Sample records for potentials ips electron

  1. Equation of motion coupled cluster methods for electron attachment and ionization potential in polyacenes

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

    Bhaskaran-Nair, Kiran; Kowalski, Karol; Jarrell, Mark

    2015-11-05

    Polyacenes have attracted considerable attention due to their use in organic based optoelectronic materials. Polyacenes are polycyclic aromatic hydrocarbons composed of fused benzene rings. Key to understanding and design of new functional materials is an understanding of their excited state properties starting with their electron affinity (EA) and ionization potential (IP). We have developed a highly accurate and com- putationally e*fficient EA/IP equation of motion coupled cluster singles and doubles (EA/IP-EOMCCSD) method that is capable of treating large systems and large basis set. In this study we employ the EA/IP-EOMCCSD method to calculate the electron affinity and ionization potential ofmore » naphthalene, anthracene, tetracene, pentacene, hex- acene and heptacene. We have compared our results with other previous theoretical studies and experimental data. Our EA/IP results are in very good agreement with experiment and when compared with the other theoretical investigations our results represent the most accurate calculations as compared to experiment.« less

  2. Coupled Cluster Studies of Ionization Potentials and Electron Affinities of Single-Walled Carbon Nanotubes

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

    Peng, Bo; Govind, Niranjan; Aprà, Edoardo

    In this paper we apply equation-of-motion coupled cluster (EOMCC) methods in studies of vertical ionization potentials (IP) and electron affinities (EA) for sin- gled walled carbon nanotubes. EOMCC formulations for ionization potentials and electron affinities employing excitation manifolds spanned by single and double ex- citations (IP/EA-EOMCCSD) are used to study IPs and EAs of nanotubes as a function of nanotube length. Several armchair nanotubes corresponding to C20nH20 models with n = 2 - 6 have been used in benchmark calculations. In agreement with previous studies, we demonstrate that the electronegativity of C20nH20 systems remains, to a large extent, independent ofmore » nanotube length. We also compare IP/EA- EOMCCSD results with those obtained with the coupled cluster models with single and double excitations corrected by perturbative triples, CCSD(T), and density func- tional theory (DFT) using global and range-separated hybrid exchange-correlation functionals.« less

  3. Multireference configuration interaction calculations of the first six ionization potentials of the uranium atom

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

    Bross, David H.; Parmar, Payal; Peterson, Kirk A., E-mail: kipeters@wsu.edu

    The first 6 ionization potentials (IPs) of the uranium atom have been calculated using multireference configuration interaction (MRCI+Q) with extrapolations to the complete basis set limit using new all-electron correlation consistent basis sets. The latter was carried out with the third-order Douglas-Kroll-Hess Hamiltonian. Correlation down through the 5s5p5d electrons has been taken into account, as well as contributions to the IPs due to the Lamb shift. Spin-orbit coupling contributions calculated at the 4-component Kramers restricted configuration interaction level, as well as the Gaunt term computed at the Dirac-Hartree-Fock level, were added to the best scalar relativistic results. The final ionizationmore » potentials are expected to be accurate to at least 5 kcal/mol (0.2 eV) and thus more reliable than the current experimental values of IP{sub 3} through IP{sub 6}.« less

  4. Probing ionization potential, electron affinity and self-energy effect on the spectral shape and exciton binding energy of quantum liquid water with self-consistent many-body perturbation theory and the Bethe-Salpeter equation.

    PubMed

    Ziaei, Vafa; Bredow, Thomas

    2018-05-31

    An accurate theoretical prediction of ionization potential (IP) and electron affinity (EA) is key in understanding complex photochemical processes in aqueous environments. There have been numerous efforts in literature to accurately predict IP and EA of liquid water, however with often conflicting results depending on the level of theory and the underlying water structures. In a recent study based on hybrid-non-self-consistent many-body perturbation theory (MBPT) Gaiduk et al (2018 Nat. Commun. 9 247) predicted an IP of 10.2 eV and EA of 0.2 eV, resulting in an electronic band gap (i.e. electronic gap (IP-EA) as measured by photoelectron spectroscopy) of about 10 eV, redefining the widely cited experimental gap of 8.7 eV in literature. In the present work, we show that GW self-consistency and an implicit vertex correction in MBPT considerably affect recently reported EA values by Gaiduk et al (2018 Nat. Commun. 9 247) by about 1 eV. Furthermore, the choice of pseudo-potential is critical for an accurate determination of the absolute band positions. Consequently, the self-consistent GW approach with an implicit vertex correction based on projector augmented wave (PAW) method on top of quantum water structures predicts an IP of 10.2, an EA of 1.1, a fundamental gap of 9.1 eV and an exciton binding (Eb) energy of 0.9 eV for the first absorption band of liquid water via the Bethe-Salpeter equation (BSE). Only within such a self-consistent approach a simultanously accurate prediction of IP, EA, Eg, Eb is possible.

  5. Probing ionization potential, electron affinity and self-energy effect on the spectral shape and exciton binding energy of quantum liquid water with self-consistent many-body perturbation theory and the Bethe–Salpeter equation

    NASA Astrophysics Data System (ADS)

    Ziaei, Vafa; Bredow, Thomas

    2018-05-01

    An accurate theoretical prediction of ionization potential (IP) and electron affinity (EA) is key in understanding complex photochemical processes in aqueous environments. There have been numerous efforts in literature to accurately predict IP and EA of liquid water, however with often conflicting results depending on the level of theory and the underlying water structures. In a recent study based on hybrid-non-self-consistent many-body perturbation theory (MBPT) Gaiduk et al (2018 Nat. Commun. 9 247) predicted an IP of 10.2 eV and EA of 0.2 eV, resulting in an electronic band gap (i.e. electronic gap (IP-EA) as measured by photoelectron spectroscopy) of about 10 eV, redefining the widely cited experimental gap of 8.7 eV in literature. In the present work, we show that GW self-consistency and an implicit vertex correction in MBPT considerably affect recently reported EA values by Gaiduk et al (2018 Nat. Commun. 9 247) by about 1 eV. Furthermore, the choice of pseudo-potential is critical for an accurate determination of the absolute band positions. Consequently, the self-consistent GW approach with an implicit vertex correction based on projector augmented wave (PAW) method on top of quantum water structures predicts an IP of 10.2, an EA of 1.1, a fundamental gap of 9.1 eV and an exciton binding (Eb) energy of 0.9 eV for the first absorption band of liquid water via the Bethe–Salpeter equation (BSE). Only within such a self-consistent approach a simultanously accurate prediction of IP, EA, Eg, Eb is possible.

  6. Multireference configuration interaction calculations of the first six ionization potentials of the uranium atom

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

    Bross, David H.; Parmar, Payal; Peterson, Kirk A.

    The first 6 ionization potentials (IPs) of the uranium atom have been calculated using multireference configuration interaction (MRCI+Q) with extrapolations to the complete basis set (CBS) limit using new all-electron correlation consistent basis sets. The latter were carried out with the third-order Douglas-Kroll-Hess Hamiltonian. Correlation down through the 5s5p5d electrons have been taken into account, as well as contributions to the IPs due to the Lamb shift. Spin-orbit coupling contributions calculated at the 4-component Kramers restricted configuration interaction level, as well as the Gaunt term computed at the Dirac-Hartree-Fock level, were added to the best scalar relativistic results. As amore » result, the final ionization potentials are expected to be accurate to at least 5 kcal/mol (0.2 eV), and thus more reliable than the current experimental values of IP 3 through IP 6.« less

  7. Assessing the role of Hartree-Fock exchange, correlation energy and long range corrections in evaluating ionization potential, and electron affinity in density functional theory.

    PubMed

    Vikramaditya, Talapunur; Lin, Shiang-Tai

    2017-06-05

    Accurate determination of ionization potentials (IPs), electron affinities (EAs), fundamental gaps (FGs), and HOMO, LUMO energy levels of organic molecules play an important role in modeling and predicting the efficiencies of organic photovoltaics, OLEDs etc. In this work, we investigate the effects of Hartree Fock (HF) Exchange, correlation energy, and long range corrections in predicting IP and EA in Hybrid Functionals. We observe increase in percentage of HF exchange results in increase of IPs and decrease in EAs. Contrary to the general expectations inclusion of both HF exchange and correlation energy (from the second order perturbation theory MP2) leads to poor prediction. Range separated Hybrid Functionals are found to be more reliable among various DFT Functionals investigated. DFT Functionals predict accurate IPs whereas post HF methods predict accurate EAs. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  8. Measurement of the first ionization potential of lawrencium, element 103.

    PubMed

    Sato, T K; Asai, M; Borschevsky, A; Stora, T; Sato, N; Kaneya, Y; Tsukada, K; Düllmann, Ch E; Eberhardt, K; Eliav, E; Ichikawa, S; Kaldor, U; Kratz, J V; Miyashita, S; Nagame, Y; Ooe, K; Osa, A; Renisch, D; Runke, J; Schädel, M; Thörle-Pospiech, P; Toyoshima, A; Trautmann, N

    2015-04-09

    The chemical properties of an element are primarily governed by the configuration of electrons in the valence shell. Relativistic effects influence the electronic structure of heavy elements in the sixth row of the periodic table, and these effects increase dramatically in the seventh row--including the actinides--even affecting ground-state configurations. Atomic s and p1/2 orbitals are stabilized by relativistic effects, whereas p3/2, d and f orbitals are destabilized, so that ground-state configurations of heavy elements may differ from those of lighter elements in the same group. The first ionization potential (IP1) is a measure of the energy required to remove one valence electron from a neutral atom, and is an atomic property that reflects the outermost electronic configuration. Precise and accurate experimental determination of IP1 gives information on the binding energy of valence electrons, and also, therefore, on the degree of relativistic stabilization. However, such measurements are hampered by the difficulty in obtaining the heaviest elements on scales of more than one atom at a time. Here we report that the experimentally obtained IP1 of the heaviest actinide, lawrencium (Lr, atomic number 103), is 4.96(+0.08)(-0.07) electronvolts. The IP1 of Lr was measured with (256)Lr (half-life 27 seconds) using an efficient surface ion-source and a radioisotope detection system coupled to a mass separator. The measured IP1 is in excellent agreement with the value of 4.963(15) electronvolts predicted here by state-of-the-art relativistic calculations. The present work provides a reliable benchmark for theoretical calculations and also opens the way for IP1 measurements of superheavy elements (that is, transactinides) on an atom-at-a-time scale.

  9. Benchmark study of ionization potentials and electron affinities of armchair single-walled carbon nanotubes using density functional theory

    NASA Astrophysics Data System (ADS)

    Zhou, Bin; Hu, Zhubin; Jiang, Yanrong; He, Xiao; Sun, Zhenrong; Sun, Haitao

    2018-05-01

    The intrinsic parameters of carbon nanotubes (CNTs) such as ionization potential (IP) and electron affinity (EA) are closely related to their unique properties and associated applications. In this work, we demonstrated the success of optimal tuning method based on range-separated (RS) density functionals for both accurate and efficient prediction of vertical IPs and electron affinities (EAs) of a series of armchair single-walled carbon nanotubes C20n H20 (n  =  2–6) compared to the high-level IP/EA equation-of-motion coupled-cluster method with single and double substitutions (IP/EA-EOM-CCSD). Notably, the resulting frontier orbital energies (–ε HOMO and –ε LUMO) from the tuning method exhibit an excellent approximation to the corresponding IPs and EAs, that significantly outperform other conventional density functionals. In addition, it is suggested that the RS density functionals that possess both a fixed amount of exact exchange in the short-range and a correct long-range asymptotic behavior are suitable for calculating electronic structures of finite-sized CNTs. Next the performance of density functionals for description of various molecular properties such as chemical potential, hardness and electrophilicity are assessed as a function of tube length. Thanks to the efficiency and accuracy of this tuning method, the related behaviors of much longer armchair single-walled CNTs until C200H20 were studied. Lastly, the present work is proved to provide an efficient theoretical tool for future materials design and reliable characterization of other interesting properties of CNT-based systems.

  10. Ionization potential and electron affinity for six common explosive compounds by DFT, MP2, and CBS-QB3

    DOE PAGES

    Cooper, Jason K.; Grant, Christian D.; Zhang, Jin Z.

    2012-07-20

    The vertical and adiabatic ionization potential (IP V and IP A) and vertical electron affinity (EA V) for six explosives (RDX, HMX, TNT, PETN, HMTD, and TATP) have been studied by ab initio computational methods. The IPV was calculated using MP2 and CBS-QB3 while the IP A was calculated with B3LYP, CAM-B3LYP, ω B97XD, B2PLYP, and MP2. RDX and TNT IP A’s were also reported using CBS -QB3. Excluding results by CBS-QB3, B3LYP and B2PLYPD provided superior and more consistent results for calculating the IP. The EA V were calculated using the same methods however B3LYP performed the worst inmore » this case with MP2 and B2PLYPD predicting values closest to those made by CBS-QB3, which was used a reference due to lacking experimental data. Basis set effects were evaluated using 6- 31+G(d,p), 6-311+G(d,p), and 6-311+(3df,2p) for both IP and EA. 6-31+G(d,p) gave satisfactory results for calculating both IP however 6-311+G(3df,2p) had improved results in calculating the EA. The four nitro containing compounds had exothermic reduction potentials while the peroxides were unfavorable. Additionally, it was seen that RDX, HMX, TATP and HMTD were unstable in their reduced forms. Results are aimed to assist detection and screening methods.« less

  11. Electron solvation and localization at interfaces

    NASA Astrophysics Data System (ADS)

    Harris, Charles B.; Szymanski, Paul; Garrett-Roe, Sean; Miller, Andre D.; Gaffney, Kelly J.; Liu, Simon H.; Bezel, Ilya

    2003-12-01

    Two-photon photoemission of thiolate/Ag(111), nitrile/Ag(111), and alcohol/Ag(111) interfaces elucidates electron solvation and localization in two dimensions. For low coverages of thiolates on Ag(111), the occupied (HOMO) and unoccupied (LUMO) electronic states of the sulfer-silver bond are localized due to the lattice gas structure of the adsorbate. As the coverage saturates and the adsorbate-adsorbate nearest neighbor distance decreases, the HOMO and LUMO delocalize across many adsorbate molecules. Alcohol- and nitrile-covered Ag(111) surfaces solvate excess image potential state (IPS) electrons. In the case of alcohol-covered surfaces, this solvation is due to a shift in the local workfunction of the surface. For two-monolayer coverages of nitriles/Ag(111), localization accompanies solvation of the IPS. The size of the localized electron can be estimated by Fourier transformation of the wavefunction from momentum- to position-space. The IPS electron localizes to 15 +/- 4 angstroms full-width at half maximum in the plane of the surface, i.e., to a single lattice site.

  12. Charge transfer excitons and image potential states on organic semiconductor surfaces

    NASA Astrophysics Data System (ADS)

    Yang, Qingxin; Muntwiler, Matthias; Zhu, X.-Y.

    2009-09-01

    We report two types of excited electronic states on organic semiconductor surfaces: image potential states (IPS) and charge transfer excitons (CTE). In the former, an excited electron is localized in the surface-normal direction by the image potential and delocalized in the surface plane. In the latter, the electron is localized in all directions by both the image potential and the Coulomb potential from a photogenerated hole on an organic molecule. We use crystalline pentacene and tetracene surfaces as model systems, and time- and angle-resolved two-photon photoemission spectroscopy to probe the energetics and dynamics of both the IPS and the CTE states. On either pentacene or tetracene surfaces, we observe delocalized image bands and a series of CT excitons with binding energies <0.5eV below the image-band minimum. The binding energies of these CT excitons agree well with solutions to the atomic-H-like Schrödinger equation based on the image potential and the electron-hole Coulomb potential. We hypothesize that the formation of CT excitons should be general to the surfaces of organic semiconductors where the relatively narrow valance-band width facilitates the localization of the hole and the low dielectric constant ensures strong electron-hole attraction.

  13. Impact of electronic healthcare-associated infection surveillance software on infection prevention resources: a systematic review of the literature.

    PubMed

    Russo, P L; Shaban, R Z; Macbeth, D; Carter, A; Mitchell, B G

    2018-05-01

    Surveillance of healthcare-associated infections is fundamental for infection prevention. The methods and practices for surveillance have evolved as technology becomes more advanced. The availability of electronic surveillance software (ESS) has increased, and yet adoption of ESS is slow. It is argued that ESS delivers savings through automation, particularly in terms of human resourcing and infection prevention (IP) staff time. To describe the findings of a systematic review on the impact of ESS on IP resources. A systematic search was conducted of electronic databases Medline and the Cumulative Index to Nursing and Allied Health Literature published between January 1 st , 2006 and December 31 st , 2016 with analysis using the Newcastle-Ottawa Scale. In all, 2832 articles were reviewed, of which 16 studies met the inclusion criteria. IP resources were identified as time undertaken on surveillance. A reduction in IP staff time to undertake surveillance was demonstrated in 13 studies. The reduction proportion ranged from 12.5% to 98.4% (mean: 73.9%). The remaining three did not allow for any estimation of the effect in terms of IP staff time. None of the studies demonstrated an increase in IP staff time. The results of this review demonstrate that adopting ESS yields considerable dividends in IP staff time relating to data collection and case ascertainment while maintaining high levels of sensitivity and specificity. This has the potential to enable reinvestment into other components of IP to maximize efficient use of scarce IP resources. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  14. Ambipolar nature of dimethyl benzo difuran (DMBDF) molecule: A charge transport study

    NASA Astrophysics Data System (ADS)

    Sahoo, Smruti Ranjan; Sahu, Sridhar

    2017-05-01

    We describe a theoretical study of the charge transport properties of the organic dimethyl benzo difuran (DMBDF) molecule based on density functional theory (DFT). Reorganization energy, ionization potential (IP), electron affinity (EA), energy gaps, transfer integral (t) and charge mobility (μ) has been studied to depict the transport properties in the conjugated organic molecules. We computed, large homo transfer integral and IP value leading to high hole mobility (4.46 cm2/V sec). However, the electron reorganization energy (0.34 eV) and the electron mobility of 1.62 cm2/V sec, infers that the DMBDF organic molecule bears an ambipolar character.

  15. The Characteristic Response of Whistler Mode Waves to Interplanetary Shocks

    DOE PAGES

    Yue, Chao; Chen, Lunjin; Bortnik, Jacob; ...

    2017-09-29

    Magnetospheric whistler mode waves play a key role in regulating the dynamics of the electron radiation belts. Recent satellite observations indicate a significant influence of interplanetary (IP) shocks on whistler mode wave power in the inner magnetosphere. In this study, we statistically investigate the response of whistler mode chorus and plasmaspheric hiss to IP shocks based on Van Allen Probes and THEMIS satellite observations. Immediately after the IP shock arrival, chorus wave power is usually intensified, often at postmidnight to prenoon sector, while plasmaspheric hiss wave power predominantly decreases near the dayside but intensifies near the nightside. We conclude thatmore » chorus wave intensification outside the plasmasphere is probably associated with the suprathermal electron flux enhancement caused by the IP shock. Through a simple ray tracing modeling assuming the scenario that plasmaspheric hiss is originated from chorus, we find that the solar wind dynamic pressure increase changes the magnetic field configuration to favor ray penetration in the nightside and promote ray refraction away from the dayside, potentially explaining the magnetic local time–dependent responses of plasmaspheric hiss waves following IP shock arrivals.« less

  16. The Characteristic Response of Whistler Mode Waves to Interplanetary Shocks

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

    Yue, Chao; Chen, Lunjin; Bortnik, Jacob

    Magnetospheric whistler mode waves play a key role in regulating the dynamics of the electron radiation belts. Recent satellite observations indicate a significant influence of interplanetary (IP) shocks on whistler mode wave power in the inner magnetosphere. In this study, we statistically investigate the response of whistler mode chorus and plasmaspheric hiss to IP shocks based on Van Allen Probes and THEMIS satellite observations. Immediately after the IP shock arrival, chorus wave power is usually intensified, often at postmidnight to prenoon sector, while plasmaspheric hiss wave power predominantly decreases near the dayside but intensifies near the nightside. We conclude thatmore » chorus wave intensification outside the plasmasphere is probably associated with the suprathermal electron flux enhancement caused by the IP shock. Through a simple ray tracing modeling assuming the scenario that plasmaspheric hiss is originated from chorus, we find that the solar wind dynamic pressure increase changes the magnetic field configuration to favor ray penetration in the nightside and promote ray refraction away from the dayside, potentially explaining the magnetic local time–dependent responses of plasmaspheric hiss waves following IP shock arrivals.« less

  17. Methemoglobinemia Hemotoxicity of Some Antimalarial 8-Aminoquinoline Analogues and Their Hydroxylated Derivatives: Density Functional Theory Computation of Ionization Potentials.

    PubMed

    Ding, Yuanqing; Liu, Haining; Tekwani, Babu L; Nanayakkara, N P Dhammika; Khan, Ikhlas A; Walker, Larry A; Doerksen, Robert J

    2016-07-18

    The administration of primaquine (PQ), an essential drug for the treatment and radical cure of malaria, can lead to methemoglobin formation and life-threatening hemolysis for glucose-6-phosphate dehydrogenase deficient patients. The ionization potential (IP, a quantitative measure of the ability to lose an electron) of the metabolites generated by antimalarial 8-aminoquinoline (8-AQ) drugs like PQ has been believed to be correlated in part to this methemoglobinemia hemotoxicity: the lower the IP of an 8-AQ derivative, the higher the concentration of methemoglobin generated. In this work, demethoxylated primaquine (AQ02) was employed as a model, by intensive computation at the B3LYP-SCRF(PCM)/6-311++G**//B3LYP/6-31G** level in water, to study the effects of hydroxylation at various positions on the ionization potential. Compared to the parent AQ02, the IPs of AQ02's metabolites hydroxylated at N1', C5, and C7 were lower by 61, 30, and 19 kJ/mol, respectively, while differences in the IP relative to PQ were small for hydroxylation at all other positions. The C6 position, at which the IP of the hydroxylated metabolite was greater than that of AQ02, by 2 kJ/mol, was found to be unique. Several literature and proposed 8-AQ analogues were studied to evaluate substituent effects on their potential to generate methemoglobin, with the finding that hydroxylations at N1' and C5 contribute the most to the potential hemotoxicity of PQ-based antimalarials, whereas hydroxylation at C7 has little effect. Phenoxylation at C5 in PQ-based 8-AQs can block the hydroxylation at C5 and reduce the potential for methemoglobin generation, while -CF3 and chlorines attached to the phenolic ring can further reduce the risk. The H-shift at N1' during the cationization of hydroxylated metabolites of 8-AQs sharply decreased their IPs, but this effect can be significantly reduced by the introduction of an electron-withdrawing group to the quinoline core. The results and this approach may be utilized for the design of safer antimalarial 8-AQ analogues.

  18. Watching Electrons Transfer from Metals to Insulators using Two Photon Photoemission

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

    Johns, James E.

    2010-05-01

    Ultrafast angle-resolved two photon photoemission was used to study the dynamics and interfacial band structure of ultrathin films adsorbed onto Ag(111). Studies focused on the image potential state (IPS) in each system as a probe for measuring changes in electronic behavior in differing environments. The energetics and dynamics of the IPS at the toluene/Ag(111) interface are strongly dependent upon coverage. For a single monolayer, the first IPS is bound by 0.81 eV below the vacuum level and has a lifetime of 50 femtoseconds (fs). Further adsorption of toluene creates islands of toluene with an exposed wetting layer underneath. The IPSmore » is then split into two peaks, one corresponding to the islands and one corresponding to the monolayer. The wetting layer IPS shows the same dynamics as the monolayer, while the lifetime of the islands increases exponentially with increasing thickness. Furthermore, the island IPS transitions from delocalized to localized within 500 fs, and electrons with larger parallel momenta decay much faster. Attempts were made using a stochastic model to extract the rates of localization and intraband cooling at differing momenta. In sexithiophene (6T) and dihexyl-sexithiophene (DH6T), the IPS was used as a probe to see if the nuclear motion of spectating side chains can interfere with molecular conduction. The energy and band mass of the IPS was measured for 6T and two geometries of DH6T on Ag(111). Electrons injected into the thicker coverages of DH6T grew exponentially heavier until they were completely localized by 230 fs, while those injected into 6T remained nearly free electron like. Based off of lifetime arguments and the density of defects, the most likely cause for the mass enhancement of the IPS in this system is small polaron formation caused by coupling of the electron to vibrations of the alkyl substituents. The energetic relaxation of the molecular adsorbate was also measured to be 20 meV/100 fs for the DH6T, and 0 meV/100 fs for the 6T. This relaxation is consistent with the localization of the charge creating a barrier for it moving from one lattice site to a neighboring one. Finally, the IPS was used to study the evolution of the surface band gap at the Mg/Ag(111) interface. The Mg(0001) surface band gap lies 1.6 eV below the Fermi level, and consequently shows no peak in the projected density of states for the IPS. A method for creating layer by layer growth of Mg on Ag(111) was determined using Auger Spectroscopy and low energy electron diffraction. By monitoring the decay of the intensity of the IPS versus coverage, it was determined that four layers of magnesium on Ag(111) is sufficient to completely eliminate the surface band gap« less

  19. Redox routes to substitution of aluminum(III): synthesis and characterization of (IP-)2AlX (IP = α-iminopyridine, X = Cl, Me, SMe, S2CNMe2, C≡CPh, N3, SPh, NHPh).

    PubMed

    Myers, Thomas W; Holmes, Alexandra L; Berben, Louise A

    2012-08-20

    Redox active ligands are shown to facilitate a variety of group transfer reactions at redox inert aluminum(III). Disulfides can be used as a two-electron group transfer reagent, and we show that (IP(-))(2)AlSR can be formed by reaction of [(THF)(6)Na][(IP(2-))(2)Al] (1c) with disulfides RSSR (where X = C(S)NMe(2), 4; SMe, 5). In a more general redox route to substitution of aluminum bis(iminopyridine) complexes, we report zinc(II) salts as a group transfer reagent. Reaction of [((R)IP(2-))(2)Al](-) (R = H, 1c; Me, 1d) with ZnX(2) affords ((R)IP(-))(2)AlX (where IP = iminopyridine, R = H, and X = Cl, 2; CCPh, 6; N(3), 7; SPh, 8; or R = Me and X = NHPh, 9). Single crystal X-ray diffraction analysis of the complexes reveal that each of the five coordinate complexes reported here has a trigonal bipyramidal geometry with τ = 0.668 - 0.858. We observed a correlation between the greatest deviations from ideal trigonal bipyramidal symmetry (lowest τ values), the bond lengths consistent with smallest degree of ligand reduction, and the least polarizable X ligand in (IP(-))(2)AlX. Complex 4 is six-coordinate and is best described as distorted octahedral. Variable temperature magnetic susceptibility measurements indicate that each of the complexes 3-9 has a biradical electronic structure similar to previously reported 2. Magnetic exchange coupling constants in the range J = -94 to -212 cm(-1) were fit to the data for 2-9 to describe the energy of antiferromagnetic interaction between ligand radicals assuming a spin Hamiltonian of the form Ĥ = -2JŜ(L(1))·Ŝ(L(2)). The strongest coupling occurs when the angle between the ligand planes is smallest, presumably to afford good overlap with the Al-X σ* orbital. Electrochemical properties of the complexes were probed using cyclic voltammetry and each of 3-9 displayed a reversible two-electron reduction and two quasi-reversible one-electron oxidation processes. The energy of the ligand based redox processes for 2-9 differ by about 150 mV over all complexes and show a correlation with the degree of IP(-) reduction observed crystallographically; more reduced IP(-) ligands require higher potentials for further reduction. Comproportionation constants that describe the equilibrium for the reaction (IP(-))(2)AlX + (IP)(2)AlX ↔ (IP(-))(IP)AlX fall in the range of K(c) = 10(5.7) to 10(7.9) for 3-9.

  20. Application of Effective Fragment Potential Methos to the Redox Potential of Green Fluorescent Protein

    NASA Astrophysics Data System (ADS)

    Ghosh, Debashree; Krylov, Anna I.

    2011-06-01

    Green fluorescent proteins (GFP) can be considered as a model for flurogenic dyes and are of importance in photovoltaic materials. It exhibits bright green fluorescence when exposed to blue light and has been an extremely powerful tool as non-invasive marker in living cells and extensibly used in molecular and cell biology. The understanding of the underlying electronic structure of these proteins and its chromophore is therefore crucial to the understanding of the mechanism for its optical properties. The chromophore of the GFP is p-hydroxybenzylidene-imidazolinone (HBDI) and is embedded in the center of the β barrel of the GFP. Calculating redox potential of this chromophore is a challenging problem, especially in diverse solvents and protein environment. It is possible to carry out high-level accurate ab-initio calculation of ionization potential or electron affinity of the microsolvated chromophore or the bare chromophore. But, it is not possible to extend these calculations to bulk solvents due to the high computational cost. Effective fragment potential (EFP)[1,2] method gives us a convenient tool to understand such systems. In our work, we have benchmarked the ionization energy and electron affinity of the microsolvated GFP chromophore calculated by combined EOM-IP-CCSD/EFP and EOM-EA-CCSD/EFP with the EOM-IP-CCSD and EOM-EA-CCSD calculations of the oxidized and reduced forms. We have carried out similar EFP-EOM-IP-CCSD and EFP-EOM-EA-CCSD calculations of ionization potential and electron affinity of GFP choromophore in bulk solvent generated by ab-initio molecular dynamics simulations. [1] M. S. Gordon, L. Slipchenko, H. Li, J. H. Jensen, Annual Reports in Computational Chemistry, Volume 3, 177 (2007). [2] D. Ghosh, D. Kosenkov, V. Vanovschi, C.F. Williams, J.M. Herbert, M.S. Gordon, M.W. Schmidt, L.V. Slipchenko, and A.I. Krylov, J. Phys. Chem. A 114, 12739 (2010).

  1. Calibration of imaging plates to electrons between 40 and 180 MeV

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

    Rabhi, N., E-mail: nesrine.rabhi@celia.u-bordeaux.fr; Batani, D.; Boutoux, G.

    2016-05-15

    This paper presents the response calibration of Imaging Plates (IPs) for electrons in the 40-180 MeV range using laser-accelerated electrons at Laboratoire d’Optique Appliquée (LOA), Palaiseau, France. In the calibration process, the energy spectrum and charge of electron beams are measured by an independent system composed of a magnetic spectrometer and a Lanex scintillator screen used as a calibrated reference detector. It is possible to insert IPs of different types or stacks of IPs in this spectrometer in order to detect dispersed electrons simultaneously. The response values are inferred from the signal on the IPs, due to an appropriate chargemore » calibration of the reference detector. The effect of thin layers of tungsten in front and/or behind IPs is studied in detail. GEANT4 simulations are used in order to analyze our measurements.« less

  2. Improved Confinement by Edge Multi-pulse Turbulent Heating on HT-6M Tokamak

    NASA Astrophysics Data System (ADS)

    Mao, Jian-shan; Luo, Jia-rong; Li, Jian-gang; Pan, Yuan; Wang, Mao-quan; Liu, Bao-hua; Wan, Yuan-xi; Li, Qiang; Wu, Xin-chao; Liang, Yun-feng; Xu, Yu-hong; Yu, Chang-xuan

    1997-10-01

    In the recent experiment on HT-6M tokamak, an improved ohmic confinement phase has been observed after application of the edge multi-pulse turbulent heating, and variance of plasma current ΔIp/Ip is about 14-20%. The improved edge plasma confinement phase is characterized by (a) increased average electron density bar Ne and electron temperature Te; (b) reduced Hα radiation from the edge; (c) steeper density and temperature profiles at the edge; (d) a more negative radial electric field over a region of ~ 5 mm deep inside the limiter; (e) a deeper electrostatic potential well at the edge; (f) reduced magnetic fluctuations at the edge.

  3. Ionization Injection of Electrons into a Plasma Wakefield Accelerator at FACET

    NASA Astrophysics Data System (ADS)

    Clayton, Chris; E-200 At Facet Collaboration

    2013-10-01

    In the PWFA experiments at FACET, a low ionization-potential (IP) metal vapor gas (Li) is confined within a heat-pipe oven by a higher IP buffer gas (typically He). The Li is easily field-ionized by the FACET beam. A non-linear wake is formed in the blowout regime when the 20.3 GeV bunch containing 2e10 electrons in a σz ~ 30 μm is focused to a (vacuum) σr < 25 near the ~ 10cm-long boundary region. There the Li density rises from zero up to the oven's 30cm-long flat-topped density of 2.5e17 cm-3. To obtain a mono-energetic beam from accelerated ionization-injected electrons at the far end of the oven--the goal of this experiment--it is necessary for the FACET beam to have a betatron pinch just where the flat-topped region begins; i.e., where the wake wavelength is no longer changing. If the buffer gas contains a mixture of He and a moderate IP gas, the ``impurity'' gases will also be field ionized and potentially contribute more charge to the injected bunch than with He alone. Moderate IP gases were added to the He buffer gas: 10%, 20%, and 50% Ar (balance He) and 30% Ne (balance He) have been used. Evidence for ionization injection and acceleration appears through the observation of distinct features, characterized by their very narrow size and thus angular spread, at the image plane of a magnetic imaging spectrometer. Analysis aimed at characterizing these features with respect to energy, charge, and angular spread is underway and will be presented. This work was supported by the DOE and the NSF.

  4. Direct Delta-MBPT(2) method for ionization potentials, electron affinities, and excitation energies using fractional occupation numbers

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

    Beste, Ariana; Vazquez-Mayagoitia, Alvaro; Ortiz, J. Vincent

    2013-01-01

    A direct method (D-Delta-MBPT(2)) to calculate second-order ionization potentials (IPs), electron affinities (EAs), and excitation energies is developed. The Delta-MBPT(2) method is defined as the correlated extension of the Delta-HF method. Energy differences are obtained by integrating the energy derivative with respect to occupation numbers over the appropriate parameter range. This is made possible by writing the second-order energy as a function of the occupation numbers. Relaxation effects are fully included at the SCF level. This is in contrast to linear response theory, which makes the D-Delta-MBPT(2) applicable not only to single excited but also higher excited states. We showmore » the relationship of the D-Delta-MBPT(2) method for IPs and EAs to a second-order approximation of the effective Fock-space coupled-cluster Hamiltonian and a second-order electron propagator method. We also discuss the connection between the D-Delta-MBPT(2) method for excitation energies and the CIS-MP2 method. Finally, as a proof of principle, we apply our method to calculate ionization potentials and excitation energies of some small molecules. For IPs, the Delta-MBPT(2) results compare well to the second-order solution of the Dyson equation. For excitation energies, the deviation from EOM-CCSD increases when correlation becomes more important. When using the numerical integration technique, we encounter difficulties that prevented us from reaching the Delta-MBPT(2) values. Most importantly, relaxation beyond the Hartree Fock level is significant and needs to be included in future research.« less

  5. Identifying Effectiveness Criteria for Internet Payment Systems.

    ERIC Educational Resources Information Center

    Shon, Tae-Hwan; Swatman, Paula M. C.

    1998-01-01

    Examines Internet payment systems (IPS): third-party, card, secure Web server, electronic token, financial electronic data interchange (EDI), and micropayment based. Reports the results of a Delphi survey of experts identifying and classifying IPS effectiveness criteria and classifying types of IPS providers. Includes the survey invitation letter…

  6. Observation of Image Potential State in Oxygen Intercalated Graphene on Iridium by Two-Photon-Photoemission Spectroscopy

    NASA Astrophysics Data System (ADS)

    Lin, Yi; Li, Yunzhe; Sadowski, Jerzy; Dadap, Jerry; Jin, Wencan; Osgood, Richard

    In this talk, we report our experimental results on the first direct observation of image potential state (IPS) in oxygen-intercalated graphene on iridium by two-photo-photoemission spectroscopy. We demonstrate how oxygen intercalation influences the IPS in Gr/Ir and decouples the interlayer interaction. We present measurements of the electronic dispersion and work function in pristine Gr/Ir, oxygen-intercalated Gr/O/Ir, and deintercalated Gr/Ir. LEED patterns are measured during the pristine, oxygen-intercalated, and deintercalated phases of the Gr/Ir sample. Based on these measurements, relative to the pristine case, the work function and the energy location of n =1 IPS relative to the Fermi level increases by 0.39 eV and 0.3 eV, respectively, due to oxygen intercalation, whereas the effective mass of n =1 IPS is hardly influenced by the intercalation process. Moreover, we achieve the quenching and restoration of the resonance from Ir Rashba states to n =1 IPS in Gr/Ir by oxygen intercalation and deintercalation. This work was supported by the DOE, Office of Basic Energy Sciences, Division of MSE under Contract No. DE-FG 02-04-ER-46157. This research used resources of the CFN, which is the U.S. DOE Office of Science User Facility, under Contract No. DE-SC0012704.

  7. Laser phase control of high-order harmonic generation at large internuclear distance: the H+ -H2+ system.

    PubMed

    Bandrauk, André D; Barmaki, Samira; Kamta, Gerard Lagmago

    2007-01-05

    Exact (Born-Oppenheimer) 3-D numerical solutions of the time-dependent Schrödinger equation are obtained for the one electron linear H+-H2+ atom-molecule system at large internuclear distance R in interaction with two-cycles intense (I>10(14) W cm(-2)) 800 nm laser pulses. High-order harmonic generation (HHG) spectra are obtained with an energy cutoff larger than the atomic maximum of I(p)+3U(p), where I(p) is the ionization potential and U(p) is the ponderomotive energy. At large R, this extended cutoff is shown to be related to the nature of electron transfer, whose direction is shown to depend critically on the carrier-envelope phase (CEP) of the ultrashort pulse. Constructive and destructive interferences in the HHG spectrum resulting from coherent superpositions of electronic states in the H+-H2+ system are interpreted in terms of multiple electron trajectories extracted from a time profile analysis.

  8. Study of imaging plate detector sensitivity to 5-18 MeV electrons

    NASA Astrophysics Data System (ADS)

    Boutoux, G.; Rabhi, N.; Batani, D.; Binet, A.; Ducret, J.-E.; Jakubowska, K.; Nègre, J.-P.; Reverdin, C.; Thfoin, I.

    2015-11-01

    Imaging plates (IPs) are commonly used as passive detectors in laser-plasma experiments. We calibrated at the ELSA electron beam facility (CEA DIF) the five different available types of IPs (namely, MS-SR-TR-MP-ND) to electrons from 5 to 18 MeV. In the context of diagnostic development for the PETawatt Aquitaine Laser (PETAL), we investigated the use of stacks of IP in order to increase the detection efficiency and get detection response independent from the neighboring materials such as X-ray shielding and detector supports. We also measured fading functions in the time range from a few minutes up to a few days. Finally, our results are systematically compared to GEANT4 simulations in order to provide a complete study of the IP response to electrons over the energy range relevant for PETAL experiments.

  9. Density functional theory study on the ionization potentials and electron affinities of thymine-formamide complexes

    NASA Astrophysics Data System (ADS)

    Sun, Haitao; Tang, Ke; Li, Yanmin; Su, Chunfang; Zhou, Zhengyu; Wang, Zhizhong

    The effect of hydrogen bond interactions on ionization potentials (IPs) and electron affinities (EAs) of thymine-formamide complexes (T-F) have been investigated employing the density functional theory B3LYP at 6-311++G(d, p) basis set level. All complexes experience a geometrical change on either electron detachment or attachment, and the change might be facilitated or hindered according to the strength of the hydrogen-bonding interaction involved. The strength of hydrogen bonds presents an opposite changing trend on the two processes. A more important role that H-bonding interaction plays in the process of electron attachment than in the process of electron detachment can be seen by a comparison of the IPs and EAs of complexes with that of isolated thymine. Futhermore, the EAs of isolated thymine are in good agreement with the experimental values (AEA is 0.79 eV, VEA is -0.29 eV [Wetmore et al., Chem Phys Lett 2000, 322, 129]). The calculated total NPA charge distributions reveal that nearly all the negative charges locate on thymine monomer in the anions and even in the cationic states, there are a few negative charges on thymine monomer. An analysis of dissociation energies predicts the processes T-F+→ T++ F and T-F- → T- + F to be the most energetically favorable for T-F+ and T-F-, respectively. Content:text/plain; charset="UTF-8"

  10. Structures and electronic states of halogen-terminated graphene nano-flakes

    NASA Astrophysics Data System (ADS)

    Tachikawa, Hiroto; Iyama, Tetsuji

    2015-12-01

    Halogen-functionalized graphenes are utilized as electronic devices and energy materials. In the present paper, the effects of halogen-termination of graphene edge on the structures and electronic states of graphene flakes have been investigated by means of density functional theory (DFT) method. It was found that the ionization potential (Ip) and electron affinity of graphene (EA) are blue-shifted by the halogen termination, while the excitation energy is red-shifted. The drastic change showed a possibility as electronic devices such as field-effect transistors. The change of electronic states caused by the halogen termination of graphene edge was discussed on the basis of the theoretical results.

  11. Prompt Injections of Highly Relativistic Electrons Induced by Interplanetary Shocks: A Statistical Study of Van Allen Probes Observations

    NASA Technical Reports Server (NTRS)

    Schiller, Q.; Kanekal, S. G.; Jian, L. K,; Li, X.; Jones, A.; Baker, D. N.; Jaynes, A.; Spence, H. E.

    2016-01-01

    We conduct a statistical study on the sudden response of outer radiation belt electrons due to interplanetary (IP) shocks during the Van Allen Probes era, i.e., 2012 to 2015. Data from the Relativistic Electron-Proton Telescope instrument on board Van Allen Probes are used to investigate the highly relativistic electron response (E greater than 1.8 MeV) within the first few minutes after shock impact. We investigate the relationship of IP shock parameters, such as Mach number, with the highly relativistic electron response, including spectral properties and radial location of the shock-induced injection. We find that the driving solar wind structure of the shock does not affect occurrence for enhancement events, 25% of IP shocks are associated with prompt energization, and 14% are associated with MeV electron depletion. Parameters that represent IP shock strength are found to correlate best with highest levels of energization, suggesting that shock strength may play a key role in the severity of the enhancements. However, not every shock results in an enhancement, indicating that magnetospheric preconditioning may be required.

  12. Quantum information processing with trapped electrons and superconducting electronics (Open Access, Publisher’s Version)

    DTIC Science & Technology

    2013-07-05

    This content has been downloaded from IOPscience. Please scroll down to see the full text. Download details: IP Address: 198.81.129.186 This content...structures with a quadratic nonlinearity, i.e. electrodes with a quadrupolar potential. The pump for this parametric coupling process is a classical...approximation. The system operates as a parametric frequency converter, with the classical drive providing pump photons which allow coherent coupling between

  13. Structural, electronic and vibrational properties of GexCy (x+y=2-5) nanoclusters: A B3LYP-DFT study

    NASA Astrophysics Data System (ADS)

    Goswami, Sohini; Saha, Sushmita; Yadav, R. K.

    2015-11-01

    An ab-initio study of the stability, structural and electronic properties has been made for 84 germanium carbide nanoclusters, GexCy (x+y=2-5). The configuration possessing the maximum value of final binding energy (FBE), among the various configurations corresponding to a fixed x+y=n value, is named as the most stable structure. The vibrational and optical properties have been investigated only for the most stable structures. A B3LYP-DFT/6-311G(3df) method has been employed to optimize fully the geometries of the nanoclusters. The binding energies (BE), highest-occupied and lowest-unoccupied molecular orbital (HOMO-LUMO) gaps have been obtained for all the clusters and the bond lengths have been reported for the most stable clusters. We have considered the zero point energy (ZPE) corrections. The adiabatic and vertical ionization potentials (IPs) and electron affinities (EAs), charge on atoms, dipole moments, vibrational frequencies, infrared intensities (IR Int.), relative infrared intensities (Rel. IR Int.) and Raman scattering activities have also been investigated for the most stable structures. The configurations containing the carbon atoms in majority are seen to be the most stable structures. The strong C-C bond has important role in stabilizing the clusters. For the clusters containing one germanium atom and all the other as carbon atoms, the BE increases monotonically with the number of the carbon atoms. The HOMO-LUMO gap, IPs and EAs fluctuates with increase in the number of atoms. The nanoclusters containing even number of carbon atoms have large HOMO-LUMO gaps and IPs, whereas the nanoclusters containing even number of carbon atoms have small EAs. In general, the adiabatic IP (EA) is smaller (greater) than the vertical IP (EA). The optical absorption spectrum or electron energy loss spectrum (EELS) is unique for every cluster, and may be used to characterize a specific cluster. All the predicted physical quantities are in good agreement with the experimental data wherever available. The growth of these most stable structures should be possible in the experiments.

  14. Conjugated polymer energy level shifts in lithium-ion battery electrolytes.

    PubMed

    Song, Charles Kiseok; Eckstein, Brian J; Tam, Teck Lip Dexter; Trahey, Lynn; Marks, Tobin J

    2014-11-12

    The ionization potentials (IPs) and electron affinities (EAs) of widely used conjugated polymers are evaluated by cyclic voltammetry (CV) in conventional electrochemical and lithium-ion battery media, and also by ultraviolet photoelectron spectroscopy (UPS) in vacuo. By comparing the data obtained in the different systems, it is found that the IPs of the conjugated polymer films determined by conventional CV (IPC) can be correlated with UPS-measured HOMO energy levels (EH,UPS) by the relationship EH,UPS = (1.14 ± 0.23) × qIPC + (4.62 ± 0.10) eV, where q is the electron charge. It is also found that the EAs of the conjugated polymer films measured via CV in conventional (EAC) and Li(+) battery (EAB) media can be linearly correlated by the relationship EAB = (1.07 ± 0.13) × EAC + (2.84 ± 0.22) V. The slopes and intercepts of these equations can be correlated with the dielectric constants of the polymer film environments and the redox potentials of the reference electrodes, as modified by the surrounding electrolyte, respectively.

  15. The IP vs. VDE competition as a key factor determining the stability of the MgBX 5 (X = F, Cl) compounds

    NASA Astrophysics Data System (ADS)

    Sikorska, Celina; Skurski, Piotr

    2010-11-01

    The explanation of the MgBX 5 (X = F, Cl) systems existence and stability is provided on the basis of theoretical considerations supported by ab initio calculations. The equilibrium structures and most probable fragmentation processes of 26 (including isomers) MgBX 5 molecules and six OBX 5 compounds (for comparison) were examined and discussed. The competition between the ionization potential (IP) of the MgX subunit and the electron binding energy (VDE) of the BX 4 fragment was found to be the key factor determining the ability to form a stable compound of MgBX 5 type.

  16. Concepts relating magnetic interactions, intertwined electronic orders, and strongly correlated superconductivity

    PubMed Central

    Davis, J. C. Séamus; Lee, Dung-Hai

    2013-01-01

    Unconventional superconductivity (SC) is said to occur when Cooper pair formation is dominated by repulsive electron–electron interactions, so that the symmetry of the pair wave function is other than an isotropic s-wave. The strong, on-site, repulsive electron–electron interactions that are the proximate cause of such SC are more typically drivers of commensurate magnetism. Indeed, it is the suppression of commensurate antiferromagnetism (AF) that usually allows this type of unconventional superconductivity to emerge. Importantly, however, intervening between these AF and SC phases, intertwined electronic ordered phases (IP) of an unexpected nature are frequently discovered. For this reason, it has been extremely difficult to distinguish the microscopic essence of the correlated superconductivity from the often spectacular phenomenology of the IPs. Here we introduce a model conceptual framework within which to understand the relationship between AF electron–electron interactions, IPs, and correlated SC. We demonstrate its effectiveness in simultaneously explaining the consequences of AF interactions for the copper-based, iron-based, and heavy-fermion superconductors, as well as for their quite distinct IPs. PMID:24114268

  17. A computational investigation on the antioxidant potential of myricetin 3,4'-di-O-α-L-rhamnopyranoside.

    PubMed

    Mendes, Rodrigo A; Almeida, Shawan K C; Soares, Iuri N; Barboza, Cristina A; Freitas, Renato G; Brown, Alex; de Souza, Gabriel L C

    2018-05-11

    In this work, we present a computational study on the antioxidant potential of myricetin 3,4[Formula: see text]-di-O-α-L-rhamnopyranoside (Compound M). A density functional theory (DFT) approach with the B3LYP and LC-ωPBE functionals and with both the 6-311G(d,p) and 6-311+G(d,p) basis sets was used. The focus of the investigation was on the structural and energetic parameters including both bond dissociation enthalpies (BDEs) and ionization potentials (IPs), which provide information on the potential antioxidant activity. The properties computed were compared with BDEs and IPs available in the literature for myricetin, a compound well known for presenting antioxidant activity (and the parent molecule of the compound of interest in the present work). Myricetin 3,4[Formula: see text]-di-O-α-L-rhamnopyranoside presented the lowest BDE to be 79.13 kcal/mol (as determined using B3LYP/6-311G(d,p) in water) while myricetin has a quite similar value (within 3.4 kcal/mol). IPs computed in the gas phase [B3LYP/6-311G(d,p)] are 157.18 and 161.4 kcal/mol for myricetin 3,4[Formula: see text]-di-O-α-L-rhamnopyranoside and myricetin, respectively. As the values of BDEs are considerably lower than the ones probed for IPs (in the gas phase or in any given solvent environment), the hydrogen atom transfer mechanism is preferred over the single electron transfer mechanism. The BDEs obtained suggest that myricetin 3,4[Formula: see text]-di-O-α-L-rhamnopyranoside can present antioxidant potential as good as the parent molecule myricetin (a well-known antioxidant). Therefore, experimental tests on the antioxidant activity of Compound M are encouraged.

  18. First-principles real-space study of electronic and optical excitations in rutile TiO 2 nanocrystals

    DOE PAGES

    Hung, Linda; Baishya, Kopinjol; Öğüt, Serdar

    2014-10-17

    We model rutile titanium dioxide nanocrystals (NCs) up to ~1.5 nm in size to study the effects of quantum confinement on their electronic and optical properties. Ionization potentials (IPs) and electron affinities (EAs) are obtained via the perturbative GW approximation (G 0W 0) and ΔSCF method for NCs up to 24 and 64 TiO 2 formula units, respectively. These demanding GW computations are made feasible by using a real-space framework that exploits quantum confinement to reduce the number of empty states needed in GW summations. Time-dependent density functional theory (TDDFT) is used to predict the optical properties of NCs upmore » to 64 TiO 2 units. For a NC containing only 2 TiO 2 units, the offsets of the IP and the EA from the corresponding bulk limits are of similar magnitude. However, as NC size increases, the EA is found to converge more slowly to the bulk limit than the IP. The EA values computed at the G 0W 0 and ΔSCF levels of theory are found to agree fairly well with each other, while the IPs computed with ΔSCF are consistently smaller than those computed with G 0W 0 by a roughly constant amount. TDDFT optical gaps exhibit weaker size dependence than GW quasiparticle gaps, and result in exciton binding energies on the order of eV. Finally, altering the dimensions of a fixed-size NC can change electronic and optical excitations up to several tenths of an eV. The largest NCs modeled are still quantum confined and do not yet have quasiparticle levels or optical gaps at bulk values. Nevertheless, we find that classical Mie-Gans theory can quite accurately reproduce the line shape of TDDFT absorption spectra, even for (anisotropic) TiO 2 NCs of subnanometer size.« less

  19. First-principles real-space study of electronic and optical excitations in rutile TiO2 nanocrystals

    NASA Astrophysics Data System (ADS)

    Hung, Linda; Baishya, Kopinjol; Ã-ǧüt, Serdar

    2014-10-01

    We model rutile titanium dioxide nanocrystals (NCs) up to ˜1.5 nm in size to study the effects of quantum confinement on their electronic and optical properties. Ionization potentials (IPs) and electron affinities (EAs) are obtained via the perturbative GW approximation (G0W0) and ΔSCF method for NCs up to 24 and 64 TiO2 formula units, respectively. These demanding GW computations are made feasible by using a real-space framework that exploits quantum confinement to reduce the number of empty states needed in GW summations. Time-dependent density functional theory (TDDFT) is used to predict the optical properties of NCs up to 64 TiO2 units. For a NC containing only 2 TiO2 units, the offsets of the IP and the EA from the corresponding bulk limits are of similar magnitude. However, as NC size increases, the EA is found to converge more slowly to the bulk limit than the IP. The EA values computed at the G0W0 and ΔSCF levels of theory are found to agree fairly well with each other, while the IPs computed with ΔSCF are consistently smaller than those computed with G0W0 by a roughly constant amount. TDDFT optical gaps exhibit weaker size dependence than GW quasiparticle gaps, and result in exciton binding energies on the order of eV. Altering the dimensions of a fixed-size NC can change electronic and optical excitations up to several tenths of an eV. The largest NCs modeled are still quantum confined and do not yet have quasiparticle levels or optical gaps at bulk values. Nevertheless, we find that classical Mie-Gans theory can quite accurately reproduce the line shape of TDDFT absorption spectra, even for (anisotropic) TiO2 NCs of subnanometer size.

  20. Carbazole/triarylamine based polymers as a hole injection/transport layer in organic light emitting devices.

    PubMed

    Wang, Hui; Ryu, Jeong-Tak; Kwon, Younghwan

    2012-05-01

    This study examined the influence of the charge injection barriers on the performance of organic light emitting diodes (OLEDs) using polymers with a stepwise tuned ionization potential (I(p) approximately -5.01 - -5.29 eV) between the indium tin oxide (ITO) (phi approximately -4.8 eV) anode and tris(8-hydroxyquinolinato) aluminium (Alq3) (I(p) approximately -5.7 eV) layer. The energy levels of the polymers were tuned by structural modification. Double layer devices were fabricated with a configuration of ITO/polymer/Alq3/LiF/Al, where the polymers, Alq3, and LiF/Al were used as the hole injection/transport layer, emissive electron transport layer, and electron injection/cathode, respectively. Using the current density-voltage (J-V), luminescence-voltage (L-V) and efficiencies in these double layer devices, the device performance was evaluated in terms of the energy level alignments at the interfaces, such as the hole injection barriers (phi(h)(iTO/polymer) and phi(h)(polymer/Alq3)) from ITO through the polymers into the Alq3 layer, and the electron injection barrier (phi(e)(polymer/Alq3) or electron/exciton blocking barrier) at the polymer/Alq3 interface.

  1. Polymers for electronics and spintronics.

    PubMed

    Bujak, Piotr; Kulszewicz-Bajer, Irena; Zagorska, Malgorzata; Maurel, Vincent; Wielgus, Ireneusz; Pron, Adam

    2013-12-07

    This critical review is devoted to semiconducting and high spin polymers which are of great scientific interest in view of further development of the organic electronics and the emerging organic spintronic fields. Diversified synthetic strategies are discussed in detail leading to high molecular mass compounds showing appropriate redox (ionization potential (IP), electron affinity (EA)), electronic (charge carrier mobility, conductivity), optoelectronic (electroluminescence, photoconductivity) and magnetic (magnetization, ferromagnetic spin interactions) properties and used as active components of devices such as n- and p-channel field effect transistors, ambipolar light emitting transistors, light emitting diodes, photovoltaic cells, photodiodes, magnetic photoswitches, etc. Solution processing procedures developed with the goal of depositing highly ordered and oriented films of these polymers are also described. This is completed by the description of principal methods that are used for characterizing these macromolecular compounds both in solution and in the solid state. These involve various spectroscopic methods (UV-vis-NIR, UPS, pulse EPR), electrochemistry and spectroelectrochemistry, magnetic measurements (SQUID), and structural and morphological investigations (X-ray diffraction, STM, AFM). Finally, four classes of polymers are discussed in detail with special emphasis on the results obtained in the past three years: (i) high IP, (ii) high |EA|, (iii) low band gap and (iv) high spin ones.

  2. Equation of motion coupled cluster methods for electron attachment and ionization potential in fullerenes C60 and C70

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

    Bhaskaran-Nair, Kiran; Kowalski, Karol; Moreno, Juana

    Discovery of fullerenes has opened a entirely new chapter in chemistry due to their wide range of properties which holds exciting applications in numerous disciplines of science. The Nobel Prize in Chemistry 1996 was awarded jointly to Robert F. Curl Jr., Sir Harold W. Kroto and Richard E. Smalley in recoginition for their discovery of this new carbon allotrope. In this letter we are reporting ionization potential and electron attachment studies on fullerenes (C60 and C70) obtained with novel parallel implementation of the EA-EOM-CCSD and IP-EOM-CCSD methods in NWChem program package.

  3. Dependence of Na+ pump current on external monovalent cations and membrane potential in rabbit cardiac Purkinje cells.

    PubMed Central

    Bielen, F V; Glitsch, H G; Verdonck, F

    1991-01-01

    1. The effect of membrane potential and various extracellular monovalent cations on the Na+ pump current (Ip) was studied on isolated, single Purkinje cells of the rabbit heart by means of whole-cell recording. 2. Ip was identified as current activated by external K+ or its congeners NH4+ and Tl+. The current was blocked by dihydroouabain (1-5 x 10(-4) M) over the whole range of membrane potentials tested. 3. In Na(+)-containing solution half-maximum Ip activation (K0.5) occurred at 0.4 mM-Tl+, 1.9 mM-K+ and 5.7 mM-NH4+ (holding potential, -20 mV). 4. The pump current (Ip)-voltage (V) relationship of the cells in Na(+)-containing media with K+ or its congeners at the tested concentrations greater than K0.5 displayed a steep positive slope at negative membrane potentials between -120 and -20 mV. Little voltage dependence of Ip was observed at more positive potentials up to +40 mV. At even more positive potentials Ip measured at 2 and 5.4 mM-K+ decreased. 5. Lowering the concentration of K+ or its congeners below the K0.5 value in Na(+)-containing solution induced a region of negative slope of the Ip-V curve at membrane potentials positive to -20 mV. 6. The shape of the Ip-V relationship remained unchanged when the K+ concentration (5.4 mM) of the Na(+)-containing medium was replaced by NH4+ or Tl+ concentrations of similar potency to activate Ip (20 mM-NH4+ or 2 mM-Tl+). 7. In Na(+)-free, choline-containing solution half-maximum Ip activation occurred at 0.13 mM-K+ (holding potential, -20 mV). 8. At negative membrane potentials the positive slope of the Ip-V curve was flatter in Na(+)-free than in Na(+)-containing media. A reduced voltage dependence of Ip persisted, regardless of whether choline ions or Li+ were used as a Na+ substitute. 9. Lowering the K+ concentration of the Na(+)-free, choline-containing solution to 0.05 mM evoked an extended region of negative slope in the Ip-V relationship at membrane potentials between -40 and +60 mV. 10. It is concluded that the apparent affinity of the Na(+)-K+ pump towards K+ in cardiac Purkinje cells depends on both the membrane potential and the extracellular Na+ concentration. 11. The region of negative slope of the Ip-V curve observed in cells which were superfused with media containing low concentrations of K+ or its congeners strongly suggests the existence of at least two voltage-sensitive steps in the cardiac Na(+)-K+ pump cycle.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:1665855

  4. Modeling impacts of human footprint and soil variability on the potential distribution of invasive plant species in different biomes

    NASA Astrophysics Data System (ADS)

    Wan, Ji-Zhong; Wang, Chun-Jing; Yu, Fei-Hai

    2017-11-01

    Human footprint and soil variability may be important in shaping the spread of invasive plant species (IPS). However, until now, there is little knowledge on how human footprint and soil variability affect the potential distribution of IPS in different biomes. We used Maxent modeling to project the potential distribution of 29 IPS with wide distributions and long introduction histories in China based on various combinations of climatic correlates, soil characteristics and human footprint. Then, we evaluated the relative importance of each type of environmental variables (climate, soil and human footprint) as well as the difference in range and similarity of the potential distribution of IPS between different biomes. Human footprint and soil variables contributed to the prediction of the potential distribution of IPS, and different types of biomes had varying responses and degrees of impacts from the tested variables. Human footprint and soil variability had the highest tendency to increase the potential distribution of IPS in Montane Grasslands and Shrublands. We propose to integrate the assessment in impacts of human footprint and soil variability on the potential distribution of IPS in different biomes into the prevention and control of plant invasion.

  5. In-plane g factor of low-density two-dimensional holes in a Ge quantum well.

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

    Lu, Tzu-Ming; Harris, Charles Thomas; Huang, Shih-Hsien

    High-mobility two-dimensional (2D) holes residing in a Ge quantum well are a new electronic system with potentials in quantum computing and spintronics. Since for any electronic material, the effective mass and the g factor are two fundamental material parameters that determine the material response to electric and magnetic fields, measuring these two parameters in this material system is thus an important task that needs to be completed urgently. Because of the quantum confinement in the crystal growth direction (z), the biaxial strain of epitaxial Ge on SiGe, and the valance band nature, both the effective mass and the g factormore » can show very strong anisotropy. In particular, the in-plane g factor (g ip) can be vanishingly small while the perpendicular g factor (g z) can be much larger than 2. Here we report the measurement of g ip at very low hole densities using in-plane magneto-resistance measurement performed at the NHMFL.« less

  6. Structure-activity relationships for novel drug precursor N-substituted-6-acylbenzothiazolon derivatives: A theoretical approach

    NASA Astrophysics Data System (ADS)

    Sıdır, Yadigar Gülseven; Sıdır, İsa

    2013-08-01

    In this study, the twelve new modeled N-substituted-6-acylbenzothiazolon derivatives having analgesic analog structure have been investigated by quantum chemical methods using a lot of electronic parameters and structure-activity properties; such as molecular polarizability (α), dipole moment (μ), EHOMO, ELUMO, q-, qH+, molecular volume (Vm), ionization potential (IP), electron affinity (EA), electronegativity (χ), molecular hardness (η), molecular softness (S), electrophilic index (ω), heat of formation (HOF), molar refractivity (MR), octanol-water partition coefficient (log P), thermochemical properties (entropy (S), capacity of heat (Cv)); as to investigate activity relationships with molecular structure. The correlations of log P with Vm, MR, ω, EA, EHOMO - ELUMO (ΔE), HOF in aqueous phase, χ, μ, S, η parameters, respectively are obtained, while the linear relation of log P with IP, Cv, HOF in gas phase are not observed. The log P parameter is obtained to be depending on different properties of compounds due to their complexity.

  7. Size resolved infrared spectroscopy of Na(CH3OH)n (n = 4-7) clusters in the OH stretching region: unravelling the interaction of methanol clusters with a sodium atom and the emergence of the solvated electron.

    PubMed

    Forck, Richard M; Pradzynski, Christoph C; Wolff, Sabine; Ončák, Milan; Slavíček, Petr; Zeuch, Thomas

    2012-03-07

    Size resolved IR action spectra of neutral sodium doped methanol clusters have been measured using IR excitation modulated photoionisation mass spectroscopy. The Na(CH(3)OH)(n) clusters were generated in a supersonic He seeded expansion of methanol by subsequent Na doping in a pick-up cell. A combined analysis of IR action spectra, IP evolutions and harmonic predictions of IR spectra (using density functional theory) of the most stable structures revealed that for n = 4, 5 structures with an exterior Na atom showing high ionisation potentials (IPs) of ~4 eV dominate, while for n = 6, 7 clusters with lower IPs (~3.2 eV) featuring fully solvated Na atoms and solvated electrons emerge and dominate the IR action spectra. For n = 4 simulations of photoionisation spectra using an ab initio MD approach confirm the dominance of exterior structures and explain the previously reported appearance IP of 3.48 eV by small fractions of clusters with partly solvated Na atoms. Only for this cluster size a shift in the isomer composition with cluster temperature has been observed, which may be related to kinetic stabilisation of less Na solvated clusters at low temperatures. Features of slow fragmentation dynamics of cationic Na(+)(CH(3)OH)(6) clusters have been observed for the photoionisation near the adiabatic limit. This finding points to the relevance of previously proposed non-vertical photoionisation dynamics of this system.

  8. Better band gaps with asymptotically corrected local exchange potentials

    NASA Astrophysics Data System (ADS)

    Singh, Prashant; Harbola, Manoj K.; Hemanadhan, M.; Mookerjee, Abhijit; Johnson, D. D.

    2016-02-01

    We formulate a spin-polarized van Leeuwen and Baerends (vLB) correction to the local density approximation (LDA) exchange potential [R. van Leeuwen and E. J. Baerends, Phys. Rev. A 49, 2421 (1994), 10.1103/PhysRevA.49.2421] that enforces the ionization potential (IP) theorem following T. Stein et al. [Phys. Rev. Lett. 105, 266802 (2010), 10.1103/PhysRevLett.105.266802]. For electronic-structure problems, the vLB correction replicates the behavior of exact-exchange potentials, with improved scaling and well-behaved asymptotics, but with the computational cost of semilocal functionals. The vLB + IP correction produces a large improvement in the eigenvalues over those from the LDA due to correct asymptotic behavior and atomic shell structures, as shown in rare-gas, alkaline-earth, zinc-based oxides, alkali halides, sulfides, and nitrides. In half-Heusler alloys, this asymptotically corrected LDA reproduces the spin-polarized properties correctly, including magnetism and half-metallicity. We also consider finite-sized systems [e.g., ringed boron nitride (B12N12 ) and graphene (C24)] to emphasize the wide applicability of the method.

  9. Better band gaps with asymptotically corrected local exchange potentials

    DOE PAGES

    Singh, Prashant; Harbola, Manoj K.; Hemanadhan, M.; ...

    2016-02-22

    In this study, we formulate a spin-polarized van Leeuwen and Baerends (vLB) correction to the local density approximation (LDA) exchange potential [R. van Leeuwen and E. J. Baerends, Phys. Rev. A 49, 2421 (1994)] that enforces the ionization potential (IP) theorem following T. Stein et al. [Phys. Rev. Lett. 105, 266802 (2010)]. For electronic-structure problems, the vLB correction replicates the behavior of exact-exchange potentials, with improved scaling and well-behaved asymptotics, but with the computational cost of semilocal functionals. The vLB + IP correction produces a large improvement in the eigenvalues over those from the LDA due to correct asymptotic behaviormore » and atomic shell structures, as shown in rare-gas, alkaline-earth, zinc-based oxides, alkali halides, sulfides, and nitrides. In half-Heusler alloys, this asymptotically corrected LDA reproduces the spin-polarized properties correctly, including magnetism and half-metallicity. We also consider finite-sized systems [e.g., ringed boron nitride (B 12N 12) and graphene (C 24)] to emphasize the wide applicability of the method.« less

  10. Quantitative molecular orbital energies within a G0W0 approximation

    NASA Astrophysics Data System (ADS)

    Sharifzadeh, S.; Tamblyn, I.; Doak, P.; Darancet, P. T.; Neaton, J. B.

    2012-09-01

    Using many-body perturbation theory within a G 0 W 0 approximation, with a plane wave basis set and using a starting point based on density functional theory within the generalized gradient approximation, we explore routes for computing the ionization potential (IP), electron affinity (EA), and fundamental gap of three gas-phase molecules — benzene, thiophene, and (1,4) diamino-benzene — and compare with experiments. We examine the dependence of the IP and fundamental gap on the number of unoccupied states used to represent the dielectric function and the self energy, as well as the dielectric function plane-wave cutoff. We find that with an effective completion strategy for approximating the unoccupied subspace, and a well converged dielectric function kinetic energy cutoff, the computed IPs and EAs are in excellent quantitative agreement with available experiment (within 0.2 eV), indicating that a one-shot G 0 W 0 approach can be very accurate for calculating addition/removal energies of small organic molecules.

  11. The Electrolyte Genome project: A big data approach in battery materials discovery

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

    Qu, Xiaohui; Jain, Anubhav; Rajput, Nav Nidhi

    2015-06-01

    We present a high-throughput infrastructure for the automated calculation of molecular properties with a focus on battery electrolytes. The infrastructure is largely open-source and handles both practical aspects (input file generation, output file parsing, and information management) as well as more complex problems (structure matching, salt complex generation, and failure recovery). Using this infrastructure, we have computed the ionization potential (IP) and electron affinities (EA) of 4830 molecules relevant to battery electrolytes (encompassing almost 55,000 quantum mechanics calculations) at the B3LYP/6-31+G(*) level. We describe automated workflows for computing redox potential, dissociation constant, and salt-molecule binding complex structure generation. We presentmore » routines for automatic recovery from calculation errors, which brings the failure rate from 9.2% to 0.8% for the QChem DFT code. Automated algorithms to check duplication between two arbitrary molecules and structures are described. We present benchmark data on basis sets and functionals on the G2-97 test set; one finding is that a IP/EA calculation method that combines PBE geometry optimization and B3LYP energy evaluation requires less computational cost and yields nearly identical results as compared to a full B3LYP calculation, and could be suitable for the calculation of large molecules. Our data indicates that among the 8 functionals tested, XYGJ-OS and B3LYP are the two best functionals to predict IP/EA with an RMSE of 0.12 and 0.27 eV, respectively. Application of our automated workflow to a large set of quinoxaline derivative molecules shows that functional group effect and substitution position effect can be separated for IP/EA of quinoxaline derivatives, and the most sensitive position is different for IP and EA. Published by Elsevier B.V« less

  12. Prompt Acceleration of Magnetospheric Electrons to Ultrarelativistic Energies by the 17 March 2015 Interplanetary Shock

    NASA Technical Reports Server (NTRS)

    Kanekal, S. G.; Baker, D. N.; Fennell, J. F.; Jones, A.; Schiller, Q.; Richardson, I.G.; Li, X.; Turner, D. L.; Califf, S.; Claudepierre, S. G.; hide

    2016-01-01

    Trapped electrons in Earth's outer Van Allen radiation belt are influenced profoundly by solar phenomena such as high-speed solar wind streams, coronal mass ejections (CME), and interplanetary (IP) shocks. In particular, strong IP shocks compress the magnetosphere suddenly and result in rapid energization of electrons within minutes. It is believed that the electric fields induced by the rapid change in the geomagnetic field are responsible for the energization. During the latter part of March 2015, a CME impact led to the most powerful geomagnetic storm (minimum Dst = -223 nT at 17 March, 23 UT) observed not only during the Van Allen Probe era but also the entire preceding decade. Magnetospheric response in the outer radiation belt eventually resulted in elevated levels of energized electrons. The CME itself was preceded by a strong IP shock whose immediate effects vis-a-vis electron energization were observed by sensors on board the Van Allen Probes. The comprehensive and high-quality data from the Van Allen Probes enable the determination of the location of the electron injection, timescales, and spectral aspects of the energized electrons. The observations clearly show that ultrarelativistic electrons with energies E greater than 6 MeV were injected deep into the magnetosphere at L approximately equals 3 within about 2 min of the shock impact. However, electrons in the energy range of approximately equals 250 keV to approximately equals 900 keV showed no immediate response to the IP shock. Electric and magnetic fields resulting from the shock-driven compression complete the comprehensive set of observations that provide a full description of the near-instantaneous electron energization.

  13. Heterogeneous IP Ecosystem enabling Reuse (HIER)

    DTIC Science & Technology

    2017-03-22

    Technical Approach and Justification IP reuse is a cornerstone of the commercial electronics market particularly in the digital domain...even in the digital domain. Significant investments in custom ASIC designs have been made by the government, but the IP resulting from such... approach to address requirements for that program. Research Plan The original vision for the HIER activity involved the evaluation

  14. Structural, electronic and vibrational properties of small GaxNy (x+y = 2 5) nanoclusters: a B3LYP-DFT study

    NASA Astrophysics Data System (ADS)

    Yadav, P. S.; Yadav, R. K.; Agrawal, B. K.

    2007-02-01

    An ab initio study of the stability, structural and electronic properties has been made for 49 gallium nitride nanoclusters, GaxNy (x+y = 2-5). Among the various configurations corresponding to a fixed x+y = n value, the configuration possessing the maximum value of binding energy (BE) is named as the most stable structure. The vibrational and optical properties have been investigated only for the most stable structures. A B3LYP-DFT/6-311G(3df) method has been employed to optimize the geometries of the nanoclusters fully. The binding energies (BEs), highest-occupied and lowest-unoccupied molecular orbital (HOMO-LUMO) gaps and the bond lengths have been obtained for all the clusters. We have considered the zero-point energy (ZPE) corrections ignored by the earlier workers. The adiabatic and vertical ionization potentials (IPs) and electron affinities (EAs), charge on atoms, dipole moments, vibrational frequencies, infrared intensities (IR Int.), relative infrared intensities (Rel. IR Int.) and Raman scattering activities have been investigated for the most stable structures. The configurations containing the N atoms in majority are seen to be the most stable structures. The strong N-N bond has an important role in stabilizing the clusters. For clusters containing one Ga atom and all the others as N atoms, the BE increases monotonically with the number of the N atoms. The HOMO-LUMO gap and IP fluctuate with the cluster size n, having larger values for the clusters containing odd number of N atoms. On the other hand, the EA decreases with the cluster size up to n = 3, and shows slow fluctuations thereafter for the larger clusters. In general, the adiabatic IP (EA) is smaller (greater) than the vertical IP (EA) because of the lower energies of the most stable ground state of the cationic (anionic) clusters. The optical absorption spectrum or electron energy loss spectrum (EELS) is unique for every cluster, and may be used to characterize a specific cluster. All the predicted physical quantities are in good agreement with the experimental data wherever available. The growth of these most stable structures should be possible in experiments.

  15. The lowest ionization potentials of Al2

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Barnes, Leslie A.; Taylor, Peter R.

    1988-01-01

    Potential curves for the lowest two electronic states (X 2 sigma g + and A 2 pi u) of Al2(+) were computed using complete active space SCF/multireference CI wave functions and large Gaussian basis sets. The lowest observable vertical ionization potential (to Al2(+) X 2 sigma g +) of the Al2 X 3 pi u ground state is calculated to occur around 6.1 eV, in excellent agreement with the experimental range of 6.0 to 6.42 eV obtained in recent cluster ionization studies by Cox and co-workers. The second vertical ionization potential (to Al2(+) A 2 pi u) occurs near 6.4 eV, also within the experimental range. The adiabatic IP of 5.90 eV is in good agreement with the value of 5.8 to 6.1 eV deduced by Hanley and co-workers from the difference in thresholds between collision induced dissociation processes of Al3(+). The computed IP values are somewhat larger than those deduced from branching ratios in cluster fragmentation experiments by Jarrold and co-workers. The observation of an ionization threshold below 6.42 eV is shown to be incompatible with an Al2 ground electronic state assignment of 3 sigma g -, but the separation between the two lowest states of Al2 is so small that it is likely that both are populated in the experiments, so that this does not provide unambiguous support for the recent theoretical assignment of the ground state as 3 pi u.

  16. Dependence of SOL widths on plasma current and density in NSTX H-mode plasmas

    NASA Astrophysics Data System (ADS)

    Ahn, J.-W.; Maingi, R.; Boedo, J. A.; Soukhanovskii, V.; NSTX Team

    2009-06-01

    The dependence of various SOL widths on the line-averaged density ( n) and plasma current ( Ip) for the quiescent H-mode plasmas with Type-V ELMs in the National Spherical Torus Experiment (NSTX) was investigated. It is found that the heat flux SOL width ( λq), measured by the IR camera, is virtually insensitive to n and has a strong negative dependence on Ip. This insensitivity of λq to n¯e is consistent with the scaling law from JET H-mode plasmas that shows a very weak dependence on the upstream density. The electron temperature, ion saturation current density, electron density, and electron pressure decay lengths ( λTe, λjsat, λne, and λpe, respectively) measured by the probe showed that λTe and λjsat have strong negative dependence on Ip, whereas λne and λpe revealed only a little or no dependence. The dependence of λTe on Ip is consistent with the scaling law in the literature, while λne and λpe dependence shows a different trend.

  17. Stem/progenitor cells from inflamed human dental pulp retain tissue regeneration potential

    PubMed Central

    Alongi, Dominick J; Yamaza, Takayoshi; Song, Yingjie; Fouad, Ashraf F; Romberg, Elaine E; Shi, Songtao; Tuan, Rocky S; Huang, George T-J

    2011-01-01

    Background Potent stem/progenitor cells have been isolated from normal human dental pulps termed dental pulp stem cells (DPSCs). However, it is unknown whether these cells exist in inflamed pulps (IPs). Aims To determine whether DPSCs can be identified and isolated from IPs; and if they can be successfully cultured, whether they retain tissue regeneration potential in vivo. Materials & methods DPSCs from freshly collected normal pulps (NPs) and IPs were characterized in vitro and their tissue regeneration potential tested using an in vivo study model. Results The immunohistochemical analysis showed that IPs expressed higher levels of mesenchymal stem cell markers STRO-1, CD90, CD105 and CD146 compared with NPs (p < 0.05). Flow cytometry analysis showed that DPSCs from both NPs and IPs expressed moderate to high levels of CD146, stage-specific embryonic antigen-4, CD73 and CD166. Total population doubling of DPSCs-IPs (44.6 ± 2.9) was lower than that of DPSCs-NPs (58.9 ± 2.5) (p < 0.05), and DPSCs-IPs appeared to have a decreased osteo/dentinogenic potential compared with DPSCs-NPs based on the mineral deposition in cultures. Nonetheless, DPSCs-IPs formed pulp/dentin complexes similar to DPSCs-NPs when transplanted into immunocompromised mice. Conclusion DPSCs-IPs can be isolated and their mesenchymal stem cell marker profiles are similar to those from NPs. Although some stem cell properties of DPSCs-IPs were altered, cells from some samples remained potent in tissue regeneration in vivo. PMID:20465527

  18. Quantum chemistry study on the open end of single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Hou, Shimin; Shen, Ziyong; Zhao, Xingyu; Xue, Zengquan

    2003-05-01

    Geometrical and electronic structures of open-ended single-walled carbon nanotubes (SWCNTs) are calculated using density functional theory (DFT) with hybrid functional (B3LYP) approximation. Due to different distances between carbon atoms along the edge, reconstruction occurs at the open end of the (4,4) armchair SWCNT, i.e., triple bonds are formed in the carbon atom pairs at the mouth; however, for the (6,0) zigzag SWCNT, electrons in dangling bonds still remain at 'no-bonding' states. The ionization potential (IP) of both (4,4) and (6,0) SWCNTs is increased by their negative intrinsic dipole moments, and localized electronic states existed at both of their open ends.

  19. A comparison of the microstructure and properties of the IPS Empress 2 and the IPS Empress glass-ceramics.

    PubMed

    Höland, W; Schweiger, M; Frank, M; Rheinberger, V

    2000-01-01

    The aim of this report is to analyze the microstructures of glass-ceramics of the IPS Empress 2 and IPS Empress systems by scanning electron microscopy. The main properties of the glass-ceramics were determined and compared to each other. The flexural strength of the pressed glass-ceramic (core material) was improved by a factor of more than three for IPS Empress 2 (lithium disilicate glass-ceramic) in comparison with IPS Empress (leucite glass-ceramic). For the fracture toughness, the K(IC) value was measured as 3.3 +/- 0.3 MPa. m(0.5) for IPS Empress 2 and 1.3 +/- 0.1 MPa. m(0.5) for IPS Empress. Abrasion behavior, chemical durability, and optical properties such as translucency of all glass-ceramics fulfill the dental standards. The authors concluded that IPS Empress 2 can be used to fabricate 3-unit bridges up to the second premolar. Copyright 2000 John Wiley & Sons, Inc.

  20. On the implementation of IP protection using biometrics based information hiding and firewall

    NASA Astrophysics Data System (ADS)

    Basu, Abhishek; Nandy, Kingshuk; Banerjee, Avishek; Giri, Supratick; Sarkar, Souvik; Sarkar, Subir Kumar

    2016-02-01

    System-on-chip-based design style creates a revolution in very large scale integration industry with design efficiency, operating speed and development time. To support this process, reuse and exchange of components are essential in electronic form called intellectual property (IP). This, however, increases the possibility of encroachment of IP of the design. So copyright protection of IP against piracy is the most important concern for IP vendors. The existing solutions for IP protection are still not secure enough with flexibility, cost, etc. This paper proposes an information-hiding-based solution for IP protection by embedding a biometric copyright information and firewall inside an IP in the form of a finite state machine with unique configuration. The scheme first introduces biometric signature-based copyright as ownership proof. Second, firewall interrupts the normal functionality of IP at the end of the user time period. The experimental outcomes of field-programmable-gate-array implementation illustrate the efficiency of the proposed method.

  1. Rates and causes of 30-day readmission and emergency room utilization following head and neck surgery.

    PubMed

    Wu, Vincent; Hall, Stephen F

    2018-05-18

    Unplanned returns to hospital are common, costly, and potentially avoidable. We aimed to investigate and characterize reasons for all-cause readmissions to hospital as in-patients (IPs) and visits to the Emergency Department (ED) within 30-days following patient discharge post head and neck surgery (HNS). Retrospective case series with chart review. All patients within the Department of Otolaryngology - Head and Neck Surgery who underwent HNS for benign and malignant disease from January 1, 2010 to May 31, 2015 were identified. The electronic medical records of readmitted patients were reviewed for reasons of readmission, demographic data, and comorbidities. Following 1281 surgical cases, there were 41 (3.20%) IP readmissions and 109 (8.43%) ED visits within 30-days after discharge for HNS. For IP readmissions, most common causes included infection (26.8%), respiratory symptoms (17.1%), and pain (17.1%). Most common reasons for ED visits were for pain (31.5%), bleeding (17.6%), and infection (14.8%). Readmitted IPs had significantly higher health burden at pre-operative baseline as compared to patients who visited the ED when assessed with the American Society of Anesthesiology scores (p = 0.002) and the Cumulative Illness Rating Scale (p = 0.004). Rate of 30-day IP readmission and ED utilization was 3.20 and 8.43%, respectively. Pain and infection were common causes for returns to hospital. Discharge planning may be improved to target common causes for post-surgical hospital visits in order to decrease readmission rates.

  2. Distribution profile of inositol 1,4,5-trisphosphate receptor isoforms in adrenal chromaffin cells.

    PubMed

    Huh, Yang Hoon; Yoo, Jie Ae; Bahk, Sook Jin; Yoo, Seung Hyun

    2005-05-09

    Given the importance of inositol 1,4,5-trisphosphate receptor (IP(3)R)/Ca(2+) channels in the control of intracellular Ca(2+) concentrations, we determined the relative concentrations of the IP(3)R isoforms in subcellular organelles, based on serially sectioned electron micrographs. The endoplasmic reticulum (ER) was estimated to contain 15-20% of each of the three IP(3)R isoforms while secretory granules contained 58-69%. The nucleus contained approximately 15% each of IP(3)R-1 and -2, but 25% of IP(3)R-3, whereas the plasma membrane contained approximately 1% or less of each. These suggested that secretory granules, the nucleus and ER are at the center of IP(3)-dependent intracellular Ca(2+) control mechanisms in chromaffin cells.

  3. Oxygen-Dependent Photocatalytic Water Reduction with a Ruthenium(imidazolium) Chromophore and a Cobaloxime Catalyst.

    PubMed

    Petermann, Lydia; Staehle, Robert; Pfeifer, Maxim; Reichardt, Christian; Sorsche, Dieter; Wächtler, Maria; Popp, Jürgen; Dietzek, Benjamin; Rau, Sven

    2016-06-06

    Detailed investigations of a photocatalytic system capable of producing hydrogen under pre-catalytic aerobic conditions are reported. This system consists of the NHC precursor chromophore [Ru(tbbpy)2 (RR'ip)][PF6 ]3 (abbreviated as Ru(RR'ip)[PF6 ]3 ; tbbpy=4,4'-di-tert-butyl-2,2'-bipyridine, RR'ip=1,3-disubstituted-1H-imidazo[4,5-f][1,10]phenanthrolinium), the reduction catalyst Co(dmgH)2 (dmgH=dimethylglyoximato), and the electron donor ascorbic acid (AA). Screening studies with respect to solvent, cobaloxime catalyst, electron donor, pH, and concentrations of the individual components yielded optimized photocatalytic conditions. The system shows high activity based on Ru, with turnover numbers up to 2000 under oxygen-free and pre-catalytic aerobic conditions. The turnover frequency in the latter case was even higher than that for the oxygen-free catalyst system. The Ru complexes show high photostability and their first excited state is primarily located on the RR'ip ligand. X-ray crystallographic analysis of the rigid cyclophane-type ligand dd(ip)2 (Br)2 (dd(ip)2 =1,1',3,3'-bis(2,3,5,6-tetramethyl-1,4-phenylene)bis(methylene)bis(1H-imidazo[4,5-f][1,10]phenanthrolinium)) and the catalytic activity of its Ru complex [{(tbbpy)2 Ru}2 (μ-dd(ip)2 )][PF6 ]6 (abbreviated as Ru2 (dd(ip)2 )[PF6 ]6 ) suggest an intermolecular catalytic cycle. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. The potential of technology for enhancing individual placement and support supported employment.

    PubMed

    Lord, Sarah E; McGurk, Susan R; Nicholson, Joanne; Carpenter-Song, Elizabeth A; Tauscher, Justin S; Becker, Deborah R; Swanson, Sarah J; Drake, Robert E; Bond, Gary R

    2014-06-01

    The potential of technology to enhance delivery and outcomes of Individual Placement and Support (IPS) supported employment. IPS supported employment has demonstrated robust success for improving rates of competitive employment among individuals with psychiatric disabilities. Still, a majority of those with serious mental illnesses are not employed (Bond, Drake, & Becker, 2012). The need to promote awareness of IPS and expand services is urgent. In this study, we describe ways that technologies may enhance delivery of IPS supported employment across the care continuum and stakeholder groups. Directions for research are highlighted. published literature, clinical observations, IPS learning collaborative. Technology has the potential to enhance direct service as well as workflow in the IPS supported employment process, which may lead to improved fidelity and client outcomes. Mobile and cloud technologies open opportunities for collaboration, self-directed care, and ongoing support to help clients obtain and maintain meaningful employment. Research is needed to evaluate efficacy of technology-based approaches for promoting client employment outcomes, to identify provider and organization barriers to using technology for IPS delivery, and to determine effective strategies for implementing technology with IPS in different settings and with diverse client audiences.

  5. The Potential of Technology for Enhancing Individual Placement and Support Supported Employment

    PubMed Central

    Lord, Sarah E.; McGurk, Susan R.; Nicholson, Joanne; Carpenter-Song, Elizabeth A.; Tauscher, Justin S.; Becker, Deborah R.; Swanson, Sarah J.; Drake, Robert E.; Bond, Gary R.

    2015-01-01

    Topic The potential of technology to enhance delivery and outcomes of Individual Placement and Support (IPS) supported employment. Purpose IPS supported employment has demonstrated robust success for improving rates of competitive employment among individuals with psychiatric disabilities. Still, a majority of those with serious mental illnesses are not employed (Bond, Drake, & Becker, 2012). The need to promote awareness of IPS and expand services is urgent. In this study, we describe ways that technologies may enhance delivery of IPS supported employment across the care continuum and stakeholder groups. Directions for research are highlighted. Sources Used published literature, clinical observations, IPS learning collaborative. Conclusions and Implications for Practice Technology has the potential to enhance direct service as well as workflow in the IPS supported employment process, which may lead to improved fidelity and client outcomes. Mobile and cloud technologies open opportunities for collaboration, self-directed care, and ongoing support to help clients obtain and maintain meaningful employment. Research is needed to evaluate efficacy of technology-based approaches for promoting client employment outcomes, to identify provider and organization barriers to using technology for IPS delivery, and to determine effective strategies for implementing technology with IPS in different settings and with diverse client audiences. PMID:24912058

  6. Concentration- and time-dependent genotoxicity profiles of isoprene monoepoxides and diepoxide, and the cross-linking potential of isoprene diepoxide in cells.

    PubMed

    Li, Yan; Pelah, Avishay; An, Jing; Yu, Ying-Xin; Zhang, Xin-Yu

    2014-01-01

    Isoprene, a possible carcinogen, is a petrochemical and a natural product being primarily produced by plants. It is biotransformed to 2-ethenyl-2-methyloxirane (IP-1,2-O) and 2-(1-methylethenyl)oxirane (IP-3,4-O), both of which can be further metabolized to 2-methyl-2,2'-bioxirane (MBO). MBO is mutagenic, but IP-1,2-O and IP-3,4-O are not. While IP-1,2-O has been reported being genotoxic, the genotoxicity of IP-3,4-O and MBO, and the cross-linking potential of MBO have not been examined. In the present study, we used the comet assay to investigate the concentration- and time-dependent genotoxicity profiles of the three metabolites and the cross-linking potential of MBO in human hepatocyte L02 cells. For the incubation time of 1 h, all metabolites showed positive concentration-dependent profiles with a potency rank order of IP-3,4-O > MBO > IP-1,2-O. In human hepatocellular carcinoma (HepG2) and human leukemia (HL60) cells, IP-3,4-O was still more potent in inducing DNA breaks than MBO at high concentrations (>200 μM), although at low concentrations (≤200 μM) IP-3,4-O exhibited slightly lower or similar potency to MBO. Interestingly, their time-dependent genotoxicity profiles (0.5-4 h) in L02 cells were different from each other: IP-1,2-O and MBO (200 μM) exhibited negative and positive profiles, respectively, with IP-3,4-O lying in between, namely, IP-3,4-O-caused DNA breaks did not change over the exposure time. Further experiments demonstrated that hydrolysis of IP-1,2-O contributed to the negative profile and MBO induced cross-links at high concentrations and long incubation times. Collectively, the results suggested that IP-3,4-O might play a significant role in the toxicity of isoprene.

  7. Distribution Profile of Inositol 1,4,5-Trisphosphate Receptor/Ca2+ Channels in α and β Cells of Pancreas: Dominant Localization in Secretory Granules and Common Error in Identification of Secretory Granule Membranes.

    PubMed

    Hur, Yong Suk; Yoo, Seung Hyun

    2015-01-01

    The α and β cells of pancreatic islet release important hormones in response to intracellular Ca increases that result from Ca releases through the inositol 1,4,5-trisphoshate receptor (IP3R)/Ca channels. Yet no systematic studies on distribution of IP3R/Ca channels have been done, prompting us to investigate the distribution of all 3 IP3R isoforms. Immunogold electron microscopy was performed to determine the presence and the relative concentrations of all 3 IP3R isoforms in 2 major organelles secretory granules (SGs) and the endoplasmic reticulum of α and β cells of rat pancreas. All 3 IP3R isoforms were present in SG membranes of both cells, and the IP3R concentrations in SGs were ∼2-fold higher than those in the endoplasmic reticulum. Moreover, large halos shown in the electron microscope images of insulin-containing SGs of β cells were gap spaces that resulted from separation of granule membranes from the surrounding cytoplasm. These results strongly suggest the important roles of SGs in IP3-induced, Ca-dependent regulatory secretory pathway in pancreas. Moreover, the accurate location of SG membranes of β cells was further confirmed by the location of another integral membrane protein synaptotagmin V and of membrane phospholipid PI(4,5)P2.

  8. Evaluation of antioxidant activity and electronic structure of aspirin and paracetamol

    NASA Astrophysics Data System (ADS)

    Motozaki, W.; Nagatani, Y.; Kimura, Y.; Endo, K.; Takemura, T.; Kurmaev, E. Z.; Moewes, A.

    2011-01-01

    We present a study of electronic structure, chemical bonding, and antioxidant activity of phenolic antioxidants (aspirin and paracetamol). X-ray photoelectron and emission spectra of the antioxidants have been simulated by deMon density functional theory (DFT) calculations of the molecules. The chemical bonding of aspirin is characterized by the formation of oxygen 'lone-pair' π-orbitals which can neutralize free radicals and thus be related to antioxidant properties of the drug. In the case of paracetamol the additional nitrogen 'lone pair' is formed which can explain toxicity of the drug. We propose an evaluation method of antioxidant activity based on the relationship between experimental half-wave oxidation potential ( Ep/2 ) and calculated ionization potentials ( IP) by the DFT calculations, and can conclude that paracetamol has the higher antioxidant activity than aspirin.

  9. Forward Tracking with the JLab/MEIC Detector Concept

    NASA Astrophysics Data System (ADS)

    Hyde, Charles; JLab/MEIC Design Team

    2015-10-01

    At a future electron ion collider (EIC), the quark-gluon structure of the NN force can be probed in e . g . deeply virtual exclusive scattering on a tensor polarized Deuteron and diffractive DIS on the deuteron with tagging of the NN final state. The MEIC design includes two Interaction Points (IPs), each of which can operate simultaneously at full luminosity. The detector and beam-line optics for IP1 are designed to be nearly hermetic for all particles outside the presumed 10-sigma admittance (longitudinal and transverse) of the figure-8 accelerator lattice. The integration of the IP1 detector with the lattice extends 40 m downstream of the IP in both the electron and ion directions. The central region of the detector is a new 4 m long 3 m diameter 3 Tesla solenoid. Analysis in the forward ion direction is enhanced by the 50 mrad crossing angle at the IP, and a two-stage spectrometer integrated into the first 36 m of the accelerator lattice. In this talk I will present the optics and resolution of the forward ion spectrometer, including resolution effects of an initial beam pipe design. Supported by U.S. Department of Energy.

  10. Developing an Interface to Order and Document Health Education Videos in the Electronic Health Record.

    PubMed

    Wojcik, Lauren

    2015-01-01

    Transitioning to electronic health records (EHRs) provides an opportunity for health care systems to integrate educational content available on interactive patient systems (IPS) with the medical documentation system. This column discusses how one hospital simplified providers' workflow by making it easier to order educational videos and ensure that completed education is documented within the medical record. Integrating the EHR and IPS streamlined the provision of patient education, improved documentation, and supported the organization in meeting core requirements for Meaningful Use.

  11. Calculation of photoelectron spectra of molybdenum and tungsten complexes using Green's functions methods.

    PubMed

    Bayse, Craig A; Ortwine, Kristine N

    2007-08-16

    Green's functions calculations are presented for several complexes of molybdenum and tungsten, two metals that are similar structurally but display subtle, but significant, differences in electronic structure. Outer valence Green's functions IPs for M(CO)6, M(Me)6, MH6, [MCl4O](-), and [MO4](-) (M = Mo, W) are generally within +/-0.2 eV of available experimental photoelectron spectra. The calculations show that electrons in M-L bonding orbitals are ejected at lower energies for Mo while the detachment energy for electrons in d orbitals varies with metal and complex. For the metal carbonyls, the quasiparticle picture assumed in OVGF breaks down for the inner valence pi CO molecular orbitals due to the coupling of two-hole-one-particle charge transfer states to the one-hole states. Incorporation of the 2h1p states through a Tamm-Dancoff approximation calculation accurately represents the band due to detachment from these molecular orbitals. Though the ordering of IPs for Green's functions methods and DFT Koopmans' theorem IPs is similar for the highest IPs for most compounds considered, the breakdown of the quasiparticle picture for the metal carbonyls suggests that scaling of the latter values may result in a fortuitous or incorrect assignment of experimental VDEs.

  12. Spectra of High-Ionization Seyfert 1 Galaxies: Implications for the Narrow-Line Region

    NASA Technical Reports Server (NTRS)

    Moore, David; Cohen, Ross D.; Marcy, Geoffrey W.

    1996-01-01

    We present line profiles and profile parameters for the Narrow-Line Regions (NLRs) of six Seyfert 1 galaxies with high-ionization lines: MCG 8-11-11, Mrk 79, Mrk 704, Mrk 841, NGC 4151, and NGC 5548. The sample was chosen primarily with the goal of obtaining high-quality [Fe VII] lambda6087 and, when possible, [Fe X] lambda6374 profiles to determine if these lines are more likely formed in a physically distinct 'coronal line region' or are formed throughout the NLR along with lines of lower critical density (n(sub cr)) and/or Ionization Potential (IP). We discuss correlations of velocity shift and width with n(sub cr) and IP. In some objects, lines of high IP and/or n(sub cr) are systematically broader than those of low IP/n(sub cr). Of particular interest, however, are objects that show no correlations of line width with either IP or n(sub cr). In these objects, lines of high and low IP/n(sub cr), are remarkably similar, which is difficult to reconcile with the classical picture of the NLR, in which lines of high and low IP/n(sub cr) are formed in physically distinct regions. We argue for similar spatial extents for the flux in lines with similar profiles. Here, as well as in a modeling-oriented companion paper, we develop further an idea suggested by Moore & Cohen that objects that do and do not show line width correlations with IP/n(sub cr) can both be explained in terms of a single NLR model with only a small difference in the cloud column density distinguishing the two types of object. Overall, our objects do not show correlations between the Full Width at Half-Maximum (FWHM) and IP and/or n(sub cr). The width must be defined by a parameter that is sensitive to extended profile wings in order for the correlations to result. We present models in which FWHM correlations with IP and/or n(sub cr) result only after simulating the lower spectral resolution used in previous observational studies. The models that simulate the higher spectral resolution of our observational study produce line width correlations only if the width is defined by a parameter that is more sensitive to extended profile wings than is the FWHM. Our sample of six objects is in effect augmented by incorporating the larger sample (16 objects) of Veilleux into some of our discussion. This paper focuses on new interpretations of NLR emission-line spectra and line profiles that stem directly from the observations. Paper 2 focuses on modeling and complements this paper by illustrating explicitly the effects that spatial variations in electron density, ionization parameter, and column density have on model profiles. By comparing model profiles with the observed profiles presented here, as well as with those presented by Veilleux, Paper 2 yields insight into how the electron density, ionization parameter, and column density likely vary throughout the NLR.

  13. Advances in simulation of wave interactions with extended MHD phenomena

    NASA Astrophysics Data System (ADS)

    Batchelor, D.; Abla, G.; D'Azevedo, E.; Bateman, G.; Bernholdt, D. E.; Berry, L.; Bonoli, P.; Bramley, R.; Breslau, J.; Chance, M.; Chen, J.; Choi, M.; Elwasif, W.; Foley, S.; Fu, G.; Harvey, R.; Jaeger, E.; Jardin, S.; Jenkins, T.; Keyes, D.; Klasky, S.; Kruger, S.; Ku, L.; Lynch, V.; McCune, D.; Ramos, J.; Schissel, D.; Schnack, D.; Wright, J.

    2009-07-01

    The Integrated Plasma Simulator (IPS) provides a framework within which some of the most advanced, massively-parallel fusion modeling codes can be interoperated to provide a detailed picture of the multi-physics processes involved in fusion experiments. The presentation will cover four topics: 1) recent improvements to the IPS, 2) application of the IPS for very high resolution simulations of ITER scenarios, 3) studies of resistive and ideal MHD stability in tokamk discharges using IPS facilities, and 4) the application of RF power in the electron cyclotron range of frequencies to control slowly growing MHD modes in tokamaks and initial evaluations of optimized location for RF power deposition.

  14. Transverse profile of the electron beam for the RHIC electron lenses

    DOE PAGES

    Gu, X.; Altinbas, Z.; Costanzo, M.; ...

    2015-07-10

    To compensate for the beam-beam effects from the proton-proton interactions at the two interaction points IP6 and IP8 in the Relativistic Heavy Ion Collider (RHIC), we are constructing two electron lenses (e-lenses) that we plan to install in the interaction region IR10. Before installing them, the electron gun, collector, instrumentation were tested and the electron beam properties were qualified on an electron lens test bench. We will present the test results and discuss our measurement of the electron beam current and of the electron gun perveance. We achieved a maximum current of 1 A with 5 kV energy for bothmore » the pulsed- and the DC-beam (which is a long turn-by-turn pulse beam). We measured beam transverse profiles with an Yttrium Aluminum Garnet (YAG) screen and pinhole detector, and compared those to simulated beam profiles. Measurements of the pulsed electron beam stability were obtained by measuring the modulator voltage.« less

  15. Structure, electronic and magnetic properties of Mn{sub n} (n=2-8) clusters: A DFT investigation

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

    Kumar, Vipin; Roy, Debesh R., E-mail: drr@ashd.svnit.ac.in

    2016-05-06

    A detail studyon the stability, electronic and magnetic properties of Mn{sub n} (n=2-8) cluster series is performed under the utilization ofdensity functional theory (DFT). The binding energy (B.E.), HOMO-LUMO energy gap (HLG), chemical hardness (η), ionization potential (I.P.), electron affinity (E.A)and electronegativity (χ) of these clusters are predicted. We have also studied the magnetic moments associated with the stable cluster isomers. The lowest energy structures for each cluster sizes aredetermined with a systematic search imposing all possible initial magnetic configuration on the cluster. All the calculations are carried out using a popular GGA functional PBE as proposed by Pardew, Burkemore » and Ernzerhof and implemented in the VASP program.« less

  16. Efficient Density Functional Approximation for Electronic Properties of Conjugated Systems

    NASA Astrophysics Data System (ADS)

    Caldas, Marília J.; Pinheiro, José Maximiano, Jr.; Blum, Volker; Rinke, Patrick

    2014-03-01

    There is on-going discussion about reliable prediction of electronic properties of conjugated oligomers and polymers, such as ionization potential IP and energy gap. Several exchange-correlation (XC) functionals are being used by the density functional theory community, with different success for different properties. In this work we follow a recent proposal: a fraction α of exact exchange is added to the semi-local PBE XC aiming consistency, for a given property, with the results obtained by many-body perturbation theory within the G0W0 approximation. We focus the IP, taken as the negative of the highest occupied molecular orbital energy. We choose α from a study of the prototype family trans-acetylene, and apply this same α to a set of oligomers for which there is experimental data available (acenes, phenylenes and others). Our results indicate we can have excellent estimates, within 0,2eV mean ave. dev. from the experimental values, better than through complete EN - 1 -EN calculations from the starting PBE functional. We also obtain good estimates for the electrical gap and orbital energies close to the band edge. Work supported by FAPESP, CNPq, and CAPES, Brazil, and DAAD, Germany.

  17. Design of an eMonitor system to transport electronic patient care report (ePCR) information in unstable MobileIP wireless environment.

    PubMed

    Giovanni, Mazza G; Shenvi, Rohit; Battles, Marcie; Orthner, Helmuth F

    2008-11-06

    The eMonitor is a component of the ePatient system; a prototype system used by emergency medical services (EMS) personnel in the field to record and transmits electronic patient care report (ePCR) information interactively. The eMonitor component allows each Mobile Data Terminal (MDT) on an unreliable Cisco MobileIP wireless network to securely send and received XML messages used to update patient information to and from the MDT before, during and after the transport of a patient.

  18. Inorganic SnIP-Type Double Helices in Main-Group Chemistry.

    PubMed

    Baumgartner, Maximilian; Weihrich, Richard; Nilges, Tom

    2017-05-05

    Inspired by the synthesis of the first atomic-scale double-helix semiconductor SnIP, this study deals with the question of whether more atomistic, inorganic double-helix compounds are accessible. With the aid of quantum chemical calculations, we have identified 31 candidates by a homoatomic substitution in MXPn, varying the Group 14 M-element from Si to Pb, the Group 17 X-element from F to I and replacing the pnictide (Pn) phosphorus by arsenic. The double-helical structure of SnIP has been used as the starting model for all candidates and the electronic structure and vibrational spectra were determined within the framework of density functional theory (DFT). Varying the outer MX or the inner Pn helix led to the conclusion that iodide- and bromide-containing MXPn compounds show similar structures to SnIP. Here, the calculations indicate interesting effects for electronic band-gap tuning. For the highly polarized fluorides, a segregation of the helices to more complex MX substructures is predicted. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Human Biomarker Discovery and Predictive Models for Disease Progression for Idiopathic Pneumonia Syndrome Following Allogeneic Stem Cell Transplantation*

    PubMed Central

    Schlatzer, Daniela M.; Dazard, Jean-Eudes; Ewing, Rob M.; Ilchenko, Serguei; Tomcheko, Sara E.; Eid, Saada; Ho, Vincent; Yanik, Greg; Chance, Mark R.; Cooke, Kenneth R.

    2012-01-01

    Allogeneic hematopoietic stem cell transplantation (SCT) is the only curative therapy for many malignant and nonmalignant conditions. Idiopathic pneumonia syndrome (IPS) is a frequently fatal complication that limits successful outcomes. Preclinical models suggest that IPS represents an immune mediated attack on the lung involving elements of both the adaptive and the innate immune system. However, the etiology of IPS in humans is less well understood. To explore the disease pathway and uncover potential biomarkers of disease, we performed two separate label-free, proteomics experiments defining the plasma protein profiles of allogeneic SCT patients with IPS. Samples obtained from SCT recipients without complications served as controls. The initial discovery study, intended to explore the disease pathway in humans, identified a set of 81 IPS-associated proteins. These data revealed similarities between the known IPS pathways in mice and the condition in humans, in particular in the acute phase response. In addition, pattern recognition pathways were judged to be significant as a function of development of IPS, and from this pathway we chose the lipopolysaccaharide-binding protein (LBP) protein as a candidate molecular diagnostic for IPS, and verified its increase as a function of disease using an ELISA assay. In a separately designed study, we identified protein-based classifiers that could predict, at day 0 of SCT, patients who: 1) progress to IPS and 2) respond to cytokine neutralization therapy. Using cross-validation strategies, we built highly predictive classifier models of both disease progression and therapeutic response. In sum, data generated in this report confirm previous clinical and experimental findings, provide new insights into the pathophysiology of IPS, identify potential molecular classifiers of the condition, and uncover a set of markers potentially of interest for patient stratification as a basis for individualized therapy. PMID:22337588

  20. Challenges Regarding IP Core Functional Reliability

    NASA Technical Reports Server (NTRS)

    Berg, Melanie D.; LaBel, Kenneth A.

    2017-01-01

    For many years, intellectual property (IP) cores have been incorporated into field programmable gate array (FPGA) and application specific integrated circuit (ASIC) design flows. However, the usage of large complex IP cores were limited within products that required a high level of reliability. This is no longer the case. IP core insertion has become mainstream including their use in highly reliable products. Due to limited visibility and control, challenges exist when using IP cores and subsequently compromise product reliability. We discuss challenges and suggest potential solutions to critical application IP insertion.

  1. Cell surface expression of channel catfish leukocyte immune-type receptors (IpLITRs) and recruitment of both Src homology 2 domain-containing protein tyrosine phosphatase (SHP)-1 and SHP-2.

    PubMed

    Montgomery, Benjamin C S; Mewes, Jacqueline; Davidson, Chelsea; Burshtyn, Deborah N; Stafford, James L

    2009-04-01

    Channel catfish leukocyte immune-type receptors (IpLITRs) are immunoglobulin superfamily (IgSF) members believed to play a role in the control and coordination of cellular immune responses in teleost. Putative stimulatory and inhibitory IpLITRs are co-expressed by different types of catfish immune cells (e.g. NK cells, T cells, B cells, and macrophages) but their signaling potential has not been determined. Following cationic polymer-mediated transfections into human cell lines we examined the surface expression, tyrosine phosphorylation, and phosphatase recruitment potential of two types of putative inhibitory IpLITRs using 'chimeric' expression constructs and an epitope-tagged 'native' IpLITR. We also cloned and expressed the teleost Src homology 2 domain-containing protein tyrosine phosphatases (SHP)-1 and SHP-2 and examined their expression in adult tissues and developing zebrafish embryos. Co-immunoprecipitation experiments support the inhibitory signaling potential of distinct IpLITR-types that bound both SHP-1 and SHP-2 following the phosphorylation of tyrosine residues within their cytoplasmic tail (CYT) regions. Phosphatase recruitment by IpLITRs represents an important first step in understanding their influence on immune cell effector functions and suggests that certain inhibitory signaling pathways are conserved among vertebrates.

  2. Scalable Electrophysiological Investigation of iPS Cell-Derived Cardiomyocytes Obtained by a Lentiviral Purification Strategy.

    PubMed

    Friedrichs, Stephanie; Malan, Daniela; Voss, Yvonne; Sasse, Philipp

    2015-01-08

    Disease-specific induced pluripotent stem (iPS) cells can be generated from patients and differentiated into functional cardiomyocytes for characterization of the disease and for drug screening. In order to obtain pure cardiomyocytes for automated electrophysiological investigation, we here report a novel non-clonal purification strategy by using lentiviral gene transfer of a puromycin resistance gene under the control of a cardiac-specific promoter. We have applied this method to our previous reported wild-type and long QT syndrome 3 (LQTS 3)-specific mouse iPS cells and obtained a pure cardiomyocyte population. These cells were investigated by action potential analysis with manual and automatic planar patch clamp technologies, as well as by recording extracellular field potentials using a microelectrode array system. Action potentials and field potentials showed the characteristic prolongation at low heart rates in LQTS 3-specific, but not in wild-type iPS cell-derived cardiomyocytes. Hence, LQTS 3-specific cardiomyocytes can be purified from iPS cells with a lentiviral strategy, maintain the hallmarks of the LQTS 3 disease and can be used for automated electrophysiological characterization and drug screening.

  3. Effect of ionic activity products on the structure and composition of mineral self assembled on three-dimensional poly(lactide-co-glycolide) scaffolds

    PubMed Central

    Shin, Kyungsup; Jayasuriya, Ambalangodage C.; Kohn, David H.

    2009-01-01

    A biomimetic approach involving the self-assembly of mineral within the pores of three-dimensional porous polymer scaffolds is a promising strategy to integrate advantages of inorganic and organic phases into a single material for hard tissue engineering. Such a material enhances the ability of progenitor cells to differentiate down an osteoblast lineage in vitro and in vivo, compared with polymer scaffolds. The mechanisms regulating mineral formation in this one-step process, however, are poorly understood, especially the effects of ionic activity products (IP) of the mineralizing solution and incubation time. The aims of this study were to define the structure and composition of mineral formed within the pores of biodegradable polymer scaffolds as a function of IP and time. Three-dimensional poly(lactide-co-glycolide) scaffolds were fabricated by solvent casting/particulate leaching and incubated for 4–16 days in six variants of simulated body fluid whose IPs were varied by adjusting ionic concentrations. Scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy demonstrated the formation of carbonated apatite with sub-micrometer sized crystals that grew into spherical globules extending out of the scaffold pore surfaces. As IP increased, more mineral grew on the scaffold pore surfaces, but the apatite became less crystalline and the Ca/P molar ratio decreased from 1.63 ± 0.005 to 1.51 ± 0.002. Since morphology, composition, and structure of mineral are factors that affect cell function, this study demonstrates that the IP of the mineralizing solution is an important modulator of material properties, potentially leading to enhanced control of cell function. PMID:17584901

  4. A tiny event producing an interplanetary type III burst

    NASA Astrophysics Data System (ADS)

    Alissandrakis, C. E.; Nindos, A.; Patsourakos, S.; Kontogeorgos, A.; Tsitsipis, P.

    2015-10-01

    Aims: We investigate the conditions under which small-scale energy release events in the low corona gave rise to strong interplanetary (IP) type III bursts. Methods: We analyzed observations of three tiny events, detected by the Nançay Radio Heliograph (NRH), two of which produced IP type III bursts. We took advantage of the NRH positioning information and of the high cadence of AIA/SDO data to identify the associated extreme-UV (EUV) emissions. We measured positions and time profiles of the metric and EUV sources. Results: We found that the EUV events that produced IP type III bursts were located near a coronal hole boundary, while the one that did not was located in a closed magnetic field region. In all three cases tiny flaring loops were involved, without any associated mass eruption. In the best observed case, the radio emission at the highest frequency (435 MHz) was displaced by ~55'' with respect to the small flaring loop. The metric type III emission shows a complex structure in space and in time, indicative of multiple electron beams, despite the low intensity of the events. From the combined analysis of dynamic spectra and NRH images, we derived the electron beam velocity as well as the height, ambient plasma temperature, and density at the level of formation of the 160 MHz emission. From the analysis of the differential emission measure derived from the AIA images, we found that the first evidence of energy release was at the footpoints, and this was followed by the development of flaring loops and subsequent cooling. Conclusions: Even small energy release events can accelerate enough electrons to give rise to powerful IP type III bursts. The proximity of the electron acceleration site to open magnetic field lines facilitates the escape of the electrons into the interplanetary space. The offset between the site of energy release and the metric type III location warrants further investigation. The movie is available in electronic form at http://www.aanda.org

  5. Interferon-gamma inducible protein-10 as a potential biomarker in localized scleroderma.

    PubMed

    Magee, Kelsey E; Kelsey, Christina E; Kurzinski, Katherine L; Ho, Jonhan; Mlakar, Logan R; Feghali-Bostwick, Carol A; Torok, Kathryn S

    2013-01-01

    The purpose of this study was to evaluate the presence and levels of interferon-gamma inducible protein-10 (IP-10) in the plasma and skin of pediatric localized scleroderma (LS) patients compared to those of healthy pediatric controls and to determine if IP-10 levels correlate to clinical disease activity measures. The presence of IP-10 in the plasma was analyzed using a Luminex panel in 69 pediatric patients with LS and compared to 71 healthy pediatric controls. Of these patients, five had available skin biopsy specimens with concurrent clinical and serological data during the active disease phase, which were used to analyze the presence and location of IP-10 in the skin by immunohistochemistry (IHC). IP-10 levels were significantly elevated in the plasma of LS patients compared to that of healthy controls and correlated to clinical disease activity measures in LS. Immunohistochemistry staining of IP-10 was present in the dermal infiltrate of LS patients and was similar to that found in psoriasis skin specimens, the positive disease control. Elevation of IP-10 levels in the plasma compared to those of healthy controls and the presence of IP-10 staining in the affected skin of LS patients indicates that IP-10 is a potential biomarker in LS. Furthermore, significant elevation of IP-10 in LS patients with active versus inactive disease and correlations between IP-10 levels and standardized disease outcome measures of activity in LS strongly suggest that IP-10 may be a biomarker for disease activity in LS.

  6. Interferon-gamma inducible protein-10 as a potential biomarker in localized scleroderma

    PubMed Central

    2013-01-01

    Introduction The purpose of this study was to evaluate the presence and levels of interferon-gamma inducible protein-10 (IP-10) in the plasma and skin of pediatric localized scleroderma (LS) patients compared to those of healthy pediatric controls and to determine if IP-10 levels correlate to clinical disease activity measures. Methods The presence of IP-10 in the plasma was analyzed using a Luminex panel in 69 pediatric patients with LS and compared to 71 healthy pediatric controls. Of these patients, five had available skin biopsy specimens with concurrent clinical and serological data during the active disease phase, which were used to analyze the presence and location of IP-10 in the skin by immunohistochemistry (IHC). Results IP-10 levels were significantly elevated in the plasma of LS patients compared to that of healthy controls and correlated to clinical disease activity measures in LS. Immunohistochemistry staining of IP-10 was present in the dermal infiltrate of LS patients and was similar to that found in psoriasis skin specimens, the positive disease control. Conclusions Elevation of IP-10 levels in the plasma compared to those of healthy controls and the presence of IP-10 staining in the affected skin of LS patients indicates that IP-10 is a potential biomarker in LS. Furthermore, significant elevation of IP-10 in LS patients with active versus inactive disease and correlations between IP-10 levels and standardized disease outcome measures of activity in LS strongly suggest that IP-10 may be a biomarker for disease activity in LS. PMID:24499523

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

    Hashimoto, Muneaki, E-mail: muneaki@juntendo.ac.jp; Nara, Takeshi, E-mail: tnara@juntendo.ac.jp; Enomoto, Masahiro, E-mail: menomoto@uhnres.utoronto.ca

    Inositol 1,4,5-trisphosphate receptor (IP{sub 3}R) is a key regulator of intracellular Ca{sup 2+} concentration that release Ca{sup 2+} from Ca{sup 2+} stores in response to various external stimuli. IP{sub 3}R also works as a signal hub which form a platform for interacting with various proteins involved in diverse cell signaling. Previously, we have identified an IP{sub 3}R homolog in the parasitic protist, Trypanosoma cruzi (TcIP{sub 3}R). Parasites expressing reduced or increased levels of TcIP{sub 3}R displayed defects in growth, transformation, and infectivity. In the present study, we established parasitic strains expressing a dominant negative form of TcIP{sub 3}R, named DN-TcIP{submore » 3}R, to further investigate the physiological role(s) of TcIP{sub 3}R. We found that the growth of epimastigotes expressing DN-TcIP{sub 3}R was significantly slower than that of parasites with TcIP{sub 3}R expression levels that were approximately 65% of wild-type levels. The expression of DN-TcIP{sub 3}R in epimastigotes induced metacyclogenesis even in the normal growth medium. Furthermore, these epimastigotes showed the presence of dense mitochondria under a transmission electron microscope. Our findings confirm that TcIP{sub 3}R is crucial for epimastigote growth, as previously reported. They also suggest that a strong inhibition of the IP{sub 3}R-mediated signaling induces metacyclogenesis and that mitochondrial integrity is closely associated with this signaling. - Highlights: • We established T. cruzi strains expressing a dominant negative form of the TcIP{sub 3}R. • DN-TcIP{sub 3}R expression inhibits epimastigote growth and induces metacyclogenesis. • Microscopic analysis indicated TcIP{sub 3}R role in maintaining mitochondrial integrity. • Growth, but not microbial density, was altered by mammalian IP{sub 3}R inhibitor (2-APB).« less

  8. Donor Dependent Variations in Hematopoietic Differentiation among Embryonic and Induced Pluripotent Stem Cell Lines

    PubMed Central

    Féraud, Olivier; Valogne, Yannick; Melkus, Michael W.; Zhang, Yanyan; Oudrhiri, Noufissa; Haddad, Rima; Daury, Aurélie; Rocher, Corinne; Larbi, Aniya; Duquesnoy, Philippe; Divers, Dominique; Gobbo, Emilie; Brunet de la Grange, Philippe; Louache, Fawzia; Bennaceur-Griscelli, Annelise; Mitjavila-Garcia, Maria Teresa

    2016-01-01

    Hematopoiesis generated from human embryonic stem cells (ES) and induced pluripotent stem cells (iPS) are unprecedented resources for cell therapy. We compared hematopoietic differentiation potentials from ES and iPS cell lines originated from various donors and derived them using integrative and non-integrative vectors. Significant differences in differentiation toward hematopoietic lineage were observed among ES and iPS. The ability of engraftment of iPS or ES-derived cells in NOG mice varied among the lines with low levels of chimerism. iPS generated from ES cell-derived mesenchymal stem cells (MSC) reproduce a similar hematopoietic outcome compared to their parental ES cell line. We were not able to identify any specific hematopoietic transcription factors that allow to distinguish between good versus poor hematopoiesis in undifferentiated ES or iPS cell lines. There is a relatively unpredictable variation in hematopoietic differentiation between ES and iPS cell lines that could not be predicted based on phenotype or gene expression of the undifferentiated cells. These results demonstrate the influence of genetic background in variation of hematopoietic potential rather than the reprogramming process. PMID:26938212

  9. Ion chemistry of NOO+

    NASA Astrophysics Data System (ADS)

    Midey, A. J.; Fernandez, A. I.; Viggiano, A. A.; Zhang, P.; Morokuma, K.

    2006-03-01

    The kinetics for the reactions of NOO+ ions with neutral molecules having ionization potentials (IPs) from 9.27to15.58eV was measured in a selected ion flow tube at 298K. The NOO+ ions are produced from the reaction of N3++O2 and have been reacted with the following: NO, C6F6, CS2, CF3I, C3F6, OCS, C2H6, Xe, SO2, O3, N2O, CO2, Kr, CO, D2, and N2. Numerous types of reactions were observed with the various neutral reagents, including production of NO+ (which may involve loss of an O from the ion or addition of O to the neutral reactant, although the two channels could not be distinguished here), charge transfer, isomerization of NOO+ to ONO+, and hydride abstraction. High level theoretical calculations of the structures and energetics of the various isomers, electronic states, and transition states of NOO and NOO+ were performed to better understand the observed reactivity. All neutral species with an IP ⩽11.18eV were observed to react with NOO+ in part by charge transfer. Detailed calculations showed that the recommended adiabatic and vertical IPs of NOO are 10.4 and 11.7eV, respectively, at the MRCISD(Q)/AVQZ level of theory. The observed experimental limit for charge transfer of 11.18eV agreed well with the energetics of the final products obtained from theory if dissociation of the neutral metastable product occurred, i.e., the products were X++[O(P3)+NO(Π2)], where [O(P3)+NO(Π2)] formed via dissociation of metastable NOO. Charge exchange with neutral reagent X would, therefore, be exothermic if IP(X )<[IPad(NOO)-ΔE(O+NO)-NOO]=˜11.1eV, where IPad(NOO) is the adiabatic IP. The potential energy surface for the reaction of NOO+ with C2H6 was also calculated, indicating that two pathways for formation of HNO2+C2H5+ exist.

  10. Ab initio study of structural, electronic, optical, and vibrational properties of Zn x S y ( x + y = 2 to 5) nanoclusters

    NASA Astrophysics Data System (ADS)

    Yadav, P. S.; Pandey, D. K.; Agrawal, S.; Agrawal, B. K.

    2010-03-01

    An ab initio study of the stability, structural, electronic. and optical properties has been performed for 46 zinc sulfide nanoclusters Zn x S y ( x + y = n = 2 to 5). Five out of them are seen to be unstable as their vibrational frequencies are found to be imaginary. A B3LYP-DFT/6-311G(3df) method is employed to optimize the geometries and a TDDFT method is used for the study of the optical properties. The binding energies (BE), HOMO-LUMO gaps and the bond lengths have been obtained for all the clusters. For the ZnS2, ZnS3, and ZnS4 nanoclusters, our stable structures are seen to be different from those obtained earlier by using the effective core potentials. We have also considered the zero point energy (ZPE) corrections ignored by the earlier workers. For a fixed value of n, we designate the most stable structure the one, which has maximum final binding energy per atom. The adiabatic and vertical ionization potentials (IP) and electron affinities (EA), charges on the atoms, dipole moments, optical properties, vibrational frequencies, infrared intensities, relative infrared intensities, and Raman scattering activities have been investigated for the most stable structures. The nanoclusters containing large number of S atoms for each n is found to be most stable. The HOMO-LUMO gap decreases from n = 2-3 and then increases above n = 3. The IP and EA both fluctuate with the cluster size n. The optical absorption is quite weak in visible region but strong in the ultraviolet region in most of the nanoclusters except a few. The optical absorption spectrum or electron energy loss spectrum (EELS) is unique for every nanocluster and may be used to characterize a specific nanocluster. The growth of most stable nanoclusters may be possible in the experiments.

  11. Inclusion of orbital relaxation and correlation through the unitary group adapted open shell coupled cluster theory using non-relativistic and scalar relativistic Hamiltonians to study the core ionization potential of molecules containing light to medium-heavy elements

    NASA Astrophysics Data System (ADS)

    Sen, Sangita; Shee, Avijit; Mukherjee, Debashis

    2018-02-01

    The orbital relaxation attendant on ionization is particularly important for the core electron ionization potential (core IP) of molecules. The Unitary Group Adapted State Universal Coupled Cluster (UGA-SUMRCC) theory, recently formulated and implemented by Sen et al. [J. Chem. Phys. 137, 074104 (2012)], is very effective in capturing orbital relaxation accompanying ionization or excitation of both the core and the valence electrons [S. Sen et al., Mol. Phys. 111, 2625 (2013); A. Shee et al., J. Chem. Theory Comput. 9, 2573 (2013)] while preserving the spin-symmetry of the target states and using the neutral closed-shell spatial orbitals of the ground state. Our Ansatz invokes a normal-ordered exponential representation of spin-free cluster-operators. The orbital relaxation induced by a specific set of cluster operators in our Ansatz is good enough to eliminate the need for different sets of orbitals for the ground and the core-ionized states. We call the single configuration state function (CSF) limit of this theory the Unitary Group Adapted Open-Shell Coupled Cluster (UGA-OSCC) theory. The aim of this paper is to comprehensively explore the efficacy of our Ansatz to describe orbital relaxation, using both theoretical analysis and numerical performance. Whenever warranted, we also make appropriate comparisons with other coupled-cluster theories. A physically motivated truncation of the chains of spin-free T-operators is also made possible by the normal-ordering, and the operational resemblance to single reference coupled-cluster theory allows easy implementation. Our test case is the prediction of the 1s core IP of molecules containing a single light- to medium-heavy nucleus and thus, in addition to demonstrating the orbital relaxation, we have addressed the scalar relativistic effects on the accuracy of the IPs by using a hierarchy of spin-free Hamiltonians in conjunction with our theory. Additionally, the contribution of the spin-free component of the two-electron Gaunt term, not usually taken into consideration, has been estimated at the Self-Consistent Field (ΔSCF) level and is found to become increasingly important and eventually quite prominent for molecules with third period atoms and below. The accuracies of the IPs computed using UGA-OSCC are found to be of the same order as the Coupled Cluster Singles Doubles (ΔCCSD) values while being free from spin contamination. Since the UGA-OSCC uses a common set of orbitals for the ground state and the ion, it obviates the need of two N5 AO to MO transformation in contrast to the ΔCCSD method.

  12. Inclusion of orbital relaxation and correlation through the unitary group adapted open shell coupled cluster theory using non-relativistic and scalar relativistic Hamiltonians to study the core ionization potential of molecules containing light to medium-heavy elements.

    PubMed

    Sen, Sangita; Shee, Avijit; Mukherjee, Debashis

    2018-02-07

    The orbital relaxation attendant on ionization is particularly important for the core electron ionization potential (core IP) of molecules. The Unitary Group Adapted State Universal Coupled Cluster (UGA-SUMRCC) theory, recently formulated and implemented by Sen et al. [J. Chem. Phys. 137, 074104 (2012)], is very effective in capturing orbital relaxation accompanying ionization or excitation of both the core and the valence electrons [S. Sen et al., Mol. Phys. 111, 2625 (2013); A. Shee et al., J. Chem. Theory Comput. 9, 2573 (2013)] while preserving the spin-symmetry of the target states and using the neutral closed-shell spatial orbitals of the ground state. Our Ansatz invokes a normal-ordered exponential representation of spin-free cluster-operators. The orbital relaxation induced by a specific set of cluster operators in our Ansatz is good enough to eliminate the need for different sets of orbitals for the ground and the core-ionized states. We call the single configuration state function (CSF) limit of this theory the Unitary Group Adapted Open-Shell Coupled Cluster (UGA-OSCC) theory. The aim of this paper is to comprehensively explore the efficacy of our Ansatz to describe orbital relaxation, using both theoretical analysis and numerical performance. Whenever warranted, we also make appropriate comparisons with other coupled-cluster theories. A physically motivated truncation of the chains of spin-free T-operators is also made possible by the normal-ordering, and the operational resemblance to single reference coupled-cluster theory allows easy implementation. Our test case is the prediction of the 1s core IP of molecules containing a single light- to medium-heavy nucleus and thus, in addition to demonstrating the orbital relaxation, we have addressed the scalar relativistic effects on the accuracy of the IPs by using a hierarchy of spin-free Hamiltonians in conjunction with our theory. Additionally, the contribution of the spin-free component of the two-electron Gaunt term, not usually taken into consideration, has been estimated at the Self-Consistent Field (ΔSCF) level and is found to become increasingly important and eventually quite prominent for molecules with third period atoms and below. The accuracies of the IPs computed using UGA-OSCC are found to be of the same order as the Coupled Cluster Singles Doubles (ΔCCSD) values while being free from spin contamination. Since the UGA-OSCC uses a common set of orbitals for the ground state and the ion, it obviates the need of two N 5 AO to MO transformation in contrast to the ΔCCSD method.

  13. Impact of VoIP and QoS on Open and Distance Learning

    ERIC Educational Resources Information Center

    Saxena, P. C.; Jasola, Sanjay; Sharma, Ramesh C.

    2006-01-01

    Voice over Internet Protocol (VoIP) is becoming a reality in many organizations. The potential for mobility in voice over wi-fi networks will derive demand for the technology. Wireless VoIP is poised to rival VoIP as an alternative telephony tool. Internet has been used to transport data in the form of packet. In the past, Internet did not support…

  14. Triazolophostins: a library of novel and potent agonists of IP3 receptors† †Electronic supplementary information (ESI) available: Synthetic procedures and spectral data for all new compounds, crystal data for disaccharide 4 and details of the docking study. CCDC 1022279. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5ob00440c Click here for additional data file. Click here for additional data file.

    PubMed Central

    Vibhute, Amol M.; Konieczny, Vera; Taylor, Colin W.

    2015-01-01

    IP3 receptors are channels that mediate the release of Ca2+ from the intracellular stores of cells stimulated by hormones or neurotransmitters. Adenophostin A (AdA) is the most potent agonist of IP3 receptors, with the β-anomeric adenine contributing to the increased potency. The potency of AdA and its stability towards the enzymes that degrade IP3 have aroused interest in AdA analogs for biological studies. The complex structure of AdA poses problems that have necessitated optimization of synthetic conditions for each analog. Such lengthy one-at-a-time syntheses limit access to AdA analogs. We have addressed this problem by synthesizing a library of triazole-based AdA analogs, triazolophostins, by employing click chemistry. An advanced intermediate having all the necessary phosphates and a β-azide at the anomeric position was reacted with various alkynes under Cu(i) catalysis to yield triazoles, which upon deprotection gave triazolophostins. All eleven triazolophostins synthesized are more potent than IP3 and some are equipotent with AdA in functional analyses of IP3 receptors. We show that a triazole ring can replace adenine without compromising the potency of AdA and provide facile routes to novel AdA analogs. PMID:25869535

  15. The therapeutic potential of human adipose-derived mesenchymal stem cells producing CXCL10 in a mouse melanoma lung metastasis model.

    PubMed

    Mirzaei, Hamed; Salehi, Hossein; Oskuee, Reza Kazemi; Mohammadpour, Ali; Mirzaei, Hamid Reza; Sharifi, Mohammad Reza; Salarinia, Reza; Darani, Hossein Yousofi; Mokhtari, Mojgan; Masoudifar, Aria; Sahebkar, Amirhossein; Salehi, Rasoul; Jaafari, Mahmoud Reza

    2018-04-10

    Interferon γ-induced protein 10 kDa (IP-10) is a potent chemoattractant and has been suggested to enhance antitumor activity and mediate tumor regression through multiple mechanisms of action. Multiple lines of evidence have indicated that genetically-modified adult stem cells represent a potential source for cell-based cancer therapy. In the current study, we assessed therapeutic potential of human adipose derived mesenchymal stem cells (hADSC) genetically-modified to express IP-10 for the treatment of lung metastasis in an immunocompetent mouse model of metastatic melanoma. A Piggybac vector encoding IP-10 was employed to transfect hADSC ex vivo. Expression and bioactivity of the transgenic protein from hADSCs expressing IP-10 were confirmed prior to in vivo studies. Our results indicated that hADSCs expressing IP-10 could inhibit the growth of B16F10 melanoma cells and significantly prolonged survival. Immunohistochemistry analysis, TUNEL assay and western blot analysis indicated that hADSCs expressing IP-10 inhibited tumor cell growth, hindered tumor infiltration of Tregs, restricted angiogenesis and significantly prolonged survival. In conclusion, our results demonstrated that targeting metastatic tumor sites by hADSC expressing IP-10 could reduce melanoma tumor growth and lung metastasis. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Common genetic variation drives molecular heterogeneity in human iPSCs.

    PubMed

    Kilpinen, Helena; Goncalves, Angela; Leha, Andreas; Afzal, Vackar; Alasoo, Kaur; Ashford, Sofie; Bala, Sendu; Bensaddek, Dalila; Casale, Francesco Paolo; Culley, Oliver J; Danecek, Petr; Faulconbridge, Adam; Harrison, Peter W; Kathuria, Annie; McCarthy, Davis; McCarthy, Shane A; Meleckyte, Ruta; Memari, Yasin; Moens, Nathalie; Soares, Filipa; Mann, Alice; Streeter, Ian; Agu, Chukwuma A; Alderton, Alex; Nelson, Rachel; Harper, Sarah; Patel, Minal; White, Alistair; Patel, Sharad R; Clarke, Laura; Halai, Reena; Kirton, Christopher M; Kolb-Kokocinski, Anja; Beales, Philip; Birney, Ewan; Danovi, Davide; Lamond, Angus I; Ouwehand, Willem H; Vallier, Ludovic; Watt, Fiona M; Durbin, Richard; Stegle, Oliver; Gaffney, Daniel J

    2017-06-15

    Technology utilizing human induced pluripotent stem cells (iPS cells) has enormous potential to provide improved cellular models of human disease. However, variable genetic and phenotypic characterization of many existing iPS cell lines limits their potential use for research and therapy. Here we describe the systematic generation, genotyping and phenotyping of 711 iPS cell lines derived from 301 healthy individuals by the Human Induced Pluripotent Stem Cells Initiative. Our study outlines the major sources of genetic and phenotypic variation in iPS cells and establishes their suitability as models of complex human traits and cancer. Through genome-wide profiling we find that 5-46% of the variation in different iPS cell phenotypes, including differentiation capacity and cellular morphology, arises from differences between individuals. Additionally, we assess the phenotypic consequences of genomic copy-number alterations that are repeatedly observed in iPS cells. In addition, we present a comprehensive map of common regulatory variants affecting the transcriptome of human pluripotent cells.

  17. Inositol hexakisphosphate (IP6) generated by IP5K mediates cullin-COP9 signalosome interactions and CRL function.

    PubMed

    Scherer, Paul C; Ding, Yan; Liu, Zhiqing; Xu, Jing; Mao, Haibin; Barrow, James C; Wei, Ning; Zheng, Ning; Snyder, Solomon H; Rao, Feng

    2016-03-29

    The family of cullin-RING E3 Ligases (CRLs) and the constitutive photomorphogenesis 9 (COP9) signalosome (CSN) form dynamic complexes that mediate ubiquitylation of 20% of the proteome, yet regulation of their assembly/disassembly remains poorly understood. Inositol polyphosphates are highly conserved signaling molecules implicated in diverse cellular processes. We now report that inositol hexakisphosphate (IP6) is a major physiologic determinant of the CRL-CSN interface, which includes a hitherto unidentified electrostatic interaction between the N-terminal acidic tail of CSN subunit 2 (CSN2) and a conserved basic canyon on cullins. IP6, with an EC50 of 20 nM, acts as an intermolecular "glue," increasing cullin-CSN2 binding affinity by 30-fold, thereby promoting assembly of the inactive CRL-CSN complexes. The IP6 synthase, Ins(1,3,4,5,6)P5 2-kinase (IPPK/IP5K) binds to cullins. Depleting IP5K increases the percentage of neddylated, active Cul1 and Cul4A, and decreases levels of the Cul1/4A substrates p27 and p21. Besides dysregulating CRL-mediated cell proliferation and UV-induced apoptosis, IP5K depletion potentiates by 28-fold the cytotoxic effect of the neddylation inhibitor MLN4924. Thus, IP5K and IP6 are evolutionarily conserved components of the CRL-CSN system and are potential targets for cancer therapy in conjunction with MLN4924.

  18. Towards an exact correlated orbital theory for electrons

    NASA Astrophysics Data System (ADS)

    Bartlett, Rodney J.

    2009-12-01

    The formal and computational attraction of effective one-particle theories like Hartree-Fock and density functional theory raise the question of how far such approaches can be taken to offer exact results for selected properties of electrons in atoms, molecules, and solids. Some properties can be exactly described within an effective one-particle theory, like principal ionization potentials and electron affinities. This fact can be used to develop equations for a correlated orbital theory (COT) that guarantees a correct one-particle energy spectrum. They are built upon a coupled-cluster based frequency independent self-energy operator presented here, which distinguishes the approach from Dyson theory. The COT also offers an alternative to Kohn-Sham density functional theory (DFT), whose objective is to represent the electronic density exactly as a single determinant, while paying less attention to the energy spectrum. For any estimate of two-electron terms COT offers a litmus test of its accuracy for principal Ip's and Ea's. This feature for approximating the COT equations is illustrated numerically.

  19. Scalable Electrophysiological Investigation of iPS Cell-Derived Cardiomyocytes Obtained by a Lentiviral Purification Strategy

    PubMed Central

    Friedrichs, Stephanie; Malan, Daniela; Voss, Yvonne; Sasse, Philipp

    2015-01-01

    Disease-specific induced pluripotent stem (iPS) cells can be generated from patients and differentiated into functional cardiomyocytes for characterization of the disease and for drug screening. In order to obtain pure cardiomyocytes for automated electrophysiological investigation, we here report a novel non-clonal purification strategy by using lentiviral gene transfer of a puromycin resistance gene under the control of a cardiac-specific promoter. We have applied this method to our previous reported wild-type and long QT syndrome 3 (LQTS 3)-specific mouse iPS cells and obtained a pure cardiomyocyte population. These cells were investigated by action potential analysis with manual and automatic planar patch clamp technologies, as well as by recording extracellular field potentials using a microelectrode array system. Action potentials and field potentials showed the characteristic prolongation at low heart rates in LQTS 3-specific, but not in wild-type iPS cell-derived cardiomyocytes. Hence, LQTS 3-specific cardiomyocytes can be purified from iPS cells with a lentiviral strategy, maintain the hallmarks of the LQTS 3 disease and can be used for automated electrophysiological characterization and drug screening. PMID:26237021

  20. Performance Analysis of the Mobile IP Protocol (RFC 3344 and Related RFCS)

    DTIC Science & Technology

    2006-12-01

    Encapsulation HMAC Keyed-Hash Message Authentication Code ICMP Internet Control Message Protocol IEEE Institute of Electrical and Electronics Engineers IETF...Internet Engineering Task Force IOS Internetwork Operating System IP Internet Protocol ITU International Telecommunication Union LAN Local Area...network computing. Most organizations today have sophisticated networks that are connected to the Internet. The major benefit reaped from such a

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

    Vermaas, Willem

    The proposed research seeks to address two interconnected, important questions that impact photosynthetic processes and that reflect key differences between the photosynthetic systems of cyanobacteria and plants or algae. The first question is what are the reasons and consequences of the high photosystem I / photosystem II (PS I/PS II) ratio in many cyanobacteria, vs. a ratio that is close to unity in many plants and algae. The corresponding hypothesis is that most of PS I functions in cyclic electron transport, and that reduction in PS I will result primarily in a shortage of ATP rather than reducing power. Thismore » hypothesis will be tested by reducing the amount of PS I by changing the promoter region of the psaAB operon in the cyanobacterium Synechocystis sp. PCC 6803 and generating a range of mutants with different PS I content and thereby different PS I/PS II ratios, with some of the mutants having a PS II/PS I ratio closer to that in plants. The resulting mutants will be probed in terms of their growth rates, electron transfer rates, and P700 redox kinetics. A second question relates to a Mehler-type reaction catalyzed by two flavoproteins, Flv1 and Flv3, that accept electrons from PS I and that potentially function as an electron safety valve leading to no useful purpose of the photosynthesis-generated electrons. The hypothesis to be tested is that Flv1 and Flv3 use the electrons for useful purposes such as cyclic electron flow around PS I. This hypothesis will be tested by analysis of a mutant strain lacking flv3, the gene for one of the flavoproteins. This research is important for a more detailed understanding of the consequences of photosystem stoichiometry and amounts in a living system. Such an understanding is critical for not only insights in the regulatory systems of the organism but also to guide the development of biological or bio-hybrid systems for solar energy conversion into fuels.« less

  2. Experimental and theoretical study of the microsolvation of sodium atoms in methanol clusters: differences and similarities to sodium-water and sodium-ammonia.

    PubMed

    Dauster, Ingo; Suhm, Martin A; Buck, Udo; Zeuch, Thomas

    2008-01-07

    Methanol clusters are generated in a continuous He-seeded supersonic expansion and doped with sodium atoms in a pick-up cell. By this method, clusters of the type Na(CH(3)OH)(n) are formed and subsequently photoionized by applying a tunable dye-laser system. The microsolvation process of the Na 3s electron is studied by determining the ionization potentials (IPs) of these clusters size-selectively for n = 2-40. A decrease is found from n = 2 to 6 and a constant value of 3.19 +/- 0.07 eV for n = 6-40. The experimentally-determined ionization potentials are compared with ionization potentials derived from quantum-chemical calculations, assuming limiting vertical and adiabatic processes. In the first case, energy differences are calculated between the neutral and the ionized cationic clusters of the same geometry. In the second case, the ionized clusters are used in their optimized relaxed geometry. These energy differences and relative stabilities of isomeric clusters vary significantly with the applied quantum-chemical method (B3LYP or MP2). The comparison with the experiment for n = 2-7 reveals strong variations of the ionization potential with the cluster structure indicating that structural diversity and non-vertical pathways give significant signal contributions at the threshold. Based on these findings, a possible explanation for the remarkable difference in IP evolutions of methanol or water and ammonia is presented: for methanol and water a rather localized surface or semi-internal Na 3s electron is excited to either high Rydberg or more localized states below the vertical ionization threshold. This excitation is followed by a local structural relaxation that couples to an autoionization process. For small clusters with n < 6 for methanol and n < 4 for water the addition of solvent molecules leads to larger solvent-metal-ion interaction energies, which consequently lead to lower ionization thresholds. For n = 6 (methanol) and n = 4 (water) this effect comes to a halt, which may be connected with the completion of the first cationic solvation shell limiting the release of local relaxation energy. For Na(NH(3))(n), a largely delocalized and internal electron is excited to autoionizing electronic states, a process that is no longer local and consequently may depend on cluster size up to very large n.

  3. Plasma current start-up using the lower hybrid wave on the TST-2 spherical tokamak

    NASA Astrophysics Data System (ADS)

    Takase, Y.; Ejiri, A.; Inada, T.; Moeller, C. P.; Shinya, T.; Tsujii, N.; Yajima, S.; Furui, H.; Homma, H.; Imamura, K.; Nakamura, K.; Nakamura, K.; Sonehara, M.; Takeuchi, T.; Togashi, H.; Tsuda, S.; Yoshida, Y.

    2015-12-01

    Non-inductive plasma current start-up, ramp-up and sustainment by waves in the lower hybrid wave (LHW) frequency range at 200 MHz were investigated on the TST-2 spherical tokamak (R0 ≤ 0.38 m, a ≤ 0.25 m, Bt0 ≤ 0.3T, Ip ≤ 0.14 MA). Experimental results obtained using three types of antenna were compared. Both the highest plasma current (Ip = 18 kA) and the highest current drive figure of merit ηCD≡n¯eIpR0/PRF=1.4 ×1017 A/W/m2 were achieved using the capacitively-coupled combline (CCC) antenna, designed to excite the LHW with a sharp and highly directional wavenumber spectrum. For Ip greater than about 5 kA, high energy electrons accelerated by the LHW become the dominant carrier of plasma current. The low value of ηCD observed so far are believed to be caused by a rapid loss of energetic electrons and parasitic losses of the LHW energy in the plasma periphery. ηCD is expected to improve by an order of magnitude by increasing the plasma current to improve energetic electron confinement. In addition, edge power losses are expected to be reduced by increasing the toroidal magnetic field to improve wave accessibility to the plasma core, and by launching the LHW from the inboard upper region of the torus to achieve better single-pass absorption.

  4. Fabrication of hydrophobic fluorinated silica-polyamide thin film nanocomposite reverse osmosis membranes with dramatically improved salt rejection.

    PubMed

    Pang, Ruizhi; Zhang, Kaisong

    2018-01-15

    Thin film nanocomposite reverse osmosis (TFN RO) membranes incorporated with hydrophilic nanoparticles show a potential problem that the salt rejection can not be improved significantly. In this study, novel TFN RO membranes incorporated with hydrophobic fluorinated silica nanoparticles were fabricated to improve the salt rejection. Fluorinated silica nanoparticles were well dispersed in organic phase during the interfacial polymerization (IP) process. The TFN RO membranes were characterized with attenuated total reflectance infra-red, field emission scanning electron microscopy, atomic force microscopy and water contact angle measurements. The preparation conditions of TFN RO membranes, including IP reaction time, organic solvent removal time, and fluorinated silica loading, were optimized by characterizing desalination performance using 2000ppm NaCl aqueous solution at 1.55MPa and 25°C. The salt rejection increased significantly from 96.0% without fluorinated silica nanoparticles to 98.6% with the optimal 0.12% (w/v) fluorinated silica nanoparticles, while the water flux decreased slightly from 0.99m 3 /m 2 /day to 0.93m 3 /m 2 /day. This study demonstrated the potential use of hydrophobic nanoparticles in high-performance TFN RO membranes. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Naphthalene bisimides asymmetrically and symmetrically N-substituted with triarylamine--comparison of spectroscopic, electrochemical, electronic and self-assembly properties.

    PubMed

    Rybakiewicz, Renata; Zapala, Joanna; Djurado, David; Nowakowski, Robert; Toman, Petr; Pfleger, Jiri; Verilhac, Jean-Marie; Zagorska, Malgorzata; Pron, Adam

    2013-02-07

    Two semiconducting naphthalene bisimides were comparatively studied: NBI-(TAA)(2), symmetrically N-substituted with triaryl amine and asymmetric NBI-TAA-Oc with triaryl amine and octyl N-substituents. Both compounds show very similar spectroscopic and redox properties but differ in their supramolecular organization. As evidenced by STM, in monolayers on HOPG they form ordered 2D structures, however of different packing patterns. NBI-(TAA)(2) does not form ordered 3D structures, yielding amorphous thin films whereas films of NBI-TAA-Oc are highly crystalline. DFT calculations predict the ionization potential (IP) of 5.22 eV and 5.18 eV for NBI-TAA-Oc and NBI-(TAA)(2), respectively, as well as the electron affinity values (EA) of -3.25 eV and -3.22 eV. These results are consistent with the cyclic voltammetry data which yield similar values of IP (5.20 eV and 5.19 eV) and somehow different values of EA (-3.80 eV and -3.83 eV). As judged from these data, both semiconductors should exhibit ambipolar behavior. Indeed, NBI-TAA-Oc is ambipolar, showing hole and electron mobilities of 4.5 × 10(-5) cm(2)/(V s) and of 2.6 × 10(-4) cm(2)/(V s), respectively, in the field effect transistor configuration. NBI-(TAA)(2) is not ambipolar and yields field effect only in the p-channel configuration. This different behavior is rationalized on the basis of structural factors.

  6. Characterization of organic/organic' and organic/inorganic heterojunctions and their light-absorbing and light-emitting properties

    NASA Astrophysics Data System (ADS)

    Anderson, Michele Lynn

    Increasing the efficiency and durability of organic light-emitting diodes (OLEDs) has attracted attention recently due to their prospective wide-spread use as flat-panel displays. The performance and efficiency of OLEDs is understood to be critically dependent on the quality of the device heterojunctions, and on matching the ionization potentials (IP) and the electron affinities (EA) of the luminescent material (LM) with those of the hole (HTA) and electron (ETA) transport agents, respectively. The color and bandwidth of OLED emission color is thought to reflect the packing of the molecules in the luminescent layer. Finally, materials stability under OLED operating conditions is a significant concern. LM, HTA, and ETA thin films were grown in ultra-high vacuum using the molecular beam epitaxy technique. Thin film structure was determined in situ using reflection high energy electron diffraction (RHEED) and ex situ using UV-Vis spectroscopy. LM, HTA, and ETA occupied frontier orbitals (IP) were characterized by ultraviolet photoelectron spectroscopy (UPS), and their unoccupied frontier orbitals (EA) estimated from UV-Vis and fluorescence spectroscopies in combination with the UPS results. The stability of the molecules toward vacuum deposition was verified by compositional analysis of thin film X-ray photoelectron spectra. The stability of these materials toward redox processes was evaluated by cyclic voltammetry in nonaqueous media. Electrochemical data provide a more accurate estimation of the EA since the energetics for addition of an electron to a neutral molecule can be probed directly. The energetic barriers to charge injection into each layer of the device has been correlated to OLED turn-on voltage, indicating that these measurements may be used to screen potential combinations of materials for OLEDs. The chemical reversibility of LM voltammetry appears to limit the performance and lifetimes of solid-state OLEDs due to degradation of the organic layers. The role of oxygen as an electron trap in OLEDs has also been verified electrochemically. Finally, a more accurate determination of the offset of the occupied energy levels at the interface between two organic layers has been achieved via in situ monitoring of the UPS spectrum during heterojunction formation.

  7. Potential of laryngeal muscle regeneration using induced pluripotent stem cell-derived skeletal muscle cells.

    PubMed

    Dirja, Bayu Tirta; Yoshie, Susumu; Ikeda, Masakazu; Imaizumi, Mitsuyoshi; Nakamura, Ryosuke; Otsuki, Koshi; Nomoto, Yukio; Wada, Ikuo; Hazama, Akihiro; Omori, Koichi

    2016-01-01

    Conclusion Induced pluripotent stem (iPS) cells may be a new potential cell source for laryngeal muscle regeneration in the treatment of vocal fold atrophy after recurrent laryngeal nerve paralysis. Objectives Unilateral vocal fold paralysis can lead to degeneration, atrophy, and loss of force of the thyroarytenoid muscle. At present, there are some treatments such as thyroplasty, arytenoid adduction, and vocal fold injection. However, such treatments cannot restore reduced mass of the thyroarytenoid muscle. iPS cells have been recognized as supplying a potential resource for cell transplantation. The aim of this study was to assess the effectiveness of the use of iPS cells for the regeneration of laryngeal muscle through the evaluation of both in vitro and in vivo experiments. Methods Skeletal muscle cells were generated from tdTomato-labeled iPS cells using embryoid body formation. Differentiation into skeletal muscle cells was analyzed by gene expression and immunocytochemistry. The tdTomato-labeled iPS cell-derived skeletal muscle cells were transplanted into the left atrophied thyroarytenoid muscle. To evaluate the engraftment of these cells after transplantation, immunohistochemistry was performed. Results The tdTomato-labeled iPS cells were successfully differentiated into skeletal muscle cells through an in vitro experiment. These cells survived in the atrophied thyroarytenoid muscle after transplantation.

  8. Determination of the ionization potentials of security-relevant substances with single photon ionization mass spectrometry using synchrotron radiation.

    PubMed

    Schramm, E; Mühlberger, F; Mitschke, S; Reichardt, G; Schulte-Ladbeck, R; Pütz, M; Zimmermann, R

    2008-02-01

    Several ionization potentials (IPs) of security relevant substances were determined with single photon ionization time of flight mass spectrometry (SPI-TOFMS) using monochromatized synchrotron radiation from the "Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung" (BESSY). In detail, the IPs of nine explosives and related compounds, seven narcotics and narcotics precursors, and one chemical warfare agent (CWA) precursor were determined, whereas six IPs already known from the literature were verified correctly. From seven other substances, including one CWA precursor, the IP could not be determined as the molecule ion peak could not be detected. For these substances the appearance energy (AE) of a main fragment was determined. The analyzed security-relevant substances showed IPs significantly below the IPs of common matrix compounds such as nitrogen and oxygen. Therefore, it is possible to find photon energies in between, whereby the molecules of interest can be detected with SPI in very low concentrations due to the shielding of the matrix. All determined IPs except the one of the explosive EGDN were below 10.5 eV. Hence, laser-generated 118 nm photons can be applied for detecting almost all security-relevant substances by, e.g., SPI-TOFMS.

  9. IP-10 measured by Dry Plasma Spots as biomarker for therapy responses in Mycobacterium Tuberculosis infection.

    PubMed

    Tonby, Kristian; Ruhwald, Morten; Kvale, Dag; Dyrhol-Riise, Anne Ma

    2015-03-18

    Tuberculosis (TB) has huge impact on human morbidity and mortality and biomarkers to support rapid TB diagnosis and ensure treatment initiation and cure are needed, especially in regions with high prevalence of multi-drug resistant TB. Soluble interferon gamma inducible protein 10 (IP-10) analyzed from dry plasma spots (DPS) has potential as an immunodiagnostic marker in TB infection. We analyzed IP-10 levels in plasma directly and extracted from DPS in parallel by ELISA from 34 clinically well characterized patients with TB disease before and throughout 24 weeks of effective anti-TB chemotherapy. We detected a significant decline of IP-10 levels in both plasma and DPS already after two weeks of therapy with good correlation between the tests. This was observed both in pulmonary and extrapulmonary TB. In conclusion, plasma IP-10 may serve as an early biomarker for anti-TB chemotherapy responses and the IP-10 DPS method has potential to be developed into a point-of care test for use in resource-limited settings. Further studies must be performed to validate the use of IP-10 DPS in TB high endemic countries.

  10. Upregulation of neurovascular communication through filamin abrogation promotes ectopic periventricular neurogenesis.

    PubMed

    Houlihan, Shauna L; Lanctot, Alison A; Guo, Yan; Feng, Yuanyi

    2016-09-24

    Neuronal fate-restricted intermediate progenitors (IPs) are derived from the multipotent radial glia (RGs) and serve as the direct precursors for cerebral cortical neurons, but factors that control their neurogenic plasticity remain elusive. Here we report that IPs' neuron production is enhanced by abrogating filamin function, leading to the generation of periventricular neurons independent of normal neocortical neurogenesis and neuronal migration. Loss of Flna in neural progenitor cells (NPCs) led RGs to undergo changes resembling epithelial-mesenchymal transition (EMT) along with exuberant angiogenesis that together changed the microenvironment and increased neurogenesis of IPs. We show that by collaborating with β-arrestin, Flna maintains the homeostatic signaling between the vasculature and NPCs, and loss of this function results in escalated Vegfa and Igf2 signaling, which exacerbates both EMT and angiogenesis to further potentiate IPs' neurogenesis. These results suggest that the neurogenic potential of IPs may be boosted in vivo by manipulating Flna-mediated neurovascular communication.

  11. KChIP1 modulation of Kv4.3-mediated A-type K(+) currents and repetitive firing in hippocampal interneurons.

    PubMed

    Bourdeau, M L; Laplante, I; Laurent, C E; Lacaille, J-C

    2011-03-10

    Neuronal A-type K(+) channels regulate action potential waveform, back-propagation and firing frequency. In hippocampal CA1 interneurons located at the stratum lacunosum-moleculare/radiatum junction (LM/RAD), Kv4.3 mediates A-type K(+) currents and a Kv4 β-subunit of the Kv channel interacting protein (KChIP) family, KChIP1, appears specifically expressed in these cells. However, the functional role of this accessory subunit in A-type K(+) currents and interneuron excitability remains largely unknown. Thus, first we studied KChIP1 and Kv4.3 channel interactions in human embryonic kidney 293 (HEK293) cells and determined that KChIP1 coexpression modulated the biophysical properties of Kv4.3 A-type currents (faster recovery from inactivation, leftward shift of activation curve, faster rise time and slower decay) and this modulation was selectively prevented by KChIP1 short interfering RNA (siRNA) knockdown. Next, we evaluated the effects of KChIP1 down-regulation by siRNA on A-type K(+) currents in LM/RAD interneurons in slice cultures. Recovery from inactivation of A-type K(+) currents was slower after KChIP1 down-regulation but other properties were unchanged. In addition, down-regulation of KChIP1 levels did not affect action potential waveform and firing, but increased firing frequency during suprathreshold depolarizations, indicating that KChIP1 regulates interneuron excitability. The effects of KChIP1 down-regulation were cell-specific since CA1 pyramidal cells that do not express KChIP1 were unaffected. Overall, our findings suggest that KChIP1 interacts with Kv4.3 in LM/RAD interneurons, enabling faster recovery from inactivation of A-type currents and thus promoting stronger inhibitory control of firing during sustained activity. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

  12. Elimination of fast inactivation in Kv4 A-type potassium channels by an auxiliary subunit domain.

    PubMed

    Holmqvist, Mats H; Cao, Jie; Hernandez-Pineda, Ricardo; Jacobson, Michael D; Carroll, Karen I; Sung, M Amy; Betty, Maria; Ge, Pei; Gilbride, Kevin J; Brown, Melissa E; Jurman, Mark E; Lawson, Deborah; Silos-Santiago, Inmaculada; Xie, Yu; Covarrubias, Manuel; Rhodes, Kenneth J; Distefano, Peter S; An, W Frank

    2002-01-22

    The Kv4 A-type potassium currents contribute to controlling the frequency of slow repetitive firing and back-propagation of action potentials in neurons and shape the action potential in heart. Kv4 currents exhibit rapid activation and inactivation and are specifically modulated by K-channel interacting proteins (KChIPs). Here we report the discovery and functional characterization of a modular K-channel inactivation suppressor (KIS) domain located in the first 34 aa of an additional KChIP (KChIP4a). Coexpression of KChIP4a with Kv4 alpha-subunits abolishes fast inactivation of the Kv4 currents in various cell types, including cerebellar granule neurons. Kinetic analysis shows that the KIS domain delays Kv4.3 opening, but once the channel is open, it disrupts rapid inactivation and slows Kv4.3 closing. Accordingly, KChIP4a increases the open probability of single Kv4.3 channels. The net effects of KChIP4a and KChIP1-3 on Kv4 gating are quite different. When both KChIP4a and KChIP1 are present, the Kv4.3 current shows mixed inactivation profiles dependent on KChIP4a/KChIP1 ratios. The KIS domain effectively converts the A-type Kv4 current to a slowly inactivating delayed rectifier-type potassium current. This conversion is opposite to that mediated by the Kv1-specific "ball" domain of the Kv beta 1 subunit. Together, these results demonstrate that specific auxiliary subunits with distinct functions actively modulate gating of potassium channels that govern membrane excitability.

  13. Interferon-gamma inducible protein 10 (IP10) induced cisplatin resistance of HCC after liver transplantation through ER stress signaling pathway

    PubMed Central

    Geng, Wei; Lo, Chung-Mau; Ng, Kevin T.P.; Ling, Chang-Chun; Qi, Xiang; Li, Chang-Xian; Zhai, Yuan; Liu, Xiao-Bing; Ma, Yuen-Yuen; Man, Kwan

    2015-01-01

    Tumor recurrence remains an obstacle after liver surgery, especially in living donor liver transplantation (LDLT) for patients with hepatocellular carcinoma (HCC). The acute-phase liver graft injury might potentially induce poor response to chemotherapy in recurrent HCC after liver transplantation. We here intended to explore the mechanism and to identify a therapeutic target to overcome such chemoresistance. The associations among graft injury, overexpression of IP10 and multidrug resistant genes were investigated in a rat liver transplantation model, and further validated in clinical cohort. The role of IP10 on HCC cell proliferation and tumor growth under chemotherapy was studied both in vitro and in vivo. The underlying mechanism was revealed by detecting the activation of endoplasmic reticulum (ER) stress signaling pathways. Moreover, the effect of IP10 neutralizing antibody sensitizing cisplatin treatment was further explored. In rat liver transplantation model, significant up-regulation of IP10 associated with multidrug resistant genes was found in small-for-size liver graft. Clinically, high expression of circulating IP10 was significant correlated with tumor recurrence in HCC patients underwent LDLT. Overexpression of IP10 promoted HCC cell proliferation and tumor growth under cisplatin treatment by activation of ATF6/Grp78 signaling. IP10 neutralizing antibody sensitized cisplatin treatment in nude mice. The overexpression of IP10, which induced by liver graft injury, may lead to cisplatin resistance via ATF6/Grp78 ER stress signaling pathway. IP10 neutralizing antibody could be a potential adjuvant therapy to sensitize cisplatin treatment. PMID:26336986

  14. Phytochemical, spectroscopic and density functional theory study of Diospyrin, and non-bonding interactions of Diospyrin with atmospheric gases

    NASA Astrophysics Data System (ADS)

    Fazl-i-Sattar; Ullah, Zakir; Ata-ur-Rahman; Rauf, Abdur; Tariq, Muhammad; Tahir, Asif Ali; Ayub, Khurshid; Ullah, Habib

    2015-04-01

    Density functional theory (DFT) and phytochemical study of a natural product, Diospyrin (DO) have been carried out. A suitable level of theory was developed, based on correlating the experimental and theoretical data. Hybrid DFT method at B3LYP/6-31G (d,p) level of theory is employed for obtaining the electronic, spectroscopic, inter-molecular interaction and thermodynamic properties of DO. The exact structure of DO is confirmed from the nice validation of the theory and experiment. Non-covalent interactions of DO with different atmospheric gases such as NH3, CO2, CO, and H2O were studied to find out its electroactive nature. The experimental and predicted geometrical parameters, IR and UV-vis spectra (B3LYP/6-31+G (d,p) level of theory) show excellent correlation. Inter-molecular non-bonding interaction of DO with atmospheric gases is investigated through geometrical parameters, electronic properties, charge analysis, and thermodynamic parameters. Electronic properties include, ionization potential (I.P.), electron affinities (E.A.), electrostatic potential (ESP), density of states (DOS), HOMO, LUMO, and band gap. All these characterizations have corroborated each other and confirmed the presence of non-covalent nature in DO with the mentioned gases.

  15. An elevation in physical coupling of type 1 inositol 1,4,5-trisphosphate (IP3) receptors to transient receptor potential 3 (TRPC3) channels constricts mesenteric arteries in genetic hypertension.

    PubMed

    Adebiyi, Adebowale; Thomas-Gatewood, Candice M; Leo, M Dennis; Kidd, Michael W; Neeb, Zachary P; Jaggar, Jonathan H

    2012-11-01

    Hypertension is associated with an elevation in agonist-induced vasoconstriction, but mechanisms involved require further investigation. Many vasoconstrictors bind to phospholipase C-coupled receptors, leading to an elevation in inositol 1,4,5-trisphosphate (IP(3)) that activates sarcoplasmic reticulum IP(3) receptors. In cerebral artery myocytes, IP(3) receptors release sarcoplasmic reticulum Ca(2+) and can physically couple to canonical transient receptor potential 3 (TRPC3) channels in a caveolin-1-containing macromolecular complex, leading to cation current activation that stimulates vasoconstriction. Here, we investigated mechanisms by which IP(3) receptors control vascular contractility in systemic arteries and IP(3)R involvement in elevated agonist-induced vasoconstriction during hypertension. Total and plasma membrane-localized TRPC3 protein was ≈2.7- and 2-fold higher in mesenteric arteries of spontaneously hypertensive rats (SHRs) than in Wistar-Kyoto (WKY) rat controls, respectively. In contrast, IP(3)R1, TRPC1, TRPC6, and caveolin-1 expression was similar. TRPC3 expression was also similar in arteries of pre-SHRs and WKY rats. Control, IP(3)-induced and endothelin-1 (ET-1)-induced fluorescence resonance energy transfer between IP3R1 and TRPC3 was higher in SHR than WKY myocytes. IP3-induced cation current was ≈3-fold larger in SHR myocytes. Pyr3, a selective TRPC3 channel blocker, and calmodulin and IP(3) receptor binding domain peptide, an IP(3)R-TRP physical coupling inhibitor, reduced IP(3)-induced cation current and ET-1-induced vasoconstriction more in SHR than WKY myocytes and arteries. Thapsigargin, a sarcoplasmic reticulum Ca(2+)-ATPase blocker, did not alter ET-1-stimulated vasoconstriction in SHR or WKY arteries. These data indicate that ET-1 stimulates physical coupling of IP(3)R1 to TRPC3 channels in mesenteric artery myocytes, leading to vasoconstriction. Furthermore, an elevation in IP(3)R1 to TRPC3 channel molecular coupling augments ET-1-induced vasoconstriction during hypertension.

  16. The Inner Magnetosphere Plasma Response to Interplanetary Shocks: Van Allen Probes HOPE Observations

    NASA Astrophysics Data System (ADS)

    Winter, L. M.; Denton, M.; Ferradas, C.; Henderson, M. G.; Larsen, B.; Reeves, G.; Skoug, R. M.; Thomsen, M. F.

    2017-12-01

    The Van Allen Probes' Helium, Oxygen, Proton, and Electron (HOPE) sensors measure ion and electron populations in the plasmasphere, plasma sheet, and lower-energy ring current, providing unique observations at low energies (0.001-50 keV) and low L-shell (down to 1.5 RE). We use the capabilities of these two spacecraft to probe changes in the low energy particles in response to interplanetary (IP) shocks. We focus on changes in the plasma energies, composition, and pitch angle distributions following IP shocks and storm sudden commencements from 2012-2017 through a comparison of HOPE observations preceding and post shock.

  17. Three-dimensional resistivity and switching between correlated electronic states in 1T-TaS2

    NASA Astrophysics Data System (ADS)

    Svetin, Damjan; Vaskivskyi, Igor; Brazovskii, Serguei; Mihailovic, Dragan

    2017-04-01

    Recent demonstrations of controlled switching between different ordered macroscopic states by impulsive electromagnetic perturbations in complex materials have opened some fundamental questions on the mechanisms responsible for such remarkable behavior. Here we experimentally address the question of whether two-dimensional (2D) Mott physics can be responsible for unusual switching between states of different electronic order in the layered dichalcogenide 1T-TaS2, or it is a result of subtle inter-layer “orbitronic” re-ordering of its stacking structure. We report on in-plane (IP) and out-of-plane (OP) resistance switching by current-pulse injection at low temperatures. Elucidating the controversial theoretical predictions, we also report on measurements of the anisotropy of the electrical resistivity below room temperature. From the T-dependence of ρ⊥ and ρ||, we surmise that the resistivity is more consistent with collective motion than single particle diffusive or band-like transport. The relaxation dynamics of the metastable state for both IP and OP electron transport are seemingly governed by the same mesoscopic quantum re-ordering process. We conclude that 1T-TaS2 shows resistance switching arising from an interplay of both IP and OP correlations.

  18. Chemical Speciation and Bond Lengths of Organic Solutes by Core-Level Spectroscopy: pH and Solvent Influence on p-Aminobenzoic Acid.

    PubMed

    Stevens, Joanna S; Gainar, Adrian; Suljoti, Edlira; Xiao, Jie; Golnak, Ronny; Aziz, Emad F; Schroeder, Sven L M

    2015-05-04

    Through X-ray absorption and emission spectroscopies, the chemical, electronic and structural properties of organic species in solution can be observed. Near-edge X-ray absorption fine structure (NEXAFS) and resonant inelastic X-ray scattering (RIXS) measurements at the nitrogen K-edge of para-aminobenzoic acid reveal both pH- and solvent-dependent variations in the ionisation potential (IP), 1s→π* resonances and HOMO-LUMO gap. These changes unequivocally identify the chemical species (neutral, cationic or anionic) present in solution. It is shown how this incisive chemical state sensitivity is further enhanced by the possibility of quantitative bond length determination, based on the analysis of chemical shifts in IPs and σ* shape resonances in the NEXAFS spectra. This provides experimental access to detecting even minor variations in the molecular structure of solutes in solution, thereby providing an avenue to examining computational predictions of solute properties and solute-solvent interactions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Chemical Speciation and Bond Lengths of Organic Solutes by Core-Level Spectroscopy: pH and Solvent Influence on p -Aminobenzoic Acid

    DOE PAGES

    Stevens, Joanna S.; Gainar, Adrian; Suljoti, Edlira; ...

    2015-03-18

    Through X-ray absorption and emission spectroscopies, the chemical, electronic and structural properties of organic species in solution can be observed. Near-edge X-ray absorption fine structure (NEXAFS) and resonant inelastic X-ray scattering (RIXS) measurements at the nitrogen K-edge of para-aminobenzoic acid reveal both pH- and solvent-dependent variations in the ionisation potential (IP), 1s→π* resonances and HOMO–LUMO gap. These changes unequivocally identify the chemical species (neutral, cationic or anionic) present in solution. It is shown how this incisive chemical state sensitivity is further enhanced by the possibility of quantitative bond length determination, based on the analysis of chemical shifts in IPs andmore » σ* shape resonances in the NEXAFS spectra. Finally, this provides experimental access to detecting even minor variations in the molecular structure of solutes in solution, thereby providing an avenue to examining computational predictions of solute properties and solute–solvent interactions.« less

  20. Post-fatigue fracture resistance of metal core crowns: press-on metal ceramic versus a conventional veneering system

    PubMed Central

    Agustín-Panadero, Rubén; Campos-Estellés, Carlos; Labaig-Rueda, Carlos

    2015-01-01

    Background The aim of this in vitro study was to compare the mechanical failure behavior and to analyze fracture characteristics of metal ceramic crowns with two veneering systems – press-on metal (PoM) ceramic versus a conventional veneering system – subjected to static compressive loading. Material and Methods Forty-six crowns were constructed and divided into two groups according to porcelain veneer manufacture. Group A: 23 metal copings with porcelain IPS-InLine veneering (conventional metal ceramic). Group B: 23 metal copings with IPS-InLine PoM veneering porcelain. After 120,000 fatigue cycles, the crowns were axially loaded to the moment of fracture with a universal testing machine. The fractured specimens were examined under optical stereomicroscopy and scanning electron microscope. Results Fracture resistance values showed statistically significant differences (Student’s t-test) regarding the type of ceramic veneering technique (p=0.001): Group A (conventional metal ceramics) obtained a mean fracture resistance of 1933.17 N, and Group B 1325.74N (Press-on metal ceramics). The most common type of fracture was adhesive failure (with metal exposure) (p=0.000). Veneer porcelain fractured on the occlusal surface following a radial pattern. Conclusions Metal ceramic crowns made of IPS InLine or IPS InLine PoM ceramics with different laboratory techniques all achieved above-average values for clinical survival in the oral environment according to ISO 6872. Crowns made with IPS InLine by conventional technique resisted fracture an average of 45% more than IPS InLine PoM fabricated with the press-on technique. Key words:Mechanical failure, conventional feldspathic, pressable ceramic, chewing simulator, thermocycling, compressive testing, fracture types, scanning electron microscope. PMID:26155346

  1. Electronic structure of graphene nanoribbons doped with nitrogen atoms: a theoretical insight.

    PubMed

    Torres, A E; Fomine, S

    2015-04-28

    The electronic structure of graphene nanoribbons doped with a graphitic type of nitrogen atoms has been studied using B3LYP, B2PLYP and CAS methods. In all but one case the restricted B3LYP solutions were unstable and the CAS calculations provided evidence for the multiconfigurational nature of the ground state with contributions from two dominant configurations. The relative stability of the doped nanoribbons depends mostly on the mutual position of the dopant atoms and notably less on the position of nitrogen atoms within the nanoribbon. N-graphitic doping affects cationic states much more than anionic ones due the participation of the nitrogen atoms in the stabilization of the positive charge, resulting in a drop in ionization energies (IPs) for N-graphitic doped systems. Nitrogen atoms do not participate in the negative charge stabilization of anionic species and, therefore, the doping does not affect the electron affinities (EAs). The unrestricted B3LYP method is the method of choice for the calculation of IPs and EAs. Restricted B3LYP and B2PLYP produces unreliable results for both IPs and EAs while CAS strongly underestimates the electron affinities. This is also true for the reorganization energies where restricted B3LYP produces qualitatively incorrect results. Doping changes the reorganization energy of the nanoribbons; the hole reorganization energy is generally higher than the corresponding electron reorganization energy due to the participation of nitrogen atoms in the stabilization of the positive charge.

  2. Uncertain translation, uncertain benefit and uncertain risk: ethical challenges facing first-in-human trials of induced pluripotent stem (ips) cells.

    PubMed

    Fung, Ronald K F; Kerridge, Ian H

    2013-02-01

    The discovery of induced pluripotent stem (iPS) cells in 2006 was heralded as a major breakthrough in stem cell research. Since then, progress in iPS cell technology has paved the way towards clinical application, particularly cell replacement therapy, which has refueled debate on the ethics of stem cell research. However, much of the discourse has focused on questions of moral status and potentiality, overlooking the ethical issues which are introduced by the clinical testing of iPS cell replacement therapy. First-in-human trials, in particular, raise a number of ethical concerns including informed consent, subject recruitment and harm minimisation as well as the inherent uncertainty and risks which are involved in testing medical procedures on humans for the first time. These issues, while a feature of any human research, become more complex in the case of iPS cell therapy, given the seriousness of the potential risks, the unreliability of available animal models, the vulnerability of the target patient group, and the high stakes of such an intensely public area of science. Our paper will present a detailed case study of iPS cell replacement therapy for Parkinson's disease to highlight these broader ethical and epistemological concerns. If we accept that iPS cell technology is fraught with challenges which go far beyond merely refuting the potentiality of the stem cell line, we conclude that iPS cell research should not replace, but proceed alongside embryonic and adult somatic stem cell research to promote cross-fertilisation of knowledge and better clinical outcomes. © 2011 Blackwell Publishing Ltd.

  3. DFT/TDDFT investigation on the photophysical properties of a series of phosphorescent cyclometalated complexes based on the benchmark complex FIrpic

    NASA Astrophysics Data System (ADS)

    Han, Deming; Gong, Ping; Lv, Shuhui; Zhao, Lihui; Zhao, Henan

    2018-05-01

    The photophysical properties of four Ir(III) complexes have been investigated by means of the density functional theory/time-dependent density functional theory (DFT/TDDFT). The effect of the electron-withdrawing and electron-donating substituents on charge injection, transport, absorption and phosphorescent properties has been studied. The theoretical calculation shows that the lowest-lying singlet absorptions for complexes 1-4 are located at 387, 385, 418 and 386 nm, respectively. For 1-4, the phosphorescence at 465, 485, 494 and 478 nm is mainly attributed to the LUMO → HOMO and LUMO → HOMO-1 transition configurations characteristics. In addition, ionisation potential (IP), electron affinities (EAs) and reorganisation energy have been investigated to evaluate the charge transfer and balance properties between hole and electron. The balance of the reorganisation energies for complex 3 is better than others. The difference between hole transport and electron transport for complex 3 is the smallest among these complexes, which is beneficial to achieve the hole and electron transfer balance in emitting layer.

  4. Spectroscopy of N,N-dimethylformamide in the VUV and IR regions: Experimental and computational studies

    NASA Astrophysics Data System (ADS)

    Shastri, Aparna; Das, Asim Kumar; Krishnakumar, Sunanda; Singh, Param Jeet; Raja Sekhar, B. N.

    2017-12-01

    The electronic absorption spectrum of N,N-dimethylformamide (DMF) is studied in the 45 000-80 000 cm-1 (5.6-9.9 eV) region using synchrotron radiation. The vacuum ultraviolet (VUV) spectrum comprises mostly of Rydberg series of ns, np, and nd types converging to the first two ionization potentials (IPs). Quantum defect values obtained are consistent with excitation of an electron from the highest occupied molecular orbitals localized on nitrogen (4a″) and oxygen (16a'); in addition, the 3s Rydberg transition converging to the third IP (3a″) is observed at 8.95 eV. A reinvestigation of the infrared spectrum of DMF in the 500-4000 cm-1 region with the help of density functional theory (DFT) calculations establishes the planarity of the ground state and leads to revision of several vibrational assignments. Vertical excited state energies and their valence/Rydberg character are predicted using time dependent DFT calculations; excellent correlation is achieved between theoretical results and experimentally observed spectral features. Potential energy curves of the first few excited states give additional insights into the nature of the excited states and their role in photodissociation dynamics. The absorption spectrum of DMF in the region >63 400 cm-1 (7.85 eV) as well as a complete set of spectral assignments in the VUV region (45 000-80 000 cm-1) is reported for the first time. This work represents a comprehensive study of the absorption spectra of DMF in the VUV and infrared regions.

  5. ISS and STS Commercial Off-the-Shelf Router Testing

    NASA Technical Reports Server (NTRS)

    Ivancie, William D.; Bell, Terry L.; Shell, Dan

    2002-01-01

    This report documents the results of testing performed with commercial off-the-shelf (COTS) routers and Internet Protocols (IPs) to determine if COTS equipment and IP could be utilized to upgrade NASA's current Space Transportation System (STS), the Shuttle, and the International Space Station communication infrastructure. Testing was performed by NASA Glenn Research Center (GRC) personnel within the Electronic Systems Test Laboratory (ESTE) with cooperation from the Mission Operations Directorate (MOD) Qualification and Utilization of Electronic System Technology (QUEST) personnel. The ESTE testing occurred between November 1 and 9, 2000. Additional testing was performed at NASA Glenn Research Center in a laboratory environment with equipment configured to emulate the STS. This report documents those tests and includes detailed test procedures, equipment interface requirements, test configurations and test results. The tests showed that a COTS router and standard Transmission Control Protocols and Internet Protocols (TCP/IP) could be used for both the Shuttle and the Space Station if near-error-free radio links are provided.

  6. Electron energy distribution function in the divertor region of the COMPASS tokamak during neutral beam injection heating

    NASA Astrophysics Data System (ADS)

    Hasan, E.; Dimitrova, M.; Havlicek, J.; Mitošinková, K.; Stöckel, J.; Varju, J.; Popov, Tsv K.; Komm, M.; Dejarnac, R.; Hacek, P.; Panek, R.; the COMPASS Team

    2018-02-01

    This paper presents the results from swept probe measurements in the divertor region of the COMPASS tokamak in D-shaped, L-mode discharges, with toroidal magnetic field BT = 1.15 T, plasma current Ip = 180 kA and line-average electron densities varying from 2 to 8×1019 m-3. Using neutral beam injection heating, the electron energy distribution function is studied before and during the application of the beam. The current-voltage characteristics data are processed using the first-derivative probe technique. This technique allows one to evaluate the plasma potential and the real electron energy distribution function (respectively, the electron temperatures and densities). At the low average electron density of 2×1019 m-3, the electron energy distribution function is bi-Maxwellian with a low-energy electron population with temperatures 4-6 eV and a high-energy electron group 12-25 eV. As the line-average electron density is increased, the electron temperatures decrease. At line-average electron densities above 7×1019 m-3, the electron energy distribution function is found to be Maxwellian with a temperature of 6-8.5 eV. The effect of the neutral beam injection heating power in the divertor region is also studied.

  7. Possible involvement of nitric oxide (NO) signaling pathway in the antidepressant-like effect of MK-801(dizocilpine), a NMDA receptor antagonist in mouse forced swim test.

    PubMed

    Dhir, Ashish; Kulkarni, S K

    2008-03-01

    L-arginine-nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) is an important signaling pathway involved in depression. With this information, the present study aimed to study the involvement of this signaling pathway in the antidepressant-like action of MK-801 (dizocilpine; N-methyl-d-aspartate receptor antagonist) in the mouse forced-swim test. Total immobility period was recorded in mouse forced swim test for 6 min. MK-801 (5-25 microg/kg., ip) produced a U-shaped curve in reducing the immobility period. The antidepressant-like effect of MK-801 (10 microg/kg, ip) was prevented by pretreatment with L-arginine (750 mg/kg, ip) [substrate for nitric oxide synthase (NOS)]. Pretreatment of mice with 7-nitroindazole (7-NI) (25 mg/kg, ip) [a specific neuronal nitric oxide synthase inhibitor] produced potentiation of the action of subeffective dose of MK-801 (5 microg/kg, ip). In addition, treatment of mice with methylene blue (10 mg/kg, ip) [direct inhibitor of both nitric oxide synthase and soluble guanylate cyclase] potentiated the effect of MK-801 (5 microg/kg, ip) in the forced-swim test. Further, the reduction in the immobility period elicited by MK-801 (10 microg/kg, ip) was also inhibited by pretreatment with sildenafil (5 mg/kg, ip) [phosphodiesterase 5 inhibitor]. The various modulators used in the study and their combination did not produce any changes in locomotor activity per se and in combination with MK-801. MK-801 however, at higher doses (25 microg/kg, ip) produced hyperlocomotion. The results demonstrated the involvement of nitric oxide signaling pathway in the antidepressant-like effect of MK-801 in mouse forced-swim test.

  8. Isotopic Randomness and Maxwell's Demon

    NASA Astrophysics Data System (ADS)

    Berezin, Alexander A.

    2005-03-01

    Isotopic disorder in crystals can lead to suppression of thermal conductivity, mobility variations and (weak) Anderson localization on isotopic fluctuations. The latter (AAB, J.ChemPhys.1984) is akin to polaron effect (self-localization due polarization). Possibility of isotopic patterning (IP) increases near melting point (thermally activated isotopic hopping swaps). Crystal near melting threshold become “informationally sensitive” as if its IP is operated by some external Maxwell’s Demon, MD (AAB, URAM J, 2002). At this state short range (e.g. electrostatic inverse square) forces evolve into long-range interactions (due to divergence of order parameter) and information sensitivity can be further amplified by (say) a single fast electron (e.g. beta-particle from decay of 14-C or other radioactive isotope) which may result in cascade of impact ionization events and (short time-scale) enhancement of screening by impact-generated non-equilibrium (non-thermal) electrons. In this state informationally driven (MD-controlled) IP (Eccles effect) can result in decrease of positional entropy signifying emergence of physical complexity out of pure information, similar to peculiar “jinni effect” on closed time loops in relativistic cosmology (R.J.Gott, 2001) or Wheeler’s “it from bit” metaphor. By selecting special IP, MD modifies ergodicity principle in favor of info rich states.

  9. Syntheses, spectroscopic properties and molecular structure of silver phytate complexes - IR, UV-VIS studies and DFT calculations

    NASA Astrophysics Data System (ADS)

    Zając, A.; Dymińska, L.; Lorenc, J.; Ptak, M.; Hanuza, J.

    2018-03-01

    Silver phytate IP6, IP6Ag, IP6Ag2 and IP6Ag3 complexes in the solid state have been synthesized changing the phosphate to metal mole ratio. The obtained products have been characterized by means of chemical and spectroscopic studies. Attenuated total reflection Fourier transform infrared technique and Raman microscope were used in the measurements. These results were discussed in terms of DFT (Density Functional Theory) quantum chemical calculations using the B3LYP/6-31G(d,p) approach. The molecular structures of these compounds have been proposed on the basis of group theory and geometry optimization taking into account the shape and the number of the observed bands corresponding to the stretching and bending vibrations of the phosphate group and metal-oxygen polyhedron. The role of inter- and intra-hydrogen bonds in stabilization of the structure has been discussed. It was found that three types of hydrogen bonds appear in the studied compounds: terminal, and those engaged in the inter- and intra-molecular interactions. The Fermi resonance as a result of the strong intra-molecular Osbnd H⋯O hydrogen bonds was discovered. Electron absorption spectra have been measured to characterize the electron properties of the studied complexes and their local symmetry.

  10. Human induced pluripotent stem cells labeled with fluorescent magnetic nanoparticles for targeted imaging and hyperthermia therapy for gastric cancer.

    PubMed

    Li, Chao; Ruan, Jing; Yang, Meng; Pan, Fei; Gao, Guo; Qu, Su; Shen, You-Lan; Dang, Yong-Jun; Wang, Kan; Jin, Wei-Lin; Cui, Da-Xiang

    2015-09-01

    Human induced pluripotent stem (iPS) cells exhibit great potential for generating functional human cells for medical therapies. In this paper, we report for use of human iPS cells labeled with fluorescent magnetic nanoparticles (FMNPs) for targeted imaging and synergistic therapy of gastric cancer cells in vivo. Human iPS cells were prepared and cultured for 72 h. The culture medium was collected, and then was co-incubated with MGC803 cells. Cell viability was analyzed by the MTT method. FMNP-labeled human iPS cells were prepared and injected into gastric cancer-bearing nude mice. The mouse model was observed using a small-animal imaging system. The nude mice were irradiated under an external alternating magnetic field and evaluated using an infrared thermal mapping instrument. Tumor sizes were measured weekly. iPS cells and the collected culture medium inhibited the growth of MGC803 cells. FMNP-labeled human iPS cells targeted and imaged gastric cancer cells in vivo, as well as inhibited cancer growth in vivo through the external magnetic field. FMNP-labeled human iPS cells exhibit considerable potential in applications such as targeted dual-mode imaging and synergistic therapy for early gastric cancer.

  11. Exploring attitudes of Canadian radiation oncologists, radiation therapists, physicists, and oncology nurses regarding interprofessional teaching and learning.

    PubMed

    Koo, Kaitlin; Di Prospero, Lisa; Barker, Ruth; Sinclair, Lynne; McGuffin, Merrylee; Ng, Alita; Szumacher, Ewa

    2014-06-01

    The purposes of this exploratory study were to investigate the attitudes of radiation oncology professionals regarding interprofessional (IP) teaching and interprofessional education (IPE), to identify the challenges faced by radiation oncologists who teach within an IP context, and to discover new strategies to aid professionals teaching IP students. A questionnaire was developed through the review of existing literature on IPE using Medline. The proposed group of questions was selected by educators from different professions actively involved in IPE. The final revised questionnaire consisted of three main domains assessing the understanding of IP concepts, attitudes toward IP teaching and learning environments, and attitudes toward health-care teams. An open-ended comment section was included. The questionnaire was administered to health-care professionals (physicists, radiation oncologists, and radiation therapists) nationally through SurveyMonkey® (electronic survey). A total of 220 respondents provided demographic information. Half of these respondents indicated that they previously received education relating to IPE. A high level of agreement was received for nearly all the questions. There were no significant statistical differences among the three different professional respondent groups for any question. Overall, most of the respondents demonstrated a good knowledge and understanding of IP concepts and advocated IP training and collaboration.

  12. Comparative calibration of IP scanning equipment

    NASA Astrophysics Data System (ADS)

    Ingenito, F.; Andreoli, P.; Batani, D.; Boutoux, G.; Cipriani, M.; Consoli, F.; Cristofari, G.; Curcio, A.; De Angelis, R.; Di Giorgio, G.; Ducret, J.; Forestier-Colleoni, P.; Hulin, S.; Jakubowska, K.; Rabhi, N.

    2016-05-01

    Imaging Plates (IP) are diagnostic devices which contain a photostimulable phosphor layer that stores the incident radiation dose as a latent image. The image is read with a scanner which stimulates the decay of electrons, previously excited by the incident radiation, by exposition to a laser beam. This results in emitted light, which is detected by photomultiplier tubes; so the latent image is reconstructed. IPs have the interesting feature that can be reused many times, after erasing stored information. Algorithms to convert signals stored in the detector to Photostimulated luminescence (PSL) counts depend on the scanner and are not available on every model. A comparative cross-calibration of the IP scanner Dürr CR35 BIO, used in ABC laboratory, was performed, using the Fujifilm FLA 7000 scanner as a reference, to find the equivalence between grey-scale values given by the Dürr scanner to PSL counts. Using an IP and a 55Fe β-source, we produced pairs of samples with the same exposition times, which were analysed by both scanners, placing particular attention to fading times of the image stored on IPs. Data analysis led us to the determine a conversion formula which can be used to compare data of experiments obtained in different laboratories and to use IP calibrations available, till now, only for Fujifilm scanners.

  13. Sustained signalling by PTH modulates IP3 accumulation and IP3 receptors through cyclic AMP junctions

    PubMed Central

    Meena, Abha; Tovey, Stephen C.; Taylor, Colin W.

    2015-01-01

    ABSTRACT Parathyroid hormone (PTH) stimulates adenylyl cyclase through type 1 PTH receptors (PTH1R) and potentiates the Ca2+ signals evoked by carbachol, which stimulates formation of inositol 1,4,5-trisphosphate (IP3). We confirmed that in HEK cells expressing PTH1R, acute stimulation with PTH(1-34) potentiated carbachol-evoked Ca2+ release. This was mediated by locally delivered cyclic AMP (cAMP), but unaffected by inhibition of protein kinase A (PKA), exchange proteins activated by cAMP, cAMP phosphodiesterases (PDEs) or substantial inhibition of adenylyl cyclase. Sustained stimulation with PTH(1-34) causes internalization of PTH1R–adenylyl cyclase signalling complexes, but the consequences for delivery of cAMP to IP3R within cAMP signalling junctions are unknown. Here, we show that sustained stimulation with PTH(1-34) or with PTH analogues that do not evoke receptor internalization reduced the potentiated Ca2+ signals and attenuated carbachol-evoked increases in cytosolic IP3. Similar results were obtained after sustained stimulation with NKH477 to directly activate adenylyl cyclase, or with the membrane-permeant analogue of cAMP, 8-Br-cAMP. These responses were independent of PKA and unaffected by substantial inhibition of adenylyl cyclase. During prolonged stimulation with PTH(1-34), hyperactive cAMP signalling junctions, within which cAMP is delivered directly and at saturating concentrations to its targets, mediate sensitization of IP3R and a more slowly developing inhibition of IP3 accumulation. PMID:25431134

  14. c-MYC independent nuclear reprogramming favors cardiogenic potential of induced pluripotent stem cells

    PubMed Central

    Martinez-Fernandez, Almudena; Nelson, Timothy J.; Ikeda, Yasuhiro; Terzic, Andre

    2010-01-01

    Induced pluripotent stem cell (iPS) technology has launched a new platform in regenerative medicine aimed at deriving unlimited replacement tissue from autologous sources through somatic cell reprogramming using stemness factor sets. In this way, authentic cardiomyocytes have been obtained from iPS and recently demonstrated in proof-of-principle studies to repair infarcted heart. Optimizing the cardiogenic potential of iPS progeny would ensure a maximized yield of bioengineered cardiac tissue. Here, we reprogrammed fibroblasts in the presence or absence of c-MYC to determine if the acquired cardiogenicity is sensitive to the method of nuclear reprogramming. Using lentiviral constructs that expressed stemness factors SOX2, OCT4, and KLF4 with or without c-MYC, iPS clones generated through fibroblast reprogramming demonstrated indistinguishable characteristics for 5 days of differentiation with similar cell morphology, growth rates, and chimeric embryo integration. However, 4-factor c-MYC dependent nuclear reprogramming produced iPS progeny that consistently prolonged the expression of pluripotent Oct-4 and Fgf4 genes and repressed cardiac differentiation. In contrast, 3-factor c-MYC-less iPS clones efficiently up-regulated pre-cardiac (CXCR4, Flk-1, and Mesp1/2) and cardiac (Nkx2.5, Mef2c, and Myocardin) gene expression patterns. In fact, 3-factor iPS progeny demonstrated early and robust cardiogenesis during in vitro differentiation with consistent beating activity, sarcomere maturation, and rhythmical intracellular calcium dynamics. Thus, nuclear reprogramming independent of c-MYC enhances production of pluripotent stem cells with innate cardiogenic potential. PMID:20221419

  15. Efficient Generation of iPS Cells from Skeletal Muscle Stem Cells

    PubMed Central

    Tan, Kah Yong; Eminli, Sarah; Hettmer, Simone; Hochedlinger, Konrad; Wagers, Amy J.

    2011-01-01

    Reprogramming of somatic cells into inducible pluripotent stem cells generally occurs at low efficiency, although what limits reprogramming of particular cell types is poorly understood. Recent data suggest that the differentiation status of the cell targeted for reprogramming may influence its susceptibility to reprogramming as well as the differentiation potential of the induced pluripotent stem (iPS) cells that are derived from it. To assess directly the influence of lineage commitment on iPS cell derivation and differentiation, we evaluated reprogramming in adult stem cell and mature cell populations residing in skeletal muscle. Our data using clonal assays and a second-generation inducible reprogramming system indicate that stem cells found in mouse muscle, including resident satellite cells and mesenchymal progenitors, reprogram with significantly greater efficiency than their more differentiated daughters (myoblasts and fibroblasts). However, in contrast to previous reports, we find no evidence of biased differentiation potential among iPS cells derived from myogenically committed cells. These data support the notion that adult stem cells reprogram more efficiently than terminally differentiated cells, and argue against the suggestion that “epigenetic memory” significantly influences the differentiation potential of iPS cells derived from distinct somatic cell lineages in skeletal muscle. PMID:22028872

  16. Multiprotein assembly of Kv4.2, KChIP3 and DPP10 produces ternary channel complexes with ISA-like properties.

    PubMed

    Jerng, Henry H; Kunjilwar, Kumud; Pfaffinger, Paul J

    2005-11-01

    Kv4 pore-forming subunits are the principal constituents of the voltage-gated K+ channel underlying somatodendritic subthreshold A-type currents (I(SA)) in neurones. Two structurally distinct types of Kv4 channel modulators, Kv channel-interacting proteins (KChIPs) and dipeptidyl-peptidase-like proteins (DPLs: DPP6 or DPPX, DPP10 or DPPY), enhance surface expression and modify functional properties. Since KChIP and DPL distributions overlap in the brain, we investigated the potential coassembly of Kv4.2, KChIP3 and DPL proteins, and the contribution of DPLs to ternary complex properties. Immunoprecipitation results show that KChIP3 and DPP10 associate simultaneously with Kv4.2 proteins in rat brain as well as heterologously expressing Xenopus oocytes, indicating Kv4.2 + KChIP3 + DPP10 multiprotein complexes. Consistent with ternary complex formation, coexpression of Kv4.2, KChIP3 and DPP10 in oocytes and CHO cells results in current waveforms distinct from the arithmetic sum of Kv4.2 + KChIP3 and Kv4.2 + DPP10 currents. Furthermore, the Kv4.2 + KChIP3 + DPP10 channels recover from inactivation very rapidly (tau(rec) approximately 18-26 ms), closely matching that of native I(SA) and significantly faster than the recovery of Kv4.2 + KChIP3 or Kv4.2 + DPP10 channels. For comparison, identical triple coexpression experiments were performed using DPP6 variants. While most results are similar, the Kv4.2 + KChIP3 + DPP6 channels exhibit inactivation that slows with increasing membrane potential, resulting in inactivation slower than that of Kv4.2 + KChIP3 + DPP10 channels at positive voltages. In conclusion, the native neuronal subthreshold A-type channel is probably a macromolecular complex formed from Kv4 and a combination of both KChIP and DPL proteins, with the precise composition of channel alpha and auxiliary subunits underlying tissue and regional variability in I(SA) properties.

  17. Synthesis of dimeric analogs of adenophostin A that potently evoke Ca2+ release through IP3 receptors† †Electronic supplementary information (ESI) available: NMR spectral data for all the new compounds. See DOI: 10.1039/c6ra19413c Click here for additional data file.

    PubMed Central

    Vibhute, Amol M.; Pushpanandan, Poornenth; Varghese, Maria; Koniecnzy, Vera; Taylor, Colin W.

    2016-01-01

    Inositol 1,4,5-trisphosphate receptors (IP3Rs) are tetrameric intracellular channels through which many extracellular stimuli initiate the Ca2+ signals that regulate diverse cellular responses. There is considerable interest in developing novel ligands of IP3R. Adenophostin A (AdA) is a potent agonist of IP3R and since some dimeric analogs of IP3R ligands are more potent than the corresponding monomer; we considered whether dimeric AdA analogs might provide agonists with increased potency. We previously synthesized traizolophostin, in which a simple triazole replaced the adenine of AdA, and showed it to be equipotent to AdA. Here, we used click chemistry to synthesize four homodimeric analogs of triazolophostin, connected by oligoethylene glycol chains of different lengths. We evaluated the potency of these analogs to release Ca2+ through type 1 IP3R and established that the newly synthesized dimers are equipotent to AdA and triazolophostin. PMID:28066549

  18. Negative regulation of DAB2IP by Akt and SCFFbw7 pathways.

    PubMed

    Dai, Xiangping; North, Brian J; Inuzuka, Hiroyuki

    2014-05-30

    Deletion of ovarian carcinoma 2/disabled homolog 2 (DOC-2/DAB2) interacting protein (DAB2IP), is a tumor suppressor that serves as a scaffold protein involved in coordinately regulating cell proliferation, survival and apoptotic pathways. DAB2IP is epigenetically down-regulated in a variety of tumors through the action of the histone methyltransferase EZH2. Although DAB2IP is transcriptionally down-regulated in a variety of tumors, it remains unclear if other mechanisms contribute to functional inactivation of DAB2IP. Here we demonstrate that DAB2IP can be functionally down-regulated by two independent mechanisms. First, we identified that Akt1 can phosphorylate DAB2IP on S847, which regulates the interaction between DAB2IP and its effector molecules H-Ras and TRAF2. Second, we demonstrated that DAB2IP can be degraded in part through ubiquitin-proteasome pathway by SCF(Fbw7). DAB2IP harbors two Fbw7 phosho-degron motifs, which can be regulated by the kinase, CK1δ. Our data hence indicate that in addition to epigenetic down-regulation, two additional pathways can functional inactivate DAB2IP. Given that DAB2IP has previously been identified to possess direct causal role in tumorigenesis and metastasis, our data indicate that a variety of pathways may pass through DAB2IP to govern cancer development, and therefore highlight DAB2IP agonists as potential therapeutic approaches for future anti-cancer drug development.

  19. The meaning and experience of stress among supported employment clients with mental health problems.

    PubMed

    Besse, Christine; Poremski, Daniel; Laliberté, Vincent; Latimer, Eric

    2018-05-01

    Many clinicians are concerned that competitive work may cause excessive stress for people with severe mental health problems. Individual Placement and Support (IPS) is acknowledged as the most effective model of supported employment for this population. The manner in which IPS clients define and experience employment-related stress is poorly understood. This qualitative study aims to explore how people with mental health problems receiving IPS services define and experience employment-related stress. We purposively sampled and interviewed 16 clients of an IPS programme, who had been competitively employed for more than 1 month. Data were collected between September 2014 and July 2015 in Montreal, Canada. Transcripts of semi-structured interviews were analysed using grounded theory methodology. IPS clients often defined stress similar to its common understanding: the result of experiencing prolonged or/and cumulative strains, or of an incongruence between efforts and rewards, hopes and reality. Stress experienced in this way could exacerbate psychiatric symptoms, especially depression or psychotic symptoms. However, when maintained at a more manageable level, stress stimulated learning and improved planning of tasks. Participants described different coping mechanisms, such as sharing their experiences and difficulties with others, focusing on problem resolution and avoidance. The first two of these helped IPS clients remain at work and bolstered their confidence. Work-related stress has potentially positive as well as negative consequences for IPS clients. In order to maximise the potential beneficial effects of stress, employment specialists can help clients anticipate potential stressors and plan how they might cope with them. Further research on the most effective ways of helping clients cope with stress is needed. © 2017 John Wiley & Sons Ltd.

  20. Opportunistic pathology-based screening for diabetes

    PubMed Central

    Simpson, Aaron J; Krowka, Renata; Kerrigan, Jennifer L; Southcott, Emma K; Wilson, J Dennis; Potter, Julia M; Nolan, Christopher J; Hickman, Peter E

    2013-01-01

    Objective To determine the potential of opportunistic glycated haemoglobin (HbA1c) testing of pathology samples to detect previously unknown diabetes. Design Pathology samples from participants collected for other reasons and suitable for HbA1c testing were utilised for opportunistic diabetes screening. HbA1c was measured with a Biorad Variant II turbo analyser and HbA1c levels of ≥6.5% (48 mmol/mol) were considered diagnostic for diabetes. Confirmation of previously unknown diabetes status was obtained by a review of hospital medical records and phone calls to general practitioners. Setting Hospital pathology laboratory receiving samples from hospital-based and community-based (CB) settings. Participants Participants were identified based on the blood sample collection location in the CB, emergency department (ED) and inpatient (IP) groups. Exclusions pretesting were made based on the electronic patient history of: age <18 years, previous diabetes diagnosis, query for diabetes status in the past 12 months, evidence of pregnancy and sample collected postsurgery or transfusion. Only one sample per individual participant was tested. Results Of the 22 396 blood samples collected, 4505 (1142 CB, 1113 ED, 2250 IP) were tested of which 327 (7.3%) had HbA1c levels ≥6.5% (48 mmol/mol). Of these 120 (2.7%) were determined to have previously unknown diabetes (11 (1%) CB, 21 (1.9%) ED, 88 (3.9%) IP). The prevalence of previously unknown diabetes was substantially higher (5.4%) in hospital-based (ED and IP) participants aged over 54 years. Conclusions Opportunistic testing of referred pathology samples can be an effective method of screening for diabetes, especially in hospital-based and older persons. PMID:24065696

  1. Excitation spectra of aromatic molecules within a real-space G W -BSE formalism: Role of self-consistency and vertex corrections

    DOE PAGES

    Hung, Linda; da Jornada, Felipe H.; Souto-Casares, Jaime; ...

    2016-08-15

    Here, we present first-principles calculations on the vertical ionization potentials (IPs), electron affinities (EAs), and singlet excitation energies on an aromatic-molecule test set (benzene, thiophene, 1,2,5-thiadiazole, naphthalene, benzothiazole, and tetrathiafulvalene) within the GW and Bethe-Salpeter equation (BSE) formalisms. Our computational framework, which employs a real-space basis for ground-state and a transition-space basis for excited-state calculations, is well suited for high-accuracy calculations on molecules, as we show by comparing against G0W0 calculations within a plane-wave-basis formalism. We then generalize our framework to test variants of the GW approximation that include a local density approximation (LDA)–derived vertex function (Γ LDA ) andmore » quasiparticle-self-consistent (QS) iterations. We find that Γ LDA and quasiparticle self-consistency shift IPs and EAs by roughly the same magnitude, but with opposite sign for IPs and the same sign for EAs. G0W0 and QS GWΓ LDA are more accurate for IPs, while G 0W 0Γ LDA and QS GW are best for EAs. For optical excitations, we find that perturbative GW-BSE underestimates the singlet excitation energy, while self-consistent GW-BSE results in good agreement with previous best-estimate values for both valence and Rydberg excitations. Finally, our work suggests that a hybrid approach, in which G0W0 energies are used for occupied orbitals and G0W0Γ LDA for unoccupied orbitals, also yields optical excitation energies in good agreement with experiment but at a smaller computational cost.« less

  2. Excitation spectra of aromatic molecules within a real-space G W -BSE formalism: Role of self-consistency and vertex corrections

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

    Hung, Linda; da Jornada, Felipe H.; Souto-Casares, Jaime

    Here, we present first-principles calculations on the vertical ionization potentials (IPs), electron affinities (EAs), and singlet excitation energies on an aromatic-molecule test set (benzene, thiophene, 1,2,5-thiadiazole, naphthalene, benzothiazole, and tetrathiafulvalene) within the GW and Bethe-Salpeter equation (BSE) formalisms. Our computational framework, which employs a real-space basis for ground-state and a transition-space basis for excited-state calculations, is well suited for high-accuracy calculations on molecules, as we show by comparing against G0W0 calculations within a plane-wave-basis formalism. We then generalize our framework to test variants of the GW approximation that include a local density approximation (LDA)–derived vertex function (Γ LDA ) andmore » quasiparticle-self-consistent (QS) iterations. We find that Γ LDA and quasiparticle self-consistency shift IPs and EAs by roughly the same magnitude, but with opposite sign for IPs and the same sign for EAs. G0W0 and QS GWΓ LDA are more accurate for IPs, while G 0W 0Γ LDA and QS GW are best for EAs. For optical excitations, we find that perturbative GW-BSE underestimates the singlet excitation energy, while self-consistent GW-BSE results in good agreement with previous best-estimate values for both valence and Rydberg excitations. Finally, our work suggests that a hybrid approach, in which G0W0 energies are used for occupied orbitals and G0W0Γ LDA for unoccupied orbitals, also yields optical excitation energies in good agreement with experiment but at a smaller computational cost.« less

  3. Using the Surprise Question To Identify Those with Unmet Palliative Care Needs in Emergency and Inpatient Settings: What Do Clinicians Think?

    PubMed

    Haydar, Samir A; Almeder, Lisa; Michalakes, Lauren; Han, Paul K J; Strout, Tania D

    2017-07-01

    The surprise question (SQ), "Would you be surprised if this patient died within the next year?" is effective in identifying end-stage renal disease and cancer patients at high risk of death and therefore potentially unmet palliative care needs. Following implementation of the SQ in our acute care setting, we sought to explore hospital-based providers' perceptions of the tool. To evaluate (1) providers' perceptions regarding the feasibility of SQ use in emergency and inpatient settings, (2) clinician perceptions regarding the utility of the SQ, and (3) barriers to SQ use. A cross-sectional survey of medical providers following addition of the SQ to the electronic record for all patients admitted to a tertiary care hospital. A total of 111/203 (55%) providers participated: 48/57 (84%) emergency physicians (EPs) and 63/146 (43%) inpatient providers (IPs). Most reported no difficulty using the SQ. Modest numbers in both groups reported that the SQ influenced care delivery (EPs 37%, IPs 42%) as well as goals of care (EPs 45%, IPs 52%). At least some advance care planning discussions were prompted by the SQ (EPs 45%, IPs 58%). Team discussions were influenced by SQ use for more than half of each group. Most respondents (55%) expressed some concern that their SQ responses could be inaccurate. In this setting, clinicians indicated that use of the SQ is feasible, acceptable, and useful in facilitating advance care planning discussions among teams, patients, and families. Many reported that SQ use influenced goals of care, but concern regarding accuracy was a barrier. Additional research examining SQ accuracy and predictive ability is warranted.

  4. How to Combine ChIP with qPCR.

    PubMed

    Asp, Patrik

    2018-01-01

    Chromatin immunoprecipitation (ChIP) coupled with quantitative PCR (qPCR) has in the last 15 years become a basic mainstream tool in genomic research. Numerous commercially available ChIP kits, qPCR kits, and real-time PCR systems allow for quick and easy analysis of virtually anything chromatin-related as long as there is an available antibody. However, the highly accurate quantitative dimension added by using qPCR to analyze ChIP samples significantly raises the bar in terms of experimental accuracy, appropriate controls, data analysis, and data presentation. This chapter will address these potential pitfalls by providing protocols and procedures that address the difficulties inherent in ChIP-qPCR assays.

  5. The electronic security partnership of safety/security and information systems departments.

    PubMed

    Yow, J Art

    2012-01-01

    The ever-changing world of security electronics is reviewed in this article. The author focuses on its usage in a hospital setting and the need for safety/security and information systems departments to work together to protect and get full value from IP systems.

  6. The PLC/IP3R/PKC Pathway is Required for Ethanol-enhanced GABA Release

    PubMed Central

    Kelm, M. Katherine; Weinberg, Richard J.; Criswell, Hugh E.; Breese, George R.

    2010-01-01

    Summary Research on the actions of ethanol at the GABAergic synapse has traditionally focused on postsynaptic mechanisms, but recent data demonstrate that ethanol also increases both evoked and spontaneous GABA release in many brain regions. Using whole-cell voltage-clamp recordings, we previously showed that ethanol increases spontaneous GABA release at the rat interneuron-Purkinje cell synapse. This presynaptic ethanol effect is dependent on calcium release from internal stores, possibly through activation of inositol 1,4,5-trisphosphate receptors (IP3Rs). After confirming that ethanol targets vesicular GABA release, in the present study we used electron microscopic immunohistochemistry to demonstrate that IP3Rs are located in presynaptic terminals of cerebellar interneurons. Activation of IP3Rs requires binding of IP3, generated through activation of phospholipase C (PLC). We find that the PLC antagonist edelfosine prevents ethanol from increasing spontaneous GABA release. Diacylglycerol generated by PLC and calcium released by activation of the IP3R activate protein kinase C (PKC). Ethanol-enhanced GABA release was blocked by two PKC antagonists, chelerythrine and calphostin C. When a membrane impermeable PKC antagonist, PKC (19-36), was delivered intracellularly to the postsynaptic neuron, ethanol continued to increase spontaneous GABA release. Overall, these results suggest that activation of the PLC/IP3R/PKC pathway is necessary for ethanol to increase spontaneous GABA release from presynaptic terminals onto Purkinje cells. PMID:20206640

  7. Density functional theory and phytochemical study of 8-hydroxyisodiospyrin

    NASA Astrophysics Data System (ADS)

    Ullah, Zakir; Ata-ur-Rahman; Fazl-i-Sattar; Rauf, Abdur; Yaseen, Muhammad; Hassan, Waseem; Tariq, Muhammad; Ayub, Khurshid; Tahir, Asif Ali; Ullah, Habib

    2015-09-01

    Comprehensive theoretical and experimental studies of a natural product, 8-hydroxyisodiospyrin (HDO) have been carried out. Based on the correlation of experimental and theoretical data, an appropriate computational model was developed for obtaining the electronic, spectroscopic, and thermodynamic parameters of HDO. First of all, the exact structure of HDO is confirmed from the nice correlation of theory and experiment, prior to determination of its electroactive nature. Hybrid density functional theory (DFT) is employed for all theoretical simulations. The experimental and predicted IR and UV-vis spectra [B3LYP/6-31+G(d,p) level of theory] have excellent correlation. Inter-molecular non-covalent interaction of HDO with different gases such as NH3, CO2, CO, H2O is investigated through geometrical counterpoise (gCP) i.e., B3LYP-gCP-D3/6-31G∗ method. Furthermore, the inter-molecular interaction is also supported by geometrical parameters, electronic properties, thermodynamic parameters and charge analysis. All these characterizations have corroborated each other and confirmed the electroactive nature (non-covalent interaction ability) of HDO for the studied gases. Electronic properties such as Ionization Potential (IP), Electron Affinities (EA), electrostatic potential (ESP), density of states (DOS), HOMO, LUMO, and band gap of HDO have been estimated for the first time theoretically.

  8. Phytochemical, spectroscopic and density functional theory study of Diospyrin, and non-bonding interactions of Diospyrin with atmospheric gases.

    PubMed

    Fazl-i-Sattar; Ullah, Zakir; Ata-ur-Rahman; Rauf, Abdur; Tariq, Muhammad; Tahir, Asif Ali; Ayub, Khurshid; Ullah, Habib

    2015-04-15

    Density functional theory (DFT) and phytochemical study of a natural product, Diospyrin (DO) have been carried out. A suitable level of theory was developed, based on correlating the experimental and theoretical data. Hybrid DFT method at B3LYP/6-31G (d,p) level of theory is employed for obtaining the electronic, spectroscopic, inter-molecular interaction and thermodynamic properties of DO. The exact structure of DO is confirmed from the nice validation of the theory and experiment. Non-covalent interactions of DO with different atmospheric gases such as NH3, CO2, CO, and H2O were studied to find out its electroactive nature. The experimental and predicted geometrical parameters, IR and UV-vis spectra (B3LYP/6-31+G (d,p) level of theory) show excellent correlation. Inter-molecular non-bonding interaction of DO with atmospheric gases is investigated through geometrical parameters, electronic properties, charge analysis, and thermodynamic parameters. Electronic properties include, ionization potential (I.P.), electron affinities (E.A.), electrostatic potential (ESP), density of states (DOS), HOMO, LUMO, and band gap. All these characterizations have corroborated each other and confirmed the presence of non-covalent nature in DO with the mentioned gases. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Mixed Matrix Membranes of Boron Icosahedron and Polymers of Intrinsic Microporosity (PIM-1) for Gas Separation

    PubMed Central

    Khan, Muntazim Munir; Shishatskiy, Sergey; Filiz, Volkan

    2018-01-01

    This work reports on the preparation and gas transport performance of mixed matrix membranes (MMMs) based on the polymer of intrinsic microporosity (PIM-1) and potassium dodecahydrododecaborate (K2B12H12) as inorganic particles (IPs). The effect of IP loading on the gas separation performance of these MMMs was investigated by varying the IP content (2.5, 5, 10 and 20 wt %) in a PIM-1 polymer matrix. The derived MMMs were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), single gas permeation tests and sorption measurement. The PIM1/K2B12H12 MMMs show good dispersion of the IPs (from 2.5 to 10 wt %) in the polymer matrix. The gas permeability of PIM1/K2B12H12 MMMs increases as the loading of IPs increases (up to 10 wt %) without sacrificing permselectivity. The sorption isotherm in PIM-1 and PIM1/K2B12H12 MMMs demonstrate typical dual-mode sorption behaviors for the gases CO2 and CH4. PMID:29301312

  10. Doubling the Spectrum of Time-Domain Induced Polarization: Removal of Harmonic Noise and Self-Potential Drift

    NASA Astrophysics Data System (ADS)

    Fiandaca, G.; Olsson, P. I.; Auken, E.; Larsen, J. J.; Maurya, P. K.; Dahlin, T.

    2015-12-01

    The extraction of spectral information in the inversion process of time-domain (TD) induced polarization (IP) data is changing the use of the IP method. Data interpretation is evolving from a qualitative description of the soil, able only to discriminate the presence of contrasts in chargeability parameters, towards a quantitative analysis of the investigated media, which allows soil-type characterization. Two major limitations restrict the extraction of the spectral information of TDIP data in the field: i) the difficulty of acquiring reliable early-time measurements, in the millisecond range and ii) the self-potential drift in the measured potentials distorting the shape of the late time IP decays, in the second range. For measuring at early-times, we developed a new method for removing the powerline noise contained in the data through a model-based approach, localizing the fundamental frequency of the powerline signal in the full-waveform IP recordings. By this, we cancel both the fundamental signal and its harmonics. This noise cancellation allows the use of earlier and narrower gates, down to a few milliseconds after the current turn-off. Even earlier gates can be measured but they will be inductively "contaminated" which we at present want to avoid. A proper removal of the self-potential drift present between the potential electrodes is essential for preserving the shape of the TD decays, especially for late times. Usually constant or linear drift-removal algorithms are used, but these algorithms fail in removing the background potentials due to the polarization of the electrodes previously used for current injection. We developed a drift-removal scheme that model the polarization effect and efficiently allows for preserving the shape of the IP decays. The removal of both the harmonic noise and self-potential drift allows for doubling the usable range of TDIP data to more than three decades in time (corresponding to three decays in frequency), and will significantly advance the science and the applicability of the IP method in exploration and environmental geophysics.

  11. Investigations of a Cretaceous limestone with spectral induced polarization and scanning electron microscopy

    NASA Astrophysics Data System (ADS)

    Johansson, Sara; Sparrenbom, Charlotte; Fiandaca, Gianluca; Lindskog, Anders; Olsson, Per-Ivar; Dahlin, Torleif; Rosqvist, Håkan

    2017-02-01

    Characterization of varying bedrock properties is a common need in various contexts, ranging from large infrastructure pre-investigations to environmental protection. A direct current resistivity and time domain induced polarization (IP) survey aiming to characterize properties of a Cretaceous limestone was carried out in the Kristianstad basin, Sweden. The time domain IP data was processed with a recently developed method in order to suppress noise from the challenging urban setting in the survey area. The processing also enabled extraction of early decay times resulting in broader spectra of the time decays and inversion for Cole-Cole parameters. The aims of this study is to investigate if large-scale geoelectrical variations as well as small-scale structural and compositional variations exist within the Kristianstad limestone, and to evaluate the usefulness of Cole-Cole inverted IP data in early time ranges for bedrock characterization. The inverted sections showed variations within the limestone that could be caused by variations in texture and composition. Samples from a deep drilling in the Kristianstad basin were investigated with scanning electron microscopy and energy dispersive X-ray spectroscopy, and the results showed that varying amounts of pyrite, glauconite and clay matrix were present at different levels in the limestone. The local high IP anomalies in the limestone could be caused by these minerals otherwise the IP responses were generally weak. There were also differences in the texture of the limestone at different levels, governed by fossil shapes and composition, proportions of calcareous cement and matrix as well as amount of silicate grains. Textural variations may have implications on the variation in Cole-Cole relaxation time and frequency factor. However, more research is needed in order to directly connect microgeometrical properties in limestone to spectral IP responses. The results from this study show that it is possible to recover useable spectral information from early decay times. We also show that under certain conditions (e.g. relatively short relaxation times in the subsurface), it is possible to extract spectral information from time domain IP data measured with on-off times as short as 1 s.

  12. Doubling the spectrum of time-domain induced polarization by harmonic de-noising, drift correction, spike removal, tapered gating and data uncertainty estimation

    NASA Astrophysics Data System (ADS)

    Olsson, Per-Ivar; Fiandaca, Gianluca; Larsen, Jakob Juul; Dahlin, Torleif; Auken, Esben

    2016-11-01

    The extraction of spectral information in the inversion process of time-domain (TD) induced polarization (IP) data is changing the use of the TDIP method. Data interpretation is evolving from a qualitative description of the subsurface, able only to discriminate the presence of contrasts in chargeability parameters, towards a quantitative analysis of the investigated media, which allows for detailed soil- and rock-type characterization. Two major limitations restrict the extraction of the spectral information of TDIP data in the field: (i) the difficulty of acquiring reliable early-time measurements in the millisecond range and (ii) the self-potential background drift in the measured potentials distorting the shape of the late-time IP responses, in the second range. Recent developments in TDIP acquisition equipment have given access to full-waveform recordings of measured potentials and transmitted current, opening for a breakthrough in data processing. For measuring at early times, we developed a new method for removing the significant noise from power lines contained in the data through a model-based approach, localizing the fundamental frequency of the power-line signal in the full-waveform IP recordings. By this, we cancel both the fundamental signal and its harmonics. Furthermore, an efficient processing scheme for identifying and removing spikes in TDIP data was developed. The noise cancellation and the de-spiking allow the use of earlier and narrower gates, down to a few milliseconds after the current turn-off. In addition, tapered windows are used in the final gating of IP data, allowing the use of wider and overlapping gates for higher noise suppression with minimal distortion of the signal. For measuring at late times, we have developed an algorithm for removal of the self-potential drift. Usually constant or linear drift-removal algorithms are used, but these algorithms often fail in removing the background potentials present when the electrodes used for potential readings are previously used for current injection, also for simple contact resistance measurements. We developed a drift-removal scheme that models the polarization effect and efficiently allows for preserving the shape of the IP responses at late times. Uncertainty estimates are essential in the inversion of IP data. Therefore, in the final step of the data processing, we estimate the data standard deviation based on the data variability within the IP gates and the misfit of the background drift removal Overall, the removal of harmonic noise, spikes, self-potential drift, tapered windowing and the uncertainty estimation allows for doubling the usable range of TDIP data to almost four decades in time (corresponding to four decades in frequency), which will significantly advance the applicability of the IP method.

  13. Centriolar satellite– and hMsd1/SSX2IP-dependent microtubule anchoring is critical for centriole assembly

    PubMed Central

    Hori, Akiko; Peddie, Christopher J.; Collinson, Lucy M.; Toda, Takashi

    2015-01-01

    Centriolar satellites are numerous electron-dense granules dispersed around the centrosome. Mutations in their components are linked to various human diseases, but their molecular roles remain elusive. In particular, the significance of spatial communication between centriolar satellites and the centrosome is unknown. hMsd1/SSX2IP localizes to both the centrosome and centriolar satellites and is required for tethering microtubules to the centrosome. Here we show that hMsd1/SSX2IP-mediated microtubule anchoring is essential for proper centriole assembly and duplication. On hMsd1/SSX2IP knockdown, the centriolar satellites become stuck at the microtubule minus end near the centrosome. Intriguingly, these satellites contain many proteins that normally localize to the centrosome. Of importance, microtubule structures, albeit not being anchored properly, are still required for the emergence of abnormal satellites, as complete microtubule depolymerization results in the disappearance of these aggregates from the vicinity of the centrosome. We highlighted, using superresolution and electron microscopy, that under these conditions, centriole structures are faulty. Remarkably, these cells are insensitive to Plk4 overproduction–induced ectopic centriole formation, yet they accelerate centrosome reduplication upon hydroxyurea arrest. Finally, the appearance of satellite aggregates is cancer cell specific. Together our findings provide novel insights into the mechanism of centriole assembly and microtubule anchoring. PMID:25833712

  14. Study of gas-phase O-H bond dissociation enthalpies and ionization potentials of substituted phenols - Applicability of ab initio and DFT/B3LYP methods

    NASA Astrophysics Data System (ADS)

    Klein, Erik; Lukeš, Vladimír

    2006-11-01

    In this paper, the study of phenol and 37 compounds representing various ortho-, para-, and meta-substituted phenols is presented. Molecules and their radical structures were studied using ab initio methods with inclusion of correlation energy and DFT in order to calculate the O-H bond dissociation enthalpies (BDEs) and vertical ionization potentials (IPs). Calculated BDEs and IPs were compared with available experimental values to ascertain the suitability of used methods, especially for the description of the substituent induced changes in BDE and IP. MP2, MP3, and MP4 methods do not give reliable results, since they significantly underestimate substituent induced changes in BDE and do not reflect distinct effect of substituents related to para and meta position correctly. DFT/B3LYP method reflects the effect of substituents on BDE satisfactorily, though ΔBDEs are in narrower range than experimental values. BDE of phenol was calculated also using CCSD(T) method in various basis sets. Both, DFT and HF methods describe the effect of substituents on IP identically. However, DFT considerably underestimates individual values. HF method gives IPs in very good agreement with experimental data. Obtained results show that dependences of BDEs and IPs on Hammett constants of the substituents are linear. Linearity of DFT BDE vs. IP dependence is even better than the dependences on Hammett constants and obtained equations allow estimating of O-H BDEs of meta- and para-substituted phenols from calculated IPs.

  15. Audio CAPTCHA for SIP-Based VoIP

    NASA Astrophysics Data System (ADS)

    Soupionis, Yannis; Tountas, George; Gritzalis, Dimitris

    Voice over IP (VoIP) introduces new ways of communication, while utilizing existing data networks to provide inexpensive voice communications worldwide as a promising alternative to the traditional PSTN telephony. SPam over Internet Telephony (SPIT) is one potential source of future annoyance in VoIP. A common way to launch a SPIT attack is the use of an automated procedure (bot), which generates calls and produces audio advertisements. In this paper, our goal is to design appropriate CAPTCHA to fight such bots. We focus on and develop audio CAPTCHA, as the audio format is more suitable for VoIP environments and we implement it in a SIP-based VoIP environment. Furthermore, we suggest and evaluate the specific attributes that audio CAPTCHA should incorporate in order to be effective, and test it against an open source bot implementation.

  16. The auxiliary subunit KChIP2 is an essential regulator of homeostatic excitability.

    PubMed

    Wang, Hong-Gang; He, Xiao Ping; Li, Qiang; Madison, Roger D; Moore, Scott D; McNamara, James O; Pitt, Geoffrey S

    2013-05-10

    The necessity for, or redundancy of, distinctive KChIP proteins is not known. Deletion of KChIP2 leads to increased susceptibility to epilepsy and to a reduction in IA and increased excitability in pyramidal hippocampal neurons. KChIP2 is essential for homeostasis in hippocampal neurons. Mutations in K(A) channel auxiliary subunits may be loci for epilepsy. The somatodendritic IA (A-type) K(+) current underlies neuronal excitability, and loss of IA has been associated with the development of epilepsy. Whether any one of the four auxiliary potassium channel interacting proteins (KChIPs), KChIP1-KChIP4, in specific neuronal populations is critical for IA is not known. Here we show that KChIP2, which is abundantly expressed in hippocampal pyramidal cells, is essential for IA regulation in hippocampal neurons and that deletion of Kchip2 affects susceptibility to limbic seizures. The specific effects of Kchip2 deletion on IA recorded from isolated hippocampal pyramidal neurons were a reduction in amplitude and shift in the V½ for steady-state inactivation to hyperpolarized potentials when compared with WT neurons. Consistent with the relative loss of IA, hippocampal neurons from Kchip2(-/-) mice showed increased excitability. WT cultured neurons fired only occasional single action potentials, but the average spontaneous firing rate (spikes/s) was almost 10-fold greater in Kchip2(-/-) neurons. In slice preparations, spontaneous firing was detected in CA1 pyramidal neurons from Kchip2(-/-) mice but not from WT. Additionally, when seizures were induced by kindling, the number of stimulations required to evoke an initial class 4 or 5 seizure was decreased, and the average duration of electrographic seizures was longer in Kchip2(-/-) mice compared with WT controls. Together, these data demonstrate that the KChIP2 is essential for physiologic IA modulation and homeostatic stability and that there is a lack of functional redundancy among the different KChIPs in hippocampal neurons.

  17. Electronic Reference Library: Silverplatter's Database Networking Solution.

    ERIC Educational Resources Information Center

    Millea, Megan

    Silverplatter's Electronic Reference Library (ERL) provides wide area network access to its databases using TCP/IP communications and client-server architecture. ERL has two main components: The ERL clients (retrieval interface) and the ERL server (search engines). ERL clients provide patrons with seamless access to multiple databases on multiple…

  18. Prognostic value of CtIP/RBBP8 expression in breast cancer

    PubMed Central

    Soria-Bretones, Isabel; Sáez, Carmen; Ruíz-Borrego, Manuel; Japón, Miguel A; Huertas, Pablo

    2013-01-01

    CtIP/RBBP8 is a multifunctional protein involved in transcription, DNA replication, DNA repair by homologous recombination and the G1 and G2 checkpoints. Its multiple roles are controlled by its interaction with several specific factors, including the tumor suppressor proteins BRCA1 and retinoblastoma. Both its functions and interactors point to a putative oncogenic potential of CtIP/RBBP8 loss. However, CtIP/RBBP8 relevance in breast tumor appearance, development, and prognosis has yet to be established. We performed a retrospective analysis of CtIP/RBBP8 and RB1 levels by immunohistochemistry using 384 paraffin-embedded breast cancer biopsies obtained during tumor removal surgery. We have observed that low or no expression of CtIP/RBBP8 correlates with high-grade breast cancer and with nodal metastasis. Reduction on CtIP/RBBP8 is most common in hormone receptor (HR)-negative, HER2-positive, and basal-like tumors. We observed lower levels of RB1 on those tumors with reduced CtIP/RBBP8 levels. On luminal tumors, decreased but not absence of CtIP/RBBP8 levels correlate with increased disease-free survival when treated with a combination of hormone, radio, and chemo therapies. PMID:24403251

  19. Inhibition of P-Glycoprotein Mediated Efflux in Caco-2 Cells by Phytic Acid.

    PubMed

    Li, Lujia; Fu, Qingxue; Xia, Mengxin; Xin, Lei; Shen, Hongyi; Li, Guowen; Ji, Guang; Meng, Qianchao; Xie, Yan

    2018-01-31

    Phytic acid (IP6) is a natural phosphorylated inositol, which is abundantly present in most cereal grains and seeds. This study investigated the effects of IP6 regulation on P-glycoprotein (P-gp) and its potential mechanisms using in situ and in vitro models. The effective permeability of the typical P-gp substrate rhodamine 123 (R123) in colon was significantly increased from (1.69 ± 0.22) × 10 -5 cm/s in the control group to (3.39 ± 0.417) × 10 -5 cm/s (p < 0.01) in the 3.5 mM IP6 group. Additionally, IP6 can concentration-dependently decrease the R123 efflux ratio in both Caco-2 and MDCK II-MDR1 cell monolayers and increase intracellular R123 accumulation in Caco-2 cells. Furthermore, IP6 noncompetitively inhibited P-gp by impacting R123 efflux kinetics. The noncompetitive inhibition of P-gp by IP6 was likely due to decreases in P-gp ATPase activity and P-gp molecular conformational changes induced by IP6. In summary, IP6 is a promising P-gp inhibitor candidate.

  20. Biological activities of the polysaccharides produced in submerged culture of two edible Pleurotus ostreatus mushrooms.

    PubMed

    Vamanu, Emanuel

    2012-01-01

    Exopolysaccharides (EPS) and internal (intracellular) polysaccharides (IPS) obtained from the Pleurotus ostreatus M2191 and PBS281009 cultivated using the batch system revealed an average of between 0.1-2 (EPS) and 0.07-1.5 g/L/day (IPS). The carbohydrate analysis revealed that the polysaccharides comprised 87-89% EPS and 68-74% IPS. The investigation of antioxidant activity in vitro revealed a good antioxidant potential, particularly for the IPS and EPS isolated from PBS281009, as proved by the EC(50) value for DPPH, ABTS scavenging activity, reducing power, and iron chelating activity.

  1. Regulation of myeloid leukemia factor-1 interacting protein (MLF1IP) expression in glioblastoma.

    PubMed

    Hanissian, Silva H; Teng, Bin; Akbar, Umar; Janjetovic, Zorica; Zhou, Qihong; Duntsch, Christopher; Robertson, Jon H

    2005-06-14

    The myelodysplasia/myeloid leukemia factor 1-interacting protein MLF1IP is a novel gene which encodes for a putative transcriptional repressor. It is localized to human chromosome 4q35.1 and is expressed in both the nuclei and cytoplasm of cells. Northern and Western blot analyses have revealed MLF1IP to be present at very low amounts in normal brain tissues, whereas a number of human and rat glioblastoma (GBM) cell lines demonstrated a high level expression of the MLF1IP protein. Immunohistochemical analysis of rat F98 and C6 GBM tumor models showed that MLF1IP was highly expressed in the tumor core where it was co-localized with MLF1 and nestin. Moreover, MLF1IP expression was elevated in the contralateral brain where no tumor cells were detected. These observations, together with previous data demonstrating a role for MLF1IP in erythroleukemias, suggest a possible function for this protein in glioma pathogenesis and potentially in other types of malignancies.

  2. DNA damage response curtails detrimental replication stress and chromosomal instability induced by the dietary carcinogen PhIP

    PubMed Central

    Mimmler, Maximilian; Peter, Simon; Kraus, Alexander; Stroh, Svenja; Nikolova, Teodora; Seiwert, Nina; Hasselwander, Solveig; Neitzel, Carina; Haub, Jessica; Monien, Bernhard H.; Nicken, Petra; Steinberg, Pablo; Shay, Jerry W.; Kaina, Bernd; Fahrer, Jörg

    2016-01-01

    PhIP is an abundant heterocyclic aromatic amine (HCA) and important dietary carcinogen. Following metabolic activation, PhIP causes bulky DNA lesions at the C8-position of guanine. Although C8-PhIP-dG adducts are mutagenic, their interference with the DNA replication machinery and the elicited DNA damage response (DDR) have not yet been studied. Here, we analyzed PhIP-triggered replicative stress and elucidated the role of the apical DDR kinases ATR, ATM and DNA-PKcs in the cellular defense response. First, we demonstrate that PhIP induced C8-PhIP-dG adducts and DNA strand breaks. This stimulated ATR-CHK1 signaling, phosphorylation of histone 2AX and the formation of RPA foci. In proliferating cells, PhIP treatment increased the frequency of stalled replication forks and reduced fork speed. Inhibition of ATR in the presence of PhIP-induced DNA damage strongly promoted the formation of DNA double-strand breaks, activation of the ATM-CHK2 pathway and hyperphosphorylation of RPA. The abrogation of ATR signaling potentiated the cell death response and enhanced chromosomal aberrations after PhIP treatment, while ATM and DNA-PK inhibition had only marginal effects. These results strongly support the notion that ATR plays a key role in the defense against cancer formation induced by PhIP and related HCAs. PMID:27599846

  3. Standardization efforts in IP telephony

    NASA Astrophysics Data System (ADS)

    Sengodan, Senthil; Bansal, Raj

    1999-11-01

    The recent interest in IP telephony has led to a tremendous increase of standardization activities in the area. The three main standards bodies in the area of IP telephony are the International Telecommunication Union's (ITU-T) Study Group (SG) 16, the Internet Engineering Task Force (IETF) and the European Telecommunication Standards Institute's (ETSI) TIPHON project. In addition, forums such as the International Multimedia Teleconferencing Consortium (IMTC), the Intelligent Network Forum (INF), the International Softswitch Consortium (ISC), the Electronic Computer Telephony Forum (ECTF), and the MIT's Internet Telephony Consortium (ITC) are looking into various other aspects that aim at the growth of this industry. This paper describes the main tasks (completed and in progress) undertaken by these organizations. In describing such work, an overview of the underlying technology is also provided.

  4. Effects of memantine on hippocampal long-term potentiation, gamma activity, and sensorimotor gating in freely moving rats.

    PubMed

    Ma, Jingyi; Mufti, Asfandyar; Stan Leung, L

    2015-09-01

    Memantine, an uncompetitive N-methyl-D-aspartate receptor antagonist, is used for treatment of patients with Alzheimer's disease. The mechanisms of memantine in relieving cognitive and behavioral symptoms are unclear, and this study attempts to elucidate its action on network and synaptic functions of the hippocampus. The effects of memantine on electrographic activity and hippocampal long-term potentiation (LTP) were investigated in freely moving rats. Basal dendritic excitation on hippocampal CA1 pyramidal cells showed a robust LTP after theta-frequency primed bursts, and the LTP was higher after 5-10 mg/kg intraperitoneal (ip) memantine pretreatment, as compared with saline pretreatment. Injection of scopolamine (5 mg/kg ip) before memantine failed to block the LTP-enhancing effect of memantine. Memantine as compared with saline pretreatment did not affect the LTP after an afterdischarge induced by high-frequency (200-Hz) train stimulation. Memantine (5 or 10 mg/kg ip) significantly enhanced gamma oscillations in the hippocampal local field potentials of 40-100 Hz during walking and awake immobility. Memantine at 10 mg/kg ip, but not at 5 mg/kg ip, increased prepulse inhibition of the acoustic startle response, while both 5 and 10 mg/kg ip memantine enhanced the acoustic startle response as compared with saline-injected rats. These electrophysiological and behavioral effects of memantine are unique among N-methyl-D-aspartate receptor antagonists but are consistent with memantine's effects in improving cognitive and sensorimotor functions of Alzheimer's patients. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Voice over Internet protocol for the orthodontic practice: a sensible switch from plain old telephone service.

    PubMed

    Mupparapu, Muralidhar

    2008-03-01

    Voice over Internet protocol (VoIP) is a revolutionary new technology that is causing a stir in the telecommunications industry and threatening the existence of traditional telephone service providers. Based on a simple method of converting analog audio signals into digital data before being transmitted over the Internet, VoIP has gained immense popularity among consumers. The technology is now regarded as an alternative to traditional telephone service for the orthodontic office. When the economics are considered, it is cost-effective, especially for a busy orthodontic practice where the call volumes both in and out are always high. VoIP has the potential to reduce costs, break the barriers between local vs long-distance calling, and make life easier for the office staff. However, deploying VoIP requires a cautious and thought-out process. Users should fully understand the risks and benefits before switching from the public switched telephone network. VoIP customers and service providers are vulnerable to many of the same impersonation-based attacks by those who attempt toll fraud, and identity and information theft. In this article, VoIP is introduced to orthodontic practitioners, who might be unfamiliar with this technology. Internet protocol based private branch exchange systems that are currently marketed as open-source technologies are also reviewed. Additionally, VoIP is compared with the traditional public switched telephone network technology and evaluated for its potential applications in an orthodontic office for both increased efficiency and cost savings.

  6. Real-time Upstream Monitoring System: Using ACE Data to Predict the Arrival of Interplanetary Shocks

    NASA Astrophysics Data System (ADS)

    Donegan, M. M.; Wagstaff, K. L.; Ho, G. C.; Vandegriff, J.

    2003-12-01

    We have developed an algorithm to predict Earth arrival times for interplanetary (IP) shock events originating at the Sun. Our predictions are generated from real-time data collected by the Electron, Proton, and Alpha Monitor (EPAM) instrument on NASA's Advanced Composition Explorer (ACE) spacecraft. The high intensities of energetic ions that occur prior to and during an IP shock pose a radiation hazard to astronauts as well as to electronics in Earth orbit. The potential to predict such events is based on characteristic signatures in the Energetic Storm Particle (ESP) event ion intensities which are often associated with IP shocks. We have previously reported on the development and implementation of an algorithm to forecast the arrival of ESP events. Historical ion data from ACE/EPAM was used to train an artificial neural network which uses the signature of an approaching event to predict the time remaining until the shock arrives. Tests on the trained network have been encouraging, with an average error of 9.4 hours for predictions made 24 hours in advance, and an reduced average error of 4.9 hours when the shock is 12 hours away. The prediction engine has been integrated into a web-based system that uses real-time ACE/EPAM data provided by the NOAA Space Environment Center (http://sd-www.jhuapl.edu/UPOS/RISP/ index.html.) This system continually processes the latest ACE data, reports whether or not there is an impending shock, and predicts the time remaining until the shock arrival. Our predictions are updated every five minutes and provide significant lead-time, thereby supplying critical information that can be used by mission planners, satellite operations controllers, and scientists. We have continued to refine the prediction capabilities of this system; in addition to forecasting arrival times for shocks, we now provide confidence estimates for those predictions.

  7. An improved ChIP-seq peak detection system for simultaneously identifying post-translational modified transcription factors by combinatorial fusion, using SUMOylation as an example.

    PubMed

    Cheng, Chia-Yang; Chu, Chia-Han; Hsu, Hung-Wei; Hsu, Fang-Rong; Tang, Chung Yi; Wang, Wen-Ching; Kung, Hsing-Jien; Chang, Pei-Ching

    2014-01-01

    Post-translational modification (PTM) of transcriptional factors and chromatin remodelling proteins is recognized as a major mechanism by which transcriptional regulation occurs. Chromatin immunoprecipitation (ChIP) in combination with high-throughput sequencing (ChIP-seq) is being applied as a gold standard when studying the genome-wide binding sites of transcription factor (TFs). This has greatly improved our understanding of protein-DNA interactions on a genomic-wide scale. However, current ChIP-seq peak calling tools are not sufficiently sensitive and are unable to simultaneously identify post-translational modified TFs based on ChIP-seq analysis; this is largely due to the wide-spread presence of multiple modified TFs. Using SUMO-1 modification as an example; we describe here an improved approach that allows the simultaneous identification of the particular genomic binding regions of all TFs with SUMO-1 modification. Traditional peak calling methods are inadequate when identifying multiple TF binding sites that involve long genomic regions and therefore we designed a ChIP-seq processing pipeline for the detection of peaks via a combinatorial fusion method. Then, we annotate the peaks with known transcription factor binding sites (TFBS) using the Transfac Matrix Database (v7.0), which predicts potential SUMOylated TFs. Next, the peak calling result was further analyzed based on the promoter proximity, TFBS annotation, a literature review, and was validated by ChIP-real-time quantitative PCR (qPCR) and ChIP-reChIP real-time qPCR. The results show clearly that SUMOylated TFs are able to be pinpointed using our pipeline. A methodology is presented that analyzes SUMO-1 ChIP-seq patterns and predicts related TFs. Our analysis uses three peak calling tools. The fusion of these different tools increases the precision of the peak calling results. TFBS annotation method is able to predict potential SUMOylated TFs. Here, we offer a new approach that enhances ChIP-seq data analysis and allows the identification of multiple SUMOylated TF binding sites simultaneously, which can then be utilized for other functional PTM binding site prediction in future.

  8. Using Instant Messaging Systems as a Platform for Electronic Voting

    NASA Astrophysics Data System (ADS)

    Meletiadou, Anastasia; Grimm, Rüdiger

    Many Instant Messaging (IM) systems like Skype or Spark offer ex tended services such as file sharing, VoIP, or a shared whiteboard. As the name suggests, IM applications are predominantly used for spontaneous text-based communication for private or business purposes. In this paper we explore their potential to serve as platforms for secure collaborative applications like electronic contract negotiation, e-payment or electronic voting. Such applications have to deal with challenges like time constraints (“instant” com munication is desired), integration of media channels and the absence of one uni fying “sphere of control” covering all participants. In this paper, we address these challenges by discussing one particular secure collaborative application: secure decision processes for small groups. We provide the following contribu tions: (1) we define three varying scenarios and corresponding security require ments (2) we present an IM-based architecture implementing these scenarios, in cluding a Video-based authentication mechanism, and (3) we discuss poten tial attack patterns.

  9. Dependences of Ratio of the Luminosity to Ionization on Velocity and Chemical Composition of Meteors

    NASA Technical Reports Server (NTRS)

    Narziev, M.

    2011-01-01

    On the bases of results simultaneous photographic and radio echo observations, the results complex radar and television observations of meteors and also results of laboratory modeling of processes of a luminescence and ionization, correlation between of luminous intensity Ip to linear electronic density q from of velocities and chemical structure are investigated. It is received that by increasing value of velocities of meteors and decrease of nuclear weight of substance of particles, lg Ip/q decreased more than one order.

  10. [Modulation of Kv4 channels by KChIPs clamping].

    PubMed

    Cui, Yuan-Yuan; Wang, Ke-Wei

    2009-01-01

    The rapidly inactivating (A-type) potassium channels regulate membrane excitability that defines the fundamental mechanism of neuronal functions such as pain signaling. Cytosolic Kv channel-interacting proteins KChIPs co-assemble with Kv4 (Shal) alpha subunits to form a native complex. The specific binding of auxiliary KChIPs to the Kv4 N-terminus results in modulation of gating properties, surface expression and subunit assembly of Kv4 channels. Based on recent structural efforts, here we attempt to emphasize the interaction between KChIPs and Kv4 channel complex in which a single KChIP1 molecule laterally clamps two neighboring Kv4.3 N-termini in a 4:4 manner. Greater insights into molecular mechanism between KChIPs and Kv4 interaction may provide therapeutic potentials by structure-based design of chemical compounds aimed at disrupting the protein-protein interaction for treatment of membrane excitability-related disorders.

  11. The synergistic effect of micro/nano-structured and Cu2+-doped hydroxyapatite particles to promote osteoblast viability and antibacterial activity.

    PubMed

    Shi, Feng; Liu, Yumei; Zhi, Wei; Xiao, Dongqin; Li, Hongyu; Duan, Ke; Qu, Shuxin; Weng, Jie

    2017-06-06

    Microstructure and chemical constitution are important factors affecting the biological activity of biomaterials. This study aimed to fabricate hydroxyapatite (HAp) particles with both micro/nanohybrid structure and Cu 2+ doping to promote osteogenic differentiation and antibacterial property. In the presence of inositol hexakisphosphate (IP6), micro/nano-structured and Cu 2+ -doped HAp (HAp-IP6-Cu) microspheres were successfully fabricated via hydrothermal method. Morphological observation showed that HAp-IP6-Cu microspheres with a diameter of 3.1-4.1 μm were chrysanthemum-like and composed of nano-flakes approximately 50 nm in thickness. Compared with the HAp micro-rods or IP6 modified HAp (HAp-IP6) microspheres, HAp-IP6-Cu microspheres had a larger specific surface area, better hydrophilicity and stronger ability to adsorb bovine serum albumin. To evaluate the synergistic effects of micro/nanohybrid structure and Cu 2+ on cell behavior, rat calvarial osteoblasts (RCOs) were cultured on HAp-IP6-Cu, HAp-IP6 and HAp layers as well as their extracts, respectively. Results demonstrated that HAp-IP6-Cu layer promoted the adhesion, proliferation and osteogenic differentiation of RCOs. The cells grew on HAp-IP6-Cu and HAp-IP6 layers exhibited greater spreading than those on HAp layer. In addition, quantitative test by the agar disk diffusion technique found that HAp-IP6-Cu microspheres were effectively against S taphylococcus aureus and E scherichia coli. These results demonstrated that HAp-IP6-Cu microspheres may be a potential candidate as a bioactive and anti-infective biomaterial for bone regeneration.

  12. Preservation of cardiac function by prolonged action potentials in mice deficient of KChIP2.

    PubMed

    Grubb, Søren; Aistrup, Gary L; Koivumäki, Jussi T; Speerschneider, Tobias; Gottlieb, Lisa A; Mutsaers, Nancy A M; Olesen, Søren-Peter; Calloe, Kirstine; Thomsen, Morten B

    2015-08-01

    Inherited ion channelopathies and electrical remodeling in heart disease alter the cardiac action potential with important consequences for excitation-contraction coupling. Potassium channel-interacting protein 2 (KChIP2) is reduced in heart failure and interacts under physiological conditions with both Kv4 to conduct the fast-recovering transient outward K(+) current (Ito,f) and with CaV1.2 to mediate the inward L-type Ca(2+) current (ICa,L). Anesthetized KChIP2(-/-) mice have normal cardiac contraction despite the lower ICa,L, and we hypothesized that the delayed repolarization could contribute to the preservation of contractile function. Detailed analysis of current kinetics shows that only ICa,L density is reduced, and immunoblots demonstrate unaltered CaV1.2 and CaVβ₂ protein levels. Computer modeling suggests that delayed repolarization would prolong the period of Ca(2+) entry into the cell, thereby augmenting Ca(2+)-induced Ca(2+) release. Ca(2+) transients in disaggregated KChIP2(-/-) cardiomyocytes are indeed comparable to wild-type transients, corroborating the preserved contractile function and suggesting that the compensatory mechanism lies in the Ca(2+)-induced Ca(2+) release event. We next functionally probed dyad structure, ryanodine receptor Ca(2+) sensitivity, and sarcoplasmic reticulum Ca(2+) load and found that increased temporal synchronicity of the Ca(2+) release in KChIP2(-/-) cardiomyocytes may reflect improved dyad structure aiding the compensatory mechanisms in preserving cardiac contractile force. Thus the bimodal effect of KChIP2 on Ito,f and ICa,L constitutes an important regulatory effect of KChIP2 on cardiac contractility, and we conclude that delayed repolarization and improved dyad structure function together to preserve cardiac contraction in KChIP2(-/-) mice. Copyright © 2015 the American Physiological Society.

  13. A five-primary photostimulator suitable for studying intrinsically photosensitive retinal ganglion cell functions in humans

    PubMed Central

    Cao, Dingcai; Nicandro, Nathaniel; Barrionuevo, Pablo A.

    2015-01-01

    Intrinsically photosensitive retinal ganglion cells (ipRGCs) can respond to light directly through self-contained photopigment, melanopsin. IpRGCs also receive synaptic inputs from rods and cones. Thus, studying ipRGC functions requires a novel photostimulating method that can account for all of the photoreceptor inputs. Here, we introduced an inexpensive LED-based five-primary photostimulator that can control the excitations of rods, S-, M-, L-cones, and melanopsin-containing ipRGCs in humans at constant background photoreceptor excitation levels, a critical requirement for studying the adaptation behavior of ipRGCs with rod, cone, or melanopsin input. We described the theory and technical aspects (including optics, electronics, software, and calibration) of the five-primary photostimulator. Then we presented two preliminary studies using the photostimulator we have implemented to measure melanopsin-mediated pupil responses and temporal contrast sensitivity function (TCSF). The results showed that the S-cone input to pupil responses was antagonistic to the L-, M- or melanopsin inputs, consistent with an S-OFF and (L + M)-ON response property of primate ipRGCs (Dacey et al., 2005). In addition, the melanopsin-mediated TCSF had a distinctive pattern compared with L + M or S-cone mediated TCSF. Other than controlling individual photoreceptor excitation independently, the five-primary photostimulator has the flexibility in presenting stimuli modulating any combination of photoreceptor excitations, which allows researchers to study the mechanisms by which ipRGCs combine various photoreceptor inputs. PMID:25624466

  14. The Effects of Solar Wind Dynamic Pressure Changes on the Substorm Auroras and Energetic Electron Injections on 24 August 2005

    NASA Astrophysics Data System (ADS)

    Li, L. Y.; Wang, Z. Q.

    2018-01-01

    After the passage of an interplanetary (IP) shock at 06:13 UT on 24 August 2005, the enhancement (>6 nPa) of solar wind dynamic pressure and the southward turning of interplanetary magnetic field (IMF) cause the earthward movement of dayside magnetopause and the drift loss of energetic particles near geosynchronous orbit. The persistent electron drift loss makes the geosynchronous satellites cannot observe the substorm electron injection phenomenon during the two substorm expansion phases (06:57-07:39 UT) on that day. Behind the IP shock, the fluctuations ( 0.5-3 nPa) of solar wind dynamic pressure not only alter the dayside auroral brightness but also cause the entire auroral oval to swing in the day-night direction. However, there is no Pi2 pulsation in the nightside auroral oval during the substorm growth phase from 06:13 to 06:57 UT. During the subsequent two substorm expansion phases, the substorm expansion activities cause the nightside aurora oval brightening from substorm onset site to higher latitudes, and meanwhile, the enhancement (decline) of solar wind dynamic pressure makes the nightside auroral oval move toward the magnetic equator (the magnetic pole). These observations demonstrate that solar wind dynamic pressure changes and substorm expansion activities can jointly control the luminosity and location of the nightside auroral oval when the internal and external disturbances occur simultaneously. During the impact of a strong IP shock, the earthward movement of dayside magnetopause probably causes the disappearance of the substorm electron injections near geosynchronous orbit.

  15. The Integrity of FPGA Designs: Capabilities Enabled by Unlocking Bitstreams and 3rd-Party IP

    DTIC Science & Technology

    2012-03-01

    represented in an HDL such as Verilog or in another common electronic design format such as the Electronic Design Interchange Format ( EDIF ). Whether...Verilog or EDIF , however, the synthesized netlist is expressed as a connected and configured arrangement of the FPGA resources necessary to realize

  16. A Physiological and Psychometric Evaluation of Human Subconscious Visual Response and Its Application in Health Promoting Lighting

    NASA Astrophysics Data System (ADS)

    Vartanian, Garen V.

    Subconscious vision is a recent focus of the vision science community, brought on by the discovery of a previously unknown photoreceptor in the retina dedicated to driving non-image-forming responses, intrinsically photosensitive retinal ganglion cells (ipRGCs). In addition to accepting inputs from rod and cone photoreceptors, ipRGCs contain their own photopigment, melanopsin, and are considered true photoreceptors. ipRGCs drive various non-image-forming photoresponses, including circadian photoentrainment, melatonin suppression, and pupil constriction. In order to understand more about ipRGC function in humans, we studied its sensitivity to light stimuli in the evening and day. First, we measured the sensitivity threshold of melatonin suppression at night. Using a protocol that enhances data precision, we have found the threshold for human melatonin suppression to be two orders of magnitude lower than previously reported. This finding has far-reaching implications since there is mounting evidence that nocturnal activation of the circadian system can be harmful. Paradoxically, ipRGCs are understimulated during the day. Optimizing daytime non-image-forming photostimulation has health benefits, such as increased alertness, faster reaction times, better sleep quality, and treatment of depression. In order to enhance ipRGC excitation, we aimed to circumvent adaptation (i.e. desensitization) of the photoresponse by using flickering instead of steady light. We find that properly timed flickering light enhances pupillary light reflex significantly when compared to steady light with 9-fold more energy density. Employing our findings, a new form of LED light is proposed to enhance subconscious visual responses at a typical indoor illuminance level. Using the silent substitution technique, a melanopsin-selective flicker is introduced into the light. A linear optimization algorithm is used to maximize the contrast of the subconscious, melanopsin-based response function while keeping conscious, cone-driven responses to the pulsing light fixed. Additional boundary conditions utilizing test color samples as an environmental mimic are introduced to limit the amount of perceived color change in a simulated environment. Two examples of lights are given to illustrate potential applications for general illumination and therapeutic purposes. For the lighting and electronics industry, we hope our study of subconscious-stimulative thresholds at night will better inform their design guidelines for health conscious products.

  17. Human Induced Pluripotent Stem Cells Free of Vector and Transgene Sequences

    PubMed Central

    Yu, Junying; Hu, Kejin; Smuga-Otto, Kim; Tian, Shulan; Stewart, Ron; Slukvin, Igor I.; Thomson, James A.

    2009-01-01

    Reprogramming differentiated human cells to induced pluripotent stem (iPS) cells has applications in basic biology, drug development, and transplantation. Human iPS cell derivation previously required vectors that integrate into the genome, which can create mutations and limit the utility of the cells in both research and clinical applications. Here we describe the derivation of human iPS cells using non-integrating episomal vectors. After removal of the episome, iPS cells completely free of vector and transgene sequences are derived that are similar to human embryonic stem (ES) cells in proliferative and developmental potential. These results demonstrate that reprogramming human somatic cells does not require genomic integration or the continued presence of exogenous reprogramming factors, and removes one obstacle to the clinical application of human iPS cells. PMID:19325077

  18. Induced pluripotent stem cells in hematology: current and future applications

    PubMed Central

    Focosi, D; Amabile, G; Di Ruscio, A; Quaranta, P; Tenen, D G; Pistello, M

    2014-01-01

    Reprogramming somatic cells into induced pluripotent stem (iPS) cells is nowadays approaching effectiveness and clinical grade. Potential uses of this technology include predictive toxicology, drug screening, pathogenetic studies and transplantation. Here, we review the basis of current iPS cell technology and potential applications in hematology, ranging from disease modeling of congenital and acquired hemopathies to hematopoietic stem and other blood cell transplantation. PMID:24813079

  19. Host responses to interspecific brood parasitism: a by-product of adaptations to conspecific parasitism?

    PubMed Central

    2014-01-01

    Background Why have birds evolved the ability to reject eggs? Typically, foreign egg discrimination is interpreted as evidence that interspecific brood parasitism (IP) has selected for the host’s ability to recognize and eliminate foreign eggs. Fewer studies explore the alternative hypothesis that rejection of interspecific eggs is a by-product of host defenses, evolved against conspecific parasitism (CP). We performed a large scale study with replication across taxa (two congeneric Turdus thrushes), space (populations), time (breeding seasons), and treatments (three types of experimental eggs), using a consistent design of egg rejection experiments (n = 1057 nests; including controls), in areas with potential IP either present (Europe; native populations) or absent (New Zealand; introduced populations). These comparisons benefited from the known length of allopatry (one and a half centuries), with no gene flow between native and introduced populations, which is rarely available in host-parasite systems. Results Hosts rejected CP at unusually high rates for passerines (up to 60%). CP rejection rates were higher in populations with higher conspecific breeding densities and no risks of IP, supporting the CP hypothesis. IP rejection rates did not covary geographically with IP risk, contradicting the IP hypothesis. High egg rejection rates were maintained in the relatively long-term isolation from IP despite non-trivial rejection costs and errors. Conclusions These egg rejection patterns, combined with recent findings that these thrushes are currently unsuitable hosts of the obligate parasitic common cuckoo (Cuculus canorus), are in agreement with the hypothesis that the rejection of IP is a by-product of fine-tuned egg discrimination evolved due to CP. Our study highlights the importance of considering both IP and CP simultaneously as potential drivers in the evolution of egg discrimination, and illustrates how populations introduced to novel ecological contexts can provide critical insights into brood parasite-host coevolution. PMID:24834103

  20. Host responses to interspecific brood parasitism: a by-product of adaptations to conspecific parasitism?

    PubMed

    Samas, Peter; Hauber, Mark E; Cassey, Phillip; Grim, Tomas

    2014-01-01

    Why have birds evolved the ability to reject eggs? Typically, foreign egg discrimination is interpreted as evidence that interspecific brood parasitism (IP) has selected for the host's ability to recognize and eliminate foreign eggs. Fewer studies explore the alternative hypothesis that rejection of interspecific eggs is a by-product of host defenses, evolved against conspecific parasitism (CP). We performed a large scale study with replication across taxa (two congeneric Turdus thrushes), space (populations), time (breeding seasons), and treatments (three types of experimental eggs), using a consistent design of egg rejection experiments (n = 1057 nests; including controls), in areas with potential IP either present (Europe; native populations) or absent (New Zealand; introduced populations). These comparisons benefited from the known length of allopatry (one and a half centuries), with no gene flow between native and introduced populations, which is rarely available in host-parasite systems. Hosts rejected CP at unusually high rates for passerines (up to 60%). CP rejection rates were higher in populations with higher conspecific breeding densities and no risks of IP, supporting the CP hypothesis. IP rejection rates did not covary geographically with IP risk, contradicting the IP hypothesis. High egg rejection rates were maintained in the relatively long-term isolation from IP despite non-trivial rejection costs and errors. These egg rejection patterns, combined with recent findings that these thrushes are currently unsuitable hosts of the obligate parasitic common cuckoo (Cuculus canorus), are in agreement with the hypothesis that the rejection of IP is a by-product of fine-tuned egg discrimination evolved due to CP. Our study highlights the importance of considering both IP and CP simultaneously as potential drivers in the evolution of egg discrimination, and illustrates how populations introduced to novel ecological contexts can provide critical insights into brood parasite-host coevolution.

  1. A yield-optimized access to double-helical SnIP via a Sn/SnI2 approach

    NASA Astrophysics Data System (ADS)

    Utrap, André; Xiang, Ng Yan; Nilges, Tom

    2017-10-01

    Herein we report on the optimized synthesis process of SnIP, the first inorganic double helix compound which shows high mechanical flexibility, a strong tendency for cleavage or delamination and intriguing electronic properties. In this work we analyzed the influence of SnI2 as a reaction promotor or mineralizer compound for the synthesis of SnIP. In previous studies Sn/SnI4 was used as a precursor and chemical transport agent for the SnIP synthesis but significant amounts of non-reacted tin halide (SnI2 and SnI4) remained after the formation of the target compound reducing its quality and yield. Significantly less tin halide residue can be observed which suggests a reduction of side-reactions. While the Sn/SnI4 couple works perfectly for the synthesis of the two-dimensional material phosphorene precursor black phosphorus the Sn/SnI2 couple is beneficial for the one-dimensional ternary polyphosphide SnIP. These results strongly encourage the theory of SnI2 as the important reaction intermediate in the synthesis of covalently-bonded polyphosphide substructures and element allotropes at elevated temperatures.

  2. MPTP-meditated hippocampal dopamine deprivation modulates synaptic transmission and activity-dependent synaptic plasticity

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

    Zhu Guoqi; Chen Ying; Huang Yuying

    2011-08-01

    Parkinson's disease (PD)-like symptoms including learning deficits are inducible by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Therefore, it is possible that MPTP may disturb hippocampal memory processing by modulation of dopamine (DA)- and activity-dependent synaptic plasticity. We demonstrate here that intraperitoneal (i.p.) MPTP injection reduces the number of tyrosine hydroxylase (TH)-positive neurons in the substantia nigra (SN) within 7 days. Subsequently, the TH expression level in SN and hippocampus and the amount of DA and its metabolite DOPAC in striatum and hippocampus decrease. DA depletion does not alter basal synaptic transmission and changes pair-pulse facilitation (PPF) of field excitatory postsynaptic potentials (fEPSPs) only atmore » the 30 ms inter-pulse interval. In addition, the induction of long-term potentiation (LTP) is impaired whereas the duration of long-term depression (LTD) becomes prolonged. Since both LTP and LTD depend critically on activation of NMDA and DA receptors, we also tested the effect of DA depletion on NMDA receptor-mediated synaptic transmission. Seven days after MPTP injection, the NMDA receptor-mediated fEPSPs are decreased by about 23%. Blocking the NMDA receptor-mediated fEPSP does not mimic the MPTP-LTP. Only co-application of D1/D5 and NMDA receptor antagonists during tetanization resembled the time course of fEPSP potentiation as observed 7 days after i.p. MPTP injection. Together, our data demonstrate that MPTP-induced degeneration of DA neurons and the subsequent hippocampal DA depletion alter NMDA receptor-mediated synaptic transmission and activity-dependent synaptic plasticity. - Highlights: > I.p. MPTP-injection mediates death of dopaminergic neurons. > I.p. MPTP-injection depletes DA and DOPAC in striatum and hippocampus. > I.p. MPTP-injection does not alter basal synaptic transmission. > Reduction of LTP and enhancement of LTD after i.p. MPTP-injection. > Attenuation of NMDA-receptors mediated fEPSPs after i.p. MPTP-injection.« less

  3. Prognostic value of CtIP/RBBP8 expression in breast cancer.

    PubMed

    Soria-Bretones, Isabel; Sáez, Carmen; Ruíz-Borrego, Manuel; Japón, Miguel A; Huertas, Pablo

    2013-12-01

    CtIP/RBBP8 is a multifunctional protein involved in transcription, DNA replication, DNA repair by homologous recombination and the G1 and G2 checkpoints. Its multiple roles are controlled by its interaction with several specific factors, including the tumor suppressor proteins BRCA1 and retinoblastoma. Both its functions and interactors point to a putative oncogenic potential of CtIP/RBBP8 loss. However, CtIP/RBBP8 relevance in breast tumor appearance, development, and prognosis has yet to be established. We performed a retrospective analysis of CtIP/RBBP8 and RB1 levels by immunohistochemistry using 384 paraffin-embedded breast cancer biopsies obtained during tumor removal surgery. We have observed that low or no expression of CtIP/RBBP8 correlates with high-grade breast cancer and with nodal metastasis. Reduction on CtIP/RBBP8 is most common in hormone receptor (HR)-negative, HER2-positive, and basal-like tumors. We observed lower levels of RB1 on those tumors with reduced CtIP/RBBP8 levels. On luminal tumors, decreased but not absence of CtIP/RBBP8 levels correlate with increased disease-free survival when treated with a combination of hormone, radio, and chemo therapies. © 2013 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  4. Spectroscopic and density functional theory studies of 5,7,3',5'-tetrahydroxyflavanone from the leaves of Olea ferruginea.

    PubMed

    Hashmi, Muhammad Ali; Khan, Afsar; Ayub, Khurshid; Farooq, Umar

    2014-07-15

    5,7,3',5'-Tetrahydroxyflavanone (1) was isolated from the leaves of Olea ferruginea and a theoretical model was developed for obtaining the electronic and spectroscopic properties of 1. The geometric and electronic properties were calculated at B3LYP/6-311 G (d, p) level of Density Functional Theory (DFT). The theoretical data was in good agreement with the experimental one. The optimized geometric parameters of compound 1 were calculated for the first time. The theoretical vibrational frequencies of 1 were found to correlate with the experimental IR spectrum after a scaling factor of 0.9811. The UV and NMR spectral data computed theoretically were in good agreement with the experimental data. Electronic properties of the compound i.e., ionization potential (IP), electron affinity (EA), coefficients of HOMO and LUMO were estimated computationally for the first time which can be used to explain its antioxidant as well as other related activities and more active sites on it. The intermolecular interactions and their effects on IR frequencies, electronic and geometric parameters were simulated using water molecule as a model for hydrogen bonding with flavonoid hydroxyl groups. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Spectroscopic and density functional theory studies of 5,7,3‧,5‧-tetrahydroxyflavanone from the leaves of Olea ferruginea

    NASA Astrophysics Data System (ADS)

    Hashmi, Muhammad Ali; Khan, Afsar; Ayub, Khurshid; Farooq, Umar

    2014-07-01

    5,7,3‧,5‧-Tetrahydroxyflavanone (1) was isolated from the leaves of Olea ferruginea and a theoretical model was developed for obtaining the electronic and spectroscopic properties of 1. The geometric and electronic properties were calculated at B3LYP/6-311 G (d, p) level of Density Functional Theory (DFT). The theoretical data was in good agreement with the experimental one. The optimized geometric parameters of compound 1 were calculated for the first time. The theoretical vibrational frequencies of 1 were found to correlate with the experimental IR spectrum after a scaling factor of 0.9811. The UV and NMR spectral data computed theoretically were in good agreement with the experimental data. Electronic properties of the compound i.e., ionization potential (IP), electron affinity (EA), coefficients of HOMO and LUMO were estimated computationally for the first time which can be used to explain its antioxidant as well as other related activities and more active sites on it. The intermolecular interactions and their effects on IR frequencies, electronic and geometric parameters were simulated using water molecule as a model for hydrogen bonding with flavonoid hydroxyl groups.

  6. Evidences for the agmatine involvement in antidepressant like effect of bupropion in mouse forced swim test.

    PubMed

    Kotagale, Nandkishor R; Tripathi, Sunil J; Aglawe, Manish M; Chopde, Chandrabhan T; Umekar, Milind J; Taksande, Brijesh G

    2013-06-01

    Although bupropion has been widely used in the treatment of depression, the precise mechanism of its therapeutic actions is not fully understood. The present study investigated the role of agmatine in an antidepressant like effect of bupropion in mouse forced swim test. The antidepressant like effect of bupropion was potentiated by pretreatment with agmatine (10-20mg/kg, ip) and by the drugs known to increase endogenous agmatine levels in brain viz., l-arginine (40 μg/mouse, icv), an agmatine biosynthetic precursor, ornithine decarboxylase inhibitor, dl-α-difluoromethyl ornithine hydrochloride, DFMO (12.5 μg/mouse, icv), diamine oxidase inhibitor, aminoguanidine (6.5 μg/mouse, icv) and agmatinase inhibitor, arcaine (50 μg/mouse, icv) as well as imidazoline I1 receptor agonists, moxonidine (0.25mg/kg, ip) and clonidine (0.015 mg/kg, ip) and imidazoline I2 receptor agonist, 2-(2-benzofuranyl)-2-imidazoline hydrochloride, 2-BFI (5mg/kg, ip). Conversely, prior administration of I1 receptor antagonist, efaroxan (1mg/kg, ip) and I2 receptor antagonist, idazoxan (0.25mg/kg, ip) blocked the antidepressant like effect of bupropion and its synergistic combination with agmatine. These results demonstrate involvement of agmatine in the antidepressant like effect of bupropion and suggest agmatine and imidazoline receptors as a potential therapeutic target for the treatment of depressive disorders. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. ChIP-chip.

    PubMed

    Kim, Tae Hoon; Dekker, Job

    2018-05-01

    ChIP-chip can be used to analyze protein-DNA interactions in a region-wide and genome-wide manner. DNA microarrays contain PCR products or oligonucleotide probes that are designed to represent genomic sequences. Identification of genomic sites that interact with a specific protein is based on competitive hybridization of the ChIP-enriched DNA and the input DNA to DNA microarrays. The ChIP-chip protocol can be divided into two main sections: Amplification of ChIP DNA and hybridization of ChIP DNA to arrays. A large amount of DNA is required to hybridize to DNA arrays, and hybridization to a set of multiple commercial arrays that represent the entire human genome requires two rounds of PCR amplifications. The relative hybridization intensity of ChIP DNA and that of the input DNA is used to determine whether the probe sequence is a potential site of protein-DNA interaction. Resolution of actual genomic sites bound by the protein is dependent on the size of the chromatin and on the genomic distance between the probes on the array. As with expression profiling using gene chips, ChIP-chip experiments require multiple replicates for reliable statistical measure of protein-DNA interactions. © 2018 Cold Spring Harbor Laboratory Press.

  8. Benchmarking the Fundamental Electronic Properties of small TiO 2 Nanoclusters by GW and Coupled Cluster Theory Calculations

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

    Berardo, Enrico; Kaplan, Ferdinand; Bhaskaran-Nair, Kiran

    We study the vertical ionisation potential, electron affinity, fundamental gap and exciton binding energy values of small bare and hydroxylated TiO 2 nanoclusters to understand how the excited state properties change as a function of size and hydroxylation. In addition, we have employed a range of many-body methods; including G 0 W 0, qs GW, EA/IP-EOM-CCSD and DFT (B3LYP, PBE), to compare the performance and predictions of the different classes of methods. We demonstrate that for bare (i.e. non-hydroxylated) clusters all many-body methods predict the same trend with cluster size. The highest occupied and lowest unoccupied DFT orbitals follow themore » same trends as the electron affinity and ionisation potentials predicted by the many-body methods but are generally far too shallow and deep respectively in absolute terms. In contrast, the ΔDFT method is found to yield values in the correct energy window. However, its predictions depend on the functional used and do not necessarily follow trends based on the many-body methods. The effect of hydroxylation of the clusters is to open up both the optical and fundamental gap. In conclusion, a simple microscopic explanation for the observed trends with cluster size and upon hydroxylation is proposed in terms of the Madelung onsite potential.« less

  9. Benchmarking the Fundamental Electronic Properties of small TiO 2 Nanoclusters by GW and Coupled Cluster Theory Calculations

    DOE PAGES

    Berardo, Enrico; Kaplan, Ferdinand; Bhaskaran-Nair, Kiran; ...

    2017-06-19

    We study the vertical ionisation potential, electron affinity, fundamental gap and exciton binding energy values of small bare and hydroxylated TiO 2 nanoclusters to understand how the excited state properties change as a function of size and hydroxylation. In addition, we have employed a range of many-body methods; including G 0 W 0, qs GW, EA/IP-EOM-CCSD and DFT (B3LYP, PBE), to compare the performance and predictions of the different classes of methods. We demonstrate that for bare (i.e. non-hydroxylated) clusters all many-body methods predict the same trend with cluster size. The highest occupied and lowest unoccupied DFT orbitals follow themore » same trends as the electron affinity and ionisation potentials predicted by the many-body methods but are generally far too shallow and deep respectively in absolute terms. In contrast, the ΔDFT method is found to yield values in the correct energy window. However, its predictions depend on the functional used and do not necessarily follow trends based on the many-body methods. The effect of hydroxylation of the clusters is to open up both the optical and fundamental gap. In conclusion, a simple microscopic explanation for the observed trends with cluster size and upon hydroxylation is proposed in terms of the Madelung onsite potential.« less

  10. Hippocampal A-type current and Kv4.2 channel modulation by the sulfonylurea compound NS5806.

    PubMed

    Witzel, Katrin; Fischer, Paul; Bähring, Robert

    2012-12-01

    We examined the effects of the sulfonylurea compound NS5806 on neuronal A-type channel function. Using whole-cell patch-clamp we studied the effects of NS5806 on the somatodendritic A-type current (I(SA)) in cultured hippocampal neurons and the currents mediated by Kv4.2 channels coexpressed with different auxiliary β-subunits, including both Kv channel interacting proteins (KChIPs) and dipeptidyl aminopeptidase-related proteins (DPPs), in HEK 293 cells. The amplitude of the I(SA) component in hippocampal neurons was reduced in the presence of 20 μM NS5806. I(SA) decay kinetics were slowed and the recovery kinetics accelerated, but the voltage dependence of steady-state inactivation was shifted to more negative potentials by NS5806. The peak amplitudes of currents mediated by ternary Kv4.2 channel complexes, associated with DPP6-S (short splice-variant) and either KChIP2, KChIP3 or KChIP4, were potentiated and their macroscopic inactivation slowed by NS5806, whereas the currents mediated by binary Kv4.2 channels, associated only with DPP6-S, were suppressed, and the NS5806-mediated slowing of macroscopic inactivation was less pronounced. Neither potentiation nor suppression and no effect on current decay kinetics in the presence of NS5806 were observed for Kv4.2 channels associated with KChIP3 and the N-type inactivation-conferring DPP6a splice-variant. For all recombinant channel complexes, NS5806 slowed the recovery from inactivation and shifted the voltage dependence of steady-state inactivation to more negative potentials. Our results demonstrate the activity of NS5806 on native I(SA) and possible molecular correlates in the form of recombinant Kv4.2 channels complexed with different KChIPs and DPPs, and they shed some light on the mechanism of NS5806 action. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Representation of Semantic Similarity in the Left Intraparietal Sulcus: Functional Magnetic Resonance Imaging Evidence

    PubMed Central

    Neyens, Veerle; Bruffaerts, Rose; Liuzzi, Antonietta G.; Kalfas, Ioannis; Peeters, Ronald; Keuleers, Emmanuel; Vogels, Rufin; De Deyne, Simon; Storms, Gert; Dupont, Patrick; Vandenberghe, Rik

    2017-01-01

    According to a recent study, semantic similarity between concrete entities correlates with the similarity of activity patterns in left middle IPS during category naming. We examined the replicability of this effect under passive viewing conditions, the potential role of visuoperceptual similarity, where the effect is situated compared to regions that have been previously implicated in visuospatial attention, and how it compares to effects of object identity and location. Forty-six subjects participated. Subjects passively viewed pictures from two categories, musical instruments and vehicles. Semantic similarity between entities was estimated based on a concept-feature matrix obtained in more than 1,000 subjects. Visuoperceptual similarity was modeled based on the HMAX model, the AlexNet deep convolutional learning model, and thirdly, based on subjective visuoperceptual similarity ratings. Among the IPS regions examined, only left middle IPS showed a semantic similarity effect. The effect was significant in hIP1, hIP2, and hIP3. Visuoperceptual similarity did not correlate with similarity of activity patterns in left middle IPS. The semantic similarity effect in left middle IPS was significantly stronger than in the right middle IPS and also stronger than in the left or right posterior IPS. The semantic similarity effect was similar to that seen in the angular gyrus. Object identity effects were much more widespread across nearly all parietal areas examined. Location effects were relatively specific for posterior IPS and area 7 bilaterally. To conclude, the current findings replicate the semantic similarity effect in left middle IPS under passive viewing conditions, and demonstrate its anatomical specificity within a cytoarchitectonic reference frame. We propose that the semantic similarity effect in left middle IPS reflects the transient uploading of semantic representations in working memory. PMID:28824405

  12. Avoidance of accelerated aging in schizophrenia?: Clinical and biological characterization of an exceptionally high functioning individual.

    PubMed

    Palmer, Barton W; Moore, Raeanne C; Eyler, Lisa T; Pinto, Luz L; Saks, Elyn R; Jeste, Dilip V

    2018-06-01

    To determine the clinical and biological characteristics of an exceptionally high functioning index person (IP) with schizophrenia in her mid-50s, which may represent compensatory mechanisms, and potentially, avoidance of the accelerated aging typically associated with schizophrenia. IP, 11 other women with schizophrenia, and 11 non-psychiatric comparison (NC) women were assessed with standard ratings of psychopathology, neurocognitive function, decisional capacity, and functional brain imaging. IP was also compared to a sample of demographically similar NCs (N=45) and persons with schizophrenia (N=42) on a set of blood-based biomarkers of aging related to metabolic function, oxidative stress, and inflammation. IP's scores on working memory, and levels of brain activation during an affective face matching task in the left fusiform, right lingual, and left precentral gyri, exceeded NCs. IP was similar to NCs in severity of negative symptoms, most neurocognitive functions, decisional capacity, and brain activation in the left inferior occipital gyrus during a selective stopping task. IP's levels on 11 of 14 metabolic and inflammatory biomarkers of aging were better than NCs and the schizophrenia group. Although speculative, results suggest a possible model in which superior working memory permits a person to be aware of the potentially psychotic nature of a thought or perception, and adjust response accordingly. Compensatory overactivity of brain regions during affective processing may also reflect heightened meta-awareness in emotional situations. Biomarker levels raise the possibility that IP partially avoided the accelerated biological aging associated with schizophrenia. Published by Elsevier B.V.

  13. Low-Frequency Radio Bursts and Space Weather

    NASA Technical Reports Server (NTRS)

    Gopalswamy, N.

    2016-01-01

    Low-frequency radio phenomena are due to the presence of nonthermal electrons in the interplanetary (IP) medium. Understanding these phenomena is important in characterizing the space environment near Earth and other destinations in the solar system. Substantial progress has been made in the past two decades, because of the continuous and uniform data sets available from space-based radio and white-light instrumentation. This paper highlights some recent results obtained on IP radio phenomena. In particular, the source of type IV radio bursts, the behavior of type III storms, shock propagation in the IP medium, and the solar-cycle variation of type II radio bursts are considered. All these phenomena are closely related to solar eruptions and active region evolution. The results presented were obtained by combining data from the Wind and SOHO missions.

  14. Superconductivity in metal coated graphene

    NASA Astrophysics Data System (ADS)

    Uchoa, Bruno; Castro Neto, Antonio

    2007-03-01

    Graphene, a single atomic layer of graphite, is a two dimensional (2D) zero gap insulator with a high electronic mobility between nearest neighbor carbon sites. The unique electronic properties of graphene, from the semi-metallic behavior to the observation of an anomalous quantum Hall effect and a zero field quantized minimum of conductivity derive from the relativistic nature of its quasiparticles. By doping graphene, it behaves in several aspects as a conventional Fermi liquid, where electrons may form Cooper pairs by coupling with a bosonic mode. In this talk, we develop a mean-field phenomenology of superconductivity in a honeycomb lattice. We predict the possibility of two distinct phases, a singlet s-wave phase and a novel p+ip wave phase in the singlet channel. At half filling, the p+ip phase is gapless and superconductivity is a hidden order. We propose a few possible sources of Cooper pairing instability in graphene coated with alkaline and transition metals, and similar low dimensional graphene based devices.

  15. Acetylcholine attenuated TNF-α-induced intracellular Ca2+ overload by inhibiting the formation of the NCX1-TRPC3-IP3R1 complex in human umbilical vein endothelial cells.

    PubMed

    Zhao, Ming; Jia, Hang-Huan; Liu, Long-Zhu; Bi, Xue-Yuan; Xu, Man; Yu, Xiao-Jiang; He, Xi; Zang, Wei-Jin

    2017-06-01

    The endoplasmic reticulum (ER) forms discrete junctions with the plasma membrane (PM) that play a critical role in the regulation of Ca 2+ signaling during cellular bioenergetics, apoptosis and autophagy. We have previously confirmed that acetylcholine can inhibit ER stress and apoptosis after inflammatory injury. However, limited research has focused on the effects of acetylcholine on ER-PM junctions. In this work, we evaluated the structure and function of the supramolecular sodium-calcium exchanger 1 (NCX1)-transient receptor potential canonical 3 (TRPC3)-inositol 1,4,5-trisphosphate receptor 1 (IP3R1) complex, which is involved in regulating Ca 2+ homeostasis during inflammatory injury. The width of the ER-PM junctions of human umbilical vein endothelial cells (HUVECs) was measured in nanometres using transmission electron microscopy and a fluorescent probe for Ca 2+ . Protein-protein interactions were assessed by immunoprecipitation. Ca 2+ concentration was measured using a confocal microscope. An siRNA assay was employed to silence specific proteins. Our results demonstrated that the peripheral ER was translocated to PM junction sites when induced by tumour necrosis factor-alpha (TNF-α) and that NCX1-TRPC3-IP3R1 complexes formed at these sites. After down-regulating the protein expression of NCX1 or IP3R1, we found that the NCX1-mediated inflow of Ca 2+ and the release of intracellular Ca 2+ stores were reduced in TNF-α-treated cells. We also observed that acetylcholine attenuated the formation of NCX1-TRPC3-IP3R1 complexes and maintained calcium homeostasis in cells treated with TNF-α. Interestingly, the positive effects of acetylcholine were abolished by the selective M3AChR antagonist darifenacin and by AMPK siRNAs. These results indicate that acetylcholine protects endothelial cells from TNF-alpha-induced injury, [Ca 2+ ] cyt overload and ER-PM interactions, which depend on the muscarinic 3 receptor/AMPK pathway, and that acetylcholine may be a new inhibitor for suppressing [Ca 2+ ] cyt overload. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Equation-of-motion coupled-cluster method for ionised states with spin-orbit coupling using open-shell reference wavefunction

    NASA Astrophysics Data System (ADS)

    Wang, Zhifan; Wang, Fan

    2018-04-01

    The equation-of-motion coupled-cluster method for ionised states at the singles and doubles level (EOM-IP-CCSD) with spin-orbit coupling (SOC) included in post-Hartree-Fock (HF) steps is extended to spatially non-degenerate open-shell systems such as high spin states of s1, p3, σ1 or π2 configuration in this work. Pseudopotentials are employed to treat relativistic effects and spin-unrestricted scalar relativistic HF determinant is adopted as reference in calculations. Symmetry is not exploited in the implementation since both time-reversal and spatial symmetry is broken due to SOC. IPs with the EOM-IP-CCSD approach are those from the 3Σ1- states for high spin state of π2 configuration, while the ground state is the 3Σ0- state. When removing an electron from the high spin state of p3 configuration, only the 3P2 state can be reached. The open-shell EOM-IP-CCSD approach with SOC was employed in calculating IPs of some open-shell atoms with s1 configuration, diatomic molecules with π2 configuration and SOC splitting of the ionised π1 state, as well as IPs of VA atoms with p3 configuration. Our results demonstrate that this approach can be applied to ionised states of spatially non-degenerate open-shell states containing heavy elements with reasonable accuracy.

  17. An Elevation in Physical Coupling of Type 1 IP3 Receptors to TRPC3 Channels Constricts Mesenteric Arteries in Genetic Hypertension

    PubMed Central

    Adebiyi, Adebowale; Thomas-Gatewood, Candice M.; Leo, M. Dennis; Kidd, Michael W.; Neeb, Zachary P.; Jaggar, Jonathan H.

    2013-01-01

    Hypertension is associated with an elevation in agonist-induced vasoconstriction, but mechanisms involved require further investigation. Many vasoconstrictors bind to phospholipase C-coupled receptors, leading to an elevation in inositol 1,4,5-trisphosphate (IP3) that activates sarcoplasmic reticulum (SR) IP3 receptors (IP3Rs). In cerebral artery myocytes, IP3Rs release SR Ca2+ and can physically couple to canonical transient receptor potential 3 (TRPC3) channels in a caveolin-1-containing macromolecular complex, leading to cation current (ICat) activation that stimulates vasoconstriction. Here, we investigated mechanisms by which IP3Rs control vascular contractility in systemic arteries and IP3R involvement in elevated agonist-induced vasoconstriction during hypertension. Total and plasma membrane-localized TRPC3 protein was ~2.7- and 2-fold higher in mesenteric arteries of hypertensive spontaneously hypertensive rats (SHR) than in Wistar-Kyoto (WKY) rat controls, respectively. In contrast, IP3R1, TRPC1, TRPC6, and caveolin-1 expression was similar. TRPC3 expression was also similar in arteries of pre-hypertensive SHR and WKY rats. Control, IP3- and endothelin-1 (ET-1)-induced FRET between IP3R1 and TRPC3 was higher in hypertensive SHR than WKY myocytes. IP3-induced ICat was ~3-fold larger in SHR myocytes. Pyr3, a selective TRPC3 channel blocker, and CIRBP-TAT, an IP3R-TRP physical coupling inhibitor, reduced IP3-induced ICat and ET-1-induced vasoconstriction more in SHR than WKY myocytes and arteries. Thapsigargin, a SR Ca2+-ATPase blocker, did not alter ET-1-stimulated vasoconstriction in SHR or WKY arteries. These data indicate that ET-1 stimulates physical coupling of IP3R1 to TRPC3 channels in mesenteric artery myocytes, leading to vasoconstriction. Furthermore, an elevation in IP3R1 to TRPC3 channel molecular coupling augments ET-1-induced vasoconstriction during hypertension. PMID:23045459

  18. Induced pluripotent stem (iPS) cells: a new source for cell-based therapeutics?

    PubMed

    de Lázaro, Irene; Yilmazer, Açelya; Kostarelos, Kostas

    2014-07-10

    The generation of induced pluripotent stem (iPS) cells from somatic cells by the ectopic expression of defined transcription factors has provided the regenerative medicine field with a new tool for cell replacement strategies. The advantages that these pluripotent cells can offer in comparison to other sources of stem cells include the generation of patient-derived cells and the lack of embryonic tissue while maintaining a versatile differentiation potential. The promise of iPS cell derivatives for therapeutic applications is encouraging albeit very early in development, with the first clinical study currently ongoing in Japan. Many challenges are yet to be circumvented before this technology can be clinically translated widely though. The delivery and expression of the reprogramming factors, the genomic instability, epigenetic memory and impact of cell propagation in culture are only some of the concerns. This article aims to critically discuss the potential of iPS cells as a new source of cell therapeutics. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Biosphere Reserve for All: Potentials for Involving Underrepresented Age Groups in the Development of a Biosphere Reserve through Intergenerational Practice.

    PubMed

    Mitrofanenko, Tamara; Snajdr, Julia; Muhar, Andreas; Penker, Marianne; Schauppenlehner-Kloyber, Elisabeth

    2018-05-22

    Stakeholder participation is of high importance in UNESCO biosphere reserves as model regions for sustainable development; however, certain groups remain underrepresented. The paper proposes Intergenerational Practice (IP) as a means of involving youth and elderly women and explores its options and barriers, using the example of the Salzburger Lungau and Kärntner Nockberge Biosphere Reserve in Austria. Case study analysis is used involving mixed methods. The results reveal obstacles and motivations to participating in biosphere reserve implementation and intergenerational activities for the youth and the elderly women and imply that much potential for IP exists in the biosphere reserve region. The authors propose suitable solutions from the intergenerational field to overcome identified participation obstacles and suggest benefits of incorporating IP as a management tool into biosphere reserve activities. Suggestions for future research include evaluating applications of IP in the context of protected areas, testing of methods used in other contexts, and contribution to theory development.

  20. Antiepileptic drugs and brain maturation: fetal exposure to lamotrigine generates cortical malformations in rats.

    PubMed

    Manent, Jean-Bernard; Jorquera, Isabel; Franco, Valentina; Ben-Ari, Yehezkel; Perucca, Emilio; Represa, Alfonso

    2008-02-01

    Intake of antiepileptic drugs (AEDs) during pregnancy can provoke severe and subtle fetal malformations associated with deleterious sequelae, reflecting the need for experimental investigations on the comparative teratogenic potential of these agents. We recently reported that prenatal exposure to vigabatrin and valproate, two AEDs which act through GABAergic mechanisms, induces hippocampal and cortical dysplasias in rodents. We have now investigated the effects of phenobarbital (PB, 30 mg/kg day) i.p.), a drug also endowed with GABAergic effects, and the new generation AEDs lamotrigine (LTG, 5-20mg/kg/day i.p.), topiramate (TPM, 10mg/kg/day i.p.), and levetiracetam (LEV, 50mg/kg/day i.p.) on brain development. Prenatal exposure to LTG induced hippocampal and cortical malformations in a dose-dependent manner, at maternal plasma concentrations within the clinically occurring range. These abnormalities were not observed after exposure to PB, TP and LEV. These observations raise concerns about potential clinical correlates and call for detailed comparative investigations on the consequences of AED use during pregnancy.

  1. Functional myogenic engraftment from mouse iPS cells.

    PubMed

    Darabi, Radbod; Pan, Weihong; Bosnakovski, Darko; Baik, June; Kyba, Michael; Perlingeiro, Rita C R

    2011-11-01

    Direct reprogramming of adult fibroblasts to a pluripotent state has opened new possibilities for the generation of patient- and disease-specific stem cells. However the ability of induced pluripotent stem (iPS) cells to generate tissue that mediates functional repair has been demonstrated in very few animal models of disease to date. Here we present the proof of principle that iPS cells may be used effectively for the treatment of muscle disorders. We combine the generation of iPS cells with conditional expression of Pax7, a robust approach to derive myogenic progenitors. Transplantation of Pax7-induced iPS-derived myogenic progenitors into dystrophic mice results in extensive engraftment, which is accompanied by improved contractility of treated muscles. These findings demonstrate the myogenic regenerative potential of iPS cells and provide rationale for their future therapeutic application for muscular dystrophies.

  2. Internet Protocol-Hybrid Opto-Electronic Ring Network (IP-HORNET): A Novel Internet Protocol-Over-Wavelength Division Multiplexing (IP-Over-WDM) Multiple-Access Metropolitan Area Network (MAN)

    DTIC Science & Technology

    2003-04-01

    usage times. End users may range from today’s typical users, such as home and business users, to futuristic users such as automobiles , appliances, hand...has the ability to drop a reprogrammable quantity of wavelengths into the node. The second technological requirement is a protocol that automatically...goal of the R-OADM is to have the ability to drop a reprogrammable number of wavelengths. If it is determined that at peak usage the node must receive M

  3. Cefminox, a Dual Agonist of Prostacyclin Receptor and Peroxisome Proliferator-Activated Receptor-Gamma Identified by Virtual Screening, Has Therapeutic Efficacy against Hypoxia-Induced Pulmonary Hypertension in Rats

    PubMed Central

    Xia, Jingwen; Yang, Li; Dong, Liang; Niu, Mengjie; Zhang, Shengli; Yang, Zhiwei; Wumaier, Gulinuer; Li, Ying; Wei, Xiaomin; Gong, Yi; Zhu, Ning; Li, Shengqing

    2018-01-01

    Prostacyclin receptor (IP) and peroxisome proliferator-activated receptor-gamma (PPARγ) are both potential targets for treatment of pulmonary arterial hypertension (PAH). Expression of IP and PPARγ decreases in PAH, suggesting that screening of dual agonists of IP and PPARγ might be an efficient method for drug discovery. Virtual screening (VS) of potential IP–PPARγ dual-targeting agonists was performed in the ZINC database. Ten of the identified compounds were further screened, and cefminox was found to dramatically inhibit growth of PASMCs with no obvious cytotoxicity. Growth inhibition by cefminox was partially reversed by both the IP antagonist RO113842 and the PPARγ antagonist GW9662. Investigation of the underlying mechanisms of action demonstrated that cefminox inhibits the protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway through up-regulation of the expression of phosphatase and tensin homolog (PTEN, which is inhibited by GW9662), and enhances cyclic adenosine monophosphate (cAMP) production in PASMCs (which is inhibited by RO113842). In a rat model of hypoxia-induced pulmonary hypertension, cefminox displayed therapeutic efficacy not inferior to that of the prostacyclin analog iloprost or the PPARγ agonist rosiglitazone. Our results identified cefminox as a dual agonist of IP and PPARγ that significantly inhibits PASMC proliferation by up-regulation of PTEN and cAMP, suggesting that it has potential for treatment of PAH. PMID:29527168

  4. Correlation consistent basis sets for actinides. II. The atoms Ac and Np-Lr

    NASA Astrophysics Data System (ADS)

    Feng, Rulin; Peterson, Kirk A.

    2017-08-01

    New correlation consistent basis sets optimized using the all-electron third-order Douglas-Kroll-Hess (DKH3) scalar relativistic Hamiltonian are reported for the actinide elements Ac and Np through Lr. These complete the series of sets reported previously for Th-U [K. A. Peterson, J. Chem. Phys. 142, 074105 (2015); M. Vasiliu et al., J. Phys. Chem. A 119, 11422 (2015)]. The new sets range in size from double- to quadruple-zeta and encompass both those optimized for valence (6s6p5f7s6d) and outer-core electron correlations (valence + 5s5p5d). The final sets have been contracted for both the DKH3 and eXact 2-component (X2C) Hamiltonians, yielding cc-pVnZ-DK3/cc-pVnZ-X2C sets for valence correlation and cc-pwCVnZ-DK3/cc-pwCVnZ-X2C sets for outer-core correlation (n = D, T, Q in each case). In order to test the effectiveness of the new basis sets, both atomic and molecular benchmark calculations have been carried out. In the first case, the first three atomic ionization potentials (IPs) of all the actinide elements Ac-Lr have been calculated using the Feller-Peterson-Dixon (FPD) composite approach, primarily with the multireference configuration interaction (MRCI) method. Excellent convergence towards the respective complete basis set (CBS) limits is achieved with the new sets, leading to good agreement with experiment, where these exist, after accurately accounting for spin-orbit effects using the 4-component Dirac-Hartree-Fock method. For a molecular test, the IP and atomization energy (AE) of PuO2 have been calculated also using the FPD method but using a coupled cluster approach with spin-orbit coupling accounted for using the 4-component MRCI. The present calculations yield an IP0 for PuO2 of 159.8 kcal/mol, which is in excellent agreement with the experimental electron transfer bracketing value of 162 ± 3 kcal/mol. Likewise, the calculated 0 K AE of 305.6 kcal/mol is in very good agreement with the currently accepted experimental value of 303.1 ± 5 kcal/mol. The ground state of PuO2 is predicted to be the 0 g +5Σ state.

  5. Correlation consistent basis sets for actinides. II. The atoms Ac and Np-Lr.

    PubMed

    Feng, Rulin; Peterson, Kirk A

    2017-08-28

    New correlation consistent basis sets optimized using the all-electron third-order Douglas-Kroll-Hess (DKH3) scalar relativistic Hamiltonian are reported for the actinide elements Ac and Np through Lr. These complete the series of sets reported previously for Th-U [K. A. Peterson, J. Chem. Phys. 142, 074105 (2015); M. Vasiliu et al., J. Phys. Chem. A 119, 11422 (2015)]. The new sets range in size from double- to quadruple-zeta and encompass both those optimized for valence (6s6p5f7s6d) and outer-core electron correlations (valence + 5s5p5d). The final sets have been contracted for both the DKH3 and eXact 2-component (X2C) Hamiltonians, yielding cc-pVnZ-DK3/cc-pVnZ-X2C sets for valence correlation and cc-pwCVnZ-DK3/cc-pwCVnZ-X2C sets for outer-core correlation (n = D, T, Q in each case). In order to test the effectiveness of the new basis sets, both atomic and molecular benchmark calculations have been carried out. In the first case, the first three atomic ionization potentials (IPs) of all the actinide elements Ac-Lr have been calculated using the Feller-Peterson-Dixon (FPD) composite approach, primarily with the multireference configuration interaction (MRCI) method. Excellent convergence towards the respective complete basis set (CBS) limits is achieved with the new sets, leading to good agreement with experiment, where these exist, after accurately accounting for spin-orbit effects using the 4-component Dirac-Hartree-Fock method. For a molecular test, the IP and atomization energy (AE) of PuO 2 have been calculated also using the FPD method but using a coupled cluster approach with spin-orbit coupling accounted for using the 4-component MRCI. The present calculations yield an IP 0 for PuO 2 of 159.8 kcal/mol, which is in excellent agreement with the experimental electron transfer bracketing value of 162 ± 3 kcal/mol. Likewise, the calculated 0 K AE of 305.6 kcal/mol is in very good agreement with the currently accepted experimental value of 303.1 ± 5 kcal/mol. The ground state of PuO 2 is predicted to be the Σ0g+5 state.

  6. Ataxia-telangiectasia mutated (ATM) deficiency decreases reprogramming efficiency and leads to genomic instability in iPS cells

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

    Kinoshita, Taisuke; Nagamatsu, Go, E-mail: gonag@sc.itc.keio.ac.jp; Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012

    2011-04-08

    Highlights: {yields} iPS cells were induced with a fluorescence monitoring system. {yields} ATM-deficient tail-tip fibroblasts exhibited quite a low reprogramming efficiency. {yields} iPS cells obtained from ATM-deficient cells had pluripotent cell characteristics. {yields} ATM-deficient iPS cells had abnormal chromosomes, which were accumulated in culture. -- Abstract: During cell division, one of the major features of somatic cell reprogramming by defined factors, cells are potentially exposed to DNA damage. Inactivation of the tumor suppressor gene p53 raised reprogramming efficiency but resulted in an increased number of abnormal chromosomes in established iPS cells. Ataxia-telangiectasia mutated (ATM), which is critical in the cellularmore » response to DNA double-strand breaks, may also play an important role during reprogramming. To clarify the function of ATM in somatic cell reprogramming, we investigated reprogramming in ATM-deficient (ATM-KO) tail-tip fibroblasts (TTFs). Although reprogramming efficiency was greatly reduced in ATM-KO TTFs, ATM-KO iPS cells were successfully generated and showed the same proliferation activity as WT iPS cells. ATM-KO iPS cells had a gene expression profile similar to ES cells and WT iPS cells, and had the capacity to differentiate into all three germ layers. On the other hand, ATM-KO iPS cells accumulated abnormal genome structures upon continuous passages. Even with the abnormal karyotype, ATM-KO iPS cells retained pluripotent cell characteristics for at least 20 passages. These data indicate that ATM does participate in the reprogramming process, although its role is not essential.« less

  7. Optimal use of tandem biotin and V5 tags in ChIP assays

    PubMed Central

    Kolodziej, Katarzyna E; Pourfarzad, Farzin; de Boer, Ernie; Krpic, Sanja; Grosveld, Frank; Strouboulis, John

    2009-01-01

    Background Chromatin immunoprecipitation (ChIP) assays coupled to genome arrays (Chip-on-chip) or massive parallel sequencing (ChIP-seq) lead to the genome wide identification of binding sites of chromatin associated proteins. However, the highly variable quality of antibodies and the availability of epitopes in crosslinked chromatin can compromise genomic ChIP outcomes. Epitope tags have often been used as more reliable alternatives. In addition, we have employed protein in vivo biotinylation tagging as a very high affinity alternative to antibodies. In this paper we describe the optimization of biotinylation tagging for ChIP and its coupling to a known epitope tag in providing a reliable and efficient alternative to antibodies. Results Using the biotin tagged erythroid transcription factor GATA-1 as example, we describe several optimization steps for the application of the high affinity biotin streptavidin system in ChIP. We find that the omission of SDS during sonication, the use of fish skin gelatin as blocking agent and choice of streptavidin beads can lead to significantly improved ChIP enrichments and lower background compared to antibodies. We also show that the V5 epitope tag performs equally well under the conditions worked out for streptavidin ChIP and that it may suffer less from the effects of formaldehyde crosslinking. Conclusion The combined use of the very high affinity biotin tag with the less sensitive to crosslinking V5 tag provides for a flexible ChIP platform with potential implications in ChIP sequencing outcomes. PMID:19196479

  8. Electron Temperature Evolution During Local Helicity Injection on the Pegasus Toroidal Experiment

    NASA Astrophysics Data System (ADS)

    Schlossberg, D. J.; Barr, J. L.; Bodner, G. M.; Bongard, M. W.; Fonck, R. J.; Perry, J. M.; Reusch, J. A.; Rodriguez Sanchez, C.

    2016-10-01

    Understanding the electron temperature (Te) evolution during local helicity injection (LHI) is critical for scaling up this non-solenoidal startup technique to MA-class devices. The first comprehensive Te measurements during LHI reveal centrally-peaked profiles with Te > 100 eV for plasma current Ip > 120 kA, toroidal field 0.15 T, and electron density ne 1019 m-3. Te rises and is sustained from just after magnetic relaxation through the plasma decoupling from edge-localized injectors. Results are presented for two injector edge locations: outboard midplane and inboard divertor. Outboard midplane injection couples LHI with inductive drive from poloidal field ramps and radial compression during inward plasma growth. Comparisons of Te at different LHI-to-inductive drive ratios show some profile flattening for higher LHI drive fraction. The latter, constant-shape discharges were necessarily lower performance, with Ip 50 kA and reduced Te , max. Inboard divertor injection achieves higher Ip using minimal inductive drive and thus isolates effects of LHI drive on Te. Initial results in this configuration show Te rising rapidly at the injector location as the discharge grows, settling to a roughly flat profile 100 eV. Thus far, both scenarios provide relatively stable discharges with moderate ne and high-Te, suitable for coupling to auxiliary current drive. Detailed studies of confinement dynamics and discharge optimization are planned for the near future. Work supported by US DOE Grant DE-FG02-96ER54375.

  9. Quantum chemical characterization of zwitterionic structures: Supramolecular complexes for modifying the wettability of oil-water-limestone system.

    PubMed

    Lopez-Chavez, Ernesto; Garcia-Quiroz, Alberto; Gonzalez-Garcia, Gerardo; Orozco-Duran, Gabriela E; Zamudio-Rivera, Luis S; Martinez-Magadan, José M; Buenrostro-Gonzalez, Eduardo; Hernandez-Altamirano, Raul

    2014-06-01

    In this work, we present a quantum chemical study pertaining to some supramolecular complexes acting as wettability modifiers of oil-water-limestone system. The complexes studied are derived from zwitterionic liquids of the types N'-alkyl-bis, N-alquenil, N-cycloalkyl, N-amyl-bis-beta amino acid or salts acting as sparkling agents. We studied two molecules of zwitterionic liquids (ZL10 and ZL13), HOMO and LUMO levels, and the energy gap between them, were calculated, as well as the electron affinity (EA) and ionization potential (IP), chemical potential, chemical hardness, chemical electrophilicity index and selectivity descriptors such Fukui indices. In this work, electrochemical comparison was realized with cocamidopropyl betaine (CPB), which is a structure zwitterionic liquid type, nowadays widely applied in enhanced recovery processes. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Role of Caspase-3 Cleaved IP3R1 on Ca2+ Homeostasis and Developmental Competence of Mouse Oocytes and Eggs

    PubMed Central

    Zhang, Nan; Fissore, Rafael. A.

    2014-01-01

    Apoptosis in most cell types is accompanied by altered Ca2+ homeostasis. During apoptosis, caspase-3 mediated cleavage of the type 1 inositol 1,4,5-trisphosphate receptor (IP3R1) generates a 95-kDa C-terminal fragment (C-IP3R1), which represents the channel domain of the receptor. Aged mouse eggs display abnormal Ca2+ homeostasis and express C-IP3R1, although whether or not C-IP3R1 expression contributes to Ca2+ misregulation or a decrease in developmental competency is unknown. We sought to answer these questions by injecting in mouse oocytes and eggs cRNAs encoding CIP3R1. We found that: 1) expression of C-IP3R1 in eggs lowered the Ca2+ content of the endoplasmic reticulum (ER), although, as C-IP3R1 is quickly degraded at this stage, its expression did not impair pre-implantation embryo development; 2) expression of CIP3R1 in eggs enhanced fragmentation associated with aging; 3) endogenous IP3R1 is required for aging associated apoptosis, as its down-regulation prevented fragmentation, and expression of C-IP3R1 in eggs with downregulated IP3R1 partly restored fragmentation; 4) C-IP3R1 expression in GV oocytes resulted in persistent levels of protein, which abolished the increase in the ER releasable Ca2+ pool that occurs during maturation, undermined the Ca2+ oscillatory ability of matured eggs and their activation potential. Collectively, this study supports a role for IP3R1 and C-IP3R1 in regulating Ca2+ homeostasis and the ER Ca2+ content during oocyte maturation. Nevertheless, the role of C-IP3R1 on Ca2+ homeostasis in aged eggs seems minor, as in MII eggs the majority of endogenous IP3R1 remains intact and C-IP3R1 undergoes rapid turnover. PMID:24692207

  11. Pharmacological profile of dexketoprofen in orofacial pain.

    PubMed

    Miranda, Hugo F; Sierralta, Fernando; Aranda, Nicolás; Noriega, Viviana; Prieto, Juan Carlos

    2016-12-01

    Non-steroidal anti-inflammatory drugs (NSAIDs) may act through others mechanisms, in addition to inhibition of prostaglandin synthesis. These includes cholinergic, NO, serotonergic and opioids pathways. The aim of this work was to evaluate the effect of systemic action of (S)-+-ketoprofen (dexketoprofen, DEX) on pain behaviors using the orofacial formalin test in mice and the potential involvement of cholinergic, NO, serotonergic and opioids pathways. The pretreatment of the mice with 1mg/kg ip of atropine or opoid antagonists: 1mg/kg, ip of NTX or 1mg/kg ip of NTI or 1mg/kg of NOR-BNI ip, did not produce significant change in the ED 50 values of the antinociception to orofacial test induced by DEX. The pretreatment of the mice with 0.5mg/kg ip tropisetron, increased in a significant fashion the values of ED 50 of DEX. When the mice were treated with 5mg/kg ip of L-NAME or 25mg/kg ip of aminoguanidine or 50mg/kg ip of 7-nitroindazole reversed the antinociception of DEX. The findings of this study demonstrate activation of NO and 5-HTpathways play important roles in the systemic antinociceptive effect of DEX in a murine model of inflammatory pain. Copyright © 2016. Published by Elsevier Urban & Partner Sp. z o.o.

  12. Migration features of Ips typographus in the Tatra Mountains: using a genetic method

    Treesearch

    Ferenc Lakatos

    2003-01-01

    The genetic structure of Ips typographus populations in the Tatra Mountains was studied based on the observed differences of gene flow and migration rate. It was a highlighted question as to what extent different natural barriers influence the migration potential of the species.

  13. Competitive Exclusion of Dendroctonus rufipennis Induced by Pheromones of Ips tridens and Dryocoetes affaber (Coleoptera: Scolytidae)

    Treesearch

    Therese M. Poland; John H. Borden

    1998-01-01

    We tested the feasibility of competitive exclusion as a potential management tactic for the spruce beetle, Dendroctonus rufipennis Kirby, using pre-attack baiting with pheromones of 2 secondary species, Ips tridens Mannerheim and Dryocoetes affaber Mannerheim. Spruce beetle attack densities, gallery lengths per...

  14. Psychoses in epilepsy: A comparison of postictal and interictal psychoses.

    PubMed

    Hilger, Eva; Zimprich, Friedrich; Pataraia, Ekaterina; Aull-Watschinger, Susanne; Jung, Rebekka; Baumgartner, Christoph; Bonelli, Silvia

    2016-07-01

    We retrospectively analyzed data of patients with epilepsy (n=1434) evaluated with prolonged EEG monitoring in order to estimate the prevalence of postictal psychosis (PP) and interictal psychosis (IP), to investigate a potential association of psychosis subtype with epilepsy type, and to assess differences between PP and IP. The overall prevalence of psychosis was 5.9% (N=85); prevalence of PP (N=53) and IP (N=32) was 3.7% and 2.2%, respectively. Of patients with psychosis, 97.6% had localization-related epilepsy (LRE). Prevalence of psychosis was highest (9.3%) in patients with temporal lobe epilepsy (TLE). When comparing PP with IP groups on demographic, clinical, and psychopathological variables, patients with IP were younger at occurrence of first psychosis (P=0.048), had a shorter interval between epilepsy onset and first psychosis (P=0.002), and more frequently exhibited schizophreniform traits (conceptual disorganization: P=0.008; negative symptoms: P=0.017) than those with PP. Postictal psychosis was significantly associated with a temporal seizure onset on ictal EEG (P=0.000) and a higher incidence of violent behavior during psychosis (P=0.047). To conclude, our results support the presumption of a preponderance of LRE in patients with psychosis and that of a specific association of TLE with psychosis, in particular with PP. Given the significant differences between groups, PP and IP may represent distinct clinical entities potentially with a different neurobiological background. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Antioxidant behavior of mearnsetin and myricetin flavonoid compounds — A DFT study

    NASA Astrophysics Data System (ADS)

    Sadasivam, K.; Kumaresan, R.

    2011-06-01

    The molecular characteristics of two naturally occurring flavonoid compounds mearnsetin and myricetin have been computed using density functional theory (DFT) approach with B3LYP/6-311G(d,p) level of theory. The computation and analysis of bond dissociation enthalpy magnitudes for all the OH sites for both the compounds clearly denotes the contribution of the B-ring for the antioxidant activity. The analysis has also indicated the higher values of BDE on the C5-OH radical species in both the compounds. The computed vibrational frequency analysis indicates the absence of imaginary frequency in the neutral as well as radical species of both the flavonoid compounds. The ionisation potential (IP) analysis was found to be within the range of the IP of synthetic food additives. In addition, various molecular descriptors such as electron affinity, hardness, softness, electronegativity, electrophilic index have also been calculated and the validity of Koopman's theorem is verified. The plot of frontier molecular orbital and spin density distribution analysis for neutral and the corresponding radical species for both the compounds have been computed and interpreted. The polar nature and their polarizing capacity are well established through the analysis of dipole moment and polarisability magnitudes.

  16. Evolution of a Novel Antiviral Immune-Signaling Interaction by Partial-Gene Duplication

    PubMed Central

    Korithoski, Bryan; Kolaczkowski, Oralia; Mukherjee, Krishanu; Kola, Reema; Earl, Chandra; Kolaczkowski, Bryan

    2015-01-01

    The RIG-like receptors (RLRs) are related proteins that identify viral RNA in the cytoplasm and activate cellular immune responses, primarily through direct protein-protein interactions with the signal transducer, IPS1. Although it has been well established that the RLRs, RIG-I and MDA5, activate IPS1 through binding between the twin caspase activation and recruitment domains (CARDs) on the RLR and a homologous CARD on IPS1, it is less clear which specific RLR CARD(s) are required for this interaction, and almost nothing is known about how the RLR-IPS1 interaction evolved. In contrast to what has been observed in the presence of immune-modulating K63-linked polyubiquitin, here we show that—in the absence of ubiquitin—it is the first CARD domain of human RIG-I and MDA5 (CARD1) that binds directly to IPS1 CARD, and not the second (CARD2). Although the RLRs originated in the earliest animals, both the IPS1 gene and the twin-CARD domain architecture of RIG-I and MDA5 arose much later in the deuterostome lineage, probably through a series of tandem partial-gene duplication events facilitated by tight clustering of RLRs and IPS1 in the ancestral deuterostome genome. Functional differentiation of RIG-I CARD1 and CARD2 appears to have occurred early during this proliferation of RLR and related CARDs, potentially driven by adaptive coevolution between RIG-I CARD domains and IPS1 CARD. However, functional differentiation of MDA5 CARD1 and CARD2 occurred later. These results fit a general model in which duplications of protein-protein interaction domains into novel gene contexts could facilitate the expansion of signaling networks and suggest a potentially important role for functionally-linked gene clusters in generating novel immune-signaling pathways. PMID:26356745

  17. IP voice over ATM satellite: experimental results over satellite channels

    NASA Astrophysics Data System (ADS)

    Saraf, Koroush A.; Butts, Norman P.

    1999-01-01

    IP telephony, a new technology to provide voice communication over traditional data networks, has the potential to revolutionize telephone communication within the modern enterprise. This innovation uses packetization techniques to carry voice conversations over IP networks. This packet switched technology promises new integrated services, and lower cost long-distance communication compared to traditional circuit switched telephone networks. Future satellites will need to carry IP traffic efficiently in order to stay competitive in servicing the global data- networking and global telephony infrastructure. However, the effects of Voice over IP over switched satellite channels have not been investigated in detail. To fully understand the effects of satellite channels on Voice over IP quality; several experiments were conducted at Lockheed Martin Telecommunications' Satellite Integration Lab. The result of those experiments along with suggested improvements for voice communication over satellite are presented in this document. First, a detailed introduction of IP telephony as a suitable technology for voice communication over future satellites is presented. This is followed by procedures for the experiments, along with results and strategies. In conclusion we hope that these capability demonstrations will alleviate any uncertainty regarding the applicability of this technology to satellite networks.

  18. Intraperitoneal administration of tumor-targeting Salmonella typhimurium A1-R inhibits disseminated human ovarian cancer and extends survival in nude mice

    PubMed Central

    Zhang, Yong; Zhao, Ming; Yano, Shuya; Uehara, Fuminari; Yamamoto, Mako; Hiroshima, Yukihiko; Toneri, Makoto; Bouvet, Michael; Matsubara, Hisahiro; Tsuchiya, Hiroyuki; Hoffman, Robert M.

    2015-01-01

    Peritoneal disseminated cancer is highly treatment resistant. We here report the efficacy of intraperitoneal (i.p.) administration of tumor-targeting Salmonella typhimurium A1-R in a nude mouse model of disseminated human ovarian cancer. The mouse model was established by intraperitoneal injection of the human ovarian cancer cell line SKOV3-GFP. Seven days after implantation, mice were treated with S. typhimurium A1-R via intravenous (i.v.) or i.p. administration at the same dose, 5×107 CFU, once per week. Both i.v. and i.p. treatments effected prolonged survival compared with the untreated control group (P=0.025 and P<0.001, respectively). However, i.p. treatment was less toxic than i.v. treatment. Tumor-specific targeting of S. typhimurium A1-R was confirmed with bacterial culture from tumors and various organs and tumor or organ colony formation after i.v. or i.p. injection. Selective tumor targeting was most effective with i.p. administration. The results of the present study show S. typhimurium A1-R has promising clinical potential for disseminated ovarian cancer, especially via i.p. administration. PMID:25957417

  19. A new ionospheric storm scale based on TEC and foF2 statistics

    NASA Astrophysics Data System (ADS)

    Nishioka, Michi; Tsugawa, Takuya; Jin, Hidekatsu; Ishii, Mamoru

    2017-01-01

    In this paper, we propose the I-scale, a new ionospheric storm scale for general users in various regions in the world. With the I-scale, ionospheric storms can be classified at any season, local time, and location. Since the ionospheric condition largely depends on many factors such as solar irradiance, energy input from the magnetosphere, and lower atmospheric activity, it had been difficult to scale ionospheric storms, which are mainly caused by solar and geomagnetic activities. In this study, statistical analysis was carried out for total electron content (TEC) and F2 layer critical frequency (foF2) in Japan for 18 years from 1997 to 2014. Seasonal, local time, and latitudinal dependences of TEC and foF2 variabilities are excluded by normalizing each percentage variation using their statistical standard deviations. The I-scale is defined by setting thresholds to the normalized numbers to seven categories: I0, IP1, IP2, IP3, IN1, IN2, and IN3. I0 represents a quiet state, and IP1 (IN1), IP2 (IN2), and IP3 (IN3) represent moderate, strong, and severe positive (negative) storms, respectively. The proposed I-scale can be used for other locations, such as polar and equatorial regions. It is considered that the proposed I-scale can be a standardized scale to help the users to assess the impact of space weather on their systems.

  20. MLF1 interacting protein: a potential gene therapy target for human prostate cancer?

    PubMed

    Zhang, Lei; Ji, Guoqing; Shao, Yuzhang; Qiao, Shaoyi; Jing, Yuming; Qin, Rongliang; Sun, Huiming; Shao, Chen

    2015-02-01

    Here, we investigated the role of one gene that has been previously associated with human prostate carcinoma cells-myelodysplasia/myeloid leukemia factor 1 interacting protein (MLF1IP)-in order to better ascertain its role in human prostate carcinogenesis. The prostate cancer cell line PC-3 was lentivirally transfected to silence endogenous MLF1IP gene expression, which was confirmed by real-time quantitative PCR (RT-qPCR). Cellomics ArrayScan VTI imaging and MTT assays were conducted to assess cell proliferation. Cell cycle phase arrest and apoptosis were assayed by flow cytometry. Colony formation was assessed by fluorescence microscopy. MLF1IP gene expression was also analyzed by RT-qPCR in sixteen prostate cancer tissue samples and six healthy control prostate tissue samples from human patients. Cell proliferation was significantly inhibited in MLF1IP-silenced cells relative to control cells. G1 phase, S and G2/M phase cell counts were not significantly changed in MLF1IP-silenced cells relative to control cells. Apoptosis was significantly increased in MLF1IP-silenced cells, while MLF1IP-silenced cells displayed a significantly reduced number of cell colonies, compared to control cells. The 16 human prostate cancer tissue samples revealed no clear upregulation or downregulation in MLF1IP gene expression. MLF1IP significantly promotes prostate cancer cell proliferation and colony formation and significantly inhibits apoptosis without affecting cell cycle phase arrest. Further study is required to conclusively determine whether MLF1IP is upregulated in human prostate cancer tumors and to determine the precise cellular mechanism(s) for MLF1IP in prostate carcinogenesis.

  1. 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) Is Selectively Toxic to Primary Dopaminergic Neurons In Vitro

    PubMed Central

    Griggs, Amy M.; Agim, Zeynep S.; Mishra, Vartika R.; Tambe, Mitali A.; Director-Myska, Alison E.; Turteltaub, Kenneth W.; McCabe, George P.; Rochet, Jean-Christophe; Cannon, Jason R.

    2014-01-01

    Parkinson's disease (PD) is the second most common neurodegenerative disease. Much data has linked the etiology of PD to a variety of environmental factors. The majority of cases are thought to arise from a combination of genetic susceptibility and environmental factors. Chronic exposures to dietary factors, including meat, have been identified as potential risk factors. Although heterocyclic amines that are produced during high-temperature meat cooking are known to be carcinogenic, their effect on the nervous system has yet to be studied in depth. In this study, we investigated neurotoxic effects of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a highly abundant heterocyclic amine in cooked meat, in vitro. We tested toxicity of PhIP and the two major phase I metabolites, N-OH-PhIP and 4′-OH-PhIP, using primary mesencephalic cultures from rat embryos. This culture system contains both dopaminergic and nondopaminergic neurons, which allows specificity of neurotoxicity to be readily examined. We find that exposure to PhIP or N-OH-PhIP is selectively toxic to dopaminergic neurons in primary cultures, resulting in a decreased percentage of dopaminergic neurons. Neurite length is decreased in surviving dopaminergic neurons. Exposure to 4′-OH-PhIP did not produce significant neurotoxicity. PhIP treatment also increased formation of oxidative damage markers, 4-hydroxy-2-nonenal (HNE) and 3-nitrotyrosine in dopaminergic neurons. Pretreatment with N-acetylcysteine was protective. Finally, treatment with blueberry extract, a dietary factor with known antioxidant and other protective mechanisms, prevented PhIP-induced toxicity. Collectively, our study suggests, for the first time, that PhIP is selectively toxic to dopaminergic neurons likely through inducing oxidative stress. PMID:24718704

  2. Conserved Kv4 N-terminal domain critical for effects of Kv channel-interacting protein 2.2 on channel expression and gating.

    PubMed

    Bähring, R; Dannenberg, J; Peters, H C; Leicher, T; Pongs, O; Isbrandt, D

    2001-06-29

    Association of Kv channel-interacting proteins (KChIPs) with Kv4 channels leads to modulation of these A-type potassium channels (An, W. F., Bowlby, M. R., Betty, M., Cao, J., Ling, H. P., Mendoza, G., Hinson, J. W., Mattsson, K. I., Strassle, B. W., Trimmer, J. S., and Rhodes, K. J. (2000) Nature 403, 553-556). We cloned a KChIP2 splice variant (KChIP2.2) from human ventricle. In comparison with KChIP2.1, coexpression of KChIP2.2 with human Kv4 channels in mammalian cells slowed the onset of Kv4 current inactivation (2-3-fold), accelerated the recovery from inactivation (5-7-fold), and shifted Kv4 steady-state inactivation curves by 8-29 mV to more positive potentials. The features of Kv4.2/KChIP2.2 currents closely resemble those of cardiac rapidly inactivating transient outward currents. KChIP2.2 stimulated the Kv4 current density in Chinese hamster ovary cells by approximately 55-fold. This correlated with a redistribution of immunoreactivity from perinuclear areas to the plasma membrane. Increased Kv4 cell-surface expression and current density were also obtained in the absence of KChIP2.2 when the highly conserved proximal Kv4 N terminus was deleted. The same domain is required for association of KChIP2.2 with Kv4 alpha-subunits. We propose that an efficient transport of Kv4 channels to the cell surface depends on KChIP binding to the Kv4 N-terminal domain. Our data suggest that the binding is necessary, but not sufficient, for the functional activity of KChIPs.

  3. Effects of the brain-penetrant and selective 5-HT6 receptor antagonist SB-399885 in animal models of anxiety and depression.

    PubMed

    Wesołowska, Anna; Nikiforuk, Agnieszka

    2007-04-01

    The effects of a selective 5-HT(6) receptor antagonist, SB-399885 (N-[3,5-dichloro-2-(methoxy)phenyl]-4-(methoxy)-3-(1-piperazinyl)benzenesulfonamide), were evaluated in behavioural tests sensitive to clinically effective anxiolytic- and antidepressant-compounds using diazepam and imipramine as reference drugs. In the Vogel conflict drinking test in rats, SB-399885 (1-3mg/kg i.p.) caused an anxiolytic-like activity comparable to that of diazepam (2.5-5mg/kg i.p.). An anxiolytic-like effect was also seen in the elevated plus-maze test in rats, where SB-399885 (0.3-3mg/kg i.p.) was slightly weaker than diazepam (2.5-5mg/kg i.p.). In the four-plate test in mice, SB-399885 (3-20mg/kg i.p.) showed an anxiolytic-like effect which was weaker than that produced by diazepam (2.5-5mg/kg i.p.). In the forced swim test in rats, SB-399885 (10mg/kg i.p.) significantly shortened the immobility time and the effect was stronger than that of imipramine (30mg/kg i.p.). In the forced swim test in mice, SB-399885 (20-30mg/kg i.p.) had an anti-immobility action, comparable to imipramine (30mg/kg i.p.) and also in the tail suspension test in mice, SB-399885 (10-30mg/kg i.p.) had an antidepressant-like effect, though was weaker than imipramine (10-20mg/kg i.p.). The tested 5-HT(6) antagonist (3-20mg/kg i.p.) shortened the walking time of rats in the open field test and, at a dose of 30mg/kg i.p. reduced the locomotor activity of mice. SB-399885 (in doses up to 30mg/kg i.p.) did not affect motor coordination in mice and rats tested in the rota-rod test. Such data indicate that the selective 5-HT(6) receptor antagonist SB-399885had specific effects, indicative of this compound's anxiolytic and antidepressant potential.

  4. White organic light-emitting diodes with Zn-complexes.

    PubMed

    Kim, Dong-Eun; Shin, Hoon-Kyu; Kim, Nam-Kyu; Lee, Burm-Jong; Kwon, Young-Soo

    2014-02-01

    This paper reviews OLEDs fabricated using Zn-complexes. Zn(HPB)2, Zn(HPB)q, and Zn(phen)q were synthesized as new electroluminescence materials. The electron affinity (EA) and ionization potential (IP) of Zn complexes were also determined and devices were characterized. Zn complexes such as Zn(HPB)2, Zn(HPB)q, and Zn(phen)q were found to exhibit blue and yellow emissions with wavelengths of 455, 532, and 535 nm, respectively. On the other hand, Zn(HPB)2 and Zn(HPB)q were applied as hole-blocking materials. As a result, the OLED efficiency by using Zn(HPB)2 as a hole-blocking material was improved. In particular, the OLED property of Zn(HPB)2 was found to be better than that of Zn(HPB)q. Moreover, Zn(phen)q was used as an electron-transporting material and compared with Alq3. The performance of the device with Zn(phen)q as an electron-transporting material was improved compared with Alq3-based devices. The Zn complexes can possibly be used as hole-blocking and electron-transporting materials in OLED devices. A white emission was ultimately realized from the OLED devices using Zn-complexes as inter-layer components.

  5. Imidazoline binding sites mediates anticompulsive-like effect of agmatine in marble-burying behavior in mice.

    PubMed

    Dixit, Madhura P; Thakre, Prajwal P; Pannase, Akshay S; Aglawe, Manish M; Taksande, Brijesh G; Kotagale, Nandkishor R

    2014-06-05

    Agmatine is a cationic amine formed by decarboxylation of l-arginine by the mitochondrial enzyme arginine decarboxylase and widely distributed in mammalian brain. Although the precise function of endogenous agmatine has been largely remained unclear, its exogenous administration demonstrated beneficial effects in several neurological and psychiatric disorders. This study was planned to examine the role of imidazoline binding sites in the anticompulsive-like effect of agmatine on marble-burying behavior. Agmatine (20 and 40mg/kg, ip), mixed imidazoline I1/α2 agonists clonidine (60µg/kg, ip) and moxonidine (0.25mg/kg, ip), and imidazoline I2 agonist 2- BFI (10mg/kg, ip) showed significant inhibition of marble burying behavior in mice. In combination studies, the anticompulsive-like effect of agmatine (10mg/kg, ip) was significantly potentiated by prior administration of moxonidine (0.25mg/kg, ip) or clonidine (30µg/kg,) or 2-BFI (5mg/kg, ip). Conversely, efaroxan (1mg/kg, ip), an I1 antagonist and idazoxan (0.25mg/kg, ip), an I2 antagonist completely blocked the anticompulsive-like effect of agmatine (10mg/kg, ip). These drugs at doses used here did not influence the basal locomotor activity in experimental animals. These results clearly indicated the involvement of imidazoline binding sites in anti-compulsive-like effect of agmatine. Thus, imidazoline binding sites can be explored further as novel therapeutic target for treatment of anxiety and obsessive compulsive disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. A DFT study for the structural and electronic properties of Zn m Se n nanoclusters

    NASA Astrophysics Data System (ADS)

    Yadav, Phool Singh; Pandey, Dheeraj Kumar

    2012-09-01

    An ab initio study has been performed for the stability, structural and electronic properties of 19 small zinc selenide Zn m Se n ( m + n = 2-4) nanoclusters. Out of these nanoclusters, one nanocluster is found to be unstable due to its imaginary vibrational frequency. A B3LYP-DFT/6-311G(3df) method is used in the optimization of the geometries of the nanoclusters. We have calculated the zero point energy (ZPE), which is ignored by the other workers. The binding energies (BE), HOMO-LUMO gaps and bond lengths have been obtained for all the optimized nanoclusters. For the same value of ` m' and ` n', we designate the most stable structure the one, which has maximum final binding energy (FBE) per atom. The adiabatic and vertical ionization potentials (IP) and electron affinities (EA), dipole moments and charge on atoms have been investigated for the most stable nanoclusters. For the same value of ` m' and ` n', the nanocluster containing maximum number of Se atoms is found to be most stable.

  7. Luminol modified polycarbazole and poly(o-anisidine): Theoretical insights compared with experimental data.

    PubMed

    Jadoun, Sapana; Verma, Anurakshee; Riaz, Ufana

    2018-06-07

    With the aim to explore the effect of luminol as a multifunctional dopant for conjugated polymers, the present study reports the ultrasound-assisted doping of polycarbazole (PCz) and poly(o-anisidine) (PAnis) with luminol in basic, acidic and neutral media. The synthesized homopolymers and luminol doped polymers were characterized using FT-IR, UV-visible and XRD studies while the photo-physical properties were investigated via fluorescence spectroscopy. Density functional theory (DFT) calculations were performed to get insights into the structural, optical, and electronic properties of homopolymers of polycarbazole (PCz) and poly(o-anisidine) (PAnis). Vibrational bands B3LYP/6-311G (d,p) level, UV-vis spectral bands and electronic properties such as ionization potentials (IP), electron affinities (EA) and HOMO-LUMO band gap energies of the homopolymers and doped polymers were calculated and compared. Results revealed that luminol doped polymers showed different photo-physical characteristics in acidic, basic and neutral media which could be tuned to obtain near infrared (NIR) emitting polymers. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. A key to the mites associated with flying Ips typographus in South Germany

    Treesearch

    John C. Moser; H. Bogenschutz

    1984-01-01

    A key identifies 32 species of mites associated with flying Ips typographus collected from nondestructive pheromone traps in South Germany. Fifteen species were judged phoretic because they were attached to the beetles. The biologies of most of the 32 species are unknown, but three are potential predators.

  9. Teaching Note--Asserting Social Work's Role in Developing an Interprofessional Education Project

    ERIC Educational Resources Information Center

    Kobayashi, Rie; Fitzgerald, Cindy

    2017-01-01

    Interprofessional (IP) education is an essential component of today's health care education. IP education has been recognized and supported for its potential to educate workforce-ready health care clinicians with the knowledge and skills, necessary to collaboratively deliver high-quality, client-centered care. While social work's reflective,…

  10. Characteristics of individuals with high information potential in government research and development organizations.

    NASA Technical Reports Server (NTRS)

    Holland, W. E.

    1972-01-01

    In order to study focal individuals within informal communications networks, a special variable was constructed: information potential (IP) was defined as the information-source value placed on an individual by his colleagues. Four hypotheses involving IP were tested in three R&D organizations using questionnaires and pencil-and-paper tests. Results indicated that the individual with high IP used more and different sources of technical information, was seen to be a credible information source and to have a strong ability to associate seemingly unrelated ideas, and was as approachable as the other members of his organization. Four tentative conclusions may be drawn from this study concerning the person with high IP. He is (1) an identifiable individual in several different kinds of organizations; (2) a distinctive information transceiver (transmitter and receiver); (3) both a producer and a catalyst in his own organization; and (4) an extender and an amplifier of information search. To affect the efficiency of informal information flow, the research manager's best hope for positively influencing informal networks lies in the identification and motivation of the special communicators in his organization.

  11. Modulation by clamping: Kv4 and KChIP interactions.

    PubMed

    Wang, Kewei

    2008-10-01

    The rapidly inactivating (A-type) potassium channels regulate membrane excitability that defines the fundamental mechanism of neuronal functions such as pain signaling. Cytosolic Kv channel-interacting proteins KChIPs that belong to neuronal calcium sensor (NCS) family of calcium binding EF-hand proteins co-assemble with Kv4 (Shal) alpha subunits to form a native complex that encodes major components of neuronal somatodendritic A-type K+ current, I(SA), in neurons and transient outward current, I(TO), in cardiac myocytes. The specific binding of auxiliary KChIPs to the Kv4 N-terminus results in modulation of gating properties, surface expression and subunit assembly of Kv4 channels. Here, I attempt to emphasize the interaction between KChIPs and Kv4 based on recent progress made in understanding the structure complex in which a single KChIP1 molecule laterally clamps two neighboring Kv4.3 N-termini in a 4:4 manner. Greater insights into molecular mechanism between KChIPs and Kv4 interaction may provide therapeutic potentials of designing compounds aimed at disrupting the protein-protein interaction for treatment of membrane excitability-related disorders.

  12. Speech perception benefits of internet versus conventional telephony for hearing-impaired individuals.

    PubMed

    Mantokoudis, Georgios; Dubach, Patrick; Pfiffner, Flurin; Kompis, Martin; Caversaccio, Marco; Senn, Pascal

    2012-07-16

    Telephone communication is a challenge for many hearing-impaired individuals. One important technical reason for this difficulty is the restricted frequency range (0.3-3.4 kHz) of conventional landline telephones. Internet telephony (voice over Internet protocol [VoIP]) is transmitted with a larger frequency range (0.1-8 kHz) and therefore includes more frequencies relevant to speech perception. According to a recently published, laboratory-based study, the theoretical advantage of ideal VoIP conditions over conventional telephone quality has translated into improved speech perception by hearing-impaired individuals. However, the speech perception benefits of nonideal VoIP network conditions, which may occur in daily life, have not been explored. VoIP use cannot be recommended to hearing-impaired individuals before its potential under more realistic conditions has been examined. To compare realistic VoIP network conditions, under which digital data packets may be lost, with ideal conventional telephone quality with respect to their impact on speech perception by hearing-impaired individuals. We assessed speech perception using standardized test material presented under simulated VoIP conditions with increasing digital data packet loss (from 0% to 20%) and compared with simulated ideal conventional telephone quality. We monaurally tested 10 adult users of cochlear implants, 10 adult users of hearing aids, and 10 normal-hearing adults in the free sound field, both in quiet and with background noise. Across all participant groups, mean speech perception scores using VoIP with 0%, 5%, and 10% packet loss were 15.2% (range 0%-53%), 10.6% (4%-46%), and 8.8% (7%-33%) higher, respectively, than with ideal conventional telephone quality. Speech perception did not differ between VoIP with 20% packet loss and conventional telephone quality. The maximum benefits were observed under ideal VoIP conditions without packet loss and were 36% (P = .001) for cochlear implant users, 18% (P = .002) for hearing aid users, and 53% (P = .001) for normal-hearing adults. With a packet loss of 10%, the maximum benefits were 30% (P = .002) for cochlear implant users, 6% (P = .38) for hearing aid users, and 33% (P = .002) for normal-hearing adults. VoIP offers a speech perception benefit over conventional telephone quality, even when mild or moderate packet loss scenarios are created in the laboratory. VoIP, therefore, has the potential to significantly improve telecommunication abilities for the large community of hearing-impaired individuals.

  13. Speech Perception Benefits of Internet Versus Conventional Telephony for Hearing-Impaired Individuals

    PubMed Central

    Dubach, Patrick; Pfiffner, Flurin; Kompis, Martin; Caversaccio, Marco

    2012-01-01

    Background Telephone communication is a challenge for many hearing-impaired individuals. One important technical reason for this difficulty is the restricted frequency range (0.3–3.4 kHz) of conventional landline telephones. Internet telephony (voice over Internet protocol [VoIP]) is transmitted with a larger frequency range (0.1–8 kHz) and therefore includes more frequencies relevant to speech perception. According to a recently published, laboratory-based study, the theoretical advantage of ideal VoIP conditions over conventional telephone quality has translated into improved speech perception by hearing-impaired individuals. However, the speech perception benefits of nonideal VoIP network conditions, which may occur in daily life, have not been explored. VoIP use cannot be recommended to hearing-impaired individuals before its potential under more realistic conditions has been examined. Objective To compare realistic VoIP network conditions, under which digital data packets may be lost, with ideal conventional telephone quality with respect to their impact on speech perception by hearing-impaired individuals. Methods We assessed speech perception using standardized test material presented under simulated VoIP conditions with increasing digital data packet loss (from 0% to 20%) and compared with simulated ideal conventional telephone quality. We monaurally tested 10 adult users of cochlear implants, 10 adult users of hearing aids, and 10 normal-hearing adults in the free sound field, both in quiet and with background noise. Results Across all participant groups, mean speech perception scores using VoIP with 0%, 5%, and 10% packet loss were 15.2% (range 0%–53%), 10.6% (4%–46%), and 8.8% (7%–33%) higher, respectively, than with ideal conventional telephone quality. Speech perception did not differ between VoIP with 20% packet loss and conventional telephone quality. The maximum benefits were observed under ideal VoIP conditions without packet loss and were 36% (P = .001) for cochlear implant users, 18% (P = .002) for hearing aid users, and 53% (P = .001) for normal-hearing adults. With a packet loss of 10%, the maximum benefits were 30% (P = .002) for cochlear implant users, 6% (P = .38) for hearing aid users, and 33% (P = .002) for normal-hearing adults. Conclusions VoIP offers a speech perception benefit over conventional telephone quality, even when mild or moderate packet loss scenarios are created in the laboratory. VoIP, therefore, has the potential to significantly improve telecommunication abilities for the large community of hearing-impaired individuals. PMID:22805169

  14. Potential energy surfaces of LaH + and LaH + 2

    NASA Astrophysics Data System (ADS)

    Das, Kalyan K.; Balasubramanian, K.

    1991-03-01

    Using the complete active space multiconfiguration self-consistent field (CAS-MCSCF) followed by full second-order configuration interaction (SOCI) calculations, 16 electronic states of LaH+ and 8 electronic states of LaH+2 are investigated. The potential energy surface of these electronic states of LaH+2 and LaH+ are computed. These calculations show that the 3F(5d2) ground state of La+ ion forms a weak complex with H2. The La+(1D) excited state inserts into H2 with a small barrier (<8 kcal/mol) to form the 1A1 ground state of LaH+2 (re=2.057 Å, θe=106°). At the SOCI level of theory LaH+2 is found to be 11 kcal/mol more stable than La+(3F)+H2. Our calculations explain the experimental observations on La++H2→LaH++H reaction. The adiabatic ionization potential (IP) of LaH2 and LaH are calculated as 5.23 and 5.33 eV, respectively. The ground state of LaH+ was found to be a 2Δ state. We compute De(LaH+) and De(HLa-H+) as 2.54 eV in excellent agreement with the experimental De(LaH+)=2.57 eV measured by Armentrout and co-workers. The spin-orbit effects of LaH+ were also studied using the relativistic configuration interaction (RCI) method.

  15. Creation of a competency-based professional development program for infection preventionists guided by the APIC Competency Model: steps in the process.

    PubMed

    Bernard, Heather; Hackbarth, Diana; Olmsted, Russell N; Murphy, Denise

    2018-06-07

    Infection Preventionists have varying levels of educational preparation. Many have no prior experience in IP. The diversity makes design of professional development programs challenging. Recent surveys suggest that only about half of practicing IPs are board certified. There is an urgent need to employ competent IP's to drive improvement in patient outcomes. This is a project that utilized the APIC Competency Model to create a professional development program characterizing three career stages. Methods included a review of literature on professional development; a survey of IP competence; an assessment of job descriptions and performance evaluations; and a crosswalk of IP competencies. The professional development program includes competency - based IP job descriptions and performance evaluations for each career stage; a professional portfolio; and a toolkit for supervisors. Participants agreed that application of the model resulted in tools which are more closely aligned with current roles for IPs; and increased satisfaction and motivation with the new program. Competent and knowledgeable IP's are crucial to optimizing efficacy of IPC programs. A professional development program has the potential to guide staff orientation, improve satisfaction and retention, improve patient outcomes and promote a positive trajectory in advancing practice. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  16. Interferon-gamma improves impaired dentinogenic and immunosuppressive functions of irreversible pulpitis-derived human dental pulp stem cells

    PubMed Central

    Sonoda, Soichiro; Yamaza, Haruyoshi; Ma, Lan; Tanaka, Yosuke; Tomoda, Erika; Aijima, Reona; Nonaka, Kazuaki; Kukita, Toshio; Shi, Songtao; Nishimura, Fusanori; Yamaza, Takayoshi

    2016-01-01

    Clinically, irreversible pulpitis is treated by the complete removal of pulp tissue followed by replacement with artificial materials. There is considered to be a high potential for autologous transplantation of human dental pulp stem cells (DPSCs) in endodontic treatment. The usefulness of DPSCs isolated from healthy teeth is limited. However, DPSCs isolated from diseased teeth with irreversible pulpitis (IP-DPSCs) are considered to be suitable for dentin/pulp regeneration. In this study, we examined the stem cell potency of IP-DPSCs. In comparison with healthy DPSCs, IP-DPSCs expressed lower colony-forming capacity, population-doubling rate, cell proliferation, multipotency, in vivo dentin regeneration, and immunosuppressive activity, suggesting that intact IP-DPSCs may be inadequate for dentin/pulp regeneration. Therefore, we attempted to improve the impaired in vivo dentin regeneration and in vitro immunosuppressive functions of IP-DPSCs to enable dentin/pulp regeneration. Interferon gamma (IFN-γ) treatment enhanced in vivo dentin regeneration and in vitro T cell suppression of IP-DPSCs, whereas treatment with tumor necrosis factor alpha did not. Therefore, these findings suggest that IFN-γ may be a feasible modulator to improve the functions of impaired IP-DPSCs, suggesting that autologous transplantation of IFN-γ-accelerated IP-DPSCs might be a promising new therapeutic strategy for dentin/pulp tissue engineering in future endodontic treatment. PMID:26775677

  17. Electronic surveillance systems in infection prevention: Organizational support, program characteristics, and user satisfaction

    PubMed Central

    Grota, Patti G.; Stone, Patricia W.; Jordan, Sarah; Pogorzelska, Monika; Larson, Elaine

    2012-01-01

    Background The use of electronic surveillance systems (ESSs) is gradually increasing in infection prevention and control programs. Little is known about the characteristics of hospitals that have a ESS, user satisfaction with ESSs, and organizational support for implementation of ESSs. Methods A total of 350 acute care hospitals in California were invited to participate in a Web-based survey; 207 hospitals (59%) agreed to participate. The survey included a description of infection prevention and control department staff, where and how they spent their time, a measure of organizational support for infection prevention and control, and reported experience with ESSs. Results Only 23% (44/192) of responding infection prevention and control departments had an ESS. No statistically significant difference was seen in how and where infection preventionists (IPs) who used an ESS and those who did not spend their time. The 2 significant predictors of whether an ESS was present were score on the Organizational Support Scale (odds ratio [OR], 1.10; 95% confidence interval [CI], 1.02-1.18) and hospital bed size (OR, 1.004; 95% CI, 1.00-1.007). Organizational support also was positively correlated with IP satisfaction with the ESS, as measured on the Computer Usability Scale (P = .02). Conclusion Despite evidence that such systems may improve efficiency of data collection and potentially improve patient outcomes, ESSs remain relatively uncommon in infection prevention and control programs. Based on our findings, organizational support appears to be a major predictor of the presence, use, and satisfaction with ESSs in infection prevention and control programs. PMID:20176411

  18. Electronic surveillance systems in infection prevention: organizational support, program characteristics, and user satisfaction.

    PubMed

    Grota, Patti G; Stone, Patricia W; Jordan, Sarah; Pogorzelska, Monika; Larson, Elaine

    2010-09-01

    The use of electronic surveillance systems (ESSs) is gradually increasing in infection prevention and control programs. Little is known about the characteristics of hospitals that have a ESS, user satisfaction with ESSs, and organizational support for implementation of ESSs. A total of 350 acute care hospitals in California were invited to participate in a Web-based survey; 207 hospitals (59%) agreed to participate. The survey included a description of infection prevention and control department staff, where and how they spent their time, a measure of organizational support for infection prevention and control, and reported experience with ESSs. Only 23% (44/192) of responding infection prevention and control departments had an ESS. No statistically significant difference was seen in how and where infection preventionists (IPs) who used an ESS and those who did not spend their time. The 2 significant predictors of whether an ESS was present were score on the Organizational Support Scale (odds ratio [OR], 1.10; 95% confidence interval [CI], 1.02-1.18) and hospital bed size (OR, 1.004; 95% CI, 1.00-1.007). Organizational support also was positively correlated with IP satisfaction with the ESS, as measured on the Computer Usability Scale (P = .02). Despite evidence that such systems may improve efficiency of data collection and potentially improve patient outcomes, ESSs remain relatively uncommon in infection prevention and control programs. Based on our findings, organizational support appears to be a major predictor of the presence, use, and satisfaction with ESSs in infection prevention and control programs.

  19. What Is the Role of Informal Healthcare Providers in Developing Countries? A Systematic Review

    PubMed Central

    Sudhinaraset, May; Ingram, Matthew; Lofthouse, Heather Kinlaw; Montagu, Dominic

    2013-01-01

    Informal health care providers (IPs) comprise a significant component of health systems in developing nations. Yet little is known about the most basic characteristics of performance, cost, quality, utilization, and size of this sector. To address this gap we conducted a comprehensive literature review on the informal health care sector in developing countries. We searched for studies published since 2000 through electronic databases PubMed, Google Scholar, and relevant grey literature from The New York Academy of Medicine, The World Bank, The Center for Global Development, USAID, SHOPS (formerly PSP-One), The World Health Organization, DFID, Human Resources for Health Global Resource Center. In total, 334 articles were retrieved, and 122 met inclusion criteria and chosen for data abstraction. Results indicate that IPs make up a significant portion of the healthcare sector globally, with almost half of studies (48%) from Sub-Saharan Africa. Utilization estimates from 24 studies in the literature of IP for healthcare services ranged from 9% to 90% of all healthcare interactions, depending on the country, the disease in question, and methods of measurement. IPs operate in a variety of health areas, although baseline information on quality is notably incomplete and poor quality of care is generally assumed. There was a wide variation in how quality of care is measured. The review found that IPs reported inadequate drug provision, poor adherence to clinical national guidelines, and that there were gaps in knowledge and provider practice; however, studies also found that the formal sector also reported poor provider practices. Reasons for using IPs included convenience, affordability, and social and cultural effects. Recommendations from the literature amount to a call for more engagement with the IP sector. IPs are a large component of nearly all developing country health systems. Research and policies of engagement are needed. PMID:23405101

  20. ePIANNO: ePIgenomics ANNOtation tool.

    PubMed

    Liu, Chia-Hsin; Ho, Bing-Ching; Chen, Chun-Ling; Chang, Ya-Hsuan; Hsu, Yi-Chiung; Li, Yu-Cheng; Yuan, Shin-Sheng; Huang, Yi-Huan; Chang, Chi-Sheng; Li, Ker-Chau; Chen, Hsuan-Yu

    2016-01-01

    Recently, with the development of next generation sequencing (NGS), the combination of chromatin immunoprecipitation (ChIP) and NGS, namely ChIP-seq, has become a powerful technique to capture potential genomic binding sites of regulatory factors, histone modifications and chromatin accessible regions. For most researchers, additional information including genomic variations on the TF binding site, allele frequency of variation between different populations, variation associated disease, and other neighbour TF binding sites are essential to generate a proper hypothesis or a meaningful conclusion. Many ChIP-seq datasets had been deposited on the public domain to help researchers make new discoveries. However, researches are often intimidated by the complexity of data structure and largeness of data volume. Such information would be more useful if they could be combined or downloaded with ChIP-seq data. To meet such demands, we built a webtool: ePIgenomic ANNOtation tool (ePIANNO, http://epianno.stat.sinica.edu.tw/index.html). ePIANNO is a web server that combines SNP information of populations (1000 Genomes Project) and gene-disease association information of GWAS (NHGRI) with ChIP-seq (hmChIP, ENCODE, and ROADMAP epigenomics) data. ePIANNO has a user-friendly website interface allowing researchers to explore, navigate, and extract data quickly. We use two examples to demonstrate how users could use functions of ePIANNO webserver to explore useful information about TF related genomic variants. Users could use our query functions to search target regions, transcription factors, or annotations. ePIANNO may help users to generate hypothesis or explore potential biological functions for their studies.

  1. Factors affecting human heterocyclic amine intake and the metabolism of PhIP.

    PubMed

    Knize, Mark G; Kulp, Kristen S; Salmon, Cynthia P; Keating, Garrett A; Felton, James S

    2002-09-30

    We are working to understand possible human health effects from exposure to heterocyclic amines that are formed in meat during cooking. Laboratory-cooked beef, pork, and chicken are capable of producing tens of nanograms of MeIQx, IFP, and PhIP per gram of meat and smaller amounts of other heteroyclic amines. Well-done restaurant-cooked beef, pork, and chicken may contain PhIP and IFP at concentrations as high as tens of nanograms per gram and MeIQx at levels up to 3 ng/g. Although well-done chicken breast prepared in the laboratory may contain large amounts of PhIP, a survey of flame-grilled meat samples cooked in private homes showed PhIP levels in beef steak and chicken breast are not significantly different (P=0.36). The extremely high PhIP levels reported in some studies of grilled chicken are not seen in home-cooked samples.Many studies suggest individuals may have varying susceptibility to carcinogens and that diet may influence metabolism, thus affecting cancer susceptibility. To understand the human metabolism of PhIP, we examined urinary metabolites of PhIP in volunteers following a single well-done meat exposure. Using solid-phase extraction and LC/MS/MS, we quantified four major PhIP metabolites in human urine. In addition to investigating individual variation, we examined the interaction of PhIP with a potentially chemopreventive food. In a preliminary study of the effect of broccoli on PhIP metabolism, we fed chicken to six volunteers before and after eating steamed broccoli daily for 3 days. Preliminary results suggest that broccoli, which contains isothiocyanates shown to induce Phases I and II metabolism in vitro, may affect both the rate of metabolite excretion and the metabolic products of a dietary carcinogen. This newly developed methodology will allow us to assess prevention strategies that reduce the possible risks associated with PhIP exposure.

  2. Buffering Impostor Feelings with Kindness: The Mediating Role of Self-compassion between Gender-Role Orientation and the Impostor Phenomenon

    PubMed Central

    Patzak, Alexandra; Kollmayer, Marlene; Schober, Barbara

    2017-01-01

    The impostor phenomenon (IP) refers to high-achievers who underestimate their abilities and thus fear being unmasked as impostors. IP sufferers attribute their success to factors other than their abilities, entailing negative emotions, unfavorable motivations, and reduced well-being. The IP was originally conceptualized as a predominantly female experience, and is thus seen as an important psychological barrier for female academic careers. Empirical findings of gender differences in the IP are equivocal, but sparse research on associations between gender-role orientation and the IP indicates that feminine students suffer more intensely from the IP than masculine students. Femininity and masculinity are also related to self-compassion, a rather young construct that enhances emotional resilience, well-being, and academic achievement. Self-compassion involves being kind to oneself when failing, perceiving one’s inadequacies as part of the human condition, and being mindful about negative aspects of oneself. It reduces fear of failure, denial of competences, and self-doubts which are central components of the IP. However, relations between self-compassion and the IP have not been investigated to date. In this study, we examine self-compassion as a potential resilience factor against the IP, taking gender and gender-role orientation into account. In a cross-sectional online survey, we investigated 459 (315 female) high-achieving first-year undergraduate students. Results include: Female, feminine, and undifferentiated students score higher on measures of the IP and lower on measures of self-compassion than male, masculine, or androgynous students. Higher levels of the IP are associated with lower levels of self-compassion across all students tested. Self-compassion further mediates the relationship between gender-role orientation and the IP. Interventions to enhance self-compassion might thus be an effective way to overcome impostor feelings. Female, feminine, and undifferentiated students might benefit most from facilitation of self-compassion in education. PMID:28798714

  3. Freeze-Quench Magnetic Circular Dichroism Spectroscopic Study of the "Very Rapid" Intermediate in Xanthine Oxidase.

    PubMed

    Jones, Robert M.; Inscore, Frank E.; Hille, Russ; Kirk, Martin L.

    1999-11-01

    Freeze-quench magnetic circular dichroism spectroscopy (MCD) has been used to trap and study the excited-state electronic structure of the Mo(V) active site in a xanthine oxidase intermediate generated with substoichiometric concentrations of the slow substrate 2-hydroxy-6-methylpurine. EPR spectroscopy has shown that the intermediate observed in the MCD experiment is the "very rapid" intermediate, which lies on the main catalytic pathway. The low-energy (< approximately 30 000 cm(-1)) C-term MCD of this intermediate is remarkably similar to that of the model compound LMoO(bdt) (L = hydrotris(3,5-dimethyl-1-pyrazolyl)borate; bdt = 1,2-benzenedithiolate), and the MCD bands have been assigned as dithiolate S(ip) --> Mo d(xy) and S(op) --> Mo d(xz,yz) LMCT transitions. These transitions result from a coordination geometry of the intermediate where the Mo=O bond is oriented cis to the ene-1,2-dithiolate of the pyranopterin. Since X-ray crystallography has indicated that a terminal sulfido ligand is oriented cis to the ene-1,2-dithiolate in oxidized xanthine oxidase related Desulfovibrio gigas aldehyde oxidoreductase, we have suggested that a conformational change occurs upon substrate binding. The substrate-mediated conformational change is extremely significant with respect to electron-transfer regeneration of the active site, as covalent interactions between the redox-active Mo d(xy) orbital and the S(ip) orbitals of the ene-1,2-dithiolate are maximized when the oxo ligand is oriented cis to the dithiolate plane. This underlies the importance of the ene-1,2-dithiolate portion of the pyranopterin in providing an efficient superexchange pathway for electron transfer. The results of this study indicate that electron-transfer regeneration of the active site may be gated by the orientation of the Mo=O bond relative to the ene-1,2-dithiolate chelate. Poor overlap between the Mo d(xy) orbital and the S(ip) orbitals of the dithiolate in the oxidized enzyme geometry may provide a means of preventing one-electron reduction of the active site, resulting in enzyme inhibition with respect to the two-electron oxidation of native substrates.

  4. Methacrylate-Stitched β-Cyclodextrin Embedded with Nanogold/Nanotitania: A Skin Adhesive Device for Enhanced Transdermal Drug Delivery.

    PubMed

    Anirudhan, T S; Nair, Syam S; Sasidharan, Athira V

    2017-12-27

    Transdermal (TD) drug delivery is a more attractive technique for drug delivery compared to oral and intravenous injection. However, the permeation of drug molecules across the skin is difficult due to the presence of highly ordered lipid barrier. This study details the development of a novel TD system, which has the potential to simultaneously enhance the skin permeability and adhesion behavior. Ibuprofen (IP) was selected as model drug. The ability of gold nanoparticle (AuNP) and hydrophobic titanium nanotube (TNT) to enhance the skin permeability was explored. Additionally, β-cyclodextrin (βCD), which can exceptionally encapsulate poorly water-soluble drugs, is grafted with methacrylates to improve the skin adhesion property. Finally, Au-TNT nanocomposite was deposited onto methacrylate-grafted βCD matrix. The developed material was characterized through NMR spectroscopy, infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Raman spectroscopy. The characteristics of the film, including water vapor permeability (WVP), thermomechanical properties, etc., were examined in terms of Au-TNT content. The TD delivery of IP with different concentrations of Au-TNT was evaluated via an in vitro skin permeation study through rat skin. It is revealed that the prepared TD film exhibited an improved drug-delivery performance due to the synergistic action of AuNP and hydrophobic TNT. The cumulative percent of IP delivered across the skin is extremely depending on nanofiller content, lipophilicity, and thickness of the membrane, and the device incorporated with 4.0% Au-TNT displayed the best performance. In addition, a study on storage stability was performed by storing the films for 2 months at different temperatures. The study revealed that the device possessed excellent storage stability when stored at low temperature. The developed film offers excellent WVP, drug encapsulation efficiency, thermomechanical properties, and skin adhesion behavior. Moreover, the device was cosmetically attractive, noncytotoxic, and resistant to microbial growth and hence extremely reliable for skin application. The developed skin permeation strategy may open new avenues in TD drug delivery.

  5. Exploring the surface reactivity of 3d metal endofullerenes: a density-functional theory study.

    PubMed

    Estrada-Salas, Rubén E; Valladares, Ariel A

    2009-09-24

    Changes in the preferential sites of electrophilic, nucleophilic, and radical attacks on the pristine C60 surface with endohedral doping using 3d transition metal atoms were studied via two useful reactivity indices, namely the Fukui functions and the molecular electrostatic potential. Both of these were calculated at the density functional BPW91 level of theory with the DNP basis set. Our results clearly show changes in the preferential reactivity sites on the fullerene surface when it is doped with Mn, Fe, Co, or Ni atoms, whereas there are no significant changes in the preferential reactivity sites on the C60 surface upon endohedral doping with Cu and Zn atoms. Electron affinities (EA), ionization potentials (IP), and HOMO-LUMO gaps (Eg) were also calculated to complete the study of the endofullerene's surface reactivity. These findings provide insight into endofullerene functionalization, an important issue in their application.

  6. Radical scavenging behavior of eriodictyol and fustin flavonoid compounds - A DFT study

    NASA Astrophysics Data System (ADS)

    Sadasivam, K.; Praveena, R.; Anbakzhakan, K.

    2018-05-01

    The density functional theory (DFT) protocol together with B3LYP/6-311G(d,p) level of theory has been utilized to explore and compare the structural features and molecular characteristics of two naturally occurring flavonoid compounds eriodictyol and fustin. The -OH bond dissociation energy (BDE) for all the radical species have been computed and interpreted in accordance with the radical scavenging activity. The ionization potential (IP) value of fustin flavonoid compound was found to be within the range of synthetic food additives. The polar nature and their capacity to polarise other atoms are established through the dipole moment analysis. Additionally, various parameters that are relevant to chemical potential such as electron affinity, hardness, softness, electro negativity and electrophilic index were calculated and analysed in the light of quercetin flavonoid compound in view of their antioxidant activity. The antioxidant capability of fustin is found to be superior to eriodictyol flavonoid.

  7. Differential expression of three T lymphocyte-activating CXC chemokines by human atheroma-associated cells

    PubMed Central

    Mach, François; Sauty, Alain; Iarossi, Albert S.; Sukhova, Galina K.; Neote, Kuldeep; Libby, Peter; Luster, Andrew D.

    1999-01-01

    Activated T lymphocytes accumulate early in atheroma formation and persist at sites of lesion growth and rupture, suggesting that they may play an important role in the pathogenesis of atherosclerosis. Moreover, atherosclerotic lesions contain the Th1-type cytokine IFN-γ, a potentiator of atherosclerosis. The present study demonstrates the differential expression of the 3 IFN-γ–inducible CXC chemokines — IFN-inducible protein 10 (IP-10), monokine induced by IFN-γ (Mig), and IFN-inducible T-cell α chemoattractant (I-TAC) — by atheroma-associated cells, as well as the expression of their receptor, CXCR3, by all T lymphocytes within human atherosclerotic lesions in situ. Atheroma-associated endothelial cells (ECs), smooth muscle cells (SMCs), and macrophages (MØ) all expressed IP-10, whereas Mig and I-TAC were mainly expressed in ECs and MØ, as detected by double immunofluorescence staining. ECs of microvessels within lesions also expressed abundant I-TAC. In vitro experiments supported these results and showed that IL-1β, TNF-α, and CD40 ligand potentiated IP-10 expression from IFN-γ–stimulated ECs. In addition, nitric oxide (NO) treatment decreased IFN-γ induction of IP-10. Our findings suggest that the differential expression of IP-10, Mig, and I-TAC by atheroma-associated cells plays a role in the recruitment and retention of activated T lymphocytes observed within vascular wall lesions during atherogenesis. PMID:10525042

  8. Efficient sequence-specific isolation of DNA fragments and chromatin by in vitro enChIP technology using recombinant CRISPR ribonucleoproteins.

    PubMed

    Fujita, Toshitsugu; Yuno, Miyuki; Fujii, Hodaka

    2016-04-01

    The clustered regularly interspaced short palindromic repeats (CRISPR) system is widely used for various biological applications, including genome editing. We developed engineered DNA-binding molecule-mediated chromatin immunoprecipitation (enChIP) using CRISPR to isolate target genomic regions from cells for their biochemical characterization. In this study, we developed 'in vitro enChIP' using recombinant CRISPR ribonucleoproteins (RNPs) to isolate target genomic regions. in vitro enChIP has the great advantage over conventional enChIP of not requiring expression of CRISPR complexes in cells. We first showed that in vitro enChIP using recombinant CRISPR RNPs can be used to isolate target DNA from mixtures of purified DNA in a sequence-specific manner. In addition, we showed that this technology can be used to efficiently isolate target genomic regions, while retaining their intracellular molecular interactions, with negligible contamination from irrelevant genomic regions. Thus, in vitro enChIP technology is of potential use for sequence-specific isolation of DNA, as well as for identification of molecules interacting with genomic regions of interest in vivo in combination with downstream analysis. © 2016 The Authors. Genes to Cells published by Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

  9. Regional patterns of major nonnative invasive plants and associated factors in upper Midwest forests

    Treesearch

    Zhaofei Fan; W. Keith Moser; Mark H. Hansen; Mark D. Nelson

    2013-01-01

    Nonnative invasive plants (IPs) are rapidly spreading into natural ecosystems (e.g., forests and grasslands). Potential threats of IP invasion into natural ecosystems include biodiversity loss, structural and environmental change, habitat degradation, and economic losses. The Upper Midwest of the United States encompasses the states of Illinois, Indiana, Iowa, Michigan...

  10. Effect of surface acid etching on the biaxial flexural strength of two hot-pressed glass ceramics.

    PubMed

    Hooshmand, Tabassom; Parvizi, Shaghayegh; Keshvad, Alireza

    2008-07-01

    The purpose of this study was to assess the effect of surface acid etching on the biaxial flexural strength of two hot-pressed glass ceramics reinforced by leucite or lithium disilicate crystals. Forty glass ceramic disks (14-mm diameter, 2-mm thick) consisting of 20 leucite-based ceramic disks (IPS Empress) and 20 lithia disilicate-based ceramic (IPS Empress 2) were produced by hot-pressing technique. All specimens were polished and then cleaned ultrasonically in distilled water. Ten specimens of each ceramic group were then etched with 9% hydrofluoric (HF) acid gel for 2 minutes and cleaned ultrasonically again. The biaxial flexural strength was measured by the piston-on-three-ball test in a universal testing machine. Data based on ten specimens in each group were analyzed by two-way ANOVA (alpha= 0.05). Microstructure of ceramic surfaces before and after acid etching was also examined by a scanning electron microscope. The mean biaxial flexural strength values for each group tested were (in MPa): nonetched IPS Empress = 118.6 +/- 25.5; etched IPS Empress = 102.9 +/- 15.4; nonetched IPS Empress 2 = 283.0 +/- 48.5; and etched IPS Empress 2 = 250.6 +/- 34.6. The results showed that the etching process reduced the biaxial flexural strengths significantly for both ceramic types (p= 0.025). No significant interaction between the ceramic type and etching process was found (p= 0.407). From the results, it was concluded that surface HF acid etching could have a weakening effect on hot-pressed leucite or lithia disilicate-based glass ceramic systems.

  11. Efficient Generation of β-Globin-Expressing Erythroid Cells Using Stromal Cell-Derived Induced Pluripotent Stem Cells from Patients with Sickle Cell Disease.

    PubMed

    Uchida, Naoya; Haro-Mora, Juan J; Fujita, Atsushi; Lee, Duck-Yeon; Winkler, Thomas; Hsieh, Matthew M; Tisdale, John F

    2017-03-01

    Human embryonic stem (ES) cells and induced pluripotent stem (iPS) cells represent an ideal source for in vitro modeling of erythropoiesis and a potential alternative source for red blood cell transfusions. However, iPS cell-derived erythroid cells predominantly produce ε- and γ-globin without β-globin production. We recently demonstrated that ES cell-derived sacs (ES sacs), known to express hemangioblast markers, allow for efficient erythroid cell generation with β-globin production. In this study, we generated several iPS cell lines derived from bone marrow stromal cells (MSCs) and peripheral blood erythroid progenitors (EPs) from sickle cell disease patients, and evaluated hematopoietic stem/progenitor cell (HSPC) generation after iPS sac induction as well as subsequent erythroid differentiation. MSC-derived iPS sacs yielded greater amounts of immature hematopoietic progenitors (VEGFR2 + GPA-), definitive HSPCs (CD34 + CD45+), and megakaryoerythroid progenitors (GPA + CD41a+), as compared to EP-derived iPS sacs. Erythroid differentiation from MSC-derived iPS sacs resulted in greater amounts of erythroid cells (GPA+) and higher β-globin (and βS-globin) expression, comparable to ES sac-derived cells. These data demonstrate that human MSC-derived iPS sacs allow for more efficient erythroid cell generation with higher β-globin production, likely due to heightened emergence of immature progenitors. Our findings should be important for iPS cell-derived erythroid cell generation. Stem Cells 2017;35:586-596. © 2016 AlphaMed Press.

  12. Somatodendritic surface expression of epitope-tagged and KChIP binding-deficient Kv4.2 channels in hippocampal neurons.

    PubMed

    Prechtel, Helena; Hartmann, Sven; Minge, Daniel; Bähring, Robert

    2018-01-01

    Kv4.2 channels mediate a subthreshold-activating somatodendritic A-type current (ISA) in hippocampal neurons. We examined the role of accessory Kv channel interacting protein (KChIP) binding in somatodendritic surface expression and activity-dependent decrease in the availability of Kv4.2 channels. For this purpose we transfected cultured hippocampal neurons with cDNA coding for Kv4.2 wild-type (wt) or KChIP binding-deficient Kv4.2 mutants. All channels were equipped with an externally accessible hemagglutinin (HA)-tag and an EGFP-tag, which was attached to the C-terminal end. Combined analyses of EGFP self-fluorescence, surface HA immunostaining and patch-clamp recordings demonstrated similar dendritic trafficking and functional surface expression for Kv4.2[wt]HA,EGFP and the KChIP binding-deficient Kv4.2[A14K]HA,EGFP. Coexpression of exogenous KChIP2 augmented the surface expression of Kv4.2[wt]HA,EGFP but not Kv4.2[A14K]HA,EGFP. Notably, activity-dependent decrease in availability was more pronounced in Kv4.2[wt]HA,EGFP + KChIP2 coexpressing than in Kv4.2[A14K]HA,EGFP + KChIP2 coexpressing neurons. Our results do not support the notion that accessory KChIP binding is a prerequisite for dendritic trafficking and functional surface expression of Kv4.2 channels, however, accessory KChIP binding may play a potential role in Kv4.2 modulation during intrinsic plasticity processes.

  13. Plasma current ramp-up by lower hybrid wave using innovative antennas on TST-2

    NASA Astrophysics Data System (ADS)

    Takase, Yuichi; Ejiri, Akira; Moeller, Charles; Roidl, Benedikt; Shinya, Takahiro; Tsujii, Naoto; Yajima, Satoru; Yamazaki, Hibiki; Kitayama, Akichika; Matsumoto, Naoki; Sato, Akito; Sonehara, Masateru; Takahashi, Wataru; Tajiri, Yoshiyuki; Takei, Yuki; Togashi, Hiro; Toida, Kazuya; Yoshida, Yusuke

    2016-10-01

    Non-inductive plasma current (Ip) ramp-up by RF power in the lower hybrid frequency range is being studied on the TST-2 spherical tokamak (R = 0.36 m, a = 0.23 m, Bt = 0.3 T, Ip = 0.1 MA). Up to 400 kW of RF power is available at a frequency of 200 MHz. An innovative antenna called the capacitively-coupled combline (CCC) antenna was developed to excite a sharp, highly directional traveling wave with the electric field polarized in the toroidal direction. It is an array of resonant circuit elements made of capacitance and inductance, coupled to neighboring elements by mutual capacitance. Two CCC antennas are installed in TST-2, a 13-element outboard-launch antenna and a 6-element top-launch antenna. The latter was installed in March 2016 to improve accessibility to the core and to achieve single-pass damping. The suspected wave power loss in the scrape-off layer plasma should also be avoided. Ip ramp-up to 25 kA has been achieved so far. An upgrade of the Bt power supply is planned to take advantage of the observed improvement of Ip ramp-up with Bt. Higher Bt for longer pulses should improve the Ip ramp-up efficiency by improving wave accessibility and by reducing prompt orbit losses of energetic electrons.

  14. Pindolol potentiates the panicolytic effect of paroxetine in the elevated T-maze.

    PubMed

    Sela, Vânia R; Roncon, Camila M; Zangrossi, Hélio; Graeff, Frederico G; Audi, Elisabeth A

    2010-09-25

    the β-adrenergic and 5-HT(1A) receptor antagonist pindolol has been used in combination with antidepressant drugs, to shorten the time of onset of clinical efficacy and/or increase the proportion of responders in depressive and anxiety disorders. The aim of this study was to examine the interaction between pindolol and the selective serotonin reuptake inhibitor (SSRI), paroxetine in rats submitted to the elevated T-maze (ETM). for assessing the drug combination effect, rats were administered with pindolol before paroxetine, using oral or intraperitoneal (i.p.) routes of acute administration, and were submitted to the ETM model. the highest dose of pindolol used (15.0mg/kg, i.p.) increased both inhibitory avoidance and escape latencies in the ETM, probably due to nonspecific motor deficit, since locomotion in a circular arena was also significantly decreased. The highest dose of paroxetine (3.0mg/kg, i.p.) selectively impaired escape, considered a panicolytic effect. Combination of pindolol (5.0mg/kg, i.p.) with an ineffective dose of paroxetine (1.5mg/kg, i.p.) impaired escape, indicating a potentiation of the panicolytic effect of paroxetine. By the oral route, neither paroxetine (3.0mg/kg) nor pindolol (5.0mg/kg) alone were effective, but the combination treatment had a marked panicolytic effect, again indicating drug potentiation. the present results show that the combination of the ineffective doses of pindolol and paroxetine significantly increased escape latency, indicating a selective panicolytic effect. These findings give preclinical support for the use of this drug combination in the treatment of panic disorder (PD). 2010 Elsevier Inc. All rights reserved.

  15. Computer Networks and Networking: A Primer.

    ERIC Educational Resources Information Center

    Collins, Mauri P.

    1993-01-01

    Provides a basic introduction to computer networks and networking terminology. Topics addressed include modems; the Internet; TCP/IP (Transmission Control Protocol/Internet Protocol); transmission lines; Internet Protocol numbers; network traffic; Fidonet; file transfer protocol (FTP); TELNET; electronic mail; discussion groups; LISTSERV; USENET;…

  16. Inoculum Potential of Fusarium spp. Relates to Tillage and Straw Management in Norwegian Fields of Spring Oats

    PubMed Central

    Hofgaard, Ingerd S.; Seehusen, Till; Aamot, Heidi U.; Riley, Hugh; Razzaghian, Jafar; Le, Vinh H.; Hjelkrem, Anne-Grete R.; Dill-Macky, Ruth; Brodal, Guro

    2016-01-01

    The increased occurrence of Fusarium-mycotoxins in Norwegian cereals over the last decade, is thought to be caused by increased inoculum resulting from more cereal residues at the soil surface as a result of reduced tillage practices. In addition, weather conditions have increasingly promoted inoculum development and infection by Fusarium species. The objective of this work was to elucidate the influence of different tillage regimes (autumn plowing; autumn harrowing; spring plowing; spring harrowing) on the inoculum potential (IP) and dispersal of Fusarium spp. in spring oats. Tillage trials were conducted at two different locations in southeast Norway from 2010 to 2012. Oat residues from the previous year’s crop were collected within a week after sowing for evaluation. IP was calculated as the percentage of residues infested with Fusarium spp. multiplied by the proportion of the soil surface covered with residues. Fusarium avenaceum and F. graminearum were the most common Fusarium species recovered from oat residues. The IP of Fusarium spp. was significantly lower in plowed plots compared to those that were harrowed. Plowing in either the autumn or spring resulted in a low IP. Harrowing in autumn was more effective in reducing IP than the spring harrowing, and IP levels for the spring harrowed treatments were generally higher than all other tillage treatments examined. Surprisingly low levels of F. langsethiae were detected in the residues, although this species is a common pathogen of oat in Norway. The percentage of the residues infested with F. avenaceum, F. graminearum, F. culmorum, and F. langsethiae generally related to the quantity of DNA of the respective Fusarium species determined using quantitative PCR (qPCR). Fusarium dispersal, quantified by qPCR analysis of spore trap samples collected at and after heading, generally corresponded to the IP. Fusarium dispersal was also observed to increase after rainy periods. Our findings are in line with the general understanding that plowing is a means to reduce the IP of Fusarium spp. in cereal fields. The main inoculum source for F. langsethiae remains unclear. Our results will be useful in the development of forecasting tools to calculate the risk of Fusarium in cereals. PMID:27148236

  17. Guanosine may increase absence epileptic activity by means of A2A adenosine receptors in Wistar Albino Glaxo Rijswijk rats.

    PubMed

    Lakatos, Renáta Krisztina; Dobolyi, Árpád; Todorov, Mihail Ivilinov; Kékesi, Katalin A; Juhász, Gábor; Aleksza, Magdolna; Kovács, Zsolt

    2016-06-01

    The non-adenosine nucleoside guanosine (Guo) was demonstrated to decrease quinolinic acid(QA)-induced seizures, spontaneously emerged absence epileptic seizures and lipopolysaccharide(LPS)-evoked induction of absence epileptic seizures suggesting its antiepileptic potential. It was also described previously that intraperitoneal (i.p.) injection of 20 and 50mg/kg Guo decreased the number of spike-wave discharges (SWDs) in a well investigated model of human absence epilepsy, the Wistar Albino Glaxo Rijswijk (WAG/Rij) rats during 4th (20mg/kg Guo) and 3rd as well as 4th (50mg/kg Guo) measuring hours. Guanosine can potentially decrease SWD number by means of its putative receptors but absence epileptic activity changing effects of Guo by means of increased extracellular adenosine (Ado) cannot be excluded. An increase in the dose of i.p. injected Guo is limited by its low solubility in saline, therefore, we addressed in the present study whether higher doses of Guo, diluted in sodium hydroxide (NaOH) solution, have more potent antiepileptic effect in WAG/Rij rats. We confirmed that i.p. 50mg/kg Guo decreased but, surprisingly, i.p. 100mg/kg Guo enhanced the number of SWDs in WAG/Rij rats. Combined i.p. injection of a non-selective Ado receptor antagonist theophylline (5mg/kg) or a selective Ado A2A receptor (A2AR) antagonist SCH 58261 (7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidine) (1mg/kg) and a cyclooxygenase 1 and 2/COX-1 and COX-2 inhibitor indomethacin (10mg/kg) with 100mg/kg Guo decreased the SWD number compared to i.p. 100mg/kg Guo alone. The results suggest that i.p. 100mg/kg Guo can increase SWD number by means of the adenosinergic system. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Differential contributions to the interception of occluded ballistic trajectories by the temporoparietal junction, area hMT/V5+, and the intraparietal cortex.

    PubMed

    Delle Monache, Sergio; Lacquaniti, Francesco; Bosco, Gianfranco

    2017-09-01

    The ability to catch objects when transiently occluded from view suggests their motion can be extrapolated. Intraparietal cortex (IPS) plays a major role in this process along with other brain structures, depending on the task. For example, interception of objects under Earth's gravity effects may depend on time-to-contact predictions derived from integration of visual signals processed by hMT/V5+ with a priori knowledge of gravity residing in the temporoparietal junction (TPJ). To investigate this issue further, we disrupted TPJ, hMT/V5+, and IPS activities with transcranial magnetic stimulation (TMS) while subjects intercepted computer-simulated projectile trajectories perturbed randomly with either hypo- or hypergravity effects. In experiment 1 , trajectories were occluded either 750 or 1,250 ms before landing. Three subject groups underwent triple-pulse TMS (tpTMS, 3 pulses at 10 Hz) on one target area (TPJ | hMT/V5+ | IPS) and on the vertex (control site), timed at either trajectory perturbation or occlusion. In experiment 2 , trajectories were entirely visible and participants received tpTMS on TPJ and hMT/V5+ with same timing as experiment 1 tpTMS of TPJ, hMT/V5+, and IPS affected differently the interceptive timing. TPJ stimulation affected preferentially responses to 1-g motion, hMT/V5+ all response types, and IPS stimulation induced opposite effects on 0-g and 2-g responses, being ineffective on 1-g responses. Only IPS stimulation was effective when applied after target disappearance, implying this area might elaborate memory representations of occluded target motion. Results are compatible with the idea that IPS, TPJ, and hMT/V5+ contribute to distinct aspects of visual motion extrapolation, perhaps through parallel processing. NEW & NOTEWORTHY Visual extrapolation represents a potential neural solution to afford motor interactions with the environment in the face of missing information. We investigated relative contributions by temporoparietal junction (TPJ), hMT/V5+, and intraparietal cortex (IPS), cortical areas potentially involved in these processes. Parallel organization of visual extrapolation processes emerged with respect to the target's motion causal nature: TPJ was primarily involved for visual motion congruent with gravity effects, IPS for arbitrary visual motion, whereas hMT/V5+ contributed at earlier processing stages. Copyright © 2017 the American Physiological Society.

  19. A comparative DFT study on the antioxidant activity of apigenin and scutellarein flavonoid compounds

    NASA Astrophysics Data System (ADS)

    Sadasivam, K.; Kumaresan, R.

    2011-03-01

    The potent antioxidant activity of flavonoids relevant to their ability to scavenge reactive oxygen species is the most important function of flavonoids. Density functional theory calculations were explored to investigate the antioxidant activity of flavonoid compounds such as apigenin and scutellarein. The biological characteristics are dependent on electronic parameters, describing the charge distribution on the rings of the flavonoid molecules. The computation of structural and various molecular descriptors such as polarizability, dipole moment, energy gap, homolytic O-H bond dissociation enthalpies (BDEs), ionization potential (IP), electron affinity, hardness, softness, electronegativity, electrophilic index and density plot of molecular orbital for neutral as well as radical species were carried out and studied. The B3LYP/6-311G(d,p) basis set was adopted for all the computations. This computation reveals that scutellarein exhibits higher degree of antioxidant activity than apigenin. Their dipole moment and polarizability analysis show that both the compounds are polar in nature and have the capacity to polarize other atoms.

  20. Total Electron Content forecast model over Australia

    NASA Astrophysics Data System (ADS)

    Bouya, Zahra; Terkildsen, Michael; Francis, Matthew

    Ionospheric perturbations can cause serious propagation errors in modern radio systems such as Global Navigation Satellite Systems (GNSS). Forecasting ionospheric parameters is helpful to estimate potential degradation of the performance of these systems. Our purpose is to establish an Australian Regional Total Electron Content (TEC) forecast model at IPS. In this work we present an approach based on the combined use of the Principal Component Analysis (PCA) and Artificial Neural Network (ANN) to predict future TEC values. PCA is used to reduce the dimensionality of the original TEC data by mapping it into its eigen-space. In this process the top- 5 eigenvectors are chosen to reflect the directions of the maximum variability. An ANN approach was then used for the multicomponent prediction. We outline the design of the ANN model with its parameters. A number of activation functions along with different spectral ranges and different numbers of Principal Components (PCs) were tested to find the PCA-ANN models reaching the best results. Keywords: GNSS, Space Weather, Regional, Forecast, PCA, ANN.

  1. Accessibility of insulin pumps for blind and visually impaired people.

    PubMed

    Uslan, Mark M; Burton, Darren M; Chertow, Bruce S; Collins, Ronda

    2004-10-01

    Continuous subcutaneous insulin infusion using an insulin pump (IP) more closely mimics the normal pancreas than multiple insulin injections. It is an effective, and often a preferred, means of maintaining normal blood glucose levels, but IPs were not designed to be fully accessible to blind or visually impaired people. This study will identify accessibility issues related to the design of IPs and focus on the key improvements required in the user interface to provide access for people who are blind or visually impaired. IPs that are commercially available were evaluated, and features and functions such as operating procedures, user interface design, and user manuals were tabulated and analyzed. Potential failures and design priorities were identified through a Failure Modes and Effects Analysis (FMEA). Although the IPs do provide some limited audio output, in general, it was found to be of minimal use to people who are blind or visually impaired. None of the IPs uses high-contrast displays with consistently large fonts preferred by people who are visually impaired. User manuals were also found to be of minimal use. Results of the FMEA emphasize the need to focus design improvements on communicating and verifying information so that errors and failures can be detected and corrected. The most important recommendation for future IP development is speech output capability, which, more than any other improvement, would break down accessibility barriers and allow blind and visually impaired people to take advantage of the benefits of IP technology.

  2. The cooked meat-derived mammary carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine promotes invasive behaviour of breast cancer cells.

    PubMed

    Lauber, Sandra N; Gooderham, Nigel J

    2011-01-11

    The cooked meat derived genotoxic carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) induces cancer of the colon, prostate and mammary gland when fed to rats. Epidemiology studies link these tumours to a Western diet and exposure to heterocyclic amines such as PhIP. We have shown that PhIP is also potently estrogenic and have proposed that this hormonal activity contributes to its target site carcinogenicity. We now postulate that the estrogenic properties of PhIP influence metastatic potential. We have used an in vitro assay for cell invasion based upon digestion and migration through a reconstituted basement membrane model. Zymography and immunoblotting were used to confirm PhIP-mediated changes associated with induction of the invasive phenotype. Treatment of the mammary cancer cell lines MCF-7 and T47D with PhIP induces cells to digest and migrate through a reconstituted basement membrane. The response was dose dependent, observed at sub-nanomolar concentrations of PhIP and was inhibited by the antiestrogen ICI 182,780. The PhIP-induced invasive phenotype was associated with expression of cathepsin D, cyclooxygenase-2 and matrix metalloproteinase activity. These findings emphasise the range and potency of the biological activities associated with this cooked meat product and mechanistically support the tissue-specific carcinogenicity of the chemical. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  3. Arl6IP1 has the ability to shape the mammalian ER membrane in a reticulon-like fashion.

    PubMed

    Yamamoto, Yasunori; Yoshida, Asuka; Miyazaki, Naoyuki; Iwasaki, Kenji; Sakisaka, Toshiaki

    2014-02-15

    The ER (endoplasmic reticulum) consists of the nuclear envelope and a peripheral network of membrane sheets and tubules. Two classes of the evolutionarily conserved ER membrane proteins, reticulons and REEPs (receptor expression-enhancing proteins)/DP1 (deleted in polyposis locus 1)/Yop1 (YIP 1 partner), shape high-curvature ER tubules. In mammals, four members of the reticulon family and six members of the REEP family have been identified so far. In the present paper we report that Arl6IP1(ADP-ribosylation factor-like 6 interacting protein 1), an anti-apoptotic protein specific to multicellular organisms, is a potential player in shaping the ER tubules in mammalian cells. Arl6IP1, which does not share an overall primary sequence homology with reticulons, harbours reticulon-like short hairpin transmembrane domains and binds to atlastin, a GTPase that mediates the formation of the tubular ER network. Overexpression of Arl6IP1 induced extensive tubular structures of the ER and excluded a luminal protein. Furthermore, overexpression of Arl6IP1 stabilized the ER tubules, allowing the cells to maintain the ER tubules even in the absence of microtubules. Arl6IP1 constricted liposomes into tubules. The short hairpin structures of the transmembrane domains were required for the membrane-shaping activity of Arl6IP1. The results of the present study indicate that Arl6IP1 has the ability to shape high-curvature ER tubules in a reticulon-like fashion.

  4. Overcoming communication challenges in integrative supportive cancer care: The integrative physician, the psycho-oncologist, and the patient.

    PubMed

    Ben-Arye, Eran; Shavit, Efrat; Wiental, Haya; Schiff, Elad; Agour, Olga; Samuels, Noah

    2016-12-01

    Complementary/integrative medicine (CIM) services are increasingly being integrated into conventional supportive cancer care, presenting a number of challenges to communication between healthcare professionals (HCPs). The purpose of the present study was to explore the impact of the communication between integrative physicians (IPs) trained in CIM and social workers (SWs) working as psycho-oncologists in the same oncology setting. We examine whether IP-SW communication correlates with the number of patient-SW sessions, as provided within the oncology department. SW-IP communication, defined as a summary of the IP consultation sent to the patient's SW, was compared to SW-patient communication, defined as the number of psycho-oncology treatment sessions. Of 344 patients referred by their oncology HCP for IP consultation, 91 were referred by an SW and 253 by an oncologist or nurse. IP-to-SW summaries were provided for 150 patients referred by a non-SW HCP (43.6%), and for 91 of SW-referred patients (26.5%). In all, 32 patients referred to the IP had no psycho-oncology interaction with an SW; 58 only one meeting; and 254 with ≥2 interactions, with 119 having >6 sessions. SW-patient interactions were greater with higher rates of IP-SW communication, for both patients referred by an SW (79.1%) and those referred by a non-SW HCP (77.3%) when compared to patients for whom no summary was provided (64.1%; p= 0.02). A greater level of IP-SW communication, measured by the provision of an IP summary to the patient's SW, was found to correlate with a higher rate of SW-patient interactions. The use of a structured two-way referral-summary between IPs and SWs has the potential to advance the SW-patient psycho-oncology interaction, within an integrative supportive cancer care setting. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Faster in-plane switching and reduced rotational viscosity characteristics in a graphene-nematic suspension

    NASA Astrophysics Data System (ADS)

    Basu, Rajratan; Kinnamon, Daniel; Skaggs, Nicole; Womack, James

    2016-05-01

    The in-plane switching (IPS) for a nematic liquid crystal (LC) was found to be considerably faster when the LC was doped with dilute concentrations of monolayer graphene flakes. Additional studies revealed that the presence of graphene reduced the rotational viscosity of the LC, permitting the nematic director to respond quicker in IPS mode on turning the electric field on. The studies were carried out with several graphene concentrations in the LC, and the experimental results coherently suggest that there exists an optimal concentration of graphene, allowing a reduction in the IPS response time and rotational viscosity in the LC. Above this optimal graphene concentration, the rotational viscosity was found to increase, and consequently, the LC no longer switched faster in IPS mode. The presence of graphene suspension was also found to decrease the LC's pretilt angle significantly due to the π-π electron stacking between the LC molecules and graphene flakes. To understand the π-π stacking interaction, the anchoring mechanism of the LC on a CVD grown monolayer graphene film on copper substrate was studied by reflected crossed polarized microscopy. Optical microphotographs revealed that the LC alignment direction depended on monolayer graphene's hexagonal crystal structure and its orientation.

  6. Rearing-environment-dependent hippocampal local field potential differences in wild-type and inositol trisphosphate receptor type 2 knockout mice.

    PubMed

    Tanaka, Mika; Wang, Xiaowen; Mikoshiba, Katsuhiko; Hirase, Hajime; Shinohara, Yoshiaki

    2017-10-15

    Mice reared in an enriched environment are demonstrated to have larger hippocampal gamma oscillations than those reared in isolation, thereby confirming previous observations in rats. To test whether astrocytic Ca 2+ surges are involved in this experience-dependent LFP pattern modulation, we used inositol trisphosphate receptor type 2 (IP 3 R2)-knockout (KO) mice, in which IP 3 /Ca 2+ signalling in astrocytes is largely diminished. We found that this experience-dependent gamma power alteration persists in the KO mice. Interestingly, hippocampal ripple events, the synchronized events critical for memory consolidation, are reduced in magnitude and frequency by both isolated rearing and IP 3 R2 deficiency. Rearing in an enriched environment (ENR) is known to enhance cognitive and memory abilities in rodents, whereas social isolation (ISO) induces depression-like behaviour. The hippocampus has been documented to undergo morphological and functional changes depending on these rearing environments. For example, rearing condition during juvenility alters CA1 stratum radiatum gamma oscillation power in rats. In the present study, hippocampal CA1 local field potentials (LFP) were recorded from bilateral CA1 in urethane-anaesthetized mice that were reared in either an ENR or ISO condition. Similar to previous findings in rats, gamma oscillation power during theta states was higher in the ENR group. Ripple events that occur during non-theta periods in the CA1 stratum pyramidale also had longer intervals in ISO mice. Because astrocytic Ca 2+ elevations play a key role in synaptic plasticity, we next tested whether these changes in LFP are also expressed in inositol trisphosphate receptor type 2 (IP 3 R2)-knockout (KO) mice, in which astrocytic Ca 2+ elevations are largely diminished. We found that the gamma power was also higher in IP 3 R2-KO-ENR mice compared to IP 3 R2-KO-ISO mice, suggesting that the rearing-environment-dependent gamma power alteration does not necessarily require the astrocytic IP 3 /Ca 2+ pathway. By contrast, ripple events showed genotype-dependent changes, as well as rearing condition-dependent changes: ISO housing and IP 3 R2 deficiency both lead to longer inter-ripple intervals. Moreover, we found that ripple magnitude in the right CA1 tended to be smaller in IP 3 R2-KO. Because IP 3 R2-KO mice have been reported to have depression phenotypes, our results suggest that ripple events and the mood of animals may be broadly correlated. © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

  7. Introduction of Exogenous HSV-TK Suicide Gene Increases Safety of Keratinocyte-Derived Induced Pluripotent Stem Cells by Providing Genetic "Emergency Exit" Switch.

    PubMed

    Sułkowski, Maciej; Konieczny, Paweł; Chlebanowska, Paula; Majka, Marcin

    2018-01-09

    Since their invention in 2006, induced Pluripotent Stem (iPS) cells remain a great promise for regenerative medicine circumventing the ethical issues linked to Embryonic Stem (ES) cell research. iPS cells can be generated in a patient-specific manner as an unlimited source of various cell types for in vitro drug screening, developmental biology studies and regenerative use. Having the capacity of differentiating into the cells of all three primary germ layers, iPS cells have high potential to form teratoma tumors. This remains their main disadvantage and hazard which, until resolved, prevents utilization of iPS cells in clinic. Here, we present an approach for increasing iPS cells safety by introducing genetic modification-exogenous suicide gene Herpes Simplex Virus Thymidine Kinase ( HSV-TK ). Its expression results in specific vulnerability of genetically modified cells to prodrug-ganciclovir (GCV). We show that HSV-TK expressing cells can be eradicated both in vitro and in vivo with high specificity and efficiency with low doses of GCV. Described strategy increases iPS cells safety for future clinical applications by generating "emergency exit" switch allowing eradication of transplanted cells in case of their malfunction.

  8. Quality improvement collaborative: A novel approach to improve infection prevention and control. Perceptions of lead infection prevention nurses who participated.

    PubMed

    Adams, Debra; Hine, Victoria; Bucior, Helen; Foster, Wendy; Mukombe, Nyarayi; Ryan, Jane; Smirthwaite, Sandra; Winfield, Jodie

    2018-03-01

    In response to the ongoing infection prevention (IP) challenges in England, a 90-day quality improvement (QI) collaborative programme was developed. The paper discusses the approach, benefits, challenges and evaluation of the programme. The objective of the collaborative was to develop new approaches to enable sustainable and effective IP. Six trusts in the region participated in the collaborative. Each defined their bespoke IP focus. There was no expectation that statistically significant measurable improvements would be identified during the short time frame. The experiences of the participants were sought both during the programme to facilitate its constant review and at the end of the programme to evaluate its effectiveness. The feedback focused on achievements, barriers to change and benefits of participating in a QI collaborative. To measure the potential success of the projects, participants completed the Model for Understanding Success in Quality framework. (MUSIQ; Kaplan et al., 2012). Since each trusts IP focus was bespoke commonalities of success were not evaluated. Participants identified a positive outcome from their QI interventions. The MUSIQ score identified the projects had the potential for success. The feedback from the participants demonstrated that it is worthy of further development.

  9. Interplanetary scintillation observations with the Cocoa Cross radio telescope

    NASA Technical Reports Server (NTRS)

    Cronyn, W. M.; Shawhan, S. D.; Erskine, F. T.; Huneke, A. H.; Mitchell, D. G.

    1976-01-01

    Physical and electrical parameters for the 34.3-MHz Cocoa Cross radio telescope are given. The telescope is dedicated to the determination of solar-wind characteristics in and out of the ecliptic plane through measurement of electron-density irregularity structure as determined from IPS (interplanetary scintillation) of natural radio sources. The collecting area (72,000 sq m), angular resolution (0.4 deg EW by 0.6 deg NS), and spatial extent (1.3 km EW by 0.8 km NS) make the telescope well suited for measurements of IPS index and frequency scale for hundreds of weak radio sources without serious confusion effects.

  10. Excited states of aniline by photoabsorption spectroscopy in the 30,000-90,000 cm(-1) region using synchrotron radiation.

    PubMed

    Rajasekhar, B N; Veeraiah, A; Sunanda, K; Jagatap, B N

    2013-08-14

    The photoabsorption spectrum of aniline (C6H5NH2) in gas phase in the 30,000-90,000 cm(-1) (3.7-11.2 eV) region is recorded at resolution limit of 0.008 eV using synchrotron radiation source for the first time to comprehend the nature of the excited valence and Rydberg states. The first half of the energy interval constitutes the richly structured valence transitions from the ground to excited states up to the first ionization potential (IP) at 8.02 eV. The spectrum in the second half consists of vibrational features up to second IP (9.12 eV) and structureless broad continuum up to the third IP (10.78 eV). The electronic states are assigned mainly to the singlets belonging to π → π* transitions. A few weak initial members of Rydberg states arising from π → 4s, np or nd transitions are also identified. Observed vibrational features are assigned to transitions from the ground state A' to the excited states 1A", 3A', 5A", 6A', and 10A" in C(s) symmetry. Time dependent density functional theory (TDDFT) calculations at B3LYP level of theory are employed to obtain the vertical excitation energies and the symmetries of the excited states in equilibrium configuration. The computed values of the transition energies agree fairly well with the experimental data. Further the calculated oscillator strengths are used to substantiate the assignments of the bands. The work provides a comprehensive picture of the vacuum ultraviolet photoabsorption spectrum of aniline up to its third ionization limit.

  11. The Trans Pacific Partnership Agreement and access to HIV treatment in Vietnam.

    PubMed

    Moir, Hazel V J; Tenni, Brigitte; Gleeson, Deborah; Lopert, Ruth

    2018-04-01

    In the Trans Pacific Partnership (TPP) Agreement negotiations, the USA successfully pursued intellectual property (IP) provisions that will affect the affordability of medicines, including anti-retrovirals (ARV) for HIV. Vietnam has the lowest GDP per capita of the 12 TPP countries and in 2013 provided ARVs for only 68% of eligible people living with HIV. Using the current Vietnamese IP regime as our base case, we analysed the potential impact of a regime making full use of legal IP flexibilities, and one based on the IP provisions of the final, agreed TPP text. Results indicate that at current funding levels 82% of Vietnam's eligible people living with HIV would receive ARVs if legal flexibilities were fully utilised, while as few as 30% may have access to ARVs under the TPP Agreement - more than halving the proportion currently treated.

  12. Human induced pluripotent stem cells: a review of the US patent landscape.

    PubMed

    Georgieva, Bilyana P; Love, Jane M

    2010-07-01

    Human induced pluripotent stem (iPS) cells and human embryonic stem cells are cells that have the ability to differentiate into a variety of cell types. Embryonic stem cells are derived from human embryos; however, by contrast, human iPS cells can be obtained from somatic cells that have undergone a process of 'reprogramming' via genetic manipulation such that they develop pluripotency. Since iPS cells are not derived from human embryos, they are a less complicated source of human pluripotent cells and are considered valuable research tools and potentially useful in therapeutic applications in regenerative medicine. Worldwide, there are only three issued patents concerning iPS cells. Therefore, the patent landscape in this field is largely undefined. This article provides an overview of the issued patents as well as the pending published patent applications in the field.

  13. A fresh look at the photoelectron spectrum of bromobenzene: A third-order non-Dyson electron propagator study.

    PubMed

    Schneider, M; Soshnikov, D Yu; Holland, D M P; Powis, I; Antonsson, E; Patanen, M; Nicolas, C; Miron, C; Wormit, M; Dreuw, A; Trofimov, A B

    2015-10-14

    The valence-shell ionization spectrum of bromobenzene, as a representative halogen substituted aromatic, was studied using the non-Dyson third-order algebraic-diagrammatic construction [nD-ADC(3)] approximation for the electron propagator. This method, also referred to as IP-ADC(3), was implemented as a part of the Q-Chem program and enables large-scale calculations of the ionization spectra, where the computational effort scales as n(5) with respect to the number of molecular orbitals n. The IP-ADC(3) scheme is ideally suited for investigating low-lying ionization transitions, so fresh insight could be gained into the cationic state manifold of bromobenzene. In particular, the present IP-ADC(3) calculations with the cc-pVTZ basis reveal a whole class of low-lying low-intensity two-hole-one-particle (2h-1p) doublet and quartet states, which are relevant to various photoionization processes. The good qualitative agreement between the theoretical spectral profile for the valence-shell ionization transitions generated with the smaller cc-pVDZ basis set and the experimental photoelectron spectrum measured at a photon energy of 80 eV on the PLÉIADES beamline at the Soleil synchrotron radiation source allowed all the main features to be assigned. Some theoretical aspects of the ionization energy calculations concerning the use of various approximation schemes and basis sets are discussed.

  14. Non-solenoidal Startup via Local Helicity Injection on Pegasus: Progress and Plans

    NASA Astrophysics Data System (ADS)

    Reusch, J. A.; Barr, J. L.; Bodner, G. M.; Bongard, M. W.; Burke, M. G.; Fonck, R. J.; Hinson, E. T.; Lewicki, B. T.; Perry, J. M.; Schlossberg, D. J.

    2015-11-01

    Non-solenoidal plasma startup via local helicity injection (LHI) at the Pegasus toroidal experiment now provides routine operation at Ip ~ 0.17MA with Iinj ~ 5kA and Vinj ~ 1kV from four active arc injectors. Experiments in the past year have advanced the understanding of the governing physics of LHI and its supporting technology. Injector impedance scales as Vinj3/ 2 and is governed by two effects: a quasineutrality constraint on electron beam propagation, related to the tokamak edge density, and double-layer sheath expansion, related to narc. Injector design improvements permit operation at Vinj >= 1 kV without deleterious PMI or impurity generation. Discharges with varied shape, Ip(t), and helicity input test a predictive 0D power-balance model for LHI startup. Anomalous, reconnection-driven Ti >800 eV and strong MHD activity localized near the injectors are observed during LHI. Preliminary core Thomson scattering measurements indicate surprisingly high Te >300 eV, which if verified may indicate the dominance of high-energy electron fueling from the injector current streams. A new divertor injector system has been designed to substantially increase the available helicity input rate and support critical studies of confinement during LHI and reconnection activity at high Ip. A proposed upgrade to the Pegasus experiment will extend these studies to NSTX-U relevant parameters. Support: US DOE grants DE-FG02-96ER54375; and DE-SC0006928.

  15. A fresh look at the photoelectron spectrum of bromobenzene: A third-order non-Dyson electron propagator study

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

    Schneider, M.; Wormit, M.; Dreuw, A.

    2015-10-14

    The valence-shell ionization spectrum of bromobenzene, as a representative halogen substituted aromatic, was studied using the non-Dyson third-order algebraic-diagrammatic construction [nD-ADC(3)] approximation for the electron propagator. This method, also referred to as IP-ADC(3), was implemented as a part of the Q-Chem program and enables large-scale calculations of the ionization spectra, where the computational effort scales as n{sup 5} with respect to the number of molecular orbitals n. The IP-ADC(3) scheme is ideally suited for investigating low-lying ionization transitions, so fresh insight could be gained into the cationic state manifold of bromobenzene. In particular, the present IP-ADC(3) calculations with the cc-pVTZmore » basis reveal a whole class of low-lying low-intensity two-hole-one-particle (2h-1p) doublet and quartet states, which are relevant to various photoionization processes. The good qualitative agreement between the theoretical spectral profile for the valence-shell ionization transitions generated with the smaller cc-pVDZ basis set and the experimental photoelectron spectrum measured at a photon energy of 80 eV on the PLÉIADES beamline at the Soleil synchrotron radiation source allowed all the main features to be assigned. Some theoretical aspects of the ionization energy calculations concerning the use of various approximation schemes and basis sets are discussed.« less

  16. Positronium formation at Si surfaces

    NASA Astrophysics Data System (ADS)

    Kawasuso, A.; Maekawa, M.; Miyashita, A.; Wada, K.; Kaiwa, T.; Nagashima, Y.

    2018-06-01

    Positronium formation at Si(111) and Si(001) surfaces has been investigated by changing the doping level systematically over the range 300-1000 K. The temperature dependence of the positronium fraction varied with the doping condition, and there were practically no differences between the two surface orientations. In heavily doped n -type Si (n ≳1018cm-3) , the positronium fraction (IPs) increased above 700 K and reached more than 95% at 1000 K. In undoped and lightly doped Si (n , p ≲1015cm-3 ), IPs decreased from 300 to 500 K and increased above 700 K. In heavily doped p -type Si (p ≳1018cm-3 ), IPs increased in two steps: one at 500-600 K and one above 700 K. Overall, the positronium fraction increased with the amount of n -type doping. These phenomena were found to be dominated by two kinds of positronium with energies of 0.6-1.5 eV and 0.1-0.2 eV, which were attributed to the work-function mechanism and the surface-positron-mediated process, respectively, with contributions from conduction electrons. The positron work function was estimated to be positive. This agrees with first-principles calculation. The positive positron work function implies that the formation of excitonic electron-positron bound states begins in the bulk subsurface region and transits to the final positronium state in the vacuum.

  17. Cracking of porcelain surfaces arising from abrasive grinding with a dental air turbine.

    PubMed

    Chang, Chee W; Waddell, J Neil; Lyons, Karl M; Swain, Michael V

    2011-12-01

    The purpose of this in vitro study was to evaluate porcelain cracking induced by abrasive grinding with a conventional dental air turbine and abrasive diamond burs. Four commercially available porcelains were examined-Wieland ALLUX, Wieland ZIROX, IPS e.max Ceram, and IPS Empress Esthetic Veneering porcelain. Sixty discs of each porcelain type were fabricated according to manufacturer instructions, followed by an auto-glaze cycle. Abrasive grinding using fine, extra-fine, and ultra-fine diamond burs was carried out, using a conventional dental air turbine. The grinding parameters were standardized with regard to the magnitude of the force applied, rotational speed of the diamond bur, and flow rate of the water coolant. A testing apparatus was used to control the magnitude of force applied during the grinding procedure. The ground surfaces were then examined under scanning electron microscope. Cracking was seen for all porcelain types when ground with the fine bur. Cracking was not seen for specimens ground with the extra-fine or the ultra-fine bur. Wet abrasive grinding with a conventional dental air turbine and fine grit diamond burs has the potential to cause cracking in the four porcelain types tested. Similar abrasive grinding with smaller grit size particles does not cause similar observable cracking. © 2011 by the American College of Prosthodontists.

  18. Blocking adenylyl cyclase inhibits olfactory generator currents induced by "IP(3)-odors".

    PubMed

    Chen, S; Lane, A P; Bock, R; Leinders-Zufall, T; Zufall, F

    2000-07-01

    Vertebrate olfactory receptor neurons (ORNs) transduce odor stimuli into electrical signals by means of an adenylyl cyclase/cAMP second messenger cascade, but it remains widely debated whether this cAMP cascade mediates transduction for all odorants or only certain odor classes. To address this problem, we have analyzed the generator currents induced by odors that failed to produce cAMP in previous biochemical assays but instead produced IP(3) ("IP(3)-odors"). We show that in single salamander ORNs, sensory responses to "cAMP-odors" and IP(3)-odors are not mutually exclusive but coexist in the same cells. The currents induced by IP(3)-odors exhibit identical biophysical properties as those induced by cAMP odors or direct activation of the cAMP cascade. By disrupting adenylyl cyclase to block cAMP formation using two potent antagonists of adenylyl cyclase, SQ22536 and MDL12330A, we show that this molecular step is necessary for the transduction of both odor classes. To assess whether these results are also applicable to mammals, we examine the electrophysiological responses to IP(3)-odors in intact mouse main olfactory epithelium (MOE) by recording field potentials. The results show that inhibition of adenylyl cyclase prevents EOG responses to both odor classes in mouse MOE, even when "hot spots" with heightened sensitivity to IP(3)-odors are examined.

  19. cDNA cloning and characterization of a novel gene encoding the MLF1-interacting protein MLF1IP.

    PubMed

    Hanissian, Silva H; Akbar, Umar; Teng, Bin; Janjetovic, Zorica; Hoffmann, Anne; Hitzler, Johann K; Iscove, Norman; Hamre, Kristin; Du, Xiaoping; Tong, Yiai; Mukatira, Suraj; Robertson, Jon H; Morris, Stephan W

    2004-04-29

    Myelodysplasia/acute myeloid leukemia (MDS/AML) is characterized by a t(3;5)(q25.1;q34) chromosomal translocation that forms a fusion gene between nucleophosmin (NPM) and MDS/myeloid leukemia factor 1 (MLF1). We identified a novel protein, MLF1-interacting protein (MLF1IP), that specifically associates with MLF1 by yeast two-hybrid analysis and in pulldown assays, and colocalizes with it in both the nuclei and cytoplasm of cells. The MLF1IP gene locus is at chromosome 4q35.1 and is composed of 14 exons spanning 75.8 kb of genomic DNA. The MLF1IP cDNA encodes a 46-kDa protein that contains two bipartite and two classical nuclear localization signals, two nuclear receptor-binding motifs (LXXLL), two leucine zippers, two PEST residues and several potential phosphorylation sites. MLF1IP transcripts are expressed in a variety of tissues (e.g. fetal liver, bone marrow, thymus and testis). MLF1IP appears to be a lineage-specific gene whose expression is confined exclusively to the CFU-E erythroid precursor cells, but not in mature erythrocytes. These observations, together with previous data demonstrating a role for MLF1 in suppressing red cell maturation, suggest a possible role for MLF1IP and MLF1 deregulation in the genesis of erythroleukemias.

  20. Impact of non-thermal plasma surface modification on porous calcium hydroxyapatite ceramics for bone regeneration

    PubMed Central

    Moriguchi, Yu; Lee, Dae-Sung; Thamina, Khair; Masuda, Kazuto; Itsuki, Dai; Yoshikawa, Hideki; Hamaguchi, Satoshi; Myoui, Akira

    2018-01-01

    In the physiochemical sciences, plasma is used to describe an ionized gas. Previous studies have implicated plasma surface treatment in the enhancement of hydrophilicity of implanted musculoskeletal reconstructive materials. Hydroxyapatite (HA) ceramics, widely used in bone tissue regeneration, have made great advancements to skeletal surgery. In the present study, we investigate the impact of low-pressure plasma on the interconnected porous calcium hydroxyapatite (IP-CHA) both in vitro and in vivo. Our results indicate that dielectric barrier discharge (DBD) plasma, when used with oxygen, can augment the hydrophilicity of non-porous HA surfaces and the osteoconductivity of the IP-CHA disc via increased water penetration of inner porous structures, as demonstrated through microfocus computed tomography (μCT) assay. In vivo implantation of plasma-treated IP-CHA displayed superior bone ingrowth than untreated IP-CHA. Though plasma-treated IP-CHA did not alter osteoblast cell proliferation, it accelerated osteogenic differentiation of seeded marrow mesenchymal stem cells. In vitro X-ray photoelectron spectroscopy (XPS) revealed that this plasma treatment increases levels of oxygen, rather than nitrogen, on the plasma-treated IP-CHA surface. These findings suggest that plasma treatment, an easy and simple processing, can significantly improve the osteoconductive potential of commonly used artificial bones such as IP-CHA. Further optimization of plasma treatment and longer-term follow-up of in vivo application are required toward its clinical application. PMID:29538457

  1. Induced Pluripotent Stem (iPS) Cells in Dentistry: A Review

    PubMed Central

    Malhotra, Neeraj

    2016-01-01

    iPS cells are derived from somatic cells via transduction and expression of selective transcription factors. Both viral-integrating (like retroviral) and non-integrating (like, mRNA or protein-based) techniques are available for the production of iPS cells. In the field of dentistry, iPS cells have been derived from stem cells of apical papilla, dental pulp stem cells, and stem cells from exfoliated deciduous teeth, gingival and periodontal ligament fibroblasts, and buccal mucosa fibroblasts. iPS cells have the potential to differentiate into all derivatives of the 3 primary germ layers i.e. ectoderm, endoderm, and mesoderm. They are autogeneically accessible, and can produce patient-specific or disease-specific cell lines without the issue of ethical controversy. They have been successfully tested to produce mesenchymal stem cells-like cells, neural crest-like cells, ameloblasts-like cells, odontoblasts-like cells, and osteoprogenitor cells. These cells can aid in regeneration of periodontal ligament, alveolar bone, cementum, dentin-pulp complex, as well as possible Biotooth formation. However certain key issues like, epigenetic memory of iPS cells, viral-transduction, tumorgenesis and teratoma formation need to be overcome, before they can be successfully used in clinical practice. The article discusses the sources, pros and cons, and current applications of iPS cells in dentistry with an emphasis on encountered challenges and their solutions. PMID:27572712

  2. Plasma interferon-gamma-inducible protein-10 (IP-10) levels during acute hepatitis C virus infection

    PubMed Central

    Grebely, Jason; Feld, Jordan J.; Applegate, Tanya; Matthews, Gail V.; Hellard, Margaret; Sherker, Alana; Petoumenos, Kathy; Zang, Geng; Shaw, Ineke; Yeung, Barbara; George, Jacob; Teutsch, Suzy; Kaldor, John M.; Cherepanov, Vera; Bruneau, Julie; Shoukry, Naglaa H.; Lloyd, Andrew R.; Dore, Gregory J.

    2013-01-01

    Systemic levels of interferon-gamma-inducible protein-10 (IP-10) are predictive of treatment-induced clearance in chronic HCV. In the present study, factors associated with plasma IP-10 levels at the time of acute HCV detection and the association between IP-10 levels and spontaneous clearance were assessed in three cohorts of acute HCV infection. Among 300 individuals, 245 (181 male, 47 HIV+) were HCV RNA+ at acute HCV detection. In adjusted analysis, factors independently associated with IP-10 levels ≥150 pg/mL (median level) included HCV RNA levels >6 log IU/mL, HIV co-infection and non-Aboriginal ethnicity. Among 245 HCV RNA+ at acute HCV detection, 214 were untreated (n=137) or had persistent infection (infection duration ≥26 weeks) at treatment initiation (n=77). Spontaneous clearance occurred in 14% (29 of 214). Individuals without spontaneous clearance had significantly higher mean plasma IP-10 levels at the time of acute HCV detection than those with clearance (248±32 vs. 142±22 pg/mL, P=0.008). The proportion of individuals with spontaneous clearance was 0% (0 of 22, P=0.048) and 16% (27 of 165) and in those in those with and without plasma IP-10 levels ≥380 pg/mL. In adjusted analyses, favourable IL28B genotype was associated with spontaneous clearance, while higher HCV RNA level was independently associated with lower odds of spontaneous clearance. Conclusion High IP-10 levels at acute HCV detection were associated with failure to spontaneously clear HCV. Patients with acute HCV and high baseline IP-10 levels, particularly >380 pg/mL, should be considered for early therapeutic intervention, and those with low levels should defer therapy for potential spontaneous clearance. PMID:23325615

  3. Determination of the optimum number of cardiac cycles to differentiate intra-pulmonary shunt and patent foramen ovale by saline contrast two- and three-dimensional echocardiography.

    PubMed

    Bhatia, Nirmanmoh; Abushora, Mohannad Y; Donneyong, Macarius M; Stoddard, Marcus F

    2014-03-01

    Patent foramen ovale (PFO) and intra-pulmonary shunt (IPS) are potential causes of stroke. The most optimum cardiac cycle cutoff for bubbles to appear in the left heart on saline contrast transthoracic echocardiography (TTE) as criteria to differentiate the 2 entities is unknown. Ninety-five adult patients had saline contrast transesophageal echocardiography (TEE), two-dimensional (2D) and 3DTTE. Sensitivity and specificity of each cardiac cycle as cutoff to differentiate a PFO and IPS were obtained. Transesophageal echocardiography showed IPS in 28 and PFO in 15 patients. If bubbles appeared in the left heart within the first 4 cardiac cycles (the 4th cardiac cycle rule) as compared to alternate cutoffs, a PFO was most accurately diagnosed by both 2D and 3DTTE. Bubbles appearing at or after the 5th cardiac cycle most accurately determined an IPS. 3D versus 2DTTE had a trend for a higher sensitivity (61% vs. 36%, P = 0.06), but similar specificity (94% vs. 91%) for IPS. Accuracy of 3DTTE was 84% and 2DTTE was 75% (P = 0.08) for IPS. For PFO, 2DTTE sensitivity (87%) and specificity (98%) did not differ (P = NS) from that of 3DTTE sensitivity (73%) and specificity (100%). This study demonstrates for the first time that the 4th cardiac cycle rule differentiates PFO and IPS most optimally by 2D and 3DTTE. 3DTTE appears to have higher sensitivity for diagnosing IPS. These data suggest that 3DTTE is preferable when IPS is to be diagnosed. Both methods are similar for diagnosing PFO. © 2013, Wiley Periodicals, Inc.

  4. iTAR: a web server for identifying target genes of transcription factors using ChIP-seq or ChIP-chip data.

    PubMed

    Yang, Chia-Chun; Andrews, Erik H; Chen, Min-Hsuan; Wang, Wan-Yu; Chen, Jeremy J W; Gerstein, Mark; Liu, Chun-Chi; Cheng, Chao

    2016-08-12

    Chromatin immunoprecipitation followed by massively parallel DNA sequencing (ChIP-seq) or microarray hybridization (ChIP-chip) has been widely used to determine the genomic occupation of transcription factors (TFs). We have previously developed a probabilistic method, called TIP (Target Identification from Profiles), to identify TF target genes using ChIP-seq/ChIP-chip data. To achieve high specificity, TIP applies a conservative method to estimate significance of target genes, with the trade-off being a relatively low sensitivity of target gene identification compared to other methods. Additionally, TIP's output does not render binding-peak locations or intensity, information highly useful for visualization and general experimental biological use, while the variability of ChIP-seq/ChIP-chip file formats has made input into TIP more difficult than desired. To improve upon these facets, here we present are fined TIP with key extensions. First, it implements a Gaussian mixture model for p-value estimation, increasing target gene identification sensitivity and more accurately capturing the shape of TF binding profile distributions. Second, it enables the incorporation of TF binding-peak data by identifying their locations in significant target gene promoter regions and quantifies their strengths. Finally, for full ease of implementation we have incorporated it into a web server ( http://syslab3.nchu.edu.tw/iTAR/ ) that enables flexibility of input file format, can be used across multiple species and genome assembly versions, and is freely available for public use. The web server additionally performs GO enrichment analysis for the identified target genes to reveal the potential function of the corresponding TF. The iTAR web server provides a user-friendly interface and supports target gene identification in seven species, ranging from yeast to human. To facilitate investigating the quality of ChIP-seq/ChIP-chip data, the web server generates the chart of the characteristic binding profiles and the density plot of normalized regulatory scores. The iTAR web server is a useful tool in identifying TF target genes from ChIP-seq/ChIP-chip data and discovering biological insights.

  5. Integrated modeling of plasma ramp-up in DIII-D ITER-like and high bootstrap current scenario discharges

    NASA Astrophysics Data System (ADS)

    Wu, M. Q.; Pan, C. K.; Chan, V. S.; Li, G. Q.; Garofalo, A. M.; Jian, X.; Liu, L.; Ren, Q. L.; Chen, J. L.; Gao, X.; Gong, X. Z.; Ding, S. Y.; Qian, J. P.; Cfetr Physics Team

    2018-04-01

    Time-dependent integrated modeling of DIII-D ITER-like and high bootstrap current plasma ramp-up discharges has been performed with the equilibrium code EFIT, and the transport codes TGYRO and ONETWO. Electron and ion temperature profiles are simulated by TGYRO with the TGLF (SAT0 or VX model) turbulent and NEO neoclassical transport models. The VX model is a new empirical extension of the TGLF turbulent model [Jian et al., Nucl. Fusion 58, 016011 (2018)], which captures the physics of multi-scale interaction between low-k and high-k turbulence from nonlinear gyro-kinetic simulation. This model is demonstrated to accurately model low Ip discharges from the EAST tokamak. Time evolution of the plasma current density profile is simulated by ONETWO with the experimental current ramp-up rate. The general trend of the predicted evolution of the current density profile is consistent with that obtained from the equilibrium reconstruction with Motional Stark effect constraints. The predicted evolution of βN , li , and βP also agrees well with the experiments. For the ITER-like cases, the predicted electron and ion temperature profiles using TGLF_Sat0 agree closely with the experimental measured profiles, and are demonstrably better than other proposed transport models. For the high bootstrap current case, the predicted electron and ion temperature profiles perform better in the VX model. It is found that the SAT0 model works well at high IP (>0.76 MA) while the VX model covers a wider range of plasma current ( IP > 0.6 MA). The results reported in this paper suggest that the developed integrated modeling could be a candidate for ITER and CFETR ramp-up engineering design modeling.

  6. Novel model of negative secondary ion formation and its use to refine the electronegativity of almost fifty elements.

    PubMed

    Wittmaack, Klaus

    2014-06-17

    This study aimed to examine the recently proposed idea that the ionic contribution to atomic bonds is essential in determining the charge state of sputtered atoms. Use was made of negative secondary ion yields reported by Wilson for a large number of elements implanted in silicon and then sputter profiled by Cs bombardment. The derived normalized ion yields (or fractions) P vary by 6 orders of magnitude, but the expected exponential dependence on the electron affinity EA is evident only vaguely. Remarkably, a correlation of similar quality is observed if the data are presented as a function of the ionization potential IP. With IP being the dominant (if not sole) contributor to the electronegativity χ, one is led to assume that P depends on the sum χ + EA. About 72% of the "nonsaturated" ion yields are in accordance with a dependence of the form P ∝ exp[(χ + EA)/ε], with ε ≅ 0.2 eV, provided the appropriate value of χ is selected from the electronegativity tables of Pauling (read in eV), Mulliken or Allen. However, each of the three sources contributes only about one-third to the favorable electronegativity data. This unsatisfactory situation initiated the idea to derive the "true" electronegativity χSIMS from the measured ion yields P(χ + EA), verified for 48 elements. Significant negative deviations of χSIMS from a smooth increase with increasing atomic number are evident for elements with special outer-shell electron configurations such as (n-1)d(g-1)ns(1) or (n-1)d(10)ns(2)np(1). The results strongly support the new model of secondary ion formation and provide means for refining electronegativity data.

  7. The tuning of P-donor ligands: the aryl and other pendent group effects (PGEs) revisited.

    PubMed

    Poë, Anthony J

    2009-03-21

    Electronic and steric effects of P-donor ligands can be modified by varying the pendent groups attached to the phosphorus atoms. However, the so-called "Aryl Effects" of phosphites and other P-donor ligands that contain no aryl groups can be shown simply to be additional examples of electronic Pendent Group Effects (PGEs) by which effects are transmitted to the phosphorus atoms or through them. These effects are quite distinct from those caused by varying sigma-donicity and pi-acidity parameters, and are strictly proportional to the number of pendent groups of a particular type. In each case, the extent of the effect is determined by the difference between the actual property observed and that predicted on the basis that the ligand behaves in the same way as alkyl phosphines after allowing for steric and pi-acidity effects. The PGEs are therefore unique to particular pendent groups and to the method of measuring their effects. They are not "parameters" in the sense of being generally applicable in Linear Free Energy Relationships. The PGEs of a variety of pendent groups are derived from the so-called "aryl effects" determined by Giering & Prock et al. for vertical ionization potentials (IPs) and some other properties of the P-donor ligands. In almost all cases the IPs are reduced by the PGEs, and the extent of the reduction (in eV) decreases in the sequence C(6)F(5) (-0.67) approximately Cl (-0.67) < Pyrr (-0.53) < Ph (-0.49) < OR (-0.19) < OCH(2)CH(2)Cl (-0.07) < etpb (-0.03) < N(C(4)H(8)) (+0.01). Different PGEs are found for other P-donor-dependent properties although they are simply related to each other.

  8. Intranets: Just Another Bandwagon?

    ERIC Educational Resources Information Center

    Lynch, Gary

    1997-01-01

    Discusses intranets--the deployment and use of Internet technologies such as the World Wide Web, electronic mail, and Transmission Control Protocol/Internet Protocol (TCP/IP) on a closed network. Considers the "hype," benefits, standards, implementation, and problems of intranets, and concludes that while intranets can be beneficial,…

  9. Alpha2-adrenoceptor modulation of long-term potentiation elicited in vivo in rat occipital cortex.

    PubMed

    Mondaca, Mauricio; Hernández, Alejandro; Pérez, Hernán; Valladares, Luis; Sierralta, Walter; Fernández, Victor; Soto-Moyano, Rubén

    2004-09-24

    Pretreatment with the alpha(2)-adrenoceptor agonist clonidine (31.25, 62.5, or 125 microg/kg, i.p.) dose-dependently reduced long-term potentiation (LTP) elicited in vivo in the occipital cortex of anesthetized rats, whereas pretreatment with the alpha(2)-adrenoceptor antagonist yohimbine (0.133, 0.4, or 1.2 mg/kg, i.p.) increased neocortical LTP in a dose-dependent fashion. These effects could be related to the reported disruptive and facilitatory actions induced on memory formation by pretreatment with alpha(2)-adrenoceptor agonists and antagonists, respectively.

  10. News from the proton - recent DIS results from HERA

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

    Meier, K.

    1997-01-01

    Recent results from the two large general-purpose detectors H1 and ZEUS at HERA (DESY, Hamburg, Germany) are presented. Emphasis is given to the analysis of deep inelastic scattering defined by the observation of the scattered electron or positron in the main calorimeters. Results on purely inclusive cross sections lead to a determination of the charged (quarks) parton distribution F{sub 2}(x, Q{sup 2}). Access to the electrically neutral parton content (gluons) is obtained indirectly by an analysis of the expected scaling violation behavior of F{sub 2} or directly from multijet rates originating from well-defined initial parton configurations. Finally, the recently uncoveredmore » subclass of large rapidity gap (LRG) events has been analyzed in terms of F{sub 2}. The result supports the concept of a color neutral object (Pomeron IP) being probed by a hard scattering electron. Evidence for factorization of the Pomeron radiation process as well as for scaling in the inclusive IP structure functions has been found.« less

  11. Low- and room-temperature X-ray structures of protein kinase A ternary complexes shed new light on its activity.

    PubMed

    Kovalevsky, Andrey Y; Johnson, Hanna; Hanson, B Leif; Waltman, Mary Jo; Fisher, S Zoe; Taylor, Susan; Langan, Paul

    2012-07-01

    Post-translational protein phosphorylation by protein kinase A (PKA) is a ubiquitous signalling mechanism which regulates many cellular processes. A low-temperature X-ray structure of the ternary complex of the PKA catalytic subunit (PKAc) with ATP and a 20-residue peptidic inhibitor (IP20) at the physiological Mg(2+) concentration of ∼0.5 mM (LT PKA-MgATP-IP20) revealed a single metal ion in the active site. The lack of a second metal in LT PKA-MgATP-IP20 renders the β- and γ-phosphoryl groups of ATP very flexible, with high thermal B factors. Thus, the second metal is crucial for tight positioning of the terminal phosphoryl group for transfer to a substrate, as demonstrated by comparison of the former structure with that of the LT PKA-Mg(2)ATP-IP20 complex obtained at high Mg(2+) concentration. In addition to its kinase activity, PKAc is also able to slowly catalyze the hydrolysis of ATP using a water molecule as a substrate. It was found that ATP can be readily and completely hydrolyzed to ADP and a free phosphate ion in the crystals of the ternary complex PKA-Mg(2)ATP-IP20 by X-ray irradiation at room temperature. The cleavage of ATP may be aided by X-ray-generated free hydroxyl radicals, a very reactive chemical species, which move rapidly through the crystal at room temperature. The phosphate anion is clearly visible in the electron-density maps; it remains in the active site but slides about 2 Å from its position in ATP towards Ala21 of IP20, which mimics the phosphorylation site. The phosphate thus pushes the peptidic inhibitor away from the product ADP, while resulting in dramatic conformational changes of the terminal residues 24 and 25 of IP20. X-ray structures of PKAc in complex with the nonhydrolysable ATP analogue AMP-PNP at both room and low temperature demonstrated no temperature effects on the conformation and position of IP20.

  12. Influences of the Driver and Ambient Medium Characteristics on the Formation of Shocks in the Solar Atmosphere

    NASA Technical Reports Server (NTRS)

    Nat, Gopalswamy; Hong, Xie; Seiji, Yashiro; Pertti, Makela; Sachiko, Akiyama

    2010-01-01

    Traveling interplanetary (IP) shocks were discovered in the early 1960s, but their solar origin has been controversial. Early research focused on solar flares as the source of the shocks, but when coronal mass ejections (CMEs) were discovered, it became clear that fast CMEs clearly can drive the shocks. Type II radio bursts are excellent signatures of shocks near the Sun. The close correspondence between type II radio bursts and solar energetic particles (SEPs) makes it clear that the same shock accelerates ions and electrons. A recent investigation involving a large number of IP shocks revealed that about 35% of IP shocks do not produce type II bursts or SEPs. Comparing these radio quiet (RQ) shocks with the radio loud (RL) ones revealed some interesting results: (1) there is no evidence for blast waves, in that all IP shocks can be attributed to CMEs, (2) a small fraction (20%) of RQ shocks is associated with ion enhancements at the shocks when they move past the observing spacecraft, (3) the primary difference between the RQ and RL shocks can be traced to the different kinematic properties of the associated CMEs and the variation of the characteristic speeds of the ambient medium, and (4) the shock properties measured at 1 AU are not too different for the RQ and RL cases due to the interaction of the shock driver with the IP medium that seems to erase the difference.

  13. Red Wine Consumption is inversely associated with 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-DNA Adduct Levels in Prostate

    PubMed Central

    Rybicki, Benjamin A.; Neslund-Dudas, Christine; Bock, Cathryn H.; Nock, Nora L.; Rundle, Andrew; Jankowski, Michelle; Levin, Albert M.; Beebe-Dimmer, Jennifer; Savera, Adnan T.; Takahashi, Satoru; Shirai, Tomoyuki; Tang, Deliang

    2011-01-01

    In humans, genetic variation and dietary factors may alter the biologic effects of exposure to 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), one of the major heterocyclic amines generated from cooking meats at high temperatures that has carcinogenic potential through the formation of DNA adducts. Previously, we reported grilled red meat consumption associated with PhIP-DNA adduct levels in human prostate. In the present study, we expanded our investigation to estimate the associations between beverage consumption and PhIP-DNA adduct levels in prostate for 391 prostate cancer cases. Of the 15 beverages analyzed, red wine consumption had the strongest association with PhIP-DNA adduct levels showing an inverse correlation in both tumor (p=0.006) and non-tumor (p=0.002) prostate cells. Red wine consumption differed significantly between African-American and white cases, but PhIP-DNA adduct levels in prostate did not vary by race. In African Americans compared with whites, however, associations between red wine consumption and PhIP-DNA adduct levels were not as strong as associations with specific (e.g., SULT1A1 and UGT1A10 genotypes) and non-specific (e.g., African ancestry) genetic variation. In a multivariable model, the covariate for red wine consumption explained a comparable percentage (13-16%) of the variation in PhIP-DNA adduct levels in prostate across the two racial groups, but the aforementioned genetic factors explained 33% of the PhIP-DNA adduct variation in African-American cases, while only 19% of the PhIPDNA adduct variation in whites. We conclude that red wine consumption may counteract biologic effects of PhIP exposure in human prostate, but genetic factors may play an even larger role, particularly in African Americans. PMID:21846795

  14. ANTIPROLIFERATIVE EFFECT OF INOSITOL HEXAPHOSPHATE ON HUMAN SKIN MELANOMA CELLS IN VITRO.

    PubMed

    Wawszczyk, Joanna; Kapral, Małgorzata; Lodowska, Jolanta; Jesse, Katarzyna; Hollek, Andrzej; Węglarz, Ludmiła

    2015-01-01

    Human malignant melanoma is a highly metastatic tumor with poor prognosis. The majority of metastatic melanomas are resistant to diverse chemotherapeutic agents. Consequently, the search for novel antimelanoma agents continues. In recent years, the interest in plants and their biologically active constituents as a source of novel potential drugs significantly increased. Inositol hexaphosphate (IP6) is a naturally occurring compound that has been shown to inhibit the growth of a wide variety of tumor cells in multiple experimental model systems. The aim of this study was to evaluate the antiproliferative and cytotoxic influence of IP6 on melanotic melanoma cells in vitro. The A2058 cells used as a model of human skin melanoma malignum were exposed to different concentrations of IP6 (0.1-5 mM) for a various period of time and their growth was determined by sulforhodamine B assay after 24, 48 and 72 h. The cytotoxicity of IP6 was measured at 24 and 72 h by XTT assay. IP6 has been found to cause dose-dependent growth suppression of A2058 melanoma cells. At low concentrations (0.1 and 0.5 mM) it did not exert any influence on the cell proliferation as compared to control cultures. Higher concentrations of IP6 (from 1 to 5 mM) had a statistically significant, suppressive effect on cell proliferation after 24 h incubation. When the experimental time period was increased up to 72 h, statistically significant inhibition of cell proliferation was monitored at all IP6 concentrations used. Data obtained from XTT assay indicated that IP6 had dose- and time-dependent cytotoxic effect on melanoma cells. The results demonstrate the antiproliferative and cytotoxic properties of IP6 in a wide range of concentrations on human A2058 melanoma cells. Hence, it can be suggested that IP6 could have a promising therapeutic significance in treating cancer.

  15. Anomalous diffusion of Ibuprofen in cyclodextrin nanosponge hydrogels: an HRMAS NMR study.

    PubMed

    Ferro, Monica; Castiglione, Franca; Punta, Carlo; Melone, Lucio; Panzeri, Walter; Rossi, Barbara; Trotta, Francesco; Mele, Andrea

    2014-01-01

    Ibuprofen sodium salt (IP) was encapsulated in cyclodextrin nanosponges (CDNS) obtained by cross-linking of β-cyclodextrin with ethylenediaminetetraacetic acid dianhydride (EDTAn) in two different preparations: CDNSEDTA 1:4 and 1:8, where the 1:n notation indicates the CD to EDTAn molar ratio. The entrapment of IP was achieved by swelling the two polymers with a 0.27 M solution of IP in D2O, leading to colourless, homogeneous hydrogels loaded with IP. The molecular environment and the transport properties of IP in the hydrogels were studied by high resolution magic angle spinning (HRMAS) NMR spectroscopy. The mean square displacement (MSD) of IP in the gels was obtained by a pulsed field gradient spin echo (PGSE) NMR pulse sequence at different observation times t d. The MSD is proportional to the observation time elevated to a scaling factor α. The α values define the normal Gaussian random motion (α = 1), or the anomalous diffusion (α < 1, subdiffusion, α > 1 superdiffusion). The experimental data here reported point out that IP undergoes subdiffusive regime in CDNSEDTA 1:4, while a slightly superdiffusive behaviour is observed in CDNSEDTA 1:8. The transition between the two dynamic regimes is triggered by the polymer structure. CDNSEDTA 1:4 is characterized by a nanoporous structure able to induce confinement effects on IP, thus causing subdiffusive random motion. CDNSEDTA 1:8 is characterized not only by nanopores, but also by dangling EDTA groups ending with ionized COO(-) groups. The negative potential provided by such groups to the polymer backbone is responsible for the acceleration effects on the IP anion thus leading to the superdiffusive behaviour observed. These results point out that HRMAS NMR spectroscopy is a powerful direct method for the assessment of the transport properties of a drug encapsulated in polymeric scaffolds. The diffusion properties of IP in CDNS can be modulated by suitable polymer synthesis; this finding opens the possibility to design suitable systems for drug delivery with predictable and desired drug release properties.

  16. Circularly polarized harmonic generation by intense bicircular laser pulses: electron recollision dynamics and frequency dependent helicity

    NASA Astrophysics Data System (ADS)

    Bandrauk, André D.; Mauger, François; Yuan, Kai-Jun

    2016-12-01

    Numerical solutions of time-dependent Schrödinger equations for one and two electron cyclic molecules {{{H}}}nq+ exposed to intense bichromatic circularly polarized laser pulses of frequencies {ω }1 and {ω }2, such that {ω }1/{ω }2={n}1/{n}2 (integer) produce circularly polarized high order harmonics with a cut-off recollision maximum energy at and greater than the linear polarization law (in atomic units) {N}m{ω }1={I}p+3.17{U}p, where I p is the ionization potential and {U}p={(2{E}0)}2/4{ω }2 is the ponderomotive energy defined by the field E 0 (intensity I={{cE}}02/8π ) from each pulse and mean frequency ω =({ω }1+{ω }2)/2 . An electron recollision model in a rotating frame at rotating frequency {{Δ }}ω =({ω }1-{ω }2)/2 predicts this simple result as a result of recollision dynamics in a combination of bichromatic circularly polarized pulses. The harmonic helicities and their intensities are shown to depend on compatible symmetries of the net pulse electric fields with that of the molecules.

  17. Oligo p-Phenylenevinylene Derivatives as Electron Transfer Matrices for UV-MALDI

    NASA Astrophysics Data System (ADS)

    Castellanos-García, Laura J.; Agudelo, Brian Castro; Rosales, Hernando F.; Cely, Melissa; Ochoa-Puentes, Christian; Blanco-Tirado, Cristian; Sierra, Cesar A.; Combariza, Marianny Y.

    2017-12-01

    Phenylenevinylene oligomers (PVs) have outstanding photophysical characteristics for applications in the growing field of organic electronics. Yet, PVs are also versatile molecules, the optical and physicochemical properties of which can be tuned by manipulation of their structure. We report the synthesis, photophysical, and MS characterization of eight PV derivatives with potential value as electron transfer (ET) matrices for UV-MALDI. UV-vis analysis show the presence of strong characteristic absorption bands in the UV region and molar absorptivities at 355 nm similar or higher than those of traditional proton (CHCA) and ET (DCTB) MALDI matrices. Most of the PVs exhibit non-radiative quantum yields (φ) above 0.5, indicating favorable thermal decay. Ionization potential values (IP) for PVs, calculated by the Electron Propagator Theory (EPT), range from 6.88 to 7.96 eV, making these oligomers good candidates as matrices for ET ionization. LDI analysis of PVs shows only the presence of radical cations (M+.) in positive ion mode and absence of clusters, adducts, or protonated species; in addition, M+. threshold energies for PVs are lower than for DCTB. We also tested the performance of four selected PVs as ET MALDI matrices for analytes ranging from porphyrins and phthalocyanines to polyaromatic compounds. Two of the four PVs show S/N enhancement of 1961% to 304% in comparison to LDI, and laser energy thresholds from 0.17 μJ to 0.47 μJ compared to 0.58 μJ for DCTB. The use of PV matrices also results in lower LODs (low fmol range) whereas LDI LODs range from pmol to nmol. [Figure not available: see fulltext.

  18. Antidiarrhoeal activity of seed extract of Albizzia lebbeck Benth.

    PubMed

    Besra, S E; Gomes, A; Chaudhury, L; Vedasiromoni, J R; Ganguly, D K

    2002-09-01

    The antidiarrhoeal activity of the seed extract of Albizzia lebbeck (Benth.) was investigated employing conventional rodent models of diarrhoea, i.e. castor oil-induced diarrhoea, upper gastrointestinal transit (u.g.t.) and fluid secretion. It was found that the aqueous methanol extract of Albizzia lebbeck seeds (2.5-5 mg/kg i.p.) possessed antidiarrhoeal activity which strengthens the earlier use of the seeds in the treatment of diarrhoea and dysentery. The antidiarrhoeal dose of the extract was at least 10-30 times less than the LD(50) dose. The extract (2.5-5 mg/kg i.p.) potentiated the antidiarrhoeal activity of loperamide (1 mg/kg i.p.). Nalaxone (0.5 mg/kg i.p.) significantly inhibited the antidiarrhoeal activity of the extract as well as loperamide, thus indicating a role of the opioid system in the antidiarrhoeal activity of the extract. Copyright 2002 John Wiley & Sons, Ltd.

  19. Recent advances in ChIP-seq analysis: from quality management to whole-genome annotation.

    PubMed

    Nakato, Ryuichiro; Shirahige, Katsuhiko

    2017-03-01

    Chromatin immunoprecipitation followed by sequencing (ChIP-seq) analysis can detect protein/DNA-binding and histone-modification sites across an entire genome. Recent advances in sequencing technologies and analyses enable us to compare hundreds of samples simultaneously; such large-scale analysis has potential to reveal the high-dimensional interrelationship level for regulatory elements and annotate novel functional genomic regions de novo. Because many experimental considerations are relevant to the choice of a method in a ChIP-seq analysis, the overall design and quality management of the experiment are of critical importance. This review offers guiding principles of computation and sample preparation for ChIP-seq analyses, highlighting the validity and limitations of the state-of-the-art procedures at each step. We also discuss the latest challenges of single-cell analysis that will encourage a new era in this field. © The Author 2016. Published by Oxford University Press.

  20. The interaction between intellectual property and drug regulatory systems: global perspectives.

    PubMed

    Madden, Edward A

    2007-02-01

    Regulatory compliance in the development, production and sale of new drugs accounts for the largest single expense in bringing a drug product to market. To justify developmental and regulatory compliance costs, drug innovators turn to the intellectual property (IP) system to provide a means for securing returns on investment. Because the drug regulatory system in most countries operates in isolation of the IP system, one of the greatest challenges facing the pharmaceutical industry is the extent to which IP rights can be managed against an independent drug regulatory system. Many regulatory bodies in developed countries have sought to ensure a compromise between the rights of generic companies and IP owners by including safeguards in the regulatory framework, such as patent linking and data protection; however, these efforts are yet to be applied in some of the biggest potential drug markets in emerging economies.

  1. Generation of an ICF syndrome model by efficient genome editing of human induced pluripotent stem cells using the CRISPR system.

    PubMed

    Horii, Takuro; Tamura, Daiki; Morita, Sumiyo; Kimura, Mika; Hatada, Izuho

    2013-09-30

    Genome manipulation of human induced pluripotent stem (iPS) cells is essential to achieve their full potential as tools for regenerative medicine. To date, however, gene targeting in human pluripotent stem cells (hPSCs) has proven to be extremely difficult. Recently, an efficient genome manipulation technology using the RNA-guided DNase Cas9, the clustered regularly interspaced short palindromic repeats (CRISPR) system, has been developed. Here we report the efficient generation of an iPS cell model for immunodeficiency, centromeric region instability, facial anomalies syndrome (ICF) syndrome using the CRISPR system. We obtained iPS cells with mutations in both alleles of DNA methyltransferase 3B (DNMT3B) in 63% of transfected clones. Our data suggest that the CRISPR system is highly efficient and useful for genome engineering of human iPS cells.

  2. Survival of resin infiltrated ceramics under influence of fatigue.

    PubMed

    Aboushelib, Moustafa N; Elsafi, Mohamed H

    2016-04-01

    to evaluate influence of cyclic fatigue on two resin infiltrated ceramics and three all-ceramic crowns manufactured using CAD/CAM technology. CAD/CAM anatomically shaped crowns were manufactured using two resin infiltrated ceramics (Lava Ultimate and Vita Enamic), two reinforced glass ceramic milling blocks ((IPS)Empress CAD and (IPS)e.max CAD) and a veneered zirconia core ((IPS)Zir CAD). (IPS)e.max CAD and (IPS)Zir CAD were milled into 0.5mm thick anatomically shaped core structure which received standardized press-on veneer ceramic. The manufactured crowns were cemented on standardized resin dies using a resin adhesive (Panavia F2.0). Initial fracture strength of half of the specimens was calculated using one cycle load to failure in a universal testing machine. The remaining crowns were subjected to 3.7 million chewing cycles (load range 50-200N at 3s interval) in a custom made pneumatic fatigue tester. Survival statistics were calculated and Weibull modulus was measured from fitted load-cycle-failure diagrams. Scanning electron microscopy was performed to fractographically analyze fractured surfaces. Data were analyzed using two way analysis of variance and Bonferroni post hoc tests (α=0.05). Dynamic fatigue resulted in significant reduction (F=7.54, P<0.005) of the initial fracture strength of the tested specimens. Zirconia showed the highest deterioration percent (34% reduction in strength) followed by (IPS)Empress (32.2%), (IPS)e.max (27.1%) while Lava Ultimate and Vita Enamic showed the lowest percent of reduction in strength. The two types of resin infiltrated ceramics and (IPS)Empress demonstrated the highest percent of fracture incidences under the influence of fatigue (35-45% splitting). None of the tested veneered zirconia restorations were fractured during testing, however, chipping of the veneer ceramics was observed in 6 crowns. The lowest percent of failure was observed for (IPS)e.max crowns manifested as 3 cases of minor chipping in addition to two complete fracture incidences. SEM images demonstrated the internal structure of the tested materials and detected location and size of the critical crack. The internal structure of the tested materials significantly influenced their fatigue behavior. Resin infiltrated ceramics were least influenced by fatigue while the characteristic strength of zirconia prevented core fracture but failure still occurred from the weaker veneer ceramic. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  3. Safety incentive and penalty provisions in Indian construction projects and their impact on safety performance.

    PubMed

    Hasan, Abid; Jha, Kumar Neeraj

    2013-01-01

    Safety incentive and penalty (I/P) provisions in construction contracts are one of the most common forms of I/P. Contradictory opinions on the effectiveness of these provisions have been expressed in the literature. Statistics on safety provisions were collected from 32 construction projects, which include both types of contracts - those with safety I/P provisions and those without them. Although inclusion of safety I/P provisions in contracts helps in improving the overall safety performance in construction projects, further scope for improvement still exists. Literature review and structured personal interviews, coupled with a survey based on preliminary questionnaire, revealed that successful formulation and implementation of such provisions are dependent on 25 attributes which need the attention of both clients and contractors. A questionnaire-based survey was conducted to evaluate these attributes. The six factors extracted by carrying out factor analysis are: incentive distribution method, proper labour training, special attention to risky situations, role of safety committee and sub-contractors, specialised works and safety equipments, and right form of I/P. If taken care of, these attributes have the potential to improve the safety performance in construction projects. The results would be useful to clients and contractors in implementing the safety I/P provisions and thereby improving safety performance.

  4. Liposome-encapsulated diacyl glycerol and inositol triphosphate-induced delayed oocyte activation and poor development of parthenotes.

    PubMed

    Nair, Ramya; Manikkath, Jyothsna; Hegde, Aswathi R; Mutalik, Srinivas; Kalthur, Guruprasad; Adiga, Satish Kumar

    2017-09-01

    To explore the ability of diacyl glycerol (DAG) and inositol triphosphate (IP3), two major secondary messengers in the calcium signaling pathway, in activating oocytes. Oocyte cumulus complex obtained from superovulated Swiss albino mice were incubated in M16 medium with liposome-encapsulated 1,2-Dipalmitoyl-sn-glycerol (LEDAG) and/or IP3 for 3 h. Strontium chloride was used as positive control. The activation potential, ploidy status, and blastocyst rate was calculated. Both DAG and IP3, individually, induced activation in ~98% of oocytes, which was significantly higher (p<0.01) than activation induced by strontium chloride (60%). Delayed pronucleus formation and a higher percentage of diploid parthenotes was observed in oocytes activated with LEDAG and/or IP3. However, these embryos failed to progress beyond the 6-8-cell stage. Only when the medium was supplemented with LEDAG (5 μg/mL) and IP3 (10 μg/mL) could activated oocytes progress till the blastocyst stage (5.26%), which was lower than the blastocyst rate in the positive controls (13.91%). The results of the present study indicate that DAG and IP3 can induce delayed oocyte activation and poor development of parthenotes in vitro.

  5. Differentiation of Odontoblast-Like Cells From Mouse Induced Pluripotent Stem Cells by Pax9 and Bmp4 Transfection.

    PubMed

    Seki, Daisuke; Takeshita, Nobuo; Oyanagi, Toshihito; Sasaki, Shutaro; Takano, Ikuko; Hasegawa, Masakazu; Takano-Yamamoto, Teruko

    2015-09-01

    The field of tooth regeneration has progressed in recent years, and human tooth regeneration could become viable in the future. Because induced pluripotent stem (iPS) cells can differentiate into odontogenic cells given appropriate conditions, iPS cells are a potential cell source for tooth regeneration. However, a definitive method to induce iPS cell-derived odontogenic cells has not been established. We describe a novel method of odontoblast differentiation from iPS cells using gene transfection. We generated mouse iPS cell-derived neural crest-like cells (iNCLCs), which exhibited neural crest markers. Next, we differentiated iNCLCs into odontoblast-like cells by transfection of Pax9 and Bmp4 expression plasmids. Exogenous Pax9 upregulated expression of Msx1 and dentin matrix protein 1 (Dmp1) in iNCLCs but not bone morphogenetic protein 4 (Bmp4) or dentin sialophosphoprotein (Dspp). Exogenous Bmp4 upregulated expression of Msx1, Dmp1, and Dspp in iNCLCs, but not Pax9. Moreover, cotransfection of Pax9 and Bmp4 plasmids in iNCLCs revealed a higher expression of Pax9 than when Pax9 plasmid was used alone. In contrast, exogenous Pax9 downregulated Bmp4 overexpression. Cotransfection of Pax9 and Bmp4 synergistically upregulated Dmp1 expression; however, Pax9 overexpression downregulated exogenous Bmp4-induced Dspp expression. Together, these findings suggest that an interaction between exogenous Pax9- and Bmp4-induced signaling modulated Dmp1 and Dspp expression. In conclusion, transfection of Pax9 and Bmp4 expression plasmids in iNCLCs induced gene expression associated with odontoblast differentiation, suggesting that iNCLCs differentiated into odontoblast-like cells. The iPS cell-derived odontoblast-like cells could be a useful cell source for tooth regeneration. It has been reported that induced pluripotent stem (iPS) cells differentiate into odontogenic cells by administration of recombinant growth factors and coculture with odontogenic cells. Therefore, they can be potential cell sources for tooth regeneration. However, these previous methods still have problems, such as usage of other cell types, heterogeneity of differentiated cells, and tumorigenicity. In the present study, a novel method to differentiate iPS cells into odontoblast-like cells without tumorigenicity using gene transfection was established. It is an important advance in the establishment of efficient methods to generate homogeneous functional odontogenic cells derived from iPS cells. ©AlphaMed Press.

  6. Ethanol potentiates the genotoxicity of the food-derived mammary carcinogen PhIP in human estrogen receptor-positive mammary cells: mechanistic support for lifestyle factors (cooked red meat and ethanol) associated with mammary cancer.

    PubMed

    Malik, Durr-E-Shahwar; David, Rhiannon M; Gooderham, Nigel J

    2018-04-01

    Consumption of cooked/processed meat and ethanol are lifestyle risk factors in the aetiology of breast cancer. Cooking meat generates heterocyclic amines such as 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Epidemiology, mechanistic and animal studies indicate that PhIP is a mammary carcinogen that could be causally linked to breast cancer incidence; PhIP is DNA damaging, mutagenic and oestrogenic. PhIP toxicity involves cytochrome P450 (CYP1 family)-mediated metabolic activation to DNA-damaging species, and transcriptional responses through Aryl hydrocarbon receptor (AhR) and estrogen-receptor-α (ER-α). Ethanol consumption is a modifiable lifestyle factor strongly associated with breast cancer risk. Ethanol toxicity involves alcohol dehydrogenase metabolism to reactive acetaldehyde, and is also a substrate for CYP2E1, which when uncoupled generates reactive oxygen species (ROS) and DNA damage. Here, using human mammary cells that differ in estrogen-receptor status, we explore genotoxicity of PhIP and ethanol and mechanisms behind this toxicity. Treatment with PhIP (10 -7 -10 -4 M) significantly induced genotoxicity (micronuclei formation) preferentially in ER-α positive human mammary cell lines (MCF-7, ER-α+) compared to MDA-MB-231 (ER-α-) cells. PhIP-induced CYP1A2 in both cell lines but CYP1B1 was selectively induced in ER-α(+) cells. ER-α inhibition in MCF-7 cells attenuated PhIP-mediated micronuclei formation and CYP1B1 induction. PhIP-induced CYP2E1 and ROS via ER-α-STAT-3 pathway, but only in ER-α (+) MCF-7 cells. Importantly, simultaneous treatments of physiological concentrations ethanol (10 -3 -10 -1 M) with PhIP (10 -7 -10 -4 M) increased oxidative stress and genotoxicity in MCF-7 cells, compared to the individual chemicals. Collectively, these data offer a mechanistic basis for the increased risk of breast cancer associated with dietary cooked meat and ethanol lifestyle choices.

  7. The Effects of Pushing the Digital Divide to the Fighting Hole

    DTIC Science & Technology

    2006-02-03

    information technologies (IT), and new ways of horizontally fusing information across the battlespace...The opportunity to exploit this new “digital...brought technology , such as the Internet Protocol (IP), to the forefront. It is incumbent upon the leaders of the communications community to ensure...in a recent interview with SIGNAL magazine: In terms of potential, I see the fundamental technologies associated with Internet Protocol (IP

  8. Involvement of IP3 Receptors in LTP and LTD Induction in Guinea Pig Hippocampal CA1 Neurons

    ERIC Educational Resources Information Center

    Taufiq, Ahmed Mostafa; Fujii, Satoshi; Yamazaki, Yoshihiko; Sasaki, Hiroshi; Kaneko, Kenya; Li, Jianmin; Kato, Hiroshi; Mikoshiba, Katsuhiko

    2005-01-01

    The role of inositol 1, 4, 5-trisphosphate receptors (IP3Rs) in long-term potentiation (LTP) and long-term depression (LTD) was studied in CA1 neurons in guinea pig hippocampal slices. In standard solution, short tetanic stimulation consisting of 15 pulses at 100 Hz induced LTP, while three short trains of low-frequency stimulation (LFS; 200…

  9. Multi-service terminal adapter based on IP technology applications in rural area

    NASA Astrophysics Data System (ADS)

    Gao, Li; Li, Xiaobo; Yan, Juntao; Ren, Xupeng

    Take advantage of ample modern existing telecom network resources to rural areas may achieve it's information society gradually. This includes the establishment of integrated rural information service platform, modern remote education center and electronic administration management platform for rural areas. The geographical and economic constraints must be overcome for structuring the rural service support system, in order to provide technical support, information products and information services to modern rural information service system. It is important that development an access platform based IP technology, which supports multi-service access in order to implement a variety of types of mobile terminal equipment adapter access and to reduce restrictions on mobile terminal equipment.

  10. The metastasis suppressor RARRES3 as an endogenous inhibitor of the immunoproteasome expression in breast cancer cells

    NASA Astrophysics Data System (ADS)

    Anderson, Alison M.; Kalimutho, Murugan; Harten, Sarah; Nanayakkara, Devathri M.; Khanna, Kum Kum; Ragan, Mark A.

    2017-01-01

    In breast cancer metastasis, the dynamic continuum involving pro- and anti-inflammatory regulators can become compromised. Over 600 genes have been implicated in metastasis to bone, lung or brain but how these genes might contribute to perturbation of immune function is poorly understood. To gain insight, we adopted a gene co-expression network approach that draws on the functional parallels between naturally occurring bone marrow-derived mesenchymal stem cells (BM-MSCs) and cancer stem cells (CSCs). Our network analyses indicate a key role for metastasis suppressor RARRES3, including potential to regulate the immunoproteasome (IP), a specialized proteasome induced under inflammatory conditions. Knockdown of RARRES3 in near-normal mammary epithelial and breast cancer cell lines increases overall transcript and protein levels of the IP subunits, but not of their constitutively expressed counterparts. RARRES3 mRNA expression is controlled by interferon regulatory factor IRF1, an inducer of the IP, and is sensitive to depletion of the retinoid-related receptor RORA that regulates various physiological processes including immunity through modulation of gene expression. Collectively, these findings identify a novel regulatory role for RARRES3 as an endogenous inhibitor of IP expression, and contribute to our evolving understanding of potential pathways underlying breast cancer driven immune modulation.

  11. Using Human Induced Pluripotent Stem Cells to Model Skeletal Diseases.

    PubMed

    Barruet, Emilie; Hsiao, Edward C

    2016-01-01

    Musculoskeletal disorders affecting the bones and joints are major health problems among children and adults. Major challenges such as the genetic origins or poor diagnostics of severe skeletal disease hinder our understanding of human skeletal diseases. The recent advent of human induced pluripotent stem cells (human iPS cells) provides an unparalleled opportunity to create human-specific models of human skeletal diseases. iPS cells have the ability to self-renew, allowing us to obtain large amounts of starting material, and have the potential to differentiate into any cell types in the body. In addition, they can carry one or more mutations responsible for the disease of interest or be genetically corrected to create isogenic controls. Our work has focused on modeling rare musculoskeletal disorders including fibrodysplasia ossificans progressive (FOP), a congenital disease of increased heterotopic ossification. In this review, we will discuss our experiences and protocols differentiating human iPS cells toward the osteogenic lineage and their application to model skeletal diseases. A number of critical challenges and exciting new approaches are also discussed, which will allow the skeletal biology field to harness the potential of human iPS cells as a critical model system for understanding diseases of abnormal skeletal formation and bone regeneration.

  12. TRAF3IP2 Mediates Aldosterone/Salt-Induced Cardiac Hypertrophy and Fibrosis

    PubMed Central

    Sakamuri, Siva S.V.P; Valente, Anthony J.; Siddesha, Jalahalli M.; Delafontaine, Patrice; Siebenlist, Ulrich; Gardner, Jason D.; Chandrasekar, Bysani

    2016-01-01

    Aberrant activation of the renin-angiotensin-aldosterone system (RAAS) contributes to adverse cardiac remodeling and eventual failure. Here we investigated whether TRAF3-interacting Protein 2 (TRAF3IP2), a redox-sensitive cytoplasmic adaptor molecule and an upstream regulator of nuclear factor-κB (NF-κB) and activator protein-1 (AP-1), mediates aldosterone-induced cardiac hypertrophy and fibrosis. Wild type (WT) and TRAF3IP2-null mice were infused with aldosterone (0.2mg/kg/day) for 4 weeks along with 1%NaCl in drinking water. Aldosterone/salt, but not salt alone, upregulated TRAF3IP2 expression in WT mouse hearts. Aldosterone elevated blood pressure to a similar extent in both WT and TRAF3IP2-null groups. Importantly, TRAF3IP2 gene deletion attenuated aldosterone/salt-induced (i) p65 and c-Jun activation, (ii) extracellular matrix (collagen Iα1 and collagen 3α1), matrix metalloproteinase (MMP2), lysyl oxidase (LOX), inflammatory cytokine (IL-6 and IL-18), chemokine (CXCL1 and CXCL2), and adhesion molecule (ICAM1) gene expression in hearts, (iii) IL-6, IL-18, and MMP2 protein levels, (iv) systemic IL-6 and IL-18 levels, and (iv) cardiac hypertrophy and fibrosis. These results indicate that TRAF3IP2 is a critical signaling intermediate in aldosterone/salt-induced myocardial hypertrophy and fibrosis, and thus a potential therapeutic target in hypertensive heart disease. PMID:27040306

  13. TRAF3IP2 mediates aldosterone/salt-induced cardiac hypertrophy and fibrosis.

    PubMed

    Sakamuri, Siva S V P; Valente, Anthony J; Siddesha, Jalahalli M; Delafontaine, Patrice; Siebenlist, Ulrich; Gardner, Jason D; Bysani, Chandrasekar

    2016-07-05

    Aberrant activation of the renin-angiotensin-aldosterone system (RAAS) contributes to adverse cardiac remodeling and eventual failure. Here we investigated whether TRAF3 Interacting Protein 2 (TRAF3IP2), a redox-sensitive cytoplasmic adaptor molecule and an upstream regulator of nuclear factor-κB (NF-κB) and activator protein-1 (AP-1), mediates aldosterone-induced cardiac hypertrophy and fibrosis. Wild type (WT) and TRAF3IP2-null mice were infused with aldosterone (0.2 mg/kg/day) for 4 weeks along with 1%NaCl in drinking water. Aldosterone/salt, but not salt alone, upregulated TRAF3IP2 expression in WT mouse hearts. Further, aldosterone elevated blood pressure to a similar extent in both WT and TRAF3IP2-null groups. However, TRAF3IP2 gene deletion attenuated aldosterone/salt-induced (i) p65 and c-Jun activation, (ii) extracellular matrix (collagen Iα1 and collagen IIIα1), matrix metalloproteinase (MMP2), lysyl oxidase (LOX), inflammatory cytokine (IL-6 and IL-18), chemokine (CXCL1 and CXCL2), and adhesion molecule (ICAM1) mRNA expression in hearts, (iii) IL-6, IL-18, and MMP2 protein levels, (iv) systemic IL-6 and IL-18 levels, and (iv) cardiac hypertrophy and fibrosis. These results indicate that TRAF3IP2 is a critical signaling intermediate in aldosterone/salt-induced myocardial hypertrophy and fibrosis, and thus a potential therapeutic target in hypertensive heart disease. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  14. The effect of esophagogastroduodenoscopy probe insertion on the intracuff pressure of airway devices in children during general anesthesia.

    PubMed

    Balaban, Onur; Kamata, Mineto; Hakim, Mumin; Tumin, Dmitry; Tobias, Joseph D

    2017-04-01

    Given the size of the esophagogastroduodenoscopy (EGD) probe and the compressibility of the pediatric airway, the EGD probe may increase the intracuff pressure (IP) of an airway device. The current study evaluated IP changes during EGD examination under general anesthesia in pediatric patients. Following the induction of anesthesia, a laryngeal mask airway (LMA) or endotracheal tube (ETT) was placed without neuromuscular blockade. The IP was measured at baseline, during EGD probe insertion, while the EGD probe was in place, and after probe removal. The study cohort included 101 patients (mean age 11.3 years). The airway was secured with an LMA and an ETT in 88 and 13 patients, respectively. The IP increased from 27 ± 15 cmH 2 O at baseline to 34 ± 17 cmH 2 O during probe insertion (p < 0.001), remained at 33 ± 16 cmH 2 O while the probe was in place, and decreased to 26 ± 14 cmH 2 O after probe removal. The IP of the LMA or ETT increased during EGD probe insertion and remained elevated while the probe was in place. High IP may compromise mucosal perfusion resulting in a sore throat when using an LMA or the potential for airway damage if an ETT is used. Removal of air from the cuff and titration of the IP should be considered after EGD insertion.

  15. Electron-beam-induced topographical, chemical, and structural patterning of amorphous titanium oxide films.

    PubMed

    Kern, P; Müller, Y; Patscheider, J; Michler, J

    2006-11-30

    Electrolytically deposited amorphous TiO2 films on steel are remarkably sensitive to electron beam (e-beam) irradiation at moderate energies at 20 keV, resulting in controlled local oxide reduction and crystallization, opening the possibility for local topographical, chemical, and structural modifications within a biocompatible, amorphous, and semiconducting matrix. The sensitivity is shown to vary significantly with the annealing temperature of as-deposited films. Well-defined irradiation conditions in terms of probe current IP (5 microA) and beam size were achieved with an electron probe microanalyzer. As shown by atomic force and optical microscopy, micro-Raman spectroscopy, wavelength-dispersive X-ray (WDX), and Auger analyses, e-beam exposure below 1 Acm-2 immediately leads to electron-stimulated oxygen desorption, resulting in a well-defined volume loss primarily limited to the irradiated zone under the electron probe and in a blue color shift in this zone because of the presence of Ti2O3. Irradiation at 5 Acm(-2) (IP = 5 microA) results in local crystallization into anatase phase within 1 s of exposure and in reduction to TiO after an extended exposure of 60 s. Further reduction to the metallic state could be observed after 60 s of exposure at approximately 160 Acm(-2). The local reduction could be qualitatively sensed with WDX analysis and Auger line scans. An estimation of the film temperature in the beam center indicates that crystallization occurs at less than 150 degrees C, well below the atmospheric crystallization temperature of the present films. The high e-beam sensitivity in combination with the well-defined volume loss from oxygen desorption allows for precise electron lithographic topographical patterning of the present oxides. Irradiation effects leading to the observed reduction and crystallization phenomena under moderate electron energies are discussed.

  16. Faster in-plane switching and reduced rotational viscosity characteristics in a graphene-nematic suspension

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

    Basu, Rajratan, E-mail: basu@usna.edu; Kinnamon, Daniel; Skaggs, Nicole

    2016-05-14

    The in-plane switching (IPS) for a nematic liquid crystal (LC) was found to be considerably faster when the LC was doped with dilute concentrations of monolayer graphene flakes. Additional studies revealed that the presence of graphene reduced the rotational viscosity of the LC, permitting the nematic director to respond quicker in IPS mode on turning the electric field on. The studies were carried out with several graphene concentrations in the LC, and the experimental results coherently suggest that there exists an optimal concentration of graphene, allowing a reduction in the IPS response time and rotational viscosity in the LC. Abovemore » this optimal graphene concentration, the rotational viscosity was found to increase, and consequently, the LC no longer switched faster in IPS mode. The presence of graphene suspension was also found to decrease the LC's pretilt angle significantly due to the π-π electron stacking between the LC molecules and graphene flakes. To understand the π-π stacking interaction, the anchoring mechanism of the LC on a CVD grown monolayer graphene film on copper substrate was studied by reflected crossed polarized microscopy. Optical microphotographs revealed that the LC alignment direction depended on monolayer graphene's hexagonal crystal structure and its orientation.« less

  17. Staffing and structure of infection prevention and control programs.

    PubMed

    Stone, Patricia W; Dick, Andrew; Pogorzelska, Monika; Horan, Teresa C; Furuya, E Yoko; Larson, Elaine

    2009-06-01

    The nature of infection prevention and control is changing; however, little is known about current staffing and structure of infection prevention and control programs. Our objectives were to provide a snapshot of the staffing and structure of hospital-based infection prevention and control programs in the United States. A Web-based survey was sent to 441 hospitals that participate in the National Healthcare Safety Network. The response rate was 66% (n = 289); data were examined on 821 professionals. Infection preventionist (IP) staffing was significantly negatively related to bed size, with higher staffing in smaller hospitals (P < .001). Median staffing was 1 IP per 167 beds. Forty-seven percent of IPs were certified, and 24 percent had less than 2 years of experience. Most directors or hospital epidemiologists were reported to have authority to close beds for outbreaks always or most of the time (n = 225, 78%). Only 32% (n = 92) reported using an electronic surveillance system to track infections. This study is the first to provide a comprehensive description of current infection prevention and control staffing, organization, and support in a select group of hospitals across the nation. Further research is needed to identify effective staffing levels for various hospital types as well as examine how the IP role is changing over time.

  18. Staffing and structure of infection prevention and control programs

    PubMed Central

    Stone, Patricia W.; Dick, Andrew; Pogorzelska, Monika; Horan, Teresa C.; Furuya, E. Yoko; Larson, Elaine

    2009-01-01

    Background The nature of infection prevention and control is changing; however, little is known about current staffing and structure of infection prevention and control programs. Methods Our objectives were to provide a snapshot of the staffing and structure of hospital-based infection prevention and control programs in the United States. A Web-based survey was sent to 441 hospitals that participate in the National Healthcare Safety Network. Results The response rate was 66% (n = 289); data were examined on 821 professionals. Infection preventionist (IP) staffing was significantly negatively related to bed size, with higher staffing in smaller hospitals (P < .001). Median staffing was 1 IP per 167 beds. Forty-seven percent of IPs were certified, and 24 percent had less than 2 years of experience. Most directors or hospital epidemiologists were reported to have authority to close beds for outbreaks always or most of the time (n = 225, 78%). Only 32% (n = 92) reported using an electronic surveillance system to track infections. Conclusion This study is the first to provide a comprehensive description of current infection prevention and control staffing, organization, and support in a select group of hospitals across the nation. Further research is needed to identify effective staffing levels for various hospital types as well as examine how the IP role is changing over time. PMID:19201510

  19. Blind source computer device identification from recorded VoIP calls for forensic investigation.

    PubMed

    Jahanirad, Mehdi; Anuar, Nor Badrul; Wahab, Ainuddin Wahid Abdul

    2017-03-01

    The VoIP services provide fertile ground for criminal activity, thus identifying the transmitting computer devices from recorded VoIP call may help the forensic investigator to reveal useful information. It also proves the authenticity of the call recording submitted to the court as evidence. This paper extended the previous study on the use of recorded VoIP call for blind source computer device identification. Although initial results were promising but theoretical reasoning for this is yet to be found. The study suggested computing entropy of mel-frequency cepstrum coefficients (entropy-MFCC) from near-silent segments as an intrinsic feature set that captures the device response function due to the tolerances in the electronic components of individual computer devices. By applying the supervised learning techniques of naïve Bayesian, linear logistic regression, neural networks and support vector machines to the entropy-MFCC features, state-of-the-art identification accuracy of near 99.9% has been achieved on different sets of computer devices for both call recording and microphone recording scenarios. Furthermore, unsupervised learning techniques, including simple k-means, expectation-maximization and density-based spatial clustering of applications with noise (DBSCAN) provided promising results for call recording dataset by assigning the majority of instances to their correct clusters. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  20. Excision of a viral reprogramming cassette by delivery of synthetic Cre mRNA

    PubMed Central

    Loh, Yuin-Han; Yang, Jimmy Chen; De Los Angeles, Alejandro; Guo, Chunguang; Cherry, Anne; Rossi, Derrick J.; Park, In-Hyun; Daley, George Q.

    2012-01-01

    The generation of patient-specific induced pluripotent stem (iPS) cells provides an invaluable resource for cell therapy, in vitro modeling of human disease, and drug screening. To date, most human iPS cells have been generated with integrating retro- and lenti-viruses and are limited in their potential utility because residual transgene expression may alter their differentiation potential or induce malignant transformation. Alternatively, transgene-free methods using adenovirus and protein transduction are limited by low efficiency. This report describes a protocol for the generation of transgene-free human induced pluripotent stem cells using retroviral transfection of a single vector, which includes the coding sequences of human OCT4, SOX2, KLF4, and cMYC linked with picornaviral 2A plasmids. Moreover, after reprogramming has been achieved, this cassette can be removed using mRNA transfection of Cre recombinase. The method described herein to excise reprogramming factors with ease and efficiency facilitates the experimental generation and use of transgene-free human iPS cells. PMID:22605648

  1. Efficient biotechnological approach for lentiviral transduction of induced pluripotent stem cells.

    PubMed

    Zare, Mehrak; Soleimani, Masoud; Mohammadian, Mozhdeh; Akbarzadeh, Abolfazl; Havasi, Parvaneh; Zarghami, Nosratollah

    2016-01-01

    Induced pluripotent stem (iPS) cells are generated from differentiated adult somatic cells by reprogramming them. Unlimited self-renewal, and the potential to differentiate into any cell type, make iPS cells very promising candidates for basic and clinical research. Furthermore, iPS cells can be genetically manipulated for use as therapeutic tools. DNA can be introduced into iPS cells, using lentiviral vectors, which represent a helpful choice for efficient transduction and stable integration of transgenes. In this study, we compare two methods of lentiviral transduction of iPS cells, namely, the suspension method and the hanging drop method. In contrast to the conventional suspension method, in the hanging drop method, embryoid body (EB) formation and transduction occur concurrently. The iPS cells were cultured to form EBs, and then transduced with lentiviruses, using the conventional suspension method and the hanging drop method, to express miR-128 and green fluorescent protein (GFP). The number of transduced cells were assessed by fluorescent microscopy and flow cytometry. MTT assay and real-time PCR were performed to determine the cell viability and transgene expression, respectively. Morphologically, GFP+ cells were more detectable in the hanging drop method, and this finding was quantified by flow cytometric analysis. According to the results of the MTT assay, cell viability was considerably higher in the hanging drop method, and real-time PCR represented a higher relative expression of miR-128 in the iPS cells introduced with lentiviruses in drops. Altogether, it seems that lentiviral transduction of challenging iPS cells using the hanging drop method offers a suitable and sufficient strategy in their gene transfer, with less toxicity than the conventional suspension method.

  2. IP-FCM measures physiologic protein-protein interactions modulated by signal transduction and small-molecule drug inhibition.

    PubMed

    Smith, Stephen E P; Bida, Anya T; Davis, Tessa R; Sicotte, Hugues; Patterson, Steven E; Gil, Diana; Schrum, Adam G

    2012-01-01

    Protein-protein interactions (PPI) mediate the formation of intermolecular networks that control biological signaling. For this reason, PPIs are of outstanding interest in pharmacology, as they display high specificity and may represent a vast pool of potentially druggable targets. However, the study of physiologic PPIs can be limited by conventional assays that often have large sample requirements and relatively low sensitivity. Here, we build on a novel method, immunoprecipitation detected by flow cytometry (IP-FCM), to assess PPI modulation during either signal transduction or pharmacologic inhibition by two different classes of small-molecule compounds. First, we showed that IP-FCM can detect statistically significant differences in samples possessing a defined PPI change as low as 10%. This sensitivity allowed IP-FCM to detect a PPI that increases transiently during T cell signaling, the antigen-inducible interaction between ZAP70 and the T cell antigen receptor (TCR)/CD3 complex. In contrast, IP-FCM detected no ZAP70 recruitment when T cells were stimulated with antigen in the presence of the src-family kinase inhibitor, PP2. Further, we tested whether IP-FCM possessed sufficient sensitivity to detect the effect of a second, rare class of compounds called SMIPPI (small-molecule inhibitor of PPI). We found that the first-generation non-optimized SMIPPI, Ro-26-4550, inhibited the IL-2:CD25 interaction detected by IP-FCM. This inhibition was detectable using either a recombinant CD25-Fc chimera or physiologic full-length CD25 captured from T cell lysates. Thus, we demonstrate that IP-FCM is a sensitive tool for measuring physiologic PPIs that are modulated by signal transduction and pharmacologic inhibition.

  3. Phytic acid enhances the oral absorption of isorhamnetin, quercetin, and kaempferol in total flavones of Hippophae rhamnoides L.

    PubMed

    Xie, Yan; Luo, Huilin; Duan, Jingze; Hong, Chao; Ma, Ping; Li, Guowen; Zhang, Tong; Wu, Tao; Ji, Guang

    2014-03-01

    Total flavones of Hippophae rhamnoides L. (TFH) have a clinical use in the treatment of cardiac disease. The pharmacological effects of TFH are attributed to its major flavonoid components, isorhamnetin, kaempferol, and quercetin. However, poor oral bioavailability of these flavonoids limits the clinical applications of TFH. This study explores phytic acid (IP6) enhancement of the oral absorption in rats of isorhamnetin, kaempferol, and quercetin in TFH. In vitro Caco-2 cell experiments and in vivo pharmacokinetic studies were performed to investigate the effects of IP6. The aqueous solubility and lipophilicity of isorhamnetin, quercetin, and kaempferol were determined with and without IP6, and mucosal epithelial damage resulting from IP6 addition was evaluated by MTT assays and morphology observations. The Papp of isorhamnetin, kaempferol, and quercetin was improved 2.03-, 1.69-, and 2.11-fold in the presence of 333 μg/mL of IP6, respectively. Water solubility was increased 22.75-, 15.15-, and 12.86-fold for isorhamnetin, kaempferol, and quercetin, respectively, in the presence of 20mg/mL IP6. The lipophilicity of the three flavonoids was slightly decreased, but their hydrophilicity was increased after the addition of IP6 in the water phase as the logP values of isorhamnetin, kaempferol, and quercetin decreased from 2.38±0.12 to 1.64±0.02, from 2.57±0.20 to 2.01±0.04, and from 2.39±0.12 to 1.15±0.01, respectively. The absorption enhancement ratios were 3.21 for isorhamnetin, 2.98 for kaempferol, and 1.64 for quercetin with co-administration of IP6 (200 mg/kg) in rats. In addition, IP6 (200 mg/kg, oral) caused neither significant irritation to the rat intestines nor cytotoxicity (400 μg/mL) in Caco-2 cells. The oral bioavailability of isorhamnetin, kaempferol, and quercetin in TFH was enhanced by the co-administration of IP6. The main mechanisms are related to their enhanced aqueous solubility and permeability in the presence of IP6. In summary, IP6 is a potential absorption enhancer for pharmaceutical formulations that is both effective and safe. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. An interprofessional approach to shared decision making: an exploratory case study with family caregivers of one IP home care team.

    PubMed

    Légaré, France; Stacey, Dawn; Brière, Nathalie; Robitaille, Hubert; Lord, Marie-Claude; Desroches, Sophie; Drolet, Renée

    2014-07-02

    Within the context of an exploratory case study, the authors assessed the perceptions of family caregivers about the decision-making process regarding relocating their relative and about the applicability of an interprofessional approach to shared decision making (IP-SDM). They also assessed perceptions of health professionals and health managers about IP-SDM. From November 2010 to October 2011, we worked with one IP home care team dedicated to older adults (the case) from a large primary health care organization in Quebec City, Canada. We identified six of their clients who had faced a decision about whether to stay at home or move to a long-term care facility in the past year and interviewed their family caregivers. We explored the decision-making process they had experienced regarding relocating their relative and their perceptions about the applicability of IP-SDM in this context. Attitudes towards IP-SDM and potential barriers to this approach were explored using a focus group with the participating IP home care team, individual interviews with 8 managers and a survey of 272 health professionals from the primary care organization. A hybrid process of inductive and deductive thematic analysis was used and data were triangulated across all sources. Family caregivers reported lack of agreement on the nature of the decision to be made, a disconnection between home care services and relatives' needs, and high cost of long-term care alternatives. Factors influencing their decision included their ability to provide care for their relative. While they felt somewhat supported by the IP home care team, they also felt pressured in the decision. Overall, they did not perceive they had been exposed to IP-SDM but agreed that it was applicable in this context. Results from the survey, focus group and interviews with health professionals and managers indicated they all had a favourable attitude towards IP-SDM but many barriers hampered its implementation in their practice. The family caregivers in this study did not experience IP-SDM when relocating their relative. Added to results obtained with health professionals and managers, this highlights the need for an effective intervention targeting identified barriers to implementing IP-SDM in this context.

  5. Integrating Intellectual Property Concepts into MIS Education: An Empirical Assessment

    ERIC Educational Resources Information Center

    Mykytyn, Peter P., Jr.; Mykytyn, Kathleen; Harrison, David A.

    2005-01-01

    The evolving legal environment surrounding intellectual property (IP) and its impact on information systems, especially involving electronic commerce, and the type of education and training provided by management information systems (MIS) faculty to MIS students is a relationship that has not been investigated. Although organizations are…

  6. The Internet and Education: Some Lessons on Privacy and Pitfalls.

    ERIC Educational Resources Information Center

    Descy, Don E.

    1997-01-01

    Most users have misconceptions about how the Internet works. Provides a brief history of the Internet and Transmission Control Protocol/Internet Protocol (TCP/IP); discusses electronic mail, privacy, and voluntary and involuntary information gathering; and contrasts the Internet and libraries, focusing on the Internet's lack of consistent…

  7. The Worldwide Interplanetary Scintillation (IPS) Stations (WIPSS) Network October 2016 Observing Campaign: Initial WIPSS Data Analyses

    NASA Astrophysics Data System (ADS)

    Bisi, M. M.; Fallows, R. A.; Jackson, B. V.; Tokumaru, M.; Gonzalez-Esparza, A.; Morgan, J.; Chashei, I. V.; Mejia-Ambriz, J.; Tyul'bashev, S. A.; Manoharan, P. K.; De la Luz, V.; Aguilar-Rodriguez, E.; Yu, H. S.; Barnes, D.; Chang, O.; Odstrcil, D.; Fujiki, K.; Shishov, V.

    2017-12-01

    Interplanetary Scintillation (IPS) allows for the determination of velocity and a proxy for plasma density to be made throughout the corona and inner heliosphere. Where sufficient observations are undertaken, the results can be used as input to the University of California, San Diego (UCSD) three-dimensional (3-D) time-dependent tomography suite to allow for the full 3-D reconstruction of both velocity and density throughout the inner heliosphere. By combining IPS results from multiple observing locations around the planet, we can increase both the temporal and spatial coverage across the whole of the inner heliosphere and hence improve forecast capability. During October 2016, a unique opportunity arose whereby the European-based LOw Frequency ARray (LOFAR) radio telescope was used to make nearly four weeks of continuous observations of IPS as a heliospheric space-weather trial campaign. This was expanded into a global effort to include observations of IPS from the Murchison Widefield Array (MWA) in Western Australia and many more observations from various IPS-dedicated WIPSS Network systems. LOFAR is a next-generation low-frequency radio interferometer capable of observing in the radio frequency range 10-250 MHz, nominally with up to 80 MHz bandwidth at a time. MWA in Western Australia is capable of observing in the 80-300 MHz frequency range nominally using up to 32 MHz of bandwidth. IPS data from LOFAR, ISEE, the MEXican Array Radio Telescope (MEXART), and, where possible, other WIPSS Network systems (such as LPI-BSA and Ooty), will be used in this study and we will present some initial findings for these data sets. We also make a first attempt at the 3-D reconstruction of multiple pertinent WIPSS results in the UCSD tomography. We will also try to highlight some of the potential future tools that make LOFAR a very unique system to be able to test and validate a whole plethora of IPS analysis methods with the same set of IPS data.

  8. Identification and characterization of novel IGFBP5 interacting protein: evidence IGFBP5-IP is a potential regulator of osteoblast cell proliferation

    PubMed Central

    Amaar, Yousef G.; Tapia, Blanca; Chen, Shin-Tai; Baylink, David J.; Mohan, Subburaman

    2010-01-01

    Insulin-like growth factor binding protein-5 (IGFBP5) is a multifunctional protein, which acts not only as a traditional binding protein, but also functions as a growth factor independent of IGFs to stimulate bone formation. It has been predicted that the intrinsic growth factor action of IGFBP5 involves binding of IGFBP5 to a putative receptor to induce downstream signaling pathways and/or nuclear translocation of IGFBP5 to influence transcription of genes involved in osteoblast cell proliferation/differentiation. Our study indentified proteins that bound to IGFBP5 using IGFBP5 as bait in a yeast two-hybrid screen of the U2 human osteosarcoma cell cDNA library. One of the clones that interacted strongly with the bait under high-stringency conditions corresponded to a novel IGFBP5 interacting protein (IGFBP5-IP) encoded by a gene that resides in mouse chromosome 10. The interaction between IGFBP5-IP and IGFBP5 is confirmed by in vitro coimmunoprecipitation studies that used pFlag and IGFBP5 polyclonal antibody, and cell lysates overexpressing both IGFBP5-IP and IGFBP5. Northern blot and RT-PCR analysis showed that the IGFBP-IP is expressed in both untransformed normal human osteoblasts and in osteosarcoma cell lines, which are known to produce IGFBP5. To determine the roles of IGFBP5-IP, we evaluated the effect of blocking the expression of IGFBP5-IP on osteoblast proliferation. We found that using a IGFBP5-IP-specific small interfering-hairpin plasmid resulted in a decrease in both basal and IGFBP5-induced osteoblast cell proliferation. On the basis of these findings, we predict that IGFBP5-IP may act as intracellular mediator of growth promoting actions of IGFBP5 and perhaps other osteoregulatory agents in bone cells. PMID:16269403

  9. A Simple Method to Quantitate IP-10 in Dried Blood and Plasma Spots

    PubMed Central

    Aabye, Martine G.; Eugen-Olsen, Jesper; Werlinrud, Anne Marie; Holm, Line Lindebo; Tuuminen, Tamara; Ravn, Pernille; Ruhwald, Morten

    2012-01-01

    Background Antigen specific release of IP-10 is an established marker for infection with M.tuberculosis. Compared to IFN-γ, IP-10 is released in 100-fold higher concentrations enabling the development of novel assays for detection. Dried blood spots are a convenient sample for high throughput newborn screening. Aim To develop a robust and sensitive ELISA-based assay for IP-10 detection in plasma, dried blood spots (DBS) and dried plasma spots (DPS); to validate the ELISA in clinically relevant samples; and to assess the performance of the assay for detection of Cytomegalovirus (CMV) and M.tuberculosis specific immune responses. Method We raised mice and rat monoclonal antibodies against human IP-10 and developed an ELISA. The assay was validated and applied to the detection of CMV and M.tuberculosis specific responses in 18 patients with immune reactivity towards M.tuberculosis and 32 healthy controls of which 22 had immune reactivity towards CMV and none towards M.tuberculosis. We compared the performance of this new assay to IFN-γ. Results The ELISA was reliable for IP-10 detection in both plasma and filter paper samples. The linear range of the ELISA was 2.5–600 pg/ml. IFN-γ was not readily detectable in DPS samples. IP-10 was stabile in filter paper samples for at least 4 weeks at 37°C. The correlation between IP-10 detected in plasma, DPS and DBS samples was excellent (r2>0.97). Conclusions This newly developed assay is reliable for IP-10 quantification in plasma, DBS and DPS samples from antigen stimulated and non-stimulated whole blood. The filter paper assays enable easy sample acquisition and transport at ambient temperature e.g. via the postal system. The system can potentially simplify diagnostic assays for M.tuberculosis and CMV infection. PMID:22761744

  10. Power Balance Modeling and Validation for ST Startup Using Local Helicity Injection

    NASA Astrophysics Data System (ADS)

    Barr, J. L.; Bodner, G. M.; Bongard, M. W.; Burke, M. G.; Fonck, R. J.; Hinson, E. T.; Perry, J. M.; Reusch, J. A.; Schlossberg, D. J.

    2015-11-01

    Local Helicity Injection (LHI) uses localized current injectors for routine Ip<0.18 MA non-solenoidal startup on the Pegasus ST. A power-balance model is under development for predictive Ip t using helicity-balance to quantify LHI's effective current drive, Veff. Analytic formulas for low-A plasma inductance and vertical field are used to account for the inductive effects of dynamic shape evolution. These formulas are being validated against magnetic reconstructions of LHI discharges with varied shape evolutions. Initial results match experimental Ip t within 20 kA with assumed shaping and average resistivity (Spitzer, Te = 60 eV). Geometric effects and inductive drive provide 2.0 V along with Veff = 0.3 V to balance 1.1 V of resistive losses and 1.2 V inductive reactance to ramping Ip. The model is especially sensitive to resistivity when Te<150 eV. Initial Thomson Scattering results give core Te = 72 +/-22 eV, and at times suggest higher central electron energies. Spatial and temporal scans are underway to quantify LHI plasma resistivity and transport. MA-class startup in NSTX-U will require increased area (Ainj >= 40 cm2) LHI systems that play a larger role in current drive than geometric effects, with Veff dropping from >10 V to on-par with inductive effects. This regime is accessed in Pegasus at Ip ≅ 300 kA. Work supported by US DOE grants DE-FG02-96ER54375 and DE-SC0006928.

  11. Overview of Non-Solenoidal Startup Studies in the Pegasus ST

    NASA Astrophysics Data System (ADS)

    Bongard, M. W.; Barr, J. L.; Bodner, G. M.; Burke, M. G.; Fonck, R. J.; Pachicano, J. L.; Perry, J. M.; Reusch, J. A.; Richner, N. J.; Rodriguez Sanchez, C.; Schlossberg, D. J.

    2016-10-01

    Local helicity injection (LHI) is a non-solenoidal startup method pursued on Pegasus utilizing compact, high power current sources (Ainj 2 - 4 cm2, Iinj 10 kA, Vinj 1 kV) at the plasma edge. Outboard injectors (Ninj = 4 , Ainj = 8 cm2) produce Ip 170 kA plasmas compatible with Ohmic drive. A 0-D model that treats the plasma as a resistive element with time-varying inductance and enforces Ip limits from Taylor relaxation is used to interpret experimental Ip(t) in several scenarios. Strong inductive drive arises from the plasma shape evolution, in addition to poloidal field induction. A new injector system has recently been installed in the lower divertor region (Ninj = 2 , Ainj = 8 cm2) to explore the implications of geometric placement of the helicity injectors on LHI startup. This geometry supports tests of reconnection dynamics seen in NIMROD simulations, high-BT effects expected in larger devices, and LHI electron confinement with and without inductive assist. Plasmas with Ip > 130 kA, Vinj 0.5 kV, Δtpulse 8 ms and BT /BT , max <= 50 % are produced with the inboard system to date, consistent with performance expectations. Higher Ip is expected with increased BT, Vinj, and Δtpulse . Thomson scattering data in both geometries indicate high Te >= 100 eV during LHI, suggesting the confinement is not strongly stochastic. Conceptual design work is exploring the feasibility of coaxial helicity injection and ECH heating on Pegasus in addition to LHI. Work supported by US DOE Grant DE-FG02-96ER54375.

  12. Systemic synergism between codeine and morphine in three pain models in mice.

    PubMed

    Miranda, Hugo F; Noriega, Viviana; Zepeda, Ramiro J; Sierralta, Fernando; Prieto, Juan C

    2013-01-01

    The combination of two analgesic agents offers advantages in pain treatment. Codeine and morphine analgesia is due to activation of opioid receptor subtypes. This study, performed in mice using isobolographic analysis, evaluated the type of interaction in intraperitoneal (ip) or intrathecal (it) coadministration of codeine and morphine, in three nociceptive behavioral models. Intrathecal morphine resulted to be 7.5 times more potent than ip morphine in the writhing test, 55.6 times in the tail flick test and 1.7 times in phase II of the orofacial formalin test; however, in phase I of the same test ip was 1.2 times more potent than it morphine. Intrathecal codeine resulted being 3.4 times more potent than ip codeine in the writhing test, 1.6 times in the tail flick test, 2.5 times in phase I and 6.7 times in phase II of the orofacial formalin test. Opioid coadministration had a synergistic effect in the acute tonic pain (acetic acid writhing test), acute phasic pain (tail flick test) and inflammatory pain (orofacial formalin test). The interaction index ranged between 0.284 (writhing ip) and 0.440 (orofacial formalin phase II ip). This synergy may relate to the different pathways of pain transmission and to the different intracellular signal transduction. The present findings also raise the possibility of potential clinical advantages in combining opioids in pain management.

  13. Different SEP recovery cycle in adolescent migraineurs with exploding or imploding pain.

    PubMed

    Iacovelli, Elisa; Tarantino, Samuela; Capuano, Alessandro; De Luca, Massimiliano; De Ranieri, Cristiana; Vigevano, Federico; Arendt-Nielsen, Lars; Valeriani, Massimiliano

    2013-01-01

    Our aim was to investigate whether migraine adolescents with pain directed inside (imploding pain--IP) and outside (exploding pain--EP) the head may have different levels of cortical excitability underlying their migraineous syndrome. Ten migraine children referring prevalent EP (mean age 14.5 ± 1.4 years, 3 girls, 7 boys), 10 patients with IP (mean age 14.1 ± 2.2 years, 4 girls, 6 boys), and 13 control subjects (mean age 13 ± 1.8 years, 6 males, 7 females) participated to the study. The recovery cycle of the somatosensory evoked potentials to electrical median nerve stimuli at interstimulus intervals of 5, 20, and 40 ms was measured. Anger expression, anxiety, and somatic concerns were investigated in migraine patients. Overall, SEP recovery cycle was shorter in migraineurs than in healthy controls. The recovery cycle of the frontal N30 SEP component was significantly shorter in IP than in EP patients. While among the EP patients those with faster N30 recovery cycle had higher Trait-Anger score, the opposite was found among the IP patients. Our results suggest that the inhibitory mechanisms within the somatosensory cortex are more impaired in IP than in EP migraine adolescents. The pathophysiological difference between IP and EP migraineurs was strengthened also by the opposite correlations between the brain excitability and the anger expression. Copyright © 2013 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  14. Infection prevention workforce: Potential benefits to educational diversity.

    PubMed

    Reese, Sara M; Gilmartin, Heather M

    2017-06-01

    Nurses have historically occupied the infection preventionist (IP) role. As the knowledge and skills needed to advance the field expand, professionals from public health and the laboratory sciences have become IPs. Our study describes the characteristics of current IPs and assesses for relationships between background, certification, experience, and type of work performed. The data were drawn from an existing dataset collected in the conduct of the Association for Professionals in Infection Control and Epidemiology (APIC) MegaSurvey. Descriptive statistics were computed. Associations were calculated using χ 2 or Cochran-Mantel-Haenszel tests. Characteristics of IPs were stratified by work-related activities to allow for comparisons between groups. Of the 13,050 active APIC members, 4,079 participated in the survey (31% response rate). The primary job activity for nurses (97.9%; n = 2,434) was preventing and controlling the transmission of infectious agents or health care-associated infections, for laboratory scientists (97.5%; n = 307) it was the interpretation of surveillance data, and for public health professionals (96.1%; n = 136) it was management and communication: feedback. Infection control departments would benefit from hiring IPs with diverse education and training to address the expanding roles and responsibilities of IPs. This may facilitate the implementation of novel and innovative processes that will impact patient care. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. All rights reserved.

  15. Modulation of A-type potassium channels by a family of calcium sensors.

    PubMed

    An, W F; Bowlby, M R; Betty, M; Cao, J; Ling, H P; Mendoza, G; Hinson, J W; Mattsson, K I; Strassle, B W; Trimmer, J S; Rhodes, K J

    2000-02-03

    In the brain and heart, rapidly inactivating (A-type) voltage-gated potassium (Kv) currents operate at subthreshold membrane potentials to control the excitability of neurons and cardiac myocytes. Although pore-forming alpha-subunits of the Kv4, or Shal-related, channel family form A-type currents in heterologous cells, these differ significantly from native A-type currents. Here we describe three Kv channel-interacting proteins (KChIPs) that bind to the cytoplasmic amino termini of Kv4 alpha-subunits. We find that expression of KChIP and Kv4 together reconstitutes several features of native A-type currents by modulating the density, inactivation kinetics and rate of recovery from inactivation of Kv4 channels in heterologous cells. All three KChIPs co-localize and co-immunoprecipitate with brain Kv4 alpha-subunits, and are thus integral components of native Kv4 channel complexes. The KChIPs have four EF-hand-like domains and bind calcium ions. As the activity and density of neuronal A-type currents tightly control responses to excitatory synaptic inputs, these KChIPs may regulate A-type currents, and hence neuronal excitability, in response to changes in intracellular calcium.

  16. Anomalous diffusion of Ibuprofen in cyclodextrin nanosponge hydrogels: an HRMAS NMR study

    PubMed Central

    Ferro, Monica; Punta, Carlo; Melone, Lucio; Panzeri, Walter; Rossi, Barbara; Trotta, Francesco

    2014-01-01

    Summary Ibuprofen sodium salt (IP) was encapsulated in cyclodextrin nanosponges (CDNS) obtained by cross-linking of β-cyclodextrin with ethylenediaminetetraacetic acid dianhydride (EDTAn) in two different preparations: CDNSEDTA 1:4 and 1:8, where the 1:n notation indicates the CD to EDTAn molar ratio. The entrapment of IP was achieved by swelling the two polymers with a 0.27 M solution of IP in D2O, leading to colourless, homogeneous hydrogels loaded with IP. The molecular environment and the transport properties of IP in the hydrogels were studied by high resolution magic angle spinning (HRMAS) NMR spectroscopy. The mean square displacement (MSD) of IP in the gels was obtained by a pulsed field gradient spin echo (PGSE) NMR pulse sequence at different observation times t d. The MSD is proportional to the observation time elevated to a scaling factor α. The α values define the normal Gaussian random motion (α = 1), or the anomalous diffusion (α < 1, subdiffusion, α > 1 superdiffusion). The experimental data here reported point out that IP undergoes subdiffusive regime in CDNSEDTA 1:4, while a slightly superdiffusive behaviour is observed in CDNSEDTA 1:8. The transition between the two dynamic regimes is triggered by the polymer structure. CDNSEDTA 1:4 is characterized by a nanoporous structure able to induce confinement effects on IP, thus causing subdiffusive random motion. CDNSEDTA 1:8 is characterized not only by nanopores, but also by dangling EDTA groups ending with ionized COO− groups. The negative potential provided by such groups to the polymer backbone is responsible for the acceleration effects on the IP anion thus leading to the superdiffusive behaviour observed. These results point out that HRMAS NMR spectroscopy is a powerful direct method for the assessment of the transport properties of a drug encapsulated in polymeric scaffolds. The diffusion properties of IP in CDNS can be modulated by suitable polymer synthesis; this finding opens the possibility to design suitable systems for drug delivery with predictable and desired drug release properties. PMID:25550735

  17. Ionization energies and electron affinities from a random-phase-approximation many-body Green's-function method including exchange interactions

    NASA Astrophysics Data System (ADS)

    Heßelmann, Andreas

    2017-06-01

    A many-body Green's-function method employing an infinite order summation of ring and exchange-ring contributions to the self-energy is presented. The individual correlation and relaxation contributions to the quasiparticle energies are calculated using an iterative scheme which utilizes density fitting of the particle-hole, particle-particle and hole-hole densities. It is shown that the ionization energies and electron affinities of this approach agree better with highly accurate coupled-cluster singles and doubles with perturbative triples energy difference results than those obtained with second-order Green's-function approaches. An analysis of the correlation and relaxation terms of the self-energy for the direct- and exchange-random-phase-approximation (RPA) Green's-function methods shows that the inclusion of exchange interactions leads to a reduction of the two contributions in magnitude. These differences, however, strongly cancel each other when summing the individual terms to the quasiparticle energies. Due to this, the direct- and exchange-RPA methods perform similarly for the description of ionization energies (IPs) and electron affinities (EAs). The coupled-cluster reference IPs and EAs, if corrected to the adiabatic energy differences between the neutral and charged molecules, were shown to be in very good agreement with experimental measurements.

  18. State of the Art of Interpersonal Physiology in Psychotherapy: A Systematic Review.

    PubMed

    Kleinbub, Johann R

    2017-01-01

    Introduction: The fast expanding field of Interpersonal Physiology (IP) focuses on the study of co-ordination or synchronization dynamics between the physiological activities of two, or more, individuals. IP has been associated with various relational features (e.g., empathy, attachment security, rapport, closeness…) that overlap with desirable characteristics of clinical relationships, suggesting that the relevant studies might provide objective, economical, and theory-free techniques to investigate the clinical process. The goal of the present work is to systematically retrieve and review the literature on IP in the field of psychotherapy and psychological intervention, in order to consolidate the knowledge of this research domain, highlight its critical issues, and delineate possible developments. Method: Following the guidelines by Okoli and Schabram (2010), a systematic literature search was performed in Scopus, Web of Science, PsycINFO, and PubMed databases by means of multiple keyword combinations; the results were integrated with references to the retrieved articles' bibliography as well as to other published reviews on IP. Results: All the retrieved documents reported clinical interactions that are characterized, at least partially, by IP phenomena. They appear to use fragmented and sometimes ambiguous terminology and show a lack of both specific theory-informed hypotheses and sound analytical procedures. Conclusion: Although the psychological nature of IP and its role in the clinical relationship are still mostly unknown, the potential value of a physiology-based measure of implicit exchanges in psychotherapy drives an acceleration in this research field. On the basis of the highlighted critical issues, possible future directions for clinical IP researchers are discussed.

  19. Informing the Design and Evaluation of Superuser Care Management Initiatives: Accounting for Regression-to-the-Mean.

    PubMed

    Chakravarty, Sujoy; Cantor, Joel C

    2016-09-01

    Health care spending is concentrated among a small number of high-cost patients, and the popularity of initiatives to improve care and reduce cost among such "superusers" (SUs) is growing. However, SU costs decline naturally over time, even without intervention, a statistical phenomenon known as regression-to-the-mean (RTM). We assess the magnitude of RTM in hospital costs for cohorts of hospital SUs identified on the basis of high inpatient (IP) or emergency department (ED) utilization. We further examine how cost and RTM are associated with patient characteristics including behavioral health (BH) problems, multiple chronic conditions, and indicators of vulnerability. Using longitudinally linked all-payer hospital billing data, we selected patient cohorts with ≥2 IP stays (IP SUs) or ≥6 ED visits (ED SUs) during a 6-month baseline period, and additional subgroups defined by combinations of IP and ED superuse. A total of 289,060 NJ hospital IP and treat-and-release ED patients over 2009-2011. Hospital costs among IP and ED SUs declined 70% and 38%, respectively, over 8 quarters following the baseline period. The decrease occurs more quickly for IP SUs compared with ED SUs. Presence of BH problems was positively associated with costs among patients overall, but the relationship varied by SU cohort. Understanding patterns of RTM among SU populations is important for designing intervention strategies, as there is greater potential for savings among patients with more persistent costs (less RTM). Further, as many SU initiatives lack resources for rigorous evaluation, quantifying the extent of RTM is vital for interpreting program outcomes.

  20. Nasal oxytocin administration reduces food intake without affecting locomotor activity and glycemia with c-Fos induction in limited brain areas.

    PubMed

    Maejima, Yuko; Rita, Rauza Sukma; Santoso, Putra; Aoyama, Masato; Hiraoka, Yuichi; Nishimori, Katsuhiko; Gantulga, Darambazar; Shimomura, Kenju; Yada, Toshihiko

    2015-01-01

    Recent studies have considered oxytocin (Oxt) as a possible medicine to treat obesity and hyperphagia. To find the effective and safe route for Oxt treatment, we compared the effects of its nasal and intraperitoneal (IP) administration on food intake, locomotor activity, and glucose tolerance in mice. Nasal Oxt administration decreased food intake without altering locomotor activity and increased the number of c-Fos-immunoreactive (ir) neurons in the paraventricular nucleus (PVN) of the hypothalamus, the area postrema (AP), and the dorsal motor nucleus of vagus (DMNV) of the medulla. IP Oxt administration decreased food intake and locomotor activity and increased the number of c-Fos-ir neurons not only in the PVN, AP, and DMNV but also in the nucleus of solitary tract of the medulla and in the arcuate nucleus of the hypothalamus. In IP glucose tolerance tests, IP Oxt injection attenuated the rise of blood glucose, whereas neither nasal nor intracerebroventricular Oxt affected blood glucose. In isolated islets, Oxt administration potentiated glucose-induced insulin secretion. These results indicate that both nasal and IP Oxt injections reduce food intake to a similar extent and increase the number of c-Fos-ir neurons in common brain regions. IP Oxt administration, in addition, activates broader brain regions, reduces locomotor activity, and affects glucose tolerance possibly by promoting insulin secretion from pancreatic islets. In comparison with IP administration, the nasal route of Oxt administration could exert a similar anorexigenic effect with a lesser effect on peripheral organs. © 2015 S. Karger AG, Basel.

  1. Endopolysaccharides from Ganoderma resinaceum, Phlebia rufa, and Trametes versicolor affect differently the proliferation rate of HepG2 cells.

    PubMed

    Silva, Amélia M; Miranda, Andreia; Fernandes, Elisabete; Santos, Susana; Fraga, Irene; Santos, Dario L; Dias, Albino A; Bezerra, Rui M

    2013-03-01

    Fungi have been used for medicinal purposes for long time by Asian countries, being a putative source of powerful new phytopharmaceuticals such as polysaccharides. The aim of this study was to extract endopolysaccharides (IPS) from Ganoderma resinaceum, Phlebia rufa, and Trametes versicolor, grown under submerged culture, to compare crude IPS production, total carbohydrate, and protein yield, and to study the effect of these IPS on HepG2 cells proliferation rate. Total biomass produced by G. resinaceum, P. rufa, and T. versicolor was (in gram per liter) 3.32 ± 0.80, 5.42 ± 0.58, and 4.2 ± 1.29 and the IPS yield (as the biomass percent) was 9.9 ± 0.05, 29.0 ± 6.3, and 9.1 ± 3.1 %, respectively. Characterization of IPS has shown different proportion between total sugar and protein being, on average 6.04, 10.74, and 22.62, for G. resinaceum, T. versicolor, and P. rufa, respectively. The IPS effect, at 50, 100, and 200 μg mL(-1) on HepG2 cell growth and viability was negligible for G. resinaceum and P. rufa but, in the case of T. versicolor, 200 μg mL(-1) of IPS evoked 40 % reduction on cell growth. The results suggest that the intracellular polysaccharides from T. versicolor are a potential source for bioactive molecules with anti-proliferative properties.

  2. Cell Penetrating Peptides and Cationic Antibacterial Peptides

    PubMed Central

    Rodriguez Plaza, Jonathan G.; Morales-Nava, Rosmarbel; Diener, Christian; Schreiber, Gabriele; Gonzalez, Zyanya D.; Lara Ortiz, Maria Teresa; Ortega Blake, Ivan; Pantoja, Omar; Volkmer, Rudolf; Klipp, Edda; Herrmann, Andreas; Del Rio, Gabriel

    2014-01-01

    Cell penetrating peptides (CPP) and cationic antibacterial peptides (CAP) have similar physicochemical properties and yet it is not understood how such similar peptides display different activities. To address this question, we used Iztli peptide 1 (IP-1) because it has both CPP and CAP activities. Combining experimental and computational modeling of the internalization of IP-1, we show it is not internalized by receptor-mediated endocytosis, yet it permeates into many different cell types, including fungi and human cells. We also show that IP-1 makes pores in the presence of high electrical potential at the membrane, such as those found in bacteria and mitochondria. These results provide the basis to understand the functional redundancy of CPPs and CAPs. PMID:24706763

  3. Reference Maps of Human ES and iPS Cell Variation Enable High-Throughput Characterization of Pluripotent Cell Lines

    PubMed Central

    Bock, Christoph; Kiskinis, Evangelos; Verstappen, Griet; Gu, Hongcang; Boulting, Gabriella; Smith, Zachary D.; Ziller, Michael; Croft, Gist F.; Amoroso, Mackenzie W.; Oakley, Derek H.; Gnirke, Andreas; Eggan, Kevin; Meissner, Alexander

    2011-01-01

    SUMMARY The developmental potential of human pluripotent stem cells suggests that they can produce disease-relevant cell types for biomedical research. However, substantial variation has been reported among pluripotent cell lines, which could affect their utility and clinical safety. Such cell-line-specific differences must be better understood before one can confidently use embryonic stem (ES) or induced pluripotent stem (iPS) cells in translational research. Toward this goal we have established genome-wide reference maps of DNA methylation and gene expression for 20 previously derived human ES lines and 12 human iPS cell lines, and we have measured the in vitro differentiation propensity of these cell lines. This resource enabled us to assess the epigenetic and transcriptional similarity of ES and iPS cells and to predict the differentiation efficiency of individual cell lines. The combination of assays yields a scorecard for quick and comprehensive characterization of pluripotent cell lines. PMID:21295703

  4. An End-to-End Loss Discrimination Scheme for Multimedia Transmission over Wireless IP Networks

    NASA Astrophysics Data System (ADS)

    Zhao, Hai-Tao; Dong, Yu-Ning; Li, Yang

    As the rapid growth of wireless IP networks, wireless IP access networks have a lot of potential applications in a variety of fields in civilian and military environments. Many of these applications, such as realtime audio/video streaming, will require some form of end-to-end QoS assurance. In this paper, an algorithm WMPLD (Wireless Multimedia Packet Loss Discrimination) is proposed for multimedia transmission control over wired-wireless hybrid IP networks. The relationship between packet length and packet loss rate in the Gilbert wireless error model is investigated. Furthermore, the algorithm can detect the nature of packet losses by sending large and small packets alternately, and control the sending rate of nodes. In addition, by means of updating factor K, this algorithm can adapt to the changes of network states quickly. Simulation results show that, compared to previous algorithms, WMPLD algorithm can improve the networks throughput as well as reduce the congestion loss rate in various situations.

  5. Efficacy of bacteriophage therapy in a model of Burkholderia cenocepacia pulmonary infection

    PubMed Central

    Carmody, Lisa A.; Gill, Jason J.; Summer, Elizabeth J.; Sajjan, Uma S.; Gonzalez, Carlos F.; Young, Ryland F.; LiPuma, John J.

    2009-01-01

    The therapeutic potential of bacteriophage (phage) in a mouse model of acute B. cenocepacia pulmonary infection was assessed. Phage were administered by either intranasal (i.n.) inhalation or intraperitoneal (i.p.) injection. Bacterial density, macrophage inflammatory protein-2 (MIP-2), and tumor necrosis factor-α (TNFα) levels were significantly reduced in lungs of mice treated with i.p. phage. No significant differences in lung bacterial density or MIP-2 levels were found between untreated mice and mice treated with i.n. phage, i.p. UV-inactivated phage, or i.p. λ phage controls. Mock-infected mice treated with phage showed no significant increase in lung MIP-2 or TNFα levels compared to mock-infected / mock-treated mice. We have demonstrated the efficacy of phage therapy in an acute B. cenocepacia lung infection model. Systemic administration of phage was more effective than inhalational administration, suggesting that circulating phage have better access to bacteria in lung compared to topical phage. PMID:20001604

  6. Induced Pluripotent Stem Cell-Derived Red Blood Cells and Platelet Concentrates: From Bench to Bedside.

    PubMed

    Focosi, Daniele; Amabile, Giovanni

    2017-12-27

    Red blood cells and platelets are anucleate blood components indispensable for oxygen delivery and hemostasis, respectively. Derivation of these blood elements from induced pluripotent stem (iPS) cells has the potential to develop blood donor-independent and genetic manipulation-prone products to complement or replace current transfusion banking, also minimizing the risk of alloimmunization. While the production of erythrocytes from iPS cells has challenges to overcome, such as differentiation into adult-type phenotype that functions properly after transfusion, platelet products are qualitatively and quantitatively approaching a clinically-applicable level owing to advances in expandable megakaryocyte (MK) lines, platelet-producing bioreactors, and novel reagents. Guidelines that assure the quality of iPS cells-derived blood products for clinical application represent a novel challenge for regulatory agencies. Considering the minimal risk of tumorigenicity and the expected significant demand of such products, ex vivo production of iPS-derived blood components can pave the way for iPS translation into the clinic.

  7. An interactive environment for agile analysis and visualization of ChIP-sequencing data.

    PubMed

    Lerdrup, Mads; Johansen, Jens Vilstrup; Agrawal-Singh, Shuchi; Hansen, Klaus

    2016-04-01

    To empower experimentalists with a means for fast and comprehensive chromatin immunoprecipitation sequencing (ChIP-seq) data analyses, we introduce an integrated computational environment, EaSeq. The software combines the exploratory power of genome browsers with an extensive set of interactive and user-friendly tools for genome-wide abstraction and visualization. It enables experimentalists to easily extract information and generate hypotheses from their own data and public genome-wide datasets. For demonstration purposes, we performed meta-analyses of public Polycomb ChIP-seq data and established a new screening approach to analyze more than 900 datasets from mouse embryonic stem cells for factors potentially associated with Polycomb recruitment. EaSeq, which is freely available and works on a standard personal computer, can substantially increase the throughput of many analysis workflows, facilitate transparency and reproducibility by automatically documenting and organizing analyses, and enable a broader group of scientists to gain insights from ChIP-seq data.

  8. Improvement of density resolution in short-pulse hard x-ray radiographic imaging using detector stacks

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

    Borm, B.; Gärtner, F.; Khaghani, D.

    2016-09-15

    We demonstrate that stacking several imaging plates (IPs) constitutes an easy method to increase hard x-ray detection efficiency. Used to record x-ray radiographic images produced by an intense-laser driven hard x-ray backlighter source, the IP stacks resulted in a significant improvement of the radiograph density resolution. We attribute this to the higher quantum efficiency of the combined detectors, leading to a reduced photon noise. Electron-photon transport simulations of the interaction processes in the detector reproduce the observed contrast improvement. Increasing the detection efficiency to enhance radiographic imaging capabilities is equally effective as increasing the x-ray source yield, e.g., by amore » larger drive laser energy.« less

  9. Practice makes perfect: A systematic review of the expertise development of pharmacist and nurse independent prescribers in the United Kingdom.

    PubMed

    Abuzour, Aseel S; Lewis, Penny J; Tully, Mary P

    2018-01-01

    Prescribing is a complex and error-prone task that demands expertise. McLellan et al.'s theory of expertise development model ("the model"), developed to assess medical literature on prescribing by medical students, proposes that in order to develop, individuals should deliberately engage their knowledge, skills and attitudes within a social context. Its applicability to independent prescribers (IP) is unknown. A systematic review was conducted to explore whether the model is applicable to non-medical independent prescribing and to assess the factors underpinning expertise development reported in the literature. Six electronic databases (EMBASE, Medline, AMED, CINAHL, IPA and PsychInfo) were searched for articles published between 2006 and 2016, reporting empirical data on pharmacist and nurse IPs education or practice. Data were extracted using themes from the model and analysed using framework analysis. Thirty-four studies met the inclusion criteria. Knowledge, pre-registration education, experience, support and confidence were some of the intrinsic and extrinsic factors influencing IPs. Difficulty in transferring theory to practice was attributed to lack of basic pharmacology and bioscience content in pre-registration nursing rather than the prescribing programme. Students saw interventions using virtual learning or learning in practice as more useful with long-term benefits e.g. students were able to use their skills in history taking following the virtual learning intervention 6-months after the programme. All studies demonstrated how engaging knowledge and skills affected individuals' attitude by, for example, increasing professional dignity. IPs were able to develop their expertise when integrating their competencies in a workplace context with support from colleagues and adherence to guidelines. This is the first study to synthesize data systematically on expertise development from studies on IPs using the model. The model showed the need for stronger foundations in scientific knowledge amongst some IPs, where continuous workplace practice can improve skills and strengthen attitudes. This could facilitate a smoother transfer of learnt theory to practice, in order for IPs to be experts within their fields and not merely adequately competent. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Cytokines as biomarkers of Crimean-Congo hemorrhagic fever.

    PubMed

    Papa, Anna; Tsergouli, Katerina; Çağlayık, Dilek Yağcı; Bino, Silvia; Como, Najada; Uyar, Yavuz; Korukluoglu, Gulay

    2016-01-01

    Crimean-Congo hemorrhagic fever (CCHF) is a potentially severe disease caused by CCHF virus. As in other viral hemorrhagic fevers, it is considered that the course and outcome of the disease depend on the viral load and the balance among the immune response mediators, and that a fatal outcome is the result of a "cytokine storm." The level of 27 cytokines was measured in serum samples taken from 29 patients during the acute phase of the disease. Two cases were fatal. Among survivors, significant differences between severe and non-severe cases were observed in the levels of IP-10, and MCP-1, while the levels of IL-1b, IL-5, IL-6, IL-8, IL-9, IL-10, IL-15, IP-10, MCP-1, TNF-α, and RANTES differed significantly between fatal and non-fatal cases (P < 0.05). RANTES was negatively correlated with the outcome of the disease. A striking similarity with the cytokine patterns seen in Ebola virus disease was observed. A weak Th1 immune response was seen. The viral load was positively correlated with IL-10, IP-10, and MCP-1 levels, and negatively correlated with the ratio IL-12/IL-10. Especially IP-10 and MCP-1 were significantly associated with the viral load, the severity and outcome of the disease, and they could act as biomarkers and, probably, as potential targets for treatment strategies design. © 2015 Wiley Periodicals, Inc.

  11. NHE isoform switching and KChIP2 upregulation in aging porcine atria.

    PubMed

    Kant, Ritu; Hu, Zhaoyang; Malhotra, Jaideep K; Krogh-Madsen, Trine; Christini, David J; Heerdt, Paul M; Abbott, Geoffrey W

    2013-01-01

    Aging increases the risk of cardiac pathologies including atrial fibrillation and can alter myocardial responsiveness to therapeutic agents. Here, seeking molecular correlates of myocardial aging processes, we performed global "whole transcript" analysis of 25,388 genes using 572,667 probes to compare the left atrial (LA) transcriptomes of young adult (9 months old) versus elderly (10 years old) female swine. NHE2 (>9-fold) and KChIP2 (3.8-fold) exhibited the highest aging-related expression increases. Real-time qPCR recapitulated these findings and indicated a 50% decrease in LA NHE1, a twofold increase in right atrial KChIP2, but no significant changes for these transcripts in either ventricle. Notably, even in young adult pigs, NHE2 transcript was detectable and enriched in the atria over the ventricles. NHE1, the recognized cardiac isoform of the sodium hydrogen exchanger, has proven a compelling but clinically disappointing therapeutic target with respect to reperfusion arrhythmias. Our data challenge the dogma that NHE1 is alone in the myocardium and suggest that NHE2 could negatively impact the pharmacological responsiveness of atrial tissue to NHE1-specific inhibitors. KChIP2 is a cytosolic β subunit essential for generation of I to. The increased KChIP2 expression we observed with aging substantially shortened in silico atrial myocyte action potential duration, a predisposing factor in atrial fibrillation. Consistent with this, 4/5 elderly swine sustained pacing-induced AF≥15 s after cessation of stimulation, compared to 0/3 young swine. Our findings uncover potential molecular bases for increased arrhythmogenicity and reduced pharmacologic efficacy in the aging atrium, in a large animal model of human cardiac physiology.

  12. Density functional theory and phytochemical study of Pistagremic acid

    NASA Astrophysics Data System (ADS)

    Ullah, Habib; Rauf, Abdur; Ullah, Zakir; Fazl-i-Sattar; Anwar, Muhammad; Shah, Anwar-ul-Haq Ali; Uddin, Ghias; Ayub, Khurshid

    2014-01-01

    We report here for the first time a comparative theoretical and experimental study of Pistagremic acid (P.A). We have developed a theoretical model for obtaining the electronic and spectroscopic properties of P.A. The simulated data showed nice correlation with the experimental data. The geometric and electronic properties were simulated at B3LYP/6-31 G (d, p) level of density functional theory (DFT). The optimized geometric parameters of P.A were found consistent with those from X-ray crystal structure. Differences of about 0.01 and 0.15 Å in bond length and 0.19-1.30° degree in the angles, respectively; were observed between the experimental and theoretical data. The theoretical vibrational bands of P.A were found to correlate with the experimental IR spectrum after a common scaling factor of 0.963. The experimental and predicted UV-Vis spectra (at B3LYP/6-31+G (d, p)) have 36 nm differences. This difference from experimental results is because of the condensed phase nature of P.A. Electronic properties such as Ionization Potential (I.P), Electron Affinities (E.A), co-efficient of highest occupied molecular orbital (HOMO), co-efficient of lowest unoccupied molecular orbital (LUMO) of P.A were estimated for the first time however, no correlation can be made with experiment. Inter-molecular interaction and its effect on vibrational (IR), electronic and geometric parameters were simulated by using Formic acid as model for hydrogen bonding in P.A.

  13. 77 FR 19284 - Information Collection Being Reviewed by the Federal Communications Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-30

    ... to the SORN. Nature and Extent of Confidentiality: Some assurances of confidentiality are being... captioning of IP-delivered video programming would be economically burdensome: (i) the nature and cost of the... electronically file its petition for exemption, and all subsequent pleadings related to the petition. 47 CFR 79.4...

  14. Problems with the electronic health record.

    PubMed

    de Ruiter, Hans-Peter; Liaschenko, Joan; Angus, Jan

    2016-01-01

    One of the most significant changes in modern healthcare delivery has been the evolution of the paper record to the electronic health record (EHR). In this paper we argue that the primary change has been a shift in the focus of documentation from monitoring individual patient progress to recording data pertinent to Institutional Priorities (IPs). The specific IPs to which we refer include: finance/reimbursement; risk management/legal considerations; quality improvement/safety initiatives; meeting regulatory and accreditation standards; and patient care delivery/evidence based practice. Following a brief history of the transition from the paper record to the EHR, the authors discuss unintended or contested consequences resulting from this change. These changes primarily reflect changes in the organization and amount of clinician work and clinician-patient relationships. The paper is not a research report but was informed by an institutional ethnography the aim of which was to understand how the EHR impacted clinicians and administrators in a large, urban hospital in the United States. The paper was also informed by other sources, including the philosophies of Jacques Ellul, Don Idhe, and Langdon Winner. © 2015 John Wiley & Sons Ltd.

  15. The oxidation/reduction kinetics of the plastoquinone pool controls the appearance of the I-peak in the O-J-I-P chlorophyll fluorescence rise: effects of various electron acceptors.

    PubMed

    Joly, David; Carpentier, Robert

    2007-07-27

    Quantitative analysis of the fluorescence induction (FI) rise was used in this study to elucidate the complex effects of N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) on thylakoids. Reduced TMPD molecules, responsible for the ADRY agent effect, caused an increase in the amplitude of the O-J rise. Also, only oxidized TMPD molecules were shown to have the ability to bind the Q(B) pocket of photosystem II (PSII). On the other hand, the I-P rise was slowed in proportion with the oxidized TMPD concentration, inducing the clear appearance of the I-peak. While this property was previously thought to be unique to TMPD, this study shows that some artificial electron acceptors of PSII, silicomolybdate, 2,5-dichloro-p-benzoquinone, and phenyl-p-benzoquinone, have a similar effect. These results demonstrated a major role of the oxido-reduction kinetics of the PQ-pool in the resolution of J-I and I-P phases in the FI of isolated thylakoids.

  16. Effects of kimchi and smoking on quality characteristics and shelf life of cooked sausages prepared with irradiated pork.

    PubMed

    Kim, Hyun-Wook; Choi, Ji-Hun; Choi, Yun-Sang; Kim, Hack-Youn; Lee, Mi-Ai; Hwang, Ko-Eun; Song, Dong-Heon; Lee, Ju-Woon; Kim, Cheon-Jei

    2014-01-01

    The combined effects of kimchi powder (KP) and smoking (SM) on the quality characteristics and shelf life of cooked sausage prepared with 10 kGy irradiated pork (IP) were studied. The cooked sausages were formulated with single or combined treatment of 0.5% KP and SM (70°C for 30 min). IP+KP+SM treatment showed increased redness, hardness, gumminess, and chewiness, but decreased cooking yield. As for sensory evaluation, treatment with both KP and SM was effective to mask the radiolytic off-flavor. Moreover, the cooked sausage treated with both KP and SM had the highest color, flavor, and overall acceptance (P<0.05), where the differences of flavor patterns were verified by using an electronic nose. During chilled storage for 4 weeks, the combined treatment is effective to retard lipid oxidation, formation of volatile compound, and total microbial number due to the addition of KP. Therefore, usages of KP and SM can provide improved quality characteristics and shelf life of cooked sausage prepared with IP. © 2013.

  17. Detailed study of spontaneous rotation generation in diverted H-mode plasma using the full-f gyrokinetic code XGC1

    NASA Astrophysics Data System (ADS)

    Seo, Janghoon; Chang, C. S.; Ku, S.; Kwon, J. M.; Yoon, E. S.

    2013-10-01

    The Full-f gyrokinetic code XGC1 is used to study the details of toroidal momentum generation in H-mode plasma. Diverted DIII-D geometry is used, with Monte Carlo neutral particles that are recycled at the limiter wall. Nonlinear Coulomb collisions conserve particle, momentum, and energy. Gyrokinetic ions and adiabatic electrons are used in the present simulation to include the effects from ion gyrokinetic turbulence and neoclassical physics, under self-consistent radial electric field generation. Ion orbit loss physics is automatically included. Simulations show a strong co-Ip flow in the H-mode layer at outside midplane, similarly to the experimental observation from DIII-D and ASDEX-U. The co-Ip flow in the edge propagates inward into core. It is found that the strong co-Ip flow generation is mostly from neoclassical physics. On the other hand, the inward momentum transport is from turbulence physics, consistently with the theory of residual stress from symmetry breaking. Therefore, interaction between the neoclassical and turbulence physics is a key factor in the spontaneous momentum generation.

  18. Hydrocarbon potential of Upper Devonian black shale, eastern Kentucky

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

    Johnston, I.M.; Frankie, W.T.; Moody, J.R.

    The gas-producing Upper Devonian black shales of eastern Kentucky represent cycles of organic units alternating with less-organic units that were dominated by an influx of clastics from a northeastern source. This pattern of sedimentation is typical throughout the southern Appalachian basin in areas basinal to, yet still influenced by, the Catskill delta to the northwest. These black shales, which thin westward onto the Cincinnati arch, dip eastward into the Appalachian basin. To evaluate the future gas potential of Devonian shale, a data base has been compiled, consisting of specific geologic and engineering information from 5920 Devonian shale wells in Letcher,more » Knott, Floyd, Martin, and Pike Counties, Kentucky. The first successful gas completion in eastern Kentucky was drilled in Martin County in 1901. Comparison of initial open-flow potential (IP) and long-term production data for these wells demonstrates that higher IP values generally indicate wells of higher production potential. Areas of higher IP are aligned linearly, and these lineaments are interpreted to be related to fracture systems within the Devonian shale. These fractures may be basement influenced. Temperature log analyses indicate that the greatest number of natural gas shows occur in the lower Huron Member of the Ohio Shale. Using both the temperature log to indicate gas shows and the gamma-ray log to determine the producing unit is a workable method for selecting the interval for treatment.« less

  19. Application of modern autoradiography to nuclear forensic analysis

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

    Parsons-Davis, Tashi; Knight, Kim; Fitzgerald, Marc

    Modern autoradiography techniques based on phosphorimaging technology using image plates (IPs) and digital scanning can identify heterogeneities in activity distributions and reveal material properties, serving to inform subsequent analyses. Here, we have adopted these advantages for applications in nuclear forensics, the technical analysis of radioactive or nuclear materials found outside of legal control to provide data related to provenance, production history, and trafficking route for the materials. IP autoradiography is a relatively simple, non-destructive method for sample characterization that records an image reflecting the relative intensity of alpha and beta emissions from a two-dimensional surface. Such data are complementary tomore » information gathered from radiochemical characterization via bulk counting techniques, and can guide the application of other spatially resolved techniques such as scanning electron microscopy (SEM) and secondary ion mass spectrometry (SIMS). IP autoradiography can image large 2-dimenstional areas (up to 20 × 40 cm), with relatively low detection limits for actinides and other radioactive nuclides, and sensitivity to a wide dynamic range (10 5) of activity density in a single image. Distributions of radioactivity in nuclear materials can be generated with a spatial resolution of approximately 50 μm using IP autoradiography and digital scanning. While the finest grain silver halide films still provide the best possible resolution (down to ~10 μm), IP autoradiography has distinct practical advantages such as shorter exposure times, no chemical post-processing, reusability, rapid plate scanning, and automated image digitization. Sample preparation requirements are minimal, and the analytical method does not consume or alter the sample. These advantages make IP autoradiography ideal for routine screening of nuclear materials, and for the identification of areas of interest for subsequent micro-characterization methods. Here in this article we present a summary of our setup, as modified for nuclear forensic sample analysis and related research, and provide examples of data from select samples from the nuclear fuel cycle and historical nuclear test debris.« less

  20. Application of modern autoradiography to nuclear forensic analysis

    DOE PAGES

    Parsons-Davis, Tashi; Knight, Kim; Fitzgerald, Marc; ...

    2018-05-20

    Modern autoradiography techniques based on phosphorimaging technology using image plates (IPs) and digital scanning can identify heterogeneities in activity distributions and reveal material properties, serving to inform subsequent analyses. Here, we have adopted these advantages for applications in nuclear forensics, the technical analysis of radioactive or nuclear materials found outside of legal control to provide data related to provenance, production history, and trafficking route for the materials. IP autoradiography is a relatively simple, non-destructive method for sample characterization that records an image reflecting the relative intensity of alpha and beta emissions from a two-dimensional surface. Such data are complementary tomore » information gathered from radiochemical characterization via bulk counting techniques, and can guide the application of other spatially resolved techniques such as scanning electron microscopy (SEM) and secondary ion mass spectrometry (SIMS). IP autoradiography can image large 2-dimenstional areas (up to 20 × 40 cm), with relatively low detection limits for actinides and other radioactive nuclides, and sensitivity to a wide dynamic range (10 5) of activity density in a single image. Distributions of radioactivity in nuclear materials can be generated with a spatial resolution of approximately 50 μm using IP autoradiography and digital scanning. While the finest grain silver halide films still provide the best possible resolution (down to ~10 μm), IP autoradiography has distinct practical advantages such as shorter exposure times, no chemical post-processing, reusability, rapid plate scanning, and automated image digitization. Sample preparation requirements are minimal, and the analytical method does not consume or alter the sample. These advantages make IP autoradiography ideal for routine screening of nuclear materials, and for the identification of areas of interest for subsequent micro-characterization methods. Here in this article we present a summary of our setup, as modified for nuclear forensic sample analysis and related research, and provide examples of data from select samples from the nuclear fuel cycle and historical nuclear test debris.« less

  1. Application of modern autoradiography to nuclear forensic analysis.

    PubMed

    Parsons-Davis, Tashi; Knight, Kim; Fitzgerald, Marc; Stone, Gary; Caldeira, Lee; Ramon, Christina; Kristo, Michael

    2018-05-01

    Modern autoradiography techniques based on phosphorimaging technology using image plates (IPs) and digital scanning can identify heterogeneities in activity distributions and reveal material properties, serving to inform subsequent analyses. Here, we have adopted these advantages for applications in nuclear forensics, the technical analysis of radioactive or nuclear materials found outside of legal control to provide data related to provenance, production history, and trafficking route for the materials. IP autoradiography is a relatively simple, non-destructive method for sample characterization that records an image reflecting the relative intensity of alpha and beta emissions from a two-dimensional surface. Such data are complementary to information gathered from radiochemical characterization via bulk counting techniques, and can guide the application of other spatially resolved techniques such as scanning electron microscopy (SEM) and secondary ion mass spectrometry (SIMS). IP autoradiography can image large 2-dimenstional areas (up to 20×40cm), with relatively low detection limits for actinides and other radioactive nuclides, and sensitivity to a wide dynamic range (10 5 ) of activity density in a single image. Distributions of radioactivity in nuclear materials can be generated with a spatial resolution of approximately 50μm using IP autoradiography and digital scanning. While the finest grain silver halide films still provide the best possible resolution (down to ∼10μm), IP autoradiography has distinct practical advantages such as shorter exposure times, no chemical post-processing, reusability, rapid plate scanning, and automated image digitization. Sample preparation requirements are minimal, and the analytical method does not consume or alter the sample. These advantages make IP autoradiography ideal for routine screening of nuclear materials, and for the identification of areas of interest for subsequent micro-characterization methods. In this paper we present a summary of our setup, as modified for nuclear forensic sample analysis and related research, and provide examples of data from select samples from the nuclear fuel cycle and historical nuclear test debris. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Modification of crystal habit of ibuprofen using the phase partition technique: effect of aerosil and tween 80 in binding solvent.

    PubMed

    Umprayn, K; Luengtummuen, A; Kitiyadisai, C; Pornpiputsakul, T

    2001-11-01

    A ternary diagram, representing the solubility of binding solvent (chloroform) in a mixture of ethanol and water, was constructed. For this study, the solvent mixture that gave the best ibuprofen pellets (IPs) was composed of chloroform.ethanol:water at a ratio of 1.5%:8%:90.5%. The suitable agitator speed, temperature, and mixing time were found to be 1,500 rpm, 25 degrees C +/- 2 degrees C, and 20 min, respectively. In addition, suitable stirring time when the phase partition process of IPs began was 15 min. IPs obtained from these conditions were small and round, approximately 1 mm; surface determination by scanning electron microscopy (SEM) indicated that the IPs were composed of drug microcrystals rearranged on the surface. For the dissolution, IPs showed lower drug release when compared with pure ibuprofen crystal (IC) (f2 analysis). An attempt to modify the dissolution property of IP by incorporating various concentrations of Aerosil and Tween 80 in the binding solvent was made. Microscopic appearance showed that both Aerosil and Tween 80 gave less spherical pellets when compared with the use of binding solvent alone. For both the Aerosil and Tween 80 employed, the results indicated a change in rearrangement of drug microcrystals and a change in crystal habit. However, Tween 80 gave more change of the crystallographic direction of drug microcrystals than Aerosil. In term of dissolution, the results showed that employing Tween 80 at 1.2% gave the highest drug release compared to the use of Aerosil and IC alone (f2 analysis). These pellets had a good flow property, as indicated by Carr's compressibility, flow rate, and angle of repose, and they can be compressed into a tablet, encapsulated by suitable polymer, or pulverized to obtain micronized crystals. In the case of compression into tablets, the dissolution profiles of these tablets compared with those of commercial product meet the USP 24 requirement (Q > or = 80% at 60 min).

  3. Barriers and strategies for improving communication between inpatient and outpatient mental health clinicians.

    PubMed

    Stockdale, Susan E; Sherin, Jonathan E; Chan, Jeffrey A; Hermann, Richard C

    2011-11-01

    To explore hospital leaders' perceptions of organisational factors as barriers and/or facilitators in improving inpatient-outpatient (IP-OP) communication. Semistructured in-person interviews. Constant comparative method of qualitative data. Inpatient psychiatry units in 33 general medical/surgical and specialty psychiatric hospitals in California and Massachusetts (USA). Psychiatry chair/chief, service director or medical director. Importance to leadership, resources, organisational structure and culture. A majority of hospital leaders rated the IP-OP communication objective as highly or moderately important. Hospitals with good IP-OP communication had structures in place to support communication or had changed/implemented new procedures to enhance communication, and anticipated clinicians would 'buy in' to the goal of improved communication. Hospitals reporting no improvement efforts were less likely to have structures supporting IP-OP communication, anticipated resistance among clinicians and reported a need for technological resources such as electronic health records, integrated IT and secure online communication. Most leaders reported a need for additional staff time and information, knowledge or data. For many hospitals, successfully improving communication will require overcoming organisational barriers such as cultures not conducive to change and lack of resources and infrastructure. Creating a culture that values communication at discharge may help improve outcomes following hospitalisation, but changes in healthcare delivery in the past few decades may necessitate new strategies or changes at the systems level to address barriers to effective communication.

  4. AFM and SEM study of the effects of etching on IPS-Empress 2 TM dental ceramic

    NASA Astrophysics Data System (ADS)

    Luo, X.-P.; Silikas, N.; Allaf, M.; Wilson, N. H. F.; Watts, D. C.

    2001-10-01

    The aim of this study was to investigate the effects of increasing etching time on the surface of the new dental material, IPS-Empress 2 TM glass ceramic. Twenty one IPS-Empress 2 TM glass ceramic samples were made from IPS-Empress 2 TM ingots through lost-wax, hot-pressed ceramic fabrication technology. All samples were highly polished and cleaned ultrasonically for 5 min in acetone before and after etching with 9.6% hydrofluoric acid gel. The etching times were 0, 10, 20, 30, 60, 90 and 120 s respectively. Microstructure was analysed by scanning electron microscopy (SEM) and atomic force microscopy (AFM) was used to evaluate the surface roughness and topography. Observations with SEM showed that etching with hydrofluoric acid resulted in preferential dissolution of glass matrix, and that partially supported crystals within the glass matrix were lost with increasing etching time. AFM measurements indicated that etching increased the surface roughness of the glass-ceramic. A simple least-squares linear regression was used to establish a relationship between surface roughness parameters ( Ra, RMS), and etching time, for which r2>0.94. This study demonstrates the benefits of combining two microscopic methods for a better understanding of the surface. SEM showed the mode of action of hydrofluoric acid on the ceramic and AFM provided valuable data regarding the extent of surface degradation relative to etching time.

  5. The correlations of the electronic structure and film growth of 2,7-diocty[1]benzothieno[3,2-b]benzothiophene (C8-BTBT) on SiO2.

    PubMed

    Lyu, Lu; Niu, Dongmei; Xie, Haipeng; Zhao, Yuan; Cao, Ningtong; Zhang, Hong; Zhang, Yuhe; Liu, Peng; Gao, Yongli

    2017-01-04

    Combining ultraviolet photoemission spectroscopy (UPS), X-ray photoemission spectroscopy (XPS), atomic force microscopy (AFM) and small angle X-ray diffraction (SAXD) measurements, we perform a systematic investigation on the correlations of the electronic structure, film growth and molecular orientation of 2,7-diocty[1]benzothieno[3,2-b]benzothiophene (C8-BTBT) on silicon oxide (SiO 2 ). AFM analysis reveals a phase transition of disorderedly oriented molecules in clusters in thinner films to highly ordered standing-up molecules in islands in thicker films. SAXD peaks consistently support the standing-up configuration in islands. The increasing ordering of the molecular orientation with film thickness contributes to the changing of the shape and lowering of the leading edge of the highest occupied molecular orbital (HOMO). The end methyl of the highly ordered standing molecules forms an outward pointing dipole layer which makes the work function (WF) decrease with increasing thickness. The downward shift of the HOMO and a decrease of WF result in unconventional downward band bending and decreased ionization potential (IP). The correlations of the orientation ordering of molecules, film growth and interface electronic structures provide a useful design strategy to improve the performance of C8-BTBT thin film based field effect transistors.

  6. The Science and Ethics of Induced Pluripotency: What Will Become of Embryonic Stem Cells?

    PubMed Central

    Zacharias, David G.; Nelson, Timothy J.; Mueller, Paul S.; Hook, C. Christopher

    2011-01-01

    For over a decade, the field of stem cell research has advanced tremendously and gained new attention in light of novel insights and emerging developments for regenerative medicine. Invariably, multiple considerations come into play, and clinicians and researchers must weigh the benefits of certain stem cell platforms against the costs they incur. Notably, human embryonic stem (hES) cell research has been a source of continued debate, leading to differing policies and regulations worldwide. This article briefly reviews current stem cell platforms, looking specifically at the two existing pluripotent lines available for potential therapeutic applications: hES cells and induced pluripotent stem (iPS) cells. We submit iPS technology as a viable and possibly superior alternative for future medical and research endeavors as it obviates many ethical and resource-related concerns posed by hES cells while prospectively matching their potential for scientific use. However, while the clinical realities of iPS cells appear promising, we must recognize the current limitations of this technology, avoid hype, and articulate ethically acceptable medical and scientific goals. PMID:21719620

  7. 49 CFR 173.427 - Transport requirements for low specific activity (LSA) Class 7 (radioactive) materials and...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... package (IP-1, IP-2 or IP-3; § 173.411), subject to the limitations of Table 6; (2) In a DOT Specification... use shipment 1. LSA-I: Solid IP-1 IP-1 Liquid IP-1 IP-2 2. LSA-II: Solid IP-2 IP-2 Liquid and gas IP-2 IP-3 3. LSA-III IP-2 IP-3 4. SCO-I IP-1 IP-1 5. SCO-II IP-2 IP-2 [69 FR 3676, Jan. 26, 2004; 69 FR...

  8. 49 CFR 173.427 - Transport requirements for low specific activity (LSA) Class 7 (radioactive) materials and...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... package (IP-1, IP-2 or IP-3; § 173.411), subject to the limitations of Table 6; (2) In a DOT Specification... use shipment 1. LSA-I: Solid IP-1 IP-1 Liquid IP-1 IP-2 2. LSA-II: Solid IP-2 IP-2 Liquid and gas IP-2 IP-3 3. LSA-III IP-2 IP-3 4. SCO-I IP-1 IP-1 5. SCO-II IP-2 IP-2 [69 FR 3676, Jan. 26, 2004; 69 FR...

  9. Radiation Belt response to the July 2017 Coronal Mass Ejection and the Interplanetary Shock

    NASA Astrophysics Data System (ADS)

    Kanekal, S. G.; Baker, D. N.; Jones, A. D.; Schiller, Q. A.; Sibeck, D. G.; Elkington, S. R.; Hoxie, V. C.; Jaynes, A. N.; Li, X.; Zhao, H.; Blake, J. B.; Claudepierre, S. G.; Fennell, J. F.; Turner, D. L.

    2017-12-01

    A coronal mass ejection that erupted on July 14, 2017 impacted the radiation belts on July 16, 2017 and resulted in a moderate geomagnetic storm. The immediate response of the energetic electrons to the interplanetary shock ahead of the CME, showed hock-induced energization as well as drift echoes in the L range of 4 to 5 . Increased electron fluxes were seen to energies up to 5 MeV as observed by the Relativistic Electron and Proton Telescope and the Magnetic Electron and Ion Sensors on board NASA's Van Allen Probes. We report on these observations, both immediately after the IP shock passage and the more gradual response to the CME. we discuss the observation in the context of electron dynamics in the terrestrial radiation belts.

  10. Application of SQL database to the control system of MOIRCS

    NASA Astrophysics Data System (ADS)

    Yoshikawa, Tomohiro; Omata, Koji; Konishi, Masahiro; Ichikawa, Takashi; Suzuki, Ryuji; Tokoku, Chihiro; Uchimoto, Yuka Katsuno; Nishimura, Tetsuo

    2006-06-01

    MOIRCS (Multi-Object Infrared Camera and Spectrograph) is a new instrument for the Subaru telescope. In order to perform observations of near-infrared imaging and spectroscopy with cold slit mask, MOIRCS contains many device components, which are distributed on an Ethernet LAN. Two PCs wired to the focal plane array electronics operate two HAWAII2 detectors, respectively, and other two PCs are used for integrated control and quick data reduction, respectively. Though most of the devices (e.g., filter and grism turrets, slit exchange mechanism for spectroscopy) are controlled via RS232C interface, they are accessible from TCP/IP connection using TCP/IP to RS232C converters. Moreover, other devices are also connected to the Ethernet LAN. This network distributed structure provides flexibility of hardware configuration. We have constructed an integrated control system for such network distributed hardwares, named T-LECS (Tohoku University - Layered Electronic Control System). T-LECS has also network distributed software design, applying TCP/IP socket communication to interprocess communication. In order to help the communication between the device interfaces and the user interfaces, we defined three layers in T-LECS; an external layer for user interface applications, an internal layer for device interface applications, and a communication layer, which connects two layers above. In the communication layer, we store the data of the system to an SQL database server; they are status data, FITS header data, and also meta data such as device configuration data and FITS configuration data. We present our software system design and the database schema to manage observations of MOIRCS with Subaru.

  11. The expression of asparaginyl endopeptidase promotes growth potential in epithelial ovarian cancer.

    PubMed

    Zhu, Qinyi; Tang, Meiling; Wang, Xipeng

    2017-04-03

    Epithelial ovarian cancer (EOC) is the most common and lethal cancer-related death among females in the world. Asparaginyl endopeptidase (AEP) is a member of C13 family peptidases and expressed in the extracellular matrix and tumor cells. The aim of this article is to explore the function of asparaginyl endopeptidase in epithelial ovarian cancer. The expression of AEP was examined in 20 EOC samples, 3 EOC metastasis samples, 6 fallopian tube metastasis samples, 4 peritoneum metastasis samples and 20 benign ovarian tumor samples by immunohistochemistry. The expression of AEP was also evaluated in serum and ascites of EOC patients by elisa. And we used a lentiviral vector to overexpress AEP in human epithelial ovarian cancer cell lines SKOV3ip and detected the function of AEP-SKOV3ip cells both in vitro and in vivo. The growth of AEP-SKOV3ip cells was observed by MTT, migration and tube formation assays in vitro. Additionally, the subcutaneous mice model was used to identify the tumor growth and metastasis in vivo. Mice tumors were stained for CD31 to determine the microvessel density (MVD). We demonstrated that AEP was highly expressed in the EOC patient tissues and ascites. The AEP transfected SKOV3ip cells could both promote tumor growth in vitro and in vivo. The MVD in AEP-SKOV3ip group was higher than that in NC-SKOV3ip group. Therefore, our results demonstrated that AEP could induce EOC growth and progressionboth in vitro and in vivo.

  12. Systems Modeling of Ca2+ Homeostasis and Mobilization in Platelets Mediated by IP3 and Store-Operated Ca2+ Entry

    PubMed Central

    Dolan, Andrew T.; Diamond, Scott L.

    2014-01-01

    Resting platelets maintain a stable level of low cytoplasmic calcium ([Ca2+]cyt) and high dense tubular system calcium ([Ca2+]dts). During thrombosis, activators cause a transient rise in inositol trisphosphate (IP3) to trigger calcium mobilization from stores and elevation of [Ca2+]cyt. Another major source of [Ca2+]cyt elevation is store-operated calcium entry (SOCE) through plasmalemmal calcium channels that open in response to store depletion as [Ca2+]dts drops. A 34-species systems model employed kinetics describing IP3-receptor, DTS-plasmalemma puncta formation, SOCE via assembly of STIM1 and Orai1, and the plasmalemma and sarco/endoplasmic reticulum Ca2+-ATPases. Four constraints were imposed: calcium homeostasis before activation; stable in zero extracellular calcium; IP3-activatable; and functional SOCE. Using a Monte Carlo method to sample three unknown parameters and nine initial concentrations in a 12-dimensional space near measured or expected values, we found that model configurations that were responsive to stimuli and demonstrated significant SOCE required high inner membrane electric potential (>−70 mV) and low resting IP3 concentrations. The absence of puncta in resting cells was required to prevent spontaneous store depletion in calcium-free media. Ten-fold increases in IP3 caused saturated calcium mobilization. This systems model represents a critical step in being able to predict platelets’ phenotypes during hemostasis or thrombosis. PMID:24806937

  13. [Exploiture and application of an internet-based Computation Platform for Integrative Pharmacology of Traditional Chinese Medicine].

    PubMed

    Xu, Hai-Yu; Liu, Zhen-Ming; Fu, Yan; Zhang, Yan-Qiong; Yu, Jian-Jun; Guo, Fei-Fei; Tang, Shi-Huan; Lv, Chuan-Yu; Su, Jin; Cui, Ru-Yi; Yang, Hong-Jun

    2017-09-01

    Recently, integrative pharmacology(IP) has become a pivotal paradigm for the modernization of traditional Chinese medicines(TCM) and combinatorial drugs discovery, which is an interdisciplinary science for establishing the in vitro and in vivo correlation between absorption, distribution, metabolism, and excretion/pharmacokinetic(ADME/PK) profiles of TCM and the molecular networks of disease by the integration of the knowledge of multi-disciplinary and multi-stages. In the present study, an internet-based Computation Platform for IP of TCM(TCM-IP, www.tcmip.cn) is established to promote the development of the emerging discipline. Among them, a big data of TCM is an important resource for TCM-IP including Chinese Medicine Formula Database, Chinese Medical Herbs Database, Chemical Database of Chinese Medicine, Target Database for Disease and Symptoms, et al. Meanwhile, some data mining and bioinformatics approaches are critical technology for TCM-IP including the identification of the TCM constituents, ADME prediction, target prediction for the TCM constituents, network construction and analysis, et al. Furthermore, network beautification and individuation design are employed to meet the consumer's requirement. We firmly believe that TCM-IP is a very useful tool for the identification of active constituents of TCM and their involving potential molecular mechanism for therapeutics, which would wildly applied in quality evaluation, clinical repositioning, scientific discovery based on original thinking, prescription compatibility and new drug of TCM, et al. Copyright© by the Chinese Pharmaceutical Association.

  14. p53 isoform Δ133p53 promotes efficiency of induced pluripotent stem cells and ensures genomic integrity during reprogramming.

    PubMed

    Gong, Lu; Pan, Xiao; Chen, Haide; Rao, Lingjun; Zeng, Yelin; Hang, Honghui; Peng, Jinrong; Xiao, Lei; Chen, Jun

    2016-11-22

    Human induced pluripotent stem (iPS) cells have great potential in regenerative medicine, but this depends on the integrity of their genomes. iPS cells have been found to contain a large number of de novo genetic alterations due to DNA damage response during reprogramming. Thus, to maintain the genetic stability of iPS cells is an important goal in iPS cell technology. DNA damage response can trigger tumor suppressor p53 activation, which ensures genome integrity of reprogramming cells by inducing apoptosis and senescence. p53 isoform Δ133p53 is a p53 target gene and functions to not only antagonize p53 mediated apoptosis, but also promote DNA double-strand break (DSB) repair. Here we report that Δ133p53 is induced in reprogramming. Knockdown of Δ133p53 results 2-fold decrease in reprogramming efficiency, 4-fold increase in chromosomal aberrations, whereas overexpression of Δ133p53 with 4 Yamanaka factors showes 4-fold increase in reprogamming efficiency and 2-fold decrease in chromosomal aberrations, compared to those in iPS cells induced only with 4 Yamanaka factors. Overexpression of Δ133p53 can inhibit cell apoptosis and promote DNA DSB repair foci formation during reprogramming. Our finding demonstrates that the overexpression of Δ133p53 not only enhances reprogramming efficiency, but also results better genetic quality in iPS cells.

  15. Modeling Alzheimer’s disease with human induced pluripotent stem (iPS) cells

    PubMed Central

    Mungenast, Alison E.; Siegert, Sandra; Tsai, Li-Huei

    2018-01-01

    In the last decade, induced pluripotent stem (iPS) cells have revolutionized the utility of human in vitro models of neurological disease. The iPS-derived and differentiated cells allow researchers to study the impact of a distinct cell type in health and disease as well as performing therapeutic drug screens on a human genetic background. In particular, clinical trials for Alzheimer’s disease (AD) have been often failing. Two of the potential reasons are first, the species gap involved in proceeding from initial discoveries in rodent models to human studies, and second, an unsatisfying patient stratification, meaning subgrouping patients based on the disease severity due to the lack of phenotypic and genetic markers. iPS cells overcome this obstacles and will improve our understanding of disease subtypes in AD. They allow researchers conducting in depth characterization of neural cells from both familial and sporadic AD patients as well as preclinical screens on human cells. In this review, we briefly outline the status quo of iPS cell research in neurological diseases along with the general advantages and pitfalls of these models. We summarize how genome-editing techniques such as CRISPR/Cas will allow researchers to reduce the problem of genomic variability inherent to human studies, followed by recent iPS cell studies relevant to AD. We then focus on current techniques for the differentiation of iPS cells into neural cell types that are relevant to AD research. Finally, we discuss how the generation of three-dimensional cell culture systems will be important for understanding AD phenotypes in a complex cellular milieu, and how both two- and three-dimensional iPS cell models can provide platforms for drug discovery and translational studies into the treatment of AD. PMID:26657644

  16. Modeling Alzheimer's disease with human induced pluripotent stem (iPS) cells.

    PubMed

    Mungenast, Alison E; Siegert, Sandra; Tsai, Li-Huei

    2016-06-01

    In the last decade, induced pluripotent stem (iPS) cells have revolutionized the utility of human in vitro models of neurological disease. The iPS-derived and differentiated cells allow researchers to study the impact of a distinct cell type in health and disease as well as performing therapeutic drug screens on a human genetic background. In particular, clinical trials for Alzheimer's disease (AD) have been failing. Two of the potential reasons are first, the species gap involved in proceeding from initial discoveries in rodent models to human studies, and second, an unsatisfying patient stratification, meaning subgrouping patients based on the disease severity due to the lack of phenotypic and genetic markers. iPS cells overcome this obstacles and will improve our understanding of disease subtypes in AD. They allow researchers conducting in depth characterization of neural cells from both familial and sporadic AD patients as well as preclinical screens on human cells. In this review, we briefly outline the status quo of iPS cell research in neurological diseases along with the general advantages and pitfalls of these models. We summarize how genome-editing techniques such as CRISPR/Cas9 will allow researchers to reduce the problem of genomic variability inherent to human studies, followed by recent iPS cell studies relevant to AD. We then focus on current techniques for the differentiation of iPS cells into neural cell types that are relevant to AD research. Finally, we discuss how the generation of three-dimensional cell culture systems will be important for understanding AD phenotypes in a complex cellular milieu, and how both two- and three-dimensional iPS cell models can provide platforms for drug discovery and translational studies into the treatment of AD. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. In vivo programming of tumor antigen-specific T lymphocytes from pluripotent stem cells to promote cancer immunosurveillance.

    PubMed

    Lei, Fengyang; Zhao, Baohua; Haque, Rizwanul; Xiong, Xiaofang; Budgeon, Lynn; Christensen, Neil D; Wu, Yuzhang; Song, Jianxun

    2011-07-15

    Adoptive T-cell immunotherapy has garnered wide attention, but its effective use is limited by the need of multiple ex vivo manipulations and infusions that are complex and expensive. In this study, we show how highly reactive antigen (Ag)-specific CTLs can be generated from induced pluripotent stem (iPS) cells to provide an unlimited source of functional CTLs for adoptive immunotherapy. iPS cell-derived T cells can offer the advantages of avoiding possible immune rejection and circumventing ethical and practical issues associated with other stem cell types. iPS cells can be differentiated into progenitor T cells in vitro by stimulation with the Notch ligand Delta-like 1 (DL1) overexpressed on bone marrow stromal cells, with complete maturation occurring upon adoptive transfer into Rag1-deficient mice. Here, we report that these iPS cells can be differentiated in vivo into functional CTLs after overexpression of MHC I-restricted Ag-specific T-cell receptors (TCR). In this study, we generated murine iPS cells genetically modified with ovalbumin (OVA)-specific and MHC-I restricted TCR (OT-I) by retrovirus-mediated transduction. After their adoptive transfer into recipient mice, the majority of OT-I/iPS cells underwent differentiation into CD8+ CTLs. TCR-transduced iPS cells developed in vivo responded in vitro to peptide stimulation by secreting interleukin 2 and IFN-γ. Most importantly, adoptive transfer of TCR-transduced iPS cells triggered infiltration of OVA-reactive CTLs into tumor tissues and protected animals from tumor challenge. Taken together, our findings offer proof of concept for a potentially more efficient approach to generate Ag-specific T lymphocytes for adoptive immunotherapy. ©2011 AACR.

  18. Epigenetic rejuvenation.

    PubMed

    Manukyan, Maria; Singh, Prim B

    2012-05-01

    Induced pluripotent stem (iPS) cells have provided a rational means of obtaining histo-compatible tissues for 'patient-specific' regenerative therapies (Hanna et al. 2010; Yamanaka & Blau 2010). Despite the obvious potential of iPS cell-based therapies, there are certain problems that must be overcome before these therapies can become safe and routine (Ohi et al. 2011; Pera 2011). As an alternative, we have recently explored the possibility of using 'epigenetic rejuvenation', where the specialized functions of an old cell are rejuvenated in the absence of any change in its differentiated state (Singh & Zacouto 2010). The mechanism(s) that underpin 'epigenetic rejuvenation' are unknown and here we discuss model systems, using key epigenetic modifiers, which might shed light on the processes involved. Epigenetic rejuvenation has advantages over iPS cell techniques that are currently being pursued. First, the genetic and epigenetic abnormalities that arise through the cycle of dedifferentiation of somatic cells to iPS cells followed by redifferentiation of iPS cells into the desired cell type are avoided (Gore et al. 2011; Hussein et al. 2011; Pera 2011): epigenetic rejuvenation does not require passage through the de-/redifferentiation cycle. Second, because the aim of epigenetic rejuvenation is to ensure that the differentiated cell type retains its specialized function it makes redundant the question of transcriptional memory that is inimical to iPS cell-based therapies (Ohi et al. 2011). Third, to produce unrelated cell types using the iPS technology takes a long time, around three weeks, whereas epigenetic rejuvenation of old cells will take only a matter of days. Epigenetic rejuvenation provides the most safe, rapid and cheap route to successful regenerative medicine. © 2012 The Authors. Journal compilation © 2012 by the Molecular Biology Society of Japan/Blackwell Publishing Ltd.

  19. Imaging Coronal Mass Ejections and Large-Scale Solar Wind Structure Using IPS and Thomson-Scattered Sunlight (Invited)

    NASA Astrophysics Data System (ADS)

    Clover, J. M.; Jackson, B. V.; Buffington, A.; Hick, P. P.; Bisi, M. M.; Tokumaru, M.; Fujiki, K.

    2010-12-01

    The Solar Mass Ejection Imager (SMEI) observes Thomson-scattered white light from heliospheric electrons across almost all of the sky nearly all of the time since early 2003. Interplanetary scintillation (IPS) observations of velocity and g-level provide similar structure information but with a less-complete sky-and-time coverage. The Solar TErrestrial RElations Observatory (STEREO) twin spacecraft outer Heliospheric Imagers (HI-2) currently image the heliosphere in Thomson-scattered light near the ecliptic plane far from Earth. The Solar-Terrestrial Environment Laboratory (STELab) IPS observations provide IPS velocity and g-level values, which in conjunction with our tomographic reconstruction program, yield velocities and densities of the inner heliosphere in three dimensions. The same tomographic program substitutes SMEI Thomson-scattering brightness information for the g-level values to derive heliospheric densities from these data alone. We look at the global structure of the heliosphere concentrating mainly on three events from 2007 through the rise phase of Solar Cycle 24. The first event, observed in both the IPS and SMEI defines the three-dimensional velocity and density structure around the time of the shock observed at Earth on 02:02 UT 17 December 2007. The second event, seen only by SMEI, is that of the 23-26 April 2008 coronal mass ejection (CME) and its interplanetary counterpart. The third event is the CME (and its interplanetary counterpart) that took place 17 January 2010 and arrived at STEREO-B about four days later. For each event, we isolate the particular portion of the heliosphere attributed to the transient density structure using our tomographic technique, and then estimate its extent.

  20. An innovative nanophotonic information processing concept implementing cogent micro/nanosensors for space robotics

    NASA Astrophysics Data System (ADS)

    Santoli, Salvatore

    2013-02-01

    Cogent sensors, defined as sensors that are capable of performing the transformation of raw data into information, are shown to be of the essence for realization of the long sought-after autonomous robots for space applications. A strongly miniaturized integration of sensing and information processing systems is needed for cogent sensors designed for autonomous sensing—information processing (IP)—actuating behavior. It is shown that the recently developed field of quantum holography (QH), stemming from geometric quantization of any holographic processes through the Heisenberg Group (G) and deeply different, as stressed in detail, from other meanings of "quantum holography" in the literature, supplies the nanophotonic tools for designing and assembling an associative memory (AM) as the brain implementing such strong cogency. An AM is designed through a free-space interconnected large planar multilayer architecture of quantum well-based two-port neurons implementing a shift register on the manifold of G, and whose input consists of photonic holograms from high frequency pulsed microlasers in the infrared band of em or em-transduced outside signals. The optoelectronics as relative, integrated into a hybrid chip involving photonic detectors, microlasers and electronic components for the clock control system, would allow cycle times as short as 30 ns with the large spatial bandwidth available in photonics. IP through QH concerns the encoding and decoding of holographic interference patterns, not of mere binary digital logical (syntactic) information. Accordingly, QH defines on the G's manifold an IP paradigm where information as experimental knowledge is processed; i.e., IP concerns both syntax and semantics. It is shown that such QH-neural brain would cogently deal with spurious signals as random noise that would be caused to die out on the way to the intended target through parallel massive and real-time IP.

  1. Combining genomic and proteomic approaches for epigenetics research

    PubMed Central

    Han, Yumiao; Garcia, Benjamin A

    2014-01-01

    Epigenetics is the study of changes in gene expression or cellular phenotype that do not change the DNA sequence. In this review, current methods, both genomic and proteomic, associated with epigenetics research are discussed. Among them, chromatin immunoprecipitation (ChIP) followed by sequencing and other ChIP-based techniques are powerful techniques for genome-wide profiling of DNA-binding proteins, histone post-translational modifications or nucleosome positions. However, mass spectrometry-based proteomics is increasingly being used in functional biological studies and has proved to be an indispensable tool to characterize histone modifications, as well as DNA–protein and protein–protein interactions. With the development of genomic and proteomic approaches, combination of ChIP and mass spectrometry has the potential to expand our knowledge of epigenetics research to a higher level. PMID:23895656

  2. Generation of transgene-free induced pluripotent stem cells with non-viral methods.

    PubMed

    Wang, Tao; Zhao, Hua-shan; Zhang, Qiu-ling; Xu, Chang-lin; Liu, Chang-bai

    2013-03-01

    Induced pluripotent stem (iPS) cells were originally generated from mouse fibroblasts by enforced expression of Yamanaka factors (Oct3/4, Sox2, Klf4, and c-Myc). The technique was quickly reproduced with human fibroblasts or mesenchymal stem cells. Although having been showed therapeutic potential in animal models of sickle cell anemia and Parkinson's disease, iPS cells generated by viral methods do not suit all the clinical applications. Various non-viral methods have appeared in recent years for application of iPS cells in cell transplantation therapy. These methods mainly include DNA vector-based approaches, transfection of mRNA, and transduction of reprogramming proteins. This review summarized these non-viral methods and compare the advantages, disadvantages, efficiency, and safety of these methods.

  3. Epigenome analysis of pluripotent stem cells

    PubMed Central

    Ricupero, Christopher L.; Swerdel, Mavis R.; Hart, Ronald P.

    2015-01-01

    Summary Mis-regulation of gene expression due to epigenetic abnormalities has been linked with complex genetic disorders, psychiatric illness and cancer. In addition, the dynamic epigenetic changes that occur in pluripotent stem cells are believed to impact regulatory networks essential for proper lineage development. Chromatin immunoprecipitation (ChIP) is a technique used to isolate and enrich chromatin fragments using antibodies against specific chromatin modifications, such as DNA binding proteins or covalent histone modifications. Until recently, many ChIP protocols required millions of cells for each immunoprecipitation. This severely limited analysis of rare cell populations or post-mitotic, differentiated cell lines. Here, we describe a low cell number ChIP protocol with next generation sequencing and analysis, that has the potential to uncover novel epigenetic regulatory pathways that were previously difficult or impossible to obtain. PMID:23546758

  4. Immunopotentiator from Pantoea agglomerans 1 (IP-PA1) Promotes Murine Hair Growth and Human Dermal Papilla Cell Gene Expression.

    PubMed

    Wakame, Koji; Okawa, Hiroshi; Komatsu, Ken-Ich; Nakata, Akifumi; Sato, Keisuke; Ingawa, Hiroyuki; Kohchi, Chie; Nishizawa, Takashi; Soma, Gen-Ichiro

    2016-07-01

    The lipopolysaccharide (LPS)-like compound derived from Pantoea agglomerans (immunopotentiator from Pantoea agglomerans 1 (IP-PA1)) has been used not only as dietary supplement or cosmetic for humans, but also by Japanese veterinarians as an anti-tumor, anti-allergy, "keep a fine coat of fur" and hair growth-promoting functional food for dogs and cats. In the present study, we focused on the hair growth-promoting effects of IP-PA1 on a hair-shaved animal model and its mechanism of action. We also investigated its potential on gene expression after stimulating human dermal papilla cells with IP-PA1. The hair on the back of a C3H/HeN mouse was shaved and IP-PA1 was orally administered or applied to the skin. The status of hair growth was observed and recorded for 14 days. Skin was collected and histological tissue examination was performed with respect to hair growth status using hematoxylin and eosin staining. After IP-PA1 administration (2 and 10 μg/ml) to human dermal papilla cell culture system for 24 h, fibroblast growth factor-7 (FGF-7) and vascular endothelial growth factor (VEGF) mRNA expression were measured using real-time polymerase chain reaction (PCR) analysis. IP-PA1, when given orally, showed a tendency to promote hair growth in mice. In addition, skin application also significantly promoted hair growth, while histopathological examinations further demonstrated hair elongation from dermal papilla cells. In the human dermal papilla cell culture system, significant FGF-7 and VEGF mRNA expressions were observed (p<0.05). An underlying mechanism of gene expression by which IP-PA1 promotes hair growth was suggested to be different from that of medicine and traditional hair tonics, such as minoxidil and adenosine. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  5. MicroRNA‐199b Modulates Vascular Cell Fate During iPS Cell Differentiation by Targeting the Notch Ligand Jagged1 and Enhancing VEGF Signaling

    PubMed Central

    Chen, Ting; Kelaini, Sophia; Cochrane, Amy; Guha, Shaunta T.; Hu, Yanhua; Stitt, Alan W.; Xu, Qingbo

    2015-01-01

    Abstract Aims: Recent ability to derive endothelial cells (ECs) from induced pluripotent stem (iPS) cells holds a great therapeutic potential for personalized medicine and stem cell therapy. We aimed that better understanding of the complex molecular signals that are evoked during iPS cell differentiation toward ECs may allow specific targeting of their activities to enhance cell differentiation and promote tissue regeneration. Methods and Results: In this study, we have generated mouse iPS cells from fibroblasts using established protocol. When iPS cells were cultivated on type IV mouse collagen‐coated dishes in differentiation medium, cell differentiation toward vascular lineages were observed. To study the molecular mechanisms of iPS cell differentiation, we found that miR‐199b is involved in EC differentiation. A step‐wise increase in expression of miR‐199 was detected during EC differentiation. Notably, miR‐199b targeted the Notch ligand JAG1, resulting in vascular endothelial growth factor (VEGF) transcriptional activation and secretion through the transcription factor STAT3. Upon shRNA‐mediated knockdown of the Notch ligand JAG1, the regulatory effect of miR‐199b was ablated and there was robust induction of STAT3 and VEGF during EC differentiation. Knockdown of JAG1 also inhibited miR‐199b‐mediated inhibition of iPS cell differentiation toward smooth muscle markers. Using the in vitro tube formation assay and implanted Matrigel plugs, in vivo, miR‐199b also regulated VEGF expression and angiogenesis. Conclusions: This study indicates a novel role for miR‐199b as a regulator of the phenotypic switch during vascular cell differentiation derived from iPS cells by regulating critical signaling angiogenic responses. Stem Cells 2015;33:1405–1418 PMID:25535084

  6. Maternal Attributions of Infant Behavior and Parenting in Toddlerhood Predict Teacher-Rated Internalizing Problems in Childhood.

    PubMed

    Wagner, Nicholas J; Gueron-Sela, Noa; Bedford, Rachael; Propper, Cathi

    2018-06-12

    Social-information-processing theories of parenting posit that parents' beliefs and attributions about their children's behaviors contribute to how parents interact with their children. The purpose of this study was to examine the associations between negative parenting attributions in infancy, harsh-intrusive parenting in toddlerhood, and children's internalizing problems (IPs) in early childhood. Using data from a diverse longitudinal study (n = 206), the current study used a structural equation modeling approach to test if mothers' negative attributions measured at 6 months predicted teacher ratings of children's IPs in 1st grade, as well as the extent to which observed harsh-intrusive parenting behaviors measured at ages 1, 2, and 3 years mediated this link. Maternal negative attributions in infancy predict more IPs in 1st grade, but this link becomes nonsignificant when observed harsh-intrusive parenting is included as a mediator. A significant indirect effect suggests that harsh-intrusive parenting mediates the association between early negative attributions and eventual IPs. Findings from this study identify harsh-intrusive parenting behaviors as one potential mechanism through which the effects of early attributions are carried forward to influence children's IPs. The developmental and clinical implications of these findings are discussed.

  7. Benthic invertebrate density, biomass, and instantaneous secondary production along a fifth-order human-impacted tropical river.

    PubMed

    Aguiar, Anna Carolina Fornero; Gücker, Björn; Brauns, Mario; Hille, Sandra; Boëchat, Iola Gonçalves

    2015-07-01

    The aim of this study was to assess land use effects on the density, biomass, and instantaneous secondary production (IP) of benthic invertebrates in a fifth-order tropical river. Invertebrates were sampled at 11 stations along the Rio das Mortes (upper Rio Grande, Southeast Brazil) in the dry and the rainy season 2010/2011. Invertebrates were counted, determined, and measured to estimate their density, biomass, and IP. Water chemical characteristics, sediment heterogeneity, and habitat structural integrity were assessed in parallel. Total invertebrate density, biomass, and IP were higher in the dry season than those in the rainy season, but did not differ significantly among sampling stations along the river. However, taxon-specific density, biomass, and IP differed similarly among sampling stations along the river and between seasons, suggesting that these metrics had the same bioindication potential. Variability in density, biomass, and IP was mainly explained by seasonality and the percentage of sandy sediment in the riverbed, and not directly by urban or agricultural land use. Our results suggest that the consistently high degradation status of the river, observed from its headwaters to mouth, weakened the response of the invertebrate community to specific land use impacts, so that only local habitat characteristics and seasonality exerted effects.

  8. [The protective role of postvaccinal immunity in mumps in children].

    PubMed

    Zheleznikova, G F; Ivanova, V V; Bekhtereva, M K; Gnilevskaia, Z U; Monakhova, N E; Novozhilova, E V; Goleva, O V; Sizemov, A N

    2000-01-01

    The immunological study of children with infectious parotitis (IP) without complications and with such complications as pancreatitis, meningitis or orchitis in the glandular form was carried out. In accordance with the previously proposed principle, 4 types of immune response (IR) were established on the basis of differences in initial resistance and the IR profile: cell-mediated immunity (types I and III) and humoral immunity (types II and IV). The patients included nonvaccinated children, as well as children vaccinated on epidemic indications, 3-6, 7-9, 10 and more years before infection. The comparative analysis of the number of IP cases with and without complications in the groups of children, divided according to their immunization history and the type of IR, revealed that postvaccinal immunity in children vaccinated on epidemic indications (less than a month ago) or 3-6 years before infection had protective potential, sufficient for the prevention of complicated forms of IP. Immunity obtained 7-9 years ago was effective for the protection from IP complications only in cell-mediated, but not humoral IR. Postvaccinal immunity obtained more than 10 years ago did not ensure the decrease in the occurrence of complicated forms of IP (in comparison with that in nonvaccinated patients) in children with any type of IR.

  9. Geothermal Exploration By Using Time Domain IP Method:Balikesir (Gure) And Canakkale (Geyikli) Cases From Turkey

    NASA Astrophysics Data System (ADS)

    Tezel, O.; Ozcep, F.

    2017-12-01

    Geothermal energy is heat derived from the earth. It is the thermal energy contained in the rock and fluid (that fills the fractures and pores within the rock) in the earth's crust. These resources are always at a temperature higher than 20°C. Geothermal energy requires no fuel, and is therefore virtually emission free and independent of fluctuations in fuel cost. Since a geothermal power plant doesn't rely on transient sources of energy, unlike, for example, wind turbines or solar panels, its capacity factor can be quite large. Induced polarization (IP) results at geothermal regions show prominent, extended low resistivity zones. Environmental-IP methods can assist in the assessment of the acid generating potential of waste rock and tailings from mine operations. Resistivity can be used to map contamination plumes. Resistivity and chargeability values were determined using the IP method on geothermal resources in Balikesir Güre (Turkey). In this study we found low resistance values and high chargeability values at the geothermal resource. Finally drilling and IP results were correlated to verify our findings. After the positive results of obtained data, a similar study was carried out in Geyikli Area (Canakkale) and a geothermal resource with 450C temperature of 5 lt/sec was explored at a depth of 970 m.

  10. Metabolic activation of 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine and DNA adduct formation depends on p53: Studies in Trp53(+/+),Trp53(+/-) and Trp53(-/-) mice.

    PubMed

    Krais, Annette M; Speksnijder, Ewoud N; Melis, Joost P M; Singh, Rajinder; Caldwell, Anna; Gamboa da Costa, Gonçalo; Luijten, Mirjam; Phillips, David H; Arlt, Volker M

    2016-02-15

    The expression of the tumor suppressor p53 can influence the bioactivation of, and DNA damage induced by, the environmental carcinogen benzo[a]pyrene, indicating a role for p53 in its cytochrome P450 (CYP)-mediated biotransformation. The carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), which is formed during the cooking of food, is also metabolically activated by CYP enzymes, particularly CYP1A2. We investigated the potential role of p53 in PhIP metabolism in vivo by treating Trp53(+/+), Trp53(+/-) and Trp53(-/-) mice with a single oral dose of 50 mg/kg body weight PhIP. N-(Deoxyguanosin-8-yl)-2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP-C8-dG) levels in DNA, measured by liquid chromatography-tandem mass spectrometry, were significantly lower in liver, colon, forestomach and glandular stomach of Trp53(-/-) mice compared to Trp53(+/+) mice. Lower PhIP-DNA adduct levels in the livers of Trp53(-/-) mice correlated with lower Cyp1a2 enzyme activity (measured by methoxyresorufin-O-demethylase activity) in these animals. Interestingly, PhIP-DNA adduct levels were significantly higher in kidney and bladder of Trp53(-/-) mice compared to Trp53(+/+) mice, which was accompanied by higher sulfotransferase (Sult) 1a1 protein levels and increased Sult1a1 enzyme activity (measured by 2-naphthylsulfate formation from 2-naphthol) in kidneys of these animals. Our study demonstrates a role for p53 in the metabolism of PhIP in vivo, extending previous results on a novel role for p53 in xenobiotic metabolism. Our results also indicate that the impact of p53 on PhIP biotransformation is tissue-dependent and that in addition to Cyp1a enzymes, Sult1a1 can contribute to PhIP-DNA adduct formation. © 2015 The Authors International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.

  11. Airborne Satcom Terminal Research at NASA Glenn

    NASA Technical Reports Server (NTRS)

    Hoder, Doug; Zakrajsek, Robert

    2002-01-01

    NASA Glenn has constructed an airborne Ku-band satellite terminal, which provides wideband full-duplex ground-aircraft communications. The terminal makes use of novel electronically-steered phased array antennas and provides IP connectivity to and from the ground. The satcom terminal communications equipment may be easily changed whenever a new configuration is required, enhancing the terminal's versatility.

  12. Structural and electronic properties of Aun-xPtx (n = 2-14; x ⩽ n) clusters: The density functional theory investigation

    NASA Astrophysics Data System (ADS)

    Yuan, H. K.; Kuang, A. L.; Tian, C. L.; Chen, H.

    2014-03-01

    The structural evolutions and electronic properties of bimetallic Aun-xPtx (n = 2-14; x ⩽ n) clusters are investigated by using the density functional theory (DFT) with the generalized gradient approximation (GGA). The monatomic doping Aun-1Pt clusters are emphasized and compared with the corresponding pristine Aun clusters. The results reveal that the planar configurations are favored for both Aun-1Pt and Aun clusters with size up to n = 13, and the former often employ the substitution patterns based on the structures of the latter. The most stable clusters are Au6 and Au6Pt, which adopt regular planar triangle (D3h) and hexagon-ring (D6h) structures and can be regarded as the preferential building units in designing large clusters. For Pt-rich bimetallic clusters, their structures can be obtained from the substitution of Pt atoms by Au atoms from the Ptn structures, where Pt atoms assemble together and occupy the center yet Au atoms prefer the apex positions showing a segregation effect. With respect to pristine Au clusters, AunPt clusters exhibit somewhat weaker and less pronounced odd-even oscillations in the highest occupied and lowest unoccupied molecular-orbital gaps (HOMO-LUMO gap), electron affinity (EA), and ionization potential (IP) due to the partially released electron pairing effect. The analyses of electronic structure indicate that Pt atoms in AuPt clusters would delocalize their one 6s and one 5d electrons to contribute the electronic shell closure. The sp-d hybridizations as well as the d-d interactions between the host Au and dopant Pt atoms result in the enhanced stabilities of AuPt clusters.

  13. Error Correction for the JLEIC Ion Collider Ring

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

    Wei, Guohui; Morozov, Vasiliy; Lin, Fanglei

    2016-05-01

    The sensitivity to misalignment, magnet strength error, and BPM noise is investigated in order to specify design tolerances for the ion collider ring of the Jefferson Lab Electron Ion Collider (JLEIC) project. Those errors, including horizontal, vertical, longitudinal displacement, roll error in transverse plane, strength error of main magnets (dipole, quadrupole, and sextupole), BPM noise, and strength jitter of correctors, cause closed orbit distortion, tune change, beta-beat, coupling, chromaticity problem, etc. These problems generally reduce the dynamic aperture at the Interaction Point (IP). According to real commissioning experiences in other machines, closed orbit correction, tune matching, beta-beat correction, decoupling, andmore » chromaticity correction have been done in the study. Finally, we find that the dynamic aperture at the IP is restored. This paper describes that work.« less

  14. Induced Polarization Surveying for Acid Rock Screening in Highway Design

    NASA Astrophysics Data System (ADS)

    Butler, K. E.; Al, T.; Bishop, T.

    2004-05-01

    Highway and pipeline construction agencies have become increasingly vigilant in their efforts to avoid cutting through sulphide-bearing bedrock that has potential to produce acid rock drainage. Blasting and fragmentation of such rock increases the surface area available for sulphide oxidation and hence increases the risk of acid rock drainage unless the rock contains enough natural buffering capacity to neutralize the pH. In December, 2001, the New Brunswick Department of Transportation (NBOT) sponsored a field trial of geophysical surveying in order to assess its suitability as a screening tool for locating near-surface sulphides along proposed highway alignments. The goal was to develop a protocol that would allow existing programs of drilling and geochemical testing to be targeted more effectively, and provide design engineers with the information needed to reduce rock cuts where necessary and dispose of blasted material in a responsible fashion. Induced polarization (IP) was chosen as the primary geophysical method given its ability to detect low-grade disseminated mineralization. The survey was conducted in dipole-dipole mode using an exploration-style time domain IP system, dipoles 8 to 25 m in length, and six potential dipoles for each current dipole location (i.e. n = 1 - 6). Supplementary information was provided by resistivity and VLF-EM surveys sensitive to lateral changes in electrical conductivity, and by magnetic field surveying chosen for its sensitivity to the magnetic susceptibility of pyrrhotite. Geological and geochemical analyses of samples taken from several IP anomalies located along 4.3 line-km of proposed highway confirmed the effectiveness of the screening technique. IP pseudosections from a region of metamorphosed shales and volcaniclastic rocks identified discrete, well-defined mineralized zones. Stronger, overlapping, and more laterally extensive IP anomalies were observed over a section of graphitic and sulphide-bearing metasedimentary rocks. Attempts to use spectral IP characteristics to determine relative abundances of sulphides and graphite were not conclusive. The overall effectiveness of the screening technique however encouraged NBDOT to apply it to an additional 50 km of planned rock cuts along the corridor selected for the new Trans-Canada Highway.

  15. Role of nitric oxide of the median preoptic nucleus (MnPO) in the alterations of salivary flow, arterial pressure and heart rate induced by injection of pilocarpine into the MnPO and intraperitoneally.

    PubMed

    Saad, Wilson A; Guarda, I F M S; Camargo, L A A; Santos, T A F B; Guarda, R S; Saad, Willian A; Simões, S; Rodrigues, J Antunes

    2003-07-01

    We investigated the effect of L-NAME, a nitric oxide (NO) inhibitor and sodium nitroprusside (SNP), an NO-donating agent, on pilocarpine-induced alterations in salivary flow, mean arterial blood pressure (MAP) and heart rate (HR) in rats. Male Holtzman rats (250-300 g) were implanted with a stainless steel cannula directly into the median preoptic nucleus (MnPO). Pilocarpine (10, 20, 40, 80, 160 g) injected into the MnPO induced an increase in salivary secretion (P<0.01). Pilocarpine (1, 2, 4, 8, 16 mg/kg) ip also increased salivary secretion (P<0.01). Injection of L-NAME (40 g) into the MnPO prior to pilocarpine (10, 20, 40, 80, 160 g) injected into the MnPO or ip (1, 2, 4, 8, 16 mg/kg) increased salivary secretion (P<0.01). SNP (30 g) injected into the MnPO or ip prior to pilocarpine attenuated salivary secretion (P<0.01). Pilocarpine (40 g) injection into the MnPO increased MAP and decreased HR (P<0.01). Pilocarpine (4 mg/kg body weight) ip produced a decrease in MAP and an increase in HR (P<0.01). Injection of L-NAME (40 g) into the MnPO prior to pilocarpine potentiated the increase in MAP and reduced HR (P<0.01). SNP (30 g) injected into the MnPO prior to pilocarpine attenuated (100%) the effect of pilocarpine on MAP, with no effect on HR. Administration of L-NAME (40 g) into the MnPO potentiated the effect of pilocarpine injected ip. SNP (30 g) injected into the MnPO attenuated the effect of ip pilocarpine on MAP and HR. The present study suggests that in the rat MnPO 1) NO is important for the effects of pilocarpine on salivary flow, and 2) pilocarpine interferes with blood pressure and HR (side effects of pilocarpine), that is attenuated by NO.

  16. Relativistic electron kinetic effects on laser diagnostics in burning plasmas

    NASA Astrophysics Data System (ADS)

    Mirnov, V. V.; Den Hartog, D. J.

    2018-02-01

    Toroidal interferometry/polarimetry (TIP), poloidal polarimetry (PoPola), and Thomson scattering systems (TS) are major optical diagnostics being designed and developed for ITER. Each of them relies upon a sophisticated quantitative understanding of the electron response to laser light propagating through a burning plasma. Review of the theoretical results for two different applications is presented: interferometry/polarimetry (I/P) and polarization of Thomson scattered light, unified by the importance of relativistic (quadratic in vTe/c) electron kinetic effects. For I/P applications, rigorous analytical results are obtained perturbatively by expansion in powers of the small parameter τ = Te/me c2, where Te is electron temperature and me is electron rest mass. Experimental validation of the analytical models has been made by analyzing data of more than 1200 pulses collected from high-Te JET discharges. Based on this validation the relativistic analytical expressions are included in the error analysis and design projects of the ITER TIP and PoPola systems. The polarization properties of incoherent Thomson scattered light are being examined as a method of Te measurement relevant to ITER operational regimes. The theory is based on Stokes vector transformation and Mueller matrices formalism. The general approach is subdivided into frequency-integrated and frequency-resolved cases. For each of them, the exact analytical relativistic solutions are presented in the form of Mueller matrix elements averaged over the relativistic Maxwellian distribution function. New results related to the detailed verification of the frequency-resolved solutions are reported. The precise analytic expressions provide output much more rapidly than relativistic kinetic numerical codes allowing for direct real-time feedback control of ITER device operation.

  17. Induced pluripotent stem (iPS) cells from human fetal stem cells.

    PubMed

    Guillot, Pascale V

    2016-02-01

    Pluripotency defines the ability of stem cells to differentiate into all the lineages of the three germ layers and self-renew indefinitely. Somatic cells can regain the developmental potential of embryonic stem cells following ectopic expression of a set of transcription factors or, in certain circumstances, via modulation of culture conditions and supplementation with small molecule, that is, induced pluripotent stem (iPS) cells. Here, we discuss the use of fetal tissues for reprogramming, focusing in particular on stem cells derived from human amniotic fluid, and the development of chemical reprogramming. We next address the advantages and disadvantages of deriving pluripotent cells from fetal tissues and the potential clinical applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Abnormalities in human pluripotent cells due to reprogramming mechanisms

    PubMed Central

    Ma, Hong; Morey, Robert; O’Neil, Ryan C.; He, Yupeng; Daughtry, Brittany; Schultz, Matthew D.; Hariharan, Manoj; Nery, Joseph R.; Castanon, Rosa; Sabatini, Karen; Thiagarajan, Rathi D.; Tachibana, Masahito; Kang, Eunju; Tippner-Hedges, Rebecca; Ahmed, Riffat; Gutierrez, Nuria Marti; Van Dyken, Crystal; Polat, Alim; Sugawara, Atsushi; Sparman, Michelle; Gokhale, Sumita; Amato, Paula; Wolf, Don P.; Ecker, Joseph R.; Laurent, Louise C.; Mitalipov, Shoukhrat

    2016-01-01

    Human pluripotent stem cells hold potential for regenerative medicine, but available cell types have significant limitations. Although embryonic stem cells (ES cells) from in vitro fertilized embryos (IVF ES cells) represent the ‘gold standard’, they are allogeneic to patients. Autologous induced pluripotent stem cells (iPS cells) are prone to epigenetic and transcriptional aberrations. To determine whether such abnormalities are intrinsic to somatic cell reprogramming or secondary to the reprogramming method, genetically matched sets of human IVF ES cells, iPS cells and nuclear transfer ES cells (NT ES cells) derived by somatic cell nuclear transfer (SCNT) were subjected to genome-wide analyses. Both NT ES cells and iPS cells derived from the same somatic cells contained comparable numbers of de novo copy number variations. In contrast, DNA methylation and transcriptome profiles of NT ES cells corresponded closely to those of IVF ES cells, whereas iPS cells differed and retained residual DNA methylation patterns typical of parental somatic cells. Thus, human somatic cells can be faithfully reprogrammed to pluripotency by SCNT and are therefore ideal for cell replacement therapies. PMID:25008523

  19. Identification of potential target genes of ROR-alpha in THP1 and HUVEC cell lines.

    PubMed

    Gulec, Cagri; Coban, Neslihan; Ozsait-Selcuk, Bilge; Sirma-Ekmekci, Sema; Yildirim, Ozlem; Erginel-Unaltuna, Nihan

    2017-04-01

    ROR-alpha is a nuclear receptor, activity of which can be modulated by natural or synthetic ligands. Due to its possible involvement in, and potential therapeutic target for atherosclerosis, we aimed to identify ROR-alpha target genes in monocytic and endothelial cell lines. We performed chromatin immunoprecipitation (ChIP) followed by tiling array (ChIP-on-chip) for ROR-alpha in monocytic cell line THP1 and endothelial cell line HUVEC. Following bioinformatic analysis of the array data, we tested four candidate genes in terms of dependence of their expression level on ligand-mediated ROR-alpha activity, and two of them in terms of promoter occupancy by ROR-alpha. Bioinformatic analyses of ChIP-on-chip data suggested that ROR-alpha binds to genomic regions near the transcription start site (TSS) of more than 3000 genes in THP1 and HUVEC. Potential ROR-alpha target genes in both cell types seem to be involved mainly in membrane receptor activity, signal transduction and ion transport. While SPP1 and IKBKA were shown to be direct target genes of ROR-alpha in THP1 monocytes, inflammation related gene HMOX1 and heat shock protein gene HSPA8 were shown to be potential target genes of ROR-alpha. Our results suggest that ROR-alpha may regulate signaling receptor activity, and transmembrane transport activity through its potential target genes. ROR-alpha seems also to play role in cellular sensitivity to environmental substances like arsenite and chloroprene. Although, the expression analyses have shown that synthetic ROR-alpha ligands can modulate some of potential ROR-alpha target genes, functional significance of ligand-dependent modulation of gene expression needs to be confirmed with further analyses. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Locomotor Stimulant and Rewarding Effects of Inhaling Methamphetamine, MDPV, and Mephedrone via Electronic Cigarette-Type Technology

    PubMed Central

    Nguyen, Jacques D; Aarde, Shawn M; Cole, Maury; Vandewater, Sophia A; Grant, Yanabel; Taffe, Michael A

    2016-01-01

    Although inhaled exposure to drugs is a prevalent route of administration for human substance abusers, preclinical models that incorporate inhaled exposure to psychomotor stimulants are not commonly available. Using a novel method that incorporates electronic cigarette-type technology to facilitate inhalation, male Wistar rats were exposed to vaporized methamphetamine (MA), 3,4-methylenedioxypyrovalerone (MDPV), and mephedrone (4-methylmethcathinone) in propylene glycol vehicle using concentrations ranging from 12.5 to 200 mg/ml. Rats exhibited increases in spontaneous locomotor activity, measured by implanted radiotelemetry, following exposure to methamphetamine (12.5 and 100 mg/ml), MDPV (25, 50, and 100 mg/ml), and mephedrone (200 mg/ml). Locomotor effects were blocked by pretreatment with the dopamine D1-like receptor antagonist SCH23390 (10 μg/kg, intraperitoneal (i.p.)). MA and MDPV vapor inhalation also altered activity on a running wheel in a biphasic manner. An additional group of rats was trained on a discrete trial intracranial self-stimulation (ICSS) procedure interpreted to assess brain reward status. ICSS-trained rats that received vaporized MA, MDPV, or mephedrone exhibited a significant reduction in threshold of ICSS reward compared with vehicle. The effect of vapor inhalation of the stimulants was found comparable to the locomotor and ICSS threshold-reducing effects of i.p. injection of mephedrone (5.0 mg/kg), MA (0.5–1.0 mg/kg), or MDPV (0.5–1.0 mg/kg). These data provide robust validation of e-cigarette-type technology as a model for inhaled delivery of vaporized psychostimulants. Finally, these studies demonstrate the potential for human use of e-cigarettes to facilitate covert use of a range of psychoactive stimulants. Thus, these devices pose health risks beyond their intended application for the delivery of nicotine. PMID:27277119

  1. Correlation consistent basis sets for lanthanides: The atoms La–Lu

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

    Lu, Qing; Peterson, Kirk A., E-mail: kipeters@wsu.edu

    Using the 3rd-order Douglas-Kroll-Hess (DKH3) Hamiltonian, all-electron correlation consistent basis sets of double-, triple-, and quadruple-zeta quality have been developed for the lanthanide elements La through Lu. Basis sets designed for the recovery of valence correlation (defined here as 4f5s5p5d6s), cc-pVnZ-DK3, and outer-core correlation (valence + 4s4p4d), cc-pwCVnZ-DK3, are reported (n = D, T, and Q). Systematic convergence of both Hartree-Fock and correlation energies towards their respective complete basis set (CBS) limits are observed. Benchmark calculations of the first three ionization potentials (IPs) of La through Lu are reported at the DKH3 coupled cluster singles and doubles with perturbative triples,more » CCSD(T), level of theory, including effects of correlation down through the 4s electrons. Spin-orbit coupling is treated at the 2-component HF level. After extrapolation to the CBS limit, the average errors with respect to experiment were just 0.52, 1.14, and 4.24 kcal/mol for the 1st, 2nd, and 3rd IPs, respectively, compared to the average experimental uncertainties of 0.03, 1.78, and 2.65 kcal/mol, respectively. The new basis sets are also used in CCSD(T) benchmark calculations of the equilibrium geometries, atomization energies, and heats of formation for Gd{sub 2}, GdF, and GdF{sub 3}. Except for the equilibrium geometry and harmonic frequency of GdF, which are accurately known from experiment, all other calculated quantities represent significant improvements compared to the existing experimental quantities. With estimated uncertainties of about ±3 kcal/mol, the 0 K atomization energies (298 K heats of formation) are calculated to be (all in kcal/mol): 33.2 (160.1) for Gd{sub 2}, 151.7 (−36.6) for GdF, and 447.1 (−295.2) for GdF{sub 3}.« less

  2. Quantification of in vivo site-specific Asp isomerization and Asn deamidation of mAbs in animal serum using IP-LC-MS.

    PubMed

    Mehl, John T; Sleczka, Bogdan G; Ciccimaro, Eugene F; Kozhich, Alexander T; Gilbertson, Deb G; Vuppugalla, Ragini; Huang, Christine S; Stevens, Brenda; Mo, Jingjie; Deyanova, Ekaterina G; Wang, Yun; Huang, Richard Yc; Chen, Guodong; Olah, Timothy V

    2016-08-01

    Isomerization of aspartic acid and deamidation of asparagine are two common amino acid modifications that are of particular concern if located within the complementarity-determining region of therapeutic antibodies. Questions arise as to the extent of modification occurring in circulation due to potential exposure of the therapeutic antibody to different pH regimes. To enable evaluation of site-specific isomerization and deamidation of human mAbs in vivo, immunoprecipitation (IP) has been combined with LC-MS providing selective enrichment, separation and detection of naive and modified forms of tryptic peptides comprising complementarity-determining region sequences. IP-LC-MS can be applied to simultaneously quantify in vivo drug concentrations and measure the extent of isomerization or deamidation in PK studies conducted during the drug discovery stage.

  3. Water soluble vitamin E (TMG) as a radioprotector.

    PubMed

    Nair, Cherupally Krishnan K; Devi, Pathirissery Uma; Shimanskaya, R; Kunugita, N; Murase, Hironobu; Gu, Yeun-Hwa; Kagiya, Tsutomu V

    2003-12-01

    Tocopherol monoglucoside (TMG), a water soluble derivative of vitamin E offers protection against deleterious effects of ionizing radiation, both under in vivo and in vitro conditions, to biological systems. TMG was found to be a potent antioxidant and an effective free radical scavenger. It forms a phenoxyl radical similar to trolox upon reaction with various one-electron oxidants. TMG protected DNA from radiation-induced strand breaks. It also protected thymine glycol formation induced by gamma-radiation. Gamma-radiation-induced loss of viability of EL-tumor cells and peroxidation of lipids in microsomal and mitochondrial membranes were prevented by TMG. TMG was nontoxic to mice when administered orally up to 7.0 g/kg body weight. The LD50 dose of TMG for ip administration in mice was 1.15 g/kg body wt. In rats, following oral and ip administration of TMG, the absorption (distribution) half lives were 5.8 and 3.0 min respectively and elimination half lives were 6.7 and 3.1 min respectively. Embryonic mortality resulting from exposure of pregnant mice to ionizing radiation (2 Gy) was reduced by 75% by ip administration of TMG (0.6 g/kg, body wt) prior to irradiation. TMG offered protection to mice against whole body gamma-radiation-induced lethality and weight loss. The LD50(30) of mice increased from 6 to 6.72 Gy upon post irradiation administration of a single dose of TMG (0.6 g/kg, body wt) by ip.

  4. Investigations on the effects of mouthrinses on the colour stability and surface roughness of different dental bioceramics

    PubMed Central

    Varol, Osman

    2017-01-01

    PURPOSE In this study, three bioceramic materials, [IPS Empress CAD (Ivoclar), IPS e.max CAD (Ivoclar), and Lava Ultimate CAD (3M ESPE)] were treated with three commercial mouthrinses [Listerine, Tantum Verde, and Klorhex]; and changes in colour reflectance and surface roughness values were then quantitatively assessed. MATERIALS AND METHODS One hundred and twenty ceramic samples, with dimensions of 2 × 12 × 14 mm, were prepared and divided into nine sample groups, except three control samples. The samples were immersed in the mouthrinse solutions for 120 hrs, and changes in colour reflectance and surface roughness values were measured by UV light spectrophotometry (Vita Easyshade; VITA Zahnfabrik) and by profilometer device (MitutoyoSurftest SJ-301), respectively. The change of surface roughness was inspected by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). RESULTS There was a positive correlation between the ΔE and increase in the surface roughness. Two of the ceramic materials, IPS Empress and Lava Ultimate, were affected significantly by the treatment of the mouthrinse solutions (P<.05). The most affecting solution was Tantum Verde and the most affected material was Lava Ultimate. As expected, the most resistant material to ΔE and chemical corrosion was IPS e max CAD among the materials used. CONCLUSION This work implied that mouthrinse with lower alcohol content had less deteriorating effect on colour and on the surface morphology of the bioceramic materials. PMID:28680552

  5. Interfacial characterization of ceramic core materials with veneering porcelain for all-ceramic bi-layered restorative systems.

    PubMed

    Tagmatarchis, Alexander; Tripodakis, Aris-Petros; Filippatos, Gerasimos; Zinelis, Spiros; Eliades, George

    2014-01-01

    The aim of the study was to characterize the elemental distribution at the interface between all-ceramic core and veneering porcelain materials. Three groups of all-ceramic cores were selected: A) Glass-ceramics (Cergo, IPS Empress, IPS Empress 2, e-max Press, Finesse); B) Glass-infiltrated ceramics (Celay Alumina, Celay Zirconia) and C) Densely sintered ceramics (Cercon, Procera Alumina, ZirCAD, Noritake Zirconia). The cores were combined with compatible veneering porcelains and three flat square test specimens were produced for each system. The core-veneer interfaces were examined by scanning electron microscopy and energy dispersive x-ray microanalysis. The glass-ceramic systems showed interfacial zones reach in Si and O, with the presence of K, Ca, Al in core and Ca, Ce, Na, Mg or Al in veneer material, depending on the system tested. IPS Empress and IPS Empress 2 demonstrated distinct transitional phases at the core-veneer interface. In the glassinfiltrated systems, intermixing of core (Ce, La) with veneer (Na, Si) elements occurred, whereas an abrupt drop of the core-veneer elemental concentration was documented at the interfaces of all densely sintered ceramics. The results of the study provided no evidence of elemental interdiffusion at the core-veneer interfaces in densely sintered ceramics, which implies lack of primary chemical bonding. For the glass-containing systems (glassceramics and glass-infiltrated ceramics) interdiffusion of the glass-phase seems to play a critical role in establishing a primary bonding condition between ceramic core and veneering porcelain.

  6. Flexural strength and reliability of monolithic and trilayer ceramic structures obtained by the CAD-on technique.

    PubMed

    Basso, G R; Moraes, R R; Borba, M; Griggs, J A; Della Bona, A

    2015-12-01

    To evaluate the flexural strength, Weibull modulus, fracture toughness, and failure behavior of ceramic structures obtained by the CAD-on technique, testing the null hypothesis that trilayer structures show similar properties to monolithic structures. Bar-shaped (1.8mm×4mm×16mm) monolithic specimens of zirconia (IPS e.max ZirCAD - Ivoclar Vivadent) and trilayer specimens of zirconia/fusion ceramic/lithium dissilicate (IPS e.max ZirCAD/IPS e.max CAD Crystall./Connect/IPS e.max CAD, Ivoclar Vivadent) were fabricated (n=30). Specimens were tested in flexure in 37°C deionized water using a universal testing machine at a crosshead speed of 0.5mm/min. Failure loads were recorded, and the flexural strength values were calculated. Fractography principles were used to examine the fracture surfaces under optical and scanning electron microscopy. Data were statistically analyzed using Student's t-test and Weibull statistics (α=0.05). Monolithic and trilayer specimens showed similar mean flexural strengths, characteristic strengths, and Weibull moduli. Trilayer structures showed greater mean critical flaw and fracture toughness values than monolithic specimens (p<0.001). Most critical flaws in the trilayer groups were located on the Y-TZP surface subjected to tension and propagated catastrophically. Trilayer structures showed no flaw deflection at the interface. Considering the CAD-on technique, the trilayer structures showed greater fracture toughness than the monolithic zirconia specimens. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  7. Effect of etching time and resin bond on the flexural strength of IPS e.max Press glass ceramic.

    PubMed

    Xiaoping, Luo; Dongfeng, Ren; Silikas, Nick

    2014-12-01

    To evaluate the effect of hydrofluoric acid (HFA) etching time and resin cement bond on the flexural strength of IPS e.max(®) Press glass ceramic. Two hundred and ten bars, 25mm×3mm×2mm, were made from IPS e.max(®) Press ingots through lost-wax, hot-pressed ceramic fabrication technology and randomly divided into five groups with forty-two per group after polishing. The ceramic surfaces of different groups were etched by 9.5% hydrofluoric acid gel for 0, 20, 40, 60 and 120s respectively. Two specimens of each group were selected randomly to examine the surface roughness and 3-dimensional topography with atomic force microscope (AFM), and microstructure was analyzed by the field emission scanning electron microscope (FE-SEM). Then each group were subdivided into two subgroups (n=20). One subgroup of this material was selected to receive a thin (approximately 0.1mm) layer of resin luting agent (Variolink N) whereas the other subgroup remained unaltered. Half of subgroup's specimens were thermocycled 10,000 times before a 3-point bending test in order to determine the flexural strength. Interface between resin cement and ceramic was examined with field emission scanning electronic microscope. Roughness values increased with increasing etching time. The mean flexural strength values of group 0s, 20s, 40s, 60s and 120s were 384±33, 347±43, 330±53, 327±67 and 317±41MPa respectively. Increasing HF etching times reduced the mean flexural strength (p<0.05). However, the mean flexural strength of each group, except group 0s, increased significantly to 420±31, 435±50, 400±39 and 412±58MPa after the application of dual-curing resin cement. In the present investigation, no significant differences after thermocycling on the flexural strengths were evident. Overtime HF etching could have a wakening effect on IPS e.max(®) Press glass ceramic, but resin cement bonding to appropriately etched surface would strengthen the dental ceramic. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  8. [Endonasal micro-endoscopic resection of sinonasal inverted papilloma].

    PubMed

    Minovi, A; Kollert, M; Draf, W; Bockmühl, U

    2006-06-01

    The goal of this study was to assess the potentials and limitations of endonasal micro-endoscopic surgery in the treatment of sinonasal inverted papilloma (IP) and to demonstrate long-term results. From 1989 to 2005, 64 patients underwent resection of IP via an endonasal approach using either the endoscope or microscope. Charts were reviewed retrospectively for presenting symptoms, radiological and intraoperative data. All patients were followed by endoscopic and MRI control during a period of up to 174 months, median follow-up was 78 months. Our study group consisted of 26 male and 38 female patients with an average age of 54.3 years. The majority of the patients (67 %) complained of unilateral nasal obstruction. 52 patients (81 %) were referred for primary surgery. In 12 cases (19 %) recurrent tumors were operated. According to the Krouse classification for IP the tumors were staged as T1 = 11 (17 %) cases, T2 = 37 (58 %) and T3 = 14 (22 %). In two patients a squamous cell carcinoma was associated with an IP ( = T4 stage). Most tumors were localized within the nasal cavity (72 %) or the anterior ethmoid (62 %). In 10 patients an infiltration of the bony skull base was present. During the follow-up period 6 patients developed recurrencies corresponding to an overall recurrence rate of 9.4 %. The advances in endonasal micro-endoscopic surgery allow both safe and effective removal of IP with low morbidity, and therefore it should be the approach of the first choice. The osteoplastic approach combined with endonasal surgery is suitable in far lateral located IP. Close follow-up is mandatory to ensure the surgical success.

  9. Economic, Labor, and Regulatory Moderators of the Effect of Individual Placement and Support Among People With Severe Mental Illness: A Systematic Review and Meta-analysis.

    PubMed

    Metcalfe, Justin D; Drake, Robert E; Bond, Gary R

    2018-01-13

    As Individual Placement and Support (IPS) has become the international standard for vocational rehabilitation of adults with serious mental illness, researchers must consider the relationship between IPS and local environments. This meta-analysis used mixed-effects meta-regressions to assess the impact of site-level moderators on the likelihood that IPS recipients, compared with recipients of alternative vocational services, achieved competitive employment. Potential moderators included change in gross domestic product (GDP), local unemployment and unionization rates, and indices describing employment protection regulations, level of disability benefits compensation, and efforts to integrate people with disabilities into the workforce. Regulatory moderators represent facilitators and barriers to employment that may reinforce or detract from the effectiveness of IPS. Across 30 sites drawn from 21 randomized controlled trials in 12 countries (33% in the United States), IPS recipients were 2.31 (95% CI 1.99-2.69) times more likely to find competitive employment than recipients of alternative vocational rehabilitation services. The significant competitive-employment rate advantage of IPS over control services increased in the presence of weaker employment protection legislation and integration efforts, and less generous disability benefits. Policy makers should recognize and account for the fact that labor and disability regulations can create an arrangement of incentives that reduces the relative efficacy of supported employment. © The Author(s) 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  10. Ripk3 regulates cardiac microvascular reperfusion injury: The role of IP3R-dependent calcium overload, XO-mediated oxidative stress and F-action/filopodia-based cellular migration.

    PubMed

    Zhou, Hao; Wang, Jin; Zhu, Pingjun; Hu, Shunying; Ren, Jun

    2018-05-01

    Ripk3-mediated cellular apoptosis is a major contributor to the pathogenesis of myocardial ischemia reperfusion (IR) injury. However, the mechanisms by which Ripk3 influences microvascular homeostasis and endothelial apoptosis are not completely understood. In this study, loss of Ripk3 inhibited endothelial apoptosis, alleviated luminal swelling, maintained microvasculature patency, reduced the expression of adhesion molecules and limited the myocardial inflammatory response. In vitro, Ripk3 deficiency protected endothelial cells from apoptosis and migratory arrest induced by HR injury. Mechanistically, Ripk3 had the ability to migrate onto the endoplasmic reticulum (ER), leading to ER damage, as evidenced by increased IP3R and XO expression. The higher IP3R content was associated with cellular calcium overload, and increased XO expression was involved in cellular oxidative injury. Furthermore, IP3R-mediated calcium overload and XO-dependent oxidative damage were able to initiate cellular apoptosis. More importantly, IP3R and XO also caused F-actin degradation into G-actin via post-transcriptional modification of cofilin, impairing the formation of the filopodia and limiting the migratory response of endothelial cells. Altogether, our data confirmed that Ripk3 was involved in microvascular IR injury via regulation of IP3R-mediated calcium overload, XO-dependent oxidative damage and filopodia-related cellular migration, ultimately leading to endothelial apoptosis and migratory inhibition. These findings provide a potential target for treating cardiac microcirculatory IR injury. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Reaching for mechanistic consensus across life kingdoms: structure and insights into catalysis of the myo-inositol-1-phosphate synthase (mIPS) from Archaeoglobus fulgidus.

    PubMed

    Stieglitz, Kimberly A; Yang, Hongying; Roberts, Mary F; Stec, Boguslaw

    2005-01-11

    myo-Inositol-1-phosphate synthase (mIPS) catalyzes the first step in the synthesis of l-myo-inositol-1-phosphate. We have solved and refined the structure of the mIPS from the hyperthermophilic sulfate reducer Archaeoglobus fulgidus at 1.9 A resolution. The enzyme crystallized from poly(ethylene glycol) in the P1 space group with one tetramer in the asymmetric unit and provided a view of the entire biologically active oligomer. Despite significant changes in sequence length and amino acid composition, the general architecture of the archaeal enzyme is similar to that of the eukaryotic mIPS from Saccharomyces cerevisiae and bacterial mIPS from Mycobacterium tuberculosis. The enhanced thermostability of the archaeal enzyme as compared to that from yeast is consistent with deletion of a number of surface loops that results in a significantly smaller protein. In the structure of the A. fulgidus mIPS, the active sites of all four subunits were fully ordered and contained NAD(+) and inorganic phosphate. The structure also contained a single metal ion (identified as K(+)) in two of the four subunits. The analysis of the electrostatic potential maps of the protein suggested the presence of a second metal-ion-binding site in close proximity to the first metal ion and NAD(+). The modeling of the substrate and known inhibitors suggests a critical role for the second metal ion in catalysis and provides insights into the common elements of the catalytic cycle in enzymes from different life kingdoms.

  12. Crystal structure of mitochondrial respiratory membrane protein complex II.

    PubMed

    Sun, Fei; Huo, Xia; Zhai, Yujia; Wang, Aojin; Xu, Jianxing; Su, Dan; Bartlam, Mark; Rao, Zihe

    2005-07-01

    The mitochondrial respiratory Complex II or succinate:ubiquinone oxidoreductase (SQR) is an integral membrane protein complex in both the tricarboxylic acid cycle and aerobic respiration. Here we report the first crystal structure of Complex II from porcine heart at 2.4 A resolution and its complex structure with inhibitors 3-nitropropionate and 2-thenoyltrifluoroacetone (TTFA) at 3.5 A resolution. Complex II is comprised of two hydrophilic proteins, flavoprotein (Fp) and iron-sulfur protein (Ip), and two transmembrane proteins (CybL and CybS), as well as prosthetic groups required for electron transfer from succinate to ubiquinone. The structure correlates the protein environments around prosthetic groups with their unique midpoint redox potentials. Two ubiquinone binding sites are discussed and elucidated by TTFA binding. The Complex II structure provides a bona fide model for study of the mitochondrial respiratory system and human mitochondrial diseases related to mutations in this complex.

  13. Spexin is a Novel Human Peptide that Reduces Adipocyte Uptake of Long Chain Fatty Acids and Causes Weight Loss in Rodents with Diet-induced Obesity*

    PubMed Central

    Walewski, José L.; Ge, Fengxia; Lobdell, Harrison; Levin, Nancy; Schwartz, Gary J.; Vasselli, Joseph; Pomp, Afons; Dakin, Gregory; Berk, Paul D.

    2014-01-01

    Objective Microarray studies identified Ch12:orf39 (Spexin) as the most dysregulated gene in obese human fat. Therefore we examined its role in obesity pathogenesis. Design and Methods Spexin effects on food intake, meal patterns, body weight, Respiratory Exchange Ratio (RER), and locomotor activity were monitored electronically in C57BL/6J mice or Wistar rats with dietary-induced obesity (DIO). Its effects on adipocyte [3H]-oleate uptake were determined. Results In humans, Spexin gene expression was down-regulated 14.9-fold in obese omental and subcutaneous fat. Circulating Spexin changed in parallel, correlating (r = −0.797) with Leptin. In rats, Spexin (35 μg/kg/day s.c) reduced caloric intake ~32% with corresponding weight loss. Meal patterns were unaffected. In mice, Spexin (25 μg/kg/day i.p.) significantly reduced the RER at night, and increased locomotion. Spexin incubation in vitro significantly inhibited facilitated fatty acid (FA) uptake into DIO mouse adipocytes. Conditioned taste aversion testing (70μg/kg/day i.p.) demonstrated no aversive Spexin effects. Conclusions Spexin gene expression is markedly down-regulated in obese human fat. The peptide produces weight loss in DIO rodents. Its effects on appetite and energy regulation are presumably central; those on adipocyte FA uptake appear direct and peripheral. Spexin is a novel hormone involved in weight regulation, with potential for obesity therapy. PMID:24550067

  14. Neurotrophic and antioxidant effects of silymarin comparable to 4-methylcatechol in protection against gentamicin-induced ototoxicity in guinea pigs.

    PubMed

    Draz, Eman I; Abdin, Amany A; Sarhan, Naglaa I; Gabr, Takwa A

    2015-04-01

    Despite that gentamicin is a very effective aminoglycoside, its potential ototoxicity which is of irreversible nature makes a challenge and limitation for its use. This study was designed to investigate possible neurotrophic and antioxidant effects of silymarin comparable to 4-methylcatechol in protection against gentamicin-induced ototoxicity. Twenty pigmented guinea pigs were divided into four equal groups, where group I served as normal control group. The other groups received gentamicin (120 mg/kg/day, ip) for 19 days where group II given vehicle of 1% CMC, group III and group IV were pre-treated 2h before gentamicin by 4-methylcatechol (10 μg/kg, ip) and silymarin (100mg/kg, oral gavage), respectively. The main findings indicated that silymarin exhibited restoration of nerve growth factor (NGF) levels and increased tropomyosin-related kinase receptors-A (Trk-A) m-RNA expression in cochlear tissue and preservation of hair cells of organ of Corti by scanning electron microscopy (SEM) with significant decrease in auditory brainstem response (ABR) threshold compared to 4-methylcatechol. Only silymarin caused significant amelioration in oxidative stress state by reducing malondialdehyde (MDA) levels and increasing catalase activity. Silymarin exerts superiority over 4-methylcatechol when recommended as protective agent against gentamicin ototoxicity based on its efficient neurotrophic and antioxidant activities. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  15. Reliable but Timesaving: In Search of an Efficient Quantum-chemical Method for the Description of Functional Fullerenes.

    PubMed

    Reis, H; Rasulev, B; Papadopoulos, M G; Leszczynski, J

    2015-01-01

    Fullerene and its derivatives are currently one of the most intensively investigated species in the area of nanomedicine and nanochemistry. Various unique properties of fullerenes are responsible for their wide range applications in industry, biology and medicine. A large pool of functionalized C60 and C70 fullerenes is investigated theoretically at different levels of quantum-mechanical theory. The semiempirial PM6 method, density functional theory with the B3LYP functional, and correlated ab initio MP2 method are employed to compute the optimized structures, and an array of properties for the considered species. In addition to the calculations for isolated molecules, the results of solution calculations are also reported at the DFT level, using the polarizable continuum model (PCM). Ionization potentials (IPs) and electron affinities (EAs) are computed by means of Koopmans' theorem as well as with the more accurate but computationally expensive ΔSCF method. Both procedures yield comparable values, while comparison of IPs and EAs computed with different quantum-mechanical methods shows surprisingly large differences. Harmonic vibrational frequencies are computed at the PM6 and B3LYP levels of theory and compared with each other. A possible application of the frequencies as 3D descriptors in the EVA (EigenVAlues) method is shown. All the computed data are made available, and may be used to replace experimental data in routine applications where large amounts of data are required, e.g. in structure-activity relationship studies of the toxicity of fullerene derivatives.

  16. Theoretical prediction of the band offsets at the ZnO/anatase TiO2 and GaN/ZnO heterojunctions using the self-consistent ab initio DFT/GGA-1/2 method.

    PubMed

    Fang, D Q; Zhang, S L

    2016-01-07

    The band offsets of the ZnO/anatase TiO2 and GaN/ZnO heterojunctions are calculated using the density functional theory/generalized gradient approximation (DFT/GGA)-1/2 method, which takes into account the self-energy corrections and can give an approximate description to the quasiparticle characteristics of the electronic structure of semiconductors. We present the results of the ionization potential (IP)-based and interfacial offset-based band alignments. In the interfacial offset-based band alignment, to get the natural band offset, we use the surface calculations to estimate the change of reference level due to the interfacial strain. Based on the interface models and GGA-1/2 calculations, we find that the valence band maximum and conduction band minimum of ZnO, respectively, lie 0.64 eV and 0.57 eV above those of anatase TiO2, while lie 0.84 eV and 1.09 eV below those of GaN, which agree well with the experimental data. However, a large discrepancy exists between the IP-based band offset and the calculated natural band offset, the mechanism of which is discussed. Our results clarify band alignment of the ZnO/anatase TiO2 heterojunction and show good agreement with the GW calculations for the GaN/ZnO heterojunction.

  17. New Epigenetic Therapeutic Intervention for Metastatic Breast Cancer

    DTIC Science & Technology

    2017-04-01

    papers as listed in 3.4B. Article Distinct Roles of Brd2 and Brd4 in Potentiating the Transcriptional Program for Th17 Cell Differentiation Graphical...this paper and include the following:d KEY RESOURCES TABLE d CONTACT FOR REAGENT AND RESOURCE SHARING d EXPERIMENTAL MODEL AND SUBJECT DETAILS d METHOD...Brd4, Smc1, Smc3, Nipbl, H3K27ac, H3K4me1 ChIP-seq data This paper GEO: GSE90788 and GSE63778 Other ChIP-seq data Ciofani et al., 2012 GEO: GSE40918

  18. Development of Novel Magnetic Metal Oxide Thin Films and Carbon Nanotube Materials for Potential Device Applications

    DTIC Science & Technology

    2016-05-09

    9 3 Fe/MWCNTs/ SiO2 and Nano...magnetization measurements -1.5 0.0 1.5 To rq ue (a .u .) IP H = 1.9 T CoFe2 on glass in-Field -1.5 0.0 1.5 To rq ue (a . u .) 360300240180120600 Field Angle...deg.) IP H = 1.9 T CoFe2 on glass no-Field a b Fig. 2.3: Torque magnetometry for CoFe2 layer deposited (a) in-field and (b) deposited with no

  19. Fusion Research in Ioffe Institute

    NASA Astrophysics Data System (ADS)

    Askinazi, L. G.; Afanasyev, V. I.; Altukhov, A. B.; Bakharev, N. N.; Belokurov, A. A.; Bulanin, V. V.; Bykov, A. S.; Chernyshev, F. V.; Chugunov, I.; Dyachenko, V. V.; Esipov, L. A.; Gin, D.; Goncharov, P. R.; Gurchenko, A. D.; Gusakov, E. Z.; Gusev, V. K.; Heuraux, S.; Iblyaminova, A. D.; Irzak, M. A.; Kantor, M. Yu.; Kaveeva, E. G.; Kiviniemi, T.; Khilkevitch, E. M.; Khitrov, S. A.; Khromov, N. A.; Kornev, V. A.; Kouprienko, D. V.; Kurskiev, G. S.; Lashkul, S. I.; Lebedev, S. V.; Leerink, S.; Melnik, A. D.; Minaev, V. B.; Mironov, M. I.; Miroshnikov, I. V.; Mukhin, E. E.; Nesenevich, V. G.; Niskala, P.; Novokhatsky, A. N.; Patrov, M. I.; Perevalov, A. A.; Petrov, M. P.; Petrov, A. V.; Petrov, Yu. V.; Popov, A. Yu.; Rozhansky, V. A.; Rozhdestvenskiy, V. V.; Sakharov, N. V.; Saveliev, A. N.; Senichenkov, I. Yu.; Sergeev, V. Yu.; Shchegolev, P. B.; Shatalin, S. V.; Shcherbinin, O. N.; Shevelev, A. E.; Sidorov, A. V.; da Silva, F.; Smirnov, A. I.; Stepanov, A. Yu.; Sysoeva, E. V.; Teplova, N. V.; Tolstyakov, S. Yu.; Tukachinsky, A. S.; Varfolomeev, V. I.; Vekshina, E. O.; Vildjunas, M. I.; Voronin, A. V.; Voskoboinikov, S. P.; Wagner, F.; Yashin, A. Yu.; Zhubr, N. A.

    2015-10-01

    In this paper we present the fusion related activities of the Plasma Physics Division at the Ioffe Institute. The first experiments on lower hybrid current drive (LHCD) in a spherical tokamak performed at the Globus-M tokamak (R = 0.36 m, a = 0.24 m, Bt = 0.4 T, Ip = 200 kA) with a novel poloidally oriented grill resulted in an RF driven current of up to 30 kA at (100 kW, 2.5 GHz), exceeding the modelling predictions. At the FT-2 tokamak (R = 0.56 m, a = 0.08 m, Bt = 3 T, Ip = 30 kA) experiments with a traditional toroidally oriented grill revealed no strong dependence of the LHCD density limit on the H/D ratio in spite of LH resonance densities differing by a factor of 3. Microwave Doppler reflectometry (DR) at the Globus-M, and DR and heavy ion beam probe measurements at the tokamak TUMAN-3M (R = 0.53 m, a = 0.24 m, Bt = 1.0 T, Ip = 190 kA) demonstrated geodesic acoustic mode (GAM) suppression at the L to H transition. Observations at FT-2 using Doppler Enhanced Scattering showed that the GAM amplitude is anti-correlated both spatially and temporally to the drift turbulence level and electron thermal diffusivity. For the first time turbulence amplitude modulation at the GAM frequency was found both experimentally and in global gyrokinetic modelling. A model of the L-H transition is proposed based on this effect. The loss mechanisms of energetic ions' (EI) were investigated in the neutral beam injection (NBI) experiments on Globus-M and TUMAN-3M. Empirical scaling of the 2.45 MeV DD neutron rate for the two devices shows a strong dependence on toroidal field Bt1.29 and plasma current Ip1.34 justifying the Bt and Ip increase by a factor of 2.5 for the proposed upgrade of Globus-M. Bursts of ˜1 MHz Alfvenic type oscillations correlating with sawtooth crashes were observed in ohmic TUMAN-3M discharges. The possibility of low threshold parametric excitation of Bernstein and upper hybrid waves trapped in drift-wave eddies resulting in anomalous absorption in electron cyclotron resonance heating (ECRH) experiments in toroidal plasmas was identified theoretically. A novel method of radial correlation Doppler reflectometry is shown to be capable of measuring the turbulence wave-number spectrum in realistic 2D geometry. On the progress in design and fabrication of three diagnostics for ITER developed in the Ioffe institute is reported: neutral particle analysis, divertor Thomson scattering and gamma spectroscopy.

  20. Survey of heating and current drive for K-DEMO

    NASA Astrophysics Data System (ADS)

    Mikkelsen, D. R.; Kessel, C. E.; Poli, F. M.; Bertelli, N.; Kim, K.

    2018-03-01

    We present calculations of heating and current drive by neutral injection and by electromagnetic waves in the ion cyclotron, helicon, lower hybrid, and electron cyclotron frequency ranges for the steady state burn conditions in a K-DEMO configuration with I_p=12.3 MA, a  =  2.1 m, R_o=6.8 m, B_o=7.4 T, \

  1. A Multimedia over IP Integrated System for Military Communications

    DTIC Science & Technology

    2006-12-01

    stressed how communications requirements raise dramatically now, either in quantity either in quality, in order to effectively improve sensor...admission control based on network resources availability. We will stress the role of SIT and the characteristic of the Gatekeeper to act as the...considered: • Telecommuting - Telecommuting is a broad term referring to corporate employees who interact electronically with corporate resources

  2. Studies on impact of electron cyclotron wave injection on the internal transport barriers in JT-60U weak shear plasmas

    NASA Astrophysics Data System (ADS)

    Ide, S.; Takenaga, H.; Isayama, A.; Sakamoto, Y.; Yoshida, M.; Gormezano, C.

    2007-11-01

    Impact of the electron cyclotron range of frequency wave (ECRF) on the internal transport barriers (ITBs) in a weak shear (WS) plasma has been investigated in JT-60U. The fundamental O-mode ECRF of 110 GHz injected obliquely (co-current drive) from the low field side is used. It is observed that the ion temperature (Ti) ITB in a WS plasma can be degraded by ECRF. It is clarified for the first time that the degradation depends increasingly on the EC power (PEC) but decreasingly on the plasma current (Ip). Moreover it is confirmed that ECRF affects the toroidal rotation (Vt) indirectly and results in the flattening of Vt(ρ) and therefore the radial electric field (Er) profiles regardless of the direction of the target Vt(ρ), peaking co or counter direction (relative to the Ip direction). Furthermore, it is recently found that Ti and Vt in the whole ITB region are affected with almost no delay from the EC onset even with off-axis EC deposition. These results indicate that EC injection unveiled a semi-global structure that characterizes Ti ITB in a WS plasma.

  3. Oral delivery of prolyl hydroxylase inhibitor: AKB-4924 promotes localized mucosal healing in a mouse model of colitis.

    PubMed

    Marks, Ellen; Goggins, Bridie J; Cardona, Jocelle; Cole, Siobhan; Minahan, Kyra; Mateer, Sean; Walker, Marjorie M; Shalwitz, Robert; Keely, Simon

    2015-02-01

    Pharmacological induction of hypoxia-inducible factor (HIF), a global transcriptional regulator of the hypoxic response, by prolyl hydroxylase inhibitors (PHDi) is protective in murine models of colitis, and epithelial cells are critical for the observed therapeutic efficacy. Because systemic HIF activation may lead to potentially negative off-target effects, we hypothesized that targeting epithelial HIF through oral delivery of PHDi would be sufficient to protect against colitis in a mouse model. Using a chemically induced trinitrobenzene sulfonic acid murine model of colitis, we compared the efficacy of oral and intraperitoneal (i.p.) delivery of the PHDi; AKB-4924 in preventing colitis, as measured by endoscopy, histology, barrier integrity, and immune profiling. Furthermore, we measured potential off-target effects, examining HIF and HIF target genes in the heart and kidney, as well as erythropoietin and hematocrit levels. Oral administration of AKB-4924 exhibited mucosal protection comparable i.p. dosing. Oral delivery of PHDi led to reduced colonic epithelial HIF stabilization compared with i.p. delivery, but this was still sufficient to induce transcription of downstream HIF targets. Furthermore, oral delivery of PHDi led to reduced stabilization of HIF and activation of HIF targets in extraintestinal organs. Oral delivery of PHDi therapies to this intestinal mucosa protects against colitis in animal models and represents a potential therapeutic strategy for inflammatory bowel disease, which also precludes unwanted extraintestinal effects.

  4. Hydrothermal system of the Papandayan Volcano from temperature, self-potential (SP) and geochemical measurements

    NASA Astrophysics Data System (ADS)

    Byrdina, Svetlana; Revil, André; Gunawan, Hendra; Saing, Ugan B.; Grandis, Hendra

    2017-07-01

    Papandayan volcano in West Java, Indonesia, is characterized by intense hydrothermal activities manifested by numerous fumaroles at three craters or kawah, i.e. Mas, Manuk and Baru. The latter was created after November 2002 phreatic eruption. Since 2011, numerous volcano-tectonic B events are encountered and the volcano was set on alert status on several occasions. The purpose of the present study is to delineate the structure of the summital hydrothermal system from Self-Potential (SP), soil temperature and gas concentrations in the soil (CO2, SO2 and H2S) data. This combination of geophysical and geochemical methods allows identification of the weak permeable zones serving as preferential pathways for hydrothermal circulation and potential candidates to future landslides or flank collapses. This study is an on-going collaborative research project and we plan to conduct electrical resistivity tomography (ERT) and also Induced-Polarization (IP) surveys. Additional data would allow the 3D imaging of the studied area. The IP parameters will be used to characterise and to quantify the degree of alteration of the volcanic rocks as has been shown very recently in the laboratory studies. There are also rocks and soil samples that will undergo laboratory analyses at ISTerre for IP and complex resistivity parameters at the sample scale that will help to interpret the survey results.

  5. A data transmission method for particle physics experiments based on Ethernet physical layer

    NASA Astrophysics Data System (ADS)

    Huang, Xi-Ru; Cao, Ping; Zheng, Jia-Jun

    2015-11-01

    Due to its advantages of universality, flexibility and high performance, fast Ethernet is widely used in readout system design for modern particle physics experiments. However, Ethernet is usually used together with the TCP/IP protocol stack, which makes it difficult to implement readout systems because designers have to use the operating system to process this protocol. Furthermore, TCP/IP degrades the transmission efficiency and real-time performance. To maximize the performance of Ethernet in physics experiment applications, a data readout method based on the physical layer (PHY) is proposed. In this method, TCP/IP is replaced with a customized and simple protocol, which makes it easier to implement. On each readout module, data from the front-end electronics is first fed into an FPGA for protocol processing and then sent out to a PHY chip controlled by this FPGA for transmission. This kind of data path is fully implemented by hardware. From the side of the data acquisition system (DAQ), however, the absence of a standard protocol causes problems for the network related applications. To solve this problem, in the operating system kernel space, data received by the network interface card is redirected from the traditional flow to a specified memory space by a customized program. This memory space can easily be accessed by applications in user space. For the purpose of verification, a prototype system has been designed and implemented. Preliminary test results show that this method can meet the requirements of data transmission from the readout module to the DAQ with an efficient and simple manner. Supported by National Natural Science Foundation of China (11005107) and Independent Projects of State Key Laboratory of Particle Detection and Electronics (201301)

  6. Alternative Oxidase Transcription Factors AOD2 and AOD5 of Neurospora crassa Control the Expression of Genes Involved in Energy Production and Metabolism.

    PubMed

    Qi, Zhigang; Smith, Kristina M; Bredeweg, Erin L; Bosnjak, Natasa; Freitag, Michael; Nargang, Frank E

    2017-02-09

    In Neurospora crassa , blocking the function of the standard mitochondrial electron transport chain results in the induction of an alternative oxidase (AOX). AOX transfers electrons directly from ubiquinol to molecular oxygen. AOX serves as a model of retrograde regulation since it is encoded by a nuclear gene that is regulated in response to signals from mitochondria. The N. crassa transcription factors AOD2 and AOD5 are necessary for the expression of the AOX gene. To gain insight into the mechanism by which these factors function, and to determine if they have roles in the expression of additional genes in N. crassa , we constructed strains expressing only tagged versions of the proteins. Cell fractionation experiments showed that both proteins are localized to the nucleus under both AOX inducing and noninducing conditions. Furthermore, chromatin immunoprecipitation and high throughput sequencing (ChIP-seq) analysis revealed that the proteins are bound to the promoter region of the AOX gene under both conditions. ChIP-seq also showed that the transcription factors bind to the upstream regions of a number of genes that are involved in energy production and metabolism. Dependence on AOD2 and AOD5 for the expression of several of these genes was verified by quantitative PCR. The majority of ChIP-seq peaks observed were enriched for both AOD2 and AOD5. However, we also observed occasional sites where one factor appeared to bind preferentially. The most striking of these was a conserved sequence that bound large amounts of AOD2 but little AOD5. This sequence was found within a 310 bp repeat unit that occurs at several locations in the genome. Copyright © 2017 Qi et al.

  7. Metal Interactions at the Biochar-Water Interface: Energetics and Structure-Sorption Relationships Elucidated by Flow Adsorption Microcalorimetry

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

    Harvey, Omar R.; Herbert, Bruce; Rhue, Roy D.

    2011-06-01

    Interest in biochars and their role in the biogeochemical cycling of metals have increased in recent years. However, a systematic understanding of the mechanisms involved in biochar-metal interactions and conditions under which a given mechanism is predominant is still needed. We used flow adsorption micro-calorimetry to study structure-sorption relationships between twelve plant-derived biochars and two metals of different ionization potential (Ip). Biochar structure influenced the amount of K+ (Ip = 419 kJ mol-1) or Cd(II) (Ip = 868 kJ mol-17 ) sorption but had no effect on the mechanism of sorption. Irrespective of the biochar, K+ sorption was exothermic, surface-controlledmore » and occurred via an ion-exchange mechanism on negatively- charged sites with molar heats of adsorption (_Hads) of -4 kJ mol-1 on wood versus -8 kJ mol-1 on grass biochars. In contrast, Cd(II) sorption was endothermic and favored surface complexation on uncharged biochar surfaces with _Hads of around +17 kJ mol-1. Cadmium sorption transitioned from surface- to diffusion-controlled on biochars formed at ≥ 350 oC and _Hads for Cd(II) sorption was the same on grass and wood biochars. We concluded that, in general, metals with lower Ip favor electrostatic interactions with biochars, while metals of higher Ip favor more covalent-like interactions.« less

  8. Genotoxicity of three food processing contaminants in transgenic mice expressing human sulfotransferases 1A1 and 1A2 as assessed by the in vivo alkaline single cell gel electrophoresis assay

    PubMed Central

    Høie, Anja Hortemo; Svendsen, Camilla; Brunborg, Gunnar; Glatt, Hansruedi; Alexander, Jan; Meinl, Walter

    2015-01-01

    The food processing contaminants 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP), 5‐hydroxymethylfurfural (HMF) and 2,5 dimethylfuran (DMF) are potentially both mutagenic and carcinogenic in vitro and/or in vivo, although data on DMF is lacking. The PHIP metabolite N‐hydroxy‐PhIP and HMF are bioactivated by sulfotransferases (SULTs). The substrate specificity and tissue distribution of SULTs differs between species. A single oral dose of PhIP, HMF or DMF was administered to wild‐type (wt) mice and mice expressing human SULT1A1/1A2 (hSULT mice). DNA damage was studied using the in vivo alkaline single cell gel electrophoresis (SCGE) assay. No effects were detected in wt mice. In the hSULT mice, PhIP and HMF exposure increased the levels of DNA damage in the liver and kidney, respectively. DMF was not found to be genotoxic. The observation of increased DNA damage in hSULT mice compared with wt mice supports the role of human SULTs in the bioactivation of N‐hydroxy‐PhIP and HMF in vivo. Environ. Mol. Mutagen. 56:709–714, 2015. © 2015 The Authors. Environmental and Molecular Mutagenesis Published by Wiley Periodicals, Inc. PMID:26270892

  9. Celastrol attenuates inflammatory and neuropathic pain mediated by cannabinoid receptor type 2.

    PubMed

    Yang, Longhe; Li, Yanting; Ren, Jie; Zhu, Chenggang; Fu, Jin; Lin, Donghai; Qiu, Yan

    2014-08-06

    Celastrol, a major active ingredient of Chinese herb Tripterygium wilfordii Hook. f. (thunder god vine), has exhibited a broad spectrum of pharmacological activities, including anti-inflammation, anti-cancer and immunosuppression. In the present study, we used animal models of inflammatory pain and neuropathic pain, generated by carrageenan injection and spared nerve injury (SNI), respectively, to evaluate the effect of celastrol and to address the mechanisms underlying pain processing. Intraperitoneal (i.p.) injection of celastrol produced a dose-dependent inhibition of carrageenan-induced edema and allodynia. Real-time PCR analysis showed that celastrol (0.3 mg/kg, i.p.) significantly reduced mRNA expressions of inflammatory cytokines, TNF-α, IL-6, IL-1β, in carrageenan-injected mice. In SNI mice, pain behavior studies showed that celastrol (1 mg/kg, i.p.) effectively prevented the hypersensitivity of mechanical nociceptive response on the third day post-surgery and the seventh day post-surgery. Furthermore, the anti-hyperalgesic effects of celastrol in carrageenan-injected mice and SNI mice were reversed by SR144528 (1 mg/kg, i.p.), a specific cannabinoid receptor-2 (CB2) receptor antagonist, but not by SR141716 (1 mg/kg, i.p.), a specific cannabinoid receptor-1 (CB1) receptor antagonist. Taken together, our results demonstrate the analgesia effects of celastrol through CB2 signaling and propose the potential of exploiting celastrol as a novel candidate for pain relief.

  10. Intoxication by Intraperitoneal Injection or Oral Gavage Equally Potentiates Postburn Organ Damage and Inflammation

    PubMed Central

    Chen, Michael M.; Palmer, Jessica L.; Ippolito, Jill A.; Curtis, Brenda J.; Choudhry, Mashkoor A.; Kovacs, Elizabeth J.

    2013-01-01

    The increasing prevalence of binge drinking and its association with trauma necessitate accurate animal models to examine the impact of intoxication on the response and outcome to injuries such as burn. While much research has focused on the effect of alcohol dose and duration on the subsequent inflammatory parameters following burn, little evidence exists on the effect of the route of alcohol administration. We examined the degree to which intoxication before burn injury causes systemic inflammation when ethanol is given by intraperitoneal (i.p.) injection or oral gavage. We found that intoxication potentiates postburn damage in the ileum, liver, and lungs of mice to an equivalent extent when either ethanol administration route is used. We also found a similar hematologic response and levels of circulating interleukin-6 (IL-6) when either ethanol paradigm achieved intoxication before burn. Furthermore, both i.p. and gavage resulted in similar blood alcohol concentrations at all time points tested. Overall, our data show an equal inflammatory response to burn injury when intoxication is achieved by either i.p. injection or oral gavage, suggesting that findings from studies using either ethanol paradigm are directly comparable. PMID:24379525

  11. Innovative polymeric system (IPS) for solvent-free lipophilic drug transdermal delivery via dissolving microneedles.

    PubMed

    Dangol, Manita; Yang, Huisuk; Li, Cheng Guo; Lahiji, Shayan Fakhraei; Kim, Suyong; Ma, Yonghao; Jung, Hyungil

    2016-02-10

    Lipophilic drugs are potential drug candidates during drug development. However, due to the need for hazardous organic solvents for their solubilization, these drugs often fail to reach the pharmaceutical market, and in doing so highlight the importance of solvent free systems. Although transdermal drug delivery systems (TDDSs) are considered prospective safe drug delivery routes, a system involving lipophilic drugs in solvent free or powder form has not yet been described. Here, we report, for the first time, a novel approach for the delivery of every kind of lipophilic drug in powder form based on an innovative polymeric system (IPS). The phase transition of powder form of lipophilic drugs due to interior chemical bonds between drugs and biodegradable polymers and formation of nano-sized colloidal structures allowed the fabrication of dissolving microneedles (DMNs) to generate a powerful TDDS. We showed that IPS based DMN with powder capsaicin enhances the therapeutic effect for treatment of the rheumatic arthritis in a DBA/1 mouse model compared to a solvent-based system, indicating the promising potential of this new solvent-free platform for lipophilic drug delivery. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. A novel double gate MOSFET by symmetrical insulator packets with improved short channel effects

    NASA Astrophysics Data System (ADS)

    Ramezani, Zeinab; Orouji, Ali A.

    2018-03-01

    In this article, we study a novel double-gate SOI MOSFET structure incorporating insulator packets (IPs) at the junction between channel and source/drain (S/D) ends. The proposed MOSFET has great strength in inhibiting short channel effects and OFF-state current that are the main problems compared with conventional one due to the significant suppressed penetrations of both the lateral electric field and the carrier diffusion from the S/D into the channel. Improvement of the hot electron reliability, the ON to OFF drain current ratio, drain-induced barrier lowering, gate-induced drain leakage and threshold voltage over conventional double-gate SOI MOSFETs, i.e. without IPs, is displayed with the simulation results. This study is believed to improve the CMOS device reliability and is suitable for the low-power very-large-scale integration circuits.

  13. Promoting global health: utilizing WHO to integrate public health, innovation and intellectual property.

    PubMed

    Mackey, Tim K; Liang, Bryan A

    2012-12-01

    The appropriate role of innovation and intellectual property (IP) in global public health is a controversial issue. Discussion is one-sided, with potential benefits advocated by industry in stark contrast to condemnation by certain civil society players. WHO's Public Health, Innovation and Intellectual Property Department (PHI) was established to address healthcare resource need for developing countries, assess impact of innovation and IP on access to medicines, explore innovative funding mechanisms for R&D and provide evidence-based policy-making recommendations in response to the changing global health landscape. Importantly, PHI could represent a potential forum to bridge shared, yet often diverse, interests and opportunities between various public and private stakeholders, a crucial issue for ensuring the future viability of WHO. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Higher-order equation-of-motion coupled-cluster methods for ionization processes.

    PubMed

    Kamiya, Muneaki; Hirata, So

    2006-08-21

    Compact algebraic equations defining the equation-of-motion coupled-cluster (EOM-CC) methods for ionization potentials (IP-EOM-CC) have been derived and computer implemented by virtue of a symbolic algebra system largely automating these processes. Models with connected cluster excitation operators truncated after double, triple, or quadruple level and with linear ionization operators truncated after two-hole-one-particle (2h1p), three-hole-two-particle (3h2p), or four-hole-three-particle (4h3p) level (abbreviated as IP-EOM-CCSD, CCSDT, and CCSDTQ, respectively) have been realized into parallel algorithms taking advantage of spin, spatial, and permutation symmetries with optimal size dependence of the computational costs. They are based on spin-orbital formalisms and can describe both alpha and beta ionizations from open-shell (doublet, triplet, etc.) reference states into ionized states with various spin magnetic quantum numbers. The application of these methods to Koopmans and satellite ionizations of N2 and CO (with the ambiguity due to finite basis sets eliminated by extrapolation) has shown that IP-EOM-CCSD frequently accounts for orbital relaxation inadequately and displays errors exceeding a couple of eV. However, these errors can be systematically reduced to tenths or even hundredths of an eV by IP-EOM-CCSDT or CCSDTQ. Comparison of spectroscopic parameters of the FH+ and NH+ radicals between IP-EOM-CC and experiments has also underscored the importance of higher-order IP-EOM-CC treatments. For instance, the harmonic frequencies of the A 2Sigma- state of NH+ are predicted to be 1285, 1723, and 1705 cm(-1) by IP-EOM-CCSD, CCSDT, and CCSDTQ, respectively, as compared to the observed value of 1707 cm(-1). The small adiabatic energy separation (observed 0.04 eV) between the X 2Pi and a 4Sigma- states of NH+ also requires IP-EOM-CCSDTQ for a quantitative prediction (0.06 eV) when the a 4Sigma- state has the low-spin magnetic quantum number (s(z) = 1/2). When the state with s(z) = 3/2 is sought, the energy separations converge much more rapidly with the IP-EOM-CCSD value (0.03 eV) already being close to the observed (0.04 eV).

  15. Mini-dystrophin Expression Down-regulates IP3-mediated Calcium Release Events in Resting Dystrophin-deficient Muscle Cells

    PubMed Central

    Balghi, Haouaria; Sebille, Stéphane; Mondin, Ludivine; Cantereau, Anne; Constantin, Bruno; Raymond, Guy; Cognard, Christian

    2006-01-01

    We present here evidence for the enhancement, at rest, of an inositol 1,4,5-trisphosphate (IP3)–mediated calcium signaling pathway in myotubes from dystrophin-deficient cell lines (SolC1(−)) as compared to a cell line from the same origin but transfected with mini-dystrophin (SolD(+)). With confocal microscopy, the number of sites discharging calcium (release site density [RSD]) was quantified and found more elevated in SolC1(−) than in SolD(+) myotubes. Variations of membrane potential had no significant effect on this difference, and higher resting [Ca2+]i in SolC1(−) (Marchand, E., B. Constantin, H. Balghi, M.C. Claudepierre, A. Cantereau, C. Magaud, A. Mouzou, G. Raymond, S. Braun, and C. Cognard. 2004. Exp. Cell Res. 297:363–379) cannot explain alone higher RSD. The exposure with SR Ca2+ channel inhibitors (ryanodine and 2-APB) and phospholipase C inhibitor (U73122) significantly reduced RSD in both cell types but with a stronger effect in dystrophin-deficient SolC1(−) myotubes. Immunocytochemistry allowed us to localize ryanodine receptors (RyRs) as well as IP3 receptors (IP3Rs), IP3R-1 and IP3R-2 isoforms, indicating the presence of both RyRs-dependent and IP3-dependent release systems in both cells. We previously reported evidence for the enhancement, through a Gi protein, of the IP3-mediated calcium signaling pathway in SolC1(−) as compared to SolD(+) myotubes during a high K+ stimulation (Balghi, H., S. Sebille, B. Constantin, S. Patri, V. Thoreau, L. Mondin, E. Mok, A. Kitzis, G. Raymond, and C. Cognard. 2006. J. Gen. Physiol. 127:171–182). Here we show that, at rest, these regulation mechanisms are also involved in the modulation of calcium release activities. The enhancement of resting release activity may participate in the calcium overload observed in dystrophin-deficient myotubes, and our findings support the hypothesis of the regulatory role of mini-dystrophin on intracellular signaling. PMID:16847098

  16. Mini-dystrophin Expression Down-regulates Overactivation of G Protein–mediated IP3 Signaling Pathway in Dystrophin-deficient Muscle Cells

    PubMed Central

    Balghi, Haouaria; Sebille, Stéphane; Constantin, Bruno; Patri, Sylvie; Thoreau, Vincent; Mondin, Ludivine; Mok, Elise; Kitzis, Alain; Raymond, Guy; Cognard, Christian

    2006-01-01

    We present here evidence for the enhancement of an inositol 1,4,5-trisphosphate (IP3) mediated calcium signaling pathway in myotubes from dystrophin-deficient cell lines (SolC1(−)) as compared to a cell line from the same origin but transfected with mini-dystrophin (SolD(+)). With confocal microscopy, we demonstrated that calcium rise, induced by the perifusion of a solution containing a high potassium concentration, was higher in SolC1(−) than in SolD(+) myotubes. The analysis of amplitude and kinetics of the calcium increase in SolC1(−) and in SolD(+) myotubes during the exposure with SR Ca2+ channel inhibitors (ryanodine and 2-APB) suggested the presence of two mechanisms of SR calcium release: (1) a fast SR calcium release that depended on ryanodine receptors and (2) a slow SR calcium release mediated by IP3 receptors. Detection analyses of mRNAs (reverse transcriptase [RT]-PCR) and proteins (Western blot and immunolocalization) demonstrated the presence of the three known isoforms of IP3 receptors in both SolC1(−) and SolD(+) myotubes. Furthermore, analysis of the kinetics of the rise in calcium revealed that the slow IP3-dependent release may be increased in the SolC1(−) as compared to the SolD(+), suggesting an inhibitory effect of mini-dystrophin in this signaling pathway. Upon incubation with pertussis toxin (PTX), an inhibitory effect similar to that of the IP3R inhibitor (2-APB) was observed on K+-evoked calcium release. This result suggests the involvement of a Gi protein upstream of the IP3 pathway in these stimulation conditions. A hypothetical model is depicted in which both Gi protein and IP3 production could be involved in K+-evoked calcium release as well as a possible interaction with mini-dystrophin. Our findings demonstrate the existence of a potential relationship between mini-dystrophin and SR calcium release as well as a regulatory role of mini-dystrophin on intracellular signaling. PMID:16446505

  17. TRAF3IP2 mediates atherosclerotic plaque development and vulnerability in ApoE−/− mice

    PubMed Central

    Prasad, Sakamuri Siva Sankara Vara; Higashi, Yusuke; Sukhanov, Sergiy; Siddesha, Jalahalli M; Delafontaine, Patrice; Siebenlist, Ulrich; Chandrasekar, Bysani

    2016-01-01

    Background and aims Atherosclerosis is a major cause of heart attack and stroke. Inflammation plays a critical role in the development of atherosclerosis. Since the cytoplasmic adaptor molecule TRAF3IP2 (TRAF3-Interacting Protein 2) plays a causal role in various autoimmune and inflammatory diseases, we hypothesized that TRAF3IP2 mediates atherosclerotic plaque development. Methods TRAF3IP2/ApoE double knockout (DKO) mice were generated by crossing TRAF3IP2−/− and ApoE−/− mice. ApoE−/− mice served as controls. Both DKO and control mice were fed a high-fat diet for 12 weeks. Plasma lipids were measured by ELISA, atherosclerosis by en face analysis of aorta and plaque cross-section measurements at the aortic valve region, plaque necrotic core area, collagen and smooth muscle cell content by histomorphometry, and aortic gene expression by RT-qPCR. Results The plasma lipoprotein profile was not altered by TRAF3IP2 gene deletion in ApoE−/− mice. While total aortic plaque area was decreased in DKO female, but not male mice, the plaque necrotic area was significantly decreased in DKO mice of both genders. Plaque collagen and smooth muscle cell contents were increased significantly in both female and male DKO mice compared to respective controls. Aortic expression of proinflammatory cytokine (Tumor necrosis factor α, TNFα), chemokine (Chemokine (C-X-C motif) Ligand 1, CXCL1) and adhesion molecule (Vascular cell adhesion molecule 1, VCAM1; and Intercellular adhesion molecule 1, ICAM1) gene expression were decreased in both male and female DKO mice. In addition, the male DKO mice showed a markedly reduced expression of extracellular matrix (ECM)-related genes, including TIMP1 (Tissue inhibitor of metalloproteinase 1), RECK (Reversion-Inducing- Cysteine-Rich Protein with Kazal Motifs) and ADAM17 (A Disintegrin And Metalloproteinase 17). Conclusions TRAF3IP2 plays a causal role in atherosclerotic plaque development and vulnerability, possibly by inducing the expression of multiple proinflammatory mediators. TRAF3IP2 could be a potential therapeutic target in atherosclerotic vascular diseases. PMID:27237075

  18. Design, Realization, and First Validation of an Immersive Web-Based Virtual Patient Simulator for Training Clinical Decisions in Surgery.

    PubMed

    Kleinert, Robert; Heiermann, Nadine; Wahba, Roger; Chang, De-Huan; Hölscher, Arnulf H; Stippel, Dirk L

    2015-01-01

    Immersive patient simulators (IPS) allow an illusionary immersion into a synthetic world where the user can freely navigate through a 3-dimensional environment similar to computer games. Playful learning with IPS allows internalization of medical workflows without harming real patients. Ideally, IPS show high student acceptance and can have positive effect on knowledge gain. Development of IPS with high technical quality is resource intensive. Therefore most of the "high-fidelity" IPS are commercially driven. Usage of IPS in the daily curriculum is still rare. There is no academic-driven simulator that is freely accessible to every student and combines high immersion grade with a profound amount of medical content. Therefore it was our aim to develop an academic-driven IPS prototype that is free to use and combines a high immersion grade with profound medical content. In addition, a first validation of the prototype was conducted. The conceptual design included definition of the following parameters: amount of curricular content, grade of technical quality, availability, and level of validation. A preliminary validation was done with 25 students. Students' opinion about acceptance was evaluated by a Likert-scale questionnaire. Effect on knowledge gain was determined by testing concordance and predictive validity. A custom-made simulator prototype (Artificial learning interface for clinical education [ALICE]) displays a virtual clinic environment that can be explored from a first-person view similar to a video game. By controlling an avatar, the user navigates through the environment, is able to treat virtual patients, and faces the consequence of different decisions. ALICE showed high students' acceptance. There was positive correlation for concordance validity and predictive validity. Simulator usage had positive effect on reproduction of trained content and declarative knowledge. We successfully developed a university-based, IPS prototype (ALICE) with profound medical content. ALICE is a nonprofit simulator, easy to use, and showed high students' acceptance; thus it potentially provides an additional tool for supporting student teaching in the daily clinical curriculum. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  19. Exact solutions for a type of electron pairing model with spin-orbit interactions and Zeeman coupling.

    PubMed

    Liu, Jia; Han, Qiang; Shao, L B; Wang, Z D

    2011-07-08

    A type of electron pairing model with spin-orbit interactions or Zeeman coupling is solved exactly in the framework of the Richardson ansatz. Based on the exact solutions for the case with spin-orbit interactions, it is shown rigorously that the pairing symmetry is of the p + ip wave and the ground state possesses time-reversal symmetry, regardless of the strength of the pairing interaction. Intriguingly, how Majorana fermions can emerge in the system is also elaborated. Exact results are illustrated for two systems, respectively, with spin-orbit interactions and Zeeman coupling.

  20. Evaluation of insecticides for protecting Southwestern ponderosa pines from attack by engraver beetles (Coleoptera: Curculionidae: Scolytinae).

    PubMed

    DeGomez, Tom E; Hayes, Christopher J; Anhold, John A; McMillin, Joel D; Clancy, Karen M; Bosu, Paul P

    2006-04-01

    Insecticides that might protect pine trees from attack by engraver beetles (Ips spp.) have not been rigorously tested in the southwestern United States. We conducted two field experiments to evaluate the efficacy of several currently and potentially labeled preventative insecticides for protecting high-value ponderosa pine, Pinus ponderosa Dougl ex. Laws., from attack by engraver beetles. Preventative sprays (0.19% permethrin [Permethrin Plus C]; 0.03, 0.06, and 0.12% bifenthrin [Onyx]; and 1.0 and 2.0% carbaryl [Sevin SL] formulations) and systemic implants (0.875 g per capsule acephate [Acecap] and 0.650 g per capsule dinotefuran) were assessed on bolts (sections of logs) as a surrogate for live trees for a period of 13 mo posttreatment. The pine engraver, Ips pini (Say), was the most common bark beetle found attacking control and treated bolts, but sixspined ips, Ips calligraphus (Germar), and Ips lecontei Swain also were present. After approximately 13 mo posttreatment in one experiment, the spray treatments with 2.0% carbaryl, 0.19% permethrin, and 0.06 or 0.12% bifenthrin prevented Ips attack on the bolts at a protection level of > or = 70%. The acephate and dinotefuran systemic insecticides, and the 0.03% bifenthrin spray, provided inadequate (< or = 36%) protection in this experiment. For the other experiment, sprayed applications of 1.0% carbaryl, 0.19% permethrin, and 0.06% bifenthrin prevented beetle attack at protection levels of > or = 90, > or = 80, and > or = 70%, respectively, when bolts were exposed to Ips beetle attack for approximately 9-15 wk posttreatment. The sprays with 0.19% permethrin and 0.06% bifenthrin also provided > or = 90% protection when bolts were exposed for approximately 15-54 wk posttreatment. We concluded that under the conditions tested, 1.0 and 2.0% carbaryl, 0.19% permethrin, and 0.06 and 0.12% binfenthrin were acceptable preventative treatments for protecting ponderosa pine from successful engraver beetle attack for one entire flight season in the U.S. Southwest.

  1. Podocalyxin Is a Glycoprotein Ligand of the Human Pluripotent Stem Cell-Specific Probe rBC2LCN

    PubMed Central

    Tateno, Hiroaki; Matsushima, Asako; Hiemori, Keiko; Onuma, Yasuko; Ito, Yuzuru; Hasehira, Kayo; Nishimura, Ken; Ohtaka, Manami; Takayasu, Satoko; Nakanishi, Mahito; Ikehara, Yuzuru; Nakanishi, Mio; Ohnuma, Kiyoshi; Chan, Techuan; Toyoda, Masashi; Akutsu, Hidenori; Umezawa, Akihiro; Asashima, Makoto

    2013-01-01

    In comprehensive glycome analysis with a high-density lectin microarray, we have previously shown that the recombinant N-terminal domain of the lectin BC2L-C from Burkholderia cenocepacia (rBC2LCN) binds exclusively to undifferentiated human induced pluripotent stem (iPS) cells and embryonic stem (ES) cells but not to differentiated somatic cells. Here we demonstrate that podocalyxin, a heavily glycosylated type 1 transmembrane protein, is a glycoprotein ligand of rBC2LCN on human iPS cells and ES cells. When analyzed by DNA microarray, podocalyxin was found to be highly expressed in both iPS cells and ES cells. Western and lectin blotting revealed that rBC2LCN binds to podocalyxin with a high molecular weight of more than 240 kDa in undifferentiated iPS cells of six different origins and four ES cell lines, but no binding was observed in either differentiated mouse feeder cells or somatic cells. The specific binding of rBC2LCN to podocalyxin prepared from a large set of iPS cells (138 types) and ES cells (15 types) was also confirmed using a high-throughput antibody-overlay lectin microarray. Alkaline digestion greatly reduced the binding of rBC2LCN to podocalyxin, indicating that the major glycan ligands of rBC2LCN are presented on O-glycans. Furthermore, rBC2LCN was found to exhibit significant affinity to a branched O-glycan comprising an H type 3 structure (Ka, 2.5 × 104 M−1) prepared from human 201B7 iPS cells, indicating that H type 3 is a most probable potential pluripotency marker. We conclude that podocalyxin is a glycoprotein ligand of rBC2LCN on human iPS cells and ES cells. PMID:23526252

  2. Generation of Healthy Mice from Gene-Corrected Disease-Specific Induced Pluripotent Stem Cells

    PubMed Central

    Rittelmeyer, Ina; Sharma, Amar Deep; Sgodda, Malte; Zaehres, Holm; Bleidißel, Martina; Greber, Boris; Gentile, Luca; Han, Dong Wook; Rudolph, Cornelia; Steinemann, Doris; Schambach, Axel; Ott, Michael; Schöler, Hans R.; Cantz, Tobias

    2011-01-01

    Using the murine model of tyrosinemia type 1 (fumarylacetoacetate hydrolase [FAH] deficiency; FAH −/− mice) as a paradigm for orphan disorders, such as hereditary metabolic liver diseases, we evaluated fibroblast-derived FAH −/−-induced pluripotent stem cells (iPS cells) as targets for gene correction in combination with the tetraploid embryo complementation method. First, after characterizing the FAH −/− iPS cell lines, we aggregated FAH −/−-iPS cells with tetraploid embryos and obtained entirely FAH −/−-iPS cell–derived mice that were viable and exhibited the phenotype of the founding FAH −/− mice. Then, we transduced FAH cDNA into the FAH −/−-iPS cells using a third-generation lentiviral vector to generate gene-corrected iPS cells. We could not detect any chromosomal alterations in these cells by high-resolution array CGH analysis, and after their aggregation with tetraploid embryos, we obtained fully iPS cell–derived healthy mice with an astonishing high efficiency for full-term development of up to 63.3%. The gene correction was validated functionally by the long-term survival and expansion of FAH-positive cells of these mice after withdrawal of the rescuing drug NTBC (2-(2-nitro-4-fluoromethylbenzoyl)-1,3-cyclohexanedione). Furthermore, our results demonstrate that both a liver-specific promoter (transthyretin, TTR)-driven FAH transgene and a strong viral promoter (from spleen focus-forming virus, SFFV)-driven FAH transgene rescued the FAH-deficiency phenotypes in the mice derived from the respective gene-corrected iPS cells. In conclusion, our data demonstrate that a lentiviral gene repair strategy does not abrogate the full pluripotent potential of fibroblast-derived iPS cells, and genetic manipulation of iPS cells in combination with tetraploid embryo aggregation provides a practical and rapid approach to evaluate the efficacy of gene correction of human diseases in mouse models. PMID:21765802

  3. Head-camera video recordings of trauma core competency procedures can evaluate surgical resident's technical performance as well as colocated evaluators.

    PubMed

    Mackenzie, Colin F; Pasley, Jason; Garofalo, Evan; Shackelford, Stacy; Chen, Hegang; Longinaker, Nyaradzo; Granite, Guinevere; Pugh, Kristy; Hagegeorge, George; Tisherman, Samuel A

    2017-07-01

    Unbiased evaluation of trauma core competency procedures is necessary to determine if residency and predeployment training courses are useful. We tested whether a previously validated individual procedure score (IPS) for individual procedure vascular exposure and fasciotomy (FAS) performance skills could discriminate training status by comparing IPS of evaluators colocated with surgeons to blind video evaluations. Performance of axillary artery (AA), brachial artery (BA), and femoral artery (FA) vascular exposures and lower extremity FAS on fresh cadavers by 40 PGY-2 to PGY-6 residents was video-recorded from head-mounted cameras. Two colocated trained evaluators assessed IPS before and after training. One surgeon in each pretraining tertile of IPS for each procedure was randomly identified for blind video review. The same 12 surgeons were video-recorded repeating the procedures less than 4 weeks after training. Five evaluators independently reviewed all 96 randomly arranged deidentified videos. Inter-rater reliability/consistency, intraclass correlation coefficients were compared by colocated versus video review of IPS, and errors. Study methodology and bias were judged by Medical Education Research Study Quality Instrument and the Quality Assessment of Diagnostic Accuracy Studies criteria. There were no differences (p ≥ 0.5) in IPS for AA, FA, FAS, whether evaluators were colocated or reviewed video recordings. Evaluator consistency was 0.29 (BA) - 0.77 (FA). Video and colocated evaluators were in total agreement (p = 1.0) for error recognition. Intraclass correlation coefficient was 0.73 to 0.92, dependent on procedure. Correlations video versus colocated evaluations were 0.5 to 0.9. Except for BA, blinded video evaluators discriminated (p < 0.002) whether procedures were performed before training versus after training. Study methodology by Medical Education Research Study Quality Instrument criteria scored 15.5/19, Quality Assessment of Diagnostic Accuracy Studies 2 showed low bias risk. Video evaluations of AA, FA, and FAS procedures with IPS are unbiased, valid, and have potential for formative assessments of competency. Prognostic study, level II.

  4. Antidepressant-like activity of anthocyanidins from Hibiscus rosa-sinensis flowers in tail suspension test and forced swim test

    PubMed Central

    Shewale, Pallavi B.; Patil, Rupali A.; Hiray, Yogesh A.

    2012-01-01

    Aim: Flowers of Hibiscus rosa-sinensis Linn (Malvaceae) popularly known as “China-rose flowers” contain flavonoids. Flavonoids have been found to have antidepressant activity. The aim of the present study is to evaluate the antidepressant activity of flavonoids in H. rosa-sinensis flowers with possible involvement of monoamines. Materials and Methods: Anti-depressant activity of methanol extract containing anthocyanins (MHR) (30 and 100 mg/kg) and anthocyanidins (AHR) (30 and 100 mg/ kg) of H. rosa-sinensis flowers were evaluated in mice using behavioral tests such as tail suspension test (TST) and forced swim test (FST). The mechanism of action involved in antidepressant activity was investigated by observing the effect of extract after pre-treatment with low dose haloperidol, prazosin and para-chlorophenylalanine (p-CPA). Results: Present study exhibited significant decrease in immobility time in TST and FST, similar to that of imipramine (10 mg/kg, i.p.) which served as a positive control. The extract significantly attenuated the duration of immobility induced by Haloperidol (50 μg/ kg, i.p., a classical D2-like dopamine receptor antagonist), Prazosin (62.5 μg/kg, i.p., an α1-adrenoceptor antagonist) and p-chlorophenylalanine (100 mg/kg, i.p., × 3 days; an inhibitor of serotonin synthesis) in both TST and FST. Conclusion: It can be concluded that MHR and AHR possess potential antidepressant activity (through dopaminergic, noradrenergic and serotonergic mechanisms) and has therapeutic potential in the treatment of CNS disorders and provides evidence at least at preclinical levels. PMID:23087504

  5. Olive (Olea europaea L.) leaf extract elicits antinociceptive activity, potentiates morphine analgesia and suppresses morphine hyperalgesia in rats.

    PubMed

    Esmaeili-Mahani, Saeed; Rezaeezadeh-Roukerd, Maryam; Esmaeilpour, Khadije; Abbasnejad, Mehdi; Rasoulian, Bahram; Sheibani, Vahid; Kaeidi, Ayat; Hajializadeh, Zahra

    2010-10-28

    Olive (Olea europaea) leaves are used as anti-rheumatic, anti-inflammatory, antinociceptive, antipyretic, vasodilatory, hypotensive, antidiuretic and hypoglycemic agents in traditional medicine. Recently, it has been shown that olive leaf extract (OLE) has calcium channel blocker property; however, its influences on nociceptive threshold and morphine effects have not yet been clarified. All experiments were carried out on male Wistar rats. The tail-flick, hot-plate and formalin tests were used to assess the effect of OLE on nociceptive threshold. To determine the effect of OLE on analgesic and hyperalgesic effects of morphine, OLE (6, 12 and 25 mg/kg i.p.) that had no significant nociceptive effect, was injected concomitant with morphine (5 mg/kg and 1 μg/kg i.p., respectively). The tail-flick test was used to assess the effect of OLE on anti- and pro-nociceptive effects of morphine. The data showed that OLE (50-200 mg/kg i.p.) could produce dose-dependent analgesic effect on tail-flick and hot-plate tests. Administration of 200 mg/kg OLE (i.p.) caused significant decrease in pain responses in the first and the second phases of formalin test. In addition, OLE could potentiate the antinociceptive effect of 5 mg/kg morphine and block low-dose morphine-induced hyperalgesia. Our results indicate that olive leaf extract has analgesic property in several models of pain and useful influence on morphine analgesia in rats. Therefore, it can be used for the treatment and/or management of painful conditions. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

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

    Gulec, Cagri, E-mail: cagri.gulec@gmail.com; Coban, Neslihan, E-mail: neslic@istanbul.edu.tr; Ozsait-Selcuk, Bilge, E-mail: ozsaitb@istanbul.edu.tr

    ROR-alpha is a nuclear receptor, activity of which can be modulated by natural or synthetic ligands. Due to its possible involvement in, and potential therapeutic target for atherosclerosis, we aimed to identify ROR-alpha target genes in monocytic and endothelial cell lines. We performed chromatin immunoprecipitation (ChIP) followed by tiling array (ChIP-on-chip) for ROR-alpha in monocytic cell line THP1 and endothelial cell line HUVEC. Following bioinformatic analysis of the array data, we tested four candidate genes in terms of dependence of their expression level on ligand-mediated ROR-alpha activity, and two of them in terms of promoter occupancy by ROR-alpha. Bioinformatic analysesmore » of ChIP-on-chip data suggested that ROR-alpha binds to genomic regions near the transcription start site (TSS) of more than 3000 genes in THP1 and HUVEC. Potential ROR-alpha target genes in both cell types seem to be involved mainly in membrane receptor activity, signal transduction and ion transport. While SPP1 and IKBKA were shown to be direct target genes of ROR-alpha in THP1 monocytes, inflammation related gene HMOX1 and heat shock protein gene HSPA8 were shown to be potential target genes of ROR-alpha. Our results suggest that ROR-alpha may regulate signaling receptor activity, and transmembrane transport activity through its potential target genes. ROR-alpha seems also to play role in cellular sensitivity to environmental substances like arsenite and chloroprene. Although, the expression analyses have shown that synthetic ROR-alpha ligands can modulate some of potential ROR-alpha target genes, functional significance of ligand-dependent modulation of gene expression needs to be confirmed with further analyses.« less

  7. Practical Integration-Free Episomal Methods for Generating Human Induced Pluripotent Stem Cells.

    PubMed

    Kime, Cody; Rand, Tim A; Ivey, Kathryn N; Srivastava, Deepak; Yamanaka, Shinya; Tomoda, Kiichiro

    2015-10-06

    The advent of induced pluripotent stem (iPS) cell technology has revolutionized biomedicine and basic research by yielding cells with embryonic stem (ES) cell-like properties. The use of iPS-derived cells for cell-based therapies and modeling of human disease holds great potential. While the initial description of iPS cells involved overexpression of four transcription factors via viral vectors that integrated within genomic DNA, advances in recent years by our group and others have led to safer and higher quality iPS cells with greater efficiency. Here, we describe commonly practiced methods for non-integrating induced pluripotent stem cell generation using nucleofection of episomal reprogramming plasmids. These methods are adapted from recent studies that demonstrate increased hiPS cell reprogramming efficacy with the application of three powerful episomal hiPS cell reprogramming factor vectors and the inclusion of an accessory vector expressing EBNA1. Copyright © 2015 John Wiley & Sons, Inc.

  8. A macro-economic framework for evaluation of cyber security risks related to protection of intellectual property.

    PubMed

    Andrijcic, Eva; Horowitz, Barry

    2006-08-01

    The article is based on the premise that, from a macro-economic viewpoint, cyber attacks with long-lasting effects are the most economically significant, and as a result require more attention than attacks with short-lasting effects that have historically been more represented in literature. In particular, the article deals with evaluation of cyber security risks related to one type of attack with long-lasting effects, namely, theft of intellectual property (IP) by foreign perpetrators. An International Consequence Analysis Framework is presented to determine (1) the potential macro-economic consequences of cyber attacks that result in stolen IP from companies in the United States, and (2) the likely sources of such attacks. The framework presented focuses on IP theft that enables foreign companies to make economic gains that would have otherwise benefited the U.S. economy. Initial results are presented.

  9. Interprofessional teamwork among students in simulated codes: a quasi-experimental study.

    PubMed

    Garbee, Deborah D; Paige, John; Barrier, Kendra; Kozmenko, Valeriy; Kozmenko, Lyubov; Zamjahn, John; Bonanno, Laura; Cefalu, Jean

    2013-01-01

    The purpose of this study was to evaluate the efficacy of using crisis resource management (CRM) principles and high-fidelity human patient simulation (HFHPS) for interprofessional (IP) team training of students from undergraduate nursing, nurse anesthesia, medical, and respiratory therapy. IP education using simulation-based training has the potential to transform education by improving teamwork and communication and breaking down silos in education. This one-year study used a quasi-experimental design to evaluate students' acquisition and retention of teamwork and communication skills. A convenience sample consisted of 52 students in the fall semester, with 40 students returning in the spring. Mean scores increased after training, and skills were retained fairly well. Any loss was regained with repeat training in the spring. The results suggest that using CRM and HFHPS is an effective pedagogy for teaching communication and teamwork skills to IP student teams.

  10. Onset of carbon-carbon bonding in the Nb(5)C(y) (y = 0-6) clusters: a threshold photo-ionisation and density functional theory study.

    PubMed

    Dryza, Viktoras; Gascooke, Jason R; Buntine, Mark A; Metha, Gregory F

    2009-02-21

    We have used photo-ionisation efficiency spectroscopy to determine the ionisation potentials (IPs) of the niobium-carbide clusters, Nb(5)C(y) (y = 0-6). Of these clusters Nb(5)C(2) and Nb(5)C(3) exhibit the lowest IPs. Complementary density functional theory calculations have been performed to locate the lowest energy isomers for each cluster. By comparing the experimental IPs with those calculated for candidate isomers, the structures of the Nb(5)C(y) clusters observed in the experiment are inferred. For all these structures, the underlying Nb(5) cluster has either a "prolate" or "oblate" trigonal bipyramid geometry. Both Nb(5)C(5) and Nb(5)C(6) are shown to contain carbon-carbon bonding in the form of one and two molecular C(2) units, respectively.

  11. Effects of Shilajit on the development of tolerance to morphine in mice.

    PubMed

    Tiwari, P; Ramarao, P; Ghosal, S

    2001-03-01

    Effects of concomitant administration of Processed Shilajit (PS, 0.1 and 1 mg/kg, i.p.), in Swiss mice were evaluated on the development of tolerance to morphine induced analgesia in the hot plate test. Chronic administration of morphine (10 mg/kg, i.p., b.i.d.) to mice over a duration of 10 days resulted in the development of tolerance to the analgesic effect of morphine. Concomitant administration of PS with morphine, from day 6 to day 10, resulted in a significant inhibition of the development of tolerance to morphine (10 mg/kg, i.p.) induced analgesia. Processed Shilajit per se, in the doses used, did not elicit any significant analgesia in mice; nor did the chronic concomitant administration of Processed Shilajit alter the morphine-induced analgesia. These findings with Processed Shilajit indicate its potential as a prospective modifier of analgesic tolerance to morphine. Copyright 2001 John Wiley & Sons, Ltd.

  12. Subtype-selective regulation of IP(3) receptors by thimerosal via cysteine residues within the IP(3)-binding core and suppressor domain.

    PubMed

    Khan, Samir A; Rossi, Ana M; Riley, Andrew M; Potter, Barry V L; Taylor, Colin W

    2013-04-15

    IP(3)R (IP(3) [inositol 1,4,5-trisphosphate] receptors) and ryanodine receptors are the most widely expressed intracellular Ca(2+) channels and both are regulated by thiol reagents. In DT40 cells stably expressing single subtypes of mammalian IP(3)R, low concentrations of thimerosal (also known as thiomersal), which oxidizes thiols to form a thiomercurylethyl complex, increased the sensitivity of IP(3)-evoked Ca(2+) release via IP(3)R1 and IP(3)R2, but inhibited IP(3)R3. Activation of IP(3)R is initiated by IP(3) binding to the IBC (IP(3)-binding core; residues 224-604) and proceeds via re-arrangement of an interface between the IBC and SD (suppressor domain; residues 1-223). Thimerosal (100 μM) stimulated IP(3) binding to the isolated NT (N-terminal; residues 1-604) of IP(3)R1 and IP(3)R2, but not to that of IP(3)R3. Binding of a competitive antagonist (heparin) or partial agonist (dimeric-IP(3)) to NT1 was unaffected by thiomersal, suggesting that the effect of thimerosal is specifically related to IP(3)R activation. IP(3) binding to NT1 in which all cysteine residues were replaced by alanine was insensitive to thimerosal, so too were NT1 in which cysteine residues were replaced in either the SD or IBC. This demonstrates that thimerosal interacts directly with cysteine in both the SD and IBC. Chimaeric proteins in which the SD of the IP(3)R was replaced by the structurally related A domain of a ryanodine receptor were functional, but thimerosal inhibited both IP(3) binding to the chimaeric NT and IP(3)-evoked Ca(2+) release from the chimaeric IP(3)R. This is the first systematic analysis of the effects of a thiol reagent on each IP(3)R subtype. We conclude that thimerosal selectively sensitizes IP(3)R1 and IP(3)R2 to IP(3) by modifying cysteine residues within both the SD and IBC and thereby stabilizing an active conformation of the receptor.

  13. Polarization Studies for the eRHIC Electron Storage Ring

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

    Gianfelice-Wendt, Eliana; Tepikian, S.

    A hadron/lepton collider with polarized beams has been under consideration by the scientific community since some years, in the U.S. and Europe. Among the various proposals, those by JLAB and BNL with polarized electron and proton beams are currently under closer study in the U.S. Experimenters call for the simultaneous storage of electron bunches with both spin helicity. In the BNL based Ring-Ring design, electrons are stored at top energy in a ring to be accommodated in the existing RHIC tunnel. The transversely polarized electron beam is injected into the storage ring at variable energies, between 5 and 18 GeV.more » Polarization is brought into the longitudinal direction at the IP by a couple of spin rotators. In this paper results of first studies of the attainable beam polarization level and lifetime in the storage ring at 18 GeV are presented.« less

  14. Effects of generation time on spray aerosol transport and deposition in models of the mouth-throat geometry.

    PubMed

    Worth Longest, P; Hindle, Michael; Das Choudhuri, Suparna

    2009-06-01

    For most newly developed spray aerosol inhalers, the generation time is a potentially important variable that can be fully controlled. The objective of this study was to determine the effects of spray aerosol generation time on transport and deposition in a standard induction port (IP) and more realistic mouth-throat (MT) geometry. Capillary aerosol generation (CAG) was selected as a representative system in which spray momentum was expected to significantly impact deposition. Sectional and total depositions in the IP and MT geometries were assessed at a constant CAG flow rate of 25 mg/sec for aerosol generation times of 1, 2, and 4 sec using both in vitro experiments and a previously developed computational fluid dynamics (CFD) model. Both the in vitro and numerical results indicated that extending the generation time of the spray aerosol, delivered at a constant mass flow rate, significantly reduced deposition in the IP and more realistic MT geometry. Specifically, increasing the generation time of the CAG system from 1 to 4 sec reduced the deposition fraction in the IP and MT geometries by approximately 60 and 33%, respectively. Furthermore, the CFD predictions of deposition fraction were found to be in good agreement with the in vitro results for all times considered in both the IP and MT geometries. The numerical results indicated that the reduction in deposition fraction over time was associated with temporal dissipation of what was termed the spray aerosol "burst effect." Based on these results, increasing the spray aerosol generation time, at a constant mass flow rate, may be an effective strategy for reducing deposition in the standard IP and in more realistic MT geometries.

  15. Caffeine alleviates the deterioration of Ca2+ release mechanisms and fragmentation of in vitro aged mouse eggs

    PubMed Central

    Zhang, Nan; Wakai, Takuya; Fissore, Rafael. A.

    2011-01-01

    The developmental competence of mammalian eggs is compromised by postovulatory aging. We and others found that in these eggs the intracellular calcium ([Ca2+]i) responses required for egg activation and initiation of development are altered. Nevertheless, the mechanism(s) underlying this defective Ca2+ release is not well known. Here, we investigated if the function of IP3R1, the major Ca2+ release channel at fertilization, was undermined in in vitro aged mouse eggs. We found that in aged eggs IP3R1 displayed reduced function, as many of the changes acquired during maturation that enhance IP3R1 Ca2+ conductivity such as phosphorylation, receptor reorganization and increased Ca2+ store content ([Ca2+]ER) were lost with increasing postovulatory time. IP3R1 fragmentation, possibly associated with the activation of caspase-3, was also observed in these eggs. Many of these changes were prevented when the postovulatory aging of eggs was carried out in the presence of caffeine, which minimized the decline in IP3R1 function and maintained [Ca2+]ER content. Caffeine also maintained mitochondrial membrane potential as measured by JC-1 fluorescence. We therefore conclude that [Ca2+]i responses in aged eggs are undermined by reduced IP3R1 sensitivity, decreased [Ca2+]ER and compromised mitochondrial function, and that addition of caffeine ameliorates most of these aging-associated changes. Understanding the molecular basis of the protective effects of caffeine will be useful in elucidating, and possibly reversing, the signaling pathway(s) compromised by in vitro culture of eggs. PMID:22095868

  16. β Subunits Functionally Differentiate Human Kv4.3 Potassium Channel Splice Variants

    PubMed Central

    Abbott, Geoffrey W.

    2017-01-01

    The human ventricular cardiomyocyte transient outward K+ current (Ito) mediates the initial phase of myocyte repolarization and its disruption is implicated in Brugada Syndrome and heart failure (HF). Human cardiac Ito is generated primarily by two Kv4.3 splice variants (Kv4.3L and Kv4.3S, diverging only by a C-terminal, S6-proximal, 19-residue stretch unique to Kv4.3L), which are differentially remodeled in HF, but considered functionally alike at baseline. Kv4.3 is regulated in human heart by β subunits including KChIP2b and KCNEs, but their effects were previously assumed to be Kv4.3 isoform-independent. Here, this assumption was tested experimentally using two-electrode voltage-clamp analysis of human subunits co-expressed in Xenopus laevis oocytes. Unexpectedly, Kv4.3L-KChIP2b channels exhibited up to 8-fold lower current augmentation, 40% slower inactivation, and 5 mV-shifted steady-state inactivation compared to Kv4.3S-KChIP2b. A synthetic peptide mimicking the 19-residue stretch diminished these differences, reinforcing the importance of this segment in mediating Kv4.3 regulation by KChIP2b. KCNE subunits induced further functional divergence, including a 7-fold increase in Kv4.3S-KCNE4-KChIP2b current compared to Kv4.3L-KCNE4-KChIP2b. The discovery of β-subunit-dependent functional divergence in human Kv4.3 splice variants suggests a C-terminal signaling hub is crucial to governing β-subunit effects upon Kv4.3, and demonstrates the potential significance of differential Kv4.3 gene-splicing and β subunit expression in myocyte physiology and pathobiology. PMID:28228734

  17. β Subunits Functionally Differentiate Human Kv4.3 Potassium Channel Splice Variants.

    PubMed

    Abbott, Geoffrey W

    2017-01-01

    The human ventricular cardiomyocyte transient outward K + current ( I to ) mediates the initial phase of myocyte repolarization and its disruption is implicated in Brugada Syndrome and heart failure (HF). Human cardiac I to is generated primarily by two Kv4.3 splice variants (Kv4.3L and Kv4.3S, diverging only by a C-terminal, S6-proximal, 19-residue stretch unique to Kv4.3L), which are differentially remodeled in HF, but considered functionally alike at baseline. Kv4.3 is regulated in human heart by β subunits including KChIP2b and KCNEs, but their effects were previously assumed to be Kv4.3 isoform-independent. Here, this assumption was tested experimentally using two-electrode voltage-clamp analysis of human subunits co-expressed in Xenopus laevis oocytes. Unexpectedly, Kv4.3L-KChIP2b channels exhibited up to 8-fold lower current augmentation, 40% slower inactivation, and 5 mV-shifted steady-state inactivation compared to Kv4.3S-KChIP2b. A synthetic peptide mimicking the 19-residue stretch diminished these differences, reinforcing the importance of this segment in mediating Kv4.3 regulation by KChIP2b. KCNE subunits induced further functional divergence, including a 7-fold increase in Kv4.3S-KCNE4-KChIP2b current compared to Kv4.3L-KCNE4-KChIP2b. The discovery of β-subunit-dependent functional divergence in human Kv4.3 splice variants suggests a C-terminal signaling hub is crucial to governing β-subunit effects upon Kv4.3, and demonstrates the potential significance of differential Kv4.3 gene-splicing and β subunit expression in myocyte physiology and pathobiology.

  18. Interaction between non-psychotropic cannabinoids in marihuana: effect of cannabigerol (CBG) on the anti-nausea or anti-emetic effects of cannabidiol (CBD) in rats and shrews.

    PubMed

    Rock, Erin M; Goodwin, Jennifer M; Limebeer, Cheryl L; Breuer, Aviva; Pertwee, Roger G; Mechoulam, Raphael; Parker, Linda A

    2011-06-01

    The interaction between two non-psychotropic cannabinoids, cannabidiol (CBD) and cannabigerol (CBG), which have been reported to act as a 5-hydroxytryptamine 1A (5-HT(1A)) agonist and antagonist, respectively, was evaluated. To evaluate the potential of CBG to reverse the anti-nausea, anti-emetic effects of CBD. In experiment 1, rats were pre-treated with CBG (0.0, 1, 5, and 10 mg/kg, ip), 15 min prior to being treated with CBD (experiment 1a: VEH or 5 mg/kg, ip) or 8-OH-DPAT (experiment 1b: VEH or 0.01 mg/kg, ip). Thirty minutes later, all rats received a pairing of 0.1% saccharin solution and LiCl (20 ml/kg of 0.15 M, ip). Seventy-two hours later, the rats received a drug-free taste reactivity test with saccharin to evaluate the effects of the treatments on the establishment of conditioned gaping reactions (a model of nausea). As well, conditioned saccharin avoidance was measured. In experiment 2, Suncus murinus were injected with CBG (5 mg/kg, ip) or VEH 15 min prior to CBD (5 mg/kg) or VEH and 30 min later were injected with LiCl (60 ml/kg of 0.15 M, i.p.), and the number of vomiting episodes were measured. CBD (5 mg/kg) suppressed conditioned gaping in rats and vomiting in shrews, which were reversed by pre-treatment with all doses of CBG. CBG also prevented the anti-nausea effects of 8-OH-DPAT. Interactions between moderate doses of CBG and CBD may oppose one another at the 5-HT(1A) receptor in the regulation of nausea and vomiting.

  19. Combined DC resistivity and induced polarization (DC-IP) for mapping the internal composition of a mine waste rock pile in Nova Scotia, Canada

    NASA Astrophysics Data System (ADS)

    Power, Christopher; Tsourlos, Panagiotis; Ramasamy, Murugan; Nivorlis, Aristeidis; Mkandawire, Martin

    2018-03-01

    Mine waste rock piles (WRPs) can contain sulfidic minerals whose interaction with oxygen and water can generate acid mine drainage (AMD). Thus, WRPs can be a long-term source of environmental pollution. Since the generation of AMD and its release into the environment is dependent on the net volume and bulk composition of waste rock, effective characterization of WRPs is necessary for successful remedial design and monitoring. In this study, a combined DC resistivity and induced polarization (DC-IP) approach was employed to characterize an AMD-generating WRP in the Sydney Coalfield, Nova Scotia, Canada. Two-dimensional (2D) DC-IP imaging with 6 survey lines was performed to capture the full WRP landform. 2D DC results indicated a highly heterogeneous and moderately conductive waste rock underlain by a resistive bedrock containing numerous fractures. 2D IP (chargeability) results identified several highly-chargeable regions within the waste, with normalized chargeability delineating regions specific to waste mineralogy only. Three-dimensional (3D) DC-IP imaging, using 17 parallel lines on the plateau of the pile, was then used to focus on the composition of the waste rock. The full 3D inverted DC-IP distributions were used to identify coincident and continuous zones (isosurfaces) of low resistivity (<30 Ω-m) and high normalized chargeability (>0.4 mS/m) that were inferred as generated AMD (leachate) and stored AMD (sulfides), respectively. Integrated geological, hydrogeological and geochemical data increased confidence in the geoelectrical interpretations. Knowledge on the location of potentially more reactive waste material is extremely valuable for improved long-term AMD monitoring at the WRP.

  20. Impact of social challenges on gaining employment for veterans with posttraumatic stress disorder: an exploratory moderator analysis.

    PubMed

    Davis, Lori L; Pilkinton, Patricia; Poddar, Swati; Blansett, Catherine; Toscano, Richard; Parker, Pamela E

    2014-06-01

    To explore whether psychosocial challenges impact effects of vocational rehabilitation in Veterans with Posttraumatic Stress Disorder (PTSD). A post hoc exploratory analysis of possible moderators of treatment was conducted on outcomes from a randomized, controlled trial of Individual Placement and Support in Veterans with PTSD. When examining groups within each moderator, there was a greater IPS supportive employment benefit in gaining competitive employment for those with inadequate transportation (number needed to treat [NNT] = 1.5) and inadequate housing (NNT = 1.5) compared with the main finding of the pilot study (NNT = 2.07). Compared with the main finding of the pilot study, there was no greater advantage of IPS for those with adequate transportation (NNT = 2.4) or adequate housing (NNT = 2.4). Compared with the main finding in the pilot study, those without a family care burden had a greater benefit from IPS (NNT = 1.4) and those with family care burden had a reduced treatment effect (NNT = 3.3). These results are exploratory and are not intended to guide clinical decision-making, but rather offer a potentially useful strategy in the design of larger trials of IPS.

  1. Skull Base Inverted Papilloma: A Comprehensive Review

    PubMed Central

    Wassef, Shafik N.; Batra, Pete S.; Barnett, Samuel

    2012-01-01

    Skull base inverted papilloma (IP) is an unusual entity for many neurosurgeons. IP is renowned for its high rate of recurrence, its ability to cause local destruction, and its association with malignancy. This paper is a comprehensive review of the reports, studies, and reviews published in the current biomedical literature from 1947 to September 2010 and synthesize this information to focus on its potential invasion to the base of the skull and possible intradural extension. The objective is to familiarize the clinician with the different aspects of this unusual disease. The role of modern diagnostic tools in medical imaging in order to assess clearly the limits of the tumors and to enhance the efficiency and the safety in the choice of a surgical approach is pointed out. The treatment guidelines for IP have undergone a complex evolution that continues today. Radical excision of the tumour is technically difficult and often incomplete. Successful management of IP requires resection of the affected mucosa which could be achieved with open surgery, endoscopic, or combined approach. Radio and chemotherapy were used for certain indications. More optimally research would be a multicenter randomized trials with large size cohorts. PMID:23346418

  2. Altered plasma levels of chemokines in autism and their association with social behaviors.

    PubMed

    Shen, Yidong; Ou, JInajun; Liu, Mengmeng; Shi, Lijuan; Li, Yamin; Xiao, Lu; Dong, Huixi; Zhang, Fengyu; Xia, Kun; Zhao, Jingping

    2016-10-30

    Autism Spectrum Disorder (ASD) is a group of neurodevelopment disorders with an unclear etiology. Chemokines have been implicated in the etiology and pathogenesis of ASD. The current study investigated the plasma levels of seven chemokines (RANTES, Eotaxin, MIP-1 α, MIP-1 β, MCP-1, IP-10, and MIG) in 42 young autistic patients and 35 age-matched typically developing (TD) children. The study also tested the association between these chemokine levels and social behaviors, as measured by the Social Responsiveness Scale (SRS). Compared to the TD children, RANTES, MIP-1α, and MIP-1β were higher, while IP-10 and MIG were lower in the autistic patients, after correcting for multiple comparisons. Among these seven chemokines, MIP-1α, MIP-1β and IP-10 levels were found to be associated with social behaviors in all the participants. Moreover, MIP-1α and IP-10 were found to be independent predictors of social behaviors. The results of our study support the hypothesis that altered chemokine levels are involved in the pathophysiology of ASD and they indicate that chemokines plasma levels could be potential biomarkers for ASD. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. The UNITAID Patent Pool Initiative: Bringing Patents Together for the Common Good.

    PubMed

    Bermudez, Jorge; 't Hoen, Ellen

    2010-01-19

    Developing and delivering appropriate, affordable, well-adapted medicines for HIV/AIDS remains an urgent challenge: as first-line therapies fail, increasing numbers of people require costly second-line therapy; one-third of ARVs are not available in pediatric formulations; and certain key first- and second-line triple fixed-dose combinations do not exist or sufficient suppliers are lacking. UNITAID aims to help solve these problems through an innovative initiative for the collective management of intellectual property (IP) rights - a patent pool for HIV medicines. The idea behind a patent pool is that patent holders - companies, governments, researchers or universities - voluntarily offer, under certain conditions, the IP related to their inventions to the patent pool. Any company that wants to use the IP to produce or develop medicines can seek a license from the pool against the payment of royalties, and may then produce the medicines for use in developing countries (conditional upon meeting agreed quality standards). The patent pool will be a voluntary mechanism, meaning its success will largely depend on the willingness of pharmaceutical companies to participate and commit their IP to the pool. Generic producers must also be willing to cooperate. The pool has the potential to provide benefits to all.

  4. An In Vitro Expansion System for Generation of Human iPS Cell-Derived Hepatic Progenitor-Like Cells Exhibiting a Bipotent Differentiation Potential

    PubMed Central

    Yanagida, Ayaka; Ito, Keiichi; Chikada, Hiromi; Nakauchi, Hiromitsu; Kamiya, Akihide

    2013-01-01

    Hepatoblasts, hepatic stem/progenitor cells in liver development, have a high proliferative potential and the ability to differentiate into both hepatocytes and cholangiocytes. In regenerative medicine and drug screening for the treatment of severe liver diseases, human induced pluripotent stem (iPS) cell-derived mature functional hepatocytes are considered to be a potentially good cell source. However, induction of proliferation of these cells is difficult ex vivo. To circumvent this problem, we generated hepatic progenitor-like cells from human iPS cells using serial cytokine treatments in vitro. Highly proliferative hepatic progenitor-like cells were purified by fluorescence-activated cell sorting using antibodies against CD13 and CD133 that are known cell surface markers of hepatic stem/progenitor cells in fetal and adult mouse livers. When the purified CD13highCD133+ cells were cultured at a low density with feeder cells in the presence of suitable growth factors and signaling inhibitors (ALK inhibitor A-83-01 and ROCK inhibitor Y-27632), individual cells gave rise to relatively large colonies. These colonies consisted of two types of cells expressing hepatocytic marker genes (hepatocyte nuclear factor 4α and α-fetoprotein) and a cholangiocytic marker gene (cytokeratin 7), and continued to proliferate over long periods of time. In a spheroid formation assay, these cells were found to express genes required for mature liver function, such as cytochrome P450 enzymes, and secrete albumin. When these cells were cultured in a suitable extracellular matrix gel, they eventually formed a cholangiocytic cyst-like structure with epithelial polarity, suggesting that human iPS cell-derived hepatic progenitor-like cells have a bipotent differentiation ability. Collectively these data indicate that this novel procedure using an in vitro expansion system is useful for not only liver regeneration but also for the determination of molecular mechanisms that regulate liver development. PMID:23935837

  5. An in vitro expansion system for generation of human iPS cell-derived hepatic progenitor-like cells exhibiting a bipotent differentiation potential.

    PubMed

    Yanagida, Ayaka; Ito, Keiichi; Chikada, Hiromi; Nakauchi, Hiromitsu; Kamiya, Akihide

    2013-01-01

    Hepatoblasts, hepatic stem/progenitor cells in liver development, have a high proliferative potential and the ability to differentiate into both hepatocytes and cholangiocytes. In regenerative medicine and drug screening for the treatment of severe liver diseases, human induced pluripotent stem (iPS) cell-derived mature functional hepatocytes are considered to be a potentially good cell source. However, induction of proliferation of these cells is difficult ex vivo. To circumvent this problem, we generated hepatic progenitor-like cells from human iPS cells using serial cytokine treatments in vitro. Highly proliferative hepatic progenitor-like cells were purified by fluorescence-activated cell sorting using antibodies against CD13 and CD133 that are known cell surface markers of hepatic stem/progenitor cells in fetal and adult mouse livers. When the purified CD13(high)CD133(+) cells were cultured at a low density with feeder cells in the presence of suitable growth factors and signaling inhibitors (ALK inhibitor A-83-01 and ROCK inhibitor Y-27632), individual cells gave rise to relatively large colonies. These colonies consisted of two types of cells expressing hepatocytic marker genes (hepatocyte nuclear factor 4α and α-fetoprotein) and a cholangiocytic marker gene (cytokeratin 7), and continued to proliferate over long periods of time. In a spheroid formation assay, these cells were found to express genes required for mature liver function, such as cytochrome P450 enzymes, and secrete albumin. When these cells were cultured in a suitable extracellular matrix gel, they eventually formed a cholangiocytic cyst-like structure with epithelial polarity, suggesting that human iPS cell-derived hepatic progenitor-like cells have a bipotent differentiation ability. Collectively these data indicate that this novel procedure using an in vitro expansion system is useful for not only liver regeneration but also for the determination of molecular mechanisms that regulate liver development.

  6. The behavior of glass fibers in the rat following intraperitoneal injection.

    PubMed

    Collier, C G; Morris, K J; Launder, K A; Humphreys, J A; Morgan, A; Eastes, W; Townsend, S

    1994-12-01

    Potential carcinogenicity of fibers is believed to be determined by three factors: the dose, dimensions and durability of the fibers concerned. Currently there is considerable debate on the appropriateness of using results from intraperitoneal (i.p.) injection studies to predict the potential carcinogenicity of airborne fibers following inhalation. For ip results to have any significance to potential inhalation hazards, there should be some relation between the biopersistence, dose, and dose distribution of fibers in the serosal cavity and in the lung. Preliminary results on the durability of one experimental glass fiber in the peritoneal cavity suggest differences in dissolution when compared with durability in the lung. In the lung, the diameters of the long fibers (> 20 microns) were observed to decline at a rate consistent with their exposure to a neutral pH environment. The diameter of shorter fibers declined much more slowly, consistent with exposure to a more acidic environment such as is found in the phagolysosomes of alveolar macrophages. In the peritoneal cavity all fibers, regardless of length, dissolved at the same rate as short fibers in the lung. The effect of dose on the distribution of fibers in the peritoneal cavity was investigated using similar experimental glass fibers and compared with that of a powder made from ground fibers. For both materials at doses up to 1.5 mg, material was taken up by the peritoneal organs roughly in proportion to their surface area. This uptake was complete 1-2 days after injection. At higher doses, the majority of the material in excess of this 1.5 mg formed clumps of fibers (nodules) which were either free in the peritoneal cavity or loosely bound to peritoneal organs. These nodules displayed classic foreign body reactions with an associated granulomatous inflammatory response. The findings on both durability in the peritoneal cavity and the presence of two distinct populations of material following i.p. injection have implications for the justification of the use of i.p. injections to assess potential carcinogenicity of fibers following inhalation.

  7. Subtype-selective regulation of IP3 receptors by thimerosal via cysteine residues within the IP3-binding core and suppressor domain

    PubMed Central

    Khan, Samir A.; Rossi, Ana M.; Riley, Andrew M.; Potter, Barry V. L.; Taylor, Colin W.

    2013-01-01

    IP3R (IP3 [inositol 1,4,5-trisphosphate] receptors) and ryanodine receptors are the most widely expressed intracellular Ca2+ channels and both are regulated by thiol reagents. In DT40 cells stably expressing single subtypes of mammalian IP3R, low concentrations of thimerosal (also known as thiomersal), which oxidizes thiols to form a thiomercurylethyl complex, increased the sensitivity of IP3-evoked Ca2+ release via IP3R1 and IP3R2, but inhibited IP3R3. Activation of IP3R is initiated by IP3 binding to the IBC (IP3-binding core; residues 224–604) and proceeds via re-arrangement of an interface between the IBC and SD (suppressor domain; residues 1–223). Thimerosal (100 μM) stimulated IP3 binding to the isolated NT (N-terminal; residues 1–604) of IP3R1 and IP3R2, but not to that of IP3R3. Binding of a competitive antagonist (heparin) or partial agonist (dimeric-IP3) to NT1 was unaffected by thiomersal, suggesting that the effect of thimerosal is specifically related to IP3R activation. IP3 binding to NT1 in which all cysteine residues were replaced by alanine was insensitive to thimerosal, so too were NT1 in which cysteine residues were replaced in either the SD or IBC. This demonstrates that thimerosal interacts directly with cysteine in both the SD and IBC. Chimaeric proteins in which the SD of the IP3R was replaced by the structurally related A domain of a ryanodine receptor were functional, but thimerosal inhibited both IP3 binding to the chimaeric NT and IP3-evoked Ca2+ release from the chimaeric IP3R. This is the first systematic analysis of the effects of a thiol reagent on each IP3R subtype. We conclude that thimerosal selectively sensitizes IP3R1 and IP3R2 to IP3 by modifying cysteine residues within both the SD and IBC and thereby stabilizing an active conformation of the receptor. PMID:23282150

  8. GnRH signalling pathways and GnRH-induced homologous desensitization in a gonadotrope cell line (alphaT3-1).

    PubMed

    Poulin, B; Rich, N; Mas, J L; Kordon, C; Enjalbert, A; Drouva, S V

    1998-07-25

    Exposure of the gonadotrope cells to gonadotropin-releasing hormone (GnRH) reduces their responsiveness to a new GnRH stimulation (homologous desensitization). The time frame as well as the mechanisms underlying this phenomenon are yet unclear. We studied in a gonadotrope cell line (alphaT3-1) the effects of short as well as long term GnRH pretreatments on the GnRH-induced phospholipases-C (PLC), -A2 (PLA2) and -D (PLD) activities, by measuring the production of IP3, total inositol phosphates (IPs), arachidonic acid (AA) and phosphatidylethanol (PEt) respectively. We demonstrated that although rapid desensitization of GnRH-induced IP3 formation did not occur in these cells, persistent stimulation of cells with GnRH or its analogue resulted in a time-dependent attenuation of GnRH-elicited IPs formation. GnRH-induced IPs desensitization was potentiated after direct activation of PKC by the phorbol ester TPA, suggesting the involvement of distinct mechanisms in the uncoupling exerted by either GnRH or TPA on GnRH-stimulated PI hydrolysis. The levels of individual phosphoinositides remained unchanged under any desensitization condition applied. Interestingly, while the GnRH-induced PLA2 activity was rapidly desensitized (2.5 min) after GnRH pretreatments, the neuropeptide-evoked PLD activation was affected at later times, indicating an important time-dependent contribution of these enzymatic activities in the sequential events underlying the GnRH-induced homologous desensitization processes in the gonadotropes. Under GnRH desensitization conditions, TPA was still able to induce PLD activation and to further potentiate the GnRH-evoked PLD activity. AlphaT3-1 cells possess several PKC isoforms which, except PKCzeta, were differentially down-regulated by TPA (PKCalpha, betaII, delta, epsilon, eta) or GnRH (PKCbetaII, delta, epsilon, eta). In spite of the presence of PKC inhibitors or down-regulation of PKC isoforms by TPA, the desensitizing effect of the neuropeptide on GnRH-induced IPs, AA and PEt formation remained unchanged. In conclusion, in alphaT3-1 cells the GnRH-induced homologous desensitization affects the GnRH coupling with PLC, PLA2 and PLD by mechanism(s) which do not implicate TPA-sensitive PKC isoforms, but likely reflect time-dependent modification(s) on the activation processes of the enzymes.

  9. Inter-serotype comparison of polysaccharides produced by extracellular enzymes from Streptococcus mutans.

    PubMed

    Yakushiji, T; Inoue, M; Koga, T

    1984-04-15

    The biochemical and morphological characteristics of polysaccharides synthesized from sucrose by extracellular enzymes from D-glucose-grown Streptococcus mutans representing serotypes a-g were compared. The polysaccharides synthesized by the enzymes from serotypes a, d, and g formed visible aggregates and firmly adhered to glass surfaces, whereas those formed by the enzymes from serotypes b, c, e, and f floated homogeneously and were poorly adherent. The enzymes of serotypes a, d, and g produced large amounts of water-insoluble polysaccharides (IPs, D-glucans), and those of serotypes b, c, e, and f water-soluble polysaccharides (SPs, D-glucans and D- fructans ). As compared with the IPs of serotypes b, c, e, and f, the IPs of serotypes a, d, and g (a) contained a higher proportion of (1----3)-alpha-D-glucosidic linkages and alpha-D-(1----3,6) branch linkages; (b) showed higher susceptibility to (1----3)-alpha-D-glucanase (serotype a excepted) and lower (1----6)-alpha-D-glucanase sensitivity; (c) contained larger amounts of high-molecular-weight fractions; (d) showed higher intrinsic viscosities (serotype b excepted); and (e) had lower S. mutans cell-agglutination activities. On electron-microscope observation, the IPs of all serotypes showed two fibrillar components; a double-stranded fibril, with short, fluffy protrusions extending out of its periphery, and a fine, single-stranded fibril. Thus, the serotypes could be divided into two major groups: a, d, and g; and b, c, e, and f. No similar grouping of serotypes was indicated by the chemical and morphological properties of SPs.

  10. IPS Empress inlays and onlays after four years--a clinical study.

    PubMed

    Krämer, N; Frankenberger, R; Pelka, M; Petschelt, A

    1999-07-01

    Ceramic inlays are used as esthetic alternatives to amalgam and other metallic materials for the restoration of badly damaged teeth. However, only limited clinical data are available regarding adhesive inlays and onlays with proximal margins located in dentine. In a prospective, controlled clinical study, the performance of IPS Empress inlays and onlays with cuspal replacements and margins below the amelocemental junction was examined. Ninety-six IPS Empress fillings were placed in 34 patients by six clinicians. The restorations were luted with four different composite systems. The dentin bonding system Syntac Classic was used in addition to the acid-etch-technique. At baseline and after 6 months, one, two and four years after placement the restorations were assessed by two calibrated investigators using modified USPHS codes and criteria. A representative sample of the restorations was investigated by scanning electron microscopy to evaluate wear. Seven of the 96 restorations investigated had to be replaced (failure rate 7%; Kaplan-Meier). Four inlays had suffered cohesive bulk fractures and three teeth required endodontic treatment. After four years in clinical service, significant deterioration (Friedman 2-way Anova; p < 0.05) was found to have occurred in the marginal adaptation of the remaining restorations. Seventy-nine percent of the surviving restorations exhibited marginal deficiencies, independent of the luting composite. Neither the absence of enamel margins, nor cuspal replacement significantly affected the adhesion or marginal quality of the restorations. After four years, extensive IPS Empress inlays and onlays bonded with the dentin bonding system Syntac Classic were found to have a 7% failure rate with 79% of the remaining restorations having marginal deficiencies.

  11. Efficacy and safety of articaine versus lidocaine for irreversible pulpitis treatment: A systematic review and meta-analysis of randomised controlled trials.

    PubMed

    Su, Naichuan; Li, Chunjie; Wang, Hang; Shen, Jiefei; Liu, Wenjia; Kou, Liang

    2016-04-01

    The aim was to assess the efficacy and safety of articaine compared with lidocaine for irreversible pulpitis (IP) treatment. Databases were explored electronically and relevant journals as well as the references of the included studies were hand-searched for randomised clinical trials comparing the efficacy and safety of articaine with lidocaine in treatment of IP. Twenty studies were included, of which eight had low risk of bias, 10 had moderate risk of bias and two had high risk of bias. In comparison with 2% lidocaine with 1:100,000 epinephrine, 4% articaine with 1:100,000 epinephrine showed a higher success rate in anaesthesia of IP at either person (risk ratio (RR) 1.15; 95% confidence intervals (CI) 1.10 1.20; P < 0.00001) or tooth unit (RR 1.10; 95% CI 1.10 1.19, P < 0.00001), lower VAS scores during injection phase (mean difference (MD) -0.67; 95% CI -1.26 -0.08, P = 0.02) and treatment phase (MD -3.35; 95% CI -3.78 -2.91, P < 0.00001), shorter onset time of pulpal anaesthesia (MD -0.94; 95% CI -1.13 -0.74, P < 0.00001) and lower percentage of patients undergoing adverse events (RR 0.17; 95% CI 0.03 0.92, P = 0.04). Given the efficacy and safety of the two solutions, 4% articaine with 1:100,000 epinephrine was superior to 2% lidocaine with 1:100,000 epinephrine in dental treatments in IP. © 2016 Australian Society of Endodontology Inc.

  12. Tunneling Spectroscopy Studies of Epitaxial Graphene on Silicon Carbide(0001) and Its Interfaces

    NASA Astrophysics Data System (ADS)

    Sandin, Andreas Axel Tomas

    A two dimensional network of sp2 bonded carbon atoms is defined as graphene. This novel material possesses remarkable electronic properties due to its unique band structure at the vicinity of the Fermi energy. The toughest challenge to bring use of graphene electronic properties in device geometries is that graphene is exceptionally sensitive to its electrical environment for integration into macroscopic system of electrical contacts and substrates. One of the most promising substrates for graphene is the polar surfaces of SiC for the reason it can be grown epitaxially by sublimating Si from the top-most SiC atomic layers. In this work, the interfaces of graphene grown on the Si-terminated polar surface SiC(0001) is studied in UHV using scanning tunneling microscopy (STM), scanning tunneling spectroscopy (STS), low energy electron diffraction (LEED) and auger electron Spectroscopy (AES). STM is used image the graphene surface and interfaces with the capability of atomic resolution. LEED is used to study surface atomic reciprocal ordering and AES is used to determine surface atomic composition during the graphene formation. Interfacial layer (Buffer layer), Single layer graphene and bilayer graphene are identified electronically by means of probing the first member of the image potential derived state. This state is found by dZ/dV spectroscopy in the high energy unoccupied states and is exceptionally sensitive to electrostatic changes to the surface which is detected by energy shifts of image potential states (IPS). This sensitivity is utilized to probe the graphene screening of external electric fields by varying the electric field in the tunneling junction and addresses the fact that charged impurity scattering is likely to be crucial for epitaxial graphene on SiC(0001) when it comes to transport parameters. Shifts of IPS energy position has also been used verify work function changes for identification of several Sodium Intercalation structures of epitaxial graphene. STS, STM along with DFT calculations are used to determine the interface location of Sodium, SiC-bufferlayer or bufferlayer-graphene intercalation. In this thesis, STM, and STS are used to study the interactions of paramagnetic FePc molecules with epitaxial graphene. The molecules, FePc, is found to interact with the graphene substrate where STM images show substrate induced orientation of FePc densely packed square lattice structure. At sub-monolayer coverages, FePc form a molecular gas at room temperature suggesting a low diffusion barrier on the graphene lattice. The substrate interaction is probed by STS and show an abnormally low LUMO energy that suggest strong electronic coupling between graphene and FePc. DFT calculations support the experimental observations and predict a spin-dependent molecule-graphene hybridization close to the Fermi energy in unoccupied states. For majority spins, DFT demonstrates the Dirac cone splits and a delocalized hybrid state is found in the band gap. For minority spin the Dirac cone is intact with energy of Dirac point empty. In addition, a novel method of improving UHV graphene growth on SiC(0001) is presented. During growth the SiC surface is exposed to atomic hydrogen which allows selective etching of Si over Carbon. This result in more uniform non-thermal formation of the buffer layer with many fewer defects and thus leads to nearly pit-free and defect-free thermal graphene layers.

  13. Aeronautical Related Applications Using ATN and TCP/IP Research Report

    NASA Technical Reports Server (NTRS)

    Dhas, C.; Mulkerin, T.; Wargo, C.; Nielsen, R.; Gaughan, T.; Griner, James H., Jr. (Technical Monitor)

    2000-01-01

    The course for the future aeronautical communications architecture has been defined for more than 10 years and is known as the Aeronautical Telecommunication Network (ATN). However, the operational implementations of making use of the ATN remain 3-5 years away, and these implementations are still only in the early phases of long-range projects. Thus, it is an objective of this effort to consider what the potential outcome within the air transport industry may be, given the rapid growth in commercial-off-the-shelf (COTS) products, networks, and services that are based upon the Internet TCP/IP protocol suite.

  14. Digital interface of electronic transformers based on embedded system

    NASA Astrophysics Data System (ADS)

    Shang, Qiufeng; Qi, Yincheng

    2008-10-01

    Benefited from digital interface of electronic transformers, information sharing and system integration in substation can be realized. An embedded system-based digital output scheme of electronic transformers is proposed. The digital interface is designed with S3C44B0X 32bit RISC microprocessor as the hardware platform. The μCLinux operation system (OS) is transplanted on ARM7 (S3C44B0X). Applying Ethernet technology as the communication mode in the substation automation system is a new trend. The network interface chip RTL8019AS is adopted. Data transmission is realized through the in-line TCP/IP protocol of uClinux embedded OS. The application result and character analysis show that the design can meet the real-time and reliability requirements of IEC60044-7/8 electronic voltage/current instrument transformer standards.

  15. Medical homes versus individual practice in primary care: impact on health care expenditures.

    PubMed

    Perelman, Julian; Roch, Isabelle; Heymans, Isabelle; Moureaux, Catherine; Lagasse, Raphael; Annemans, Lieven; Closon, Marie-Christine

    2013-08-01

    The medical home (MH) model has prompted increasing attention given its potential to improve quality of care while reducing health expenditures. We compare overall and specific health care expenditures in Belgium, from the third-party payer perspective (compulsory social insurance), between patients treated at individual practices (IP) and at MHs. We compare the sociodemographic profile of MH and IP users. This is a retrospective study using public insurance claims data. Generalized linear models estimate the impact on health expenditures of being treated at a MH versus IP, controlling for individual, and area-based sociodemographic characteristics. The choice of primary care setting is modeled using logistic regressions. A random sample of 43,678 persons followed during the year 2004. Third-party payer expenditures for primary care, secondary care consultations, pharmaceuticals, laboratory tests, acute and long-term inpatient care. Overall third-party payer expenditures do not differ significantly between MH and IP users (€+27). Third-party payer primary care expenditures are higher for MH than for IP users (€+129), but this difference is offset by lower expenditures for secondary care consultations (€-11), drugs (€-40), laboratory tests (€-5) and acute and long-term inpatient care (€-53). MHs attract younger and more underprivileged populations. MHs induce a shift in expenditures from secondary care, drugs, and laboratory tests to primary care, while treating a less economically favored population. Combined with positive results regarding quality, MH structures are a promising way to tackle the challenges of primary care.

  16. Infiltrating T cells promote renal cell carcinoma (RCC) progression via altering the estrogen receptor β-DAB2IP signals.

    PubMed

    Yeh, Chiuan-Ren; Ou, Zheng-Yu; Xiao, Guang-Qian; Guancial, Elizabeth; Yeh, Shuyuan

    2015-12-29

    Previous studies indicated the T cells, one of the most common types of immune cells existing in the microenvironment of renal cell carcinoma (RCC), may influence the progression of RCC. The potential linkage of T cells and the estrogen receptor beta (ERβ), a key player to impact RCC progression, however, remains unclear. Our results demonstrate that RCC cells can recruit more T cells than non-malignant kidney cells. Using an in vitro matrigel invasion system, we found infiltrating T cells could promote RCC cells invasion via increasing ERβ expression and transcriptional activity. Mechanism dissection suggested that co-culturing T cells with RCC cells released more T cell attraction factors, including IFN-γ, CCL3 and CCL5, suggesting a positive regulatory feed-back mechanism. Meanwhile, infiltrating T cells may also promote RCC cell invasion via increased ERβ and decreased DAB2IP expressions, and knocking down DAB2IP can then reverse the T cells-promoted RCC cell invasion. Together, our results suggest that infiltrating T cells may promote RCC cell invasion via increasing the RCC cell ERβ expression to inhibit the tumor suppressor DAB2IP signals. Further mechanism dissection showed that co-culturing T cells with RCC cells could produce more IGF-1 and FGF-7, which may enhance the ERβ transcriptional activity. The newly identified relationship between infiltrating T cells/ERβ/DAB2IP signals may provide a novel therapeutic target in the development of agents against RCC.

  17. CCL21 and IP-10 as blood biomarkers for pulmonary involvement in systemic lupus erythematosus patients.

    PubMed

    Odler, B; Bikov, A; Streizig, J; Balogh, C; Kiss, E; Vincze, K; Barta, I; Horváth, I; Müller, V

    2017-05-01

    Biomarkers for pulmonary manifestations in systemic lupus erythematosus (SLE) are missing. Plasma samples of nine SLE patients with known pulmonary involvement (SLE pulm ) and nine SLE patients without pulmonary involvement (SLE) were tested by multiplex microarray analysis for various cyto- and chemokines. Significantly decreased lung function paramters for forced vital capacity (FVC), total lung capacity (TLC), diffusion capacity for carbon monoxide (DL CO ) and diffusion of CO corrected on lung volume (KL CO ) were observed in SLE pulm as compared to SLE patients. CC chemokine ligand 21 (CCL21) and interferon gamma-induced protein 10 (IP-10) levels were significantly higher in SLE pulm , than in patients without pulmonary manifestations. CCL21 correlated negatively with DL CO ( r = -0.73; p < 0.01) and KL CO ( r = -0.62; p < 0.01), while IP-10 with FVC and forced expiratory volume one second. Receiver Operating Characteristics (ROC) analysis confirmed high sensitivity and specificity for the separation of SLE patients with and without pulmonary involvement for the chemokines CCL21 (Area Under Curve (AUC): 0.85; sensitivity%: 88.90; specificity%: 75.00; p < 0.01) and IP-10 (AUC: 0.82; sensitivity%: 66.67, specificity%: 100; p < 0.01). Pleuropulmonary manifestations in SLE patients associated with lung functional and DL CO /KL CO changes and were associated with significant increase in CCL21 and IP-10. These chemokines might serve as potential biomarkers of lung involvement in SLE patients.

  18. Inositol Hexakisphosphate Kinase-3 Regulates the Morphology and Synapse Formation of Cerebellar Purkinje Cells via Spectrin/Adducin

    PubMed Central

    Fu, Chenglai; Xu, Jing; Li, Ruo-Jing; Crawford, Joshua A.; Khan, A. Basit; Ma, Ting Martin; Cha, Jiyoung Y.; Snowman, Adele M.; Pletnikov, Mikhail V.

    2015-01-01

    The inositol hexakisphosphate kinases (IP6Ks) are the principal enzymes that generate inositol pyrophosphates. There are three IP6Ks (IP6K1, 2, and 3). Functions of IP6K1 and IP6K2 have been substantially delineated, but little is known of IP6K3's role in normal physiology, especially in the brain. To elucidate functions of IP6K3, we generated mice with targeted deletion of IP6K3. We demonstrate that IP6K3 is highly concentrated in the brain in cerebellar Purkinje cells. IP6K3 physiologically binds to the cytoskeletal proteins adducin and spectrin, whose mutual interactions are perturbed in IP6K3-null mutants. Consequently, IP6K3 knock-out cerebella manifest abnormalities in Purkinje cell structure and synapse number, and the mutant mice display deficits in motor learning and coordination. Thus, IP6K3 is a major determinant of cytoskeletal disposition and function of cerebellar Purkinje cells. SIGNIFICANCE STATEMENT We identified and cloned a family of three inositol hexakisphosphate kinases (IP6Ks) that generate the inositol pyrophosphates, most notably 5-diphosphoinositol pentakisphosphate (IP7). Of these, IP6K3 has been least characterized. In the present study we generated IP6K3 knock-out mice and show that IP6K3 is highly expressed in cerebellar Purkinje cells. IP6K3-deleted mice display defects of motor learning and coordination. IP6K3-null mice manifest aberrations of Purkinje cells with a diminished number of synapses. IP6K3 interacts with the cytoskeletal proteins spectrin and adducin whose altered disposition in IP6K3 knock-out mice may mediate phenotypic features of the mutant mice. These findings afford molecular/cytoskeletal mechanisms by which the inositol polyphosphate system impacts brain function. PMID:26245967

  19. Role of Ipsdienol, Ipsenol, and cis-Verbenol in chemical ecology of Ips avulsus, Ips calligraphus, and Ips grandicollis (Coleoptera: Curculionidae: Scolytinae)

    Treesearch

    Jeremy D. Allison; Jessica I. McKenney; Daniel R. Miller; Matthew L. Gimmel

    2012-01-01

    ABSTRACT Stressed or damaged pine (Pinus sp.) trees in the southeastern United States are often colonized simultaneously by three southern Ips species (Coleoptera: Curculionidae: Scolytinae): small southern pine engraver, Ips avulsus (Eichhoff); sixspined ips, Ips calligraphus (Germar); and...

  20. Comparison of gating dynamics of different IP3R channels with immune algorithm searching for channel parameter distributions

    NASA Astrophysics Data System (ADS)

    Cai, Xiuhong; Li, Xiang; Qi, Hong; Wei, Fang; Chen, Jianyong; Shuai, Jianwei

    2016-10-01

    The gating properties of the inositol 1, 4, 5-trisphosphate (IP3) receptor (IP3R) are determined by the binding and unbinding capability of Ca2+ ions and IP3 messengers. With the patch clamp experiments, the stationary properties have been discussed for Xenopus oocyte type-1 IP3R (Oo-IP3R1), type-3 IP3R (Oo-IP3R3) and Spodoptera frugiperda IP3R (Sf-IP3R). In this paper, in order to provide insights about the relation between the observed gating characteristics and the gating parameters in different IP3Rs, we apply the immune algorithm to fit the parameters of a modified DeYoung-Keizer model. By comparing the fitting parameter distributions of three IP3Rs, we suggest that the three types of IP3Rs have the similar open sensitivity in responding to IP3. The Oo-IP3R3 channel is easy to open in responding to low Ca2+ concentration, while Sf-IP3R channel is easily inhibited in responding to high Ca2+ concentration. We also show that the IP3 binding rate is not a sensitive parameter for stationary gating dynamics for three IP3Rs, but the inhibitory Ca2+ binding/unbinding rates are sensitive parameters for gating dynamics for both Oo-IP3R1 and Oo-IP3R3 channels. Such differences may be important in generating the spatially and temporally complex Ca2+ oscillations in cells. Our study also demonstrates that the immune algorithm can be applied for model parameter searching in biological systems.

  1. Startle Potentiation to Uncertain Threat as a Psychophysiological Indicator of Fear-based Psychopathology: An Examination across Multiple Internalizing Disorders

    PubMed Central

    Gorka, Stephanie M.; Lieberman, Lynne; Shankman, Stewart A.; Phan, K. Luan

    2016-01-01

    Heightened reactivity to uncertain threat (U-threat) is an important individual difference factor that may characterize fear-based internalizing psychopathologies (IPs) and distinguish them from distress/misery IPs. To date, however, the majority of existing research examining reactivity to U-threat has been within individuals with panic disorder and major depressive disorder (MDD) and no prior study has directly tested this hypothesis across multiple IPs. The current study therefore explored whether heightened reactivity to U-threat is a psychophysiological indicator of fear-based psychopathology across five groups: current 1) social anxiety disorder (SAD), 2) specific phobia (SP), 3) generalized anxiety disorder (GAD), 4) MDD, and 5) individuals with no history of psychopathology (controls). All 160 adults completed a well-validated threat-of-shock task designed to probe responses to predictable (P-) and U-threat. Startle eyeblink potentiation was recorded as an index of aversive arousal. Results indicated that individuals with SAD and SP evidenced greater startle potentiation to U-threat, but not P-threat, relative to individuals with GAD, MDD and controls (who did not differ). The current findings, along with the prior panic disorder and MDD literature, suggest that heightened reactivity to U-threat is a psychophysiological indicator of fear-based disorders and could represent a neurobiological organizing principle for internalizing psychopathology. The findings also suggest that individuals with fear disorders generally display a hypersensitivity to uncertain aversive events, which could contribute to their psychopathology. PMID:27868423

  2. A hybrid optical switch architecture to integrate IP into optical networks to provide flexible and intelligent bandwidth on demand for cloud computing

    NASA Astrophysics Data System (ADS)

    Yang, Wei; Hall, Trevor J.

    2013-12-01

    The Internet is entering an era of cloud computing to provide more cost effective, eco-friendly and reliable services to consumer and business users. As a consequence, the nature of the Internet traffic has been fundamentally transformed from a pure packet-based pattern to today's predominantly flow-based pattern. Cloud computing has also brought about an unprecedented growth in the Internet traffic. In this paper, a hybrid optical switch architecture is presented to deal with the flow-based Internet traffic, aiming to offer flexible and intelligent bandwidth on demand to improve fiber capacity utilization. The hybrid optical switch is capable of integrating IP into optical networks for cloud-based traffic with predictable performance, for which the delay performance of the electronic module in the hybrid optical switch architecture is evaluated through simulation.

  3. NASA Electronic Parts and Packaging Field Programmable Gate Array Single Event Effects Test Guideline Update

    NASA Technical Reports Server (NTRS)

    Berg, Melanie D.; LaBel, Kenneth A.

    2018-01-01

    The following are updated or new subjects added to the FPGA SEE Test Guidelines manual: academic versus mission specific device evaluation, single event latch-up (SEL) test and analysis, SEE response visibility enhancement during radiation testing, mitigation evaluation (embedded and user-implemented), unreliable design and its affects to SEE Data, testing flushable architectures versus non-flushable architectures, intellectual property core (IP Core) test and evaluation (addresses embedded and user-inserted), heavy-ion energy and linear energy transfer (LET) selection, proton versus heavy-ion testing, fault injection, mean fluence to failure analysis, and mission specific system-level single event upset (SEU) response prediction. Most sections within the guidelines manual provide information regarding best practices for test structure and test system development. The scope of this manual addresses academic versus mission specific device evaluation and visibility enhancement in IP Core testing.

  4. NASA Electronic Parts and Packaging (NEPP) Field Programmable Gate Array (FPGA) Single Event Effects (SEE) Test Guideline Update

    NASA Technical Reports Server (NTRS)

    Berg, Melanie D.; LaBel, Kenneth A.

    2018-01-01

    The following are updated or new subjects added to the FPGA SEE Test Guidelines manual: academic versus mission specific device evaluation, single event latch-up (SEL) test and analysis, SEE response visibility enhancement during radiation testing, mitigation evaluation (embedded and user-implemented), unreliable design and its affects to SEE Data, testing flushable architectures versus non-flushable architectures, intellectual property core (IP Core) test and evaluation (addresses embedded and user-inserted), heavy-ion energy and linear energy transfer (LET) selection, proton versus heavy-ion testing, fault injection, mean fluence to failure analysis, and mission specific system-level single event upset (SEU) response prediction. Most sections within the guidelines manual provide information regarding best practices for test structure and test system development. The scope of this manual addresses academic versus mission specific device evaluation and visibility enhancement in IP Core testing.

  5. Methemoglobinemia hemotoxicity of some antimalarial 8-aminoquinoline analogues and their hydroxylated derivatives: density functional theory computation of ionization potentials

    USDA-ARS?s Scientific Manuscript database

    The administration of primaquine (PQ), an essential drug for treatment and radical cure of malaria, can lead to methemoglobin formation and life-threatening hemolysis for glucose-6-phosphate dehydrogenase deficient patients. The ionization potential (IP, a quantitative measure of the ability to lose...

  6. Vinpocetine and piracetam exert antinociceptive effect in visceral pain model in mice.

    PubMed

    Abdel Salam, Omar M E

    2006-01-01

    The effect of vinpocetine or piracetam on thermal and visceral pain was studied in mice. In the hot plate test, vinpocetine (0.9 and 1.8 mg/kg), but not piracetam, produced a reduction in nociceptive response. Vinpocetine (0.45-1.8 mg/kg, ip) or piracetam (75-300 mg/kg, ip) caused dose-dependent inhibition of the abdominal constrictions evoked by ip injection of acetic acid. The effect of vinpocetine or piracetam was markedly potentiated by co-administration of propranolol, guanethidine, atropine, naloxone, yohimbine or prazosin. The marked potentiation of antinociception occurred upon a co-administration of vinpocetine and baclofen (5 or 10 mg/kg). In contrast, piracetam antagonized antinociception caused by the low (5 mg/kg), but not the high (10 mg/kg) dose of baclofen. The antinociception caused by vinpocetine was reduced by sulpiride; while that of piracetam was enhanced by haloperidol or sulpiride. Either vinpocetine or piracetam enhanced antinociception caused by imipramine. The antinociceptive effects of vinpocetine or piracetam were blocked by prior administration of theophylline. Low doses of either vinpocetine or piracetam reduced immobility time in the Porsolt's forced-swimming test. This study indicates that vinpocetine and piracetam possess visceral antinociceptive properties. This effect depends on activation of adenosine receptors. Piracetam in addition inhibits GABA-mediated antinociception.

  7. Lipid-derived free radical production in superantigen-induced interstitial pneumonia

    PubMed Central

    Miyakawa, Hisako; Mason, Ronald P.; Jiang, JinJie; Kadiiska, Maria B.

    2009-01-01

    We studied the free radical generation involved in the development of interstitial pneumonia (IP) in an animal model of autoimmune disease. We observed an electron spin resonance (ESR) spectrum of α-(4-pyridyl-1-oxide)-N-tert-butylnitrone (POBN) radical adducts detected in the lipid extract of lungs in autoimmune-prone mice after intratracheal instillation of staphylococcal enterotoxin B. The POBN adducts detected by ESR were paralleled by infiltration of macrophages and neutrophils in the bronchoalveolar lavage fluid. To further investigate the mechanism of free radical generation, mice were pretreated with the macrophage toxicant gadolinium chloride, which significantly suppressed the radical generation. Free radical generation was also decreased by pretreatment with the xanthine oxidase (XO) inhibitor allopurinol, the iron chelator Desferal, and the inducible nitric oxide synthase (iNOS) inhibitor 1400W. Histopathologically, these drugs significantly reduced both the cell infiltration to alveolar septal walls and the synthesis of pulmonary collagen fibers. Experiments with NADPH oxidase knockout mice showed that NADPH oxidase did not contribute to lipid radical generation. These results suggest that lipid-derived carbon-centered free radical production is important in the manifestation of IP and that a macrophage toxicant, an XO inhibitor, an iron chelator, and an iNOS inhibitor protect against both radical generation and the manifestation of IP. PMID:19376221

  8. Asymmetric quantum-well structures for AlGaN/GaN/AlGaN resonant tunneling diodes

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

    Yang, Lin'an, E-mail: layang@xidian.edu.cn; Li, Yue; Wang, Ying

    Asymmetric quantum-well (QW) structures including the asymmetric potential-barrier and the asymmetric potential-well are proposed for AlGaN/GaN/AlGaN resonant tunneling diodes (RTDs). Theoretical investigation gives that an appropriate decrease in Al composition and thickness for emitter barrier as well as an appropriate increase of both for collector barrier can evidently improve the negative-differential-resistance characteristic of RTD. Numerical simulation shows that RTD with a 1.5-nm-thick GaN well sandwiched by a 1.3-nm-thick Al{sub 0.15}Ga{sub 0.85}N emitter barrier and a 1.7-nm-thick Al{sub 0.25}Ga{sub 0.75}N collector barrier can yield the I-V characteristic having the peak current (Ip) and the peak-to-valley current ratio (PVCR) of 0.39 A andmore » 3.6, respectively, about double that of RTD with a 1.5-nm-thick Al{sub 0.2}Ga{sub 0.8}N for both barriers. It is also found that an introduction of InGaN sub-QW into the diode can change the tunneling mode and achieve higher transmission coefficient of electron. The simulation demonstrates that RTD with a 2.8-nm-thick In{sub 0.03}Ga{sub 0.97}N sub-well in front of a 2.0-nm-thick GaN main-well can exhibit the I-V characteristic having Ip and PVCR of 0.07 A and 11.6, about 7 times and double the value of RTD without sub-QW, respectively. The purpose of improving the structure of GaN-based QW is to solve apparent contradiction between the device structure and the device manufacturability of new generation RTDs for sub-millimeter and terahertz applications.« less

  9. MDMA ‘ecstasy’ increases cerebral cortical perfusion determined by bolus-tracking arterial spin labelling (btASL) MRI

    PubMed Central

    Rouine, J; Gobbo, O L; Campbell, M; Gigliucci, V; Ogden, I; McHugh Smith, K; Duffy, P; Behan, B; Byrne, D; Kelly, M E; Blau, C W; Kerskens, C M; Harkin, A

    2013-01-01

    Background and Purpose The purpose of this study was to assess cerebral perfusion changes following systemic administration of the recreational drug 3,4-methylendioxymethamphetamine (MDMA ‘ecstasy’) to rats. Experimental Approach Cerebral perfusion was quantified using bolus-tracking arterial spin labelling (btASL) MRI. Rats received MDMA (20 mg·kg−1; i.p.) and were assessed 1, 3 or 24 h later. Rats received MDMA (5 or 20 mg·kg−1; i.p.) and were assessed 3 h later. In addition, rats received MDMA (5 or 10 mg·kg−1; i.p.) or saline four times daily over 2 consecutive days and were assessed 8 weeks later. Perfusion-weighted images were generated in a 7 tesla (7T) MRI scanner and experimental data was fitted to a quantitative model of cerebral perfusion to generate mean transit time (MTT), capillary transit time (CTT) and signal amplitude. Key Results MDMA reduces MTT and CTT and increases amplitude in somatosensory and motor cortex 1 and 3 h following administration, indicative of an increase in perfusion. Prior exposure to MDMA provoked a long-term reduction in cortical 5-HT concentration, but did not produce a sustained effect on cerebral cortical perfusion. The response to acute MDMA challenge (20 mg·kg−1; i.p.) was attenuated in these animals indicating adaptation in response to prior MDMA exposure. Conclusions and Implications MDMA provokes changes in cortical perfusion, which are quantifiable by btASL MRI, a neuroimaging tool with translational potential. Future studies are directed towards elucidation of the mechanisms involved and correlating changes in cerebrovascular function with potential behavioural deficits associated with drug use. PMID:23517012

  10. Biomonitoring of PAHs by using Quercus ilex leaves: Source diagnostic and toxicity assessment

    NASA Astrophysics Data System (ADS)

    De Nicola, Flavia; Claudia, Lancellotti; MariaVittoria, Prati; Giulia, Maisto; Anna, Alfani

    2011-03-01

    Quercus ilex L. leaves were sampled at nineteen urban sites and two remote sites in order to evaluate PAH contamination degree. One-, two- and three-year-old leaves were collected and leaf lipid content was measured to investigate the influence of leaf age and lipids in PAH accumulation. Some PAH diagnostic ratios, such as Ant/Ant + Phen, Flt/Flt + Pyr, B[a]A/B[a]A + Crys and IP/IP + B[g,h,i]P, were calculated. The results suggest that Q. ilex leaves are effective biomonitors of PAH air contamination: in fact, a great PAH accumulation in leaves from the urban areas, until 30-time higher compared to those from the remote sites, has been observed. At each site, the similar total PAH concentrations in leaves of different age, probably due to a canopy effect, indicate an ability of all leaf age classes to monitor local PAH concentrations in air, remarking practical implications for air biomonitoring. The findings suggest that PAH adsorption in Q. ilex leaves does not result limited by leaf lipid content. Moreover, this study demonstrates the source-diagnostic potential of Q. ilex leaves, because, in particular, the Flt/Flt + Pyr and IP/IP + B[g,h,i]P ratios indicate vehicular traffic as the main source of PAHs in the urban areas and wood combustion in the remote areas. Moreover, to distinguish biomass combustion source, a promising tracer PAH as DB[a,h]A could be used. The high contribution of DB[a,h]A to total PAH concentrations at the remote sites determines a high carcinogenic potential in this area, similar to that calculated for the urban area where the carcinogenic PAH concentrations in absolute values are often higher.

  11. Anticonvulsant, anxiolytic and discriminative effects of the AMPA antagonist 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline (NBQX).

    PubMed

    Swedberg, M D; Jacobsen, P; Honoré, T

    1995-09-01

    The anticonvulsant effects of 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline (NBQX), phencyclidine (PCP) and diazepam against audiogenic seizures in DBA/2 mice and against seizures induced by methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate (DMCM) in NMRI mice were compared. Motor impairment was assessed in a rotarod apparatus in DBA/2 as well as NMRI mice. At 30 min after i.p. administration, NBQX was as effective as PCP and diazepam in protecting against audiogenic seizures and had a therapeutic ratio slightly higher than diazepam's and 7-fold higher than PCP's. Whereas diazepam was fully effective, NBQX and PCP were both ineffective against seizures induced by DMCM 30 min after i.p. administration. The anticonvulsant potential and motor-impairing effects of NBQX were evaluated further by the i.p. and the i.v. routes at different time points after administration. At all pretreatment intervals, NBQX protected against audiogenic seizures more potently than it produced motor impairment. NBQX administered i.p. protected against DMCM-induced seizures when given 15 min but not 5 min before testing, whereas after i.v. administration NBQX produced anticonvulsant and motor-impairing effects in the same dose range. NBQX only slightly and non-dose-dependently attenuated the discriminative effects of pentylenetetrazole in rats, showing a limited anxiolytic potential. NBQX produced no PCP-like or morphine-like discriminative effects in rats, suggesting lack of PCP or opiate-like subjective effects. These data demonstrate that NBQX has anticonvulsant effects, has limited anxiolytic effects, and does not produce subjective effects of PCP or opiate type.

  12. Connections between intraparietal sulcus and a sensorimotor network underpin sustained tactile attention.

    PubMed

    Goltz, Dominique; Gundlach, Christopher; Nierhaus, Till; Villringer, Arno; Müller, Matthias; Pleger, Burkhard

    2015-05-20

    Previous studies on sustained tactile attention draw conclusions about underlying cortical networks by averaging over experimental conditions without considering attentional variance in single trials. This may have formed an imprecise picture of brain processes underpinning sustained tactile attention. In the present study, we simultaneously recorded EEG-fMRI and used modulations of steady-state somatosensory evoked potentials (SSSEPs) as a measure of attentional trial-by-trial variability. Therefore, frequency-tagged streams of vibrotactile stimulations were simultaneously presented to both index fingers. Human participants were cued to sustain attention to either the left or right finger stimulation and to press a button whenever they perceived a target pulse embedded in the to-be-attended stream. In-line with previous studies, a classical general linear model (GLM) analysis based on cued attention conditions revealed increased activity mainly in somatosensory and cerebellar regions. Yet, parametric modeling of the BOLD response using simultaneously recorded SSSEPs as a marker of attentional trial-by-trial variability quarried the intraparietal sulcus (IPS). The IPS in turn showed enhanced functional connectivity to a modality-unspecific attention network. However, this was only revealed on the basis of cued attention conditions in the classical GLM. By considering attentional variability as captured by SSSEPs, the IPS showed increased connectivity to a sensorimotor network, underpinning attentional selection processes between competing tactile stimuli and action choices (press a button or not). Thus, the current findings highlight the potential value by considering attentional variations in single trials and extend previous knowledge on the role of the IPS in tactile attention. Copyright © 2015 the authors 0270-6474/15/357938-12$15.00/0.

  13. Electric conductivity for laboratory and field monitoring of induced partial saturation (IPS) in sands

    NASA Astrophysics Data System (ADS)

    Kazemiroodsari, Hadi

    Liquefaction is loss of shear strength in fully saturated loose sands caused by build-up of excess pore water pressure, during moderate to large earthquakes, leading to catastrophic failures of structures. Currently used liquefaction mitigation measures are often costly and cannot be applied at sites with existing structures. An innovative, practical, and cost effective liquefaction mitigation technique titled "Induced Partial Saturation" (IPS) was developed by researchers at Northeastern University. The IPS technique is based on injection of sodium percarbonate solution into fully saturated liquefaction susceptible sand. Sodium percarbonate dissolves in water and breaks down into sodium and carbonate ions and hydrogen peroxide which generates oxygen gas bubbles. Oxygen gas bubbles become trapped in sand pores and therefore decrease the degree of saturation of the sand, increase the compressibility of the soil, thus reduce its potential for liquefaction. The implementation of IPS required the development and validation of a monitoring and evaluation technique that would help ensure that the sands are indeed partially saturated. This dissertation focuses on this aspect of the IPS research. The monitoring system developed was based on using electric conductivity fundamentals and probes to detect the transport of chemical solution, calculate degree of saturation of sand, and determine the final zone of partial saturation created by IPS. To understand the fundamentals of electric conductivity, laboratory bench-top tests were conducted using electric conductivity probes and small specimens of Ottawa sand. Bench-top tests were used to study rate of generation of gas bubbles due to reaction of sodium percarbonate solution in sand, and to confirm a theory based on which degree of saturation were calculated. In addition to bench-top tests, electric conductivity probes were used in a relatively large sand specimen prepared in a specially manufactured glass tank. IPS was implemented in the prepared specimen to validate the numerical simulation model and explore the use of conductivity probes to detect the transport of chemical solution, estimate degree of saturation achieved due to injection of chemical solution, and evaluate final zone of partial saturation. The conductivity probe and the simulation results agreed well. To study the effect of IPS on liquefaction response of the sand specimen, IPS was implemented in a large (2-story high) sand specimen prepared in the laminar box of NEES Buffalo and then the specimen was subjected to harmonic shaking. Electric conductivity probes were used in the specimen treatment by controlling the duration and spacing of injection of the chemical solution, in monitoring the transport of chemical solution, in the estimation of zone of partial saturation achieved, and in the estimation of degree of saturation achieved due to implementation of IPS. The conductivity probes indicated partial saturation of the specimen. The shaking tests results confirmed the partial saturation state of the sand specimen. In addition, to the laboratory works, electric conductivity probes were used in field implementation of IPS in a pilot test at the Wildlife Liquefaction Array (WLA) of NEES UCSB site. The conductivity probes in the field test helped decide the optimum injection pressure, the injection tube spacing, and the degree of saturation that could be achieved in the field. The various laboratory and field tests confirmed that electric conductivity and the probes devised and used can be invaluable in the implementation of IPS, by providing information regarding transport of the chemical solution, the spacing of injection tubes, duration of injection, and the zone and degree of partial saturation caused by IPS.

  14. Role of calcium stores and membrane voltage in the generation of slow wave action potentials in guinea-pig gastric pylorus

    PubMed Central

    Van Helden, D F; Imtiaz, M S; Nurgaliyeva, K; von der Weid, P-Y; Dosen, P J

    2000-01-01

    Intracellular recordings made in single bundle strips of a visceral smooth muscle revealed rhythmic spontaneous membrane depolarizations termed slow waves (SWs). These exhibited ‘pacemaker’ and ‘regenerative’ components composed of summations of more elementary events termed spontaneous transient depolarizations (STDs). STDs and SWs persisted in the presence of tetrodotoxin, nifedipine and ryanodine, and upon brief exposure to Ca2+-free Cd2+-containing solutions; they were enhanced by ACh and blocked by BAPTA AM, cyclopiazonic acid and caffeine. SWs were also inhibited in heparin-loaded strips. SWs were observed over a wide range of membrane potentials (e.g. −80 to −45 mV) with increased frequencies at more depolarized potentials. Regular spontaneous SW activity in this preparation began after 1–3 h superfusion of the tissue with physiological saline following the dissection procedure. Membrane depolarization applied before the onset of this activity induced bursts of STD-like events (termed the ‘initial’ response) which, when larger than threshold levels initiated regenerative responses. The combined initial-regenerative waveform was termed the SW-like action potential. Voltage-induced responses exhibited large variable latencies (typical range 0.3–4 s), refractory periods of ≈11 s and a pharmacology that was indistinguishable from those of STDs and spontaneous SWs. The data indicate that SWs arise through more elementary inositol 1,4,5-trisphosphate (IP3) receptor-induced Ca2+ release events which rhythmically synchronize to trigger regenerative Ca2+ release and induce inward current across the plasmalemma. The finding that action potentials, which were indistinguishable from SWs, could be evoked by depolarization suggests that membrane potential modulates IP3 production. Voltage feedback on intracellular IP3-sensitive Ca2+ release is likely to have a major influence on the generation and propagation of SWs. PMID:10747196

  15. Examining Correlates of Problematic Internet Pornography Use Among University Students

    PubMed Central

    Harper, Cody; Hodgins, David C.

    2016-01-01

    Background and aims The phenomenon of Internet pornography (IP) addiction is gainingincreasing attention in the popular media and psychological research. What has not been tested empirically is how frequency and amount ofIP use, along with other individual characteristics, are related tosymptoms of IP addiction. Methods 105 female and 86 male university students (mean age 21) from Calgary,Canada, were administered measures of IP use, psychosocial functioning (anxiety and depression, life and relationship satisfaction), addictivepropensities, and addictive IP use. Results Men reported earlier age of exposure and more frequent current IP use than women. Individuals not in relationships reported more frequent use than those in relationships. Frequency of IP use wasnot generally correlated with psychosocial functioning but was significantly positively correlated with level of IP addiction. Higher level of IP addiction was associated with poorer psychosocial functioning and problematic alcohol, cannabis, gambling and, in particular, video game use. A curvilinear association was found between frequency of IP use and level of addiction such that daily or greater IP use was associated with a sharp rise in addictive IP scores. Discussion The failure to find a strong significant relationship between IP use and general psychosocial functioning suggests that the overall effect of IP use is not necessarily harmful in and of itself. Addictiveuse of IP, which is associated with poorer psychosocial functioning, emerges when people begin to use IP daily. PMID:27156383

  16. Time-Dependent Simulations of Fast-Wave Heated High-Non-Inductive-Fraction H-Mode Plasmas in the National Spherical Torus Experiment Upgrade

    NASA Astrophysics Data System (ADS)

    Taylor, Gary; Bertelli, Nicola; Gerhardt, Stefan P.; Hosea, Joel C.; Mueller, Dennis; Perkins, Rory J.; Poli, Francesca M.; Wilson, James R.; Raman, Roger

    2017-10-01

    30 MHz fast-wave heating may be an effective tool for non-inductively ramping low-current plasmas to a level suitable for initiating up to 12 MW of neutral beam injection on the National Spherical Tokamak Experiment Upgrade (NSTX-U). Previously on NSTX 30 MHz fast wave heating was shown to efficiently and rapidly heat electrons; at the NSTX maximum axial toroidal magnetic field (BT(0)) of 0.55 T, 1.4 MW of 30 MHz heating increased the central electron temperature from 0.2 to 2 keV in 30 ms and generated an H-mode plasma with a non-inductive fraction (fNI) ˜ 0.7 at a plasma current (Ip) of 300 kA. NSTX-U will operate at BT(0) up to 1 T, with up to 4 MW of 30 MHz power (Prf). Predictive TRANSP free boundary transport simulations, using the TORIC full wave spectral code to calculate the fast-wave heating and current drive, have been run for NSTX-U Ip = 300 kA H-mode plasmas. Favorable scaling of fNI with 30 MHz heating power is predicted, with fNI ≥ 1 for Prf ≥ 2 MW.

  17. Femtosecond-picosecond laser photolysis studies on the dynamics of excited charge-transfer complexes: Aromatic hydrocarbon-acid anhydride, -tetracyanoethylene, and -tetracyanoquinodimethane systems in acetonitrile solutions

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

    Asahi, Tsuyoshi; Mataga, Noboru

    1991-03-07

    Formation processes of contact ion pairs (CIP) from the excited Franck-Condon (FC) state of charge-transfer (CT) complexes of aromatic hydrocarbons with acid anhydride as well as cyano compound acceptors in acetonitrile solution and charge recombination (CR) rates (k{sub CR}{sup CIP}) of produced CIP states have been investigated by femtosecond and picosecond laser phototlysis and time-resolved absorption spectral measurements covering a wide range of free energy gap-{Delta}G{degree}{sub ip} between the ion pair and the ground state. It has been confirmed that the CIP formation becomes faster and k{sub CR}{sup CIP} of the produced CIP increases with increase of the strengths ofmore » the electron donor (D) and acceptor (A) in the complex, i.e., with decrease of the {minus}{Delta}G{degree}{sub ip} value. This peculiar energy gap dependence of k{sub CR}{sup CIP}, quite different from the bell-shaped one observed in the case of the solvent-separated ion pairs (SSIP) or loose ion pairs (LIP) formed by encounter between fluorescer and quencher in the fluoresence quenching reaction, has been interpreted by assuming the change of electronic and geometrical structures of CIP depending on the strengths of D and A.« less

  18. A Thin Film Nanocomposite Membrane with MCM-41 Silica Nanoparticles for Brackish Water Purification.

    PubMed

    Kadhom, Mohammed; Yin, Jun; Deng, Baolin

    2016-12-06

    Thin film nanocomposite (TFN) membranes containing MCM-41 silica nanoparticles (NPs) were synthesized by the interfacial polymerization (IP) process. An m -phenylenediamine (MPD) aqueous solution and an organic phase with trimesoyl chloride (TMC) dissolved in isooctane were used in the IP reaction, occurring on a nanoporous polysulfone (PSU) support layer. Isooctane was introduced as the organic solvent for TMC in this work due to its intermediate boiling point. MCM-41 silica NPs were loaded in MPD and TMC solutions in separate experiments, in a concentration range from 0 to 0.04 wt %, and the membrane performance was assessed and compared based on salt rejection and water flux. The prepared membranes were characterized via scanning electron microscopy (SEM), transmission electron microscopy (TEM), contact angle measurement, and attenuated total reflection Fourier transform infrared (ATR FT-IR) analysis. The results show that adding MCM-41 silica NPs into an MPD solution yields slightly improved and more stable results than adding them to a TMC solution. With 0.02% MCM-41 silica NPs in the MPD solution, the water flux was increased from 44.0 to 64.1 L/m²·h, while the rejection virtually remained the same at 95% (2000 ppm NaCl saline solution, 25 °C, 2068 kPa (300 psi)).

  19. ChIP and ChIP-Related Techniques: Expanding the Fields of Application and Improving ChIP Performance.

    PubMed

    Visa, Neus; Jordán-Pla, Antonio

    2018-01-01

    Protein-DNA interactions in vivo can be detected and quantified by chromatin immunoprecipitation (ChIP). ChIP has been instrumental for the advancement of epigenetics and has set the groundwork for the development of a number of ChIP-related techniques that have provided valuable information about the organization and function of genomes. Here, we provide an introduction to ChIP and discuss the applications of ChIP in different research areas. We also review some of the strategies that have been devised to improve ChIP performance.

  20. The prevalence of human papillomavirus infection in Iranian patients with sinonasal inverted papilloma.

    PubMed

    Jalilvand, Somayeh; Saidi, Masoumeh; Shoja, Zabihollah; Ghavami, Nastaran; Hamkar, Rasool

    2016-03-01

    Inverted papilloma (IP) is an uncommon disease which arises in the mucosal membrane of the nasal cavity and paranasal sinus. It has been proposed that human papillomavirus (HPV) is the causal agent in the pathogenesis of IP and plays a key role in the progression from benign IP to malignancy. As there are no prior studies that focus on an Iranian population, this study intended to characterize the prevalence of HPV types in benign and malignant forms of IP. In this retrospective study, we included a total of 40 IP patients [37 benign IP and 3 IP/squamous cell carcinoma (SCC)] who were referred to Amiralam Hospital in Tehran from 2004-2006. HPV was detected in 18.9% and 100% of IP and IP/SCC cases, respectively. In all HPV positive cases of IP and IP/SCC cases, HPV6/11 and HPV16/18 were detected, respectively. Therefore, HPV types were different between the IP and IP/SCC patients, and this difference was statistically significant (p = 0.002). This study suggests that HPV6 and 11 may be involved in the development of IP, but HPV16 and 18 likely play an important role in the progression from benign to malignant form of IP. Copyright © 2015. Published by Elsevier Taiwan LLC.

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