Data System (ADS)

Engebretson, M. J.; Kahlstorf, C. R. G.; Murr, D. L.; Posch, J. L.; Keiling, A.; Lavraud, B.; Rème, H.; Lessard, M. R.; Kim, E.-H.; Johnson, J. R.; Dombeck, J.; Grison, B.; Robert, P.; Glassmeier, K.-H.; Décréau, P. M. E.

2012-10-01

Bursts of band-limited Pc 1 waves (0.2 to ˜1.0 Hz) with normalized frequency f/fH+ ˜ 0.5 have been observed by the Cluster spacecraft during many passes through the high-latitude plasma mantle. These transverse, left-hand polarized waves are associated with regions of H+ and O+ ions streaming away from Earth along magnetic field lines at the same velocity (˜140 km/s). Waves were observed only when H+ fluxes increased by factors of 10-1000 and energies of both ion species increased by factors of up to 10. We present two satellite-ground conjunctions to demonstrate the high latitude localization of these waves and their ability to reach the polar ionosphere and two extended examples of waves and associated ion distribution functions near the southern dusk flank magnetopause. We also present the results of a search for all such events during Cluster's 2002 and 2003 passages through the magnetotail, with orbital precession covering dawn to dusk on Earth's night side (June through December). A total of 46 events (band-limited Pc 1-2 waves accompanied by a sustained population of streaming H+ and O+ ions, separated by at least 12 min) were observed on 29 days. The waves were generally associated with intervals of southward IMF Bz and/or large IMF By (times of active cusp reconnection), and often but not always occurred during the main phase or early recovery phase of magnetic storms. Analysis of selected events shows that the waves are associated with large H+ temperature anisotropy, and that the waves propagate opposite to the direction of the streaming ions. A wave instability analysis using the WHAMP code confirms that the generation of these waves, via the ion cyclotron instability, is basically consistent with known physics. Their extended region of wave growth is likely, however, to reach tailward significantly beyond the Cluster orbit.

The X-ray Spectrum of the North Polar Spur

NASA Technical Reports Server (NTRS)

Willingale, Richard; Hands, A. D. P.; Warwick, R. S.; Snowden, S. L.; Burrows, David N.

2003-01-01

An analysis is presented of the soft X-ray background spectrum measured by the EPIC MOS cameras on XMM-Newton in three observations targeted on the North Polar Spur (NPS). Three distinct Galactic plasma components are identified, a cool Local Hot Bubble (LHB) component, T(sub lo) approx. 0.1 keV, a cool Galactic Halo component at a similar temperature and a hotter component, T(sub hi) approx. 0.26 keV, associated with the NPS itself. Using the new data in combination with the Rosat All-Sky Survey count rates measured in the 0.1-0.4 keV band, we estimate the emission measure of the LHB material to be 0.0040-0.0052 cm(exp -6) pc, which implies an electron density of 0.008-0.011 cm(exp -3) and pressure of approx. 22000 cm(exp -3) K. The halo and NPS components lie behind at least 50% of the line-of-sight cold gas for which the total Galactic column density is in the range (2 - 8) x 10(exp 20) cm(exp -2). Modelling the X-ray emitting superbubble as a sphere at distance 210 pc, radius 140 pc and center l(sub II) = 352 deg, b(sub II) = 15 deg, the implied electron density in the NPS is approx. 0.03 cm(exp -3) with pressure approx. 150000 cm(exp -3) K. The observed spectral line complexes from OVII, OVIII, FeXVII, NeIX, NeX and MgXI provide constraints on the composition of the plasma. The hot component in the NPS is depleted in oxygen, neon and, to some extent, magnesium and iron. Assuming the effective line of sight across the halo emission is 1 kpc, the electron density in the halo is 0.007-0.011 cm(exp -3) and the pressure is approx. 16500 cm(exp -3) K, conditions very similar to those in the LHB.

Aging in Fragile X Premutation Carriers.

PubMed

Lozano, Reymundo; Saito, Naomi; Reed, Dallas; Eldeeb, Marwa; Schneider, Andrea; Hessl, David; Tassone, Flora; Beckett, Laurel; Hagerman, Randi

2016-10-01

It is now recognized that FMR1 premutation carriers (PC) are at risk to develop a range of neurological, psychiatric, and immune-mediated disorders during adulthood. There are conflicting findings regarding the incidence of hypertension, hypothyroidism, diabetes, and cancer in these patients that warrant further study. A retrospective controlled study was performed in a convenience sample of 248 controls (130 men, 118 women) and 397 FMR1 PC with and without fragile X-associated tremor ataxia syndrome (FXTAS) (176 men, 221 women); all participants were at least 45 years old (men: mean 62.4, SD 9.5; women: mean 62.8, SD 9.9; p = 0.63). Memory and cognitive assessments (Wechsler Adult Intelligence Scale (WAIS-III), Wechsler Memory Scale (WMS-III)) and molecular testing (CGG repeats and FMR1-mRNA levels) were performed. Additional data included body mass index (BMI), cholesterol levels, blood pressure, hemoglobin A1c (HbA1c) levels, and medical history. A higher percentage of PC subjects self-reported having a diagnosis of hypertension (50.0 vs. 35.0 %, p = 0.006) and thyroid problems (20.4 vs. 10.0 %, p = 0.012) than control subjects. When comparing controls versus PC with FXTAS, the association was higher for diabetes (p = 0.043); however, the effect was not significant after adjusting for demographic predictors. Blood pressure, blood glucose levels, HbA1c, and BMI values were not significantly different between the two groups. The PC with FXTAS group performed consistently lower in neuropsychological testing compared with the PC without FXTAS group, but the differences were very small for all but the WAIS full-scale IQ. Based on these findings, it appears that the risk for hypertension, thyroid problems, and diabetes may be more frequent in PC with FXTAS, which will require verification in future studies.

Retromer associates with the cytoplasmic amino-terminus of polycystin-2.

PubMed

Tilley, Frances C; Gallon, Matthew; Luo, Chong; Danson, Chris M; Zhou, Jing; Cullen, Peter J

2018-05-03

Autosomal dominant polycystic kidney disease (ADPKD) is the most common monogenic human disease, with around 12.5 million people affected worldwide. ADPKD results from mutations in either PKD1 or PKD2 , which encode the atypical G-protein coupled receptor polycystin-1 (PC1) and the transient receptor potential channel polycystin-2 (PC2) respectively. Although altered intracellular trafficking of PC1 and PC2 appear as an underlying feature of ADPKD, the mechanisms which govern vesicular transport of the polycystins through the biosynthetic and endosomal membrane networks remain to be fully elucidated. Here, we describe an interaction between PC2 and retromer, a master controller for the sorting of integral membrane proteins through the endo-lysosomal network. We show that association of PC2 with retromer occurs via a region in the PC2 cytoplasmic amino-terminal domain, independently of the retromer-binding Wiskott-Aldrich syndrome and scar homologue (WASH) complex. Based on observations that retromer preferentially interacts with a trafficking population of PC2, and that ciliary levels of PC1 are reduced upon mutation of key residues required for retromer-association in PC2, our data is consistent with the identification of PC2 as a retromer cargo protein. © 2018. Published by The Company of Biologists Ltd.

Pleiotropy between genetic markers of obesity and risk of prostate cancer

PubMed Central

Edwards, Todd L.; Giri, Ayush; Motley, Saundra; Duong, Wynne; Fowke, Jay H.

2013-01-01

Background To address inconsistent findings of obesity and prostate cancer risk, we analyzed the association between prostate cancer (PC) and genetic markers of obesity and metabolism. Methods Analyses included 176,520 single nucleotide polymorphisms (SNPs) associated with 23 metabolic traits. We examined the association between SNPs and PC in 871 cases and 906 controls, including 427 high-grade cases with Gleason ≥7. Genetic risk scores (GRSs) for body mass index (BMI) and waist-to-hip ratio (WHR) were also created by summing alleles associated with increasing BMI or WHR. Results PC was associated with 5 loci, including cyclin M2, with p-values less than 1×10−4. In addition, the WHR GRS was associated with high-grade PC versus controls (OR: 1.05; 95% CI: 1.00 – 1.11, p-value = 0.048), and high-grade PC versus low-grade PC (OR: 1.07, 95% CI 1.01 – 1.13, p-value = 0.03). None of these findings exceed the threshold for significance after correction for multiple testing. Conclusions Variants in genes known to be associated with metabolism and obesity may be associated with PC. We show evidence for pleiotropy between WHR GRS and PC grade. This finding is consistent with the function of several WHR genes, and previously described relationships with cancer traits. Impact Limitations in standard obesity measures suggest alternative characterizations of obesity may be needed to understand the role of metabolic dysregulation in PC. The underlying genetics of WHR or other Metabochip SNPs, while not statistically significant beyond multiple testing thresholds within our sample size, support the metabolic hypothesis of prostate carcinogenesis and warrant further investigation in independent samples. PMID:23810916

Carotenoid Photoprotection in Artificial Photosynthetic Antennas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kloz, Miroslav; Pillai, Smitha; Kodis, Gerdenis

A series of phthalocyanine-carotenoid dyads in which a phenylamino group links a phthalocyanine to carotenoids having 8-11 backbone double bonds were examined by visible and near-infrared femtosecond pump-probe spectroscopy combined with global fitting analysis. The series of molecules has permitted investigation of the role of carotenoids in the quenching of excited states of cyclic tetrapyrroles. The transient behavior varied dramatically with the length of the carotenoid and the solvent environment. Clear spectroscopic signatures of radical species revealed photoinduced electron transfer as the main quenching mechanism for all dyads dissolved in a polar solvent (THF), and the quenching rate was almostmore » independent of carotenoid length. However, in a nonpolar solvent (toluene), quenching rates displayed a strong dependence on the conjugation length of the carotenoid and the mechanism did not include charge separation. The lack of any rise time components of a carotenoid S 1 signature in all experiments in toluene suggests that an excitonic coupling between the carotenoid S 1 state and phthalocyanine Q state, rather than a conventional energy transfer process, is the major mechanism of quenching. A pronounced inhomogeneity of the system was observed and attributed to the presence of a phenyl-amino linker between phthalocyanine and carotenoids. On the basis of accumulated work on various caroteno-phthalocyanine dyads and triads, we have now identified three mechanisms of tetrapyrrole singlet excited state quenching by carotenoids in artificial systems: (i) Car-Pc electron transfer and recombination; (ii) 1Pc to Car S 1 energy transfer and fast internal conversion to the Car ground state; (iii) excitonic coupling between 1Pc and Car S 1 and ensuing internal conversion to the ground state of the carotenoid. The dominant mechanism depends upon the exact molecular architecture and solvent environment. These synthetic systems are providing a deeper understanding of structural and environmental effects on the interactions between carotenoids and tetrapyrroles and thereby better defining their role in controlling natural photosynthetic systems.« less

LncRNA AWPPH inhibits SMAD4 via EZH2 to regulate bladder cancer progression.

PubMed

Zhu, Feng; Zhang, Xinjun; Yu, Qinnan; Han, Guangye; Diao, Fengxia; Wu, Chunlei; Zhang, Yan

2018-06-01

This study aimed to investigate the effect and underlying mechanism of lncRNA AWPPH in bladder cancer (BC). A total of 20 Ta-T1 stage BC tissues, 20 T2-T4 stage BC tissues, and 20 normal bladder tissues, as well as human bladder epithelial cell line SV-HUC-1, human BC cell lines RT4, and T24 were obtained to detect the levels of AWPPH, enhancer of zeste homolog 2 (EZH2) and SMAD4 using RT-qPCR or Western blotting. RT4 cells were transfected with pc-AWPPH, pc-EZH2, or pc-control and T24 cells were transfected with si-AWPPH, si-EZH2, si-control, or pc-AWPPH + pc-SMAD4, respectively. Then, cell proliferation, apoptosis, autophagy, and migration, were detected using MTT assay, colony formation assay, Annexin V-FITC/PI method, Western blotting, and Transwell analysis, respectively. The relationship of AWPPH and EZH2 or SMAD4 was evaluated by RNA immunoprecipitation (RIP) assay or Chromatin immunoprecipitation (ChIP) assay. Compared with normal bladder tissues or cells, the levels of AWPPH and EZH2 were overexpressed, while SMAD4 was down-regulated in BC tissues or cells (all P < 0.01). Cell viability, colony number, and migration were significantly increased, while cell apoptosis ratio was reduced in cells with pc-AWPPH compared with cells with pc-control (all P < 0.05), meanwhile, these effects were reversed by the treatment of pc-SMAD4. Then, RIP assay revealed that AWPPH could bind to EZH2 and ChIP assay showed SMAD4 was regulated by EZH2. LncRNA AWPPH can promote cell proliferation, autophagy, and migration, as well as inhibit cell apoptosis in BC by inhibiting SMAD4 via EZH2. © 2017 Wiley Periodicals, Inc.

Focal cerebral ischemic tolerance and change in blood-brain barrier permeability after repetitive pure oxygen exposure preconditioning in a rodent model.

PubMed

Wang, Xi; Kang, Kai; Wang, Shiquan; Yao, Jianhua; Zhang, Xijing

2016-10-01

OBJECTIVE The goal of this study was to demonstrate that repetitive pure oxygen exposure preconditioning (O 2 PC) for 8 hours per day for 3 or 7 days, a practicable preconditioning for clinical use, is able to induce cerebral ischemic tolerance (IT) and further clarify the accompanying changes in the blood-brain barrier (BBB) that may be involved. METHODS A total of 68 adult male Sprague-Dawley rats and eight 1-day-old rat pups were used in this study. The adult rats were exposed to pure O 2 (38 rats) 8 hours a day for 3 or 7 days or to room air (in an identical setup) for 8 hours a day for 7 days as controls (30 rats). Arterial O 2 tension (PaO 2 ) was measured in 6 rats exposed to O 2 and 3 controls. Focal cerebral ischemia was elicited by middle cerebral artery occlusion (MCAO) in 37 rats, of which 21 had been exposed to pure O 2 for 3 or 7 days and 16 to room air for 7 days as controls. Neurological behavior was scored with the Garcia score in 15 MCAO rats, of which 10 had been exposed to pure O 2 for 3 or 7 days and 5 to room air for 7 days as controls, and cerebral infarct volumes were assessed with TTC (2,3,5-triphenyltetrazolium chloride) staining in 10 rats (5 from each group) after 7 days of exposure. Formamide-extraction method was used to detect leakage of Evans blue (EB) dye in 7 rats exposed to pure O 2 for 7 days and 7 exposed to room air for 7 days. Fluorescence microscopy was used to analyze the leaked EB in the nonischemic areas of 4 rats exposed to pure O 2 for 7 days and 4 exposed to room air for 7 days before MCAO and the brain of the rats that had not been subjected to MCAO. Astrocyte changes associated with O 2 PC were evaluated by means of fluorescence microscopy and electron microscopy in 14 rats that were exposed to the same O 2 or control conditions as the MCAO rats but without MCAO. Astrocytes were also obtained from 8 rat pups and cultured; levels of AQP4 and VEGF were detected by Western blot and ELISA in cells with and without O 2 treatment. RESULTS A significant increase in PaO 2 was seen after O 2 PC. The neurological score was significantly increased in the O 2 PC groups (10.6 ± 0.6 in the 3-day O 2 PC group, p < 0.05; 12 ± 0.84 in the 7-day O 2 PC group, p < 0.05) compared with the control group (7 ± 0.55). The ratio of cerebral infarct volume to contralateral cerebral hemisphere volume was significantly lower in the O 2 PC group than in the control group (0.204 ± 0.03 vs 0.48 ± 0.05, p < 0.05). The amount of leaked EB in the ischemic cerebral hemisphere was also lower in the O 2 -treated rats than in controls (7.53 ± 1.4 vs 11.79 ± 3.3 μg EB/g brain weight, p < 0.05). However, fluorescence microscopy showed significantly greater BBB permeability in the nonischemic areas in the O 2 PC group than in controls (p < 0.05). More red fluorescence could be observed in the nonischemic areas in both the ipsilateral and contralateral sides of the ischemic brain in the O 2 PC animals than in the nonischemic areas in the corresponding sides of the controls. Further investigation of the effect of the O 2 PC itself on the BBB of rats that were not subjected to MCAO showed that there was no EB leakage in the brain parenchyma in the rats exposed to room air, but some red fluorescence patches were noticed in the normal brain from the rats in the O 2 PC group. Astrocytes, including those from areas around the BBB, were activated in the O 2 PC group. Levels of both aquaporin 4 (AQP4) and vascular endothelial growth factor (VEGF) were significantly increased in cultured astrocytes after O 2 PC. CONCLUSIONS These findings suggest that O 2 PC is able to induce IT, which makes it a strong candidate for clinical use. Moreover, O 2 PC can also promote BBB opening, which may contribute to the induction of IT as well as representing a possible strategy for promoting drug transportation into the CNS. Activated astrocytes are likely to be involved in these processes through astrocyte-derived factors, such as AQP4 and VEGF.

HAWC+/SOFIA observations of Rho Oph A: far-infrared polarization spectrum

NASA Astrophysics Data System (ADS)

Santos, Fabio; Dowell, Charles D.; Houde, Martin; Looney, Leslie; Lopez-Rodriguez, Enrique; Novak, Giles; Ward-Thompson, Derek; HAWC+ Science Team

2018-01-01

In this work, we present preliminary results from the HAWC+ far-infrared polarimeter that operates on the SOFIA airborne observatory. The densest portions of the Rho Ophiuchi molecular complex, known as Rho Oph A, have been mapped using HAWC+ bands C (89 microns) and D (155 microns). Rho Oph A is a well known nearby star forming region. At the target's distance of approximately 130 pc, our observations provide excellent spatial resolution (~5 mpc in band C).The magnetic field map suggests a compressed and distorted field morphology around Oph S1, a massive B3 star that is the main heat source of Rho Oph A. We compute the ratio p(D)/p(C), where p(C) and p(D) are the polarization degree maps at bands C and D, respectively. This ratio estimates the slope of the polarization spectrum in the far-infrared. Although the slope is predicted to be positive by dust grain models, previous observations of other molecular clouds have revealed that negative slopes are common. In Rho Oph A, we find that there is a smooth gradient of p(D)/p(C) across the mapped field. The change in p(D)/p(C) is well correlated with the integrated NH3 (1,1) emission. A positive slope dominates the lower density and well illuminated portions of the cloud, whereas a transition to a negative slope is observed at the denser and less evenly illuminated cloud core.We interpret the positive to negative slope transition as being consistent with the radiative torques (RATs) grain alignment theory. For the sight lines of higher column density, polarized emission from the warmer outer cloud layers is added to emission from the colder inner well-shielded layers lying along the same line-of-sight. Given that the outer layers receive more radiation from Oph S1, their grain alignment efficiency is expected to be higher according to RATs. The combination of warmer, well aligned grains with cooler, poorly aligned grains is what causes the negative slope. This effect is not present in the sight lines of lower column density, due to the much lower extinction.

Research Laboratory of Electronics Progress Report Number 134

DTIC Science & Technology

1991-12-31

Optical Pulse Compression," J. Opt. Soc. Am. 8 4:1404 (1987); C.H. Bito Cruz, P.C. Becker, R.L Fork, and C.V. Shank, ’Phase Correction of Femtosecond...sented at the IEEE Lasers and Electro-Optical the inputs to the external cavity, and coherence of Society ( LEOS ) Annual Conference, San Jose, the output...with second- image (8 GHz frequency) in which complex polar- epoch measurements of the dMe stars AD Leo , EV ization structure is evident. We will use

Reduced Symmetry and Analogy to Chirality in Periodic Dielectric Media

NASA Astrophysics Data System (ADS)

Giden, I. H.; Turduev, M.; Kurt, H.

2014-10-01

Much attention has been paid to photonic applications based on periodic media. Meanwhile, quasi-periodic and disordered media have extended the research domain and provided additional novelties for manipulating and controlling light propagation. This review article attempts to highlight the benefits of symmetry reduction in highly symmetric periodic photonic media, and applies the concept of chirality to all-dielectric materials arranged in special orders. Two-dimensional periodic structures known as photonic crystals (PCs) are highly symmetric in terms of structural patterns, due to the lattice types and shape of the elements occupying the PC unit-cell. We propose the idea of intentionally introducing reduced-symmetry, to search for anomalous optical characteristics so that these types of PCs can be used in the design of novel optical devices. Breaking either translational or rotational symmetries of PCs provides enhanced and additional optical characteristics such as creation of a complete photonic bandgap, wavelength demultiplexing, super-collimation, tilted self-collimation, and beam deflecting/routing properties. Utilizing these characteristics allows the design of several types of photonic devices such as polarization-independent waveguides, wavelength demultiplexers, beam deflectors, and routers. Moreover, reducing the symmetry in the PC unit-cell scale produces a novel feature in all-dielectric PCs that is known as chirality. On the basis of above considerations, it is expected that low-symmetric PCs can be considered as a potential structure in photonic device applications, due to the rich inherent optical properties, providing broadband operation, and being free of absorption losses.

First Near-infrared Imaging Polarimetry of Young Stellar Objects in the Circinus Molecular Cloud

NASA Astrophysics Data System (ADS)

Kwon, Jungmi; Nakagawa, Takao; Tamura, Motohide; Hough, James H.; Choi, Minho; Kandori, Ryo; Nagata, Tetsuya; Kang, Miju

2018-02-01

We present the results of near-infrared (NIR) linear imaging polarimetry in the J, H, and K s bands of the low-mass star cluster-forming region in the Circinus Molecular Cloud Complex. Using aperture polarimetry of point-like sources, positive detection of 314, 421, and 164 sources in the J, H, and K s bands, respectively, was determined from among 749 sources whose photometric magnitudes were measured. For the source classification of the 133 point-like sources whose polarization could be measured in all 3 bands, a color–color diagram was used. While most of the NIR polarizations of point-like sources are well-aligned and can be explained by dichroic polarization produced by aligned interstellar dust grains in the cloud, 123 highly polarized sources have also been identified with some criteria. The projected direction on the sky of the magnetic field in the Cir-MMS region is indicated by the mean polarization position angles (70°) of the point-like sources in the observed region, corresponding to approximately 1.6× 1.6 pc2. In addition, the magnetic field direction is compared with the outflow orientations associated with Infrared Astronomy Satellite sources, in which two sources were found to be aligned with each other and one source was not. We also show prominent polarization nebulosities over the Cir-MMS region for the first time. Our polarization data have revealed one clear infrared reflection nebula (IRN) and several candidate IRNe in the Cir-MMS field. In addition, the illuminating sources of the IRNe are identified with near- and mid-infrared sources.

Transcutaneous Electrical Stimulation Increased Nitric Oxide-Cyclic GMP Release Biocaptured Over Skin Surface of Pericardium Meridian and Acupuncture Points in Humans

PubMed Central

Ma, Sheng-Xing; Mayer, Emeran; Lee, Paul; Li, Xi-yan; Gao, Ellen Z.

2015-01-01

Objectives The purpose of this study was to consecutively capture and quantify nitric oxide (NO) and cGMP, the second messenger of NO, over the skin surface of acupuncture points (acupoints), meridian line without acupoint, and non-meridian control regions of the Pericardium meridian (PC) in humans, and investigate their response to transcutaneous electrical nerve stimulation (TENS). Design, setting, and main outcome measures Adhesive biocapture tubes were attached to the skin surface along PC regions and injected with 2-Phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl solution, an NO-scavenging compound, contacting the skin surface for 20 minutes each during 4 consecutive biocapture intervals. TENS (1.0 mA, 6 Hz, 1.0 msec duration) was applied over acupoints PC 8 and PC 3 during the 2nd biocapture for 20 min. Total nitrite and nitrate (NOx-), the stable metabolic products of NO, and cGMP in biocaptured samples were quantified using chemiluminescence and ELISA. Results NOx- levels in the 1st biocapture over PC regions are almost two fold higher compared to subsequent biocaptures and are higher over PC acupoints versus non-meridian control region. Following TENS, NOx- concentrations over PC regions were significantly increased, and cGMP is predominantly released from the skin surface of PC acupoints. Conclusions TENS induces elevations of NO-cGMP concentrations over local skin region with a high level at acupoints. The enhanced signal molecules improve local circulation, which contributes to beneficial effects of the therapy. PMID:26369251

Eicosapentaenoic acid-enriched phosphatidylcholine isolated from Cucumaria frondosa exhibits anti-hyperglycemic effects via activating phosphoinositide 3-kinase/protein kinase B signal pathway.

PubMed

Hu, Shiwei; Xu, Leilei; Shi, Di; Wang, Jingfeng; Wang, Yuming; Lou, Qiaoming; Xue, Changhu

2014-04-01

Eicosapentaenoic acid-enriched phosphatidylcholine was isolated from the sea cucumber Cucumaria frondosa (Cucumaria-PC) and its effects on streptozotocin (STZ)-induced hyperglycemic rats were investigated. Male Sprague-Dawley rats were randomly divided into normal control, model control (STZ), low- and high-dose Cucumaria-PC groups (STZ + Cucumaria-PC at 25 and 75 mg/Kg·b·wt, intragastrically, respectively). Blood glucose, insulin, glycogen in liver and gastrocnemius were determined over 60 days. Insulin signaling in the rats' gastrocnemius was determined by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting. The results showed that Cucumaria-PC significantly decreased blood glucose level, increased insulin secretion and glycogen synthesis in diabetic rats. RT-PCR analysis revealed that Cucumaria-PC significantly promoted the expressions of glycometabolism-related genes of insulin receptor (IR), insulin receptor substrate-1 (IRS-1), phosphoinositide 3-kinase (PI3K), protein kinase B (PKB), and glucose transporter 4 (GLUT4) in gastrocnemius. Western blotting assay demonstrated that Cucumaria-PC remarkably enhanced the proteins abundance of IR-β, PI3K, PKB, GLUT4, as well as phosphorylation of Tyr-IR-β, p85-PI3K, Ser473-PKB (P < 0.05 and P < 0.01). These findings suggested that Cucumaria-PC exhibited significant anti-hyperglycemic activities through up-regulating PI3K/PKB signal pathway mediated by insulin. Nutritional supplementation with Cucumaria-PC, if validated for human studies, may offer an adjunctive therapy for diabetes mellitus. Copyright © 2013 The Society for Biotechnology, Japan. All rights reserved.

The UCP2 -866G/A, Ala55Val and UCP3 -55C/T polymorphisms are associated with premature coronary artery disease and cardiovascular risk factors in Mexican population.

PubMed

Gamboa, Ricardo; Huesca-Gómez, Claudia; López-Pérez, Vanessa; Posadas-Sánchez, Rosalinda; Cardoso-Saldaña, Guillermo; Medina-Urrutia, Aida; Juárez-Rojas, Juan Gabriel; Soto, María Elena; Posadas-Romero, Carlos; Vargas-Alarcón, Gilberto

2018-05-21

We examined the role of UCP gene polymorphisms as susceptibility markers for premature coronary artery disease (pCAD). The UCP2 Ala55Val (C/T rs660339), UCP2 -866G/A (rs659366), and UCP3 -55C/T (rs1800849) polymorphisms were genotyped in 948 patients with pCAD, and 763 controls. The distribution of the UCP2 A55V (C/T rs660339) and UCP3 -55 (rs1800849) was similar in patients and controls. However, under a recessive model, the UCP2 -866 (rs659366) A allele was associated with increased risk of developing pCAD (OR = 1.43, Pc = 0.003). On the other hand, patients with pCAD and UCP2 A55V (rs660339) TT showed high levels of visceral abdominal fat (VAF) (Pc = 0.002), low levels of subcutaneous abdominal fat (SAF) (Pc = 0.001) and high VAT/SAT ratio (Pc < 0.001). Also, patients with UCP2 -866 (rs659366) AA showed increased levels of VAF (Pc = 0.003), low levels of SAF (Pc = 0.001) and a high VAT/SAT ratio (Pc = 0.002), whereas patients with the UCP3 -55 (rs1800849) TT presented high levels of VAF (Pc = 0.002). The results suggest the association of the UCP2 -866 (rs659366) polymorphism with risk of developing pCAD. Some polymorphisms were associated with abdominal fat levels and cardiovascular risk factors.

Effect of lysophosphatidylcholine on the filtration coefficient in intact dog lungs

NASA Technical Reports Server (NTRS)

Butler, B. D.; Davies, I.; Drake, R. E.

1989-01-01

Lysophosphatidylcholine (lyso-Pc) is a lysophospholipid normally found in low concentrations in the lung. At high concentrations lyso-Pc, instilled into the airways, causes pulmonary edema. The hypothesis was tested that the edema caused by lyso-Pc was due to an increase in pulmonary microvascular membrane permeability. In 11 anesthetized dogs, the left lower lobes (LLL) were continuously weighed while lyso-Pc (20 mM) was instilled into the LLL airways. After 30 min, the microvascular membrane fluid filtration coefficient (Kf) was determined from the relationship between the rate of LLL weight gain and the pulmonary microvascular pressure. Kf was not significantly different between the lyso-Pc-treated lobes vs control lobes. The data do not support the hypothesis that lyso-Pc, instilled into the airways, causes an increase in pulmonary microvascular permeability.

Acyl-chain remodeling of dioctanoyl-phosphatidylcholine in Saccharomyces cerevisiae mutant defective in de novo and salvage phosphatidylcholine synthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kishino, Hideyuki; Eguchi, Hiroki; Takagi, Keiko

2014-03-07

Highlights: • Dioctanoyl-PC (diC8PC) supported growth of a yeast mutant defective in PC synthesis. • diC8PC was converted to PC species containing longer acyl residues in the mutant. • Both acyl residues of diC8PC were replaced by longer fatty acids in vitro. • This system will contribute to the elucidation of the acyl chain remodeling of PC. - Abstract: A yeast strain, in which endogenous phosphatidylcholine (PC) synthesis is controllable, was constructed by the replacement of the promoter of PCT1, encoding CTP:phosphocholine cytidylyltransferase, with GAL1 promoter in a double deletion mutant of PEM1 and PEM2, encoding phosphatidylethanolamine methyltransferase and phospholipidmore » methyltransferase, respectively. This mutant did not grow in the glucose-containing medium, but the addition of dioctanoyl-phosphatidylcholine (diC8PC) supported its growth. Analyses of the metabolism of {sup 13}C-labeled diC8PC ((methyl-{sup 13}C){sub 3}-diC8PC) in this strain using electrospray ionization tandem mass spectrometry revealed that it was converted to PC species containing acyl residues of 16 or 18 carbons at both sn-1 and sn-2 positions. In addition, both acyl residues of (methyl-{sup 13}C){sub 3}-diC8PC were replaced with 16:1 acyl chains in the in vitro reaction using the yeast cell extract in the presence of palmitoleoyl-CoA. These results indicate that PC containing short acyl residues was remodeled to those with acyl chains of physiological length in yeast.« less

Singular Stokes-polarimetry as new technique for metrology and inspection of polarized speckle fields

NASA Astrophysics Data System (ADS)

Soskin, Marat S.; Denisenko, Vladimir G.; Egorov, Roman I.

2004-08-01

Polarimetry is effective technique for polarized light fields characterization. It was shown recently that most full "finger-print" of light fields with arbitrary complexity is network of polarization singularities: C points with circular polarization and L lines with variable azimuth. The new singular Stokes-polarimetry was elaborated for such measurements. It allows define azimuth, eccentricity and handedness of elliptical vibrations in each pixel of receiving CCD camera in the range of mega-pixels. It is based on precise measurement of full set of Stokes parameters by the help of high quality analyzers and quarter-wave plates with λ/500 preciseness and 4" adjustment. The matrices of obtained data are processed in PC by special programs to find positions of polarization singularities and other needed topological features. The developed SSP technique was proved successfully by measurements of topology of polarized speckle-fields produced by multimode "photonic-crystal" fibers, double side rubbed polymer films, biomedical samples. Each singularity is localized with preciseness up to +/- 1 pixel in comparison with 500 pixels dimensions of typical speckle. It was confirmed that network of topological features appeared in polarized light field after its interaction with specimen under inspection is exact individual "passport" for its characterization. Therefore, SSP can be used for smart materials characterization. The presented data show that SSP technique is promising for local analysis of properties and defects of thin films, liquid crystal cells, optical elements, biological samples, etc. It is able discover heterogeneities and defects, which define essentially merits of specimens under inspection and can"t be checked by usual polarimetry methods. The detected extra high sensitivity of polarization singularities position and network to any changes of samples position and deformation opens quite new possibilities for sensing of deformations and displacement of checked elements in the sub-micron range.

Down-regulation of osmotin (PR5) gene by virus-induced gene silencing (VIGS) leads to susceptibility of resistant Piper colubrinum Link. to the oomycete pathogen Phytophthora capsici Leonian.

PubMed

Anu, K; Jessymol, K K; Chidambareswaren, M; Gayathri, G S; Manjula, S

2015-06-01

Piper colubrinum Link., a distant relative of Piper nigrum L., is immune to the oomycete pathogen Phytophthora capsici Leonian that causes 'quick wilt' in cultivated black pepper (P. nigrum). The osmotin, PR5 gene homologue, earlier identified from P. colubrinum, showed significant overexpression in response to pathogen and defense signalling molecules. The present study focuses on the functional validation of P. colubrinum osmotin (PcOSM) by virus induced gene silencing (VIGS) using Tobacco Rattle Virus (TRV)-based vector. P. colubrinum plants maintained under controlled growth conditions in a growth chamber were infiltrated with Agrobacterium carrying TRV empty vector (control) and TRV vector carrying PcOSM. Three weeks post infiltration, viral movement was confirmed in newly emerged leaves of infiltrated plants by RT-PCR using TRV RNA1 and TRV RNA2 primers. Semi-quantitative RT-PCR confirmed significant down-regulation of PcOSM gene in TRV-PcOSM infiltrated plant compared with the control plants. The control and silenced plants were challenged with Phytophthora capsici which demonstrated that knock-down of PcOSM in P. colubrinum leads to increased fungal mycelial growth in silenced plants compared to control plants, which was accompanied by decreased accumulation of H2O2 as indicated by 3,3'-diaminobenzidine (DAB) staining. Thus, in this study, we demonstrated that Piper colubrinum osmotin gene is required for resisting P. capsici infection and has possible role in hypersensitive cell death response and oxidative burst signaling during infection.

Proposals for the implementation of the variants of automatic control of the telescope AZT-2

NASA Astrophysics Data System (ADS)

Shavlovskyi, V. I.; Puha, S. P.; Vidmachenko, A. P.; Volovyk, D. V.; Puha, G. P.; Obolonskyi, V. O.; Kratko, O. O.; Stefurak, M. V.

2018-05-01

Based on the experience of astronomical observations, structural features and results of the review of the technical state of the mechanism of the telescope AZT-2 in the Main Astronomical Observatory of NAS of Ukraine, in 2012 it was decided to carry out works on its modernization. To this end, it was suggested that the telescope control system should consist of angle sensors on the time axis "alpha" and the axis "delta", personal computer (PC), corresponding software, power control unit, and rotation system of telescope. The angle sensor should be absolute, with a resolution of better than 10 angular minutes. The PC should perform the functions of data processing from the angle sensor, and control the power node. The developed software allows the operator to direct the telescope in an automatic mode, and to set the necessary parameters of the system. With using of PC, the power control node will directly control the engine of the rotation system.

The cell-specific pattern of cholecystokinin peptides in endocrine cells versus neurons is governed by the expression of prohormone convertases 1/3, 2, and 5/6.

PubMed

Rehfeld, Jens F; Bundgaard, Jens R; Hannibal, Jens; Zhu, Xiaorong; Norrbom, Christina; Steiner, Donald F; Friis-Hansen, Lennart

2008-04-01

Most peptide hormone genes are, in addition to endocrine cells, also expressed in neurons. The peptide hormone cholecystokinin (CCK) is expressed in different molecular forms in cerebral neurons and intestinal endocrine cells. To understand this difference, we examined the roles of the neuroendocrine prohormone convertases (PC) 1/3, PC2, and PC5/6 by measurement of proCCK, processing intermediates and bioactive, alpha-amidated, and O-sulfated CCK peptides in cerebral and jejunal extracts of null mice, controls, and in the PC5/6-expressing SK-N-MC cell-line. In PC1/3 null mice, the synthesis of bioactive CCK peptide in the gut was reduced to 3% of the translational product, all of which was in the form of alpha-amidated and tyrosine O-sulfated CCK-22, whereas the neuronal synthesis in the brain was largely unaffected. This is opposite to the PC2 null mice in which only the cerebral synthesis was affected. SK-N-MC cells, which express neither PC1/3 nor PC2, synthesized alone the processing intermediate, glycine-extended CCK-22. Immunocytochemistry confirmed that intestinal endocrine CCK cells in wild-type mice express PC1/3 but not PC2. In contrast, cerebral CCK neurons contain PC2 and only little, if any, PC1/3. Taken together, the data indicate that PC1/3 governs the endocrine and PC2 the neuronal processing of proCCK, whereas PC5/6 contributes only to a modest endocrine synthesis of CCK-22. The results suggest that the different peptide patterns in the brain and the gut are due to different expression of PCs.

Different postconditioning cycles affect prognosis of aged patients undergoing primary percutaneous coronary intervention.

PubMed

Zhang, Jie; Zhang, Xin; Cui, Yuqi; Ferdous, Misbahul; Cui, Lianqun; Zhao, Peng

2017-07-17

Postconditioning can affect the infarct size in acute myocardial infarction (AMI). However, few studies show an effect of different postconditioning cycles on AMI aged patients. This study sought to assess the effect of different postconditioning cycles on prognosis in aged patients with AMI who underwent primary percutaneous coronary intervention (PCI). 74 aged patients were randomly assigned to three groups. Control group; PC-1 group accepted postconditioning 4 cycles of 30 s inflation and 30 s deflation; PC-2 group accepted postconditioning 4 cycles of 60 s. Creatine kinase MB (CK-MB), troponin I (cTnI), high-sensitive C-reactive protein (hs-CRP) and corrected Thrombolysis in Myocardial Infarction (TIMI) frame counts (CTFC) were analyzed before andafter treatment. All patients received an echocardiographic examination for whole heart function, wall motion score index (WMSI) and single-photon emission computed tomography (SPECT) examination at 7 days and 6 months after treatment. S: The peak of CK-MB, postoperative 72 h cTnI and CTFC were significantly attenuated by postconditioning when compared with the control group. The hs-CRP of the postconditioning group was lower than the control group 24 h postoperative. No difference was observed between PC-1 and PC-2 group about the effect described above. At 7 days, heart function in the postconditioning group was improved when compared with the control group. At 6 months, the WMSI and SPECT score significantly reduced in the PC-2 group compared with the control and PC-1 groups, but there was no difference among the three groups about echo data except the left ventricular end-systolic diameter. Postconditioning is significantly beneficial to prognosis in aged patients with AMI. The cardiac protective effect of 4 cycles of 60 s procedure was observed in WMSI and SPECT. It is favorable to implement this procedure in aged patients with AMI in clinic.

Search for liquids electrospraying the smallest possible nanodrops in vacuo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alonso-Matilla, R.; Fernández-García, J.; Congdon, H.

2014-12-14

Prior work with electrosprays in vacuum of mixtures of ionic liquids (ILs) and the moderately high boiling point (T{sub b}) solvents formamide (FM) and propylene carbonate (PC) (T{sub b} of 210 and 241 °C) has shown that the charged drops produced have reasonably narrow charge/mass distributions, controllable over a wide mass/charge range. This enables their use as propellants in electrical propulsion with specific impulse I{sub sp} varying from a few hundred to a few thousand seconds (10 kV beam energy) and with excellent propulsion efficiency. However, some limitations are imposed by the finite room temperature volatility of FM and PC. Here, wemore » seek improved performance from propellants based on the polar but viscous solvent Sulfolane (SF; ε = 43.2, μ = 10.3 cP) and the low viscosity but less polar solvent tributyl phosphate (TBP; ε = 8.9, μ = 3.4 cP), both with T{sub b} > 280 °C. Neither TBP nor its low viscosity mixtures with SF achieve the electrical conductivities needed to yield high I{sub sp}. Most ILs used in SF/IL mixtures tested were based on the 1-ethyl-3-methylimidazolium (EMI) or 1,3-dimethylimidazolium (DMI) cations, including EMI-BF{sub 4}, EMI-N(CN){sub 2}, and DMI-N(CN){sub 2}. These combinations reach high conductivities, some approaching 3 S/m, but have limited propulsive performance because evaporation of ions directly from the electrified meniscus produces undesirable mixed beams of drops and ions. Exceptional characteristics are found in mixtures of SF with ethylammonium nitrate (EAN), where the small EA{sup +} cation is strongly bound to the solvent, greatly delaying ion evaporation from the meniscus. Evidence on the formation of nano-jets with diameters as small as 1 nm is seen. Although unprecedented, this finding agrees with what would be expected if ion evaporation were suppressed. SF/EAN mixtures thus provide the best available sources to produce the smallest possible nanodrops, minimally polluted by ions.« less

Examining Perceived Control Level and Instability as Predictors of First-Year College Students' Academic Achievement

ERIC Educational Resources Information Center

Stupnisky, Robert H.; Perry, Raymond P.; Hall, Nathan C.; Guay, Frederic

2012-01-01

The aim of the present study was to examine the intraindividual level and instability of perceived academic control (PC) among first-year college students, and their predictive effects on academic achievement. Two studies were conducted measuring situational (state) PC on different schedules: Study 1 (N = 242) five times over a 6-month period and…

Hereditary pancreatic cancer: molecular bases and their application in diagnosis and clinical management: a guideline of the TTD group.

PubMed

Segura, P Pérez; Ponce, C Guillén; Ramón Y Cajal, T; Blanch, R Serrano; Aranda, E

2012-08-01

Pancreatic carcinoma (PC) represents the fourth leading cause of cancer death in Spain with a death rate of 2,400 males and 2,000 females per year. Poor outcome related to its silent nature and the lack of reliable secondary prevention measures translate into advanced-stage diagnosis, 75 % of deaths within the first year of diagnosis and 5-year survival rate of <5 %. Family history was first recognized as a risk factor for PC. Further population-based and case-control studies subsequently found that 7.8 % of patients with PC have a family history of the same tumor and individuals with a first-degree relative with PC have a 3.2-fold increased risk of developing PC. Overall, it is estimated that up to 10 % of PC have a familial component. However, known genetic syndromes account for <20 % of the observed familial aggregation of PC. We review the most important aspects in epidemiology, molecular biology and clinical management of familial PC.

GPI-anchored proteins are confined in subdiffraction clusters at the apical surface of polarized epithelial cells.

PubMed

Paladino, Simona; Lebreton, Stéphanie; Lelek, Mickaël; Riccio, Patrizia; De Nicola, Sergio; Zimmer, Christophe; Zurzolo, Chiara

2017-12-01

Spatio-temporal compartmentalization of membrane proteins is critical for the regulation of diverse vital functions in eukaryotic cells. It was previously shown that, at the apical surface of polarized MDCK cells, glycosylphosphatidylinositol (GPI)-anchored proteins (GPI-APs) are organized in small cholesterol-independent clusters of single GPI-AP species (homoclusters), which are required for the formation of larger cholesterol-dependent clusters formed by multiple GPI-AP species (heteroclusters). This clustered organization is crucial for the biological activities of GPI-APs; hence, understanding the spatio-temporal properties of their membrane organization is of fundamental importance. Here, by using direct stochastic optical reconstruction microscopy coupled to pair correlation analysis (pc-STORM), we were able to visualize and measure the size of these clusters. Specifically, we show that they are non-randomly distributed and have an average size of 67 nm. We also demonstrated that polarized MDCK and non-polarized CHO cells have similar cluster distribution and size, but different sensitivity to cholesterol depletion. Finally, we derived a model that allowed a quantitative characterization of the cluster organization of GPI-APs at the apical surface of polarized MDCK cells for the first time. Experimental FRET (fluorescence resonance energy transfer)/FLIM (fluorescence-lifetime imaging microscopy) data were correlated to the theoretical predictions of the model. © 2017 The Author(s).

European VLBI network observations of fourteen GHz-peaked-spectrum radio sources at 5 GHz

NASA Astrophysics Data System (ADS)

Xiang, L.; Reynolds, C.; Strom, R. G.; Dallacasa, D.

2006-08-01

We present the results of EVN polarization observations of fourteen GHz-Peaked-Spectrum (GPS) radio sources at 5 GHz. These sources were selected from bright GPS source samples and we aimed at finding Compact Symmetric Objects (CSOs). We have obtained full polarization 5 GHz VLBI observations of 14 sources providing information on their source structure and spectral indices. The results show that two core-jet sources 1433-040 and DA193, out of 14 GPS sources, exhibit integrated fractional polarizations of 3.6% and 1.0% respectively. The other 12 sources have no clear detection of pc-scale polarization. The results confirm that the GPS sources generally have very low polarization at 5 GHz. The sources 1133+432, 1824+271 and 2121-014 are confirmed as CSOs. Three new CSOs 0914+114, 1518+046 and 2322-040 (tentative) have been classified on the basis of 5 GHz images and spectral indices. The sources 1333+589, 1751+278 and 2323+790 can be classified either as compact doubles, and then they are likely CSO candidates or core-jet sources; further observations are needed for an appropriate classification; 0554-026, 1433-040 and 1509+054 are core-jet sources. In addition, we estimate that a component in the jet of quasar DA193 has superluminal motion of 3.3±0.6 h-1 c in 5.5 years.

KSC-98pc1822

NASA Image and Video Library

1998-12-02

KENNEDY SPACE CENTER, FLA. -- On Pad 17B, Cape Canaveral Air Station, a solid rocket booster waits for mating with the Delta II rocket (in background) carrying the Mars Polar Lander. The rocket will be used to launch the Mars Polar Lander on Jan. 3, 1999. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. It is the second spacecraft to be launched in a pair of Mars '98 missions. The first is the Mars Climate Orbiter, to be launched aboard a Delta II rocket from Launch Complex 17A in December 1998

KSC-98pc1827

NASA Image and Video Library

1998-12-02

KENNEDY SPACE CENTER, FLA. -- The fairing for the upper stages of the Delta II rocket carrying the Mars Polar Lander arrives at Pad 17B, Cape Canaveral Air Station. The rocket will be used to launch the Mars Polar Lander on Jan. 3, 1999. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. It is the second spacecraft to be launched in a pair of Mars '98 missions. The first is the Mars Climate Orbiter, to be launched aboard a Delta II rocket from Launch Complex 17A in December 1998

Pressure variation of Rashba spin splitting toward topological transition in the polar semiconductor BiTeI

NASA Astrophysics Data System (ADS)

Ideue, T.; Checkelsky, J. G.; Bahramy, M. S.; Murakawa, H.; Kaneko, Y.; Nagaosa, N.; Tokura, Y.

2014-10-01

BiTeI is a polar semiconductor with gigantic Rashba spin-split bands in bulk. We have investigated the effect of pressure on the electronic structure of this material via magnetotransport. Periods of Shubunikov-de Haas (SdH) oscillations originating from the spin-split outer Fermi surface and inner Fermi surface show disparate responses to pressure, while the carrier number derived from the Hall effect is unchanged with pressure. The associated parameters which characterize the spin-split band structure are strongly dependent on pressure, reflecting the pressure-induced band deformation. We find the SdH oscillations and transport response are consistent with the theoretically proposed pressure-induced band deformation leading to a topological phase transition. Our analysis suggests the critical pressure for the quantum phase transition near Pc=3.5 GPa.

Influence of surfactants on the effectiveness of bleaching gels.

PubMed

Caneppele, Taciana Marco Ferraz; Torres, Carlos Rocha Gomes

2011-02-01

This study evaluated the influence of surfactants on the effectiveness of 35% hydrogen peroxide (HP) and 10% carbamide peroxide (CP) bleaching gels. One hundred and forty bovine teeth were used, which were stained by immersion in a coffee, red wine, and tobacco mixture for 7 days. At the end of this process, the color measurement at baseline was taken with the Vita Easyshade spectrophotometer. The teeth were divided into seven groups: (a) negative control (NC), (b) positive control for HP (PC-35), (c) HP + Tween 20 (T20-35), (d) HP + laurel sodium sulfate (LSS-35), (e) positive control for CP (PC-10), (f) CP + Tween 20 (T20-10), and (g) CP + laurel sodium sulfate (LSS-10). Group NC was kept in artificial saliva for 21 days. Groups PC-35, T20-35, and LSS 35 received three applications of bleaching gel for 10 min; the process was repeated after 7 days. Groups PC-10, T20-10, and LSS-10 received the gel for 8 h per day for 14 days. After the bleaching process, the final color was measured. The analysis of variance and Tukey tests showed statistically significant differences for the parameters of ∆L, ∆b, and ∆E of the HP gels with surfactant and positive control group (PC-35). Within the limits of this in vitro study, the addition of surfactants to HP bleaching gel increased the bleaching effectiveness.

A Comparative Study of Probability Collectives Based Multi-agent Systems and Genetic Algorithms

NASA Technical Reports Server (NTRS)

Huang, Chien-Feng; Wolpert, David H.; Bieniawski, Stefan; Strauss, Charles E. M.

2005-01-01

We compare Genetic Algorithms (GA's) with Probability Collectives (PC), a new framework for distributed optimization and control. In contrast to GA's, PC-based methods do not update populations of solutions. Instead they update an explicitly parameterized probability distribution p over the space of solutions. That updating of p arises as the optimization of a functional of p. The functional is chosen so that any p that optimizes it should be p peaked about good solutions. The PC approach works in both continuous and discrete problems. It does not suffer from the resolution limitation of the finite bit length encoding of parameters into GA alleles. It also has deep connections with both game theory and statistical physics. We review the PC approach using its motivation as the information theoretic formulation of bounded rationality for multi-agent systems. It is then compared with GA's on a diverse set of problems. To handle high dimensional surfaces, in the PC method investigated here p is restricted to a product distribution. Each distribution in that product is controlled by a separate agent. The test functions were selected for their difficulty using either traditional gradient descent or genetic algorithms. On those functions the PC-based approach significantly outperforms traditional GA's in both rate of descent, trapping in false minima, and long term optimization.

Controlling insulin release from reverse hexagonal (HII) liquid crystalline mesophase by enzymatic lipolysis.

PubMed

Mishraki-Berkowitz, Tehila; Cohen, Guy; Aserin, Abraham; Garti, Nissim

2018-01-01

In the present study we aimed to control insulin release from the reverse hexagonal (H II ) mesophase using Thermomyces lanuginosa lipase (TLL) in the environment (outer TLL) or within the H II cylinders (inner TLL). Two insulin-loaded systems differing by the presence (or absence) of phosphatidylcholine (PC) were examined. In general, incorporation of PC into the H II interface (without TLL) increased insulin release, as a more cooperative system was formed. Addition of TLL to the systems' environments resulted in lipolysis of the H II structure. In the absence of PC, the lipolysis was more dominant and led to a significant increase in insulin release (50% after 8h). However, the presence of PC stabilized the interface, hindering the lipolysis, and therefore no impact on the release profile was detected during the first 8h. Entrapment of TLL within the H II cylinders (with and without PC) drastically increased insulin release in both systems up to 100%. In the presence of PC insulin released faster and the structure was more stable. Consequently, the presence of lipases (inner or outer) both enhanced the destruction of the carrier, and provided sustained release of the entrapped insulin. Copyright © 2017 Elsevier B.V. All rights reserved.

Origin of the energy level alignment at organic/organic interfaces: The role of structural defects

NASA Astrophysics Data System (ADS)

Bussolotti, Fabio; Yang, Jinpeng; Hinderhofer, Alexander; Huang, Yuli; Chen, Wei; Kera, Satoshi; Wee, Andrew T. S.; Ueno, Nobuo

2014-03-01

In this paper, the electronic properties of as-deposited and N2-exposedCuPc/F16CuPc interface, a prototype system for organic photovoltaic applications, are investigated by using ultralow background, high-sensitivity photoemission spectroscopy. It is found that (i) N2 exposure significantly modifies the energy level alignment (ELA) at the interface between CuPc and F16CuPc layer and (ii) the direction of the N2-induced energy level shift of the CuPc depends on the position of the Fermi level (EF) in the CuPc highest occupied molecular orbital-lowest unoccupied molecular orbital gap of the as-deposited film. These observations are related to the changes in the density of gap states (DOGS) produced by structural imperfections in the molecular packing geometry, as introduced by the N2 penetration into the CuPc layer. This result demonstrates the key role of structure-induced DOGS in controlling the ELA at organic/organic interfaces.

A PC-based Workstation for Robotic Discectomy

NASA Technical Reports Server (NTRS)

Casadei, C.; Fiorini, P.; Martelli, S.; Montanari, M.; Morri, A.

1998-01-01

Ths paper describes a PC-based controller for robot-assisted minimally invasive surgery. The development is motivated by the need of reducing the exposure of operating room personnel to X-rays during surgical procedures such as percutanrous discectomy.

Selective nucleation of iron phthalocyanine crystals on micro-structured copper iodide.

PubMed

Rochford, Luke A; Ramadan, Alexandra J; Heutz, Sandrine; Jones, Tim S

2014-12-14

Morphological and structural control of organic semiconductors through structural templating is an efficient route by which to tune their physical properties. The preparation and characterisation of iron phthalocyanine (FePc)-copper iodide (CuI) bilayers at elevated substrate temperatures is presented. Thin CuI(111) layers are prepared which are composed of isolated islands rather than continuous films previously employed in device structures. Nucleation in the early stages of FePc growth is observed at the edges of islands rather than on the top (111) faces with the use of field emission scanning electron microscopy (FE-SEM). Structural measurements show two distinct polymorphs of FePc, with CuI islands edges nucleating high aspect ratio FePc crystallites with modified intermolecular spacing. By combining high substrate temperature growth and micro-structuring of the templating CuI(111) layer structural and morphological control of the organic film is demonstrated.

[Features of control of electromagnetic radiation emitted by personal computers].

PubMed

Pal'tsev, Iu P; Buzov, A L; Kol'chugin, Iu I

1996-01-01

Measurements of PC electromagnetic irradiation show that the main sources are PC blocks emitting the waves of certain frequencies. Use of wide-range detectors measuring field intensity in assessment of PC electromagnetic irradiation gives unreliable results. More precise measurements by selective devices are required. Thus, it is expedient to introduce a term "spectral density of field intensity" and its maximal allowable level. In this case a frequency spectrum of PC electromagnetic irradiation is divided into 4 ranges, one of which is subjected to calculation of field intensity for each harmonic frequency, and others undergo assessment of spectral density of field intensity.

Heat-acclimatization and pre-cooling: a further boost for endurance performance?

PubMed

Schmit, C; Le Meur, Y; Duffield, R; Robach, P; Oussedik, N; Coutts, A J; Hausswirth, C

2017-01-01

To determine if pre-cooling (PC) following heat-acclimatization (HA) can further improve self-paced endurance performance in the heat, 13 male triathletes performed two 20-km cycling time-trials (TT) at 35 °C, 50% relative humidity, before and after an 8-day training camp, each time with (PC) or without (control) ice vest PC. Pacing strategies, physiological and perceptual responses were assessed during each TT. PC and HA induced moderate (+10 ± 18 W; effect size [ES] 4.4 ± 4.6%) and very large (+28 ± 19 W; ES 11.7 ± 4.1%) increases in power output (PO), respectively. The overall PC effect became unclear after HA (+4 ± 14 W; ES 1.4 ± 3.0%). However, pacing analysis revealed that PC remained transiently beneficial post-HA, i.e., during the first half of the TT. Both HA and PC pre-HA were characterized by an enhanced PO without increased cardio-thermoregulatory or perceptual disturbances, while post-HA PC only improved thermal comfort. PC improved 20-km TT performance in unacclimatized athletes, but an 8-day HA period attenuated the magnitude of this effect. The respective converging physiological responses to HA and PC may explain the blunting of PC effectiveness. However, perceptual benefits from PC can still account for the small alterations to pacing noted post-HA. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Opportunistic testing versus organized prostate-specific antigen screening: outcome after 18 years in the Göteborg randomized population-based prostate cancer screening trial.

PubMed

Arnsrud Godtman, Rebecka; Holmberg, Erik; Lilja, Hans; Stranne, Johan; Hugosson, Jonas

2015-09-01

It has been shown that organized screening decreases prostate cancer (PC) mortality, but the effect of opportunistic screening is largely unknown. To compare the ability to reduce PC mortality and the risk of overdiagnosis between organized and opportunistic screening. The Göteborg screening study invited 10 000 randomly selected men for prostate-specific antigen (PSA) testing every 2 yr since 1995, with a prostate biopsy recommended for men with PSA ≥2.5 ng/ml. The control group of 10 000 men not invited has been exposed to a previously reported increased rate of opportunistic PSA testing. Both groups were followed until December 31, 2012. Observed cumulative PC incidence and mortality rates in both groups were calculated using the actuarial method. Using historical data from 1990-1994 (pre-PSA era), we calculated expected PC incidence and mortality rates in the absence of any PSA testing. The number needed to invite (NNI) and the number needed to diagnose (NND) were calculated by comparing the expected versus observed incidence and mortality rates. At 18 yr, 1396 men were diagnosed with PC and 79 men died of PC in the screening group, compared to 962 and 122, respectively, in the control group. In the screening group, the observed cumulative PC incidence/mortality was 16%/0.98% compared to expected values of 6.8%/1.7%. The corresponding values for the control group were 11%/1.5% and 6.9%/1.7%. Organized screening was associated with an absolute PC-specific mortality reduction of 0.72% (95% confidence interval [CI] 0.50-0.94%) and relative risk reduction of 42% (95% CI 28-54%). There was an absolute reduction in PC deaths of 0.20% (95% CI -0.06% to 0.47%) and a relative risk reduction of 12% (95% CI -5 to 26%) associated with opportunistic PSA testing. NNI and NND were 139 (95% CI 107-200) and 13 for organized biennial screening and 493 (95% CI 213- -1563) and 23 for opportunistic screening. The extent of opportunistic screening could not be measured; incidence trends were used as a proxy. Organized screening reduces PC mortality but is associated with overdiagnosis. Opportunistic PSA testing had little if any effect on PC mortality and resulted in more overdiagnosis, with almost twice the number of men needed to be diagnosed to save one man from dying from PC compared to men offered an organized biennial screening program. Prostate-specific antigen (PSA) screening within the framework of an organized program seems more effective than unorganized screening. Copyright © 2014 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Effect of structure and morphology on thermal and electrical properties of polycarbonate film capacitors

NASA Astrophysics Data System (ADS)

Yen, S. P. S.; Lewis, C. R.

Research is reported to identify polycarbonate (PC) film characteristics and fabrication procedures which extend the reliable performance range of PC capacitors to 125 C without derating, and establish quality control techniques and transfer technology to US PC film manufacturers. The approach chosen to solve these problems was to develop techniques for fabricating biaxially oriented (BX) 2 microns or thinner PC film with a low dissipation factor up to 140 C; isotropic dimensional stability; high crystallinity; and high voltage breakdown strength. The PC film structure and morphology was then correlated to thermal and electrical capacitor behavior. Analytical techniques were developed to monitor film quality during capacitor fabrication, and as a result, excellent performance was demonstrated during initial capacitor testing.

OCEAN-PC and a distributed network for ocean data

NASA Technical Reports Server (NTRS)

Mclain, Douglas R.

1992-01-01

The Intergovernmental Oceanographic Commission (IOC) wishes to develop an integrated software package for oceanographic data entry and access in developing countries. The software, called 'OCEAN-PC', would run on low cost PC microcomputers and would encourage and standardize: (1) entry of local ocean observations; (2) quality control of the local data; (3) merging local data with historical data; (4) improved display and analysis of the merged data; and (5) international data exchange. OCEAN-PC will link existing MS-DOS oceanographic programs and data sets with table-driven format conversions. Since many ocean data sets are now being distributed on optical discs (Compact Discs - Read Only Memory, CD-ROM, Mass et al. 1987), OCEAN-PC will emphasize access to CD-ROMs.

Solubility of pharmaceuticals: A comparison between SciPharma, a PC-SAFT-based approach, and NRTL-SAC

NASA Astrophysics Data System (ADS)

Bouillot, Baptiste; Spyriouni, Theodora; Teychené, Sébastien; Biscans, Béatrice

2017-04-01

The solubility of seven pharmaceutical compounds (paracetamol, benzoic acid, 4-aminobenzoic acid, salicylic acid, ibuprofen, naproxen and temazepam) in pure and mixed solvents as a function of temperature is calculated with SciPharma, a semi-empirical approach based on PC-SAFT, and the NRTL-SAC model. To conduct a fair comparison between the approaches, the parameters of the compounds were regressed against the same solubility data, chosen to account for hydrophilic, polar and hydrophobic interactions. Only these solubility data were used by both models for predicting solubility in other pure and mixed solvents for which experimental data were available for comparison. A total of 386 pure solvent data points were used for the comparison comprising one or more temperatures per solvent. SciPharma is found to be more accurate than NRTL-SAC on the pure solvent data used especially in the description of the temperature dependence. This is due to the appropriate parameterization of the pharmaceuticals and the temperature-dependent description of the activity coefficient in PC-SAFT. The solubility in mixed solvents is predicted satisfactorily with SciPharma. NRTL-SAC tends to overestimate the solubility in aqueous solutions of alcohols or shows invariable solubility with composition in other cases.

Early Palliative Care for Patients With Brain Metastases Decreases Inpatient Admissions and Need for Imaging Studies.

PubMed

Habibi, Akram; Wu, S Peter; Gorovets, Daniel; Sansosti, Alexandra; Kryger, Marc; Beaudreault, Cameron; Chung, Wei-Yi; Shelton, Gary; Silverman, Joshua; Lowy, Joseph; Kondziolka, Douglas

2018-01-01

Early encounters with palliative care (PC) can influence health-care utilization, clinical outcome, and cost. To study the effect of timing of PC encounters on brain metastasis patients at an academic medical center. All patients diagnosed with brain metastases from January 2013 to August 2015 at a single institution with inpatient and/or outpatient PC records available for review (N = 145). Early PC was defined as having a PC encounter within 8 weeks of diagnosis with brain metastases; late PC was defined as having PC after 8 weeks of diagnosis. Propensity score matched cohorts of early (n = 46) and late (n = 46) PC patients were compared to control for differences in age, gender, and Karnofsky Performance Status (KPS) at diagnosis. Details of the palliative encounter, patient outcomes, and health-care utilization were collected. Early PC versus late PC patients had no differences in baseline KPS, age, or gender. Early PC patients had significantly fewer number of inpatient visits per patient (1.5 vs 2.9; P = .004), emergency department visits (1.2 vs 2.1; P = .006), positron emission tomography/computed tomography studies (1.2 vs 2.7, P = .005), magnetic resonance imaging scans (5.8 vs 8.1; P = .03), and radiosurgery procedures (0.6 vs 1.3; P < .001). There were no differences in overall survival (median 8.2 vs 11.2 months; P = .2). Following inpatient admissions, early PC patients were more likely to be discharged home (59% vs 35%; P = .04). Timely PC consultations are advisable in this patient population and can reduce health-care utilization.

Use of 8-methoxypsoralen and long-wavelength ultraviolet radiation for decontamination of platelet concentrates

NASA Astrophysics Data System (ADS)

Corash, Laurence; Lin, Lily; Wiesehahn, Gary; Cimino, George

1992-06-01

Transmission of viral diseases through blood products remains a problem in transfusion medicine. A number of methods have been developed to inactivate viral pathogens in plasma and plasma fractions, including: dry heating, wet heating, solvent-detergent treatment, and immunoaffinity purification. While some of these methods successfully inactivate pathogenic viruses, inactivation may be incomplete or result in damage to labile plasma proteins and cells. We have developed a photochemical decontamination system (PCD) for platelet concentrates (PC) utilizing treatment with long wavelength ultraviolet radiation (UVA, 320 - 400 nm) and 8-methoxypsoralen (8-MOP). This system is capable of inactivating 25 - 30 logs/hr of bacteria E. coli or S. aureus, 6 logs/hr of bacteriophage fd, 0.9 log/hr of bacteriophage R17 and 1.1 logs/hr of feline leukemia virus (FeLV) in PC. Immediately following 6 hrs of PCD treatment, platelet integrity and function of PCD treated and control PC were equivalent. After overnight storage PCD treated and control PC platelet properties were equal, but there was a slight reduction in TXB-2 production of PCD treated PC compared to controls. Following PCD treatment, PC were stored for 48 to 96 hrs. Platelet counts, morphology scores, extracellular LDH levels, aggregation response, dense body (db) content, and alpha granule ((alpha) g) content of PCD treated and control PC were comparable. We assessed the ability of the PCD technique to inactivate intracellular and extracellular virus, quantified the degree of DNA adduct formation in contaminating lymphocytes, and measured the inhibition of polymerase chain reaction (PCR) mediated amplification of intracellular DNA. High titers of cell-free murine cytomegalovirus added to human platelet concentrates (final concentration 106) were inactivated by PCD within 30 min. Cat renal fibroblasts infected at high levels with feline rhinotracheitis virus (FeRTV) were seeded into PC followed by PCD treatment with inactivation of 4.8 logs of FeRTV within 10 minutes. Purified human lymphocytes were seeded into PC and treated with PCD in the presence of 3H 8-MOP. Six hours of PCD treatment resulted in the formation of 9.3 to 12.8 8-MOP adducts per 1000 base pairs (bp) of DNA. PCR amplification of a 242 bp segment at the HLA-DQ(alpha) locus was examined. Inhibition of PCR DNA amplification was dependent on the numbers of 8-MOP adducts formed, and no amplification was present when greater than 12 adducts per 1000 bp were formed. These studies indicate that PCD can effectively inactivate high titers of cell-associated and cell-free virus seeded into standard human PC. The efficiency of DNA adduct formation can be quantitated, and the level of 8-MOP adduct formation in lymphocytes contaminating PC is comparable to the level of adduct formation in cellular DNA reported in the absence of platelets.

Chrna2-Martinotti Cells Synchronize Layer 5 Type A Pyramidal Cells via Rebound Excitation

PubMed Central

Leão, Richardson N.; Edwards, Steven J.

2017-01-01

Martinotti cells are the most prominent distal dendrite–targeting interneurons in the cortex, but their role in controlling pyramidal cell (PC) activity is largely unknown. Here, we show that the nicotinic acetylcholine receptor α2 subunit (Chrna2) specifically marks layer 5 (L5) Martinotti cells projecting to layer 1. Furthermore, we confirm that Chrna2-expressing Martinotti cells selectively target L5 thick-tufted type A PCs but not thin-tufted type B PCs. Using optogenetic activation and inhibition, we demonstrate how Chrna2-Martinotti cells robustly reset and synchronize type A PCs via slow rhythmic burst activity and rebound excitation. Moreover, using optical feedback inhibition, in which PC spikes controlled the firing of surrounding Chrna2-Martinotti cells, we found that neighboring PC spike trains became synchronized by Martinotti cell inhibition. Together, our results show that L5 Martinotti cells participate in defined cortical circuits and can synchronize PCs in a frequency-dependent manner. These findings suggest that Martinotti cells are pivotal for coordinated PC activity, which is involved in cortical information processing and cognitive control. PMID:28182735

Androgen receptor CAG repeat polymorphisms in canine prostate cancer.

PubMed

Lai, C-L; L'Eplattenier, H; van den Ham, R; Verseijden, F; Jagtenberg, A; Mol, J A; Teske, E

2008-01-01

Relatively shorter lengths of the polymorphic polyglutamine repeat-1 of the androgen receptor (AR) have been associated with an increased risk of prostate cancer (PC) in humans. In the dog, there are 2 polymorphic CAG repeat (CAGr) regions. To investigate the relationship of CAGr length of the canine AR-gene and the development of PC. Thirty-two dogs with PC and 172 control dogs were used. DNA was extracted from blood. Both CAG repeats were amplified by polymerase chain reaction (PCR) and PCR products were sequenced. In dogs with PC, CAG-1 repeat length was shorter (P = .001) by an increased proportion of 10 repeats (P = .011) and no 12 repeats (P = .0017) than in the control dogs. No significant changes were found in CAG-3 length distribution. CAG-1 and CAG-3 polymorphisms proved not to be in linkage disequilibrium. Breed difference in allelic distribution was found in the control group. Of the prostate-disease sensitive breeds, a high percentage (64.5%) of the shortest haplotype 10/11 was found in the Doberman, whereas Beagles and German Pointers had higher haplotype 12/11 (47.1 and 50%). Bernese Mountain dogs and Bouvier dogs both shared a high percentage of 11 CAG-1 repeats and 13 CAG-3 repeats. Differences in (combined) allelic distributions among breeds were not significant. In this preliminary study, short CAG-1 repeats in the AR-gene were associated with an increased risk of developing canine PC. Although breed-specific differences in allelic distribution of CAG-1 and CAG-3 repeats were found, these could not be related to PC risk.

Primary Metabolism and Medium-Chain Fatty Acid Alterations Precede Long-Chain Fatty Acid Changes Impacting Neutral Lipid Metabolism in Response to an Anticancer Lysophosphatidylcholine Analogue in Yeast.

PubMed

Tambellini, Nicolas P; Zaremberg, Vanina; Krishnaiah, Saikumari; Turner, Raymond J; Weljie, Aalim M

2017-10-06

The nonmetabolizable lysophosphatidylcholine (LysoPC) analogue edelfosine is the prototype of a class of compounds being investigated for their potential as selective chemotherapeutic agents. Edelfosine targets membranes, disturbing cellular homeostasis. Is not clear at this point how membrane alterations are communicated between intracellular compartments leading to growth inhibition and eventual cell death. In the present study, a combined metabolomics/lipidomics approach for the unbiased identification of metabolic pathways altered in yeast treated with sublethal concentrations of the LysoPC analogue was employed. Mass spectrometry of polar metabolites, fatty acids, and lipidomic profiling was used to study the effects of edelfosine on yeast metabolism. Amino acid and sugar metabolism, the Krebs cycle, and fatty acid profiles were most disrupted, with polar metabolites and short-medium chain fatty acid changes preceding long and very long-chain fatty acid variations. Initial increases in metabolites such as trehalose, proline, and γ-amino butyric acid with a concomitant decrease in metabolites of the Krebs cycle, citrate and fumarate, are interpreted as a cellular attempt to offset oxidative stress in response to mitochondrial dysfunction induced by the treatment. Notably, alanine, inositol, and myristoleic acid showed a steady increase during the period analyzed (2, 4, and 6 h after treatment). Of importance was the finding that edelfosine induced significant alterations in neutral glycerolipid metabolism resulting in a significant increase in the signaling lipid diacylglycerol.

[Quantification of acetabular coverage in normal adult].

PubMed

Lin, R M; Yang, C Y; Yu, C Y; Yang, C R; Chang, G L; Chou, Y L

1991-03-01

Quantification of acetabular coverage is important and can be expressed by superimposition of cartilage tracings on the maximum cross-sectional area of the femoral head. A practical Autolisp program on PC AutoCAD has been developed by us to quantify the acetabular coverage through numerical expression of the images of computed tomography. Thirty adults (60 hips) with normal center-edge angle and acetabular index in plain X ray were randomly selected for serial drops. These slices were prepared with a fixed coordination and in continuous sections of 5 mm in thickness. The contours of the cartilage of each section were digitized into a PC computer and processed by AutoCAD programs to quantify and characterize the acetabular coverage of normal and dysplastic adult hips. We found that a total coverage ratio of greater than 80%, an anterior coverage ratio of greater than 75% and a posterior coverage ratio of greater than 80% can be categorized in a normal group. Polar edge distance is a good indicator for the evaluation of preoperative and postoperative coverage conditions. For standardization and evaluation of acetabular coverage, the most suitable parameters are the total coverage ratio, anterior coverage ratio, posterior coverage ratio and polar edge distance. However, medial coverage and lateral coverage ratios are indispensable in cases of dysplastic hip because variations between them are so great that acetabuloplasty may be impossible. This program can also be used to classify precisely the type of dysplastic hip.

Interface engineering to enhance the efficiency of conventional polymer solar cells by alcohol-/water-soluble C60 materials doped with alkali carbonates.

PubMed

Lai, Yu-Ying; Shih, Ping-I; Li, Yi-Peng; Tsai, Che-En; Wu, Jhong-Sian; Cheng, Yen-Ju; Hsu, Chain-Shu

2013-06-12

Two new C60-based n-type materials, EGMC-OH and EGMC-COOH, functionalized with hydrophilic triethylene glycol groups (TEGs), have been synthesized and employed in conventional polymer solar cells. With the assistance of the TEG-based surfactant, EGMC-OH and EGMC-COOH can be dissolved in highly polar solvents to implement the polar/nonpolar orthogonal solvent strategy, forming an electron modification layer (EML) without eroding the underlying active layer. Multilayer conventional solar cells on the basis of ITO/PEDOT:PSS/P3HT:PC61BM/EML/Ca/Al configuration with the insertion of the EGMC-OH and EGMC-COOH EML between the active layer and the electrode have thus been successfully realized by cost-effective solution processing techniques. Moreover, the electron conductivity of the EML can be improved by incorporating alkali carbonates into the EGMC-COOH EML. Compared to the pristine device with a PCE of 3.61%, the devices modified by the Li2CO3-doped EGMC-COOH EML achieved a highest PCE of 4.29%. Furthermore, we demonstrated that the formation of the EGMC-COOH EML can be utilized as a general approach in the fabrication of highly efficient multilayer conventional devices. With the incorporation of the EGMC-COOH doped with 40 wt % Li2CO3, the PCDCTBT-C8:PC71BM-based device exhibited a superior PCE of 4.51%, which outperformed the corresponding nonmodified device with a PCE of 3.63%.

The reconstituted P-glycoprotein multidrug transporter is a flippase for glucosylceramide and other simple glycosphingolipids.

PubMed

Eckford, Paul D W; Sharom, Frances J

2005-07-15

The Pgp (P-glycoprotein) multidrug transporter, which is linked to multidrug resistance in human cancers, functions as an efflux pump for non-polar drugs, powered by the hydrolysis of ATP at its nucleotide binding domains. The drug binding sites of Pgp appear to be located within the cytoplasmic leaflet of the membrane bilayer, suggesting that Pgp may function as a 'flippase' for hydrophobic compounds. Pgp has been shown to translocate fluorescent phospholipids, and it has been suggested that it may also interact with GlcCer (glucosylceramide). Here we use a dithionite fluorescence quenching technique to show that reconstituted Pgp can flip several NBD (nitrobenzo-2-oxa-1,3-diazole)-labelled simple glycosphingolipids, including NBD-GlcCer, from one leaflet of the bilayer to the other in an ATP-dependent, vanadate-sensitive fashion. The rate of NBD-GlcCer flipping was similar to that observed for NBD-labelled PC (phosphatidylcholine). NBD-GlcCer flipping was inhibited in a concentration-dependent, saturable fashion by various Pgp substrates and modulators, and inhibition correlated well with the Kd for binding to the protein. The addition of a second sugar to the headgroup of the glycolipid to form NBD-lactosylceramide drastically reduced the rate of flipping compared with NBD-PC, probably because of the increased size and polarity contributed by the additional sugar residue. We conclude that Pgp functions as a broad-specificity outwardly-directed flippase for simple glycosphingolipids and membrane phospholipids.

Ultrahigh Piezoelectric Properties in Textured (K,Na)NbO3 -Based Lead-Free Ceramics.

PubMed

Li, Peng; Zhai, Jiwei; Shen, Bo; Zhang, Shujun; Li, Xiaolong; Zhu, Fangyuan; Zhang, Xingmin

2018-02-01

High-performance lead-free piezoelectric materials are in great demand for next-generation electronic devices to meet the requirement of environmentally sustainable society. Here, ultrahigh piezoelectric properties with piezoelectric coefficients (d 33 ≈700 pC N -1 , d 33 * ≈980 pm V -1 ) and planar electromechanical coupling factor (k p ≈76%) are achieved in highly textured (K,Na)NbO 3 (KNN)-based ceramics. The excellent piezoelectric properties can be explained by the strong anisotropic feature, optimized engineered domain configuration in the textured ceramics, and facilitated polarization rotation induced by the intermediate phase. In addition, the nanodomain structures with decreased domain wall energy and increased domain wall mobility also contribute to the ultrahigh piezoelectric properties. This work not only demonstrates the tremendous potential of KNN-based ceramics to replace lead-based piezoelectrics but also provides a good strategy to design high-performance piezoelectrics by controlling appropriate phase and crystallographic orientation. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Prion Protein Regulates Iron Transport by Functioning as a Ferrireductase

PubMed Central

Singh, Ajay; Haldar, Swati; Horback, Katharine; Tom, Cynthia; Zhou, Lan; Meyerson, Howard; Singh, Neena

2017-01-01

Prion protein (PrPC) is implicated in the pathogenesis of prion disorders, but its normal function is unclear. We demonstrate that PrPC is a ferrireductase (FR), and its absence causes systemic iron deficiency in PrP knock-out mice (PrP−/−). When exposed to non-transferrin-bound (NTB) radioactive-iron (59FeCl3) by gastric-gavage, PrP−/− mice absorb significantly more 59Fe from the intestinal lumen relative to controls, indicating appropriate systemic response to the iron deficiency. Chronic exposure to excess dietary iron corrects this deficiency, but unlike wild-type (PrP+/+) controls that remain iron over-loaded, PrP−/− mice revert back to the iron deficient phenotype after 5 months of chase on normal diet. Bone marrow (BM) preparations of PrP−/− mice on normal diet show relatively less stainable iron, and this phenotype is only partially corrected by intraperitoneal administration of excess iron-dextran. Cultured PrP−/− BM-macrophages incorporate significantly less NTB-59Fe in the absence or presence of excess extracellular iron, indicating reduced uptake and/or storage of available iron in the absence of PrPC. When expressed in neuroblastoma cells, PrPC exhibits NAD(P)H-dependent cell-surface and intracellular FR activity that requires the copper-binding octa-peptide-repeat region and linkage to the plasma membrane for optimal function. Incorporation of NTB-59Fe by neuroblastoma cells correlates with FR activity of PrPC, implicating PrPC in cellular iron uptake and metabolism. These observations explain the correlation between PrPC expression and cellular iron levels, and the cause of iron imbalance in sporadic-Creutzfeldt-Jakob-disease brains where PrPC accumulates as insoluble aggregates. PMID:23478311

Subclinical Inflammation and Endothelial Dysfunction in Patients with Chronic Pancreatitis and Newly Diagnosed Pancreatic Cancer.

PubMed

Gasiorowska, A; Talar-Wojnarowska, R; Kaczka, A; Borkowska, A; Czupryniak, L; Małecka-Panas, E

2016-04-01

Recent studies have suggested that various cytokines may be important players in the development and progression of chronic pancreatitis (CP) and pancreatic adenocarcinoma (PC). We studied endothelial dysfunction and subclinical inflammation in patients with newly diagnosed pancreatic adenocarcinoma and CP. A total of 45 patients were included in the present investigation, 27 with CP and 18 with PC. In addition, the study included 13 age- and body weight-matched healthy subjects served as controls. In all subjects, plasma adiponectin, TNF-alfa, interleukin 6 (IL-6), interleukin 1beta (IL-1β), E-selectin, thrombomodulin, adhesion molecules ICAM and VCAM, and endothelin-1 were assessed. PC and CP patients as compared with controls had significantly greater plasma adiponectin (13,292 and 12,227 vs 5408 ng/ml; p < 0.0003), TNF-alfa (22.1 and 23.1 vs 13 pg/ml; p < 0.0002), and IL-6 (6.6 and 7.3 vs 3.3 pg/ml; p < 0.0001). Moreover, there was significantly higher concentration of ICAM (931 and 492 vs 290 ng/ml; p < 0.005) and VCAM (1511 and 1080 vs 840 ng/ml; p < 0.01) in PC and CP patients. When PC and CP patients with and without diabetes were considered separately, there was no difference in adiponectin, cytokines, and parameters of endothelial dysfunction. In summary, our data indicate that patients with CP and PC express high levels of several cytokines compared with healthy individuals, especially adiponectin, TNF-α and IL-6. Serum TNF-α and ICAM concentrations coordinately increase in advanced CP. Furthermore, especially in PC subjects, elevated markers of endothelial dysfunction are present. This study provides additional evidence that changes in inflammatory cytokine and adhesion molecules in PC and CP are not likely related to endocrine disorders.

Bile acids-mediated overexpression of MUC4 via FAK-dependent c-Jun activation in pancreatic cancer.

PubMed

Joshi, Suhasini; Cruz, Eric; Rachagani, Satyanarayana; Guha, Sushovan; Brand, Randall E; Ponnusamy, Moorthy P; Kumar, Sushil; Batra, Surinder K

2016-08-01

The majority of pancreatic cancer (PC) patients are clinically presented with obstructive jaundice with elevated levels of circulatory bilirubin and alkaline phosphatases. In the current study, we examined the implications of bile acids (BA), an important component of bile, on the pathophysiology of PC and investigated their mechanistic association in tumor-promoting functions. Integration of results from PC patient samples and autochthonous mouse models showed an elevated levels of BA (p < 0.05) in serum samples compared to healthy controls. Similarly, an elevated BA levels was observed in pancreatic juice derived from PC patients (p < 0.05) than non-pancreatic non-healthy (NPNH) controls, further establishing the clinical association of BA with the pathogenesis of PC. The tumor-promoting functions of BA were established by observed transcriptional upregulation of oncogenic MUC4 expression. Luciferase reporter assay revealed distal MUC4 promoter as the primary responsive site to BA. In silico analysis recognized two c-Jun binding sites at MUC4 distal promoter, which was biochemically established using ChIP assay. Interestingly, BA treatment led to an increased transcription and activation of c-Jun in a FAK-dependent manner. Additionally, BA receptor, namely FXR, which is also upregulated at transcriptional level in PC patient samples, was demonstrated as an upstream molecule in BA-mediated FAK activation, plausibly by regulating Src activation. Altogether, these results demonstrate that elevated levels of BA increase the tumorigenic potential of PC cells by inducing FXR/FAK/c-Jun axis to upregulate MUC4 expression, which is overexpressed in pancreatic tumors and is known to be associated with progression and metastasis of PC. Published by Elsevier B.V.

Effects of Phos-Chek G75-F and Silv-Ex on developing northern bobwhite quail (Colinus virginianus).

PubMed

Buscemi, D M; Hoffman, D J; Vyas, N B; Spann, J W; Kuenzel, W J

2002-10-01

Eggs of nesting birds situated in peripheral areas serving as fire breaks are at risk of being sprayed with fire control chemicals. Acute toxicity tests were conducted by immersing northern bobwhite quail eggs for 10 s in different water-based concentrations of Silv-Ex(R) (SE), a foam-suppressant chemical, and Phos-Chek(R) G75-F (PC), a fire retardant chemical, on day 4 or day 11 of incubation. An attempt was made to relate the treatment concentrations to the actual field application levels. Mortality appeared higher in most groups exposed on day 11 than on day 4, suggesting that on day 11 the extensive chorioallantoic vascular network permitted greater uptake of chemical. Only 24-60% of the embryos survived to hatch at exposure concentrations of 202, 269, and 454 g/L PC when treated on incubation day 11. At higher concentrations including 681956, and 1211 g/L PC, the compound did not completely dissolve in water and clumped on eggshells, resulting in greater hatching success. Exposures to SE at 100 g/L on incubation day 11 did not significantly affect hatching success of embryos but did significantly reduce the percent hematocrit in blood compared with controls. Incubation day 11 exposure to 202 and 1211 g/L PC led to a significant increase in plasma aspartate aminotransferase, and day 4 exposure to 1211 g/L PC resulted in a significant increase in alanine aminotransferase. In addition to elevated liver enzymes, these treatments resulted in a decrease in the number of hepatocyte profiles (1211 g/L PC at day 4 and day 11) and an increase in hepatocyte size (202 and 1211 g/L PC at day 11) in hatchlings. A combination of SE and PC was synergistic (202 g/L PC and 50 g/L SE) at day 11 of incubation with respect to decreased hatching success and reduced bone lengths. However, lower concentrations of SE (10 g/L or 30 g/L) combined with 202 g/L of PC appeared antagonistic. This may be due to SE, as a surfactant, altering the ability of PC to penetrate the egg. Our results show fewer adverse effects following exposure to SE than to PC; therefore application of SE may be less harmful to breeding bird populations.

Effects of Phos-Chek G75-F and Silv-Ex on developing Northern Bobwhite Quail (Colinus virginianus)

USGS Publications Warehouse

Buscemi, D.M.; Hoffman, D.J.; Vyas, N.B.; Spann, J.W.; Kuenzel, W.J.

2002-01-01

Eggs of nesting birds situated in peripheral areas serving as fire breaks are at risk of being sprayed with fire control chemicals. Acute toxicity tests were conducted by immersing northern bobwhite quail eggs for 10 s in different water-based concentrations of Silv-Ex? (SE), a foam-suppressant chemical, and Phos-Chek? G75-F (PC), a fire retardant chemical, on day 4 or day 11 of incubation. An attempt was made to relate the treatment concentrations to the actual field application levels. Mortality appeared higher in most groups exposed on day 11 than on day 4, suggesting that on day 11 the extensive chorioallantoic vascular network permitted greater uptake of chemical. Only 24-60% of the embryos survived to hatch at exposure concentrations of 202, 269, and 454 g/L, PC when treated on incubation day 11. At higher concentrations including 681, 956, and 1,211 g/L PC, the compound did not completely dissolve in water and clumped on eggshells, resulting in greater hatching success. Exposures to SE at 100 g/L on incubation day 11 did not significantly affect hatching success of embryos but did significantly reduce the percent hematocrit in blood compared with controls. Incubation day 11 exposure to 202 and 1,211 g/L PC led to a significant increase in plasma aspartate aminotransferase, and day 4 exposure to 1,211 g/L PC resulted in a significant increase in alanine aminotransferase. In addition to elevated liver enzymes, these treatments resulted in a decrease in the number of hepatocyte profiles (1,211 g/L PC at day 4 and day 11) and an increase in hepatocyte size (202 and 1,211 g/L PC at day 11) in hatchlings. A combination of SE and PC was synergistic (202 g/L PC and 50 g/L SE) at day 11 of incubation with respect to decreased hatching success and reduced bone lengths. However, lower concentrations of SE (10 g/L or 30 g/L) combined with 202 g/L of PC appeared antagonistic. This may be due to SE, as a surfactant, altering the ability of PC to penetrate the egg. Our results show fewer adverse effects following exposure to SE than to PC; therefore application of SE may be less harmful to breeding bird populations.

Variability of methacholine bronchoprovocation and the effect of inhaled corticosteroids in mild asthma

PubMed Central

Sumino, Kaharu; Sugar, Elizabeth A.; Irvin, Charles G.; Kaminsky, David A.; Shade, Dave; Wei, Christine Y.; Holbrook, Janet T.; Wise, Robert A.; Castro, Mario

2014-01-01

Background The methacholine challenge test quantifies airway hyper-responsiveness, which is measured by the provocative concentration of methacholine causing a 20% decrease in forced expiration volume in 1 second (PC20). The dose–response effect of inhaled corticosteroids (ICS) on PC20 has been inconsistent and within-patient variability of PC20 is not well established. Objectives To determine the effect of high- vs low-dose ICS on PC20 and within-patient variability in those with repeated measurements of PC20. Methods A randomized, double-masked, crossover trial was conducted in patients with asthma on controller medications with PC20 of 8 mg/mL or lower (n = 64) to evaluate the effect of high-dose (1,000 μg/d) vs low-dose (250 μg/d) fluticasone for 4 weeks on PC20. In addition, the variability of PC20 was assessed in participants who underwent 2 or 3 PC20 measurements on the same dose of ICS (n = 27) over a 4-week interval. Results Because there was a significant period effect, dose comparison of the change in PC20 was assessed in the first treatment period. There was no significant difference in the change in PC20 for high- vs low-dose ICS (39% vs 30% increase, respectively; P = .87). The within- and between-participant variances for log PC20 were 0.84 and 0.96, respectively, with an intra-class correlation of 0.53, and 37% of participants had more than 2 doubling dose changes in PC20 in those with repeated measurements. Conclusion The effect of ICS on PC20 is not dose dependent at fluticasone levels of 250 and 1,000 μg/d. Interpersonal variability for PC20 is large. A lack of precise measurements should be taken into account when interpreting any change in PC20. PMID:24507830

Sex differences in theory-based predictors of leisure time physical activity in a population-based sample of adults with spinal cord injury.

PubMed

Stapleton, Jessie N; Martin Ginis, Kathleen A

2014-09-01

To examine sex differences in theory-based predictors of leisure time physical activity (LTPA) among men and women with spinal cord injury, and secondarily, to identify factors that might explain any sex differences in social cognitions. A secondary analysis of Study of Health and Activity in People with Spinal Cord Injury survey data. Community. Community-dwelling men (n=536) and women (n=164) recruited from 4 rehabilitation and research centers. Not applicable. Subjective norms, attitudes, barrier self-efficacy, perceived controllability (PC), and intentions. Men had stronger PC and barrier self-efficacy than women. Hierarchical regression analyses revealed that social support significantly predicted PC for both sexes, and health, pain, and physical independence also significantly predicted PC for men. Social support, health, and pain significantly predicted barrier self-efficacy for men. Social support was the only significant predictor of barrier self-efficacy for women. Women felt significantly less control over their physical activity behavior and had lower confidence to overcome barriers to physical activity than did men. Although social support predicted PC and barrier self-efficacy in both men and women, men seemed to take additional factors into consideration when formulating their control beliefs for LTPA. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

No positive effect of Acid etching or plasma cleaning on osseointegration of titanium implants in a canine femoral condyle press-fit model.

PubMed

Saksø, H; Jakobsen, T; Saksø, M; Baas, J; Jakobsen, Ss; Soballe, K

2013-01-01

Implant surface treatments that improve early osseointegration may prove useful in long-term survival of uncemented implants. We investigated Acid Etching and Plasma Cleaning on titanium implants. In a randomized, paired animal study, four porous coated Ti implants were inserted into the femurs of each of ten dogs. PC (Porous Coating; control)PC+PSHA (Plasma Sprayed Hydroxyapatite; positive control)PC+ET (Acid Etch)PC+ET+PLCN (Plasma Cleaning) After four weeks mechanical fixation was evaluated by push-out test and osseointegration by histomorphometry. The PSHA-coated implants were better osseointegrated than the three other groups on outer surface implant porosity (p<0.05) while there was no statistical difference in deep surface implant porosity when compared with nontreated implant. Within the deep surface implant porosity, there was more newly formed bone in the control group compared to the ET and ET+PCLN groups (p<0.05). In all compared groups, there was no statistical difference in any biomechanical parameter. In terms of osseointegration on outer surface implant porosity PC+PSHA was superior to the other three groups. Neither the acid etching nor the plasma cleaning offered any advantage in terms of implant osseointegration. There was no statistical difference in any of the biomechanical parameters among all groups in the press-fit model at 4 weeks of evaluation time.

Elevated Choline-Containing Compound Levels in Rapid Cycling Bipolar Disorder.

PubMed

Cao, Bo; Stanley, Jeffrey A; Passos, Ives Cavalcante; Mwangi, Benson; Selvaraj, Sudhakar; Zunta-Soares, Giovana B; Soares, Jair C

2017-10-01

Previous studies have found increased levels of choline-containing compounds (ie, glycerophosphocholine plus phosphocholine (GPC+PC)) in bipolar disorder using in vivo proton magnetic resonance spectroscopy ( 1 H MRS), especially in bipolar I disorder (BD-I). Increased levels of GPC+PC suggest alterations in the membrane phospholipids metabolism in bipolar disorder. Rapid cycling (RC) bipolar disorder is considered as a severe course of bipolar disorder, but it is unclear whether rapid cycling bipolar disorder is linked to highly altered membrane phospholipid metabolism. The purpose of this study was to investigate whether the regional extent of elevated GPC+PC were greater in BD-I patients with rapid cycling compared to BD-I patients without rapid cycling and healthy controls. Using a multi-voxel 1 H MRS approach at 3 Tesla with high spatial resolution and absolute quantification, GPC+PC levels from the anterior cingulate cortex (ACC), caudate and putamen of 16 RC BD-I, 34 non-RC BD-I and 44 healthy controls were assessed. We found significantly elevated GPC+PC levels in ACC, putamen and caudate of RC BD-I patients compared to healthy controls (P<0.005) and in ACC compared to non-RC BD-I patients (P<0.05). These results suggest greater alteration of membrane phospholipid metabolisms in rapid cycling BD-I compared to non-rapid-cycling BD-I.

Identification of viral infections in the prostate and evaluation of their association with cancer

PubMed Central

2010-01-01

Background Several viruses with known oncogenic potential infect prostate tissue, among these are the polyomaviruses BKV, JCV, and SV40; human papillomaviruses (HPVs), and human cytomegalovirus (HCMV) infections. Recently, the Xenotropic Murine Leukemia Virus-related gammaretrovirus (XMRV) was identified in prostate tissue with a high prevalence observed in prostate cancer (PC) patients homozygous for the glutamine variant of the RNASEL protein (462Q/Q). Association studies with the R462Q allele and non-XMRV viruses have not been reported. We assessed associations between prostate cancer, prostate viral infections, and the RNASEL 462Q allele in Mexican cancer patients and controls. Methods 130 subjects (55 prostate cancer cases and 75 controls) were enrolled in the study. DNA and RNA isolated from prostate tissues were screened for the presence of viral genomes. Genotyping of the RNASEL R462Q variant was performed by Taqman method. Results R/R, R/Q, and Q/Q frequencies for R462Q were 0.62, 0.38, and 0.0 for PC cases and 0.69, 0.24, and 0.07 for controls, respectively. HPV sequences were detected in 11 (20.0%) cases and 4 (5.3%) controls. XMRV and HCMV infections were detected in one and six control samples, respectively. The risk of PC was significantly increased (Odds Ratio = 3.98; 95% CI: 1.17-13.56, p = 0.027) by infection of the prostatic tissue with HPV. BKV, JCV, and SV40 sequences were not detected in any of the tissue samples examined. Conclusions We report a positive association between PC and HPV infection. The 462Q/Q RNASEL genotype was not represented in our PC cases; thus, its interaction with prostate viral infections and cancer could not be evaluated. PMID:20576103

Stimulation of surfactant phospholipid biosynthesis in the lungs of rats treated with silica.

PubMed Central

Miller, B E; Hook, G E

1988-01-01

The effects of intratracheally instilled silica (10 mg/rat) on the biosynthesis of surfactant phospholipids was investigated in the lungs of rats. The sizes of the intracellular and extracellular pools of surfactant phospholipids were measured 7, 14 and 28 days after silica exposure. The ability of lung slices to incorporate [14C]choline and [3H]palmitate into surfactant phosphatidylcholine (PC) and disaturated phosphatidylcholine (DSPC) was also investigated. Both intra- and extra-cellular pools of surfactant phospholipids were increased by silica treatment. The intracellular pool increased linearly over the 28-day time period, ultimately reaching a size 62-fold greater than controls. The extracellular pool also increased, but showed a pattern different from that of the intracellular pool. The extracellular pool increased non-linearly up to 14 days, and then declined. At its maximum, the extracellular pool was increased 16-fold over the control. The ability of lung slices to incorporate phospholipid precursors into surfactant-associated PC and DSPC was elevated at all time periods. The rate of incorporation of [14C]choline into surfactant PC and DSPC was maximal at 14 days and was nearly 3-fold greater than the rate in controls. The rate of incorporation of [3H]palmitate was also maximal at 14 days, approx. 5-fold above controls for PC and 3-fold for DSPC. At this same time point, the microsomal activity of cholinephosphate cytidylyltransferase was increased 4.5-fold above controls, but cytosolic activity was not significantly affected by silica treatment. These data indicate that biosynthesis of surfactant PC is elevated after treatment of lungs with silica and that this increased biosynthesis probably underlies the expansion of the intra- and extra-cellular pools of surfactant phospholipids. PMID:2845927

Calidifontibacter indicus gen. nov., sp. nov., a member of the family Dermacoccaceae isolated from a hot spring, and emended description of the family Dermacoccaceae.

PubMed

Ruckmani, Arunachalam; Kaur, Ishwinder; Schumann, Peter; Klenk, Hans-Peter; Mayilraj, Shanmugam

2011-10-01

During the course of a study on the bacterial diversity in Western Ghats, India, an actinobacterial strain, designated PC IW02(T), was isolated and characterized by a polyphasic taxonomic approach. Strain PC IW02(T) was a non-motile, Gram-positive, short rod that formed creamish white to yellow coloured colonies. 16S rRNA gene sequence analysis showed that the novel strain showed highest sequence similarity with type strains of members of the genus Dermacoccus: Dermacoccus barathri (96.6 %), Dermacoccus profundi (96.5 %), Dermacoccus abyssi (96.4 %) and Dermacoccus nishinomiyaensis (95.9 %). The phylogenetic tree suggested that strain PC IW02(T) could represent a member of a new genus of the family Dermacoccaceae with the genus Demetria as closest clade. Pairwise sequence alignment with Demetria terragena HKI 0089(T) and Kytococcus sedentarius DSM 20547(T) showed similarities of 94.2 and 93.7 %, respectively. Strain PC IW02(T) had MK-8(H(4)) as the major menaquinone. The major fatty acids were iso-C(16 : 0) (43.4 %), iso-C(16 : 1) H (17.2 %) and anteiso-C(17 : 0) (9.9 %). The diagnostic cell-wall amino acid at position 3 of the peptide subunit was lysine; the interpeptide bridge consisted of Gly-Ser-Asp. The polar lipids present were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides and phosphatidylserine, along with two unknown phospholipids. The genomic DNA G+C content of the isolate was 77 mol%. On the basis of phenotypic characteristics, including chemotaxonomic data, and 16S rRNA gene sequence similarities, strain PC IW02(T) represents a novel species in a new genus of the family Dermacoccaceae for which the name Calidifontibacter indicus gen. nov., sp. nov. is proposed. The type strain of Calidifontibacter indicus is PC IW02(T) ( = MTCC 8338(T) = DSM 22967(T) = JCM 16038(T)). An emended description of the family Dermacoccaceae is provided.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwon, Jungmi; Tamura, Motohide; Hough, James H.

Near-infrared imaging polarimetry in the J , H , and K{sub s} bands was carried out for GGD 27 in the dark cloud Lynds 291. Details of an infrared reflection nebula associated with the optical nebulosity GGD 27 and the infrared nebula GGD 27 IRS are presented. Aperture photometry of 1263 point-like sources, detected in all three bands, was used to classify them based on a color–color diagram, and the linear polarization of several hundred sources was determined, with the latter used to map the magnetic field structure around GGD 27. This field, around GGD 27 IRS, appears to bemore » associated with the extended CO outflow of IRAS 18162–2048; however, there are partly distorted or bent components in the field. The Chandrasekhar–Fermi method gives an estimate of the magnetic field strength as ∼90 μ G. A region associated with GGD 27 IRS is discovered to have a circular polarization in the range of ∼2%–11% in the K{sub s} band. The circular polarization has an asymmetric positive/negative pattern and extends out to ∼ 120″ or 1.0 pc. The circular and linear polarization patterns are explained as resulting from a combination of dense inner and fainter outer lobes, suggesting episodic outflow.« less

A relativistic neutron fireball from a supernova explosion as a possible source of chiral influence.

PubMed

Gusev, G A; Saito, T; Tsarev, V A; Uryson, A V

2007-06-01

We elaborate on a previously proposed idea that polarized electrons produced from neutrons, released in a supernova (SN) explosion, can cause chiral dissymmetry of molecules in interstellar gas-dust clouds. A specific physical mechanism of a relativistic neutron fireball with Lorentz factor of the order of 100 is assumed for propelling a great number of free neutrons outside the dense SN shell. A relativistic chiral electron-proton plasma, produced from neutron decays, is slowed down owing to collective effects in the interstellar plasma. As collective effects do not involve the particle spin, the electrons can carry their helicities to the cloud. The estimates show high chiral efficiency of such electrons. In addition to this mechanism, production of circularly polarized ultraviolet photons through polarized-electron bremsstrahlung at an early stage of the fireball evolution is considered. It is shown that these photons can escape from the fireball plasma. However, for an average density of neutrals in the interstellar medium of the order of 0.2 cm(-3) and at distances of the order of 10 pc from the SN, these photons will be absorbed with a factor of about 10(-7) due to the photoeffect. In this case, their chiral efficiency will be about five orders of magnitude less than that for polarized electrons.

Carbohydrate intake, glycemic index and prostate cancer risk.

PubMed

Vidal, Adriana C; Williams, Christina D; Allott, Emma H; Howard, Lauren E; Grant, Delores J; McPhail, Megan; Sourbeer, Katharine N; Hwa, Lin Pao; Boffetta, Paolo; Hoyo, Cathrine; Freedland, Stephen J

2015-03-01

Reported associations between dietary carbohydrate and prostate cancer (PC) risk are poorly characterized by race. We analyzed the association between carbohydrate intake, glycemic index (GI), and PC risk in a study of white (N = 262) and black (N = 168) veterans at the Durham VA Hospital. Cases were 156 men with biopsy-confirmed PC and controls (N = 274) had a PSA test but were not recommended for biopsy. Diet was assessed before biopsy with a self-administered food frequency questionnaire. Logistic regression models were used to estimate PC risk. In multivariable analyzes, higher carbohydrate intake, measured as percent of energy from carbohydrates, was associated with reduced PC risk (3rd vs. 1st tertile, OR = 0.41, 95% CI 0.21-0.81, P = 0.010), though this only reached significance in white men (p-trend = 0.029). GI was unrelated to PC risk among all men, but suggestively linked with reduced PC risk in white men (p-trend = 0.066) and increased PC risk in black men (p-trend = 0.172), however, the associations were not significant. Fiber intake was not associated with PC risk (all p-trends > 0.55). Higher carbohydrate intake was associated with reduced risk of high-grade (p-trend = 0.016), but not low-grade PC (p-trend = 0.593). Higher carbohydrate intake may be associated with reduced risk of overall and high-grade PC. Future larger studies are needed to confirm these findings. © 2014 Wiley Periodicals, Inc.

Carbohydrate intake, glycemic index and prostate cancer risk

PubMed Central

Vidal, Adriana C.; Williams, Christina D.; Allott, Emma H.; Howard, Lauren E.; Grant, Delores J.; McPhail, Megan; Sourbeer, Katharine N.; Pao-Hwa, Lin; Boffetta, Paolo; Hoyo, Cathrine; Freedland, Stephen J.

2014-01-01

BACKGROUND Reported associations between dietary carbohydrate and prostate cancer (PC) risk are poorly characterized by race. METHODS We analyzed the association between carbohydrate intake, glycemic index (GI), and PC risk in a study of white (N=262) and black (N=168) veterans at the Durham VA Hospital. Cases were 156 men with biopsy-confirmed PC and controls (N=274) had a PSA test but were not recommended for biopsy. Diet was assessed before biopsy with a self-administered food frequency questionnaire. Logistic regression models were used to estimate PC risk. RESULTS In multivariable analyses, higher carbohydrate intake, measured as percent of energy from carbohydrates, was associated with reduced PC risk (3rd vs. 1st tertile, OR=0.41, 95%CI 0.21–0.81, p=0.010), though this only reached significance in white men (p-trend=0.029). GI was unrelated to PC risk among all men, but suggestively linked with reduced PC risk in white men (p-trend=0.066) and increased PC risk in black men (p-trend=0.172), however the associations were not significant. Fiber intake was not associated with PC risk (all p-trends >0.55). Higher carbohydrate intake was associated with reduced risk of high-grade (p-trend=0.016), but not low-grade PC (p-trend=0.593). CONCLUSIONS Higher carbohydrate intake may be associated with reduced risk of overall and high-grade PC. Future larger studies are needed to confirm these findings. PMID:25417840

Temperature-assisted morphological transition in CuPc thin films

NASA Astrophysics Data System (ADS)

Bae, Yu Jeong; Pham, Thi Kim Hang; Kim, Tae Hee

2016-05-01

Ex-situ and in-situ morphological analyses were performed for Cu-phthalocyanine (CuPc) organic semiconductor films by using atomic force microscopy (AFM) and reflection high-energy electron diffraction (RHEED). The focus was the effects of post-annealing on the structural characteristics of CuPc films grown on MgO(001) layers by using an ultra-high-vacuum thermal evaporator. Sphere-to-nanofibril and 2-D to 3-D morphological transitions were observed with increasing CuPc thickness beyond 3 nm. The surface morphology and the crystallinity were drastically improved after an additional cooling of the post-annealed CuPc films thinner than 3 nm. Our results highlight that molecular orientation and structural ordering can be effectively controlled by using different temperature treatments and a proper combination of material, film thickness, and substrate.

Cost-effectiveness analysis of pharmaceutical care for hypertensive patients from the perspective of the public health system in Brazil.

PubMed

Cazarim, Maurílio de Souza; Pereira, Leonardo Régis Leira

2018-01-01

Only 20% of patients with systemic arterial hypertension (SAH) have blood pressure within recommended parameters. SAH has been the main risk factor for morbidity and mortality of cardiovascular diseases, which affects the burden of the Public Health System (PHS). Some studies have shown the effectiveness of Pharmaceutical Care (PC) in the care of hypertensive patients. To perform a cost-effectiveness analysis to compare SAH treatment with PC management and conventional treatment for hypertensive patients offered by the PHS. A cost-effectiveness study nested to a quasi-experimental study was conducted, in which 104 hypertensive patients were followed up in a PC program. Blood pressure control was considered as the outcome for the economic analysis and the costs were direct and non-direct medical costs. PC was dominant for two years in the post-PC period compared with the pre-PC year. The mean cost effectiveness ratio (CER) for the CERPre-PC, CERPC, and CERPost-PC periods were: US$ 364.65, US$ 415.39, and US$ 231.14 respectively. The incremental cost effectiveness ratio (ICER) analysis presented ICER of US$ 478.41 in the PC period and US$ 42.95 in the post PC period. Monte Carlo sensitivity analysis presented mean ICERPC and ICERPost-PC equal to US$ 605.09 and US$ 128.03, reaching US$ 1,725.00 and US$ 740.00 respectively. Even for the highest ICER, the values were below the cost effectiveness threshold, which means that PC was a cost effective strategy for the care of hypertensive patients in the PHS.

Altered molecular specificity of surfactant phosphatidycholine synthesis in patients with acute respiratory distress syndrome.

PubMed

Dushianthan, Ahilanandan; Goss, Victoria; Cusack, Rebecca; Grocott, Michael P W; Postle, Anthony D

2014-11-07

Acute respiratory distress syndrome (ARDS) is a life-threatening critical illness, characterised by qualitative and quantitative surfactant compositional changes associated with premature airway collapse, gas-exchange abnormalities and acute hypoxic respiratory failure. The underlying mechanisms for this dysregulation in surfactant metabolisms are not fully explored. Lack of therapeutic benefits from clinical trials, highlight the importance of detailed in-vivo analysis and characterisation of ARDS patients according to patterns of surfactant synthesis and metabolism. Ten patients with moderate to severe ARDS were recruited. Most (90%) suffered from pneumonia. They had an infusion of methyl-D9-choline chloride and small volume bronchoalveolar lavage fluid (BALF) was obtained at 0,6,12,24,48,72 and 96 hours. Controls were healthy volunteers, who had BALF at 24 and 48 hours after methyl-D9-choline infusion. Compositional analysis and enrichment patterns of stable isotope labelling of surfactant phosphatidylcholine (PC) was determined by electrospray ionisation mass spectrometry. BALF of patients with ARDS consisted of diminished total PC and fractional PC16:0/16:0 concentrations compared to healthy controls. Compositional analysis revealed, reductions in fractional compositions of saturated PC species with elevated levels of longer acyl chain unsaturated PC species. Molecular specificity of newly synthesised PC fraction showed time course variation, with lower PC16:0/16:0 composition at earlier time points, but achieved near equilibrium with endogenous composition at 48 hours after methyl-D9-choline infusion. The enrichment of methyl-D9-choline into surfactant total PC is nearly doubled in patients, with considerable variation between individuals. This study demonstrate significant alterations in composition and kinetics of surfactant PC extracted from ARDS patients. This novel approach may facilitate biochemical phenotyping of ARDS patients according to surfactant synthesis and metabolism, enabling individualised treatment approaches for the management of ARDS patients in the future.

Ion flux oscillations associated with a radially polarized transverse Pc 5 magnetic pulsation

NASA Technical Reports Server (NTRS)

Takahashi, K.; Mcentire, R. W.; Lui, A. T. Y.; Potemra, T. A.

1990-01-01

The AMPTE CCE spacecraft observed a transverse Pc 5 magnetic pulsation (period of about 200 s) at 2155-2310 UT on November 20, 1985, at a radial distance of 5.7 - 7.0 earth radii, at a magnetic latitude of 1.2 - 19 deg, and near 1300 magnetic local time. The magnetic pulsation exhibits properties consistent with a standing Alfven wave with a second-harmonic standing structure along the ambient magnetic field. The amplitude and the phase of the flux pulsation are found to be a function of the particle detector look direction and the particle energy. The observed energy dependence of the shift is interpreted as the result of a drift-bounce resonance of the ions with the wave. From this interpretation it follows that the wave propagated westward with an azimuthal wave number of approximately 100. Thus the study demonstrates that particle data can be useful for determining the spatial structure of some types of ULF waves.

Local Circumnuclear Magnetar Solution to Extragalactic Fast Radio Bursts

NASA Astrophysics Data System (ADS)

Pen, Ue-Li; Connor, Liam

2015-07-01

We synthesize the known information about fast radio bursts (FRBs) and radio magnetars, and describe an allowed origin near nuclei of external, but non-cosmological, galaxies. This places them at z\\ll 1, within a few hundred megaparsecs. In this scenario, the high dispersion measure (DM) is dominated by the environment of the FRB, modeled on the known properties of the Milky Way center, whose innermost 100 pc provides 1000 pc cm-3. A radio loud magnetar is known to exist in our galactic center, within ˜2 arcsec of Sgr A*. Based on the polarization, DM, and scattering properties of this known magnetar, we extrapolate its properties to those of Crab-like giant pulses and SGR flares and point out their consistency with observed FRBs. We conclude that galactic center magnetars could be the source of FRBs. This scenario is readily testable with very long baseline interferometry measurements as well as with flux count statistics from large surveys such as CHIME or UTMOST.

A Cost Effective System Design Approach for Critical Space Systems

NASA Technical Reports Server (NTRS)

Abbott, Larry Wayne; Cox, Gary; Nguyen, Hai

2000-01-01

NASA-JSC required an avionics platform capable of serving a wide range of applications in a cost-effective manner. In part, making the avionics platform cost effective means adhering to open standards and supporting the integration of COTS products with custom products. Inherently, operation in space requires low power, mass, and volume while retaining high performance, reconfigurability, scalability, and upgradability. The Universal Mini-Controller project is based on a modified PC/104-Plus architecture while maintaining full compatibility with standard COTS PC/104 products. The architecture consists of a library of building block modules, which can be mixed and matched to meet a specific application. A set of NASA developed core building blocks, processor card, analog input/output card, and a Mil-Std-1553 card, have been constructed to meet critical functions and unique interfaces. The design for the processor card is based on the PowerPC architecture. This architecture provides an excellent balance between power consumption and performance, and has an upgrade path to the forthcoming radiation hardened PowerPC processor. The processor card, which makes extensive use of surface mount technology, has a 166 MHz PowerPC 603e processor, 32 Mbytes of error detected and corrected RAM, 8 Mbytes of Flash, and I Mbytes of EPROM, on a single PC/104-Plus card. Similar densities have been achieved with the quad channel Mil-Std-1553 card and the analog input/output cards. The power management built into the processor and its peripheral chip allows the power and performance of the system to be adjusted to meet the requirements of the application, allowing another dimension to the flexibility of the Universal Mini-Controller. Unique mechanical packaging allows the Universal Mini-Controller to accommodate standard COTS and custom oversized PC/104-Plus cards. This mechanical packaging also provides thermal management via conductive cooling of COTS boards, which are typically designed for convection cooling methods.

Interferon-gamma +874 T/A and interleukin-10 -1082 A/G single nucleotide polymorphism in Egyptian children with tuberculosis.

PubMed

Mosaad, Y M; Soliman, O E; Tawhid, Z E; Sherif, D M

2010-10-01

The aim was to investigate the association of interferon-gamma (IFN-γ) +874 T/A and interleukin-10 (IL-10)-1082 A/G single nucleotide polymorphisms with tuberculous infection and post-BCG lymphadenitis in Egyptian children. IFN-γ +874 T/A and IL-10 -1082 A/G polymorphism detection by amplification refractory mutation system technique was carried out for 110 patients with TB, 40 patients with post-BCG lymphadenitis and 118 healthy controls. IFN-γ +874 A allele was higher in TB and post-BCG patients than those in healthy controls (Pc=0.006 and 0.002, respectively). IFN-γ +874 genotype AA was significantly higher in patients with TB than that in control (Pc=0.015), in extrapulmonary than patients with pulmonary TB (PTB) (Pc=0.009), and young children with TB below 5 years (Pc=0.024). No statistically significant differences were observed between patients with TB and controls for the frequency of IL-10(-1082) alleles or genotypes (P>0.05); however, a statistically significant difference in the frequency of IL-10 (-1082) GG genotype was found between patients with pulmonary and extrapulmonary TB (Pc=0.003). Low producer IFN-γ +874 A/A genotype is associated with post-BCG lymphadenitis and TB disease especially in younger children below 5 years. IL-10-1082 G/G genotype did not exhibit significant association except for increased GG frequency in PTB. Both cytokine polymorphisms have no relation to tuberculin reaction in patients with TB. © 2010 The Authors. Scandinavian Journal of Immunology © 2010 Blackwell Publishing Ltd.

The research on visual industrial robot which adopts fuzzy PID control algorithm

NASA Astrophysics Data System (ADS)

Feng, Yifei; Lu, Guoping; Yue, Lulin; Jiang, Weifeng; Zhang, Ye

2017-03-01

The control system of six degrees of freedom visual industrial robot based on the control mode of multi-axis motion control cards and PC was researched. For the variable, non-linear characteristics of industrial robot`s servo system, adaptive fuzzy PID controller was adopted. It achieved better control effort. In the vision system, a CCD camera was used to acquire signals and send them to video processing card. After processing, PC controls the six joints` motion by motion control cards. By experiment, manipulator can operate with machine tool and vision system to realize the function of grasp, process and verify. It has influence on the manufacturing of the industrial robot.

Stroop proactive control and task conflict are modulated by concurrent working memory load.

PubMed

Kalanthroff, Eyal; Avnit, Amir; Henik, Avishai; Davelaar, Eddy J; Usher, Marius

2015-06-01

Performance on the Stroop task reflects two types of conflict-informational (between the incongruent word and font color) and task (between the contextually relevant color-naming task and the irrelevant, but automatic, word-reading task). According to the dual mechanisms of control theory (DMC; Braver, 2012), variability in Stroop performance can result from variability in the deployment of a proactive task-demand control mechanism. Previous research has shown that when proactive control (PC) is diminished, both increased Stroop interference and a reversed Stroop facilitation (RF) are observed. Although the current DMC model accounts for the former effect, it does not predict the observed RF, which is considered to be behavioral evidence for task conflict in the Stroop task. Here we expanded the DMC model to account for Stroop RF. Assuming that a concurrent working memory (WM) task reduces PC, we predicted both increased interference and an RF. Nineteen participants performed a standard Stroop task combined with a concurrent n-back task, which was aimed at reducing available WM resources, and thus overloading PC. Although the results indicated common Stroop interference and facilitation in the low-load condition (zero-back), in the high-load condition (two-back), both increased Stroop interference and RF were observed, consistent with the model's prediction. These findings indicate that PC is modulated by concurrent WM load and serves as a common control mechanism for both informational and task Stroop conflicts.

Metabolic syndrome in patients with prostate cancer undergoing androgen suppression.

PubMed

Morote, J; Ropero, J; Planas, J; Celma, A; Placer, J; Ferrer, R; de Torres, I

2014-06-01

Cardiovascular mortality is the leading cause of death in patients with prostate cancer (PC), metabolic syndrome (MS) being related to it. The main objective of this study was to determine the prevalence of MS in patients with CP undergoing androgen suppression (AS). We performed a retrospective study of cases and controls that included 159 patients. The study group was made up of 53 patients with PC undergoing SA for a period exceeding 12 months. The control group was formed by 53 patients with PC at the time of diagnosis and 53 patients with negative prostate biopsy. All patients were evaluated for presence of MS according to NCEP-ATPIII criteria. Prevalence of MS in patients without PC was 32.1% and in those with non-treated PC 35.8%, P = .324. In patients with PC undergoing AS, prevalence of MS was 50.9%, P < .001. When AS duration was less than 36 months, prevalence of MS was 44.0% and when greater than 36 months 57.1%, P < .001. Waist circumference and hyperglycemia were the two MS components that significantly increased. AS and its duration were independent predictors factors for the development of MS. Continuous AS therapy increases the prevalence of MS and especially waist circumference and hyperglycemia. Development of MS increases according to AS duration. Copyright © 2013 AEU. Published by Elsevier Espana. All rights reserved.

Enhancer of polycomb coordinates multiple signaling pathways to promote both cyst and germline stem cell differentiation in the Drosophila adult testis

PubMed Central

Feng, Lijuan; Shi, Zhen; Chen, Xin

2017-01-01

Stem cells reside in a particular microenvironment known as a niche. The interaction between extrinsic cues originating from the niche and intrinsic factors in stem cells determines their identity and activity. Maintenance of stem cell identity and stem cell self-renewal are known to be controlled by chromatin factors. Herein, we use the Drosophila adult testis which has two adult stem cell lineages, the germline stem cell (GSC) lineage and the cyst stem cell (CySC) lineage, to study how chromatin factors regulate stem cell differentiation. We find that the chromatin factor Enhancer of Polycomb [E(Pc)] acts in the CySC lineage to negatively control transcription of genes associated with multiple signaling pathways, including JAK-STAT and EGF, to promote cellular differentiation in the CySC lineage. E(Pc) also has a non-cell-autonomous role in regulating GSC lineage differentiation. When E(Pc) is specifically inactivated in the CySC lineage, defects occur in both germ cell differentiation and maintenance of germline identity. Furthermore, compromising Tip60 histone acetyltransferase activity in the CySC lineage recapitulates loss-of-function phenotypes of E(Pc), suggesting that Tip60 and E(Pc) act together, consistent with published biochemical data. In summary, our results demonstrate that E(Pc) plays a central role in coordinating differentiation between the two adult stem cell lineages in Drosophila testes. PMID:28196077

Active Galaxy Unification in the Era of X-Ray Polarimetry

NASA Technical Reports Server (NTRS)

Dorodnitsyn, A.; Kallman, T.

2010-01-01

Active galactic nuclei (AGNs), Seyfert galaxies, and quasars are powered by luminous accretion and often accompanied by winds that are powerful enough to affect the AGN mass budget, and whose observational appearance bears an imprint of processes that are happening within the central parsec around the black hole (BH). One example of such a wind is the partially ionized gas responsible for X-ray and UV absorption (warm absorbers). Here, we show that such gas will have a distinct signature when viewed in polarized X-rays. Observations of such polarization can test models for the geometry of the flow and the gas responsible for launching and collimating it. We present calculations that show that the polarization depends on the hydrodynamics of the flow, the quantum mechanics of resonance-line scattering, and the transfer of polarized X-ray light in the highly ionized moving gas. The results emphasize the three-dimensional nature of the wind for modeling spectra. We show that the polarization in the 0.1-10 keV energy range is dominated by the effects of resonance lines. We predict a 5%-25% X-ray polarization signature of type-2 objects in this energy range. These results are generalized to flows that originate from a cold torus-like structure, located approximately 1 pc from the BH, which wraps the BH and is ultimately responsible for the apparent dichotomy between type 1 and type 2 AGNs. Such signals will be detectable by future dedicated X-ray polarimetry space missions, such as the NASA Gravity and Extreme Magnetism Small Explorer SMEX, "GEMS" Swank et al. (2008).

Para-hydrogen induced polarization without incorporation of para-hydrogen into the analyte.

PubMed

Atkinson, Kevin D; Cowley, Michael J; Duckett, Simon B; Elliott, Paul I P; Green, Gary G R; López-Serrano, Joaquín; Khazal, Iman G; Whitwood, Adrian C

2009-01-19

The cationic iridium complexes [Ir(COD)(PR3)2]BF4 (1a-c) (a, R = Ph; b, R = p-tolyl; c, R = p-C6H4-OMe) react with parahydrogen in the presence of pyridine to give trans, cis, cis-[Ir(PR3)2(py)2(H)2]+ (2a-c) and small amounts of fac, cis-[Ir(PR3)(py)3(H)2]+ (3a-c), each of which exhibit polarized hydride resonances due to the magnetic inequivalence associated with the resultant AA"XX" spin system when 15N-labeled pyridine is employed. The pyridine ligands in 2 are labile, exchanging slowly into free pyridine with a rate constant of 0.4 s(-1) for 2a at 335 K in a dissociative process where DeltaH(double dagger) = 134 +/- 1 kJ mol(-1) and DeltaS(double dagger) = 151 +/- 5 J mol(-1) K(-1). Pyridine ligand exchange in 2 proves to be slower than that determined for 3. Parahydrogen induced polarization (PHIP) based on the hydride ligands of 2 and 3 is transferred efficiently to the 15N nuclei of the bound pyridine ligand by suitable insensitive-nuclei-enhanced-by-polarization-transfer (INEPT) based procedures. Related methods are then used to facilitate the sensitization of the free pyridine 15N signal by a factor of 120-fold through ligand exchange even though this substrate does not contain parahydrogen. This therefore corresponds to the successful polarization of an analyte by parahydrogen induced polarization methods without the need for the actual chemical incorporation of any parahydrogen derived nuclei into it.

Universal control and measuring system for modern classic and amorphous magnetic materials single/on-line strip testers

NASA Astrophysics Data System (ADS)

Zemánek, Ivan; Havlíček, Václav

2006-09-01

A new universal control and measuring system for classic and amorphous soft magnetic materials single/on-line strip testing has been developed at the Czech Technical University in Prague. The measuring system allows to measure magnetization characteristic and specific power losses of different tested materials (strips) at AC magnetization of arbitrary magnetic flux density waveform at wide range of frequencies 20 Hz-20 kHz. The measuring system can be used for both single strip testing in laboratories and on-line strip testing during the production process. The measuring system is controlled by two-stage master-slave control system consisting of the external PC (master) completed by three special A/D measuring plug-in boards, and local executing control unit (slave) with one-chip microprocessor 8051, connected with PC by the RS232 serial line. The "user friendly" powerful control software implemented on the PC and the effective program code for the microprocessor give possibility for full automatic measurement with high measuring power and high measuring accuracy.

Does Pre-Cooling With Whole-Body Immersion Affect Thermal Sensation or Perceived Exertion?: A Critically-Appraised Topic.

PubMed

Wohlfert, Timothy M; Miller, Kevin C

2018-02-21

Clinical Scenario: Exertional heat stroke (EHS) is a potentially deadly heat illness and poses a significant health risk to athletes; EHS survival rates are near 100% if properly recognized and treated. 1 Whole body cold water immersion (CWI) is the most effective method of lowering body core temperature. 2 Precooling (PC) with CWI before exercise may prevent severe hyperthermia and/or EHS by increasing the body's overall heat-storage capacity. 3 However, PC may also alter athletes' perception of how hot they feel or how hard they are exercising. Consequently, they may be unable to accurately perceive their body core temperature or how hard they are working which may predispose them to severe hyperthermia or EHS. Does PC with whole-body CWI affect thermal sensation (TS) or rating of perceived exertion (RPE) during exercise in the heat? In four studies, 4-7 RPE during exercise ranged from 12 ± 2 to 20 ± 3 with no clinically meaningful differences between PC and control trials. Thermal sensation scores ranged from 2 ± 1 to 8 ± 0.5 in control trials and from 2 ± 1 to 7.5 ± 0.5 during PC trials. Clinical Bottom Line: Precooling did not cause clinically-meaningful differences in RPE or TS during exercise. It is unlikely PC would predispose athletes to EHS by altering perceptions of exercise intensity or body core temperature. Strength of Recommendation: None of the reviewed studies 4-7 (all level 2 studies with PEDro scores ≥5) suggest PC with CWI influences RPE or TS in exercising males.

Distributed cerebellar plasticity implements adaptable gain control in a manipulation task: a closed-loop robotic simulation

PubMed Central

Garrido, Jesús A.; Luque, Niceto R.; D'Angelo, Egidio; Ros, Eduardo

2013-01-01

Adaptable gain regulation is at the core of the forward controller operation performed by the cerebro-cerebellar loops and it allows the intensity of motor acts to be finely tuned in a predictive manner. In order to learn and store information about body-object dynamics and to generate an internal model of movement, the cerebellum is thought to employ long-term synaptic plasticity. LTD at the PF-PC synapse has classically been assumed to subserve this function (Marr, 1969). However, this plasticity alone cannot account for the broad dynamic ranges and time scales of cerebellar adaptation. We therefore tested the role of plasticity distributed over multiple synaptic sites (Hansel et al., 2001; Gao et al., 2012) by generating an analog cerebellar model embedded into a control loop connected to a robotic simulator. The robot used a three-joint arm and performed repetitive fast manipulations with different masses along an 8-shape trajectory. In accordance with biological evidence, the cerebellum model was endowed with both LTD and LTP at the PF-PC, MF-DCN and PC-DCN synapses. This resulted in a network scheme whose effectiveness was extended considerably compared to one including just PF-PC synaptic plasticity. Indeed, the system including distributed plasticity reliably self-adapted to manipulate different masses and to learn the arm-object dynamics over a time course that included fast learning and consolidation, along the lines of what has been observed in behavioral tests. In particular, PF-PC plasticity operated as a time correlator between the actual input state and the system error, while MF-DCN and PC-DCN plasticity played a key role in generating the gain controller. This model suggests that distributed synaptic plasticity allows generation of the complex learning properties of the cerebellum. The incorporation of further plasticity mechanisms and of spiking signal processing will allow this concept to be extended in a more realistic computational scenario. PMID:24130518

Effect of high-dose phytase supplementation in broilers from 22 to 42 days post-hatch given diets severely limited in available phosphorus.

PubMed

Taheri, H R; Heidari, A; Shahir, M H

2015-01-01

1. Two trials were conducted from 22 to 42 d post-hatch to evaluate the effectiveness of high concentrations of supplemental phytase in maize-soya bean meal-based diets severely limited in available phosphorus (P). Growth performance, plasma P and tibia ash (TA) were measured. 2. Each trial used 220 21-d-old male broilers in 20 pens with 11 birds per pen. Dietary treatments included a positive control [PC, 4.3 g/kg nonphytate P (NPP)], negative control [NC, 2.3 g/kg NPP (Trial 1) or 1.4 g/kg NPP (Trial 2)] and NC plus 1000, 2000 or 4000 phytase U/kg of the diet. 3. Birds fed on the PC diet had higher average daily gain (ADG), gain to feed ratio (G:F), plasma P (Trials 1 and 2) and TA (Trial 2) than those fed on the NC. 4. In Trial 1, ADG and G:F values of the NC plus 1000, 2000 or 4000 phytase U/kg reached those of the PC. Plasma P values of the NC plus 2000 or 4000 phytase U/kg reached that of the PC. Although TA values of the NC, NC + 1000 or NC + 2000 reached that of the PC, TA of the NC + 4000 was more than that of the PC. 5. In Trial 2, ADG and G:F values of the NC plus 4000 phytase U/kg reached those of the PC; nevertheless, plasma P values of the NC diets did not come up to that of the PC. While TA values of the NC, NC + 1000 or NC + 2000 did not reach that of the PC, TA of the NC + 4000 was greater than that of the PC. 6. Results of this study showed that, in the diets with 2.3 and 1.4 g/kg NPP, respectively, 1000 and 4000 phytase U/kg can be sufficient to obtain a comparable performance in broilers to those given diets adequate in available P.

Polarimetry at millimeter wavelengths with the NIKA camera: calibration and performance

NASA Astrophysics Data System (ADS)

Ritacco, A.; Ponthieu, N.; Catalano, A.; Adam, R.; Ade, P.; André, P.; Beelen, A.; Benoît, A.; Bideaud, A.; Billot, N.; Bourrion, O.; Calvo, M.; Coiffard, G.; Comis, B.; Désert, F.-X.; Doyle, S.; Goupy, J.; Kramer, C.; Leclercq, S.; Macías-Pérez, J. F.; Mauskopf, P.; Maury, A.; Mayet, F.; Monfardini, A.; Pajot, F.; Pascale, E.; Perotto, L.; Pisano, G.; Rebolo-Iglesias, M.; Revéret, V.; Rodriguez, L.; Romero, C.; Ruppin, F.; Savini, G.; Schuster, K.; Sievers, A.; Thum, C.; Triqueneaux, S.; Tucker, C.; Zylka, R.

2017-03-01

Magnetic fields, which play a major role in a large number of astrophysical processes can be traced via observations of dust polarization. In particular, Planck low-resolution observations of dust polarization have demonstrated that Galactic filamentary structures, where star formation takes place, are associated to well organized magnetic fields. A better understanding of this process requires detailed observations of galactic dust polarization on scales of 0.01 to 0.1 pc. Such high-resolution polarization observations can be carried out at the IRAM 30 m telescope using the recently installed NIKA2 camera, which features two frequency bands at 260 and 150 GHz (respectively 1.15 and 2.05 mm), the 260 GHz band being polarization sensitive. NIKA2 so far in commissioning phase, has its focal plane filled with 3300 detectors to cover a Field of View (FoV) of 6.5 arcmin diameter. The NIKA camera, which consisted of two arrays of 132 and 224 Lumped Element Kinetic Inductance Detectors (LEKIDs) and a FWHM (Full-Width-Half-Maximum) of 12 and 18.2 arcsec at 1.15 and 2.05 mm respectively, has been operated at the IRAM 30 m telescope from 2012 to 2015 as a test-bench for NIKA2. NIKA was equipped of a room temperature polarization system (a half wave plate (HWP) and a grid polarizer facing the NIKA cryostat window). The fast and continuous rotation of the HWP permits the quasi simultaneous reconstruction of the three Stokes parameters, I, Q, and U at 150 and 260 GHz. This paper presents the first polarization measurements with KIDs and reports the polarization performance of the NIKA camera and the pertinence of the choice of the polarization setup in the perspective of NIKA2. We describe the polarized data reduction pipeline, specifically developed for this project and how the continuous rotation of the HWP permits to shift the polarized signal far from any low frequency noise. We also present the dedicated algorithm developed to correct systematic leakage effects. We report results on compact and extended sources obtained duringthe February 2015 technical campaign. These results demonstrate a good understanding of polarization systematics and state-of-the-art performance in terms of photometry, polarization degree and polarization angle reconstruction.

Training Pediatric Fellows in Palliative Care: A Pilot Comparison of Simulation Training and Didactic Education.

PubMed

Brock, Katharine E; Cohen, Harvey J; Sourkes, Barbara M; Good, Julie J; Halamek, Louis P

2017-10-01

Pediatric fellows receive little palliative care (PC) education and have few opportunities to practice communication skills. In this pilot study, we assessed (1) the relative effectiveness of simulation-based versus didactic education, (2) communication skill retention, and (3) effect on PC consultation rates. Thirty-five pediatric fellows in cardiology, critical care, hematology/oncology, and neonatology at two institutions enrolled: 17 in the intervention (simulation-based) group (single institution) and 18 in the control (didactic education) group (second institution). Intervention group participants participated in a two-day program over three months (three simulations and videotaped PC panel). Control group participants received written education designed to be similar in content and time. (1) Self-assessment questionnaires were completed at baseline, post-intervention and three months; mean between-group differences for each outcome measure were assessed. (2) External reviewers rated simulation-group encounters on nine communication domains. Within-group changes over time were assessed. (3) The simulation-based site's PC consultations were compared in the six months pre- and post-intervention. Compared to the control group, participants in the intervention group improved in self-efficacy (p = 0.003) and perceived adequacy of medical education (p < 0.001), but not knowledge (p = 0.20). Reviewers noted nonsustained improvement in four domains: relationship building (p = 0.01), opening discussion (p = 0.03), gathering information (p = 0.01), and communicating accurate information (p = 0.04). PC consultation rate increased 64%, an improvement when normalized to average daily census (p = 0.04). This simulation-based curriculum is an effective method for improving PC comfort, education, and consults. More frequent practice is likely needed to lead to sustained improvements in communication competence.

Polarization Control with Piezoelectric and LiNbO3 Transducers

NASA Astrophysics Data System (ADS)

Bradley, E.; Miles, E.; Loginov, B.; Vu, N.

Several Polarization control transducers have appeared on the market, and now automated, endless polarization control systems using these transducers are becoming available. Unfortunately it is not entirely clear what benchmark performance tests a polarization control system must pass, and the polarization disturbances a system must handle are open to some debate. We present quantitative measurements of realistic polarization disturbances and two benchmark tests we have successfully used to evaluate the performance of an automated, endless polarization control system. We use these tests to compare the performance of a system using piezoelectric transducers to that of a system using LiNbO3 transducers.

KSC-98pc1831

NASA Image and Video Library

1998-12-02

KENNEDY SPACE CENTER, FLA. -- Inside the gantry on Pad 17B, Cape Canaveral Air Station, the fairing for the upper stages of the Delta II rocket carrying the Mars Polar Lander waits to be lowered into the white room. The rocket will be used to launch the Mars Polar Lander on Jan. 3, 1999. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. It is the second spacecraft to be launched in a pair of Mars '98 missions. The first is the Mars Climate Orbiter, to be launched aboard a Delta II rocket from Launch Complex 17A in December 1998

KSC-98pc1824

NASA Image and Video Library

1998-12-02

KENNEDY SPACE CENTER, FLA. -- On Pad 17B, Cape Canaveral Air Station, a solid rocket booster is raised to a vertical position for mating with the Delta II rocket carrying the Mars Polar Lander. The rocket will be used to launch the Mars Polar Lander on Jan. 3, 1999. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. It is the second spacecraft to be launched in a pair of Mars '98 missions. The first is the Mars Climate Orbiter, to be launched aboard a Delta II rocket from Launch Complex 17A in December 1998

KSC-98pc1196

NASA Image and Video Library

1998-10-01

KENNEDY SPACE CENTER, FLA. -- At the Shuttle Landing Facility, the Mars Polar Lander is loaded onto a truck after its flight aboard an Air Force C-17 cargo plane that carried it from the Lockheed Martin Astronautics plant in Denver, CO. The lander is being transported to the Spacecraft Assembly and Encapsulation Facility-2(SAEF-2) in the KSC Industrial Area for testing, including a functional test of the science instruments and the basic spacecraft subsystems. The solar-powered spacecraft is designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. The Mars Polar Lander spacecraft is planned for launch from Cape Canaveral Air Station aboard a Delta II rocket on Jan. 3, 1999

KSC-98pc1829

NASA Image and Video Library

1998-12-02

KENNEDY SPACE CENTER, FLA. -- The fairing for the upper stages of the Delta II rocket carrying the Mars Polar Lander is lifted to the top of the gantry on Pad 17B, Cape Canaveral Air Station. The rocket will be used to launch the Mars Polar Lander on Jan. 3, 1999. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. It is the second spacecraft to be launched in a pair of Mars '98 missions. The first is the Mars Climate Orbiter, to be launched aboard a Delta II rocket from Launch Complex 17A in December 1998

KSC-98pc1352

NASA Image and Video Library

1998-10-16

In the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2), the Mars Climate Orbiter (foreground) and the Mars Polar Lander are on display for the media. The scheduled launch date for the Mars Climate Orbiter is Dec. 10, 1998, aboard a Boeing Delta II rocket. It is heading for Mars where it will primarily support its companion Mars Polar Lander spacecraft, planned for launch on Jan. 3, 1999. After that, the Mars Climate Orbiter's instruments will monitor the Martian atmosphere and image the planet's surface on a daily basis for one Martian year (two Earth years). It will observe the appearance and movement of atmospheric dust and water vapor, as well as characterize seasonal changes on the surface. The detailed images of the surface features will provide important clues to the planet's early climate history and give scientists more information about possible liquid water reserves beneath the surface

KSC-98pc1821

NASA Image and Video Library

1998-12-02

KENNEDY SPACE CENTER, FLA. -- On Pad 17B, Cape Canaveral Air Station, workers monitor the solid rocket booster before its being lifted to mate with the Delta II rocket carrying the Mars Polar Lander. The rocket will be used to launch the Mars Polar Lander on Jan. 3, 1999. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. It is the second spacecraft to be launched in a pair of Mars '98 missions. The first is the Mars Climate Orbiter, to be launched aboard a Delta II rocket from Launch Complex 17A in December 1998

KSC-98pc1825

NASA Image and Video Library

1998-12-02

KENNEDY SPACE CENTER, FLA. -- On Pad 17B, Cape Canaveral Air Station, a solid rocket booster hangs in place between two other rocket boosters waiting to be mated with the Delta II rocket carrying the Mars Polar Lander. The rocket will be used to launch the Mars Polar Lander on Jan. 3, 1999. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. It is the second spacecraft to be launched in a pair of Mars '98 missions. The first is the Mars Climate Orbiter, to be launched aboard a Delta II rocket from Launch Complex 17A in December 1998

KSC-98pc1826

NASA Image and Video Library

1998-12-02

KENNEDY SPACE CENTER, FLA. -- On Pad 17B, Cape Canaveral Air Station, the gantry holding the solid rocket boosters is moved into place next to the Delta II rocket carrying the Mars Polar Lander. The rocket will be used to launch the Mars Polar Lander on Jan. 3, 1999. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. It is the second spacecraft to be launched in a pair of Mars '98 missions. The first is the Mars Climate Orbiter, to be launched aboard a Delta II rocket from Launch Complex 17A in December 1998

KSC-98pc1830

NASA Image and Video Library

1998-12-02

KENNEDY SPACE CENTER, FLA. -- Inside the gantry on Pad 17B, Cape Canaveral Air Station, the fairing for the upper stages of the Delta II rocket carrying the Mars Polar Lander waits to be lowered into the white room. The rocket will be used to launch the Mars Polar Lander on Jan. 3, 1999. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. It is the second spacecraft to be launched in a pair of Mars '98 missions. The first is the Mars Climate Orbiter, to be launched aboard a Delta II rocket from Launch Complex 17A in December 1998

KSC-98pc1828

NASA Image and Video Library

1998-12-02

KENNEDY SPACE CENTER, FLA. -- The fairing for the upper stages of the Delta II rocket carrying the Mars Polar Lander is lifted to a vertical position on Pad 17B, Cape Canaveral Air Station. The rocket will be used to launch the Mars Polar Lander on Jan. 3, 1999. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. It is the second spacecraft to be launched in a pair of Mars '98 missions. The first is the Mars Climate Orbiter, to be launched aboard a Delta II rocket from Launch Complex 17A in December 1998

KSC-98pc1823

NASA Image and Video Library

1998-12-02

KENNEDY SPACE CENTER, FLA. -- On Pad 17B, Cape Canaveral Air Station, a solid rocket booster is raised to a vertical position for mating with the Delta II rocket carrying the Mars Polar Lander. The rocket will be used to launch the Mars Polar Lander on Jan. 3, 1999. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. It is the second spacecraft to be launched in a pair of Mars '98 missions. The first is the Mars Climate Orbiter, to be launched aboard a Delta II rocket from Launch Complex 17A in December 1998

KSC-98pc1625

NASA Image and Video Library

1998-11-10

KENNEDY SPACE CENTER, FLA. -- In the Spacecraft Assembly and Encapsulation Facility -2 (SAEF-2), the Mars Polar Lander is prepared to receive a number of microprobes being added to the spacecraft. Scheduled to be launched on Jan. 3, 1999, the solar-powered spacecraft is designed to touch down on the Martian surface near the northern-most boundary of the south pole in order to study the water cycle there. The lander also will help scientists learn more about climate change and current resources on Mars, studying such things as frost, dust, water vapor and condensates in the Martian atmosphere. The Mars microprobes will complement the climate-related scientific focus of the lander by demonstrating an advanced, rugged microlaser system for detecting subsurface water. Such data on polar subsurface water, in the form of ice, should help put limits on scientific projections for the global abundance of water on Mars

Electromagnetic ion cyclotron waves observed near the oxygen cyclotron frequency by ISEE 1 and 2

NASA Technical Reports Server (NTRS)

Fraser, B. J.; Samson, J. C.; Hu, Y. D.; Mcpherron, R. L.; Russell, C. T.

1992-01-01

The first results of observations of ion cyclotron waves by the elliptically orbiting ISEE 1 and 2 pair of spacecraft are reported. The most intense waves (8 nT) were observed in the outer plasmasphere where convection drift velocities were largest and the Alfven velocity was a minimum. Wave polarization is predominantly left-handed with propagation almost parallel to the ambient magnetic field, and the spectral slot and polarization reversal predicted by cold plasma propagation theory are identified in the wave data. Computations of the experimental wave spectra during the passage through the plasmapause show that the spectral slots relate to the local plasma parameters, possibly suggesting an ion cyclotron wave growth source near the spacecraft. A regular wave packet structure seen over the first 30 min of the event is attributed to the modulation of this energy source by the Pc 5 waves seen at the same time.

Electromagnetic ion cyclotron waves in the plasma depletion layer

NASA Technical Reports Server (NTRS)

Denton, Richard E.; Hudson, Mary K.; Fuselier, Stephen A.; Anderson, Brian J.

1993-01-01

Results of a study of the theoretical properties of electromagnetic ion cyclotron (EMIC) waves which occur in the plasma depletion layer are presented. The analysis assumes a homogeneous plasma with the characteristics which were measured by the AMPTE/CCE satellite at 1450-1501 UT on October 5, 1984. Waves were observed in the Pc 1 frequency range below the hydrogen gyrofrequency, and these waves are identified as EMIC waves. The higher-frequency instability is driven by the temperature anisotropy of the H(+) ions, while the lower-frequency instability is driven by the temperature anisotropy of the He(2+) ions. It is argued that the higher-frequency waves will have k roughly parallel to B(0) and will be left-hand polarized, while the lower frequency wave band will have k oblique to B(0) and will be linearly polarized, in agreement with observations.

Personal Computer Based Controller For Switched Reluctance Motor Drives

NASA Astrophysics Data System (ADS)

Mang, X.; Krishnan, R.; Adkar, S.; Chandramouli, G.

1987-10-01

Th9, switched reluctance motor (SRM) has recently gained considerable attention in the variable speed drive market. Two important factors that have contributed to this are, the simplicity of construction and the possibility of developing low cost con-trollers with minimum number of switching devices in the drive circuits. This is mainly due to the state-of-art of the present digital circuits technology and the low cost of switching devices. The control of this motor drive is under research. Optimized performance of the SRM motor drive is very dependent on the integration of the controller, converter and the motor. This research on system integration involves considerable changes in the control algorithms and their implementation. A Personal computer (PC) based controller is very appropriate for this purpose. Accordingly, the present paper is concerned with the design of a PC based controller for a SRM. The PC allows for real-time microprocessor control with the possibility of on-line system parameter modifications. Software reconfiguration of this controller is easier than a hardware based controller. User friendliness is a natural consequence of such a system. Considering the low cost of PCs, this controller will offer an excellent cost-effective means of studying the control strategies for the SRM drive intop greater detail than in the past.

A conserved SREBP-1/phosphatidylcholine feedback circuit regulates lipogenesis in metazoans.

PubMed

Walker, Amy K; Jacobs, René L; Watts, Jennifer L; Rottiers, Veerle; Jiang, Karen; Finnegan, Deirdre M; Shioda, Toshi; Hansen, Malene; Yang, Fajun; Niebergall, Lorissa J; Vance, Dennis E; Tzoneva, Monika; Hart, Anne C; Näär, Anders M

2011-11-11

Sterol regulatory element-binding proteins (SREBPs) activate genes involved in the synthesis and trafficking of cholesterol and other lipids and are critical for maintaining lipid homeostasis. Aberrant SREBP activity, however, can contribute to obesity, fatty liver disease, and insulin resistance, hallmarks of metabolic syndrome. Our studies identify a conserved regulatory circuit in which SREBP-1 controls genes in the one-carbon cycle, which produces the methyl donor S-adenosylmethionine (SAMe). Methylation is critical for the synthesis of phosphatidylcholine (PC), a major membrane component, and we find that blocking SAMe or PC synthesis in C. elegans, mouse liver, and human cells causes elevated SREBP-1-dependent transcription and lipid droplet accumulation. Distinct from negative regulation of SREBP-2 by cholesterol, our data suggest a feedback mechanism whereby maturation of nuclear, transcriptionally active SREBP-1 is controlled by levels of PC. Thus, nutritional or genetic conditions limiting SAMe or PC production may activate SREBP-1, contributing to human metabolic disorders. Copyright © 2011 Elsevier Inc. All rights reserved.

Dog rose (Rosa canina L.) as a functional ingredient in porcine frankfurters without added sodium ascorbate and sodium nitrite.

PubMed

Vossen, Els; Utrera, Mariana; De Smet, Stefaan; Morcuende, David; Estévez, Mario

2012-12-01

The effect of dog rose (Rosa canina L.; RC), rich in polyphenols and ascorbic acid, on lipid and protein oxidation, colour stability and texture of frankfurters was investigated. Four treatments were prepared: with 5 or 30 g/kg RC extract and without sodium ascorbate and sodium nitrite (5RC and 30RC, respectively), a positive control (with sodium ascorbate and sodium nitrite; PC) and a negative control (without sodium ascorbate, sodium nitrite or RC extract; NC). Hexanal values were much higher throughout storage in NC compared to RC and PC frankfurters (P<0.001). The RC extracts protected against protein oxidation, but not as efficiently as PC (P<0.05). In the RC treated frankfurters, lower a* values were measured compared to PC due to the lack of sodium nitrite. In conclusion, dog rose can act as a natural antioxidant in frankfurters, but not as full replacer for sodium nitrite. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of Soundscapes on Perceived Crowding and Encounter Norms

NASA Astrophysics Data System (ADS)

Kim, Sang-Oh; Shelby, Bo

2011-07-01

Soundscapes in recreation settings are becoming an important issue, but there are few studies of the effects of sounds on recreation experiences, especially crowding perceptions and encounter norms. This study compared effects of six types of sounds (an airplane, a truck engine, children playing, birds, water, and a control) on perceived crowding (PC) and encounter norms for hikers. Data were collected from 47 college students through lab experiments using simulated images, with moving hikers inserted in the original photo taken in the Jungmeori area of Mudeungsan Provincial Park in Korea. Overall, the motor-made sounds of the airplane and truck engine increased PC and decreased acceptability ratings, and the natural sounds of birds and water decreased PC and increased acceptability ratings. Ratings of the sound of children playing were similar to those in the control (i.e., no sound). In addition, as numbers of hikers increased, the overall effects of sounds decreased, and there were few significant differences in PC or acceptability ratings at the highest encounter levels. Theoretical and methodological implications are discussed.

Effects of soundscapes on perceived crowding and encounter norms.

PubMed

Kim, Sang-Oh; Shelby, Bo

2011-07-01

Soundscapes in recreation settings are becoming an important issue, but there are few studies of the effects of sounds on recreation experiences, especially crowding perceptions and encounter norms. This study compared effects of six types of sounds (an airplane, a truck engine, children playing, birds, water, and a control) on perceived crowding (PC) and encounter norms for hikers. Data were collected from 47 college students through lab experiments using simulated images, with moving hikers inserted in the original photo taken in the Jungmeori area of Mudeungsan Provincial Park in Korea. Overall, the motor-made sounds of the airplane and truck engine increased PC and decreased acceptability ratings, and the natural sounds of birds and water decreased PC and increased acceptability ratings. Ratings of the sound of children playing were similar to those in the control (i.e., no sound). In addition, as numbers of hikers increased, the overall effects of sounds decreased, and there were few significant differences in PC or acceptability ratings at the highest encounter levels. Theoretical and methodological implications are discussed.

The Effects of Organic Solvents on the Physicochemical Properties of Human Serum Albumin Nanoparticles.

PubMed

Mohammad-Beigi, Hossein; Shojaosadati, Seyed Abbas; Morshedi, Dina; Mirzazadeh, Negar; Arpanaei, Ayyoob

2016-03-01

Recently, applications of albumin nanoparticles as drug delivery carriers have increased. Most toxicology studies have shown that surface chemistry and size of nanoparticles play an important role in biocompatibility and toxicity. The effect of desolvating agents with different chemical properties on the size of synthesized HSA NPs was investigated. Acetone, ethanol, methanol, and acetonitrile were used to synthesize HSA NPs with controllable size by desolvation method. Scanning electron microscopy (SEM), dynamic light scattering (DLS), and circular dichroism (CD) were employed to characterize produced particles. Finally, the toxicity of HSA NPs synthesized under different conditions was evaluated on PC-12 cells. The sizes of synthesized particles differed according to the different solvents used. The sizes were 275.3 nm, 155.3 nm, 100.11 nm, and 66.2 nm for acetonitrile, ethanol, acetone, and methanol, respectively. CD showed that larger NPs had more changes in the secondary structures. Finally, the toxicity monitored on the cultured PC-12 cells showed no significant toxic effect through treating with these NPs at different concentrations (0-500 μg.mL -1 ). The size of HSA NPs has a strong dependency on the desolvating agent. The mechanism in which the desolvating agent affects the size of HSA NPs is complex. Various factors such as dielectric constant, polarity, functional groups, and hydrogen bonding of the solvents have the potential to affect the size and structure of HSA NPs. CD analysis suggested that the solvent denaturing capability had a critical effect on the HSA particle size. The stronger denaturing capability of the solvent resulted in the larger HSA particle size.

JAK/STAT autocontrol of ligand-producing cell number through apoptosis.

PubMed

Borensztejn, Antoine; Boissoneau, Elisabeth; Fernandez, Guillaume; Agnès, François; Pret, Anne-Marie

2013-01-01

During development, specific cells are eliminated by apoptosis to ensure that the correct number of cells is integrated in a given tissue or structure. How the apoptosis machinery is activated selectively in vivo in the context of a developing tissue is still poorly understood. In the Drosophila ovary, specialised follicle cells [polar cells (PCs)] are produced in excess during early oogenesis and reduced by apoptosis to exactly two cells per follicle extremity. PCs act as an organising centre during follicle maturation as they are the only source of the JAK/STAT pathway ligand Unpaired (Upd), the morphogen activity of which instructs distinct follicle cell fates. Here we show that reduction of Upd levels leads to prolonged survival of supernumerary PCs, downregulation of the pro-apoptotic factor Hid, upregulation of the anti-apoptotic factor Diap1 and inhibition of caspase activity. Upd-mediated activation of the JAK/STAT pathway occurs in PCs themselves, as well as in adjacent terminal follicle and interfollicular stalk cells, and inhibition of JAK/STAT signalling in any one of these cell populations protects PCs from apoptosis. Thus, a Stat-dependent unidentified relay signal is necessary for inducing supernumerary PC death. Finally, blocking apoptosis of PCs leads to specification of excess adjacent border cells via excessive Upd signalling. Our results therefore show that Upd and JAK/STAT signalling induce apoptosis of supernumerary PCs to control the size of the PC organising centre and thereby produce appropriate levels of Upd. This is the first example linking this highly conserved signalling pathway with developmental apoptosis in Drosophila.

Data communication between Panasonic PLC and PC using SerialPort control in C#.NET environment

NASA Astrophysics Data System (ADS)

Gao, Ting; Gan, Xiaochuan; Ma, Liqun

2015-02-01

With the gradual promotion of Microsoft.NET platform, C# as an object-oriented programming language based on the platform has been widely used. Therefore, more attention is concentrated on how to achieve the communication between Panasonic PLC and PC efficiently and fast in C#.NET environment. In this paper, a method of using SerialPort control which could be used for achieving communication between PLC and PC is introduced. Meanwhile, the reason of abnormal thread when displayed the receiving data in form is analyzed and the programming method to solve the problem of thread safety is designed. Achieving the communication of Panasonic PLC and PC in C#.NET environment can give full play to the advantages of the .NET framework. It is practical, easy communication, high reliability and can combine with other measurement and calibration procedures effectively and conveniently. Configuration software is expensive and can only communicate with PLC separately, but these shortcomings can be solved in C#.NET environment. A well-designed user interface realized real-time monitoring of PLC parameters and achieved management and control integration. The experiment show that this method of data transfer is accurate and the program' running is stable.

A phase II study in advanced cancer patients to evaluate the early transition to palliative care (the PREPArE trial): protocol study for a randomized controlled trial.

PubMed

do Carmo, Thamires Monteiro; Paiva, Bianca Sakamoto Ribeiro; de Siqueira, Milena Ruas; da Rosa, Luciana de Toledo Bernardes; de Oliveira, Cleyton Zanardo; Nascimento, Maria Salete de Angelis; Paiva, Carlos Eduardo

2015-04-12

Previous studies have demonstrated the benefit of early integration of palliative care (PC) in oncology. However, patients continue to receive late referrals to PC even in comprehensive cancer centers. Patients and health professionals may perceive PC as 'a place to die,' and this stigma is a barrier to timely referrals and to patient acceptance of treatment. The primary objective is to evaluate the feasibility of psychosocial intervention and PC in patients with advanced cancer. The patients will be submitted to a series of brief psychosocial interventions that are based on cognitive behavioral therapy, and patient acceptance and satisfaction will be assessed. In addition, the impact of these interventions on depressive symptoms will be evaluated. A randomized, open-label, phase II trial with two intervention arms and a control group will be conducted. Patients who are started on palliative chemotherapy and who meet the inclusion criteria will be enrolled. The study participants will be recruited from the outpatient oncology clinics at Barretos Cancer Hospital and will be randomized into one of the following three treatment arms: Arm A, which will include five weekly psychosocial interventions based on CBT in combination with early PC; Arm B, which will include early PC only; and Arm C, which will include standard oncologic care. The Hospital Anxiety and Depression Scale (HADS), the Patient Health Questionnaire (PHQ-9), the Edmonton Symptom Assessment System (ESAS-br), the Family Satisfaction with End-of-Life Care (FAMCARE)-Patient scale, and the Disease Understanding Protocol will be used for data collection. The patients will answer these questionnaires at baseline and 45, 90, 120 and 180 days after randomization. Despite evidence of the positive impact of early PC, it is often provided to patients only at later stages. The inadequate awareness and stigmatization of PC as a place to die are barriers that complicate the early referral. Patients with advanced cancer may benefit from a psychosocial and educational strategy that adequately prepares them for initial PC appointments after an early referral to PC. We anticipate that benefits of psychological intervention shall be synergistic to secondary emotional benefits from the early integration of PC. This trial was registered on 6 May 2014 with ClinicalTrials.gov (identifier: NCT02133274).

Prostate-Specific Antigen (PSA)–Based Population Screening for Prostate Cancer: An Evidence-Based Analysis

PubMed Central

Pron, G

2015-01-01

Background Prostate cancer (PC) is the most commonly diagnosed non-cutaneous cancer in men and their second or third leading cause of cancer death. Prostate-specific antigen (PSA) testing for PC has been in common practice for more than 20 years. Objectives A systematic review of the scientific literature was conducted to determine the effectiveness of PSA-based population screening programs for PC to inform policy decisions in a publicly funded health care system. Data Sources A systematic review of bibliographic databases was performed for systematic reviews or randomized controlled trials (RCT) of PSA-based population screening programs for PC. Review Methods A broad search strategy was employed to identify studies reporting on key outcomes of PC mortality and all-cause mortality. Results The search identified 5 systematic reviews and 6 RCTs. None of the systematic reviews found a statistically significant reduction in relative risk (RR) of PC mortality or overall mortality with PSA-based screening. PC mortality reductions were found to vary by country, by screening program, and by age of men at study entry. The European Randomized Study of Screening for Prostate Cancer found a statistically significant reduction in RR in PC mortality at 11-year follow-up (0.79; 95% CI, 0.67–0.92), although the absolute risk reduction was small (1.0/10,000 person-years). However, the primary treatment for PCs differed significantly between countries and between trial arms. The American Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) found a statistically non-significant increase in RR for PC mortality with 13-year follow-up (1.09; 95% CI, 0.87–1.36). The degree of opportunistic screening in the control arm of the PLCO trial, however, was high. None of the RCTs found a reduction in all-cause mortality and all found a statistically significant increase in the detection of mainly low-risk, organ-confined PCs in the screening arm. Conclusions There was no evidence of a PC mortality reduction in the American PLCO trial, which investigated a screening program in a setting where opportunistic screening was already common practice. Given that opportunistic PSA screening practices in Canada are similar, it is unlikely that the introduction of a formal PSA screening program would reduce PC mortality. PMID:26366236

Prostate-Specific Antigen (PSA)-Based Population Screening for Prostate Cancer: An Evidence-Based Analysis.

PubMed

Pron, G

2015-01-01

Prostate cancer (PC) is the most commonly diagnosed non-cutaneous cancer in men and their second or third leading cause of cancer death. Prostate-specific antigen (PSA) testing for PC has been in common practice for more than 20 years. A systematic review of the scientific literature was conducted to determine the effectiveness of PSA-based population screening programs for PC to inform policy decisions in a publicly funded health care system. A systematic review of bibliographic databases was performed for systematic reviews or randomized controlled trials (RCT) of PSA-based population screening programs for PC. A broad search strategy was employed to identify studies reporting on key outcomes of PC mortality and all-cause mortality. The search identified 5 systematic reviews and 6 RCTs. None of the systematic reviews found a statistically significant reduction in relative risk (RR) of PC mortality or overall mortality with PSA-based screening. PC mortality reductions were found to vary by country, by screening program, and by age of men at study entry. The European Randomized Study of Screening for Prostate Cancer found a statistically significant reduction in RR in PC mortality at 11-year follow-up (0.79; 95% CI, 0.67-0.92), although the absolute risk reduction was small (1.0/10,000 person-years). However, the primary treatment for PCs differed significantly between countries and between trial arms. The American Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) found a statistically non-significant increase in RR for PC mortality with 13-year follow-up (1.09; 95% CI, 0.87-1.36). The degree of opportunistic screening in the control arm of the PLCO trial, however, was high. None of the RCTs found a reduction in all-cause mortality and all found a statistically significant increase in the detection of mainly low-risk, organ-confined PCs in the screening arm. There was no evidence of a PC mortality reduction in the American PLCO trial, which investigated a screening program in a setting where opportunistic screening was already common practice. Given that opportunistic PSA screening practices in Canada are similar, it is unlikely that the introduction of a formal PSA screening program would reduce PC mortality.

Fuzzy control of small servo motors

NASA Technical Reports Server (NTRS)

Maor, Ron; Jani, Yashvant

1993-01-01

To explore the benefits of fuzzy logic and understand the differences between the classical control methods and fuzzy control methods, the Togai InfraLogic applications engineering staff developed and implemented a motor control system for small servo motors. The motor assembly for testing the fuzzy and conventional controllers consist of servo motor RA13M and an encoder with a range of 4096 counts. An interface card was designed and fabricated to interface the motor assembly and encoder to an IBM PC. The fuzzy logic based motor controller was developed using the TILShell and Fuzzy C Development System on an IBM PC. A Proportional-Derivative (PD) type conventional controller was also developed and implemented in the IBM PC to compare the performance with the fuzzy controller. Test cases were defined to include step inputs of 90 and 180 degrees rotation, sine and square wave profiles in 5 to 20 hertz frequency range, as well as ramp inputs. In this paper we describe our approach to develop a fuzzy as well as PH controller, provide details of hardware set-up and test cases, and discuss the performance results. In comparison, the fuzzy logic based controller handles the non-linearities of the motor assembly very well and provides excellent control over a broad range of parameters. Fuzzy technology, as indicated by our results, possesses inherent adaptive features.

Application of Field System-FS9 and a PC to Antenna Control Unit interface in Radio Astronomy in Peru

NASA Astrophysics Data System (ADS)

Vidal, E. V. S.; Ishitsuka, J. I. I.; Koyama, K. Y.

2006-08-01

We are in the process to transform a 32m antenna in Peru, used for telecommunications, into a Radio Telescope to perform Radio Astronomy in Peru. The 32m antenna of Peru constructed by NEC was used for telecommunications with communications satellites at 6 GHz for transmission, and 4 GHz for reception. In collaboration of National Institute of Information and Communications Technology (NICT) Japan, and National Observatory of Japan we developed an Antenna Control System for the 32m antenna in Peru. It is based on the Field System FS9, software released by NASA for VLBI station, and an interface to link PC within FS9 software (PC-FS9) and Antenna Control Unit (ACU) of the 32 meters antenna. The PC-FS9 controls the antenna, commands are translated by interface into control signals compatibles with the ACU using: an I/O digital card with two 20bits ports to read azimuth and elevation angles, one 16bits port for reading status of ACU, one 24bits port to send pulses to start or stop operations of antenna, two channels are analogic outputs to drive the azimuth and elevation motors of the antenna, a LCD display to show the status of interface and error messages, and one serial port for communications with PC-FS9,. The first experiment of the control system was made with 11m parabolic antenna of Kashima Space Research Center (NICT), where we tested the right working of the routines implemented for de FS9 software, and simulations was made with looped data between output and input of the interface, both test were done successfully. With this scientific instrument we will be able to contribute with researching of astrophysics. We expect to into a near future to work at 6.7GHz to study Methanol masers, and higher frequencies with some improvements of the surface of the dish.

PC4/Tis7/IFRD1 Stimulates Skeletal Muscle Regeneration and Is Involved in Myoblast Differentiation as a Regulator of MyoD and NF-κB*

PubMed Central

Micheli, Laura; Leonardi, Luca; Conti, Filippo; Maresca, Giovanna; Colazingari, Sandra; Mattei, Elisabetta; Lira, Sergio A.; Farioli-Vecchioli, Stefano; Caruso, Maurizia; Tirone, Felice

2011-01-01

In skeletal muscle cells, the PC4 (Tis7/Ifrd1) protein is known to function as a coactivator of MyoD by promoting the transcriptional activity of myocyte enhancer factor 2C (MEF2C). In this study, we show that up-regulation of PC4 in vivo in adult muscle significantly potentiates injury-induced regeneration by enhancing myogenesis. Conversely, we observe that PC4 silencing in myoblasts causes delayed exit from the cell cycle, accompanied by delayed differentiation, and we show that such an effect is MyoD-dependent. We provide evidence revealing a novel mechanism underlying the promyogenic actions of PC4, by which PC4 functions as a negative regulator of NF-κB, known to inhibit MyoD expression post-transcriptionally. In fact, up-regulation of PC4 in primary myoblasts induces the deacetylation, and hence the inactivation and nuclear export of NF-κB p65, in concomitance with induction of MyoD expression. On the contrary, PC4 silencing in myoblasts induces the acetylation and nuclear import of p65, in parallel with a decrease of MyoD levels. We also observe that PC4 potentiates the inhibition of NF-κB transcriptional activity mediated by histone deacetylases and that PC4 is able to form trimolecular complexes with p65 and HDAC3. This suggests that PC4 stimulates deacetylation of p65 by favoring the recruitment of HDAC3 to p65. As a whole, these results indicate that PC4 plays a role in muscle differentiation by controlling the MyoD pathway through multiple mechanisms, and as such, it positively regulates regenerative myogenesis. PMID:21127072

Dietary phosphatidylcholine impacts on growth performance and lipid metabolism in adult Genetically Improved Farmed Tilapia (GIFT) strain of Nile tilapia Oreochromis niloticus.

PubMed

Tian, Juan; Wen, Hua; Lu, Xing; Liu, Wei; Wu, Fan; Yang, Chang-Geng; Jiang, Ming; Yu, Li-Juan

2018-01-01

This study aimed to determine the effects of supplementing the diet of adult Nile tilapia Oreochromis niloticus with phosphatidylcholine (PC) on growth performance, body composition, fatty acid composition and gene expression. Genetically Improved Farmed Tilapia fish with an initial body weight of 83·1 (sd 2·9) g were divided into six groups. Each group was hand-fed a semi-purified diet containing 1·7 (control diet), 4·0, 6·5, 11·5, 21·3 or 41·0 g PC/kg diet for 68 d. Supplemental PC improved the feed efficiency rate, which was highest in the 11·5 g PC/kg diet. Weight gain and specific growth rate were unaffected. Dietary PC increased PC content in the liver and decreased crude fat content in the liver, viscera and body. SFA and MUFA increased and PUFA decreased in muscle with increasing dietary PC. Cytoplasmic phospholipase A 2 and secreted phospholipase A 2 mRNA expression were up-regulated in the brain and heart in PC-supplemented fish. PC reduced fatty acid synthase mRNA expression in the liver and visceral tissue but increased expression in muscle. Hormone-sensitive lipase and lipoprotein lipase expression increased in the liver with increasing dietary PC. Growth hormone mRNA expression was reduced in the brain and insulin-like growth factor-1 mRNA expression in liver reduced with PC above 6·5 g/kg. Our results demonstrate that dietary supplementation with PC improves feed efficiency and reduces liver fat in adult Nile tilapia, without increasing weight gain, representing a novel dietary approach to reduce feed requirements and improve the health of Nile tilapia.

Targeted Elimination of PCDH-PC Expressing Prostate Cancer Cells for Control of Hormone-Resistant Prostate Cancer

DTIC Science & Technology

2008-11-01

or antisense oligonucleotides ( ASOs ) might be useful in preventing the development of castration- recurrent prostate cancer in prostate cancer...patients. To this end, we have created functional shRNA vectors and ASOs capable of suppressing PCDH-PC expression and we have also created a monoclonal...electrophoresed on an SDS-PAGE gel and blotted onto a filter. The filter was probed with an anti-myc antibody. The levels of myc-tagged PCDH-PC protein

Targeted Elimination of PCDH-PC Expressing Prostate Cancer Cells for Control of Hormone-Resistant Prostate Cancer

DTIC Science & Technology

2007-11-01

SDS-PAGE gel . The Western blot made from this gel was probed with antibody that recognizes the myc-tag. When compared to the extracts from the...SDS-PAGE gel and blotted onto a filter. The filter was probed with an anti-myc antibody. The levels of myc-tagged PCDH-PC protein in cells co...Specific Aim 2. Design and test antisense oligonucleotides ( ASOs ) that suppress PCDH-PC expression in prostate cancer cells. Work Done: We used

Targeted Elimination of PCDH-PC Expressing Prostate Cancer Cells for Control of Hormone-Resistant Prostate Cancer

DTIC Science & Technology

2009-11-01

expression knockout by shRNAs or antisense oligonucleotides ( ASOs ) might be useful in preventing the development of castration-recurrent prostate...cancer in prostate cancer patients. To this end, we have created functional shRNA vectors and ASOs capable of suppressing PCDH-PC expression and we have...containing PCDH-PC cDNA. Cell extracts were prepared 48 hrs after co-transfection and were electrophoresed on an SDS-PAGE gel and blotted onto a

Adopting Industry Standards for Control Systems Within Advanced Life Support

NASA Technical Reports Server (NTRS)

Young, James Scott; Boulanger, Richard

2002-01-01

This paper gives a description of OPC (Object Linking and Embedding for Process Control) standards for process control and outlines the experiences at JSC with using these standards to interface with I/O hardware from three independent vendors. The I/O hardware was integrated with a commercially available SCADA/HMI software package to make up the control and monitoring system for the Environmental Systems Test Stand (ESTS). OPC standards were utilized for communicating with I/O hardware and the software was used for implementing monitoring, PC-based distributed control, and redundant data storage over an Ethernet physical layer using an embedded din-rail mounted PC.

The ISOLDE control system

NASA Astrophysics Data System (ADS)

Deloose, I.; Pace, A.

1994-12-01

The two CERN isotope separators named ISOLDE have been running on the new Personal Computer (PC) based control system since April 1992. The new architecture that makes heavy use of the commercial software and hardware of the PC market has been implemented on the 1700 geographically distributed control channels of the two separators and their experimental area. Eleven MSDOS Intel-based PCs with approximately 80 acquisition and control boards are used to access the equipment and are controlled from three PCs running Microsoft Windows used as consoles through a Novell Local Area Network. This paper describes the interesting solutions found and discusses the reduced programming workload and costs that have been obtained.

CD59 Underlines the Antiatherosclerotic Effects of C-Phycocyanin on Mice

PubMed Central

Chu, Xian-Ming; Xu, Ying-Jie; Yang, Fan; Lv, Cong-Yi; Nie, Shu-min

2013-01-01

The effects of C-phycocyanin (C-PC) on atherosclerosis and the regulatory effects of CD59 gene on anti-atherosclerotic roles of C-PC were investigated. Apolipoprotein E knockout (ApoE(−/−)) mice were randomly divided into four groups: control group, C-PC treatment group, CD59 transfection group and C-PC+CD59 synergy group. The mice were fed with high-fat-diet and treated with drug intervention at the same time. Results showed the atherosclerotic mouse model was successfully established. CD59 was over-expressed in blood and tissue cells. Single CD59 or C-PC could reduce blood lipid levels and promote the expression of anti-apoptotic Bcl-2 but inhibit pro-apoptotic Fas proteins in endothelial cells. The expression levels of cell cycle protein D1 (Cyclin D1) and mRNA levels of cyclin dependent protein kinase 4 (CDK4) in smooth muscle cells were restrained by CD59 and C-PC. CD59 or C-PC alone could inhibit the formation of atherosclerotic plaque by suppressing MMP-2 protein expression. In addition, C-PC could promote CD59 expression. So both CD59 and C-PC could inhibit the progress of atherosclerosis, and the anti-atherosclerotic effects of C-PC might be fulfilled by promoting CD59 expression, preventing smooth muscle cell proliferation and the apoptosis of endothelial cells, reducing blood fat levels, and at last inhibiting the development of atherosclerosis. PMID:24319687

Control of Mechanical Properties of Thermoplastic Polyurethane Elastomers by Restriction of Crystallization of Soft Segment

PubMed Central

Kojio, Ken; Furukawa, Mutsuhisa; Nonaka, Yoshiteru; Nakamura, Sadaharu

2010-01-01

Mechanical properties of thermoplastic polyurethane elastomers based on either polyether or polycarbonate (PC)-glycols, 4,4’-dipheylmethane diisocyanate (1,1’-methylenebis(4-isocyanatobenzene)), 1,4-butanediol, were controlled by restriction of crystallization of polymer glycols. For the polyether glycol based-polyurethane elastomers (PUEs), poly(oxytetramethylene) glycol (PTMG), and PTMG incorporating dimethyl groups (PTG-X) and methyl side groups (PTG-L) were employed as a polymer glycol. For the PC-glycol, the randomly copolymerized PC-glycols with hexamethylene (C6) and tetramethylene (C4) units between carbonate groups with various composition ratios (C4/C6 = 0/100, 50/50, 70/30 and 90/10) were employed. The degree of microphase separation and mechanical properties of both the PUEs were investigated using differential scanning calorimetry, dynamic viscoelastic property measurements and tensile testing. Mechanical properties could be controlled by changing the molar ratio of two different monomer components. PMID:28883371

Coherent active polarization control without loss

NASA Astrophysics Data System (ADS)

Ye, Yuqian; Hay, Darrick; Shi, Zhimin

2017-11-01

We propose a lossless active polarization control mechanism utilizing an anisotropic dielectric medium with two coherent inputs. Using scattering matrix analysis, we derive analytically the required optical properties of the anisotropic medium that can behave as a switchable polarizing beam splitter. We also show that such a designed anisotropic medium can produce linearly polarized light at any azimuthal direction through coherent control of two inputs with a specific polarization state. Furthermore, we present a straightforward design-on-demand procedure of a subwavelength-thick metastructure that can possess the desired optical anisotropy at a flexible working wavelength. Our lossless coherent polarization control technique may lead to fast, broadband and integrated polarization control elements for applications in imaging, spectroscopy, and telecommunication.

Interaction of ozone exposure with airway hyperresponsiveness and inflammation induced by trimellitic anhydride in sensitized guinea pigs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Jian; Chung, K.Fan

1997-09-01

The effect of prior ozone (O{sub 3}) exposure on airway hyperresponsiveness and inflammation induced by trimellitic anhydride (TMA) has been investigated in TMA-sensitized guinea pigs. Airway responsiveness was measured as the concentration of acetylcholine needed to increase baseline lung resistance (RL) by 300% (PC300). Ozone (3 ppm, for 3 h) caused an increase in-log PC300 at 1 h after exposure, with return of -log PC300 to control levels at 8 h. Ozone also increased baseline RL at 8 h. TMA challenge increase -log PC300 in TMA-sensitized guinea pigs at 8 h after challenge from 3.85 {+-} 0.09 to 4.11 {+-}more » 0.09. Ozone exposure prior to TMA challenge prevented the induction of airway hyperresponsiveness with a mean -log PC300 of 3.51 {+-} 0.20, which was not different from that of control TMA-Sensitized group. Baseline RL was significantly higher in ozone-pretreated animals after TMA challenge when compared to those of either control or challenged with TMA alone. Ozone had no effect on TMA challenge-induced BAL eosinophilia and neutrophilia. We conclude that a single exposure to ozone inhibits the increase in airway responsiveness, but increases the bronchoconstrictor response induced by TMA in TMA-Sensitized guinea pigs; however, the inflammatory airway response to TMA is unchanged by preexposure to ozone. 29 refs., 2 figs., 1 tab.« less

The ULT trxG Fatcors play a role in Arabidopsis Fertilization

USDA-ARS?s Scientific Manuscript database

Trithorax group (trxG) and Polycomb group (PcG) proteins are epigenetic modifiers that play key roles in eukaryotic development by promoting active or repressive gene expression states, respectively. Although PcG proteins have well-defined roles in controlling developmental transitions, cell fate de...

Positron Interactions with Oriented Polymers and with Chiral Quartz Crystals

NASA Astrophysics Data System (ADS)

Wu, Fei

Positron annihilation in various materials has been applied to characterize microstructure for decades. In this work, PALS was used to study material nanostructure, with a focus on the size and density of free volume and hole relaxation properties in polycarbonate (PC) and polymethylmethacrylate (PMMA); fundamental studies of polarized positron interaction with chiral crystals were also studied. Free volume relaxation in PC and PMMA with different levels of simple shear orientation was studied by PALS. Effects of applied pressure on the free volume recovery were evaluated. Combining the bulk- and pressure-dependent PALS analyses, the removal of applied pressure led to free-volume relaxation in all samples studied. The alignment of the polymer chains and free-volume holes imposes molecular restrictions on the molecular mobility of both PC and PMMA in their glassy states. Results indicated that the relaxation of the free volume holes at temperatures below glass transition is mostly reversible. Longitudinally polarized positron particles were used to reveal asymmetric interactions in chiral quartz crystals. Experimental results showed a significant intensity difference in free positronium annihilation for left handed (LH) and right handed (RH) chiral quartz crystals. Doppler broadening energy spectra (DBES) of z-cut LH or RH quartz disks at different angles were also measured by an "S parameter" to probe the observed difference. It was found that obtained annihilation energy difference of DBES was in agreement with the result of positron annihilation in bulk chiral crystals. PALS was used to compare different orientations and confirm asymmetric interactions in natural versus synthetic quartz LH and RH crystals in z and non-z orientations. Significant lifetime and intensity differences in free positronium annihilation for LH and RH quartz crystals were observed. The trend was found to be same in the related crystallographic orientations of the LH or RH crystals; the direction of incident positrons, z or non-z, did not affect the observed differences in lifetime and intensity trends. The results confirmed the existence of differential interactions of positronium with the asymmetric lattice structures of LH and RH quartz crystals.

Characterization of interactions of eggPC lipid structures with different biomolecules.

PubMed

Corrales Chahar, F; Díaz, S B; Ben Altabef, A; Gervasi, C; Alvarez, P E

2018-01-01

In this paper we study the interactions of two biomolecules (ascorbic acid and Annonacin) with a bilayer lipid membrane. Egg yolk phosphatidylcholine (eggPC) liposomes (in crystalline liquid state) were prepared in solutions of ascorbic acid (AA) at different concentration levels. On the other hand, liposomes were doped with Annonacin (Ann), a mono-tetrahydrofuran acetogenin (ACG), which is an effective citotoxic substance. While AA pharmacologic effect and action mechanisms are widely known, those of Ann's are only very recently being studied. Both Fourier Transformed Infrared (FTIR) and Raman spectroscopic techniques were used to study the participation of the main functional groups of the lipid bilayer involved in the membrane-solution interaction. The obtained spectra were comparatively analyzed, studying the spectral bands corresponding to both the hydrophobic and the hydrophilic regions in the lipid bilayer. Electrochemical experiments namely; impedance spectroscopy (EIS) and cyclic voltamperometry (CV) were used as the main characterization techniques to analyse stability and structural changes of a model system of supported EggPC bilayer in connection with its interactions with AA and Ann. At high molar ratios of AA, there is dehydration in both populations of the carbonyl group of the polar head of the lipid. On the other hand, Ann promotes the formation of hydrogen bonds with the carbonyl groups. No interaction between AA and phosphate groups is observed at low and intermediate molar ratios. Ann is expected to be able to induce the dehydration of the phosphate groups without the subsequent formation of H bonds with them. According to the electrochemical analysis, the interaction of AA with the supported lipid membrane does not alter its dielectric properties. This fact can be related to the conservation of structured water of the phosphate groups in the polar heads of the lipid. On the other hand, the incorporation of Ann into the lipid membrane generates an increase in the number of defects while changes the dielectric constant. This, in turn, can be associated with the induced dehydration of the phosphate groups. Copyright © 2017 Elsevier B.V. All rights reserved.

Cobalt Phthalocyanine Modified Electrodes Utilised in Electroanalysis: Nano-Structured Modified Electrodes vs. Bulk Modified Screen-Printed Electrodes

PubMed Central

Foster, Christopher W.; Pillay, Jeseelan; Metters, Jonathan P.; Banks, Craig E.

2014-01-01

Cobalt phthalocyanine (CoPC) compounds have been reported to provide electrocatalytic performances towards a substantial number of analytes. In these configurations, electrodes are typically constructed via drop casting the CoPC onto a supporting electrode substrate, while in other cases the CoPC complex is incorporated within the ink of a screen-printed sensor, providing a one-shot economical and disposable electrode configuration. In this paper we critically compare CoPC modified electrodes prepared by drop casting CoPC nanoparticles (nano-CoPC) onto a range of carbon based electrode substrates with that of CoPC bulk modified screen-printed electrodes in the sensing of the model analytes l-ascorbic acid, oxygen and hydrazine. It is found that no “electrocatalysis” is observed towards l-ascorbic acid using either of these CoPC modified electrode configurations and that the bare underlying carbon electrode is the origin of the obtained voltammetric signal, which gives rise to useful electroanalytical signatures, providing new insights into literature reports where “electrocatalysis” has been reported with no clear control experiments undertaken. On the other hand true electrocatalysis is observed towards hydrazine, where no such voltammetric features are witnessed on the bare underlying electrode substrate. PMID:25414969

Magnetic fields in the torus of AGN and Mid-IR polarimetry of Cygnus A

NASA Astrophysics Data System (ADS)

Lopez-Rodriguez, E.; Packham, C.; Young, S.; Elitzur, M.; Levenson, N. A.; Mason, R. E.; Ramos Almeida, C.; Alonso-Herrero, A.; Jones, T. J.; Perlman, E.

2012-12-01

An optically and geometrically thick torus obscures the central engine of Active Galactic Nuclei (AGN) from some lines of sight. From a magnetohydrodynamical framework, the torus can be considered to be a particular region of clouds surrounding the central engine where the clouds are dusty and optically thick. In this framework, the magnetic field plays an important role in the creation, morphology and evolution of the torus. If the dust grains within the clouds are assumed to be aligned by paramagnetic alignment, then the ratio of the intrinsic polarisation and visual extinction, P(%)/Av, is a function of the magnetic field strength. To estimate the visual extinction through the torus and constrain the polarisation mechanisms in the nucleus of AGN, we developed a polarisation model to fit both the total and polarised flux in a 1.2" (˜ 263 pc) aperture of the type 2 AGN, IC5063. We consider the physical conditions and environment of the gas and dust for the torus of IC5063. Then, through paramagnetic alignment, we estimate a magnetic field strength in the range of 12 - 128 mG in the NIR emitting regions of the torus of IC5063. Alternatively, we estimate the magnetic field strength in the plane of the sky using the Chandrasekhar-Fermi method. The minimum magnetic field strength in the plane of the sky is estimated to be 13 and 41 mG depending of the conditions within the torus of IC5063. These techniques afford the chance to make a survey of AGN, to investigate the effects of magnetic field strength on the torus, accretion, and interaction to the host galaxy. We present Si2 [8.7 um] and Si5 [11.6 um] imaging polarimetry of Cygnus A using CanariCam on the 10.4-m Gran Telescopio de Canarias (GTC). Preliminary polarimetric results show a highly polarized nucleus with 11±3% and 12±3% in a 0.5" (˜500pc) aperture in Si2 and Si5, respectively. The PA of polarization remains constant, 32±8 deg, in both filters. In order to disentangle the origin of the polarized component in the nucleus of Cygnus A, further modeling using several polarizing mechanisms e.g. synchrotron, dichroic absorption/emission and/or scattering will be performed.

Influence of Tm+3 concentration on the non-linear optical effects of the BiB3O6 : Tm3+ glass nanoparticle-doped polymer

NASA Astrophysics Data System (ADS)

Majchrowski, A.; Ebothe, J.; Ozga, K.; Kityk, I. V.; Reshak, A. H.; Lukasiewicz, T.; Brik, M. G.

2010-01-01

It is shown that BiB3O6 : Tm3+ glass nanoparticles incorporated into polymethylmethacrylate (PMMA) and polycarbonate (PC) polymer matrices show good second-order susceptibilities under bicolour coherent laser treatment. It is found that only during incorporation into highly polarized PC matrices could one observe an enhancement of the second-order susceptibilities with increasing laser treated power densities. The main increase is observed for all samples at power densities equal to about 0.4 GW cm-2. After passing this value there is a saturation of the output susceptibilities and even an abrupt decrease. The most striking feature is the achievement of second-order susceptibilities equal to about 5 pm V-1 for samples containing 4% nanoparticle (NP) content in the PC matrix. A further increase in the NP concentration to 6% leads to a decrease in susceptibility to 15%. In the case of PMMA matrices these changes do not exceed the background. The same situation is present for the pure BIBO and low-doped Tm materials. The effect is maximal for a low concentration of Tm—about 0.75%. In the case of bulk glasses the intensity dependences of the second-harmonic generation unambiguously show that the achieved maximal values of second-order susceptibilities do not exceed 3 pm V-1 for 0.5% Tm concentration.

Oriented thin films of mixture of a low-bandgap polymer and a fullerene derivative prepared by friction-transfer method

NASA Astrophysics Data System (ADS)

Tanigaki, Nobutaka; Mizokuro, Toshiko; Miyadera, Tetsuhiko; Shibata, Yousei; Koganezawa, Tomoyuki

2018-02-01

We have been studying oriented thin films of polymers fabricated by the friction-transfer method, which allows the alignment of a variety of conjugated polymers into highly oriented films. In this study, we prepared oriented blend films of a mixture of a low-bandgap polymer, poly{4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b‧]dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophene-4,6-diyl} (PTB7), and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM), which is a promising combination for application in organic solar cells. We obtained oriented blend films of PTB7 and PC71BM by the friction-transfer method from a solid block. Polarized UV-visible spectra show that the PTB7 chains were aligned parallel to the friction direction in the blend films. Grazing-incidence X-ray diffraction (GIXD) studies with synchrotron radiation suggested that the preferred orientation of PTB7 crystallites was face-on in the blend films. The GIXD results also showed the high uniaxial orientation of PTB7 chains in blend films. Photovoltaic devices were fabricated using the friction-transferred blend films of the PTB7 and PC71BM. These bulk heterojunction devices showed better performance than planar heterojunction devices fabricated using pure friction-transferred PTB7 films.

Multivariate optimization of a synergistic blend of oleoresin sage (Salvia officinalis L.) and ascorbyl palmitate to stabilize sunflower oil.

PubMed

Upadhyay, Rohit; Mishra, Hari Niwas

2016-04-01

The simultaneous optimization of a synergistic blend of oleoresin sage (SAG) and ascorbyl palmitate (AP) in sunflower oil (SO) was performed using central composite and rotatable design coupled with principal component analysis (PCA) and response surface methodology (RSM). The physicochemical parameters viz., peroxide value, anisidine value, free fatty acids, induction period, total polar matter, antioxidant capacity and conjugated diene value were considered as response variables. PCA reduced the original set of correlated responses to few uncorrelated principal components (PC). The PC1 (eigen value, 5.78; data variance explained, 82.53 %) was selected for optimization using RSM. The quadratic model adequately described the data (R (2) = 0. 91, p < 0.05) and lack of fit was insignificant (p > 0.05). The contour plot of PC 1 score indicated the optimal synergistic combination of 1289.19 and 218.06 ppm for SAG and AP, respectively. This combination of SAG and AP resulted in shelf life of 320 days at 25 °C estimated using linear shelf life prediction model. In conclusion, the versatility of PCA-RSM approach has resulted in an easy interpretation in multiple response optimizations. This approach can be considered as a useful guide to develop new oil blends stabilized with food additives from natural sources.

High-Altitude Particle Acceleration and Radiation in Pulsar Slot Gaps

NASA Technical Reports Server (NTRS)

Muslimov, Alex G.; Harding, Alice K.

2004-01-01

We explore the pulsar slot gap (SG) electrodynamics up to very high altitudes, where for most relatively rapidly rotating pulsars both the standard small-angle approximation and the assumption that the magnetic field lines are ideal stream lines break down. We address the importance of the electrodynamic conditions at the SG boundaries and the occurrence of a steady-state drift of charged particles across the SG field lines at very high altitudes. These boundary conditions and the cross-field particle motion determine the asymptotic behavior of the scalar potential at all radii from the polar cap (PC) to near the light cylinder. As a result, we demonstrate that the steady-state accelerating electric field, E(sub ll), must approach a small and constant value at high altitude above the PC. This E(sub ll) is capable of maintaining electrons moving with high Lorentz factors (approx. a few x 10(exp 7)) and emitting curvature gamma-ray photons up to nearly the light cylinder. By numerical simulations, we show that primary electrons accelerating from the PC surface to high altitude in the SG along the outer edge of the open field region will form caustic emission patterns on the trailing dipole field lines. Acceleration and emission in such an extended SG may form the physical basis of a model that can successfully reproduce some pulsar high-energy light curves.

Determination of the ground state of an Au-supported FePc film based on the interpretation of Fe K - and L -edge x-ray magnetic circular dichroism measurements

NASA Astrophysics Data System (ADS)

Natoli, Calogero R.; Krüger, Peter; Bartolomé, Juan; Bartolomé, Fernando

2018-04-01

We determine the magnetic ground state of the FePc molecule on Au-supported thin films based on the observed values of orbital anisotropy and spectroscopic x-ray magnetic circular dichroism (XMCD) measurements at the Fe K and L edges. Starting from ab initio molecular orbital multiplet calculations for the isolated molecule, we diagonalize the spin-orbit interaction in the subspace spanned by the three lowest spin triplet states of 3A2 g and 3Eg symmetry in the presence of a saturating magnetic field at a polar angle θ with respect to the normal to the plane of the film, plus an external perturbation representing the effect of the molecules in the stack on the FePc molecule under consideration. We find that the orbital moment of the ground state strongly depends on the magnetic field direction in agreement with the sum rule analysis of the L23-edge XMCD data. We calculate integrals over the XMCD spectra at the Fe K and L23 edges as used in the sum rules and explicitly show that they agree with the expectation values of the orbital moment and effective spin moment of the ground state. On the basis of this analysis, we can rule out alternative candidates proposed in the literature.

An Almost Complete Radio Survey of Magnetic Cataclysmic Variables

NASA Astrophysics Data System (ADS)

Dieck, Christopher A.; Everett Barrett, Paul; Beasley, Anthony J.; Pal Singh, Kulinder; Boboltz, David A.; Godon, Patrick; Mason, Paul A.

2016-01-01

This poster presents the results of a radio survey using the Jansky Very Large Array (JVLA) of 129 Magnetic Cataclysmic Variables (MCVs) north of declination -35 deg. 103 hours of observations were performed during the JVLA observing sessions 2013B and 2015A, when the array was mostly in its highest spatial-resolution configurations (i.e., A and B). Most targets were observed twice for 2-5 minutes at each of three frequencies (C, X, and K-bands), although a few targets were also observed at a fourth frequency (Q-band). 22 of the 129 MCVS were detected at one or more frequencies. Of these 22 detections, 15 are new. This number nearly triples the number of MCVs that are known radio sources. Most detections are at the C and X-band frequencies, although three sources were detected at the K-band frequency. One of the K-band frequency detections is the known rapidly-rotating radio source AE Aqr, while the other two are the polars, AI Tri and ST LMi. Of the 22 detected sources, two-thirds are polars (15) and all are believed to be nearby (<200 pc). Except for a few stronger sources, most detections are in the range of 100-200 µJy, which at a distance of 150 pc corresponds roughly to a luminosity of 2x1024 erg/s at the X-band frequency. The results of this survey are encouraging in that more MCVs are likely to be detected as the time on-source increases, since the flux from MCVs is highly variable.

Atomic-scale understanding of high thermal stability of the Mo/CoFeB/MgO spin injector for spin-injection in remanence.

PubMed

Tao, Bingshan; Barate, Philippe; Devaux, Xavier; Renucci, Pierre; Frougier, Julien; Djeffal, Abdelhak; Liang, Shiheng; Xu, Bo; Hehn, Michel; Jaffrès, Henri; George, Jean-Marie; Marie, Xavier; Mangin, Stéphane; Han, Xiufeng; Wang, Zhanguo; Lu, Yuan

2018-05-31

Remanent spin injection into a spin light emitting diode (spin-LED) at zero magnetic field is a prerequisite for future application of spin optoelectronics. Here, we demonstrate the remanent spin injection into GaAs based LEDs with a thermally stable Mo/CoFeB/MgO spin injector. A systematic study of magnetic properties, polarization-resolved electroluminescence (EL) and atomic-scale interfacial structures has been performed in comparison with the Ta/CoFeB/MgO spin injector. The perpendicular magnetic anisotropy (PMA) of the Mo/CoFeB/MgO injector shows more advanced thermal stability than that of the Ta/CoFeB/MgO injector and robust PMA can be maintained up to 400 °C annealing. The remanent circular polarization (PC) of EL from the Mo capped spin-LED reaches a maximum value of 10% after 300 °C annealing, and even remains at 4% after 400 °C annealing. In contrast, the Ta capped spin-LED almost completely loses the remanent PC under 400 °C annealing. Combined advanced electron microscopy and spectroscopy studies reveal that a large amount of Ta diffuses into the MgO tunneling barrier through the CoFeB layer after 400 °C annealing. However, the diffusion of Mo into CoFeB is limited and never reaches the MgO barrier. These findings afford a comprehensive perspective to use the highly thermally stable Mo/CoFeB/MgO spin injector for efficient electrical spin injection in remanence.

Association between Plasma Ceramides and Phosphatidylcholines and Hippocampal Brain Volume in Late Onset Alzheimer’s Disease

PubMed Central

Kim, Min; Nevado-Holgado, Alejo; Whiley, Luke; Snowden, Stuart G.; Soininen, Hilkka; Kloszewska, Iwona; Mecocci, Patrizia; Tsolaki, Magda; Vellas, Bruno; Thambisetty, Madhav; Dobson, Richard J.B.; Powell, John F.; Lupton, Michelle K.; Simmons, Andy; Velayudhan, Latha; Lovestone, Simon; Proitsi, Petroula; Legido-Quigley, Cristina

2016-01-01

Lipids such as ceramides and phosphatidylcholines (PC) have been found altered in the plasma of Alzheimer’s disease (AD) patients in a number of discovery studies. For this reason, the levels of 6 ceramides and 3 PCs, with different fatty acid length and saturation levels, were measured in the plasma from 412 participants (AD n = 205, Control n = 207) using mass spectrometry coupled with ultra-performance liquid chromatography. After this, associations with AD status, brain atrophy, and age-related effects were studied. In the plasma of AD participants, cross-sectional analysis revealed elevated levels of three ceramides (Cer16:0 p < 0.01, Cer18:0 p < 0.01, Cer24:1 p < 0.05). In addition, two PCs in AD plasma (PC36:5 p < 0.05, PC38:6 p < 0.05) were found to be depleted compared to the control group, with PC36:5 also associating with hippocampal atrophy (p < 0.01). Age-specific analysis further revealed that levels of Cer16:0, Cer18:0, and Cer20:0 were associated with hippocampal atrophy only in younger participants (age < 75, p < 0.05), while all 3 PCs did so in the older participants (age > 75, p < 0.05). PC36:5 was associated with AD status in the younger group (p < 0.01), while PC38:6 and 40:6 did so in the older group (p < 0.05). In this study, elevated ceramides and depleted PCs were found in the plasma from 205 AD volunteers. Our findings also suggest that dysregulation in PC and ceramide metabolism could be occurring in different stages of AD progression. PMID:27911300

CRS-HIPEC Prolongs Survival but is Not Curative for Patients with Peritoneal Carcinomatosis of Gastric Cancer.

PubMed

Boerner, T; Graichen, A; Jeiter, T; Zemann, F; Renner, P; März, L; Soeder, Y; Schlitt, H J; Piso, P; Dahlke, M H

2016-11-01

Peritoneal carcinomatosis (PC) is a dismal feature of gastric cancer that most often is treated by systemic palliative chemotherapy. In this retrospective matched pairs-analysis, we sought to establish whether specific patient subgroups alternatively should be offered a multimodal therapy concept, including cytoreductive surgery (CRS) and intraoperative hyperthermic chemotherapy (HIPEC). Clinical outcomes of 38 consecutive patients treated with gastrectomy, CRS and HIPEC for advanced gastric cancer with PC were compared to patients treated by palliative management (with and without gastrectomy) and to patients with advanced gastric cancer with no evidence of PC. Kaplan-Meier survival curves and multivariate Cox regression models were applied. Median survival time after gastrectomy was similar between patients receiving CRS-HIPEC and matched control patients operated for advanced gastric cancer without PC [18.1 months, confidence interval (CI) 10.1-26.0 vs. 21.8 months, CI 8.0-35.5 months], resulting in comparable 5-year survival (11.9 vs. 12.1 %). The median survival time after first diagnosis of PC for gastric cancer was 17.2 months (CI 10.1-24.2 months) in the CRS-HIPEC group compared with 11.0 months (CI 7.4-14.6 months) for those treated by gastrectomy and chemotherapy alone, resulting in a twofold increase of 2-year survival (35.8 vs. 16.9 %). We provide retrospective evidence that multimodal treatment with gastrectomy, CRS, and HIPEC is associated with improved survival for patients with PC of advanced gastric cancer compared with gastrectomy and palliative chemotherapy alone. We also show that patients treated with CRS-HIPEC have comparable survival to matched control patients without PC. However, regardless of treatment scheme, all patients subsequently recur and die of disease.

Hypoglycaemic activity of culinary Pleurotus ostreatus and P. cystidiosus mushrooms in healthy volunteers and type 2 diabetic patients on diet control and the possible mechanisms of action.

PubMed

Jayasuriya, W J A Banukie N; Wanigatunge, Chandanie A; Fernando, Gita H; Abeytunga, D Thusitha U; Suresh, T Sugandhika

2015-02-01

This study determined the oral hypoglycaemic effect of suspensions of freeze dried and powdered (SFDP) Pleurotus ostreatus (P.o) and Pleurotus cystidiosus (P.c), using healthy human volunteers and Type 2 diabetic patients on diet control at a dose of 50 mg/kg/body weight, followed by a glucose load. The possible hypoglycaemic mechanisms were evaluated using rats, by examining intestinal glucose absorption and serum levels of insulin, glucokinase (GK) and glycogen synthase kinase (GSK). The P.o and P.c showed a significant reduction (P < 0.05) in fasting and postprandial serum glucose levels of healthy volunteers and reduced the postprandial serum glucose levels and increased the serum insulin levels (P < 0.05) of Type 2 diabetic patients. The P.o and P.c increased the intestinal absorption of glucose but simultaneously reduced the serum glucose levels (P < 0.05) in rats. Both mushrooms reduced the serum GSK and promoted insulin secretion while P.c increased serum GK (P < 0.05). The hypoglycaemic activity of P.o and P.c makes mushrooms beneficial functional foods in diabetes mellitus. The mechanism of hypoglycaemic activity of P.o and P.c is possibly by increasing GK activity and promoting insulin secretion and thereby increasing the utilization of glucose by peripheral tissues, inhibiting GSK and promoting glycogen synthesis. Copyright © 2014 John Wiley & Sons, Ltd.

Assessment of Uinta Basin Oil and Natural Gas Well Pad ...

EPA Pesticide Factsheets

In the fall of 2016, a field study was conducted in the Uinta Basin Utah to improve information on oil and natural gas well pad pneumatic controllers (PCs) and emission measurement methods. A total of 80 PC systems at five oil sites (supporting six wells) and three gas sites (supporting 12 wells) were surveyed, and emissions data were produced using a combination of measurements and engineering emission estimates. Ninety-six percent of the PCs surveyed were the low actuation frequency intermittent vent type. The overall whole gas emission rate for the study was estimated at 0.37 scfh with the majority of emissions occurring from three continuous vent PCs (1.0 scfh average) and eleven (14%) malfunctioning intermittent vent PC systems (1.6 scfh average). Oil sites employed, on average 10.3 PC systems per well compared to 1.5 for gas sites. Oil and gas sites had group average PC emission rates of 0.28 scfh and 0.67 scfh, respectively, with this difference due in part to site selection procedures. The PC system types encountered, the engineering emissions estimate approach, and comparisons to measurements are described. Survey methods included identification of malfunctioning PC systems and emission measurements with augmented high volume sampling and installed mass flow meters, each providing a somewhat different picture of emissions that are elucidated through example cases. This paper reports on an oil and natural gas well pad pneumatic controller emissions stud

Chitosan derivatives for gene transfer: effect of phosphorylcholine and diethylaminoethyl grafts on the in vitro transfection efficiency.

PubMed

Picola, Isadora Pfeifer Dalla; Shi, Qin; Fernandes, Júlio Cesar; Petrônio, Maicon Segalla; Lima, Aline Margarete Furuyama; de Oliveira Tiera, Vera Aparecida; Tiera, Marcio José

2016-11-01

The purpose of this work was to improve the functional properties of chitosan for gene transfer by inserting phosphorylcholine (PC) and diethylaminoethyl (DEAE) groups into the main chain. A series of derivatives containing increasing contents of DEAE and a fixed content of PC groups were synthesized and characterized, aiming to evaluate the effect of these groups on the nanoparticles' properties and the in vitro transfection efficiency. The derivatives were soluble at physiological pH levels and all derivatives were less cytotoxic than the control, the lipid lipofectamine. The obtained derivatives complexed pDNA into nanoparticles with smaller sizes and higher zeta potentials than plain chitosan. The in vitro transfection was performed with nanoparticles prepared at pH 6.3 and 7.4 and the results showed that nanoparticles prepared with derivatives containing 20% of PC groups (PC18-CH) and high degrees of substitution by DEAE (PC20-CH-DEAE100, CH-DEAE80, CH-DEAE100) displayed the better transfection efficiencies in HeLa cells, reaching relative values comparable to lipofectamine. The most effective derivative, PC18CH, was selected for complexation with siRNA and its complexes demonstrated an in vitro knockdown efficiency highly dependent on the N/P ratio. Our combined results indicated that, by means of controlled modifications, the limitations of chitosan can be overcome to obtain more effective carriers based on chitosan, and the derivatives here studied hold potential for in vivo studies.

Synergistic interaction between gold nanoparticles and nickel phthalocyanine in layer-by-layer (LbL) films: evidence of constitutional dynamic chemistry (CDC).

PubMed

Alencar, Wagner S; Crespilho, Frank N; Martins, Marccus V A; Zucolotto, Valtencir; Oliveira, Osvaldo N; Silva, Welter C

2009-07-07

The concept of constitutional dynamic chemistry (CDC) based on the control of non-covalent interactions in supramolecular structures is promising for having a large impact on nanoscience and nanotechnology if adequate nanoscale manipulation methods are used. In this study, we demonstrate that the layer-by-layer (LbL) technique may be used to produce electroactive electrodes with ITO coated by tetrasulfonated nickel phthalocyanine (NiTsPc) alternated with poly(allylamine hydrochloride) (PAH) incorporating gold nanoparticles (AuNP), in which synergy has been achieved in the interaction between the nanoparticles and NiTsPc. The catalytic activity toward hydrogen peroxide (H(2)O(2)) in multilayer films was investigated using cyclic voltammetry, where oxidation of H(2)O(2) led to increased currents in the PAH-AuNP/NiTsPc films for the electrochemical processes associated with the phthalocyanine ring and nickel at 0.52 and 0.81 V vs. SCE, respectively, while for PAH/NiTsPc films (without AuNP) only the first redox process was affected. In control experiments we found out that the catalytic activity was not solely due to the presence of AuNP, but rather to the nanoparticles inducing NiTsPc supramolecular structures that favored access to their redox sites, thus yielding strong charge transfer. The combined effects of NiTsPc and AuNP, which could only be observed in nanostructured LbL films, point to another avenue to pursue within the CDC paradigm.

Nuclear reactivity control using laser induced polarization

DOEpatents

Bowman, Charles D.

1991-01-01

A control element for reactivity control of a fission source provides an atomic density of .sup.3 He in a control volume which is effective to control criticality as the .sup.3 He is spin-polarized. Spin-polarization of the .sup.3 He affects the cross section of the control volume for fission neutrons and hence, the reactivity. An irradiation source is directed within the .sup.3 He for spin-polarizing the .sup.3 He. An alkali-metal vapor may be included with the .sup.3 He where a laser spin-polarizes the alkali-metal atoms which in turn, spin-couple with .sup.3 He to spin-polarize the .sup.3 He atoms.

Nuclear reactivity control using laser induced polarization

DOEpatents

Bowman, Charles D.

1990-01-01

A control element for reactivity control of a fission source provides an atomic density of .sup.3 He in a control volume which is effective to control criticality as the .sup.3 He is spin-polarized. Spin-polarization of the .sup.3 He affects the cross section of the control volume for fission neturons and hence, the reactivity. An irradiation source is directed within the .sup.3 He for spin-polarizing the .sup.3 He. An alkali-metal vapor may be included with the .sup.3 He where a laser spin-polarizes the alkali-metal atoms which in turn, spin-couple with .sup.3 He to spin-polarize the .sup.3 He atoms.

Upregulating Apoptotic Signaling in Neurofibromatosis

DTIC Science & Technology

2009-09-01

Schwannoma) cells that are NF1 deficient cells were used. Rat pheochromocytoma PC12 cells were selected as a control, in which Ras signaling is normal. The...Down and Detection kit. The baseline level of GTP bound Ras was detected in PC12 cells (rat pheochromocytoma ) in which Ras signaling is intact. In

Development of a PC interface board for true color control using an Ar Kr white-light laser

NASA Astrophysics Data System (ADS)

Shin, Yongjin; Park, Sohee; Kim, Youngseop; Lee, Jangwoen

2006-06-01

For the optimal laser display, it is crucial to select and control color signals of proper wavelengths in order to construct a wide range of laser display colors. In traditional laser display schemes, color control has been achieved through the mechanical manipulation of red, green, and blue (RGB) laser beam intensities using color filters. To maximize the effect of a laser display and its color contents, it is desirable to generate laser beams with wide selection of wavelengths. We present an innovative laser display control technique, which generates six channel laser wavelengths from a white-light laser using a RF-controlled polychromatic acousto optical modulator (PCAOM). This technique enables us not only to control the intensity of individual channels, but also to achieve true color signals for the laser beam display including RGB, yellow, cyan, and violet (YCV), and other intermediate colors. For the optimal control of the PCAOM and galvano-mirror, we designed and fabricated a PC interface board. Using this PC control, we separated the white-light from an Ar-Kr mixed gas laser into various wavelengths and reconstructed them into different color schemes. Also we demonstrated the effective control and simultaneous display of reconstructed true color laser beams on a flat screen.

A genome-wide association study of IgM antibody against phosphorylcholine: shared genetics and phenotypic relationship to chronic lymphocytic leukemia.

PubMed

Chen, Xu; Gustafsson, Stefan; Whitington, Thomas; Borné, Yan; Lorentzen, Erik; Sun, Jitong; Almgren, Peter; Su, Jun; Karlsson, Robert; Song, Jie; Lu, Yi; Zhan, Yiqiang; Hägg, Sara; Svensson, Per; Smedby, Karin E; Slager, Susan L; Ingelsson, Erik; Lindgren, Cecilia M; Morris, Andrew P; Melander, Olle; Karlsson, Thomas; de Faire, Ulf; Caidahl, Kenneth; Engström, Gunnar; Lind, Lars; Karlsson, Mikael C I; Pedersen, Nancy L; Frostegård, Johan; Magnusson, Patrik K E

2018-05-15

Phosphorylcholine (PC) is an epitope on oxidized low-density lipoprotein (oxLDL), apoptotic cells and several pathogens like Streptococcus pneumoniae. Immunoglobulin M against PC (IgM anti-PC) has the ability to inhibit uptake of oxLDL by macrophages and increase clearance of apoptotic cells. From our genome-wide association studies (GWASs) in four European-ancestry cohorts, six single nucleotide polymorphisms (SNPs) in 11q24.1 were discovered (in 3002 individuals) and replicated (in 646 individuals) to be associated with serum level of IgM anti-PC (the leading SNP rs35923643-G, combined β = 0.19, 95% confidence interval 0.13-0.24, P = 4.3 × 10-11). The haplotype tagged by rs35923643-G (or its proxy SNP rs735665-A) is also known as the top risk allele for chronic lymphocytic leukemia (CLL), and a main increasing allele for general IgM. By using summary GWAS results of IgM anti-PC and CLL in the polygenic risk score (PRS) analysis, PRS on the basis of IgM anti-PC risk alleles positively associated with CLL risk (explained 0.6% of CLL variance, P = 1.2 × 10-15). Functional prediction suggested that rs35923643-G might impede the binding of Runt-related transcription factor 3, a tumor suppressor playing a central role in the immune regulation of cancers. Contrary to the expectations from the shared genetics between IgM anti-PC and CLL, an inverse relationship at the phenotypic level was found in a nested case-control study (30 CLL cases with 90 age- and sex-matched controls), potentially reflecting reverse causation. The suggested function of the top variant as well as the phenotypic association between IgM anti-PC and CLL risk needs replication and motivates further studies.

Histone deacetylase 6 inhibition reduces cysts by decreasing cAMP and Ca2+ in knock-out mouse models of polycystic kidney disease.

PubMed

Yanda, Murali K; Liu, Qiangni; Cebotaru, Valeriu; Guggino, William B; Cebotaru, Liudmila

2017-10-27

Autosomal dominant polycystic kidney disease (ADPKD) is associated with progressive enlargement of multiple renal cysts, often leading to renal failure that cannot be prevented by a current treatment. Two proteins encoded by two genes are associated with ADPKD: PC1 ( pkd1 ), primarily a signaling molecule, and PC2 ( pkd2 ), a Ca 2+ channel. Dysregulation of cAMP signaling is central to ADPKD, but the molecular mechanism is unresolved. Here, we studied the role of histone deacetylase 6 (HDAC6) in regulating cyst growth to test the possibility that inhibiting HDAC6 might help manage ADPKD. Chemical inhibition of HDAC6 reduced cyst growth in PC1-knock-out mice. In proximal tubule-derived, PC1-knock-out cells, adenylyl cyclase 6 and 3 (AC6 and -3) are both expressed. AC6 protein expression was higher in cells lacking PC1, compared with control cells containing PC1. Intracellular Ca 2+ was higher in PC1-knock-out cells than in control cells. HDAC inhibition caused a drop in intracellular Ca 2+ and increased ATP-simulated Ca 2+ release. HDAC6 inhibition reduced the release of Ca 2+ from the endoplasmic reticulum induced by thapsigargin, an inhibitor of endoplasmic reticulum Ca 2+ -ATPase. HDAC6 inhibition and treatment of cells with the intracellular Ca 2+ chelator 1,2-bis(2-aminophenoxy)ethane- N , N , N ', N '-tetraacetic acid tetrakis(acetoxymethyl ester) reduced cAMP levels in PC1-knock-out cells. Finally, the calmodulin inhibitors W-7 and W-13 reduced cAMP levels, and W-7 reduced cyst growth, suggesting that AC3 is involved in cyst growth regulated by HDAC6. We conclude that HDAC6 inhibition reduces cell growth primarily by reducing intracellular cAMP and Ca 2+ levels. Our results provide potential therapeutic targets that may be useful as treatments for ADPKD. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Dietary oregano essential oil alleviates experimentally induced coccidiosis in broilers.

PubMed

Mohiti-Asli, M; Ghanaatparast-Rashti, M

2015-06-15

An experiment was conducted to determine the effects of oregano essential oil on growth performance and coccidiosis prevention in mild challenged broilers. A total of 250 1-d-old chicks were used in a completely randomized design with 5 treatments and 5 replicates with 10 birds in each replication. Experimental treatments included: (1) negative control (NC; unchallenged), (2) positive control (PC; challenged with sporulated oocysts of Eimeria), (3) PC fed 200 ppm Diclazuril in diet, (4) PC fed 300 ppm oregano oil in diet, and (5) PC fed 500 ppm oregano oil in diet. At 22 d of age, all the experimental groups except for NC were challenged with 50-fold dose of Livacox T as a trivalent live attenuated coccidiosis vaccine. On d 28, two birds were slaughtered and intestinal coccidiosis lesions were scored 0-4. Moreover, dropping was scored in the scale of 0-3, and oocysts per gram feces (OPG) were measured. Oregano oil at either supplementation rate increased body weight gain (P=0.039) and improved feed conversion ratio (P=0.010) from d 22 to 28, when compared with PC group. Using 500 ppm oregano oil in challenged broilers diet increased European efficiency factor than PC group (P=0.020). Moreover, challenged broilers fed 500 ppm oregano oil or Diclazuril in diets displayed lower coccidiosis lesions scores in upper (P=0.003) and middle (P=0.018) regions of intestine than PC group, with the effect being similar to unchallenged birds. In general, challenged birds fed 500 ppm oregano oil or Diclazuril in diets had lower OPG (P=0.001), dropping scores (P=0.001), litter scores (P=0.001), and pH of litter (P=0.001) than PC group. It could be concluded that supplementation of oregano oil at the dose of 500 ppm in diet may have beneficial effect on prevention of coccidiosis in broilers. Copyright © 2015 Elsevier B.V. All rights reserved.

Hypnotic Effect of Portulaca oleracea L on Pentobarbital-Induced Sleep in Mice.

PubMed

Hamedi, Shokouhsadat; Forouzanfar, Fatemeh; Rakhshandeh, Hasan; Arian, Amirali

2018-03-08

In Iranian Traditional Medicine, the herbs with cold and wet temperament can help to improve insomnia. Portulaca oleracea has cold and wet temperament, so the present study was carried out to investigate the sleep-prolonging effect of Portulaca oleracea. This work was an experimental study on mice which were randomly divided into these groups: saline (control); Diazepam:) positive control); hydro-alcoholic extract of Portulaca oleracea (12.5, 25, 50, 75 and 100 mg/kg) by Soxhlet apparatus and maceration; in the effective (dose25 mg/kg), different fractions of extract were tested. Ethyl acetate fraction (EAF:); n-Hexane fraction (n-HF); water fraction (WF). All the test compounds were injected intraperitoneally (IP) 30 minutes before pentobarbital administration (30 mg/kg). Duration and latency of pentobarbital-induced sleep were recorded. Also, LD50 of Portulaca oleracea extract was determined and the possible neurotoxicity of the extract was tested on neural PC12 cells. Besides, 30 min after administration of hydro alcoholic extract (HAE) motor coordination (rota-rod test) were assessed. HAE increased the duration of pentobarbital-induced sleep at doses of 25, 50, 75 and 100 mg/kg The hypnotic effect of HAE was comparable to that induced by diazepam. Similarly, WF, EAF, and n-HF at 25 mg/kg could increase sleep duration. The sleep latency was decreased by HAE and NHF but not by WF and EAF. The LD50 value for HAE was found to be 4.8 g/Kg. HAE and its fractions did not show neurotoxic effect in cultured PC12-cell line, also HAE did not affect the animals' performance on the rotarod test. The present data demonstrated that Portulaca oleracea potentiates sleeping behaviors. The main component (s) responsible for the hypnotic effects of this plant is most likely a non-polar agent (s) which is found in n-HF. Isolation of the active constituents may yield a novel sedative drug. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Control of lithium metal anode cycleability by electrolyte temperature

NASA Astrophysics Data System (ADS)

Ishikawa, Masashi; Kanemoto, Manabu; Morita, Masayuki

Precycling of lithium (Li) metal on a nickel substrate at low temperatures (0 and -20°C) in propylene carbonate (PC) mixed with dimethyl carbonate (DMC) and Li hexafluorophosphate (LiPF 6) (LiPF 6-PC/DMC) was found to enhance Li cycleability in the subsequent cycles at a room temperature (25°C). In contrast when the precycling at the low temperatures was performed in PC mixed with 2-methyltetrahydrofuran (2MeTHF) and LiPF 6 (LiPF 6-PC/2MeTHF), no improvement in the Li cycling efficiency was observed in the subsequent cycles at 25°C. These results suggest that the low-temperature precycling effect on the Li cycleability depends on a co-solvent used in the PC-based electrolytes. Ac impedance analysis revealed that the precycling in the low-temperature LiPF 6-PC/DMC electrolyte provided a compact Li interface with a low resistance. In marked constant to this, a Li anode interface formed by the precycling in the LiPF 6-PC/2MeTHF system was irregular and resistive to Li-ion diffusion. The origins of the low-temperature precycling effect dependent on the co-solvents were discussed.

β4-integrin-mediated cytotoxic activity of AexU in human prostate cancer PC3 cells

PubMed Central

KUMANO, MASAFUMI; MIYAKE, HIDEAKI; ABOLGHAIT, SAID K.; BEHNSAWY, HOSNY M.; FUJISAWA, MASATO

2013-01-01

The present study aimed to characterize the cytotoxic activity of AexU, an effector-mediating type three secretion system (TTSS) of gram-negative bacteria, in human prostate cancer cells, focusing on the association with β4-integrin expression. The cytotoxic effects of AexU either alone or in combination with chemotherapeutic agents were evaluated using several human prostate cancer cell lines. Human prostate cancer PC3 cells, in which an expression vector containing siRNA targeting β4-integrin had been introduced, were established (PC3/sh-In), and the cytotoxic effects of AexU on the PC3/sh-In cells were compared with the PC3 cells that were transfected with a control vector (PC3/C). The expression levels of β4-integrin in the PC3 cells were markedly higher compared with those in the LNCaP or DU145 cells, and the cytotoxic effects of AexU in the PC3 cells were more pronounced compared with those in the LNCaP or DU145 cells. The sensitivity of the PC3 cells to docetaxel and cisplatin was significantly enhanced following treatment with AexU, resulting in a decrease in the IC50 of the two agents by ~90%. The cytotoxic effect of AexU in the PC3/C cells was more marked compared with that in the PC3/sh-In cells, and the phosphorylation of Akt in the PC3/C cells appeared to be significantly more inhibited by the treatment with AexU compared with the PC3/sh-In cells. In conclusion, treatment with AexU may be a useful therapeutic option for prostate cancer when β4-integrin is overexpressed. The treatment appears to exert its effects through growth inhibition and by enhancing the sensitivity of the cancer cells to chemotherapeutic agents. PMID:24179545

PC12 Cells Differentiate into Chromaffin Cell-Like Phenotype in Coculture with Adrenal Medullary Endothelial Cells

NASA Astrophysics Data System (ADS)

Mizrachi, Yaffa; Naranjo, Jose R.; Levi, Ben-Zion; Pollard, Harvey B.; Lelkes, Peter I.

1990-08-01

Previously we described specific in vitro interactions between PC12 cells, a cloned, catecholamine-secreting pheochromocytoma cell line derived from the rat adrenal medulla, and bovine adrenal medullary endothelial cells. We now demonstrate that these interactions induce the PC12 cells to acquire physical and biochemical characteristics reminiscent of chromaffin cells. Under coculture conditions involving direct cell-cell contact, the endothelial cells and the PC12 cells reduced their rates of proliferation; upon prolonged coculture PC12 cells clustered into nests of cells similar to the organization of chromaffin cells seen in vivo. Within 3 days in coculture with endothelial cells, but not with unrelated control cells, PC12 cells synthesized increased levels of [Met]enkephalin. In addition, PC12 cells, growing on confluent endothelial monolayers, failed to extend neurites in response to nerve growth factor. Neither medium conditioned by endothelial cells nor fixed endothelial cells could by themselves induce all of these different phenomena in the PC12 cells. These results suggest that under coculture conditions PC12 cells change their state of differentiation toward a chromaffin cell-like phenotype. The rapid, transient increase in the expression of the protooncogene c-fos suggests that the mechanism(s) inducing the change in the state of differentiation in PC12 cells in coculture with the endothelial cells may be distinct from that described for the differentiation of PC12 cells--e.g., by glucocorticoids. We propose that similar interactions between endothelial cells and chromaffin cell precursors may occur during embryonic development and that these interactions might be instrumental for the organ-specific differentiation of the adrenal medulla in vivo.

Lifetime shift work exposure: association with anthropometry, body composition, blood pressure, glucose and heart rate variability.

PubMed

Souza, Breno Bernardes; Monteze, Nayara Mussi; de Oliveira, Fernando Luiz Pereira; de Oliveira, José Magalhães; de Freitas Nascimento, Silvia; Marques do Nascimento Neto, Raimundo; Sales, Maria Lilian; Souza, Gabriela Guerra Leal

2015-03-01

To evaluate the association between lifetime exposure to shift work and blood pressure, fasting glucose (FG), anthropometric variables, body composition and heart rate variability (HRV). Male shift workers (N=438) were evaluated using principal component (PC) analysis. The variables used were: weight, body mass index (BMI), waist circumference (WC), neck circumference (NC), hip circumference (HC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), body fat mass (BFKg), body fat percentage (BF%), visceral fat area (VFA), FG, systolic (SBP) and diastolic blood pressure (DBP), and HRV variables. ECG was performed, extracting heart rate (HR), root mean square of the successive differences (RMSSD), high frequency (HF), low frequency (LF) and the LF/HF ratio. Using linear regression models, the lifetime shift work exposure was associated with each PC. Five PCs were obtained, which accounted for 79.6% of the total variation of the data. PC1 (weight, BMI, WC, NC, HC, WHR, WHtR, BFKg, BF% and VFA) was designated as body obesity; PC2 (HF, RMSSD and LF) as good cardiac regulation; PC3 (SBP and DBP) as blood pressure; PC4 (LF/HF ratio and HR) as bad cardiac regulation and PC5 (WHR and FG) as insulin resistance. After age adjustment, the regression analysis showed that lifetime shift work was negatively associated with PC2 and positively associated with PC3. The association of lifetime shift work exposure with PC2 and PC3 suggests that shift work promotes unfavourable changes in autonomic cardiac control related to a decrease in parasympathetic modulation and an increase in blood pressure. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Evaluation of the internal construct validity of the Personal Care Participation Assessment and Resource Tool (PC-PART) using Rasch analysis.

PubMed

Darzins, Susan; Imms, Christine; Di Stefano, Marilyn; Taylor, Nicholas F; Pallant, Julie F

2014-11-05

The Personal Care Participation Assessment and Resource Tool (PC-PART) is a 43-item, clinician-administered assessment, designed to identify patients' unmet needs (participation restrictions) in activities of daily living (ADL) required for community life. This information is important for identifying problems that need addressing to enable, for example, discharge from inpatient settings to community living. The objective of this study was to evaluate internal construct validity of the PC-PART using Rasch methods. Fit to the Rasch model was evaluated for 41 PC-PART items, assessing threshold ordering, overall model fit, individual item fit, person fit, internal consistency, Differential Item Functioning (DIF), targeting of items and dimensionality. Data used in this research were taken from admission data from a randomised controlled trial conducted at two publically funded inpatient rehabilitation units in Melbourne, Australia, with 996 participants (63% women; mean age 74 years) and with various impairment types. PC-PART items assessed as one scale, and original PC-PART domains evaluated as separate scales, demonstrated poor fit to the Rasch model. Adequate fit to the Rasch model was achieved in two newly formed PC-PART scales: Self-Care (16 items) and Domestic Life (14 items). Both scales were unidimensional, had acceptable internal consistency (PSI =0.85, 0.76, respectively) and well-targeted items. Rasch analysis did not support conventional summation of all PC-PART item scores to create a total score. However, internal construct validity of the newly formed PC-PART scales, Self-Care and Domestic Life, was supported. Their Rasch-derived scores provided interval-level measurement enabling summation of scores to form a total score on each scale. These scales may assist clinicians, managers and researchers in rehabilitation settings to assess and measure changes in ADL participation restrictions relevant to community living. Data used in this research were gathered during a registered randomised controlled trial: Australian and New Zealand Clinical Trials Registry ACTRN12609000973213. Ethics committee approval was gained for secondary analysis of data for this study.

Widespread differential maternal and paternal genome effects on fetal bone phenotype at mid-gestation.

PubMed

Xiang, Ruidong; Lee, Alice M C; Eindorf, Tanja; Javadmanesh, Ali; Ghanipoor-Samami, Mani; Gugger, Madeleine; Fitzsimmons, Carolyn J; Kruk, Zbigniew A; Pitchford, Wayne S; Leviton, Alison J; Thomsen, Dana A; Beckman, Ian; Anderson, Gail I; Burns, Brian M; Rutley, David L; Xian, Cory J; Hiendleder, Stefan

2014-11-01

Parent-of-origin-dependent (epi)genetic factors are important determinants of prenatal development that program adult phenotype. However, data on magnitude and specificity of maternal and paternal genome effects on fetal bone are lacking. We used an outbred bovine model to dissect and quantify effects of parental genomes, fetal sex, and nongenetic maternal effects on the fetal skeleton and analyzed phenotypic and molecular relationships between fetal muscle and bone. Analysis of 51 bone morphometric and weight parameters from 72 fetuses recovered at day 153 gestation (54% term) identified six principal components (PC1-6) that explained 80% of the variation in skeletal parameters. Parental genomes accounted for most of the variation in bone wet weight (PC1, 72.1%), limb ossification (PC2, 99.8%), flat bone size (PC4, 99.7%), and axial skeletal growth (PC5, 96.9%). Limb length showed lesser effects of parental genomes (PC3, 40.8%) and a significant nongenetic maternal effect (gestational weight gain, 29%). Fetal sex affected bone wet weight (PC1, p < 0.0001) and limb length (PC3, p < 0.05). Partitioning of variation explained by parental genomes revealed strong maternal genome effects on bone wet weight (74.1%, p < 0.0001) and axial skeletal growth (93.5%, p < 0.001), whereas paternal genome controlled limb ossification (95.1%, p < 0.0001). Histomorphometric data revealed strong maternal genome effects on growth plate height (98.6%, p < 0.0001) and trabecular thickness (85.5%, p < 0.0001) in distal femur. Parental genome effects on fetal bone were mirrored by maternal genome effects on fetal serum 25-hydroxyvitamin D (96.9%, p < 0.001) and paternal genome effects on alkaline phosphatase (90.0%, p < 0.001) and their correlations with maternally controlled bone wet weight and paternally controlled limb ossification, respectively. Bone wet weight and flat bone size correlated positively with muscle weight (r = 0.84 and 0.77, p < 0.0001) and negatively with muscle H19 expression (r = -0.34 and -0.31, p < 0.01). Because imprinted maternally expressed H19 regulates growth factors by miRNA interference, this suggests muscle-bone interaction via epigenetic factors. © 2014 American Society for Bone and Mineral Research.

Blood metabolite markers of cognitive performance and brain function in aging.

PubMed

Simpson, Brittany N; Kim, Min; Chuang, Yi-Fang; Beason-Held, Lori; Kitner-Triolo, Melissa; Kraut, Michael; Lirette, Seth T; Windham, B Gwen; Griswold, Michael E; Legido-Quigley, Cristina; Thambisetty, Madhav

2016-07-01

We recently showed that Alzheimer's disease patients have lower plasma concentrations of the phosphatidylcholines (PC16:0/20:5; PC16:0/22:6; and PC18:0/22:6) relative to healthy controls. We now extend these findings by examining associations between plasma concentrations of these PCs with cognition and brain function (measured by regional resting state cerebral blood flow; rCBF) in non-demented older individuals. Within the Baltimore Longitudinal Study of Aging neuroimaging substudy, participants underwent cognitive assessments and brain (15)O-water positron emission tomography. Plasma phosphatidylcholines concentrations (PC16:0/20:5, PC16:0/22:6, and PC18:0/22:6), cognition (California Verbal Learning Test (CVLT), Trail Making Test A&B, the Mini-Mental State Examination, Benton Visual Retention, Card Rotation, and Fluencies-Category and Letter), and rCBF were assessed. Lower plasma phosphatidylcholine concentrations were associated with lower baseline memory performance (CVLT long delay recall task-PC16:0/20:5: -2.17-1.39-0.60 p = 0.001 (β with 95% confidence interval subscripts)) and lower rCBF in several brain regions including those associated with memory performance and higher order cognitive processes. Our findings suggest that lower plasma concentrations of PC16:0/20:5, PC16:0/22:6, and PC18:0/22:6 are associated with poorer memory performance as well as widespread decreases in brain function during aging. Dysregulation of peripheral phosphatidylcholine metabolism may therefore be a common feature of both Alzheimer's disease and age-associated differences in cognition. © The Author(s) 2015.

KSC-99pc07

NASA Image and Video Library

1999-01-03

KENNEDY SPACE CENTER, FLA. -- Looking like a Roman candle, the exhaust from the Boeing Delta II rocket with the Mars Polar Lander aboard lights up the clouds as it hurtles skyward. The rocket was launched at 3:21:10 p.m. EST from Launch Complex 17B, Cape Canaveral Air Station. The lander is a solar-powered spacecraft designed to touch down on the Martian surface near the northern-most boundary of the south polar cap, which consists of carbon dioxide ice. The lander will study the polar water cycle, frosts, water vapor, condensates and dust in the Martian atmosphere. It is equipped with a robotic arm to dig beneath the layered terrain. In addition, Deep Space 2 microprobes, developed by NASA's New Millennium Program, are installed on the lander's cruise stage. After crashing into the planet's surface, they will conduct two days of soil and water experiments up to 1 meter (3 feet) below the Martian surface, testing new technologies for future planetary descent probes. The lander is the second spacecraft to be launched in a pair of Mars Surveyor '98 missions. The first is the Mars Climate Orbiter, which was launched aboard a Delta II rocket from Launch Complex 17A on Dec. 11, 1998.

Wide field polarimetry around the Perseus cluster at 350 MHz

NASA Astrophysics Data System (ADS)

Brentjens, M. A.

2011-02-01

Aims: This paper investigates the fascinating diffuse polarization structures at 350 MHz that have previously been tentatively attributed to the Perseus cluster and, more specifically, tries to find out whether the structures are located at (or near) the Perseus cluster, or in the Milky Way. Methods: A wide field, eight point Westerbork Synthesis Radio Telescope mosaic of the area around the Perseus cluster was observed in full polarization. The frequency range was 324 to 378 MHz and the resolution of the polarization maps was 2' × 3'. The maps were processed using Faraday rotation measure synthesis to counter bandwidth depolarization. The RM-cube covers Faraday depths of -384 to +381 rad m-2 in steps of 3 rad m-2. Results: There is emission all over the field at Faraday depths between -50 and +100 rad m-2. All previously observed structures were detected. However, no compelling evidence was found supporting association of those structures with either the Perseus cluster or large scale structure formation gas flows in the Perseus-Pisces super cluster. On the contrary, one of the structures is clearly associated with a Galactic depolarization canal at 1.41 GHz. Another large structure in polarized intensity, as well as Faraday depth at a Faraday depth of +30 rad m-2, coincides with a dark object in WHAM Hα maps at a kinematic distance of 0.5 ± 0.5 kpc. All diffuse polarized emission at 350 MHz towards the Perseus cluster is most likely located within 1 kpc from the Sun. The layers that emit the polarized radiation are less than 40 pc/|B_∥| thick. Appendix is only available in electronic form at http://www.aanda.org

Optical polarization variations in the blazar PKS 1749+096

NASA Astrophysics Data System (ADS)

Uemura, Makoto; Itoh, Ryosuke; Liodakis, Ioannis; Blinov, Dmitry; Nakayama, Masanori; Xu, Longyin; Sawada, Naoko; Wu, Hsiang-Yun; Fujishiro, Issei

2017-12-01

We report on the variation in the optical polarization of the blazar PKS 1749+096 observed in 2008-2015. The degree of polarization (PD) tends to increase in short flares, having a time-scale of a few days. The object favors a polarization angle (PA) of 40°-50° at the flare maxima, which is close to the position angle of the jet (20°-40°). Three clear polarization rotations were detected in the negative PA direction associated with flares. In addition, a rapid and large decrease in the PA was observed in the other two flares, while another two flares showed no large PA variation. The light-curve maxima of the flares possibly tended to lag behind the PD maxima and color-index minima. The PA became -50° to -20° in the decay phase of active states, which is almost perpendicular to the jet position angle. We propose a scenario to explain these observational features, where transverse shocks propagate along curved trajectories. The favored PA at the flare maxima suggests that the observed variations were governed by the variations in the Doppler factor, δ. Based on this scenario, the minimum viewing angle of the source, θ _min = 4.8°-6.6°, and the location of the source, Δr ≳ 0.1 pc, from the central black hole were estimated. In addition, the acceleration of electrons by the shock and synchrotron cooling would have a time-scale similar to that of the change in δ. The combined effect of the variation in δ and acceleration/cooling of electrons is probably responsible for the observed diversity of the polarization variations in the flares.

Perception of control over eating after bariatric surgery for super-obesity--a 2-year follow-up study.

PubMed

Engström, My; Forsberg, Anna; Søvik, Torgeir T; Olbers, Torsten; Lönroth, Hans; Karlsson, Jan

2015-06-01

Physiological and psychosocial factors might contribute to differences in weight loss, eating behaviour and health-related quality of life (HRQoL) after bariatric surgery. The aim of this study was to investigate how perceived control over eating changes after bariatric surgery and whether it affects outcome in super-obese patients. In a retrospective analysis of a prospective study (n = 60), 49 patients were divided into two groups based on eating control 2 years after surgery, as assessed by the Three-Factor Eating Questionnaire-R21 (TFEQ-R21): 29 with good eating control (GC) and 20 patients with poor eating control (group PC). Eating behaviour and generic and condition-specific HRQoL was assessed by questionnaires. There were significant differences in all TFEQ-R21 domains 2 years after surgery in favour of group GC; uncontrolled eating p < 0.001, emotional eating p < 0.001 and for cognitive restraint p = 0.04. The improvement in HRQoL 2 years after surgery was significantly less in group PC compared to group GC in 7 of 8 SF-36 domains (p < 0.05). Mean (SD) percentage of excess body mass index lost was similar between groups, 71.2 (17.8) in group GC versus 65.4 (17.4) in group PC 2 years after surgery (p = 0.27). However, group GC had a significant weight loss between first and second year after surgery (p < 0.001) compared to group PC (p = 0.15). In super-obese patients, perceived poor control over eating 2 years after bariatric surgery was associated with lower HRQoL and more emotional and cognitive restraint eating, than good control overeating.

The Role of C-SRC Activation in Prostate Tumor Progression

DTIC Science & Technology

2006-07-01

cancer cell line PANC -1 and prostrate cancer cell line PC-3 (B2-fold increase relative to control in both cell lines), while the Src inhibitory PP2 blocks...at normoxia in PANC -1 and PC-3 cells, its levels significantly increase in response to hypoxia (B4.5–8-fold induction). Inhibition of endo- genous c...Src activation in PANC -1 and PC-3 cells by PP2 drastically reduced HIF-1a levels to below those levels observed at normoxia (Figure 1a). STAT3 has

Description of the three axis low-g accelerometer package

NASA Technical Reports Server (NTRS)

Amalavage, A. J.; Fikes, E. H.; Berry, E. H.

1978-01-01

The three axis low-g accelerometer package designed for use on the Space Processing Application Rocket (SPAR) Program is described. The package consists of the following major sections: (1) three Kearfott model 2412 accelerometers mounted in an orthogonal triad configuration on a temperature controlled, thermally isolated cube, (2) the accelerometer servoelectronics (printed circuit cards PC-6 through PC-12), and (3) the signal conditioner (printed circuit cards PC-15 and PC-16). The measurement range is 0 + or - 0.031 g with a quantization of 1.1 x 10 to the 7th power g. The package was flown successfully on six SPAR launches with the Black Brant booster. These flights provide approximately 300 s of free fall or zero-g environment.

Association between pancreatitis and subsequent risk of pancreatic cancer: a systematic review of epidemiological studies.

PubMed

Tong, Gui-Xian; Geng, Qing-Qing; Chai, Jing; Cheng, Jing; Chen, Peng-Lai; Liang, Han; Shen, Xing-Rong; Wang, De-Bin

2014-01-01

This study aimed to summarize published epidemiological evidence for the relationship between pancreatitis and subsequent risk of pancreatic cancer (PC). We searched Medline and Embase for epidemiological studies published by February 5th, 2014 examining the risk of PC in pancreatitis patients using highly inclusive algorithms. Information about first author, year of publication, country of study, recruitment period, type of pancreatitis, study design, sample size, source of controls and attained age of subjects were extracted by two researchers and Stata 11.0 was used to perform the statistical analyses and examine publication bias. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated with the random effects model. A total of 17 articles documenting 3 cohort and 14 case-control studies containing 14,667 PC cases and 17,587 pancreatitis cases were included in this study. The pooled OR between pancreatitis and PC risk was 7.05 (95%CI: 6.42-7.75). However, the pooled ORs of case-control and cohort studies were 4.62 (95%CI: 4.08-5.22) and 16.3 (95%CI: 14.3-18.6) respectively. The risk of PC was the highest in patients with chronic pancreatitis (pooled OR=10.35; 95%CI: 9.13-11.75), followed by unspecified type of pancreatitis (pooled OR=6.41; 95%CI: 4.93-8.34), both acute and chronic pancreatitis (pooled OR=6.13; 95%CI: 5.00-7.52), and acute pancreatitis (pooled OR=2.12; 95%CI: 1.59-2.83). The pooled OR of PC in pancreatitis cases diagnosed within 1 year was the highest (pooled OR=23.3; 95%CI: 14.0-38.9); and the risk in subjects diagnosed with pancreatitis for no less than 2, 5 and 10 years were 3.03 (95%CI: 2.41-3.81), 2.82 (95%CI: 2.12-3.76) and 2.25 (95%CI: 1.59-3.19) respectively. Pancreatitis, especially chronic pancreatitis, was associated with a significantly increased risk of PC; and the risk decreased with increasing duration since diagnosis of pancreatitis.

Gluten-free vegan diet induces decreased LDL and oxidized LDL levels and raised atheroprotective natural antibodies against phosphorylcholine in patients with rheumatoid arthritis: a randomized study

PubMed Central

Elkan, Ann-Charlotte; Sjöberg, Beatrice; Kolsrud, Björn; Ringertz, Bo; Hafström, Ingiäld; Frostegård, Johan

2008-01-01

Introduction The purpose of this study was to investigate the effects of vegan diet in patients with rheumatoid arthritis (RA) on blood lipids oxidized low-density lipoprotein (oxLDL) and natural atheroprotective antibodies against phosphorylcholine (anti-PCs). Methods Sixty-six patients with active RA were randomly assigned to either a vegan diet free of gluten (38 patients) or a well-balanced non-vegan diet (28 patients) for 1 year. Thirty patients in the vegan group completed more than 3 months on the diet regimen. Blood lipids were analyzed by routine methods, and oxLDL and anti-PCs were analyzed by enzyme-linked immunosorbent assay. Data and serum samples were obtained at baseline and after 3 and 12 months. Results Mean ages were 50.0 years for the vegan group and 50.8 years for controls. Gluten-free vegan diet induced lower body mass index (BMI) and low-density lipoprotein (LDL) and higher anti-PC IgM than control diet (p < 0.005). In the vegan group, BMI, LDL, and cholesterol decreased after both 3 and 12 months (p < 0.01) and oxLDL after 3 months (p = 0.021) and trendwise after 12 months (p = 0.090). Triglycerides and high-density lipoprotein did not change. IgA anti-PC levels increased after 3 months (p = 0.027) and IgM anti-PC levels increased trendwise after 12 months (p = 0.057). There was no difference in IgG anti-PC levels. In the control diet group, IgM anti-PC levels decreased both after 3 and 12 months (p < 0.01). When separating vegan patients into clinical responders and non-responders at 12 months, the effects on oxLDL and anti-PC IgA were seen only in responders (p < 0.05). Conclusion A gluten-free vegan diet in RA induces changes that are potentially atheroprotective and anti-inflammatory, including decreased LDL and oxLDL levels and raised anti-PC IgM and IgA levels. PMID:18348715

Gluten-free vegan diet induces decreased LDL and oxidized LDL levels and raised atheroprotective natural antibodies against phosphorylcholine in patients with rheumatoid arthritis: a randomized study.

PubMed

Elkan, Ann-Charlotte; Sjöberg, Beatrice; Kolsrud, Björn; Ringertz, Bo; Hafström, Ingiäld; Frostegård, Johan

2008-01-01

The purpose of this study was to investigate the effects of vegan diet in patients with rheumatoid arthritis (RA) on blood lipids oxidized low-density lipoprotein (oxLDL) and natural atheroprotective antibodies against phosphorylcholine (anti-PCs). Sixty-six patients with active RA were randomly assigned to either a vegan diet free of gluten (38 patients) or a well-balanced non-vegan diet (28 patients) for 1 year. Thirty patients in the vegan group completed more than 3 months on the diet regimen. Blood lipids were analyzed by routine methods, and oxLDL and anti-PCs were analyzed by enzyme-linked immunosorbent assay. Data and serum samples were obtained at baseline and after 3 and 12 months. Mean ages were 50.0 years for the vegan group and 50.8 years for controls. Gluten-free vegan diet induced lower body mass index (BMI) and low-density lipoprotein (LDL) and higher anti-PC IgM than control diet (p < 0.005). In the vegan group, BMI, LDL, and cholesterol decreased after both 3 and 12 months (p < 0.01) and oxLDL after 3 months (p = 0.021) and trendwise after 12 months (p = 0.090). Triglycerides and high-density lipoprotein did not change. IgA anti-PC levels increased after 3 months (p = 0.027) and IgM anti-PC levels increased trendwise after 12 months (p = 0.057). There was no difference in IgG anti-PC levels. In the control diet group, IgM anti-PC levels decreased both after 3 and 12 months (p < 0.01). When separating vegan patients into clinical responders and non-responders at 12 months, the effects on oxLDL and anti-PC IgA were seen only in responders (p < 0.05). A gluten-free vegan diet in RA induces changes that are potentially atheroprotective and anti-inflammatory, including decreased LDL and oxLDL levels and raised anti-PC IgM and IgA levels.

Using the AUDIT-PC to predict alcohol withdrawal in hospitalized patients.

PubMed

Pecoraro, Anna; Ewen, Edward; Horton, Terry; Mooney, Ruth; Kolm, Paul; McGraw, Patty; Woody, George

2014-01-01

Alcohol withdrawal syndrome (AWS) occurs when alcohol-dependent individuals abruptly reduce or stop drinking. Hospitalized alcohol-dependent patients are at risk. Hospitals need a validated screening tool to assess withdrawal risk, but no validated tools are currently available. To examine the admission Alcohol Use Disorders Identification Test-(Piccinelli) Consumption (AUDIT-PC) ability to predict the subsequent development of AWS among hospitalized medical-surgical patients admitted to a non-intensive care setting. Retrospective case–control study of patients discharged from the hospital with a diagnosis of AWS. All patients with AWS were classified as presenting with AWS or developing AWS later during admission. Patients admitted to an intensive care setting and those missing AUDIT-PC scores were excluded from analysis. A hierarchical (by hospital unit) logistic regression was performed and receiver-operating characteristics were examined on those developing AWS after admission and randomly selected controls. Because those diagnosing AWS were not blinded to the AUDIT-PC scores, a sensitivity analysis was performed. The study cohort included all patients age ≥18 years admitted to any medical or surgical units in a single health care system from 6 October 2009 to 7 October 2010. After exclusions, 414 patients were identified with AWS. The 223 (53.9 %) who developed AWS after admission were compared to 466 randomly selected controls without AWS. An AUDIT-PC score ≥4 at admission provides 91.0 % sensitivity and 89.7 % specificity (AUC=0.95; 95 % CI, 0.94–0.97) for AWS, and maximizes the correct classification while resulting in 17 false positives for every true positive identified. Performance remained excellent on sensitivity analysis (AUC=0.92; 95 % CI, 0.90–0.93). Increasing AUDIT-PC scores were associated with an increased risk of AWS (OR=1.68, 95 % CI 1.55–1.82, p<0.001). The admission AUDIT-PC score is an excellent discriminator of AWS and could be an important component of future clinical prediction rules. Calibration and further validation on a large prospectivecohort is indicated.