WorldWideScience

Sample records for primary charge-separation act

  1. Energetics and kinetics of primary charge separation in bacterial photosynthesis.

    Science.gov (United States)

    LeBard, David N; Kapko, Vitaliy; Matyushov, Dmitry V

    2008-08-21

    We report the results of molecular dynamics (MD) simulations and formal modeling of the free-energy surfaces and reaction rates of primary charge separation in the reaction center of Rhodobacter sphaeroides. Two simulation protocols were used to produce MD trajectories. Standard force-field potentials were employed in the first protocol. In the second protocol, the special pair was made polarizable to reproduce a high polarizability of its photoexcited state observed by Stark spectroscopy. The charge distribution between covalent and charge-transfer states of the special pair was dynamically adjusted during the simulation run. We found from both protocols that the breadth of electrostatic fluctuations of the protein/water environment far exceeds previous estimates, resulting in about 1.6 eV reorganization energy of electron transfer in the first protocol and 2.5 eV in the second protocol. Most of these electrostatic fluctuations become dynamically frozen on the time scale of primary charge separation, resulting in much smaller solvation contributions to the activation barrier. While water dominates solvation thermodynamics on long observation times, protein emerges as the major thermal bath coupled to electron transfer on the picosecond time of the reaction. Marcus parabolas were obtained for the free-energy surfaces of electron transfer by using the first protocol, while a highly asymmetric surface was obtained in the second protocol. A nonergodic formulation of the diffusion-reaction electron-transfer kinetics has allowed us to reproduce the experimental results for both the temperature dependence of the rate and the nonexponential decay of the population of the photoexcited special pair.

  2. Antenna entropy in plant photosystems does not reduce the free energy for primary charge separation.

    Science.gov (United States)

    Jennings, Robert C; Zucchelli, Giuseppe

    2014-12-01

    We have investigated the concept of the so-called "antenna entropy" of higher plant photosystems. Several interesting points emerge: 1. In the case of a photosystemwhich harbours an excited state, the “antenna entropy” is equivalent to the configurational (mixing) entropy of a thermodynamic canonical ensemble. The energy associated with this parameter has been calculated for a hypothetical isoenergetic photosystem, photosystem I and photosystem II, and comes out in the range of 3.5 - 8% of the photon energy considering 680 nm. 2. The “antenna entropy” seems to be a rather unique thermodynamic phenomenon, in as much as it does not modify the free energy available for primary photochemistry, as has been previously suggested. 3. It is underlined that this configurational (mixing) entropy, unlike heat dispersal in a thermal system, does not involve energy dilution. This points out an important difference between thermal and electronic energy dispersal. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Pathways and timescales of primary charge separation in the photosystem II reaction center as revealed by a simultaneous fit of time-resolved fluorescence and transient absorption

    NARCIS (Netherlands)

    Novoderezhkin, V.I.; Andrizhiyevskaya, E.G.; Dekker, J.P.; van Grondelle, R.

    2005-01-01

    We model the dynamics of energy transfer and primary charge separation in isolated photosystem II (PSII) reaction centers. Different exciton models with specific site energies of the six core pigments and two peripheral chlorophylls (Chls) in combination with different charge transfer schemes have

  4. Physical stage of photosynthesis charge separation

    Science.gov (United States)

    Yakovlev, A. G.; Shuvalov, V. A.

    2016-06-01

    An analytical review is given concerning the biophysical aspects of light-driven primary charge separation in photosynthesis reaction centers (RCs) which are special pigment-protein complexes residing in a cell membrane. The primary (physical) stage of charge separation occurs in the pico- and femtosecond ranges and consists of transferring an electron along the active A-branch of pigments. The review presents vast factual material on both the general issues of primary photosynthesis and some more specific topics, including (1) the role of the inactive B-branch of pigments, (2) the effect of the protein environment on the charge separation, and (3) the participation of monomeric bacteriochlorophyll BA in primary electron acceptance. It is shown that the electron transfer and stabilization are strongly influenced by crystallographic water and tyrosine M210 molecules from the nearest environment of BA. A linkage between collective nuclear motions and electron transfer upon charge separation is demonstrated. The nature of the high quantum efficiency of primary charge separation reactions is discussed.

  5. Energy storage device with large charge separation

    Science.gov (United States)

    Holme, Timothy P.; Prinz, Friedrich B.; Iancu, Andrei T.

    2018-04-03

    High density energy storage in semiconductor devices is provided. There are two main aspects of the present approach. The first aspect is to provide high density energy storage in semiconductor devices based on formation of a plasma in the semiconductor. The second aspect is to provide high density energy storage based on charge separation in a p-n junction.

  6. Cofactors involved in light-driven charge separation in photosystem I identified by subpicosecond infrared spectroscopy.

    Science.gov (United States)

    Di Donato, Mariangela; Stahl, Andreas D; van Stokkum, Ivo H M; van Grondelle, Rienk; Groot, Marie-Louise

    2011-02-01

    Photosystem I is one of the key players in the conversion of solar energy into chemical energy. While the chlorophyll dimer P(700) has long been identified as the primary electron donor, the components involved in the primary charge separation process in PSI remain undetermined. Here, we have studied the charge separation dynamics in Photosystem I trimers from Synechococcus elongatus by femtosecond vis-pump/mid-infrared-probe spectroscopy upon excitation at 700, 710, and 715 nm. Because of the high specificity of the infrared region for the redox state and small differences in the molecular structure of pigments, we were able to clearly identify specific marker bands indicating chlorophyll (Chl) oxidation. Magnitudes of chlorophyll cation signals are observed to increase faster than the time resolution of the experiment (~0.2 ps) upon both excitation conditions: 700 nm and selective red excitation. Two models, involving either ultrafast charge separation or charge transfer character of the red pigments in PSI, are discussed to explain this observation. A further increase in the magnitudes of cation signals on a subpicosecond time scale (0.8-1 ps) indicates the formation of the primary radical pair. Evolution in the cation region with time constants of 7 and 40 ps reveals the formation of the secondary radical pair, involving a secondary electron donor. Modeling of the data allows us to extract the spectra of the two radical pairs, which have IR signatures consistent with A+A₀- and P₇₀₀+A₁-. We conclude that the cofactor chlorophyll A acts as the primary donor in PSI. The existence of an equilibrium between the two radical pairs we interpret as concerted hole/electron transfer between the pairs of electron donors and acceptors, until after 40 ps, relaxation leads to a full population of the P₇₀₀+A₁. radical pair.

  7. Quantum modeling of ultrafast photoinduced charge separation

    Science.gov (United States)

    Rozzi, Carlo Andrea; Troiani, Filippo; Tavernelli, Ivano

    2018-01-01

    Phenomena involving electron transfer are ubiquitous in nature, photosynthesis and enzymes or protein activity being prominent examples. Their deep understanding thus represents a mandatory scientific goal. Moreover, controlling the separation of photogenerated charges is a crucial prerequisite in many applicative contexts, including quantum electronics, photo-electrochemical water splitting, photocatalytic dye degradation, and energy conversion. In particular, photoinduced charge separation is the pivotal step driving the storage of sun light into electrical or chemical energy. If properly mastered, these processes may also allow us to achieve a better command of information storage at the nanoscale, as required for the development of molecular electronics, optical switching, or quantum technologies, amongst others. In this Topical Review we survey recent progress in the understanding of ultrafast charge separation from photoexcited states. We report the state-of-the-art of the observation and theoretical description of charge separation phenomena in the ultrafast regime mainly focusing on molecular- and nano-sized solar energy conversion systems. In particular, we examine different proposed mechanisms driving ultrafast charge dynamics, with particular regard to the role of quantum coherence and electron-nuclear coupling, and link experimental observations to theoretical approaches based either on model Hamiltonians or on first principles simulations.

  8. Spin-Charge Separation in Finite Length Metallic Carbon Nanotubes

    KAUST Repository

    Zhang, Yongyou; Zhang, Qingyun; Schwingenschlö gl, Udo

    2017-01-01

    Using time-dependent density functional theory, we study the optical excitations in finite length carbon nanotubes. Evidence of spin-charge separation is given in the spacetime domain. We demonstrate that the charge density wave is due to collective

  9. Microscopic dynamics of charge separation at the aqueous electrochemical interface

    OpenAIRE

    Kattirtzi, John A.; Limmer, David T.; Willard, Adam P.

    2017-01-01

    We have used molecular simulation and methods of importance sampling to study the thermodynamics and kinetics of ionic charge separation at a liquid water-metal interface. We have considered this process using canonical examples of two different classes of ions: a simple alkali-halide pair, Na$^+$I$^-$, or classical ions, and the products of water autoionization, H$_3$O$^+$OH$^-$, or water ions. We find that for both ion classes, the microscopic mechanism of charge separation, including water...

  10. Exploring primary care activities in ACT teams.

    Science.gov (United States)

    Vanderlip, Erik R; Williams, Nancy A; Fiedorowicz, Jess G; Katon, Wayne

    2014-05-01

    People with serious mental illness often receive inadequate primary and preventive care services. Federal healthcare reform endorses team-based care that provides high quality primary and preventive care to at risk populations. Assertive community treatment (ACT) teams offer a proven, standardized treatment approach effective in improving mental health outcomes for the seriously mentally ill. Much is known about the effectiveness of ACT teams in improving mental health outcomes, but the degree to which medical care needs are addressed is not established. The purpose of this study was to explore the extent to which ACT teams address the physical health of the population they serve. ACT team leaders were invited to complete an anonymous, web-based survey to explore attitudes and activities involving the primary care needs of their clients. Information was collected regarding the use of health screening tools, physical health assessments, provision of medical care and collaboration with primary care systems. Data was analyzed from 127 team leaders across the country, of which 55 completed the entire survey. Nearly every ACT team leader believed ACT teams have a role in identifying and managing the medical co-morbidities of their clientele. ACT teams report participation in many primary care activities. ACT teams are providing a substantial amount of primary and preventive services to their population. The survey suggests standardization of physical health identification, management or referral processes within ACT teams may result in improved quality of medical care. ACT teams are in a unique position to improve physical health care by virtue of having medically trained staff and frequent, close contact with their clients.

  11. Spin-charge separation in ultra-cold quantum gases

    OpenAIRE

    Recati, A.; Fedichev, P. O.; Zwerger, W.; Zoller, P.

    2002-01-01

    We investigate the physical properties of quasi-1D quantum gases of fermion atoms confined in harmonic traps. Using the fact that for a homogeneous gas, the low energy properties are exactly described by a Luttinger model, we analyze the nature and manifestations of the spin-charge separation. Finally we discuss the necessary physical conditions and experimental limitations confronting possible experimental implementations.

  12. Microscopic dynamics of charge separation at the aqueous electrochemical interface.

    Science.gov (United States)

    Kattirtzi, John A; Limmer, David T; Willard, Adam P

    2017-12-19

    We have used molecular simulation and methods of importance sampling to study the thermodynamics and kinetics of ionic charge separation at a liquid water-metal interface. We have considered this process using canonical examples of two different classes of ions: a simple alkali-halide pair, Na + I - , or classical ions, and the products of water autoionization, H 3 O + OH - , or water ions. We find that for both ion classes, the microscopic mechanism of charge separation, including water's collective role in the process, is conserved between the bulk liquid and the electrode interface. However, the thermodynamic and kinetic details of the process differ between these two environments in a way that depends on ion type. In the case of the classical ion pairs, a higher free-energy barrier to charge separation and a smaller flux over that barrier at the interface result in a rate of dissociation that is 40 times slower relative to the bulk. For water ions, a slightly higher free-energy barrier is offset by a higher flux over the barrier from longer lived hydrogen-bonding patterns at the interface, resulting in a rate of association that is similar both at and away from the interface. We find that these differences in rates and stabilities of charge separation are due to the altered ability of water to solvate and reorganize in the vicinity of the metal interface.

  13. Ultrafast photoinduced charge separation in metal-semiconductor nanohybrids.

    Science.gov (United States)

    Mongin, Denis; Shaviv, Ehud; Maioli, Paolo; Crut, Aurélien; Banin, Uri; Del Fatti, Natalia; Vallée, Fabrice

    2012-08-28

    Hybrid nano-objects formed by two or more disparate materials are among the most promising and versatile nanosystems. A key parameter in their properties is interaction between their components. In this context we have investigated ultrafast charge separation in semiconductor-metal nanohybrids using a model system of gold-tipped CdS nanorods in a matchstick architecture. Experiments are performed using an optical time-resolved pump-probe technique, exciting either the semiconductor or the metal component of the particles, and probing the light-induced change of their optical response. Electron-hole pairs photoexcited in the semiconductor part of the nanohybrids are shown to undergo rapid charge separation with the electron transferred to the metal part on a sub-20 fs time scale. This ultrafast gold charging leads to a transient red-shift and broadening of the metal surface plasmon resonance, in agreement with results for free clusters but in contrast to observation for static charging of gold nanoparticles in liquid environments. Quantitative comparison with a theoretical model is in excellent agreement with the experimental results, confirming photoexcitation of one electron-hole pair per nanohybrid followed by ultrafast charge separation. The results also point to the utilization of such metal-semiconductor nanohybrids in light-harvesting applications and in photocatalysis.

  14. Directional Charge Separation in Isolated Organic Semiconductor Crystalline Nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, Michael; Labastide, Joelle; Bond-Thompson, Hilary; Briseno, Alejandro; Collela, Nicolas

    2017-03-01

    In the conventional view of organic photovoltaics (OPV), localized electronic excitations (excitons) formed in the active layer are transported by random 3D diffusion to an interface where charge separation and extraction take place. Because radiative de-excitation is usually strongly allowed in organic semiconductors, efficient charge separation requires high exciton mobility, with much of the diffusive motion ‘wasted’ in directions that don’t result in an interface encounter. Our research efforts are focused on ways to enforce a preferred directionality in energy and/or charge transport using ordered crystalline nanowires in which the intermolecular interactions that facilitate transport along, for example, the pi-stacking axis, can be made several orders of magnitude stronger than those in a transverse direction. The results presented in our recent work (Nature Communications) is a first step towards realizing the goal of directional control of both energy transport and charge separation, where excitons shared between adjacent molecules dissociate exclusively along the pi-stacking direction.

  15. Plasma expansion into vacuum with charge separation effect

    International Nuclear Information System (INIS)

    Murakami, Masakatsu

    2008-01-01

    Plasma expansion into vacuum and resultant ion acceleration are studied theoretically. A new self-similar solution is found to describe free expansion of a finite plasma mass into vacuum with a full account of charge separation effects. It is argued that the normalized plasma size Λ R/λ D plays the dominant role in determining the whole ion energy spectrum and thus the maximum ion kinetic energy, where R and λ D are the plasma scale length and the Debye length, respectively. The analytical model is compared with experiments to show excellent agreement

  16. Charge separation in contact systems with CdSe quantum dot layers

    International Nuclear Information System (INIS)

    Zillner, Elisabeth Franziska

    2013-01-01

    (recombination). The values of QD-ITO distance and trap density, determined with the simulation were consistent with transmission electron microscopy and photoluminescence measurements. The separation and diffusion of charge carriers was limited due to trapping of charge carriers. Smaller interparticle distances led to faster decays in CdSe QD monolayers. However the increase of traps, which resulted in a slower decay dominated and led to longer decay times of SPV transients of modified CdSe QD layers. By deposition of CdSe QDs on CdS a heterojunction was created. The CdS layer served as acceptor for electrons excited in CdSe QDs. Furthermore a CdSe QD/CdTe nanoparticle heterojunction was realized by successive electrophoretic deposition. CdSe QDs acted as electron acceptors, whereas CdTe nanoparticles acted as electron donors. Charge separation was dominated by the CdSe QD/CdTe nanoparticle interphase, as inverted layer stacking of CdSe QDs and CdTe nanoparticles gave an inverted SPV signal.

  17. Charge separation in contact systems with CdSe quantum dot layers

    Energy Technology Data Exchange (ETDEWEB)

    Zillner, Elisabeth Franziska

    2013-03-06

    (recombination). The values of QD-ITO distance and trap density, determined with the simulation were consistent with transmission electron microscopy and photoluminescence measurements. The separation and diffusion of charge carriers was limited due to trapping of charge carriers. Smaller interparticle distances led to faster decays in CdSe QD monolayers. However the increase of traps, which resulted in a slower decay dominated and led to longer decay times of SPV transients of modified CdSe QD layers. By deposition of CdSe QDs on CdS a heterojunction was created. The CdS layer served as acceptor for electrons excited in CdSe QDs. Furthermore a CdSe QD/CdTe nanoparticle heterojunction was realized by successive electrophoretic deposition. CdSe QDs acted as electron acceptors, whereas CdTe nanoparticles acted as electron donors. Charge separation was dominated by the CdSe QD/CdTe nanoparticle interphase, as inverted layer stacking of CdSe QDs and CdTe nanoparticles gave an inverted SPV signal.

  18. The laser proton acceleration in the strong charge separation regime

    International Nuclear Information System (INIS)

    Nishiuchi, M.; Fukumi, A.; Daido, H.; Li, Z.; Sagisaka, A.; Ogura, K.; Orimo, S.; Kado, M.; Hayashi, Y.; Mori, M.; Bulanov, S.V.; Esirkepov, T.; Nemoto, K.; Oishi, Y.; Nayuki, T.; Fujii, T.; Noda, A.; Iwashita, Y.; Shirai, T.; Nakamura, S.

    2006-01-01

    We report the experimental results of proton acceleration as well as the simple one-dimensional model which explains our experimental data. The proton acceleration experiment is carried out with a TW short pulse laser irradiated on a tantalum thin-foil target (3 μm thickness) with an intensity of ∼3x10 18 Wcm -2 . Accelerated protons exhibit a typical energy spectrum with two quasi-Maxwellian components with a high energy cut-off. We can successfully explain the higher energy part as well as the cut off energy of the proton spectrum with the simple-one-dimensional model based on the strong charge separation regime, which is the extension of the model proposed originally by [M. Passoni et al., Phys. Rev. E 69 (2004) 026411

  19. Theory and application of dual-transistor charge separation analysis

    International Nuclear Information System (INIS)

    Fleetwood, D.M.; Schwank, J.R.; Winokur, P.S.; Sexton, F.W.; Shaneyfelt, M.R.

    1989-01-01

    The authors describe a dual-transistor charge separation method to evaluate the radiation response of MOS transistors. This method requires that n- and p-channel transistors with identically processed oxides be irradiated under identical conditions at the same oxide electric fields. Combining features of single-transistor midgap and mobility methods, the authors show how one may determine threshold voltage shifts due to oxide-trapped and interface-trapped charge from standard threshold voltage and mobility measurements. These measurements can be made at currents 2-5 orders of magnitude higher than those required for midgap, subthreshold slope, and charge-pumping methods. The dual-transistor method contains no adjustable parameters, and includes an internal self-consistency check. The accuracy of the method is verified by comparison to midgap, subthreshold slope, and charge-pumping methods for several MOS processes and technologies

  20. Plasmon-induced charge separation: chemistry and wide applications.

    Science.gov (United States)

    Tatsuma, Tetsu; Nishi, Hiroyasu; Ishida, Takuya

    2017-05-01

    Recent development of nanoplasmonics has stimulated chemists to utilize plasmonic nanomaterials for efficient and distinctive photochemical applications, and physicists to boldly go inside the "wet" chemistry world. The discovery of plasmon-induced charge separation (PICS) has even accelerated these trends. On the other hand, some confusion is found in discussions about PICS. In this perspective, we focus on differences between PICS and some other phenomena such as co-catalysis effect and plasmonic nanoantenna effect. In addition, materials and nanostructures suitable for PICS are shown, and characteristics and features unique to PICS are documented. Although it is well known that PICS has been applied to photovoltaics and photocatalysis, here light is shed on other applications that take better advantage of PICS, such as chemical sensing and biosensing, various photochromisms, photoswitchable functionalities and nanoscale photofabrication.

  1. Laser-induced charge separation in organic nanofibers

    DEFF Research Database (Denmark)

    Tavares, Luciana; Behn, Dino; Kjelstrup-Hansen, Jakob

    Organic semiconductors have unique properties that can be tailored via synthetic chemistry for specific applications, which combined with their low price and straight-forward processing over large areas make them interesting materials for future devices. Certain oligomers can self-assemble into c......Organic semiconductors have unique properties that can be tailored via synthetic chemistry for specific applications, which combined with their low price and straight-forward processing over large areas make them interesting materials for future devices. Certain oligomers can self......-assemble into crystalline nanofibers by vapor deposition onto muscovite mica substrates, and we have recently shown that such nanofibers can be transferred to different substrates by roll-printing and used as the active material in e.g. organic field-effect transistors (OFETs), organic light-emitting transistors (OLETs......), and organic phototransistors (OPTs). However, several device-related issues incl. charge-separation and local band structure remain poorly understood. In this work, we use electrostatic force microscopy (EFM) combined with optical microscopy to study the local surface charge of an individual organic nanofiber...

  2. Spin-Charge Separation in Finite Length Metallic Carbon Nanotubes

    KAUST Repository

    Zhang, Yongyou

    2017-10-17

    Using time-dependent density functional theory, we study the optical excitations in finite length carbon nanotubes. Evidence of spin-charge separation is given in the spacetime domain. We demonstrate that the charge density wave is due to collective excitations of electron singlets, while the accompanying spin density wave is due to those of electron triplets. The Tomonaga–Luttinger liquid parameter and density–density interaction are extrapolated from the first-principles excitation energies. We show that the density–density interaction increases with the length of the nanotube. The singlet and triplet excitation energies, on the other hand, decrease for increasing length of the nanotube. Their ratio is used to establish a first-principles approach for deriving the Tomonaga–Luttinger parameter (in excellent agreement with experimental data). Time evolution analysis of the charge and spin line densities evidences that the charge and spin density waves are elementary excitations of metallic carbon nanotubes. Their dynamics show no dependence on each other.

  3. How exciton-vibrational coherences control charge separation in the photosystem II reaction center.

    Science.gov (United States)

    Novoderezhkin, Vladimir I; Romero, Elisabet; van Grondelle, Rienk

    2015-12-14

    In photosynthesis absorbed sun light produces collective excitations (excitons) that form a coherent superposition of electronic and vibrational states of the individual pigments. Two-dimensional (2D) electronic spectroscopy allows a visualization of how these coherences are involved in the primary processes of energy and charge transfer. Based on quantitative modeling we identify the exciton-vibrational coherences observed in 2D photon echo of the photosystem II reaction center (PSII-RC). We find that the vibrations resonant with the exciton splittings can modify the delocalization of the exciton states and produce additional states, thus promoting directed energy transfer and allowing a switch between the two charge separation pathways. We conclude that the coincidence of the frequencies of the most intense vibrations with the splittings within the manifold of exciton and charge-transfer states in the PSII-RC is not occurring by chance, but reflects a fundamental principle of how energy conversion in photosynthesis was optimized.

  4. Charge separation and transfer in hybrid type II tunneling structures of CdTe and CdSe nanocrystals

    International Nuclear Information System (INIS)

    Gross, Dieter Konrad Michael

    2013-01-01

    Closely packed nanocrystal systems have been investigated in this thesis with respect to charge separation by charge carrier tunneling. Clustered and layered samples have been analyzed using PL-measurements and SPV-methods. The most important findings are reviewed in the following. A short outlook is also provided for potential further aspects and application of the presented results. The main purpose of this thesis was to find and quantify electronic tunneling transfer in closely packed self-assembled nanocrystal structures presenting quantum mechanical barriers of about 1 nm width. We successfully used hybrid assemblies of CdTe and CdSe nanocrystals where the expected type II alignment between CdTe and CdSe typically leads to a concentration of electrons in CdSe and holes in CdTe nanocrystals. We were able to prove the charge selectivity of the CdTe-CdSe nanocrystal interface which induces charge separation. We mainly investigated the effects related to the electron transfer from CdTe to CdSe nanocrystals. Closely packing was achieved by two independent methods: the disordered colloidal clustering in solution and the layered assembly on dry glass substrates. Both methods lead to an inter-particle distance of about 1 nm of mainly organic material which acts as a tunneling barrier. PL-spectroscopy was applied. The PL-quenching of the CdTe nanocrystals in hybrid assemblies indicates charge separation by electron transfer from CdTe to CdSe nanocrystals. A maximum quenching rate of up to 1/100 ps was measured leading to a significant global PL-quenching of up to about 70 % for the CdTe nanocrystals. It was shown that charge separation dynamics compete with energy transfer dynamics and that charge separation typically dominates. The quantum confinement effect was used to tune the energetic offset between the CdTe and CdSe nanocrystals. We thus observe a correlation of PL-quenching and offset of the energy states for the electron transfer. The investigated PL

  5. Charge separation and transfer in hybrid type II tunneling structures of CdTe and CdSe nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Gross, Dieter Konrad Michael

    2013-11-08

    Closely packed nanocrystal systems have been investigated in this thesis with respect to charge separation by charge carrier tunneling. Clustered and layered samples have been analyzed using PL-measurements and SPV-methods. The most important findings are reviewed in the following. A short outlook is also provided for potential further aspects and application of the presented results. The main purpose of this thesis was to find and quantify electronic tunneling transfer in closely packed self-assembled nanocrystal structures presenting quantum mechanical barriers of about 1 nm width. We successfully used hybrid assemblies of CdTe and CdSe nanocrystals where the expected type II alignment between CdTe and CdSe typically leads to a concentration of electrons in CdSe and holes in CdTe nanocrystals. We were able to prove the charge selectivity of the CdTe-CdSe nanocrystal interface which induces charge separation. We mainly investigated the effects related to the electron transfer from CdTe to CdSe nanocrystals. Closely packing was achieved by two independent methods: the disordered colloidal clustering in solution and the layered assembly on dry glass substrates. Both methods lead to an inter-particle distance of about 1 nm of mainly organic material which acts as a tunneling barrier. PL-spectroscopy was applied. The PL-quenching of the CdTe nanocrystals in hybrid assemblies indicates charge separation by electron transfer from CdTe to CdSe nanocrystals. A maximum quenching rate of up to 1/100 ps was measured leading to a significant global PL-quenching of up to about 70 % for the CdTe nanocrystals. It was shown that charge separation dynamics compete with energy transfer dynamics and that charge separation typically dominates. The quantum confinement effect was used to tune the energetic offset between the CdTe and CdSe nanocrystals. We thus observe a correlation of PL-quenching and offset of the energy states for the electron transfer. The investigated PL

  6. Promising Strategy To Improve Charge Separation in Organic Photovoltaics : Installing Permanent Dipoles in PCBM Analogues

    NARCIS (Netherlands)

    de Gier, Hilde D.; Jahani, Fatemeh; Broer, Ria; Hummelen, Jan C.; Havenith, Remco W. A.

    2016-01-01

    A multidisciplinary approach involving organic synthesis and theoretical chemistry was applied to investigate a promising strategy to improve charge separation in organic photovoltaics: installing permanent dipoles in fullerene derivatives. First, a PCBM analogue with a permanent dipole in the side

  7. On the Molecular Origin of Charge Separation at the Donor-Acceptor Interface

    KAUST Repository

    Sini, Gjergji; Schubert, Marcel; Risko, Chad; Roland, Steffen; Lee, Olivia P.; Chen, Zhihua; Richter, Thomas V.; Dolfen, Daniel; Coropceanu, Veaceslav; Ludwigs, Sabine; Scherf, Ullrich; Facchetti, Antonio; Frechet, Jean; Neher, Dieter

    2018-01-01

    and theoretical approach is used to understand the intimate mechanisms by which molecular structure contributes to exciton dissociation, charge separation, and charge recombination at the donor–acceptor (D–A) interface. Model systems comprised of polythiophene

  8. Strategies for Efficient Charge Separation and Transfer in Artificial Photosynthesis of Solar Fuels.

    Science.gov (United States)

    Xu, Yuxing; Li, Ailong; Yao, Tingting; Ma, Changtong; Zhang, Xianwen; Shah, Jafar Hussain; Han, Hongxian

    2017-11-23

    Converting sunlight to solar fuels by artificial photosynthesis is an innovative science and technology for renewable energy. Light harvesting, photogenerated charge separation and transfer (CST), and catalytic reactions are the three primary steps in the processes involved in the conversion of solar energy to chemical energy (SE-CE). Among the processes, CST is the key "energy pump and delivery" step in determining the overall solar-energy conversion efficiency. Efficient CST is always high priority in designing and assembling artificial photosynthesis systems for solar-fuel production. This Review not only introduces the fundamental strategies for CST but also the combinatory application of these strategies to five types of the most-investigated semiconductor-based artificial photosynthesis systems: particulate, Z-scheme, hybrid, photoelectrochemical, and photovoltaics-assisted systems. We show that artificial photosynthesis systems with high SE-CE efficiency can be rationally designed and constructed through combinatory application of these strategies, setting a promising blueprint for the future of solar fuels. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Impact of charge-transfer excitons in regioregular polythiophene on the charge separation at polythiophene-fullerene heterojunctions

    Science.gov (United States)

    Polkehn, M.; Tamura, H.; Burghardt, I.

    2018-01-01

    This study addresses the mechanism of ultrafast charge separation in regioregular oligothiophene-fullerene assemblies representative of poly-3-hexylthiophene (P3HT)-[6,6]-phenyl-C61 butyric acid methyl ester (PCBM) heterojunctions, with special emphasis on the inclusion of charge transfer excitons in the oligothiophene phase. The formation of polaronic inter-chain charge separated species in highly ordered oligothiophene has been demonstrated in recent experiments and could have a significant impact on the net charge transfer to the fullerene acceptor. The present approach combines a first-principles parametrized multi-site Hamiltonian, based on time-dependent density functional theory calculations, with accurate quantum dynamics simulations using the multi-layer multi-configuration time-dependent Hartree method. Quantum dynamical studies are carried out for up to 182 electronic states and 112 phonon modes. The present analysis follows up on our previous study of (Huix-Rotllant et al 2015 J. Phys. Chem. Lett. 6 1702) and significantly expands the scope of this analysis by including the dynamical role of charge transfer excitons. Our investigation highlights the pronounced mixing of photogenerated Frenkel excitons with charge transfer excitons in the oligothiophene domain, and the opening of new transfer channels due the creation of such charge-separated species. As a result, it turns out that the interfacial donor/acceptor charge transfer state can be largely circumvented due to the presence of charge transfer excitons. However, the latter states in turn act as a trap, such that the free carrier yield observed on ultrafast time scales is tangibly reduced. The present analysis underscores the complexity of the transfer pathways at P3HT-PCBM type junctions.

  10. Charge separation and transfer in hybrid type II tunneling structures of CdTe and CdSe nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Gross, Dieter Konrad Michael

    2013-11-08

    Closely packed nanocrystal systems have been investigated in this thesis with respect to charge separation by charge carrier tunneling. Clustered and layered samples have been analyzed using PL-measurements and SPV-methods. The most important findings are reviewed in the following. A short outlook is also provided for potential further aspects and application of the presented results. The main purpose of this thesis was to find and quantify electronic tunneling transfer in closely packed self-assembled nanocrystal structures presenting quantum mechanical barriers of about 1 nm width. We successfully used hybrid assemblies of CdTe and CdSe nanocrystals where the expected type II alignment between CdTe and CdSe typically leads to a concentration of electrons in CdSe and holes in CdTe nanocrystals. We were able to prove the charge selectivity of the CdTe-CdSe nanocrystal interface which induces charge separation. We mainly investigated the effects related to the electron transfer from CdTe to CdSe nanocrystals. Closely packing was achieved by two independent methods: the disordered colloidal clustering in solution and the layered assembly on dry glass substrates. Both methods lead to an inter-particle distance of about 1 nm of mainly organic material which acts as a tunneling barrier. PL-spectroscopy was applied. The PL-quenching of the CdTe nanocrystals in hybrid assemblies indicates charge separation by electron transfer from CdTe to CdSe nanocrystals. A maximum quenching rate of up to 1/100 ps was measured leading to a significant global PL-quenching of up to about 70 % for the CdTe nanocrystals. It was shown that charge separation dynamics compete with energy transfer dynamics and that charge separation typically dominates. The quantum confinement effect was used to tune the energetic offset between the CdTe and CdSe nanocrystals. We thus observe a correlation of PL-quenching and offset of the energy states for the electron transfer. The investigated PL

  11. Synthetic system mimicking the energy transfer and charge separation of natural photosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Gust, D.; Moore, T.A.

    1985-05-01

    A synthetic molecular triad consisting of a porphyrin P linked to both a quinone Q and a carotenoid polyene C has been prepared as a mimic of natural photosynthesis for solar energy conversion purposes. Laser flash excitation of the porphyrin moiety yields a charge-separated state Csup(+.)-P-Qsup(-.) within 100 ps with a quantum yield of more than 0.25. This charge-separated state has a lifetime on the microsecond time scale in suitable solvents. The triad also models photosynthetic antenna function and photoprotection from singlet oxygen damge. The successful biomimicry of photosynthetic charge separation is in part the result of multistep electron transfers which rapidly separate the charges and leave the system at high potential, but with a considerable barrier to recombination.

  12. Charge separation at nanoscale interfaces: energy-level alignment including two-quasiparticle interactions.

    Science.gov (United States)

    Li, Huashan; Lin, Zhibin; Lusk, Mark T; Wu, Zhigang

    2014-10-21

    The universal and fundamental criteria for charge separation at interfaces involving nanoscale materials are investigated. In addition to the single-quasiparticle excitation, all the two-quasiparticle effects including exciton binding, Coulomb stabilization, and exciton transfer are considered, which play critical roles on nanoscale interfaces for optoelectronic applications. We propose a scheme allowing adding these two-quasiparticle interactions on top of the single-quasiparticle energy level alignment for determining and illuminating charge separation at nanoscale interfaces. Employing the many-body perturbation theory based on Green's functions, we quantitatively demonstrate that neglecting or simplifying these crucial two-quasiparticle interactions using less accurate methods is likely to predict qualitatively incorrect charge separation behaviors at nanoscale interfaces where quantum confinement dominates.

  13. Light dependence of quantum yields for PSII charge separation and oxygen evolution in eucaryotic algae

    NARCIS (Netherlands)

    Flameling, I.A.; Kromkamp, J.C.

    1998-01-01

    Quantum yields of photosystem II (PSII) charge separation (Phi(P)) and oxygen production (Phi(O2)) were determined by simultaneous measurements of oxygen production and variable fluorescence in four different aquatic microalgae representing three different taxonomic groups: the freshwater alga

  14. Picosecond absorption studies of photoinduced charge separation in polyelectrolyte bound aromatic chromophores

    Science.gov (United States)

    Shand, M. A.; Rodgers, M. A. J.; Webber, S. E.

    1991-02-01

    Picosecond absorption studies of photoinduced electron transfer between aromatic chromophores bound to polymethacrylic acid (P) and methylviologen (MV 2+ have been carried out in aqueous solution. The diphenylanthracene copolymer/viologen system at pH 2.8 shows the corresponding redox products DPA + rad and MV + rad arising from the singlet state of DPA with a forward rate constant of electron transfer of 2.6 × 10 9 s -1. At pH 9.0 the quenching of the S 1 state of DPA occurs with no charge separated products being observed. The pyrene copolymer shows no evidence of charge separated products at any pH in the range 2.8-9.0. It is proposed that the differences in the radical pair kinetics arise from differences in the degree of binding of the ground state complexes formed by the donor and acceptor species.

  15. Charge separation technique for metal-oxide-silicon capacitors in the presence of hydrogen deactivated dopants

    International Nuclear Information System (INIS)

    Witczak, Steven C.; Winokur, Peter S.; Lacoe, Ronald C.; Mayer, Donald C.

    2000-01-01

    An improved charge separation technique for metal-oxide-silicon (MOS) capacitors is presented which accounts for the deactivation of substrate dopants by hydrogen at elevated irradiation temperatures or small irradiation biases. Using high-frequency capacitance-voltage (C-V) measurements, radiation-induced inversion voltage shifts are separated into components due to oxide trapped charge, interface traps and deactivated dopants, where the latter is computed from a reduction in Si capacitance. In the limit of no radiation-induced dopant deactivation, this approach reduces to the standard midgap charge separation technique used widely for the analysis of room-temperature irradiations. The technique is demonstrated on a p-type MOS capacitor irradiated with 60 Co γ-rays at 100 C and zero bias, where the dopant deactivation is significant

  16. Describing long-range charge-separation processes with subsystem density-functional theory

    Energy Technology Data Exchange (ETDEWEB)

    Solovyeva, Alisa; Neugebauer, Johannes, E-mail: j.neugebauer@uni-muenster.de [Theoretische Organische Chemie, Organisch-Chemisches Institut and Center for Multiscale Theory and Simulation, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster (Germany); Pavanello, Michele, E-mail: m.pavanello@rutgers.edu [Department of Chemistry, Rutgers University, 73 Warren St., Newark, New Jersey 07102 (United States)

    2014-04-28

    Long-range charge-transfer processes in extended systems are difficult to describe with quantum chemical methods. In particular, cost-effective (non-hybrid) approximations within time-dependent density functional theory (DFT) are not applicable unless special precautions are taken. Here, we show that the efficient subsystem DFT can be employed as a constrained DFT variant to describe the energetics of long-range charge-separation processes. A formal analysis of the energy components in subsystem DFT for such excitation energies is presented, which demonstrates that both the distance dependence and the long-range limit are correctly described. In addition, electronic couplings for these processes as needed for rate constants in Marcus theory can be obtained from this method. It is shown that the electronic structure of charge-separated states constructed by a positively charged subsystem interacting with a negatively charged one is difficult to converge — charge leaking from the negative subsystem to the positive one can occur. This problem is related to the delocalization error in DFT and can be overcome with asymptotically correct exchange–correlation (XC) potentials or XC potentials including a sufficiently large amount of exact exchange. We also outline an approximate way to obtain charge-transfer couplings between locally excited and charge-separated states.

  17. Describing long-range charge-separation processes with subsystem density-functional theory

    International Nuclear Information System (INIS)

    Solovyeva, Alisa; Neugebauer, Johannes; Pavanello, Michele

    2014-01-01

    Long-range charge-transfer processes in extended systems are difficult to describe with quantum chemical methods. In particular, cost-effective (non-hybrid) approximations within time-dependent density functional theory (DFT) are not applicable unless special precautions are taken. Here, we show that the efficient subsystem DFT can be employed as a constrained DFT variant to describe the energetics of long-range charge-separation processes. A formal analysis of the energy components in subsystem DFT for such excitation energies is presented, which demonstrates that both the distance dependence and the long-range limit are correctly described. In addition, electronic couplings for these processes as needed for rate constants in Marcus theory can be obtained from this method. It is shown that the electronic structure of charge-separated states constructed by a positively charged subsystem interacting with a negatively charged one is difficult to converge — charge leaking from the negative subsystem to the positive one can occur. This problem is related to the delocalization error in DFT and can be overcome with asymptotically correct exchange–correlation (XC) potentials or XC potentials including a sufficiently large amount of exact exchange. We also outline an approximate way to obtain charge-transfer couplings between locally excited and charge-separated states

  18. Photoinduced charge separation at polymer-fullerene interfaces of BHJ solar cells (Conference Presentation)

    Science.gov (United States)

    Poluektov, Oleg G.; Niklas, Jens; Mardis, Kristy

    2016-09-01

    While photovoltaic cells are highly promising man-made devices for direct solar energy utilization, a number of fundamental questions about how the organic bulk heterojunction cell enables efficient long-lived and long-range charge separation remain unanswered. These questions were address by employing an advanced suite of EPR spectroscopy in combination with DFT calculations to study mechanism of charge separation at the polymer-fullerene interfaces of photo-active BHJ. Observed charge delocalization in BHJ upon photoinduced ET is analogous to that in organic donor-acceptor material. This is an efficient mechanism of charge stabilization in photosynthetic assemblies. Time-resolved EPR spectra show a strong polarization pattern for all polymer-fullerene blends under study, which is caused by non-Boltzmann population of the electron spin energy levels in the radical pairs. The first observation of this phenomenon was reported in natural and artificial photosynthetic assemblies, and comparison with these systems allows us to better understand charge separation processes in OPVs. The spectral analysis presented here, in combination with DFT calculations, shows that CS processes in OPV materials are similar to that in organic photosynthetic systems. This work was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, under Contract DE-AC02-06CH11357 at Argonne National Laboratory.

  19. Charge separation at disordered semiconductor heterojunctions from random walk numerical simulations.

    Science.gov (United States)

    Mandujano-Ramírez, Humberto J; González-Vázquez, José P; Oskam, Gerko; Dittrich, Thomas; Garcia-Belmonte, Germa; Mora-Seró, Iván; Bisquert, Juan; Anta, Juan A

    2014-03-07

    Many recent advances in novel solar cell technologies are based on charge separation in disordered semiconductor heterojunctions. In this work we use the Random Walk Numerical Simulation (RWNS) method to model the dynamics of electrons and holes in two disordered semiconductors in contact. Miller-Abrahams hopping rates and a tunnelling distance-dependent electron-hole annihilation mechanism are used to model transport and recombination, respectively. To test the validity of the model, three numerical "experiments" have been devised: (1) in the absence of constant illumination, charge separation has been quantified by computing surface photovoltage (SPV) transients. (2) By applying a continuous generation of electron-hole pairs, the model can be used to simulate a solar cell under steady-state conditions. This has been exploited to calculate open-circuit voltages and recombination currents for an archetypical bulk heterojunction solar cell (BHJ). (3) The calculations have been extended to nanostructured solar cells with inorganic sensitizers to study, specifically, non-ideality in the recombination rate. The RWNS model in combination with exponential disorder and an activated tunnelling mechanism for transport and recombination is shown to reproduce correctly charge separation parameters in these three "experiments". This provides a theoretical basis to study relevant features of novel solar cell technologies.

  20. Gradient Self-Doped CuBi2O4 with Highly Improved Charge Separation Efficiency.

    Science.gov (United States)

    Wang, Fuxian; Septina, Wilman; Chemseddine, Abdelkrim; Abdi, Fatwa F; Friedrich, Dennis; Bogdanoff, Peter; van de Krol, Roel; Tilley, S David; Berglund, Sean P

    2017-10-25

    A new strategy of using forward gradient self-doping to improve the charge separation efficiency in metal oxide photoelectrodes is proposed. Gradient self-doped CuBi 2 O 4 photocathodes are prepared with forward and reverse gradients in copper vacancies using a two-step, diffusion-assisted spray pyrolysis process. Decreasing the Cu/Bi ratio of the CuBi 2 O 4 photocathodes introduces Cu vacancies that increase the carrier (hole) concentration and lowers the Fermi level, as evidenced by a shift in the flat band toward more positive potentials. Thus, a gradient in Cu vacancies leads to an internal electric field within CuBi 2 O 4 , which can facilitate charge separation. Compared to homogeneous CuBi 2 O 4 photocathodes, CuBi 2 O 4 photocathodes with a forward gradient show highly improved charge separation efficiency and enhanced photoelectrochemical performance for reduction reactions, while CuBi 2 O 4 photocathodes with a reverse gradient show significantly reduced charge separation efficiency and photoelectrochemical performance. The CuBi 2 O 4 photocathodes with a forward gradient produce record AM 1.5 photocurrent densities for CuBi 2 O 4 up to -2.5 mA/cm 2 at 0.6 V vs RHE with H 2 O 2 as an electron scavenger, and they show a charge separation efficiency of 34% for 550 nm light. The gradient self-doping accomplishes this without the introduction of external dopants, and therefore the tetragonal crystal structure and carrier mobility of CuBi 2 O 4 are maintained. Lastly, forward gradient self-doped CuBi 2 O 4 photocathodes are protected with a CdS/TiO 2 heterojunction and coated with Pt as an electrocatalyst. These photocathodes demonstrate photocurrent densities on the order of -1.0 mA/cm 2 at 0.0 V vs RHE and evolve hydrogen with a faradaic efficiency of ∼91%.

  1. Spin Drag and Spin-Charge Separation in Cold Fermi Gases

    International Nuclear Information System (INIS)

    Polini, Marco; Vignale, Giovanni

    2007-01-01

    Low-energy spin and charge excitations of one-dimensional interacting fermions are completely decoupled and propagate with different velocities. These modes, however, can decay due to several possible mechanisms. In this Letter we expose a new facet of spin-charge separation: not only the speeds but also the damping rates of spin and charge excitations are different. While the propagation of long-wavelength charge excitations is essentially ballistic, spin propagation is intrinsically damped and diffusive. We suggest that cold Fermi gases trapped inside a tight atomic waveguide offer the opportunity to measure the spin-drag relaxation rate that controls the broadening of a spin packet

  2. Super spin-charge separation for class A, C and D disorder

    International Nuclear Information System (INIS)

    LeClair, Andre; Robinson, Dean J

    2008-01-01

    We prove versions of super spin-charge separation for all three of the symmetry groups SU(N), Sp(2N) and SO(N) of disordered Dirac fermions in 2 + 1 dimensions, which involve the supercurrent algebras gl(1|1) N ,osp(2|2) -2N and osp(2|2) N respectively. For certain restricted classes of disordered potentials, the latter supercurrent algebra based conformal field theories can arise as non-trivial low energy fixed points. For all cases with such a fixed point, we compute the density of states exponents as a function of N. (fast track communication)

  3. Understanding the free energy barrier and multiple timescale dynamics of charge separation in organic photovoltaic cells.

    Science.gov (United States)

    Yan, Yaming; Song, Linze; Shi, Qiang

    2018-02-28

    By employing several lattice model systems, we investigate the free energy barrier and real-time dynamics of charge separation in organic photovoltaic (OPV) cells. It is found that the combined effects of the external electric field, entropy, and charge delocalization reduce the free energy barrier significantly. The dynamic disorder reduces charge carrier delocalization and results in the increased charge separation barrier, while the effect of static disorder is more complicated. Simulation of the real-time dynamics indicates that the free charge generation process involves multiple time scales, including an ultrafast component within hundreds of femtoseconds, an intermediate component related to the relaxation of the hot charge transfer (CT) state, and a slow component on the time scale of tens of picoseconds from the thermally equilibrated CT state. Effects of hot exciton dissociation as well as its dependence on the energy offset between the Frenkel exciton and the CT state are also analyzed. The current results indicate that only a small energy offset between the band gap and the lowest energy CT state is needed to achieve efficient free charge generation in OPV devices, which agrees with recent experimental findings.

  4. Charge separation and carrier dynamics in donor-acceptor heterojunction photovoltaic systems.

    Science.gov (United States)

    Teuscher, Joël; Brauer, Jan C; Stepanov, Andrey; Solano, Alicia; Boziki, Ariadni; Chergui, Majed; Wolf, Jean-Pierre; Rothlisberger, Ursula; Banerji, Natalie; Moser, Jacques-E

    2017-11-01

    Electron transfer and subsequent charge separation across donor-acceptor heterojunctions remain the most important areas of study in the field of third-generation photovoltaics. In this context, it is particularly important to unravel the dynamics of individual ultrafast processes (such as photoinduced electron transfer, carrier trapping and association, and energy transfer and relaxation), which prevail in materials and at their interfaces. In the frame of the National Center of Competence in Research "Molecular Ultrafast Science and Technology," a research instrument of the Swiss National Science Foundation, several groups active in the field of ultrafast science in Switzerland have applied a number of complementary experimental techniques and computational simulation tools to scrutinize these critical photophysical phenomena. Structural, electronic, and transport properties of the materials and the detailed mechanisms of photoinduced charge separation in dye-sensitized solar cells, conjugated polymer- and small molecule-based organic photovoltaics, and high-efficiency lead halide perovskite solar energy converters have been scrutinized. Results yielded more than thirty research articles, an overview of which is provided here.

  5. On the Molecular Origin of Charge Separation at the Donor-Acceptor Interface

    KAUST Repository

    Sini, Gjergji

    2018-01-22

    Fullerene-based acceptors have dominated organic solar cells for almost two decades. It is only within the last few years that alternative acceptors rival their dominance, introducing much more flexibility in the optoelectronic properties of these material blends. However, a fundamental physical understanding of the processes that drive charge separation at organic heterojunctions is still missing, but urgently needed to direct further material improvements. Here a combined experimental and theoretical approach is used to understand the intimate mechanisms by which molecular structure contributes to exciton dissociation, charge separation, and charge recombination at the donor–acceptor (D–A) interface. Model systems comprised of polythiophene-based donor and rylene diimide-based acceptor polymers are used and a detailed density functional theory (DFT) investigation is performed. The results point to the roles that geometric deformations and direct-contact intermolecular polarization play in establishing a driving force (energy gradient) for the optoelectronic processes taking place at the interface. A substantial impact for this driving force is found to stem from polymer deformations at the interface, a finding that can clearly lead to new design approaches in the development of the next generation of conjugated polymers and small molecules.

  6. Charge separation and carrier dynamics in donor-acceptor heterojunction photovoltaic systems

    Directory of Open Access Journals (Sweden)

    Joël Teuscher

    2017-11-01

    Full Text Available Electron transfer and subsequent charge separation across donor-acceptor heterojunctions remain the most important areas of study in the field of third-generation photovoltaics. In this context, it is particularly important to unravel the dynamics of individual ultrafast processes (such as photoinduced electron transfer, carrier trapping and association, and energy transfer and relaxation, which prevail in materials and at their interfaces. In the frame of the National Center of Competence in Research “Molecular Ultrafast Science and Technology,” a research instrument of the Swiss National Science Foundation, several groups active in the field of ultrafast science in Switzerland have applied a number of complementary experimental techniques and computational simulation tools to scrutinize these critical photophysical phenomena. Structural, electronic, and transport properties of the materials and the detailed mechanisms of photoinduced charge separation in dye-sensitized solar cells, conjugated polymer- and small molecule-based organic photovoltaics, and high-efficiency lead halide perovskite solar energy converters have been scrutinized. Results yielded more than thirty research articles, an overview of which is provided here.

  7. Early bacteriopheophytin reduction in charge separation in reaction centers of Rhodobacter sphaeroides.

    Science.gov (United States)

    Zhu, Jingyi; van Stokkum, Ivo H M; Paparelli, Laura; Jones, Michael R; Groot, Marie Louise

    2013-06-04

    A question at the forefront of biophysical sciences is, to what extent do quantum effects and protein conformational changes play a role in processes such as biological sensing and energy conversion? At the heart of photosynthetic energy transduction lie processes involving ultrafast energy and electron transfers among a small number of tetrapyrrole pigments embedded in the interior of a protein. In the purple bacterial reaction center (RC), a highly efficient ultrafast charge separation takes place between a pair of bacteriochlorophylls: an accessory bacteriochlorophyll (B) and bacteriopheophytin (H). In this work, we applied ultrafast spectroscopy in the visible and near-infrared spectral region to Rhodobacter sphaeroides RCs to accurately track the timing of the electron on BA and HA via the appearance of the BA and HA anion bands. We observed an unexpectedly early rise of the HA⁻ band that challenges the accepted simple picture of stepwise electron transfer with 3 ps and 1 ps time constants. The implications for the mechanism of initial charge separation in bacterial RCs are discussed in terms of a possible adiabatic electron transfer step between BA and HA, and the effect of protein conformation on the electron transfer rate. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  8. Understanding the free energy barrier and multiple timescale dynamics of charge separation in organic photovoltaic cells

    Science.gov (United States)

    Yan, Yaming; Song, Linze; Shi, Qiang

    2018-02-01

    By employing several lattice model systems, we investigate the free energy barrier and real-time dynamics of charge separation in organic photovoltaic (OPV) cells. It is found that the combined effects of the external electric field, entropy, and charge delocalization reduce the free energy barrier significantly. The dynamic disorder reduces charge carrier delocalization and results in the increased charge separation barrier, while the effect of static disorder is more complicated. Simulation of the real-time dynamics indicates that the free charge generation process involves multiple time scales, including an ultrafast component within hundreds of femtoseconds, an intermediate component related to the relaxation of the hot charge transfer (CT) state, and a slow component on the time scale of tens of picoseconds from the thermally equilibrated CT state. Effects of hot exciton dissociation as well as its dependence on the energy offset between the Frenkel exciton and the CT state are also analyzed. The current results indicate that only a small energy offset between the band gap and the lowest energy CT state is needed to achieve efficient free charge generation in OPV devices, which agrees with recent experimental findings.

  9. Theoretical perspectives on electron transfer and charge separation events in photochemical water cleavage systems

    International Nuclear Information System (INIS)

    Kozak, J.J.; Lenoir, P.M.; Musho, M.K.; Tembe, B.L.

    1984-01-01

    We study in this paper the dynamics induced by models for photochemical water cleavage systems, focusing on the spatial and temporal factors influencing electron transfer and charge separation processes in such systems. The reaction-diffusion theory is formulated in full generality and the consequences explored in a number of spatio-temporal regimes, viz. the spatially homogeneous system in the long-time limit (i.e. the steady state for a well-stirred system), the spatially homogeneous system in evolution, and the spatially inhomogeneous system in evolution (where, in the latter study, we consider electron transfer at the cluster surface to be governed by a rate constant that reflects the localized nature of such processes). The results of numerical simulations are presented for all three cases and used to highlight the importance of heterogeneous environments in enhancing the cage escape yield of charge separated species, and to demonstrate the dependence of the hydrogen yield on the localization of electron-transfer processes in the vicinity of the microcatalyst surface

  10. Photoinduced charge separation in a colloidal system of exfoliated layered semiconductor controlled by coexisting aluminosilicate clay.

    Science.gov (United States)

    Nakato, Teruyuki; Yamada, Yoshimi; Miyamoto, Nobuyoshi

    2009-02-05

    We investigated photoinduced charge separation occurring in a multicomponent colloidal system composed of oxide nanosheets of photocatalytically active niobate and photochemically inert clay and electron accepting methylviologen dications (MV2+). The inorganic nanosheets were obtained by exfoliation of layered hexaniobate and hectorite clay. The niobate and clay nanosheets were spatially separated in the colloidally dispersed state, and the MV2+ molecules were selectively adsorbed on the clay platelets. UV irradiation of the colloids led to electron transfer from the niobate nanosheets to the MV2+ molecules adsorbed on clay. The photoinduced electron transfer produced methylviologen radical cations (MV*+), which was characterized by high yield and long lifetime. The yield and stability of the MV*+ species were found to depend strongly on the clay content of the colloid: from a few mol % to approximately 70 mol % of the yield and several tens of minutes to more than 40 h of the lifetime. The contents of the niobate nanosheets and MV2+ molecules and the aging of the colloid also affected the photoinduced charge separation. In the absence of MV2+ molecules in the colloid, UV irradiation induced electron accumulation in the niobate nanosheets. The stability of the electron-accumulated state also depended on the clay content. The variation in the photochemical behavior is discussed in relation to the viscosity of the colloid.

  11. The role of interfacial water layer in atmospherically relevant charge separation

    Science.gov (United States)

    Bhattacharyya, Indrani

    Charge separation at interfaces is important in various atmospheric processes, such as thunderstorms, lightning, and sand storms. It also plays a key role in several industrial processes, including ink-jet printing and electrostatic separation. Surprisingly, little is known about the underlying physics of these charging phenomena. Since thin films of water are ubiquitous, they may play a role in these charge separation processes. This talk will focus on the experimental investigation of the role of a water adlayer in interfacial charging, with relevance to meteorologically important phenomena, such as atmospheric charging due to wave actions on oceans and sand storms. An ocean wave generates thousands of bubbles, which upon bursting produce numerous large jet droplets and small film droplets that are charged. In the 1960s, Blanchard showed that the jet droplets are positively charged. However, the charge on the film droplets was not known. We designed an experiment to exclusively measure the charge on film droplets generated by bubble bursting on pure water and aqueous salt solution surfaces. We measured their charge to be negative and proposed a model where a slight excess of hydroxide ions in the interfacial water layer is responsible for generating these negatively charged droplets. The findings from this research led to a better understanding of the ionic disposition at the air-water interface. Sand particles in a wind-blown sand layer, or 'saltation' layer, become charged due to collisions, so much so, that it can cause lightning. Silica, being hydrophilic, is coated with a water layer even under low-humidity conditions. To investigate the importance of this water adlayer in charging the silica surfaces, we performed experiments to measure the charge on silica surfaces due to contact and collision processes. In case of contact charging, the maximum charge separation occurred at an optimum relative humidity. On the contrary, in collisional charging process, no

  12. Event-shape-engineering study of charge separation in heavy-ion collisions

    Science.gov (United States)

    Wen, Fufang; Bryon, Jacob; Wen, Liwen; Wang, Gang

    2018-01-01

    Recent measurements of charge-dependent azimuthal correlations in high-energy heavy-ion collisions have indicated charge-separation signals perpendicular to the reaction plane, and have been related to the chiral magnetic effect (CME). However, the correlation signal is contaminated with the background caused by the collective motion (flow) of the collision system, and an effective approach is needed to remove the flow background from the correlation. We present a method study with simplified Monte Carlo simulations and a multi-phase transport model, and develop a scheme to reveal the true CME signal via event-shape engineering with the flow vector of the particles of interest. Supported by a grant (DE-FG02-88ER40424) from U.S. Department of Energy, Office of Nuclear Physics

  13. Long-lived charge-separated states in ligand-stabilized silver clusters

    KAUST Repository

    Pelton, Matthew; Tang, Yun; Bakr, Osman; Stellacci, Francesco

    2012-01-01

    Recently developed synthesis methods allow for the production of atomically monodisperse clusters of silver atoms stabilized in solution by aromatic thiol ligands, which exhibit intense absorption peaks throughout the visible and near-IR spectral regions. Here we investigated the time-dependent optical properties of these clusters. We observed two kinetic processes following ultrafast laser excitation of any of the absorption peaks: a rapid decay, with a time constant of 1 ps or less, and a slow decay, with a time constant that can be longer than 300 ns. Both time constants decrease as the polarity of the solvent increases, indicating that the two processes correspond to the formation and recombination, respectively, of a charge-separated state. The long lifetime of this state and the broad optical absorption spectrum mean that the ligand-stabilized silver clusters are promising materials for solar energy harvesting. © 2012 American Chemical Society.

  14. Long-lived charge-separated states in ligand-stabilized silver clusters

    KAUST Repository

    Pelton, Matthew

    2012-07-25

    Recently developed synthesis methods allow for the production of atomically monodisperse clusters of silver atoms stabilized in solution by aromatic thiol ligands, which exhibit intense absorption peaks throughout the visible and near-IR spectral regions. Here we investigated the time-dependent optical properties of these clusters. We observed two kinetic processes following ultrafast laser excitation of any of the absorption peaks: a rapid decay, with a time constant of 1 ps or less, and a slow decay, with a time constant that can be longer than 300 ns. Both time constants decrease as the polarity of the solvent increases, indicating that the two processes correspond to the formation and recombination, respectively, of a charge-separated state. The long lifetime of this state and the broad optical absorption spectrum mean that the ligand-stabilized silver clusters are promising materials for solar energy harvesting. © 2012 American Chemical Society.

  15. Understanding sensitization behavior of lead selenide photoconductive detectors by charge separation model

    International Nuclear Information System (INIS)

    Zhao, Lihua; Qiu, Jijun; Weng, Binbin; Chang, Caleb; Yuan, Zijian; Shi, Zhisheng

    2014-01-01

    We introduce a charge separation model in this work to explain the mechanism of enhanced photoconductivity of polycrystalline lead salt photoconductors. Our results show that this model could clarify the heuristic fabrication processes of such lead salt detectors that were not well understood and often considered mysterious for nearly a century. The improved lifetime and performance of the device, e.g., responsivity, are attributed to the spatial separation of holes and electrons, hence less possibility of carrier recombination. This model shows that in addition to crystal quality the size of crystallites, the depth of outer conversion layer, and doping concentration could all affect detector performance. The simulation results agree well with experimental results and thus offer a very useful tool for further improvement of lead salt detectors. The model was developed with lead salt family of photoconductors in mind, but may well be applicable to a wider class of semiconducting films

  16. On the role of local charge carrier mobility in the charge separation mechanism of organic photovoltaics.

    Science.gov (United States)

    Yoshikawa, Saya; Saeki, Akinori; Saito, Masahiko; Osaka, Itaru; Seki, Shu

    2015-07-21

    Although the charge separation (CS) and transport processes that compete with geminate and non-geminate recombination are commonly regarded as the governing factors of organic photovoltaic (OPV) efficiency, the details of the CS mechanism remain largely unexplored. Here we provide a systematic investigation on the role of local charge carrier mobility in bulk heterojunction films of ten different low-bandgap polymers and polythiophene analogues blended with methanofullerene (PCBM). By correlating with the OPV performances, we demonstrated that the local mobility of the blend measured by time-resolved microwave conductivity is more important for the OPV output than those of the pure polymers. Furthermore, the results revealed two separate trends for crystalline and semi-crystalline polymers. This work offers guidance in the design of high-performance organic solar cells.

  17. Effective charge separation in BiOI/Cu2O composites with enhanced photocatalytic activity

    Science.gov (United States)

    Xia, Yongmei; He, Zuming; Yang, Wei; Tang, Bin; Lu, Yalin; Hu, Kejun; Su, Jiangbin; Li, Xiaoping

    2018-02-01

    Novel BiOI/Cu2O composites were designed and synthesized for the first time by coupling reduction method at low temperature. The samples were characterized by XRD, XPS, SEM, EDS, HRTEM, UV-vis (DRS), FTIR and photo-electro-chemical (PEC) analysis. Results showed that the BiOI/Cu2O composites consisted of three-dimensional (3D), hierarchical cauliflower-like structure composed of BiOI nanosheet and Cu2O cubic submicrometer structure, the composite absorption band broadened, and the absorption intensity in the visible region strengthened. And the composites exhibited an excellent photocatalytic performance, which might be attributed to the improvement of the composite absorption and effective charge separation in BiOI/Cu2O composites. In addition, the possible photocatalytic mechanism was proposed.

  18. Studies on the effect of radio frequency field in a cusp-type charge separation device for direct energy conversion

    International Nuclear Information System (INIS)

    Hamabe, Masaki; Izawa, Hiroaki; Takeno, Hiromasa; Nakamoto, Satoshi; Ichimura, Kazuya; Nakashima, Yousuke

    2016-01-01

    In D- 3 He fusion power generation, an application of direct energy conversion is expected in which separation of charged particles is necessary. A cusp-type direct energy converter (CuspDEC) was proposed as a charge separation device, but its performance was degraded for a high density plasma. The goal of the present study is to establish an additional method to assist charge separation by using a nonlinear effect of a radio frequency (rf) electric field. Following to the previous study, we experimentally examine the effect of an rf field to electron motion in a CuspDEC device. Two ring electrodes were newly installed in a CuspDEC simulator and the current flowing into the electron collector located in the line cusp region was measured on an rf field application. The significant variation in the current was found, and an improvement of the charge separation can be expected by using the phenomenon appropriately. (author)

  19. Studies on the Effect of Radio Frequency Field in a Cusp-Type Charge Separation Device for Direct Energy Conversion

    OpenAIRE

    HAMABE, Masaki; IZAWA, Hiroaki; TAKENO, Hiromasa; NAKAMOTO, Satoshi; ICHIMURA, Kazuya; NAKASHIMA, Yousuke

    2016-01-01

    In D-3He fusion power generation, an application of direct energy conversion is expected in which separation of charged particles is necessary. A cusp-type direct energy converter (CuspDEC) was proposed as a charge separation device, but its performance was degraded for a high density plasma. The goal of the present study is to establish an additional method to assist charge separation by using a nonlinear effect of a radio frequency (rf) electric field. Following to the previous study, we ex...

  20. To the theory of spin-charge separation in one-dimensional correlated electron systems

    International Nuclear Information System (INIS)

    Zvyagin, A.A.

    2004-01-01

    Spin-charge separation is considered to be one of the key properties that distinguish low-dimensional electron systems from others. Three-dimensional correlated electron systems are described by the Fermi liquid theory. There, low-energy excitations (quasiparticles) are reminiscent of noninteracting electrons: They carry charges -e and spins 1/2 . It is believed that for any one-dimensional correlated electron system, low-lying electron excitations carry either only spin and no charge, or only charge without spin. That is why recent experiments looked for such low-lying collective electron excitations, one of which carries only spin, and the other carries only charge. Here we show that despite the fact that for exactly solvable one-dimensional correlated electron models there exist excitations which carry only spin and only charge, in all these models with short-range interactions the low-energy physics is described by low-lying collective excitations, one of which carries both spin and charge

  1. Improved Charge Separation in WO3/CuWO4 Composite Photoanodes for Photoelectrochemical Water Oxidation

    Directory of Open Access Journals (Sweden)

    Danping Wang

    2016-05-01

    Full Text Available Porous tungsten oxide/copper tungstate (WO3/CuWO4 composite thin films were fabricated via a facile in situ conversion method, with a polymer templating strategy. Copper nitrate (Cu(NO32 solution with the copolymer surfactant Pluronic®F-127 (Sigma-Aldrich, St. Louis, MO, USA, generic name, poloxamer 407 was loaded onto WO3 substrates by programmed dip coating, followed by heat treatment in air at 550 °C. The Cu2+ reacted with the WO3 substrate to form the CuWO4 compound. The composite WO3/CuWO4 thin films demonstrated improved photoelectrochemical (PEC performance over WO3 and CuWO4 single phase photoanodes. The factors of light absorption and charge separation efficiency of the composite and two single phase films were investigated to understand the reasons for the PEC enhancement of WO3/CuWO4 composite thin films. The photocurrent was generated from water splitting as confirmed by hydrogen and oxygen gas evolution, and Faradic efficiency was calculated based on the amount of H2 produced. This work provides a low-cost and controllable method to prepare WO3-metal tungstate composite thin films, and also helps to deepen the understanding of charge transfer in WO3/CuWO4 heterojunction.

  2. Doping effect on photoabsorption and charge-separation dynamics in light-harvesting organic molecule

    Directory of Open Access Journals (Sweden)

    Satoshi Ohmura

    2016-01-01

    Full Text Available Using ab-initio theoretical methods, we demonstrate possible enhancement of photo-conversion efficiency of an organic solar cell via intentional doping in molecular graphene-fullerene heterojunction [the hexabenzocoronene (HBC-triethylene glycol (TEG–C60 molecule]. Photoabsorption analysis indicates oxygen substitution into HBC leads to an extension of the spectra up to an infrared regime. A quantum-mechanical molecular dynamics simulation incorporating nonadiabatic electronic transitions reveals that a dissociated charge state (D+ and A- in the O-doped system is more stable than the pristine case due to the presence of an effective barrier by the TEG HOMO/LUMO level. We also find that oxygen doping in HBC enhances the intermolecular carrier mobility after charge separation. On the other hand, the pristine molecule undergoes rapid recombination between donor and acceptor charges at the interface. These analyses suggest that the graphene oxidation opens a new window in the application of organic super-molecules to solar cells.

  3. Hydrodynamics with chiral anomaly and charge separation in relativistic heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Yi, E-mail: yyin@bnl.gov [Physics Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Liao, Jinfeng, E-mail: liaoji@indiana.edu [Physics Department and Center for Exploration of Energy and Matter, Indiana University, 2401 N Milo B. Sampson Lane, Bloomington, IN 47408 (United States); RIKEN BNL Research Center, Bldg. 510A, Brookhaven National Laboratory, Upton, NY 11973 (United States)

    2016-05-10

    Matter with chiral fermions is microscopically described by theory with quantum anomaly and macroscopically described (at low energy) by anomalous hydrodynamics. For such systems in the presence of external magnetic field and chirality imbalance, a charge current is generated along the magnetic field direction — a phenomenon known as the Chiral Magnetic Effect (CME). The quark–gluon plasma created in relativistic heavy ion collisions provides an (approximate) example, for which the CME predicts a charge separation perpendicular to the collisional reaction plane. Charge correlation measurements designed for the search of such signal have been done at RHIC and the LHC for which the interpretations, however, remain unclear due to contamination by background effects that are collective flow driven, theoretically poorly constrained, and experimentally hard to separate. Using anomalous (and viscous) hydrodynamic simulations, we make a first attempt at quantifying contributions to observed charge correlations from both CME and background effects in one and same framework. The implications for the search of CME are discussed.

  4. Interfacial charge separation and photovoltaic efficiency in Fe(ii)-carbene sensitized solar cells.

    Science.gov (United States)

    Pastore, Mariachiara; Duchanois, Thibaut; Liu, Li; Monari, Antonio; Assfeld, Xavier; Haacke, Stefan; Gros, Philippe C

    2016-10-12

    The first combined theoretical and photovoltaic characterization of both homoleptic and heteroleptic Fe(ii)-carbene sensitized photoanodes in working dye sensitized solar cells (DSSCs) has been performed. Three new heteroleptic Fe(ii)-NHC dye sensitizers have been synthesized, characterized and tested. Despite an improved interfacial charge separation in comparison to the homoleptic compounds, the heteroleptic complexes did not show boosted photovoltaic performances. The ab initio quantitative analysis of the interfacial electron and hole transfers and the measured photovoltaic data clearly evidenced fast recombination reactions for heteroleptics, even associated with un unfavorable directional electron flow, and hence slower injection rates, in the case of homoleptics. Notably, quantum mechanics calculations revealed that deprotonation of the not anchored carboxylic function in the homoleptic complex can effectively accelerate the electron injection rate and completely suppress the electron recombination to the oxidized dye. This result suggests that introduction of strong electron-donating substituents on the not-anchored carbene ligand in heteroleptic complexes, in such a way of mimicking the electronic effects of the carboxylate functionality, should yield markedly improved interfacial charge generation properties. The present results, providing for the first time a detailed understanding of the interfacial electron transfers and photovoltaic characterization in Fe(ii)-carbene sensitized solar cells, open the way to a rational molecular engineering of efficient iron-based dyes for photoelectrochemical applications.

  5. Doping effect on photoabsorption and charge-separation dynamics in light-harvesting organic molecule

    Energy Technology Data Exchange (ETDEWEB)

    Ohmura, Satoshi, E-mail: s.ohmura.m4@cc.it-hiroshima.ac.jp [Research Center for Condensed Matter Physics, Department of Civil Engineering and Urban Design, Hiroshima Institute of Technology, Hiroshima 731-5193 (Japan); Tsuruta, Kenji [Department of Electrical and Electronic Engineering, Okayama University, Okayama 700-8530 (Japan); Shimojo, Fuyuki [Department of Physics, Kumamoto University, Kumamoto 860-8555 Japan (Japan); Nakano, Aiichiro [Collaboratory for Advanced Computing and Simulations, Department of Computer Science, Department of Physics & Astronomy, Department of Chemical Engineering & Materials Science, Department of Biological Sciences, University of Southern California, CA90089-024 (United States)

    2016-01-15

    Using ab-initio theoretical methods, we demonstrate possible enhancement of photo-conversion efficiency of an organic solar cell via intentional doping in molecular graphene-fullerene heterojunction [the hexabenzocoronene (HBC)-triethylene glycol (TEG)–C{sub 60} molecule]. Photoabsorption analysis indicates oxygen substitution into HBC leads to an extension of the spectra up to an infrared regime. A quantum-mechanical molecular dynamics simulation incorporating nonadiabatic electronic transitions reveals that a dissociated charge state (D{sup +} and A{sup -}) in the O-doped system is more stable than the pristine case due to the presence of an effective barrier by the TEG HOMO/LUMO level. We also find that oxygen doping in HBC enhances the intermolecular carrier mobility after charge separation. On the other hand, the pristine molecule undergoes rapid recombination between donor and acceptor charges at the interface. These analyses suggest that the graphene oxidation opens a new window in the application of organic super-molecules to solar cells.

  6. Intramolecular charge separation in spirobifluorene-based donor–acceptor compounds adsorbed on Au and indium tin oxide electrodes

    International Nuclear Information System (INIS)

    Heredia, Daniel; Otero, Luis; Gervaldo, Miguel; Fungo, Fernando; Dittrich, Thomas; Lin, Chih-Yen; Chi, Liang-Chen; Fang, Fu-Chuan; Wong, Ken-Tsung

    2013-01-01

    Surface photovoltage (SPV) measurements were performed with a Kelvin-probe in spirobifluorene-based donor (diphenylamine)–acceptor (dicyano or cyanoacrylic acid moieties) compounds adsorbed from highly diluted solutions onto Au and indium tin oxide electrode surfaces. Strong intramolecular charge separation (negative SPV signals up to more than 0.1 V) due to directed molecule adsorption was observed only for spirobifluorene donor–acceptor compounds with carboxylic acid moiety. SPV signals and onset energies of electronic transitions depended on ambience conditions. - Highlights: ► Fluorene donor–acceptor derivatives were adsorbed at Au and indium tin oxide. ► Surface photovoltage measurements were performed with a Kelvin-probe. ► Strong intra-molecular charge separation was observed. ► SPV signals depended on ambience conditions

  7. Beam-energy dependence of charge separation along the magnetic field in Au+Au collisions at RHIC.

    Science.gov (United States)

    Adamczyk, L; Adkins, J K; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Alford, J; Anson, C D; Aparin, A; Arkhipkin, D; Aschenauer, E C; Averichev, G S; Banerjee, A; Beavis, D R; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bichsel, H; Bielcik, J; Bielcikova, J; Bland, L C; Bordyuzhin, I G; Borowski, W; Bouchet, J; Brandin, A V; Brovko, S G; Bültmann, S; Bunzarov, I; Burton, T P; Butterworth, J; Caines, H; Calderón de la Barca Sánchez, M; Cebra, D; Cendejas, R; Cervantes, M C; Chaloupka, P; Chang, Z; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, L; Cheng, J; Cherney, M; Chikanian, A; Christie, W; Chwastowski, J; Codrington, M J M; Contin, G; Cramer, J G; Crawford, H J; Cui, X; Das, S; Davila Leyva, A; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; Derradi de Souza, R; Dhamija, S; di Ruzza, B; Didenko, L; Dilks, C; Ding, F; Djawotho, P; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Engle, K S; Eppley, G; Eun, L; Evdokimov, O; Eyser, O; Fatemi, R; Fazio, S; Fedorisin, J; Filip, P; Finch, E; Fisyak, Y; Flores, C E; Gagliardi, C A; Gangadharan, D R; Garand, D; Geurts, F; Gibson, A; Girard, M; Gliske, S; Greiner, L; Grosnick, D; Gunarathne, D S; Guo, Y; Gupta, A; Gupta, S; Guryn, W; Haag, B; Hamed, A; Han, L-X; Haque, R; Harris, J W; Heppelmann, S; Hirsch, A; Hoffmann, G W; Hofman, D J; Horvat, S; Huang, B; Huang, H Z; Huang, X; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Kesich, A; Khan, Z H; Kikola, D P; Kisel, I; Kisiel, A; Koetke, D D; Kollegger, T; Konzer, J; Koralt, I; Kotchenda, L; Kraishan, A F; Kravtsov, P; Krueger, K; Kulakov, I; Kumar, L; Kycia, R A; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; LeVine, M J; Li, C; Li, W; Li, X; Li, X; Li, Y; Li, Z M; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Lomnitz, M; Longacre, R S; Luo, X; Ma, G L; Ma, Y G; Madagodagettige Don, D M M D; Mahapatra, D P; Majka, R; Margetis, S; Markert, C; Masui, H; Matis, H S; McDonald, D; McShane, T S; Minaev, N G; Mioduszewski, S; Mohanty, B; Mondal, M M; Morozov, D A; Mustafa, M K; Nandi, B K; Nasim, Md; Nayak, T K; Nelson, J M; Nigmatkulov, G; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Ohlson, A; Okorokov, V; Oldag, E W; Olvitt, D L; Pachr, M; Page, B S; Pal, S K; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlak, T; Pawlik, B; Pei, H; Perkins, C; Peryt, W; Pile, P; Planinic, M; Pluta, J; Poljak, N; Porter, J; Poskanzer, A M; Pruthi, N K; Przybycien, M; Pujahari, P R; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, R; Raniwala, S; Ray, R L; Riley, C K; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Ross, J F; Roy, A; Ruan, L; Rusnak, J; Rusnakova, O; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandweiss, J; Sangaline, E; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, B; Shen, W Q; Shi, S S; Shou, Q Y; Sichtermann, E P; Singaraju, R N; Skoby, M J; Smirnov, D; Smirnov, N; Solanki, D; Sorensen, P; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stevens, J R; Stock, R; Strikhanov, M; Stringfellow, B; Sumbera, M; Sun, X; Sun, X M; Sun, Y; Sun, Z; Surrow, B; Svirida, D N; Symons, T J M; Szelezniak, M A; Takahashi, J; Tang, A H; Tang, Z; Tarnowsky, T; Thomas, J H; Timmins, A R; Tlusty, D; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Trzeciak, B A; Tsai, O D; Turnau, J; Ullrich, T; Underwood, D G; Van Buren, G; van Nieuwenhuizen, G; Vandenbroucke, M; Vanfossen, J A; Varma, R; Vasconcelos, G M S; Vasiliev, A N; Vertesi, R; Videbæk, F; Viyogi, Y P; Vokal, S; Voloshin, S A; Vossen, A; Wada, M; Wang, F; Wang, G; Wang, H; Wang, J S; Wang, X L; Wang, Y; Wang, Y; Webb, G; Webb, J C; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y F; Xiao, Z; Xie, W; Xin, K; Xu, H; Xu, J; Xu, N; Xu, Q H; Xu, Y; Xu, Z; Yan, W; Yang, C; Yang, Y; Yang, Y; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I-K; Yu, N; Zawisza, Y; Zbroszczyk, H; Zha, W; Zhang, J B; Zhang, J L; Zhang, S; Zhang, X P; Zhang, Y; Zhang, Z P; Zhao, F; Zhao, J; Zhong, C; Zhu, X; Zhu, Y H; Zoulkarneeva, Y; Zyzak, M

    2014-08-01

    Local parity-odd domains are theorized to form inside a quark-gluon plasma which has been produced in high-energy heavy-ion collisions. The local parity-odd domains manifest themselves as charge separation along the magnetic field axis via the chiral magnetic effect. The experimental observation of charge separation has previously been reported for heavy-ion collisions at the top RHIC energies. In this Letter, we present the results of the beam-energy dependence of the charge correlations in Au+Au collisions at midrapidity for center-of-mass energies of 7.7, 11.5, 19.6, 27, 39, and 62.4 GeV from the STAR experiment. After background subtraction, the signal gradually reduces with decreased beam energy and tends to vanish by 7.7 GeV. This implies the dominance of hadronic interactions over partonic ones at lower collision energies.

  8. Beam-Energy Dependence of Charge Separation along the Magnetic Field in Au +Au Collisions at RHIC

    Science.gov (United States)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Beavis, D. R.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bültmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chwastowski, J.; Codrington, M. J. M.; Contin, G.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Das, S.; Davila Leyva, A.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Derradi de Souza, R.; Dhamija, S.; di Ruzza, B.; Didenko, L.; Dilks, C.; Ding, F.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Engle, K. S.; Eppley, G.; Eun, L.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Filip, P.; Finch, E.; Fisyak, Y.; Flores, C. E.; Gagliardi, C. A.; Gangadharan, D. R.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Gliske, S.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Haag, B.; Hamed, A.; Han, L.-X.; Haque, R.; Harris, J. W.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huang, X.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Kotchenda, L.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; LeVine, M. J.; Li, C.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, Y. G.; Madagodagettige Don, D. M. M. D.; Mahapatra, D. P.; Majka, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; McShane, T. S.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Olvitt, D. L.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Sun, X.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szelezniak, M. A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wada, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, X. L.; Wang, Y.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, J.; Xu, N.; Xu, Q. H.; Xu, Y.; Xu, Z.; Yan, W.; Yang, C.; Yang, Y.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zawisza, Y.; Zbroszczyk, H.; Zha, W.; Zhang, J. B.; Zhang, J. L.; Zhang, S.; Zhang, X. P.; Zhang, Y.; Zhang, Z. P.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, X.; Zhu, Y. H.; Zoulkarneeva, Y.; Zyzak, M.; STAR Collaboration

    2014-08-01

    Local parity-odd domains are theorized to form inside a quark-gluon plasma which has been produced in high-energy heavy-ion collisions. The local parity-odd domains manifest themselves as charge separation along the magnetic field axis via the chiral magnetic effect. The experimental observation of charge separation has previously been reported for heavy-ion collisions at the top RHIC energies. In this Letter, we present the results of the beam-energy dependence of the charge correlations in Au +Au collisions at midrapidity for center-of-mass energies of 7.7, 11.5, 19.6, 27, 39, and 62.4 GeV from the STAR experiment. After background subtraction, the signal gradually reduces with decreased beam energy and tends to vanish by 7.7 GeV. This implies the dominance of hadronic interactions over partonic ones at lower collision energies.

  9. Design and synthesis of bipyridine platinum(II) bisalkynyl fullerene donor-chromophore-acceptor triads with ultrafast charge separation.

    Science.gov (United States)

    Lee, Sai-Ho; Chan, Chris Tsz-Leung; Wong, Keith Man-Chung; Lam, Wai Han; Kwok, Wai-Ming; Yam, Vivian Wing-Wah

    2014-07-16

    Donor-chromophore-acceptor triads, (PTZ)2-Pt(bpy)-C60 and ((t)BuPTZ)2-Pt(bpy)-C60, along with their model compound, (Ph)2-Pt(bpy)-C60, have been synthesized and characterized; their photophysical and electrochemical properties have been studied, and the origin of the absorption and emission properties has been supported by computational studies. The photoinduced electron transfer reactions have been investigated using the femtosecond and nanosecond transient absorption spectroscopy. In dichloromethane, (Ph)2-Pt(bpy)-C60 shows ultrafast triplet-triplet energy transfer from the (3)MLCT/LLCT excited state within 4 ps to give the (3)C60* state, while in (PTZ)2-Pt(bpy)-C60 and ((t)BuPTZ)2-Pt(bpy)-C60, charge-separated state forms within 400 fs from the (3)MLCT/LLCT excited state with efficiency of over 0.90, and the total efficiency with the contribution of (3)C60* is estimated to be 0.99. Although the forward electron transfer reactions are very rapid, the charge-separated state recombines to the singlet ground state at a time of hundreds of nanoseconds because of the difference in spin multiplicity between the charge-separated state and the ground state.

  10. Global Warming Responses at the Primary Secondary Interface: 1. Students' Beliefs and Willingness to Act

    Science.gov (United States)

    Skamp, Keith; Boyes, Eddie; Stannistreet, Martin

    2009-01-01

    Using survey methodology, students' beliefs, and willingness to act, about 16 specific actions related to global warming are compared across the primary secondary interface. More primary students believed in the effectiveness of most actions to reduce global warming and were willing to take those actions. In general there was a disparity between…

  11. Accumulative charge separation for solar fuels production: coupling light-induced single electron transfer to multielectron catalysis.

    Science.gov (United States)

    Hammarström, Leif

    2015-03-17

    The conversion and storage of solar energy into a fuel holds promise to provide a significant part of the future renewable energy demand of our societies. Solar energy technologies today generate heat or electricity, while the large majority of our energy is used in the form of fuels. Direct conversion of solar energy to a fuel would satisfy our needs for storable energy on a large scale. Solar fuels can be generated by absorbing light and converting its energy to chemical energy by electron transfer leading to separation of electrons and holes. The electrons are used in the catalytic reduction of a cheap substrate with low energy content into a high-energy fuel. The holes are filled by oxidation of water, which is the only electron source available for large scale solar fuel production. Absorption of a single photon typically leads to separation of a single electron-hole pair. In contrast, fuel production and water oxidation are multielectron, multiproton reactions. Therefore, a system for direct solar fuel production must be able to accumulate the electrons and holes provided by the sequential absorption of several photons in order to complete the catalytic reactions. In this Account, the process is termed accumulative charge separation. This is considerably more complicated than charge separation on a single electron level and needs particular attention. Semiconductor materials and molecular dyes have for a long time been optimized for use in photovoltaic devices. Efforts are made to develop new systems for light harvesting and charge separation that are better optimized for solar fuel production than those used in the early devices presented so far. Significant progress has recently been made in the discovery and design of better homogeneous and heterogeneous catalysts for solar fuels and water oxidation. While the heterogeneous ones perform better today, molecular catalysts based on transition metal complexes offer much greater tunability of electronic and

  12. Ab initio modeling of primary processes in photosynthesis : protein induced activation of bacteriochlorophylls for efficient light harvesting and charge separation

    NARCIS (Netherlands)

    Wawrzyniak, Piotr K.

    2011-01-01

    Everything started in 1780 when Joseph Priestley, an English chemist, enclosed a mint plant and a burning candle in a glass jar. Surprisingly, the candle burned without interruption, even though in earlier experiments it was extinguished quickly when no plant was present in the jar. Now, 230 years

  13. How exciton-vibrational coherences control charge separation in the photosystem II reaction center

    NARCIS (Netherlands)

    Novoderezhkin, V.I.; Romero Mesa, E.; van Grondelle, R.

    2015-01-01

    In photosynthesis absorbed sun light produces collective excitations (excitons) that form a coherent superposition of electronic and vibrational states of the individual pigments. Two-dimensional (2D) electronic spectroscopy allows a visualization of how these coherences are involved in the primary

  14. Charge Separation in Intermixed Polymer:PC70BM Photovoltaic Blends: Correlating Structural and Photophysical Length Scales as a Function of Blend Composition

    KAUST Repository

    Utzat, Hendrik; Dimitrov, Stoichko D.; Wheeler, Scot; Collado-Fregoso, Elisa; Tuladhar, Pabitra Shakya; Schroeder, Bob C.; McCulloch, Iain; Durrant, James R.

    2017-01-01

    A key challenge in achieving control over photocurrent generation by bulk-heterojunction organic solar cells is understanding how the morphology of the active layer impacts charge separation and in particular the separation dynamics within

  15. The impact of long-range electron-hole interaction on the charge separation yield of molecular photocells

    Science.gov (United States)

    Nemati Aram, Tahereh; Ernzerhof, Matthias; Asgari, Asghar; Mayou, Didier

    2017-01-01

    We discuss the effects of charge carrier interaction and recombination on the operation of molecular photocells. Molecular photocells are devices where the energy conversion process takes place in a single molecular donor-acceptor complex attached to electrodes. Our investigation is based on the quantum scattering theory, in particular on the Lippmann-Schwinger equation; this minimizes the complexity of the problem while providing useful and non-trivial insight into the mechanism governing photocell operation. In this study, both exciton pair creation and dissociation are treated in the energy domain, and therefore there is access to detailed spectral information, which can be used as a framework to interpret the charge separation yield. We demonstrate that the charge carrier separation is a complex process that is affected by different parameters, such as the strength of the electron-hole interaction and the non-radiative recombination rate. Our analysis helps to optimize the charge separation process and the energy transfer in organic solar cells and in molecular photocells.

  16. The influence of microstructure on charge separation dynamics in organic bulk heterojunction materials for solar cell applications

    KAUST Repository

    Scarongella, Mariateresa; Paraecattil, Arun Aby; Buchaca-Domingo, Ester; Douglas, Jessica D.; Beaupré , Serge; McCarthy-Ward, Thomas; Heeney, Martin J.; Moser, Jacques Edouard; Leclerc, Mario; Frechet, Jean; Stingelin, Natalie; Banerji, Natalie

    2014-01-01

    Light-induced charge formation is essential for the generation of photocurrent in organic solar cells. In order to gain a better understanding of this complex process, we have investigated the femtosecond dynamics of charge separation upon selective excitation of either the fullerene or the polymer in different bulk heterojunction blends with well-characterized microstructure. Blends of the pBTTT and PBDTTPD polymers with PCBM gave us access to three different scenarios: either a single intermixed phase, an intermixed phase with additional pure PCBM clusters, or a three-phase microstructure of pure polymer aggregates, pure fullerene clusters and intermixed regions. We found that ultrafast charge separation (by electron or hole transfer) occurs predominantly in intermixed regions, while charges are generated more slowly from excitons in pure domains that require diffusion to a charge generation site. The pure domains are helpful to prevent geminate charge recombination, but they must be sufficiently small not to become exciton traps. By varying the polymer packing, backbone planarity and chain length, we have shown that exciton diffusion out of small polymer aggregates in the highly efficient PBDTTPD:PCBM blend occurs within the same chain and is helped by delocalization. This journal is © the Partner Organisations 2014.

  17. Charge separation in branched TiO_2 nanorod array homojunction aroused by quantum effect for enhanced photocatalytic decomposition of gaseous benzene

    International Nuclear Information System (INIS)

    Wang, Xiaoxia; Ni, Qian; Zeng, Dawen; Liao, Guanglan; Xie, Changsheng

    2016-01-01

    Highlights: • Charge separation in homojunction based on the broadened band gap by quantum effect. • Absolute charge separation by the passivation effect of TiO_2 nanorod. • Long-distance electron transfer behavior in photocatalysis. • Roughed surface for enhanced light harvesting by light trapping effect. - Abstract: As known, the electron transfer behavior in photocatalysis is short-distance transportation, which leads the photo-induced electrons and holes to be localized. The temporarily separated electrons and holes will recombine with each other in the localized region. In this paper, we successfully achieved electron transfer in a homojunction of branched rutile TiO_2 nanorod @nanoparticle core-shell architecture by quantum confinement effect aroused by the nanoparticle, which is proved by the blue-shifting in UV–vis absorption spectrum of the homojunction. Meanwhile, an absolute charge separation is also achieved by the long-distance electron transfer along the single-crystalline rutile TiO_2 nanorod as uninterrupted high-speed electron transfer channel to FTO substrates. Based on the effective charge separation, the photocatalytic decomposition of gaseous benzene by the homojunction is significantly enhanced, yielding 10 times CO_2 than that of the nanorod array. This homojunction interfacial charge separation, aroused by quantum effect, through long-distance transfer along the single-crystalline nanorod gives us inspiration to achieve efficient charge separation with defect-less interfaces, which might can be utilized for real-time environmental abatement and energy generation simultaneously.

  18. Charge separation in branched TiO{sub 2} nanorod array homojunction aroused by quantum effect for enhanced photocatalytic decomposition of gaseous benzene

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaoxia [State Key Laboratory of Materials and Processing Die & Mould Technology, Nanomaterials and Smart Sensors Research Laboratory, Department of Materials Science and Engineering, Huazhong University of Science and Technology, No. 1037, Luoyu Road, Wuhan 430074 (China); Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Wuhan 430062 (China); Ni, Qian [State Key Laboratory of Materials and Processing Die & Mould Technology, Nanomaterials and Smart Sensors Research Laboratory, Department of Materials Science and Engineering, Huazhong University of Science and Technology, No. 1037, Luoyu Road, Wuhan 430074 (China); Zeng, Dawen, E-mail: dwzeng@mail.hust.edu.cn [State Key Laboratory of Materials and Processing Die & Mould Technology, Nanomaterials and Smart Sensors Research Laboratory, Department of Materials Science and Engineering, Huazhong University of Science and Technology, No. 1037, Luoyu Road, Wuhan 430074 (China); Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Wuhan 430062 (China); Liao, Guanglan [State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, No. 1037, Luoyu Road, Wuhan 430074 (China); Xie, Changsheng [State Key Laboratory of Materials and Processing Die & Mould Technology, Nanomaterials and Smart Sensors Research Laboratory, Department of Materials Science and Engineering, Huazhong University of Science and Technology, No. 1037, Luoyu Road, Wuhan 430074 (China)

    2016-12-15

    Highlights: • Charge separation in homojunction based on the broadened band gap by quantum effect. • Absolute charge separation by the passivation effect of TiO{sub 2} nanorod. • Long-distance electron transfer behavior in photocatalysis. • Roughed surface for enhanced light harvesting by light trapping effect. - Abstract: As known, the electron transfer behavior in photocatalysis is short-distance transportation, which leads the photo-induced electrons and holes to be localized. The temporarily separated electrons and holes will recombine with each other in the localized region. In this paper, we successfully achieved electron transfer in a homojunction of branched rutile TiO{sub 2} nanorod @nanoparticle core-shell architecture by quantum confinement effect aroused by the nanoparticle, which is proved by the blue-shifting in UV–vis absorption spectrum of the homojunction. Meanwhile, an absolute charge separation is also achieved by the long-distance electron transfer along the single-crystalline rutile TiO{sub 2} nanorod as uninterrupted high-speed electron transfer channel to FTO substrates. Based on the effective charge separation, the photocatalytic decomposition of gaseous benzene by the homojunction is significantly enhanced, yielding 10 times CO{sub 2} than that of the nanorod array. This homojunction interfacial charge separation, aroused by quantum effect, through long-distance transfer along the single-crystalline nanorod gives us inspiration to achieve efficient charge separation with defect-less interfaces, which might can be utilized for real-time environmental abatement and energy generation simultaneously.

  19. Utilizing the dynamic stark shift as a probe for dielectric relaxation in photosynthetic reaction centers during charge separation.

    Science.gov (United States)

    Guo, Zhi; Lin, Su; Woodbury, Neal W

    2013-09-26

    In photosynthetic reaction centers, the electric field generated by light-induced charge separation produces electrochromic shifts in the transitions of reaction center pigments. The extent of this Stark shift indirectly reflects the effective field strength at a particular cofactor in the complex. The dynamics of the effective field strength near the two monomeric bacteriochlorophylls (BA and BB) in purple photosynthetic bacterial reaction centers has been explored near physiological temperature by monitoring the time-dependent Stark shift during charge separation (dynamic Stark shift). This dynamic Stark shift was determined through analysis of femtosecond time-resolved absorbance change spectra recorded in wild type reaction centers and in four mutants at position M210. In both wild type and the mutants, the kinetics of the dynamic Stark shift differ from those of electron transfer, though not in the same way. In wild type, the initial electron transfer and the increase in the effective field strength near the active-side monomer bacteriochlorophyll (BA) occur in synchrony, but the two signals diverge on the time scale of electron transfer to the quinone. In contrast, when tyrosine is replaced by aspartic acid at M210, the kinetics of the BA Stark shift and the initial electron transfer differ, but transfer to the quinone coincides with the decay of the Stark shift. This is interpreted in terms of differences in the dynamics of the local dielectric environment between the mutants and the wild type. In wild type, comparison of the Stark shifts associated with BA and BB on the two quasi-symmetric halves of the reaction center structure confirm that the effective dielectric constants near these cofactors are quite different when the reaction center is in the state P(+)QA(-), as previously determined by Steffen et al. at 1.5 K (Steffen, M. A.; et al. Science 1994, 264, 810-816). However, it is not possible to determine from static, low-temperature measurments if the

  20. The effect of solvent relaxation time constants on free energy gap law for ultrafast charge recombination following photoinduced charge separation.

    Science.gov (United States)

    Mikhailova, Valentina A; Malykhin, Roman E; Ivanov, Anatoly I

    2018-05-16

    To elucidate the regularities inherent in the kinetics of ultrafast charge recombination following photoinduced charge separation in donor-acceptor dyads in solutions, the simulations of the kinetics have been performed within the stochastic multichannel point-transition model. Increasing the solvent relaxation time scales has been shown to strongly vary the dependence of the charge recombination rate constant on the free energy gap. In slow relaxing solvents the non-equilibrium charge recombination occurring in parallel with solvent relaxation is very effective so that the charge recombination terminates at the non-equilibrium stage. This results in a crucial difference between the free energy gap laws for the ultrafast charge recombination and the thermal charge transfer. For the thermal reactions the well-known Marcus bell-shaped dependence of the rate constant on the free energy gap is realized while for the ultrafast charge recombination only a descending branch is predicted in the whole area of the free energy gap exceeding 0.2 eV. From the available experimental data on the population kinetics of the second and first excited states for a series of Zn-porphyrin-imide dyads in toluene and tetrahydrofuran solutions, an effective rate constant of the charge recombination into the first excited state has been calculated. The obtained rate constant being very high is nearly invariable in the area of the charge recombination free energy gap from 0.2 to 0.6 eV that supports the theoretical prediction.

  1. Molecular approaches to solar energy conversion: the energetic cost of charge separation from molecular-excited states.

    Science.gov (United States)

    Durrant, James R

    2013-08-13

    This review starts with a brief overview of the technological potential of molecular-based solar cell technologies. It then goes on to focus on the core scientific challenge associated with using molecular light-absorbing materials for solar energy conversion, namely the separation of short-lived, molecular-excited states into sufficiently long-lived, energetic, separated charges capable of generating an external photocurrent. Comparisons are made between different molecular-based solar cell technologies, with particular focus on the function of dye-sensitized photoelectrochemical solar cells as well as parallels with the function of photosynthetic reaction centres. The core theme of this review is that generating charge carriers with sufficient lifetime and a high quantum yield from molecular-excited states comes at a significant energetic cost-such that the energy stored in these charge-separated states is typically substantially less than the energy of the initially generated excited state. The role of this energetic loss in limiting the efficiency of solar energy conversion by such devices is emphasized, and strategies to minimize this energy loss are compared and contrasted.

  2. Cyanobacterial flv4-2 Operon-Encoded Proteins Optimize Light Harvesting and Charge Separation in Photosystem II.

    Science.gov (United States)

    Chukhutsina, Volha; Bersanini, Luca; Aro, Eva-Mari; van Amerongen, Herbert

    2015-05-01

    Photosystem II (PSII) complexes drive the water-splitting reaction necessary to transform sunlight into chemical energy. However, too much light can damage and disrupt PSII. In cyanobacteria, the flv4-2 operon encodes three proteins (Flv2, Flv4, and Sll0218), which safeguard PSII activity under air-level CO2 and in high light conditions. However, the exact mechanism of action of these proteins has not been clarified yet. We demonstrate that the PSII electron transfer properties are influenced by the flv4-2 operon-encoded proteins. Accelerated secondary charge separation kinetics was observed upon expression/overexpression of the flv4-2 operon. This is likely induced by docking of the Flv2/Flv4 heterodimer in the vicinity of the QB pocket of PSII, which, in turn, increases the QB redox potential and consequently stabilizes forward electron transfer. The alternative electron transfer route constituted by Flv2/Flv4 sequesters electrons from QB(-) guaranteeing the dissipation of excess excitation energy in PSII under stressful conditions. In addition, we demonstrate that in the absence of the flv4-2 operon-encoded proteins, about 20% of the phycobilisome antenna becomes detached from the reaction centers, thus decreasing light harvesting. Phycobilisome detachment is a consequence of a decreased relative content of PSII dimers, a feature observed in the absence of the Sll0218 protein. Copyright © 2015 The Author. Published by Elsevier Inc. All rights reserved.

  3. Exciplexes versus Loose Ion Pairs: How Does the Driving Force Impact the Initial Product Ratio of Photoinduced Charge Separation Reactions?

    Science.gov (United States)

    2014-01-01

    Many donor–acceptor systems can undergo a photoinduced charge separation reaction, yielding loose ion pairs (LIPs). LIPs can be formed either directly via (distant) electron transfer (ET) or indirectly via the dissociation of an initially formed exciplex or tight ion pair. Establishing the prevalence of one of the reaction pathways is challenging because differentiating initially formed exciplexes from LIPs is difficult due to similar spectroscopic footprints. Hence, no comprehensive reaction model has been established for moderately polar solvents. Here, we employ an approach based on the time-resolved magnetic field effect (MFE) of the delayed exciplex luminescence to distinguish the two reaction channels. We focus on the effects of the driving force of ET and the solvent permittivity. We show that, surprisingly, the exciplex channel is significant even for an exergonic ET system with a free energy of ET of −0.58 eV and for the most polar solutions studied (butyronitrile). Our findings demonstrate that exciplexes play a crucial role even in polar solvents and at moderate driving forces, contrary to what is usually assumed. PMID:25243054

  4. Enhancement of plasmon-induced charge separation efficiency by coupling silver nanocubes with a thin gold film

    Science.gov (United States)

    Akiyoshi, Kazutaka; Saito, Koichiro; Tatsuma, Tetsu

    2016-10-01

    Plasmon-induced charge separation (PICS), in which an energetic electron is injected from a plasmonic nanoparticle (NP) to a semiconductor on contact, is often inhibited by a protecting agent adsorbed on the NP. We addressed this issue for an Ag nanocube-TiO2 system by coating it with a thin Au layer or by inserting the Au layer between the nanocubes (NCs) and TiO2. Both of the electrodes exhibit much higher photocurrents due to PICS than the electrodes without the Au film or the Ag NCs. These photocurrent enhancements can be explained in terms of PICS with accelerated electron transfer, in which electron injection from the Ag NCs or Ag@Au core-shell NCs to TiO2 is promoted by the Au film, or PICS enhanced by a nanoantenna effect, in which the electron injection from the Au film to TiO2 is enhanced by optical near field generated by the Ag NC.

  5. Photosynthesis: The Path of Carbon in Photosynthesis and the Primary Quantum Conversion Act of Photosynthesis

    Science.gov (United States)

    Calvin, Melvin

    1952-11-22

    This constitutes a review of the path of carbon in photosynthesis as it has been elaborated through the summer of 1952, with particular attention focused on those aspects of carbon metabolism and its variation which have led to some direct information regarding the primary quantum conversion act. An introduction to the arguments which have been adduced in support of the idea that chlorophyll is a physical sensitizer handing its excitation on to thioctic acid, a compound containing a strained 1, 2 -dithiolcyclopentane ring, is given.

  6. Primary photosynthetic processes: from supercomplex to leaf

    NARCIS (Netherlands)

    Broess, K.

    2009-01-01

    This thesis describes fluorescence spectroscopy experiments on photosynthetic complexes that cover the primary photosynthetic processes, from the absorption of light by photosynthetic pigments to a charge separation (CS) in the reaction center (RC). Fluorescence spectroscopy is a useful tool in

  7. Polarization Energies at Organic–Organic Interfaces: Impact on the Charge Separation Barrier at Donor–Acceptor Interfaces in Organic Solar Cells

    KAUST Repository

    Ryno, Sean

    2016-05-31

    We probe the energetic landscape at a model pentacene/fullerene-C60 interface to investigate the interactions between positive and negative charges, which are critical to the processes of charge separation and recombination in organic solar cells. Using a polarizable force field, we find that polarization energy, i.e. the stabilization a charge feels due to its environment, is larger at the interface than in the bulk for both a positive and a negative charge. The combination of the charge being more stabilized at the interface and the Coulomb attraction between the charges, results in a barrier to charge separation at the pentacene-C60 interface that can be in excess of 0.7 eV for static configurations of the donor and acceptor locations. However, the impact of molecular motions, i.e., the dynamics, at the interface at room temperature results in a distribution of polarization energies and in charge separation barriers that can be significantly reduced. The dynamic nature of the interface is thus critical, with the polarization energy distributions indicating that sites along the interface shift in time between favorable and unfavorable configurations for charge separation.

  8. Extension of the charge separated-state lifetime by supramolecular association of a tetrathiafulvalene electron donor to a zinc/gold bisporphyrin.

    Science.gov (United States)

    Boixel, Julien; Fortage, Jérôme; Blart, Errol; Pellegrin, Yann; Hammarström, Leif; Becker, Hans-Christian; Odobel, Fabrice

    2010-02-14

    Supramolecular triads were prepared by self-assembly of 4'-pyridyl-2-tetrathiafulvalene axially bound on ZnP-spacer-AuP(+) dyads; the lifetime of the charge separated state ((+)TTF-ZnP-Spacer-AuP ) formed upon light excitation of the triad is greatly increased with respect to that found in the parent dyad.

  9. Polarization Energies at Organic–Organic Interfaces: Impact on the Charge Separation Barrier at Donor–Acceptor Interfaces in Organic Solar Cells

    KAUST Repository

    Ryno, Sean; Fu, Yao-Tsung; Risko, Chad; Bredas, Jean-Luc

    2016-01-01

    more stabilized at the interface and the Coulomb attraction between the charges, results in a barrier to charge separation at the pentacene-C60 interface that can be in excess of 0.7 eV for static configurations of the donor and acceptor locations

  10. Improving the Photo-Oxidative Performance of Bi2MoO6 by Harnessing the Synergy between Spatial Charge Separation and Rational Co-Catalyst Deposition.

    Science.gov (United States)

    Wu, Xuelian; Hart, Judy N; Wen, Xiaoming; Wang, Liang; Du, Yi; Dou, Shi Xue; Ng, Yun Hau; Amal, Rose; Scott, Jason

    2018-03-21

    It has been reported that photogenerated electrons and holes can be directed toward specific crystal facets of a semiconductor particle, which is believed to arise from the differences in their surface electronic structures, suggesting that different facets can act as either photoreduction or photo-oxidation sites. This study examines the propensity for this effect to occur in faceted, plate-like bismuth molybdate (Bi 2 MoO 6 ), which is a useful photocatalyst for water oxidation. Photoexcited electrons and holes are shown to be spatially separated toward the {100} and {001}/{010} facets of Bi 2 MoO 6 , respectively, by facet-dependent photodeposition of noble metals (Pt, Au, and Ag) and metal oxides (PbO 2 , MnO x , and CoO x ). Theoretical calculations revealed that differences in energy levels between the conduction bands and valence bands of the {100} and {001}/{010} facets can contribute to electrons and holes being drawn to different surfaces of the plate-like Bi 2 MoO 6 . Utilizing this knowledge, the photo-oxidative capability of Bi 2 MoO 6 was improved by adding an efficient water oxidation co-catalyst, CoO x , to the system, whereby the extent of enhancement was shown to be governed by the co-catalyst location. A greater oxygen evolution occurred when CoO x was selectively deposited on the hole-rich {001}/{010} facets of Bi 2 MoO 6 compared to when CoO x was randomly located across all of the facets. The elevated performance exhibited for the selectively loaded CoO x /Bi 2 MoO 6 was ascribed to the greater opportunity for hole trapping by the co-catalyst being accentuated over other potentially detrimental effects, such as the co-catalyst acting as a recombination medium and/or covering reactive sites. The results indicate that harnessing the synergy between the spatial charge separation and the co-catalyst location on the appropriate facets of plate-like Bi 2 MoO 6 can promote its photocatalytic activity.

  11. Optogenetic analysis of a nociceptor neuron and network reveals ion channels acting downstream of primary sensors

    Science.gov (United States)

    Husson, Steven J.; Costa, Wagner Steuer; Wabnig, Sebastian; Stirman, Jeffrey N.; Watson, Joseph D.; Spencer, W. Clay; Akerboom, Jasper; Looger, Loren L.; Treinin, Millet; Miller, David M.; Lu, Hang; Gottschalk, Alexander

    2012-01-01

    Summary Background Nociception generally evokes rapid withdrawal behavior in order to protect the tissue from harmful insults. Most nociceptive neurons responding to mechanical insults display highly branched dendrites, an anatomy shared by Caenorhabditis elegans FLP and PVD neurons, which mediate harsh touch responses. Although several primary molecular nociceptive sensors have been characterized, less is known about modulation and amplification of noxious signals within nociceptor neurons. First, we analyzed the FLP/PVD network by optogenetics and studied integration of signals from these cells in downstream interneurons. Second, we investigated which genes modulate PVD function, based on prior single neuron mRNA profiling of PVD. Results Selectively photoactivating PVD, FLP and downstream interneurons using Channelrhodopsin-2 (ChR2) enabled functionally dissecting this nociceptive network, without interfering signals by other mechanoreceptors. Forward or reverse escape behaviors were determined by PVD and FLP, via integration by command interneurons. To identify mediators of PVD function, acting downstream of primary nocisensor molecules, we knocked down PVD-specific transcripts by RNAi and quantified light-evoked PVD-dependent behavior. Cell-specific disruption of synaptobrevin or voltage-gated Ca2+-channels (VGCCs) showed that PVD signals chemically to command interneurons. Knocking down the DEG/ENaC channel ASIC-1 and the TRPM channel GTL-1 indicated that ASIC-1 may extend PVD’s dynamic range and that GTL-1 may amplify its signals. These channels act cell-autonomously in PVD, downstream of primary mechanosensory molecules. Conclusions Our work implicates TRPM channels in modifying excitability of, and DEG/ENaCs in potentiating signal output from a mechano-nociceptor neuron. ASIC-1 and GTL-1 homologues, if functionally conserved, may denote valid targets for novel analgesics. PMID:22483941

  12. A more than six orders of magnitude UV-responsive organic field-effect transistor utilizing a benzothiophene semiconductor and Disperse Red 1 for enhanced charge separation.

    Science.gov (United States)

    Smithson, Chad S; Wu, Yiliang; Wigglesworth, Tony; Zhu, Shiping

    2015-01-14

    A more than six orders of magnitude UV-responsive organic field-effect transistor is developed using a benzothiophene (BTBT) semiconductor and strong donor-acceptor Disperse Red 1 as the traps to enhance charge separation. The device can be returned to its low drain current state by applying a short gate bias, and is completely reversible with excellent stability under ambient conditions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Transient and modulated charge separation at CuInSe{sub 2}/C{sub 60} and CuInSe{sub 2}/ZnPc hybrid interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Morzé, Natascha von, E-mail: natascha.von_morze@helmholtz-berlin.de; Dittrich, Thomas, E-mail: dittrich@helmholtz-berlin.de; Calvet, Wolfram, E-mail: wolfram.calvet@helmholtz-berlin.de; Lauermann, Iver, E-mail: iver.lauermann@helmholtz-berlin.de; Rusu, Marin, E-mail: rusu@helmholtz-berlin.de

    2017-02-28

    Highlights: • Surface physical properties of non- and Na-treated CuInSe{sub 2} layers studied. • Evidence of exciton dissociation and charge separation at CuInSe{sub 2}/ZnPc interface. • Strong band bending at the CuInSe{sub 2} surface in contact with C{sub 60} observed. • No evidence for exciton dissociation at the CuInSe{sub 2}/C{sub 60} interface found. • Cu-poor phase at CuInSe{sub 2}/organic interface crucial for charge separation. - Abstract: Spectral dependent charge transfer and exciton dissociation have been investigated at hybrid interfaces between inorganic polycrystalline CuInSe{sub 2} (untreated and Na-conditioned) thin films and organic C{sub 60} as well as zinc phthalocyanine (ZnPc) layers by transient and modulated surface photovoltage measurements. The stoichiometry and electronic properties of the bare CuInSe{sub 2} surface were characterized by photoelectron spectroscopy which revealed a Cu-poor phase with n-type features. After the deposition of the C{sub 60} layer, a strong band bending at the CuInSe{sub 2} surface was observed. Evidence for dissociation of excitons followed by charge separation was found at the CuInSe{sub 2}/ZnPc interface. The Cu-poor layer at the CuInSe{sub 2} surface was found to be crucial for transient and modulated charge separation at CuInSe{sub 2}/organic hybrid interfaces.

  14. Long-Lived Photoinduced Charge Separation in a Trinuclear Iron-μ 3 -oxo-based Metal–Organic Framework

    Energy Technology Data Exchange (ETDEWEB)

    Hanna, Lauren [Department; Kucheryavy, Pavel [Department; Liu, Cunming [X-ray; Zhang, Xiaoyi [X-ray; Lockard, Jenny V. [Department

    2017-06-14

    The presence of long-lived charge-separated excited states in metal-organic frameworks (MOFs) can enhance their photocatalytic activity by decreasing the probability that photogenerated electrons and holes recombine before accessing adsorbed reactants. Detecting these charge separated states via optical transient absorption, however, can be challenging when they lack definitive optical signatures. Here, we investigate the long-lived excited state of a MOF with such vague optical properties, MIL-100(Fe), comprised of Fe3-μ3-oxo clusters and trimesic acid linkers using Fe K-edge X-ray transient absorption (XTA) spectroscopy, to unambiguously determine its ligand-to-metal charge transfer character. Spectra measured at time delays up to 3.6 μs confirm the long lived nature of the charge separated excited state. Several trinuclear iron μ3- oxo carboxylate complexes, which model the trinuclear cores of the MOF structure, are measured for comparison using both steady state XAS and XTA to further support this assignment and corresponding decay time. The MOF is prepared as a colloidal nanoparticle suspension for these measurements so both its fabrication and particle size analysis are presented, as well.

  15. Dynamical mechanism of charge separation by photoexcited generation of proton–electron pairs in organic molecular systems. A nonadiabatic electron wavepacket dynamics study

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Kentaro, E-mail: kyamamoto@fukui.kyoto-u.ac.jp; Takatsuka, Kazuo, E-mail: kaztak@fukui.kyoto-u.ac.jp

    2016-08-22

    Graphical abstract: Asymptotic biradical state produced by the excited-state coupled proton–electron transfer (CPET), resulting in charge separation (proton–electron pair creation) on a proton–electron acceptor A, in a series of photochemical systems generally denoted as X–Mn–OH{sub 2}⋯A, where X = (OH, Ca(OH){sub 3}) and A = (N-methylformamidine, guanidine, imidazole, or ammonia clusters). - Abstract: In this perspective article, we review, along with presenting new results, a series of our theoretical analyses on the excited-state mechanism of charge separation (proton–electron pair creation) relevant to the photoinduced water-splitting reaction (2H{sub 2}O → 4H{sup +} + 4e{sup −} + O{sub 2}) in organic and biological systems, which quite often includes Mn clusters in various molecular configurations. The present mechanism is conceived to be universal in the triggering process of the photoexcited water splitting dynamics. In other words, any Mn-based catalytic charge separation is quite likely to be initiated according to this mechanism. As computationally tractable yet realistic models, we examine a series of systems generally expressed as X–Mn–OH{sub 2}⋯A, where X = (OH, Ca(OH){sub 3}) and A = (N-methylformamidine, guanidine, imidazole or ammonia cluster) in terms of the theory of nonadiabatic electron wavepacket dynamics. We first find both an electron and a proton are simultaneously transferred to the acceptors through conical intersections upon photoexcitation. In this mechanism, the electron takes different pathways from that of the proton and reaches the densely lying Rydberg-like states of the acceptors in the end, thereby inducing charge separation. Therefore the presence of the Rydberg-like diffused unoccupied states as an electron acceptor is critical for this reaction to proceed. We also have found another crucial nonadiabatic process that deteriorates the efficiency of charge separation by rendering the created pair of proton

  16. Final Technical Report for the Energy Frontier Research Center Understanding Charge Separation and Transfer at Interfaces in Energy Materials (EFRC:CST)

    Energy Technology Data Exchange (ETDEWEB)

    Vanden Bout, David A. [Univ. of Texas, Austin, TX (United States)

    2015-09-14

    Our EFRC was founded with the vision of creating a broadly collaborative and synergistic program that would lead to major breakthroughs in the molecular-level understanding of the critical interfacial charge separation and charge transfer (CST) processes that underpin the function of candidate materials for organic photovoltaic (OPV) and electrical-energy-storage (EES) applications. Research in these energy contexts shares an imposing challenge: How can we understand charge separation and transfer mechanisms in the presence of immense materials complexity that spans multiple length scales? To address this challenge, our 50-member Center undertook a total of 28 coordinated research projects aimed at unraveling the CST mechanisms that occur at interfaces in these nanostructured materials. This rigorous multi-year study of CST interfaces has greatly illuminated our understanding of early-timescale processes (e.g., exciton generation and dissociation dynamics at OPV heterojunctions; control of Li+-ion charging kinetics by surface chemistry) occurring in the immediate vicinity of interfaces. Program outcomes included: training of 72 graduate student and postdoctoral energy researchers at 5 institutions and spanning 7 academic disciplines in science and engineering; publication of 94 peer-reviewed journal articles; and dissemination of research outcomes via 340 conference, poster and other presentations. Major scientific outcomes included: implementation of a hierarchical strategy for understanding the electronic communication mechanisms and ultimate fate of charge carriers in bulk heterojunction OPV materials; systematic investigation of ion-coupled electron transfer processes in model Li-ion battery electrode/electrolyte systems; and the development and implementation of 14 unique technologies and instrumentation capabilities to aid in probing sub-ensemble charge separation and transfer mechanisms.

  17. Effect of different photoanode nanostructures on the initial charge separation and electron injection process in dye sensitized solar cells: A photophysical study with indoline dyes

    Energy Technology Data Exchange (ETDEWEB)

    Idígoras, Jesús [Nanostructured Solar Cells Group, Department of Physical, Chemical and Natural Systems, Universidad Pablo de Olavide, Ctra. Utrera, km 1, ES-41013 Seville (Spain); Sobuś, Jan [NanoBioMedical Centre, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań (Poland); Quantum Electronics Laboratory, Faculty of Physics, Adam Mickiewicz University in Poznań, Umultowska 85, 61-614 Poznań (Poland); Jancelewicz, Mariusz [NanoBioMedical Centre, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań (Poland); Azaceta, Eneko; Tena-Zaera, Ramon [Materials Division, IK4-CIDETEC, Parque Tecnológico de San Sebastián, Paseo Miramón 196, Donostia-San Sebastián, 20009 (Spain); Anta, Juan A. [Nanostructured Solar Cells Group, Department of Physical, Chemical and Natural Systems, Universidad Pablo de Olavide, Ctra. Utrera, km 1, ES-41013 Seville (Spain); Ziółek, Marcin, E-mail: marziol@amu.edu.pl [Quantum Electronics Laboratory, Faculty of Physics, Adam Mickiewicz University in Poznań, Umultowska 85, 61-614 Poznań (Poland)

    2016-02-15

    Ultrafast and fast charge separation processes were investigated for complete cells based on several ZnO-based photoanode nanostructures and standard TiO{sub 2} nanoparticle layers sensitized with the indoline dye coded D358. Different ZnO morphologies (nanoparticles, nanowires, mesoporous), synthesis methods (hydrothermal, gas-phase, electrodeposition in aqueous media and ionic liquid media) and coatings (ZnO–ZnO core–shell, ZnO–TiO{sub 2} core–shell) were measured by transient absorption techniques in the time scale from 100 fs to 100 μs and in the visible and near-infrared spectral range. All of ZnO cells show worse electron injection yields with respect to those with standard TiO{sub 2} material. Lower refractive index of ZnO than that of TiO{sub 2} is suggested to be an additional factor, not considered so far, that can decrease the performance of ZnO-based solar cells. Evidence of the participation of the excited charge transfer state of the dye in the charge separation process is provided here. The lifetime of this state in fully working devices extends from several ps to several tens of ps, which is much longer than the typically postulated electron injection times in all-organic dye-sensitized solar cells. The results here provided, comprising a wide variety of morphologies and preparation methods, point to the universality of the poor performance of ZnO as photoanode material with respect to standard TiO{sub 2}. - Highlights: • Wide variety of morphologies and preparation methods has been checked for ZnO cells. • All ZnO cells work worse than TiO{sub 2} ones. • Effective refractive index might be an additional factor in solar cell performance. • Excited charge transfer state of indoline dyes participates in the charge separation.

  18. Visible-light-driven TiO2/Ag3PO4/GO heterostructure photocatalyst with dual-channel for photo-generated charges separation

    International Nuclear Information System (INIS)

    Lu, Bingqing; Ma, Ni; Wang, Yaping; Qiu, Yiwei; Hu, Haihua; Zhao, Jiahuan; Liang, Dayu; Xu, Sheng; Li, Xiaoyun; Zhu, Zhiyan; Cui, Can

    2015-01-01

    Highlights: • TiO 2 /Ag 3 PO 4 /GO was synthesized with a facile two-step method. • TiO 2 /Ag 3 PO 4 /GO exhibit superior photocatalytic activity and stability. • TiO 2 /Ag 3 PO 4 /GO has dual-channel for photo-generated charges separation. • TiO 2 /Ag 3 PO 4 /GO composite reduces the consumption of Ag. - Abstract: A novel triple-component TiO 2 /Ag 3 PO 4 /graphene oxide (TiO 2 /Ag 3 PO 4 /GO) photocatalyst with dual channels for photo-generated charges separation has been synthesized to improve the photocatalytic activity and stability of Ag 3 PO 4 under visible light. The synthesis involved in-situ growth of Ag 3 PO 4 nanoparticles on GO sheets to form Ag 3 PO 4 /GO, and then deposited TiO 2 nanocrystals on the surface of Ag 3 PO 4 by hydrolysis of Ti(SO 4 ) 2 at low-temperature hydrothermal condition. The TiO 2 /Ag 3 PO 4 /GO exhibited superior photocatalytic activity and stability to bare Ag 3 PO 4 , TiO 2 /Ag 3 PO 4 and Ag 3 PO 4 /GO in degradation of Rhodamine B and phenol solutions under visible light. It is suggested that the photo-generated electrons in the conduction band of Ag 3 PO 4 can be quickly transferred to GO, while the holes in the valence band of Ag 3 PO 4 can be transferred to the valence band of TiO 2 . The dual transfer channels at the interfaces of TiO 2 /Ag 3 PO 4 /GO result in effective charges separation, leading to enhanced photocatalytic activity and stability. Furthermore, the content of noble metal Ag significantly reduces from 77 wt% in bare Ag 3 PO 4 to 55 wt% in the nanocomposite. The concept of establishing dual channels for charges separation in a triple-component heterostructure provides a promising way to develop photocatalysts with high efficiency

  19. Trapping Dynamics in Photosystem I-Light Harvesting Complex I of Higher Plants Is Governed by the Competition Between Excited State Diffusion from Low Energy States and Photochemical Charge Separation.

    Science.gov (United States)

    Molotokaite, Egle; Remelli, William; Casazza, Anna Paola; Zucchelli, Giuseppe; Polli, Dario; Cerullo, Giulio; Santabarbara, Stefano

    2017-10-26

    The dynamics of excited state equilibration and primary photochemical trapping have been investigated in the photosystem I-light harvesting complex I isolated from spinach, by the complementary time-resolved fluorescence and transient absorption approaches. The combined analysis of the experimental data indicates that the excited state decay is described by lifetimes in the ranges of 12-16 ps, 32-36 ps, and 64-77 ps, for both detection methods, whereas faster components, having lifetimes of 550-780 fs and 4.2-5.2 ps, are resolved only by transient absorption. A unified model capable of describing both the fluorescence and the absorption dynamics has been developed. From this model it appears that the majority of excited state equilibration between the bulk of the antenna pigments and the reaction center occurs in less than 2 ps, that the primary charge separated state is populated in ∼4 ps, and that the charge stabilization by electron transfer is completed in ∼70 ps. Energy equilibration dynamics associated with the long wavelength absorbing/emitting forms harbored by the PSI external antenna are also characterized by a time mean lifetime of ∼75 ps, thus overlapping with radical pair charge stabilization reactions. Even in the presence of a kinetic bottleneck for energy equilibration, the excited state dynamics are shown to be principally trap-limited. However, direct excitation of the low energy chlorophyll forms is predicted to lengthen significantly (∼2-folds) the average trapping time.

  20. Charge Separation in Intermixed Polymer:PC70BM Photovoltaic Blends: Correlating Structural and Photophysical Length Scales as a Function of Blend Composition

    KAUST Repository

    Utzat, Hendrik

    2017-04-24

    A key challenge in achieving control over photocurrent generation by bulk-heterojunction organic solar cells is understanding how the morphology of the active layer impacts charge separation and in particular the separation dynamics within molecularly intermixed donor-acceptor domains versus the dynamics between phase-segregated domains. This paper addresses this issue by studying blends and devices of the amorphous silicon-indacenodithiophene polymer SiIDT-DTBT and the acceptor PCBM. By changing the blend composition, we modulate the size and density of the pure and intermixed domains on the nanometer length scale. Laser spectroscopic studies show that these changes in morphology correlate quantitatively with the changes in charge separation dynamics on the nanosecond time scale and with device photocurrent densities. At low fullerene compositions, where only a single, molecularly intermixed polymer-fullerene phase is observed, photoexcitation results in a ∼ 30% charge loss from geminate polaron pair recombination, which is further studied via light intensity experiments showing that the radius of the polaron pairs in the intermixed phase is 3-5 nm. At high fullerene compositions (≥67%), where the intermixed domains are 1-3 nm and the pure fullerene phases reach ∼4 nm, the geminate recombination is suppressed by the reduction of the intermixed phase, making the fullerene domains accessible for electron escape.

  1. The rates of charge separation and energy destructive charge recombination processes within an organic dyad in presence of metal-semiconductor core shell nanocomposites.

    Science.gov (United States)

    Mandal, Gopa; Bhattacharya, Sudeshna; Das, Subrata; Ganguly, Tapan

    2012-01-01

    Steady state and time resolved spectroscopic measurements were made at the ambient temperature on an organic dyad, 1-(4-Chloro-phenyl)-3-(4-methoxy-naphthalen-1-yl)-propenone (MNCA), where the donor 1-methoxynaphthalene (1 MNT) is connected with the acceptor p-chloroacetophenone (PCA) by an unsaturated olefinic bond, in presence of Ag@TiO2 nanoparticles. Time resolved fluorescence and absorption measurements reveal that the rate parameters associated with charge separation, k(CS), within the dyad increases whereas charge recombination rate k(CR) reduces significantly when the surrounding medium is changed from only chloroform to mixture of chloroform and Ag@TiO2 (noble metal-semiconductor) nanocomposites. The observed results indicate that the dyad being combined with core-shell nanocomposites may form organic-inorganic nanocomposite system useful for developing light energy conversion devices. Use of metal-semiconductor nanoparticles may provide thus new ways to modulate charge recombination processes in light energy conversion devices. From comparison with the results obtained in our earlier investigations with only TiO2 nanoparticles, it is inferred that much improved version of light energy conversion device, where charge-separated species could be protected for longer period of time of the order of millisecond, could be designed by using metal-semiconductor core-shell nanocomposites rather than semiconductor nanoparticles only.

  2. Ultrafast Exciton Dissociation and Long-Lived Charge Separation in a Photovoltaic Pentacene-MoS2 van der Waals Heterojunction.

    Science.gov (United States)

    Bettis Homan, Stephanie; Sangwan, Vinod K; Balla, Itamar; Bergeron, Hadallia; Weiss, Emily A; Hersam, Mark C

    2017-01-11

    van der Waals heterojunctions between two-dimensional (2D) layered materials and nanomaterials of different dimensions present unique opportunities for gate-tunable optoelectronic devices. Mixed-dimensional p-n heterojunction diodes, such as p-type pentacene (0D) and n-type monolayer MoS 2 (2D), are especially interesting for photovoltaic applications where the absorption cross-section and charge transfer processes can be tailored by rational selection from the vast library of organic molecules and 2D materials. Here, we study the kinetics of excited carriers in pentacene-MoS 2 p-n type-II heterojunctions by transient absorption spectroscopy. These measurements show that the dissociation of MoS 2 excitons occurs by hole transfer to pentacene on the time scale of 6.7 ps. In addition, the charge-separated state lives for 5.1 ns, up to an order of magnitude longer than the recombination lifetimes from previously reported 2D material heterojunctions. By studying the fractional amplitudes of the MoS 2 decay processes, the hole transfer yield from MoS 2 to pentacene is found to be ∼50%, with the remaining holes undergoing trapping due to surface defects. Overall, the ultrafast charge transfer and long-lived charge-separated state in pentacene-MoS 2 p-n heterojunctions suggest significant promise for mixed-dimensional van der Waals heterostructures in photovoltaics, photodetectors, and related optoelectronic technologies.

  3. Spin dynamics of light-induced charge separation in composites of semiconducting polymers and PC60BM revealed using Q-band pulse EPR.

    Science.gov (United States)

    Lukina, E A; Suturina, E; Reijerse, E; Lubitz, W; Kulik, L V

    2017-08-23

    Light-induced processes in composites of semiconducting polymers and fullerene derivatives have been widely studied due to their usage as active layers of organic solar cells. However the process of charge separation under light illumination - the key process of an organic solar cell is not well understood yet. Here we report a Q-band pulse electron paramagnetic resonance study of composites of the fullerene derivative PC 60 BM ([6,6]-phenyl-C 61 -butyric acid methyl ester) with different p-type semiconducting polymers regioregular and regiorandom P3HT (poly(3-hexylthiophene-2,5-diyl), MEH-PPV (poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene]), PCDTBT (poly[N-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)]), PTB7 (poly({4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl}))), resulting in a detailed description of the in-phase laser flash-induced electron spin echo (ESE) signal. We found that in organic donor-acceptor composites the laser flash simultaneously induces species of two types: a polymer˙ + /fullerene˙ - spin-correlated polaron pair (SCPP) with an initial singlet spin state and (nearly) free polymer˙ + and fullerene˙ - species with non-equilibrium spin polarization. Species of the first type (SCPP) are well-known for polymer/fullerene blends and are usually associated with a charge-separated state. Also, spin polarization of long-living free species (polarons in deep traps) is affected by the laser flash, which is the third contribution to the flash-induced ESE signal. A protocol for extracting the in-phase ESE signal of the SCPP based on the dependence of the microwave nutation frequency on the strength of the spin coupling within the polaron pair was developed. Nutation experiments revealed an unusual pattern of the SCPP in RR-P3HT/PC 60 BM composites, from which the strength of the exchange interaction between the polymer

  4. Stability and charge separation of different CH3NH3SnI3/TiO2 interface: A first-principles study

    Science.gov (United States)

    Yang, Zhenzhen; Wang, Yuanxu; Liu, Yunyan

    2018-05-01

    Interface has an important effect on charge separation of perovskite solar cells. Using first-principles calculations, we studied several different interfaces between CH3NH3SnI3 and TiO2. The interfacial structure and electronic structure of these interfaces are thoroughly explored. We found that the SnI2/anatase (SnI2/A) system is more stable than the other three systems, because an anatase surface can make Snsbnd I bond faster restore to the pristine value than a rutile surface, and SnI2/A system has a smaller standard deviation. The calculated plane-averaged electrostatic potential and the density of states suggest that SnI2/anatase interface has a better separation of photo-generated electron-hole pairs.

  5. Direct evidence of charge separation in a metal-organic framework: efficient and selective photocatalytic oxidative coupling of amines via charge and energy transfer.

    Science.gov (United States)

    Xu, Caiyun; Liu, Hang; Li, Dandan; Su, Ji-Hu; Jiang, Hai-Long

    2018-03-28

    The selective aerobic oxidative coupling of amines under mild conditions is an important laboratory and commercial procedure yet a great challenge. In this work, a porphyrinic metal-organic framework, PCN-222, was employed to catalyze the reaction. Upon visible light irradiation, the semiconductor-like behavior of PCN-222 initiates charge separation, evidently generating oxygen-centered active sites in Zr-oxo clusters indicated by enhanced porphyrin π-cation radical signals. The photogenerated electrons and holes further activate oxygen and amines, respectively, to give the corresponding redox products, both of which have been detected for the first time. The porphyrin motifs generate singlet oxygen based on energy transfer to further promote the reaction. As a result, PCN-222 exhibits excellent photocatalytic activity, selectivity and recyclability, far superior to its organic counterpart, for the reaction under ambient conditions via combined energy and charge transfer.

  6. B-side charge separation in bacterial photosynthetic reaction centers: nanosecond time scale electron transfer from HB- to QB.

    Science.gov (United States)

    Kirmaier, Christine; Laible, Philip D; Hanson, Deborah K; Holten, Dewey

    2003-02-25

    We report time-resolved optical measurements of the primary electron transfer reactions in Rhodobacter capsulatus reaction centers (RCs) having four mutations: Phe(L181) --> Tyr, Tyr(M208) --> Phe, Leu(M212) --> His, and Trp(M250) --> Val (denoted YFHV). Following direct excitation of the bacteriochlorophyll dimer (P) to its lowest excited singlet state P, electron transfer to the B-side bacteriopheophytin (H(B)) gives P(+)H(B)(-) in approximately 30% yield. When the secondary quinone (Q(B)) site is fully occupied, P(+)H(B)(-) decays with a time constant estimated to be in the range of 1.5-3 ns. In the presence of excess terbutryn, a competitive inhibitor of Q(B) binding, the observed lifetime of P(+)H(B)(-) is noticeably longer and is estimated to be in the range of 4-8 ns. On the basis of these values, the rate constant for P(+)H(B)(-) --> P(+)Q(B)(-) electron transfer is calculated to be between approximately (2 ns)(-)(1) and approximately (12 ns)(-)(1), making it at least an order of magnitude smaller than the rate constant of approximately (200 ps)(-)(1) for electron transfer between the corresponding A-side cofactors (P(+)H(A)(-) --> P(+)Q(A)(-)). Structural and energetic factors associated with electron transfer to Q(B) compared to Q(A) are discussed. Comparison of the P(+)H(B)(-) lifetimes in the presence and absence of terbutryn indicates that the ultimate (i.e., quantum) yield of P(+)Q(B)(-) formation relative to P is 10-25% in the YFHV RC.

  7. Interfacial charge separation and recombination in InP and quasi-type II InP/CdS core/shell quantum dot-molecular acceptor complexes.

    Science.gov (United States)

    Wu, Kaifeng; Song, Nianhui; Liu, Zheng; Zhu, Haiming; Rodríguez-Córdoba, William; Lian, Tianquan

    2013-08-15

    Recent studies of group II-VI colloidal semiconductor heterostuctures, such as CdSe/CdS core/shell quantum dots (QDs) or dot-in-rod nanorods, show that type II and quasi-type II band alignment can facilitate electron transfer and slow down charge recombination in QD-molecular electron acceptor complexes. To explore the general applicability of this wave function engineering approach for controlling charge transfer properties, we investigate exciton relaxation and dissociation dynamics in InP (a group III-V semiconductor) and InP/CdS core/shell (a heterostructure beween group III-V and II-VI semiconductors) QDs by transient absorption spectroscopy. We show that InP/CdS QDs exhibit a quasi-type II band alignment with the 1S electron delocalized throughout the core and shell and the 1S hole confined in the InP core. In InP-methylviologen (MV(2+)) complexes, excitons in the QD can be dissociated by ultrafast electron transfer to MV(2+) from the 1S electron level (with an average time constant of 11.4 ps) as well as 1P and higher electron levels (with a time constant of 0.39 ps), which is followed by charge recombination to regenerate the complex in its ground state (with an average time constant of 47.1 ns). In comparison, InP/CdS-MV(2+) complexes show similar ultrafast charge separation and 5-fold slower charge recombination rates, consistent with the quasi-type II band alignment in these heterostructures. This result demonstrates that wave function engineering in nanoheterostructures of group III-V and II-VI semiconductors provides a promising approach for optimizing their light harvesting and charge separation for solar energy conversion applications.

  8. The place of central-acting drugs in the algorithms of treatment of primary obesity

    Directory of Open Access Journals (Sweden)

    Oksana V. Logvinova

    2017-09-01

    Full Text Available Pharmacotherapy is an essential component of obesity treatment, as well as efforts focused on changing the lifestyle, correcting the food consumption and increasing the physical activity. The administration of central-acting drugs as pharmacotherapy of obesity is pathogenetically justified and allows improving the effectiveness of treatment. In this article, the use of sibutramine, a serotonin and norepinephrine reuptake inhibitor, is considered in various aspects of endocrinologist’s practice. In addition to aforesaid there is an application of a specific clinical observation.

  9. A self-consistent two-dimensional resistive fluid theory of field-aligned potential structures including charge separation and magnetic and velocity shear

    International Nuclear Information System (INIS)

    Hesse, M.; Birn, J.; Schindler, K.

    1990-01-01

    A self-consistent two-fluid theory that includes the magnetic field and shear patterns therein is developed to model stationary electrostatic structures with field-aligned potential drops. Shear flow is also included in the theory since this seems to be a prominent feature of the structures of interest. In addition, Ohmic dissipation, a Hall term and pressure gradients in a generalized Ohm's law, modified for cases without quasi-neutrality are included. In the analytic theory, the electrostatic force is balanced by field-aligned pressure gradients, i.e., thermal effects in the direction of the magnetic field, and by pressure gradients and magnetic stresses in the perpendicular direction. Within this theory simple examples of applications are presented to demonstrate the kind of solutions resulting from the model. The results show how the effects of charge separation and shear in the magnetic field and the velocity can be combined to form self-consistent structures such as are found to exist above the aurora, suggested also in association with solar flares

  10. Antiferroelectric Nature of CH3NH3PbI3-xClx Perovskite and Its Implication for Charge Separation in Perovskite Solar Cells

    Science.gov (United States)

    Sewvandi, Galhenage A.; Kodera, Kei; Ma, Hao; Nakanishi, Shunsuke; Feng, Qi

    2016-07-01

    Perovskite solar cells (PSCs) have been attracted scientific interest due to high performance. Some researchers have suggested anomalous behavior of PSCs to the polarizations due to the ion migration or ferroelectric behavior. Experimental results and theoretical calculations have suggested the possibility of ferroelectricity in organic-inorganic perovskite. However, still no studies have been concretely discarded the ferroelectric nature of perovskite absorbers in PSCs. Hysteresis of P-E (polarization-electric field) loops is an important evidence to confirm the ferroelectricity. In this study, P-E loop measurements, in-depth structural study, analyses of dielectric behavior and the phase transitions of CH3NH3PbI3-xClx perovskite were carried out and investigated. The results suggest that CH3NH3PbI3-xClx perovskite is in an antiferroelectric phase at room temperature. The antiferroelectric phase can be switched to ferroelectric phase by the poling treatment and exhibits ferroelectric-like hysteresis P-E loops and dielectric behavior around room temperature; namely, the perovskite can generate a ferroelectric polarization under PSCs operating conditions. Furthermore, we also discuss the implications of ferroelectric polarization on PSCs charge separation.

  11. [Spinal muscular atrophy and respiratory failure. How do primary care pediatricians act in a simulated scenario?].

    Science.gov (United States)

    Agra Tuñas, M C; Sánchez Santos, L; Busto Cuiñas, M; Rodríguez Núñez, A

    2015-11-01

    Spinal muscular atrophy type 1 (SMA-1) tends to be fatal in the first year of life if there is no ventilatory support. The decision whether to start such support is an ethical conflict for healthcare professionals. A scenario of acute respiratory failure in an infant with SMA-1 has been included in a training program using advanced simulation for Primary Care pediatricians (PCP). The performances of 34 groups of 4 pediatricians, who participated in 17 courses, were systematically analyzed. Clinical, ethical and communication aspects with parents were evaluated. The initial technical assistance (Administration of oxygen and immediate ventilatory support) was correctly performed by 94% of the teams. However, the PCP had problems in dealing with the ethical aspects of the case. Of the 85% of the teams that raised the ethical conflict with parents, 29% did so on their own initiative, 23% actively excluded them, and only 6% involved them and took their opinion into account in making decisions. Only 11.7% asked about the quality of life of children and 12% for their knowledge of the prognosis of the disease. None explained treatment alternatives, nor tried to contact the pediatrician responsible for the child. When faced with a simulated SMA-1 infant with respiratory failure, PCP have difficulties in interacting with the family, and to involve it in the decision making process. Practical training of all pediatricians should include case scenarios with an ethical clinical problem. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

  12. Activating children's thinking skills (ACTS): the effects of an infusion approach to teaching thinking in primary schools.

    Science.gov (United States)

    Dewey, Jessica; Bento, Janet

    2009-06-01

    Recent interest in the teaching of thinking skills within education has led to an increase in thinking skills packages available to schools. However many of these are not based on scientific evaluation (DfEE, 1999). This paper endeavours to examine the effectiveness of one approach, that of infusion, to teaching thinking. To investigate the impact of an infusion methodology, activating children's thinking skills (ACTS), on the cognitive, social, and emotional development of children in Year 4-6 in primary schools. This is a sister project to research being conducted in Northern Ireland (McGuinness, 2006). The study involved 404 children from 8 primary schools in one local authority. These were divided into 160 in the experimental group and 244 in the waiting list control group. A quasi-experimental design was used with pre-, post-, and delayed post-tests to ascertain changes in children's cognitive abilities, self-perceptions, and social/behavioural skills using quantitative measures. In addition qualitative techniques were used with pupils and teachers to evaluate effectiveness. The experimental group made significantly greater gains in cognitive ability skills over a 2 year period compared to the waiting list control. Qualitative data demonstrated a positive impact on children's social and emotional development. In addition teacher professional development was reported to be enhanced. This research indicated that children's cognitive abilities can be developed following a 2 year period of the ACTS infusion intervention. While some positive effects were evidenced on the social and emotional development of children, further study will be necessary to examine these in more detail.

  13. Development of whole core thermal-hydraulic analysis program ACT. 3. Coupling core module with primary heat transport system module

    International Nuclear Information System (INIS)

    Ohtaka, Masahiko; Ohshima, Hiroyuki

    1998-10-01

    A whole core thermal-hydraulic analysis program ACT is being developed for the purpose of evaluating detailed in-core thermal hydraulic phenomena of fast reactors including inter-wrapper flow under various reactor operation conditions. In this work, the core module as a main part of the ACT developed last year, which simulates thermal-hydraulics in the subassemblies and the inter-subassembly gaps, was coupled with an one dimensional plant system thermal-hydraulic analysis code LEDHER to simulate transients in the primary heat transport system and to give appropriate boundary conditions to the core model. The effective algorithm to couple these two calculation modules was developed, which required minimum modification of them. In order to couple these two calculation modules on the computing system, parallel computing technique using PVM (Parallel Virtual Machine) programming environment was applied. The code system was applied to analyze an out-of-pile sodium experiment simulating core with 7 subassemblies under transient condition for code verification. It was confirmed that the analytical results show a similar tendency of experimental results. (author)

  14. Reduced graphene oxide wrapped Bi{sub 2}WO{sub 6} hybrid with ultrafast charge separation and improved photoelectrocatalytic performance

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Huan [School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, PR China (China); Liang, Yinghua, E-mail: liangyh@ncst.edu.cn [School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, PR China (China); College of Chemical Engineering, North China University of Science and Technology, Tangshan 063009, PR China (China); Liu, Li; Hu, Jinshan [College of Chemical Engineering, North China University of Science and Technology, Tangshan 063009, PR China (China); Cui, Wenquan, E-mail: wkcui@163.com [College of Chemical Engineering, North China University of Science and Technology, Tangshan 063009, PR China (China)

    2017-01-15

    Highlights: • The rGO wrapped Bi{sub 2}WO{sub 6} photoelectrode was successfully synthesized. • The Bi{sub 2}WO{sub 6}@rGOhighlyincreasedthechargeseparationefficiency. • The photoelectrode exhibited enhanced photoelectrocatalytic degradation for RhB. - Abstract: A reduced graphene oxide (rGO) wrapped Bi{sub 2}WO{sub 6} (Bi{sub 2}WO{sub 6}@rGO) hybrid as photoelectrode for enhanced photoelectrocatalytic (PEC) degradation of organic pollutants is reported, which exhibited excellent charge separation and photoconversion efficiency. The core@shell structured Bi{sub 2}WO{sub 6}@rGO photoelectrode yielded a pronounced 1.56-fold and 23.8-fold photocurrent density at 1.0 V vs. saturated calomel electrode (SCE), than that of loading structured Bi{sub 2}WO{sub 6}-rGO and pure Bi{sub 2}WO{sub 6}. The Bi{sub 2}WO{sub 6}@rGO hybrid exhibited enhanced photoelectrocatalytic efficiency for degradation of Rhodamine B (RhB), which was 43.0% and 65.6% higher than that of photocatalytic (PC) and electrocatalytic (EC) processes, respectively. The enhancement in PEC degradation of RhB benefited from: (1) a strong interaction and a wide range of conjugation were formed in the core@shell system; (2) a 0.26 V of flat band potential was negatively shifted in case of Bi{sub 2}WO{sub 6}@rGO composite; (3) the photogenerated electrons and holes could be spatially separated by external electric potentials.

  15. From Recombination Dynamics to Device Performance: Quantifying the Efficiency of Exciton Dissociation, Charge Separation, and Extraction in Bulk Heterojunction Solar Cells with Fluorine-Substituted Polymer Donors

    KAUST Repository

    Gorenflot, Julien

    2017-09-28

    An original set of experimental and modeling tools is used to quantify the yield of each of the physical processes leading to photocurrent generation in organic bulk heterojunction solar cells, enabling evaluation of materials and processing condition beyond the trivial comparison of device performances. Transient absorption spectroscopy, “the” technique to monitor all intermediate states over the entire relevant timescale, is combined with time-delayed collection field experiments, transfer matrix simulations, spectral deconvolution, and parametrization of the charge carrier recombination by a two-pool model, allowing quantification of densities of excitons and charges and extrapolation of their kinetics to device-relevant conditions. Photon absorption, charge transfer, charge separation, and charge extraction are all quantified for two recently developed wide-bandgap donor polymers: poly(4,8-bis((2-ethylhexyl)oxy)benzo[1,2-b:4,5-b′]dithiophene-3,4-difluorothiophene) (PBDT[2F]T) and its nonfluorinated counterpart poly(4,8-bis((2-ethylhexyl)oxy)benzo[1,2-b:4,5-b′]dithiophene-3,4-thiophene) (PBDT[2H]T) combined with PC71BM in bulk heterojunctions. The product of these yields is shown to agree well with the devices\\' external quantum efficiency. This methodology elucidates in the specific case studied here the origin of improved photocurrents obtained when using PBDT[2F]T instead of PBDT[2H]T as well as upon using solvent additives. Furthermore, a higher charge transfer (CT)-state energy is shown to lead to significantly lower energy losses (resulting in higher VOC) during charge generation compared to P3HT:PCBM.

  16. Adverse Effects of Excess Residual PbI2 on Photovoltaic Performance, Charge Separation, and Trap-State Properties in Mesoporous Structured Perovskite Solar Cells.

    Science.gov (United States)

    Wang, Hao-Yi; Hao, Ming-Yang; Han, Jun; Yu, Man; Qin, Yujun; Zhang, Pu; Guo, Zhi-Xin; Ai, Xi-Cheng; Zhang, Jian-Ping

    2017-03-17

    Organic-inorganic halide perovskite solar cells have rapidly come to prominence in the photovoltaic field. In this context, CH 3 NH 3 PbI 3 , as the most widely adopted active layer, has been attracting great attention. Generally, in a CH 3 NH 3 PbI 3 layer, unreacted PbI 2 inevitably coexists with the perovskite crystals, especially following a two-step fabrication process. There appears to be a consensus that an appropriate amount of unreacted PbI 2 is beneficial to the overall photovoltaic performance of a device, the only disadvantageous aspect of excess residual PbI 2 being viewed as its insulating nature. However, the further development of such perovskite-based devices requires a deeper understanding of the role of residual PbI 2 . In this work, PbI 2 -enriched and PbI 2 -controlled perovskite films, as two extreme cases, have been prepared by modulating the crystallinity of a pre-deposited PbI 2 film. The effects of excess residual PbI 2 have been elucidated on the basis of spectroscopic and optoelectronic studies. The initial charge separation, the trap-state density, and the trap-state distribution have all been found to be adversely affected in PbI 2 -enriched devices, to the detriment of photovoltaic performance. This leads to a biphasic recombination process and accelerates the charge carrier recombination dynamics. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. From Recombination Dynamics to Device Performance: Quantifying the Efficiency of Exciton Dissociation, Charge Separation, and Extraction in Bulk Heterojunction Solar Cells with Fluorine-Substituted Polymer Donors

    KAUST Repository

    Gorenflot, Julien; Paulke, Andreas; Piersimoni, Fortunato; Wolf, Jannic Sebastian; Kan, Zhipeng; Cruciani, Federico; El Labban, Abdulrahman; Neher, Dieter; Beaujuge, Pierre; Laquai, Fré dé ric

    2017-01-01

    An original set of experimental and modeling tools is used to quantify the yield of each of the physical processes leading to photocurrent generation in organic bulk heterojunction solar cells, enabling evaluation of materials and processing condition beyond the trivial comparison of device performances. Transient absorption spectroscopy, “the” technique to monitor all intermediate states over the entire relevant timescale, is combined with time-delayed collection field experiments, transfer matrix simulations, spectral deconvolution, and parametrization of the charge carrier recombination by a two-pool model, allowing quantification of densities of excitons and charges and extrapolation of their kinetics to device-relevant conditions. Photon absorption, charge transfer, charge separation, and charge extraction are all quantified for two recently developed wide-bandgap donor polymers: poly(4,8-bis((2-ethylhexyl)oxy)benzo[1,2-b:4,5-b′]dithiophene-3,4-difluorothiophene) (PBDT[2F]T) and its nonfluorinated counterpart poly(4,8-bis((2-ethylhexyl)oxy)benzo[1,2-b:4,5-b′]dithiophene-3,4-thiophene) (PBDT[2H]T) combined with PC71BM in bulk heterojunctions. The product of these yields is shown to agree well with the devices' external quantum efficiency. This methodology elucidates in the specific case studied here the origin of improved photocurrents obtained when using PBDT[2F]T instead of PBDT[2H]T as well as upon using solvent additives. Furthermore, a higher charge transfer (CT)-state energy is shown to lead to significantly lower energy losses (resulting in higher VOC) during charge generation compared to P3HT:PCBM.

  18. Knowledge and Acceptability of Long-Acting Reversible Contraception Among Adolescent Women Receiving School-Based Primary Care Services.

    Science.gov (United States)

    Hoopes, Andrea J; Ahrens, Kym R; Gilmore, Kelly; Cady, Janet; Haaland, Wren L; Amies Oelschlager, Anne-Marie; Prager, Sarah

    2016-07-01

    A key strategy to reduce unintended adolescent pregnancies is to expand access to long-acting reversible contraceptive (LARC) methods, including intrauterine devices and subdermal contraceptive implants. LARC services can be provided to adolescents in school-based health and other primary care settings, yet limited knowledge and negative attitudes about LARC methods may influence adolescents' utilization of these methods. This study aimed to evaluate correlates of knowledge and acceptability of LARC methods among adolescent women at a school-based health center (SBHC). In this cross-sectional study, female patients receiving care at 2 SBHCs in Seattle, Washington completed an electronic survey about sexual and reproductive health. Primary outcomes were (1) LARC knowledge as measured by percentage correct of 10 true-false questions and (2) LARC acceptability as measured by participants reporting either liking the idea of having an intrauterine device (IUD)/subdermal implant or currently using one. A total of 102 students diverse in race/ethnicity and socioeconomic backgrounds completed the survey (mean age 16.2 years, range 14.4-19.1 years). Approximately half reported a lifetime history of vaginal sex. Greater LARC knowledge was associated with white race (regression coefficient [coef] = 26.8; 95% CI 13.3-40.4; P use (coef = 22.8; 95% CI 6.5-40.0; P = .007). Older age was associated with lower IUD acceptability (odds ratio = 0.53, 95% CI 0.30-0.94; P = .029) while history of intercourse was associated with greater implant acceptability (odds ratio 5.66, 95% CI 1.46-22.0; P = .012). Adolescent women in this SBHC setting had variable knowledge and acceptability of LARC. A history of vaginal intercourse was the strongest predictor of LARC acceptability. Our findings suggest a need for LARC counseling and education strategies, particularly for young women from diverse cultural backgrounds and those with less sexual experience. © The Author(s) 2016.

  19. ACTS 2014

    DEFF Research Database (Denmark)

    Co-curator of ACTS 2014 together with Rasmus Holmboe, Judith Schwarzbart and Sanne Kofoed. ACTS is the Museum of Contemporary Art’s international bi-annual festival. ACTS was established in 2011 and, while the primary focus is on sound and performance art, it also looks toward socially oriented art....... For the 2014 festival, the museum has entered into a collaboration with the Department for Performance Design at Roskilde University – with continued focus on sound and performance art, and social art in public spaces. With ACTS, art moves out of its usual exhibition space and instead utilizes the city, its...... various possibilities and public spaces as a stage. ACTS takes place in and around the museum and diverse locations in Roskilde city. ACTS is partly curated by the museum staff and partly by guest curators. ACTS 2014 is supported by Nordea-fonden and is a part of the project The Museum goes downtown....

  20. A strong steric hindrance effect on ground state, excited state, and charge separated state properties of a CuI-diimine complex captured by X-ray transient absorption spectroscopy

    DEFF Research Database (Denmark)

    Huang, J.; Mara, M.W.; Stickrath, A.B.

    2014-01-01

    of phenanthroline. The structural dynamics of the photoinduced charge transfer process in the [CuI(dppS)2]+/TiO2 hybrid is also investigated, which suggests a more restricted environment for the complex upon binding to TiO2 NPs. Moreover, the Cu-N bond length of the oxidized state of [CuI(dppS)2]+ after electron...... dynamics and structures as well as those of the charge separated state resulting from the interfacial electron injection from the MLCT state to TiO2 nanoparticles (NPs). The OTA results show the absence of the sub-picosecond component previously assigned as the time constant for flattening, while the two...... injection to TiO2 NPs shortens by 0.05 Å compared to that in the ground state. The interpretation of these observed structural changes associated with excited and charge separated states will be discussed. These results not only set an example for applying XTA in capturing the intermediate structure...

  1. Challenges and opportunities in building a sustainable rural primary care workforce in alignment with the Affordable Care Act: the WWAMI program as a case study.

    Science.gov (United States)

    Allen, Suzanne M; Ballweg, Ruth A; Cosgrove, Ellen M; Engle, Kellie A; Robinson, Lawrence R; Rosenblatt, Roger A; Skillman, Susan M; Wenrich, Marjorie D

    2013-12-01

    The authors examine the potential impact of the Patient Protection and Affordable Care Act (ACA) on a large medical education program in the Northwest United States that builds the primary care workforce for its largely rural region. The 42-year-old Washington, Wyoming, Alaska, Montana, and Idaho (WWAMI) program, hosted by the University of Washington School of Medicine, is one of the nation's most successful models for rural health training. The program has expanded training and retention of primary care health professionals for the region through medical school education, graduate medical education, a physician assistant training program, and support for practicing health professionals.The ACA and resulting accountable care organizations (ACOs) present potential challenges for rural settings and health training programs like WWAMI that focus on building the health workforce for rural and underserved populations. As more Americans acquire health coverage, more health professionals will be needed, especially in primary care. Rural locations may face increased competition for these professionals. Medical schools are expanding their positions to meet the need, but limits on graduate medical education expansion may result in a bottleneck, with insufficient residency positions for graduating students. The development of ACOs may further challenge building a rural workforce by limiting training opportunities for health professionals because of competing demands and concerns about cost, efficiency, and safety associated with training. Medical education programs like WWAMI will need to increase efforts to train primary care physicians and increase their advocacy for student programs and additional graduate medical education for rural constituents.

  2. Kinetics of photocurrent generation and an efficient charge separation of a dye-sensitized n-Cu2O/p-CuSCN junction photoelectrode in a solid-state photovoltaic cell

    International Nuclear Information System (INIS)

    Fernando, C A N; Kumara, N T R N; Gamage, T N

    2010-01-01

    A Cu/n-Cu 2 O/dye/p-CuSCN junction photoelectrode is fabricated to produce a solid-state dye-sensitized photovoltaic cell. Samples are characterized by XRD, SEM and surface resistivity measurements. Photocurrent generation is found due to light absorption of n-Cu 2 O thin film and dye sensitization between p-CuSCN and the dye. Kinetics of the photocurrent generation of the dye sensitization is studied solving the rate equations by the iteration method obtaining a relationship for the photocurrent quantum efficiency (Φ) depending on the surface concentration (D o ) of the dye and the rate constants of the reactions with connection to the dye sensitization process. The solution obtained in the steady state by iteration is found to be of the form Φ = AD o −BD o 2 (A and B are constants related to the reaction rates of the photocurrent generation process and the concentration of the n-Cu 2 O film). The variation of the n-Cu 2 O concentration with photocurrent is presented. A photocurrent enhancement is observed for the Cu/n-Cu 2 O/dye/p-CuSCN photovoltaic cell compared to that of Cu/n-Cu 2 O, Cu/p-CuSCN/dye and Cu/n-Cu 2 O/p-CuSCN photovoltaic cells. Good rectification characteristics are observed for the Cu/n-Cu 2 O/p-CuSCN photoelectrode compared to that of Cu/n-Cu 2 O and Cu/p-CuSCN photoelectrodes. Photocurrent enhancement is found due to the efficient charge separation process at the n–p junction. Energy band structures of the n–p junction are proposed according to the onset potentials which are used to discuss the mechanism of the efficient charge separation suppressing the recombination process

  3. Spin-charge separation in quantum wires

    International Nuclear Information System (INIS)

    Yacoby, A.

    2004-01-01

    Full Text:Using momentum resolved tunneling between two clean parallel quantum wires in a AlGaAs/GaAs heterostructure we directly measure the dispersion of the quantum many-body modes in ballistic wires and follow their dependence on Coulomb interactions by varying the electron density. We find clear signatures of three excitation modes in the data: The anti-symmetric charge mode of the coupled wire system and two spin modes. The density dependence of the anti-symmetric charge mode agrees well with Luttinger-liquid theory. As the density of electrons is lowered, the Coulomb interaction is seen to become increasingly dominant leading to excitation velocities that are up to 2.5 times faster than the bare Fermi velocity, determined experimentally from the carrier density. The symmetric charge excitation, also expected from theory, is, however, not visible in the data. The observed spin velocities are found to be 25% slower than the bare Fermi velocities and depend linearly on carrier density. The dispersions are mapped down to a critical density at which spontaneous localization is observed. Some of the experimental findings concerning this phase will be discussed

  4. Reversible exciplex formation followed charge separation.

    Science.gov (United States)

    Petrova, M V; Burshtein, A I

    2008-12-25

    The reversible exciplex formation followed by its decomposition into an ion pair is considered, taking into account the subsequent geminate and bulk ion recombination to the triplet and singlet products (in excited and ground states). The integral kinetic equations are derived for all state populations, assuming that the spin conversion is performed by the simplest incoherent (rate) mechanism. When the forward and backward electron transfer is in contact as well as all dissociation/association reactions of heavy particles, the kernels of integral equations are specified and expressed through numerous reaction constants and characteristics of encounter diffusion. The solutions of these equations are used to specify the quantum yields of the excited state and exciplex fluorescence induced by pulse or stationary pumping. In the former case, the yields of the free ions and triplet products are also found, while in the latter case their stationary concentrations are obtained.

  5. 75 FR 63703 - Privacy Act of 1974; Privacy Act Regulation

    Science.gov (United States)

    2010-10-18

    ... FEDERAL RESERVE SYSTEM 12 CFR Part 261a [Docket No. R-1313] Privacy Act of 1974; Privacy Act... implementing the Privacy Act of 1974 (Privacy Act). The primary changes concern the waiver of copying fees... records under the Privacy Act; the amendment of special procedures for the release of medical records to...

  6. Williamson Act - The California Land Conservation Act of 1965

    Data.gov (United States)

    California Natural Resource Agency — The California Land Conservation Act of 1965 - commonly referred to as the Williamson Act - is the State's primary program for the conservation of private land in...

  7. Privacy Act

    Science.gov (United States)

    Learn about the Privacy Act of 1974, the Electronic Government Act of 2002, the Federal Information Security Management Act, and other information about the Environmental Protection Agency maintains its records.

  8. Primary structure and promoter analysis of leghemoglobin genes of the stem-nodulated tropical legume Sesbania rostrata: conserved coding sequences, cis-elements and trans-acting factors

    DEFF Research Database (Denmark)

    Metz, B A; Welters, P; Hoffmann, H J

    1988-01-01

    The primary structure of a leghemoglobin (lb) gene from the stem-nodulated, tropical legume Sesbania rostrata and two lb gene promoter regions was analysed. The S. rostrata lb gene structure and Lb amino acid composition were found to be highly conserved with previously described lb genes and Lb ...

  9. Promoting Reflexive Thinking and Adaptive Expertise through Video Capturing to Challenge Postgraduate Primary Student Teachers to Think, Know, Feel, and Act Like a Teacher

    Science.gov (United States)

    Sexton, Steven S.; Williamson-Leadley, Sandra

    2017-01-01

    This article reports on a study of how a 1-year, course-taught, master's level initial teacher education (ITE) program challenged primary student teachers (n = 4) in developing their sense of self-as-teacher. This study examined how the program's incorporation of video capturing technology impacted on these student teachers' development of…

  10. Indolo[3,2-b]carbazole inhibits gap junctional intercellular communication in rat primary hepatocytes and acts as a potential tumor promoter

    DEFF Research Database (Denmark)

    Herrmann, Susan; Seidelin, Michel; Bisgaard, Hanne Cathrine

    2002-01-01

    Indole-3-carbinol (I3C) is a naturally occurring substance that shows anti-carcinogenic properties in animal models. Besides its clear anti-carcinogenic effects, some studies indicate that I3C may sometimes act as a tumor promoter. Indolo[3,2-b]carbazole (ICZ), which is formed in the acidic...... environment of the stomach after intake of I3C, has a similar structure to, and shares biological effects with, the well-known tumor promoter 2,3,7,8-tetrachlorodibenzo-pdioxin (TCDD). Therefore, we hypothesized that ICZ could be responsible for the potential tumor-promoting activity of I3C. The aim...

  11. The use of electronic alerts in primary care computer systems to identify the excessive prescription of short-acting beta2-agonists for people with asthma: a systematic review.

    Science.gov (United States)

    McKibben, Shauna; De Simoni, Anna; Bush, Andy; Thomas, Mike; Griffiths, Chris

    2018-04-16

    Computers are increasingly used to improve prescribing decisions in the management of long-term conditions however the effects on asthma prescribing remain unclear. We aimed to synthesise the evidence for the use of computerised alerts that identify excessive prescribing of short-acting beta 2 -agonists (SABAs) to improve asthma management for people with asthma. MEDLINE, CINAHL, Embase, Cochrane and Scopus databases (1990-2016) were searched for randomised controlled trials using electronic alerts to identify excessive prescribing of SABAs for people with asthma in primary care. Inclusion eligibility, quality appraisal (Cochrane risk of bias tool) and data extraction were performed by two independent reviewers. Findings were synthesised narratively. A total of 2035 articles were screened and four trials were eligible. Three studies had low risk of bias: one reported a positive effect on our primary outcome of interest, excessive SABA prescribing; another reported positive effects on the ratio of inhaled corticosteroid (ICS)-SABA prescribing, and asthma control; a third reported no effect on outcomes of interest. One study at high risk of bias reported a reduction in exacerbations and primary care consultations. There is some evidence that electronic alerts reduce excessive prescribing of SABAs, when delivered as part of a multicomponent intervention in an integrated health care system. However due to the variation in health care systems, intervention design and outcomes measured, further research is required to establish optimal design of alerting and intervening systems.

  12. A CLAS act? Community-based organizations, health service decentralization and primary care development in Peru. Local Committees for Health Administration.

    Science.gov (United States)

    Iwami, Michiyo; Petchey, Roland

    2002-12-01

    In 1994 Peru embarked on a programme of health service reform, which combined primary care development and community participation through Local Committees for Health Administration (CLAS). They are responsible for carrying out local health needs assessments and identifying unmet health needs through regular household surveys. These enable them to determine local health provision and tailor services to local requirements. CLAS build on grassroots self-help circles that developed during the economic and political crises of the 1980s, and in which women have been prominent. However, they function under a 3 year contract with the Ministry of Health and within a framework of centrally determined guidelines and regulations. These reforms were implemented in the context of neo-liberal economic policies, which stressed financial deregulation and fiscal and monetary restraint, and were aimed at reducing foreign indebtedness and inflation. We evaluate the achievements of the CLAS and analyse the relationship between health and economic policy in Peru, with the aid of two contrasting models of the role of the state - 'agency' and 'stewardship'. We argue that Peru's experience holds valuable lessons for other countries seeking to foster community involvement. These include the need for community capacity building and partnership between community organizations and state (and other civil) agencies.

  13. Curatorial Acts

    NARCIS (Netherlands)

    Bal, M.

    2012-01-01

    In a self-critical inquiry into my own recent work of co-curating and the experience of seeing my video work being curated by others, this article examines acts of framing as performative acts that seek to transform visitors' preconceptions. This affective effect is pursued by means of immersion,

  14. ACT Test

    Science.gov (United States)

    ... to clot, the higher the degree of clotting inhibition. During surgery, the ACT is kept above a ... What is ECLS? An Introduction to Extracorporeal Life Support. University of Michigan Health System [On-line information]. ...

  15. Charge separation sensitized by advanced II-VI semiconductor nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Kelley, David F. [Univ.of California, Merced, CA (United States)

    2017-04-11

    This proposal focuses on how the composition and morphology of pure and alloyed II-VI semiconductor heterostructures control their spectroscopic and dynamical properties. The proposed research will use a combination of synthesis development, electron microscopy, time-resolved electronic spectroscopy and modeling calculations to study these nanostructures. The proposed research will examine the extent to which morphology, compression due to lattice mismatch and alloy effects can be used to tune the electron and hole energies and the spectroscopic properties of II-VI heterojunctions. It will also use synthesis, optical spectroscopy and HRTEM to examine the role of lattice mismatch and hence lattice strain in producing interfacial defects, and the extent to which defect formation can be prevented by controlling the composition profile through the particles and across the interfaces. Finally, we will study the magnitude of the surface roughness in core/shell nanostructures and the role of shell thickness variability on the inhomogeneity of interfacial charge transfer rates.

  16. Distributed decay kinetics of charge separated state in solid film

    NARCIS (Netherlands)

    Lehtivuori, Heli; Efimov, Alexander; Lemmetyinen, Helge; Tkachenko, Nikolai V.

    2007-01-01

    Photoinduced electron transfer in solid films of porphyrin-fullerene dyads was studied using femtosecond pump-probe method. The relaxation of the main photo-product, intramolecular exciplex, was found to be essentially non-exponential. To analyze the decays a model accounting for a distribution of

  17. Mechanism for efficient photoinduced charge separation at disordered organic heterointerfaces

    Energy Technology Data Exchange (ETDEWEB)

    Eersel, Harm van; Janssen, Rene A.J.; Kemerink, Martijn [Eindhoven University of Technology, Department of Applied Physics, Eindhoven (Netherlands)

    2012-07-10

    Despite the poor screening of the Coulomb potential in organic semiconductors, excitons can dissociate efficiently into free charges at a donor-acceptor heterojunction, leading to application in organic solar cells. A kinetic Monte Carlo model that explains this high efficiency as a two-step process is presented. Driven by the band offset between donor and acceptor, one of the carriers first hops across the interface, forming a charge transfer (CT) complex. Since the electron and hole forming the CT complex have typically not relaxed within the disorder-broadened density of states (DOS), their remaining binding energy can be overcome by further relaxation in the DOS. The model only contains parameters that are determined from independent measurements and predicts dissociation yields in excess of 90% for a prototypical heterojunction. Field, temperature, and band offset dependencies are investigated and found to be in agreement with earlier experiments. Whereas the investigated heterojunctions have substantial energy losses associated with the dissociation process, these results suggest that it is possible to reach high dissociation yields at low energy loss. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Amenorrhea - primary

    Science.gov (United States)

    ... of periods - primary Images Primary amenorrhea Normal uterine anatomy (cut section) Absence of menstruation (amenorrhea) References Bulun SE. The physiology and pathology of the female reproductive axis. In: ...

  19. Magnuson-Stevens Fishery Conservation Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Magnuson-Stevens Fishery Conservation and Management Act (MSA) is the primary law governing marine fisheries management in U.S. federal waters. It has since been...

  20. Self-acting shaft seals

    Science.gov (United States)

    Ludwig, L. P.

    1978-01-01

    Self-acting seals are described in detail. The mathematical models for obtaining a seal force balance and the equilibrium operating film thickness are outlined. Particular attention is given to primary ring response (seal vibration) to rotating seat face runout. This response analysis reveals three different vibration models with secondary seal friction being an important parameter. Leakage flow inlet pressure drop and affects of axisymmetric sealing face deformations are discussed. Experimental data on self-acting face seals operating under simulated gas turbine conditions are given. Also a spiral groove seal design operated to 244 m/sec (800 ft/sec) is described.

  1. Atomic Energy Commission Act, 2000 (Act 588)

    International Nuclear Information System (INIS)

    2000-01-01

    Act 588 of the Republic of Ghana entitled, Atomic Energy Commission Act, 2000, amends and consolidates the Atomic Energy Commission Act, 204 of 1963 relating to the establishment of the Atomic Energy Commission. Act 588 makes provision for the Ghana Atomic Energy Commission to establish more institutes for the purpose of research in furtherance of its functions and also promote the commercialization of its research and development results. (E.A.A.)

  2. ACT-R Electronic Bookshelf: An Adaptive System To Support Learning ACT-R on the Web.

    Science.gov (United States)

    Brusilovsky, Peter; Anderson, John

    This paper describes the electronic ACT-R Bookshelf, a system which supports learning ACT-R, a well-known theory in the field of cognitive psychology, over the World Wide Web. ACT-R Bookshelf is a collection of electronic books on various aspects of ACT-R. The primary role of ACT-R Bookshelf is to serve as a 24-hour information resource for…

  3. Primary explosives

    Energy Technology Data Exchange (ETDEWEB)

    Matyas, Robert; Pachman, Jiri [Pardubice Univ. (Czech Republic). Faculty of Chemical Technology

    2013-06-01

    The first chapter provides background such as the basics of initiation and differences between requirements on primary explosives used in detonators and igniters. The authors then clarify the influence of physical characteristics on explosive properties, focusing on those properties required for primary explosives. Furthermore, the issue of sensitivity is discussed. All the chapters on particular groups of primary explosives are structured in the same way, including introduction, physical and chemical properties, explosive properties, preparation and documented use.

  4. Primary fibromyalgia

    DEFF Research Database (Denmark)

    Jacobsen, S; Jensen, L T; Foldager, M

    1990-01-01

    Serum concentrations of procollagen type III aminoterminal peptide have previously been reported to be low in some patients with primary fibromyalgia and the aim of this study was to determine if such patients differ clinically from primary fibromyalgia patients with normal levels of procollagen...... type III aminoterminal peptide. Subjective symptoms, tender points and dynamic muscle strength in 45 women with primary fibromyalgia were related to serum concentrations of procollagen type III aminoterminal peptide. Patients with low serum concentrations of procollagen type III aminoterminal peptide...... concentrations of procollagen type III aminoterminal peptide of primary fibromyalgia patients are connected to the disease impact....

  5. Nuclear Regulatory Authority Act, 2015 (Act 895)

    International Nuclear Information System (INIS)

    2015-04-01

    An Act to establish a Nuclear Regulatory Authority in Ghana. This Act provides for the regulation and management of activities and practices for the peaceful use of nuclear material or energy, and to provide for the protection of persons and the environment against the harmful effects of radiation; and to ensure the effective implementation of the country’s international obligations and for related matters. This Act replaced the Radiation Protection Instrument, of 1993 (LI 1559).

  6. the relationship between primary school teachers extrinsic

    African Journals Online (AJOL)

    PROF EKWUEME

    Primary School Teachers Motivation Questionnaire (PSTMQ) and objective test items in English Language, Mathematics and Primary Science to measure students' performance. ... Mathematics and Primary Science. ... teachers as those who mediate pupils learning and act as facilitators ..... Students' perception of teacher- ...

  7. Atomic Act amended

    International Nuclear Information System (INIS)

    Drabova, D.

    2002-01-01

    In the paper by the chairwoman of the Czech nuclear regulatory authority, the history of Czech nuclear legislation is outlined, the reasons for the amendment of the Atomic Act (Act No. 18/1997) are explained, and the amendments themselves are highlighted. The Act No. 13/2002 of 18 December 2001 is reproduced from the official Collection of Acts of the Czech Republic in the facsimile form. The following acts were thereby amended: Atomic Act No. 18/1997, Metrology Act No. 505/1990, Public Health Protection Act No. 258/2000, and Act No. 2/1969 on the Establishment of Ministries and Other Governmental Agencies of the Czech Republic. (P.A.)

  8. Exploring how different modes of governance act across health system levels to influence primary healthcare facility managers' use of information in decision-making: experience from Cape Town, South Africa.

    Science.gov (United States)

    Scott, Vera; Gilson, Lucy

    2017-09-15

    Governance, which includes decision-making at all levels of the health system, and information have been identified as key, interacting levers of health system strengthening. However there is an extensive literature detailing the challenges of supporting health managers to use formal information from health information systems (HISs) in their decision-making. While health information needs differ across levels of the health system there has been surprisingly little empirical work considering what information is actually used by primary healthcare facility managers in managing, and making decisions about, service delivery. This paper, therefore, specifically examines experience from Cape Town, South Africa, asking the question: How is primary healthcare facility managers' use of information for decision-making influenced by governance across levels of the health system? The research is novel in that it both explores what information these facility managers actually use in decision-making, and considers how wider governance processes influence this information use. An academic researcher and four facility managers worked as co-researchers in a multi-case study in which three areas of management were served as the cases. There were iterative cycles of data collection and collaborative analysis with individual and peer reflective learning over a period of three years. Central governance shaped what information and knowledge was valued - and, therefore, generated and used at lower system levels. The central level valued formal health information generated in the district-based HIS which therefore attracted management attention across the levels of the health system in terms of design, funding and implementation. This information was useful in the top-down practices of planning and management of the public health system. However, in facilities at the frontline of service delivery, there was a strong requirement for local, disaggregated information and experiential

  9. Primary productivity

    Digital Repository Service at National Institute of Oceanography (India)

    Verlecar, X.N.; Parulekar, A.H.

    Photosynthetic production in the oceans in relation to light, nutrients and mixing processes is discussed. Primary productivity in the estuarine region is reported to be high in comparison to coastal and oceanic waters. Upwelling phenomenon...

  10. Primary Hyperparathyroidism

    Science.gov (United States)

    ... Neoplasia Type 1 Thyroid Disease & Pregnancy Primary Hyperparathyroidism Prolactinoma National Hormone and Pituitary Program (NHPP): Information for ... qualified health care provider nearby. Eating, Diet, and Nutrition Eating, diet, and nutrition have not been shown ...

  11. Primary Myelofibrosis

    Science.gov (United States)

    ... attack is higher. Patients also have an increased risk of acute myeloid leukemia or primary myelofibrosis . Symptoms of polycythemia vera include headaches and a feeling of fullness below the ribs on the left ...

  12. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Therapeutics Lab Developing New Treatments The CF Foundation offers a number of resources for learning about clinical ... her father: Demonstrate and discuss common ACT therapies Offer their tips for fitting ACTs into daily life ...

  13. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Treatments and Therapies Airway Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your airways. ... or caregiver. Older kids and adults can choose ACTs that they can do on their own. Share ...

  14. Self-acting and hydrodynamic shaft seals

    Science.gov (United States)

    Ludwig, L. P.

    1973-01-01

    Self-acting and hydrodynamic seals are described. The analytical procedures are outlined for obtaining a seal force balance and the operating film thickness. Particular attention is given to primary ring response (seal vibration) to rotating seat face runout. This response analysis revealed three different vibration modes. Proposed applications of self-acting seals in gas turbine engines and in rocket vehicle turbopumps are described. Also experimental data on self-acting face seals operating under simulated gas turbine conditions are given; these data show the feasibility of operating the seal at conditions of 345 newtons per square centimeter (500 psi) and 152 meters per second (500 ft/sec) sliding speed.

  15. Nuclear Installations Act 1965

    International Nuclear Information System (INIS)

    1965-01-01

    This Act governs all activities related to nuclear installations in the United Kingdom. It provides for the licensing procedure for nuclear installations, the duties of licensees, the competent authorities and carriers of nuclear material in respect of nuclear occurrences, as well as for the system of third party liability and compensation for nuclear damage. The Act repeals the Nuclear Installations (Licensing and Insurance) Act 1959 and the Nuclear Installations (Amendment Act) 1965 except for its Section 17(2). (NEA) [fr

  16. [Hypertension: once primary, always primary?

    NARCIS (Netherlands)

    Braam, R.L.; Pieters, G.F.F.M.; Thien, Th.

    2002-01-01

    Three patients diagnosed with primary hypertension suddenly developed hard-to-treat blood pressure after several years of stable blood pressure. One patient, a man aged 48 years, had developed a renal artery stenosis, which had not been present five years earlier. The other two patients, a man aged

  17. Hyperthyroidism (primary)

    OpenAIRE

    Nygaard, Birte

    2010-01-01

    Hyperthyroidism is characterised by high levels of serum thyroxine and triiodothyronine, and low levels of thyroid-stimulating hormone (TSH). Thyrotoxicosis is the clinical effect of high levels of thyroid hormones, whether or not the thyroid gland is the primary source.The main causes of hyperthyroidism are Graves' disease, toxic multinodular goitre, and toxic adenoma.About 20 times more women than men have hyperthyroidism.

  18. Radioactive Substances Act 1960

    International Nuclear Information System (INIS)

    1960-01-01

    This Act regulates the keeping and use of radioactive material and makes provision for the disposal and storage of radioactive waste in the United Kingdom. It provides for a licensing system for such activities and for exemptions therefrom, in particular as concerns the United Kingdom Atomic Energy Authority. The Act repeals Section 4(5) of the Atomic Energy Authority Act, 1954 which made temporary provision for discharge of waste on or from premises occupied by the Authority. (NEA) [fr

  19. Learning dialog act processing

    OpenAIRE

    Wermter, Stefan; Löchel, Matthias

    1996-01-01

    In this paper we describe a new approach for learning dialog act processing. In this approach we integrate a symbolic semantic segmentation parser with a learning dialog act network. In order to support the unforeseeable errors and variations of spoken language we have concentrated on robust data-driven learning. This approach already compares favorably with the statistical average plausibility method, produces a segmentation and dialog act assignment for all utterances in a robust manner,...

  20. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Reform Could Impact People With CF The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy Achievements Advocacy News Briefings, Testimonies, and Regulatory ...

  1. Radiological Protection Act 1970

    International Nuclear Information System (INIS)

    1970-01-01

    This Act provides for the establishment of a Radiological Protection Board to undertake research and advise on protection from radiation hazards. Its functions include provision of advice to Government departments with responsibilities in relation to protection of sectors of the community or the community as a whole against the hazards of ionizing radiation. The Act, which lays down that the Board shall replace certain departments concerned with radiation protection, repeals several Sections of the Radioactive Substances Act 1948 and the Science and Technology Act 1965. (NEA) [fr

  2. 25 CFR 700.33 - Act (The Act).

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Act (The Act). 700.33 Section 700.33 Indians THE OFFICE OF NAVAJO AND HOPI INDIAN RELOCATION COMMISSION OPERATIONS AND RELOCATION PROCEDURES General Policies and Instructions Definitions § 700.33 Act (The Act). (a) The Act. The Act is Pub. L. 93-531, (88 Stat...

  3. 16 CFR 316.3 - Primary purpose.

    Science.gov (United States)

    2010-01-01

    ....3 Primary purpose. (a) In applying the term “commercial electronic mail message” defined in the CAN-SPAM Act, 15 U.S.C. 7702(2), the “primary purpose” of an electronic mail message shall be deemed to be... does not intend for these criteria to treat as a “commercial electronic mail message” anything that is...

  4. Are primary care physicians equipped enough to act as first ...

    African Journals Online (AJOL)

    Background: Prompt and appropriate management of dental trauma has been shown to significantly improve the prognosis of the resulting injuries in numerous cases. Frequently it is other health professionals that provide emergency care following traumatic dental injuries including tooth avulsion. The objective of this study ...

  5. Marine Mammal Protection Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Marine Mammal Protection Act (MMPA or Act) prohibits, with certain exceptions, the "take" of marine mammals in U.S. waters and by U.S. citizens on the high seas,...

  6. Collective speech acts

    NARCIS (Netherlands)

    Meijers, A.W.M.; Tsohatzidis, S.L.

    2007-01-01

    From its early development in the 1960s, speech act theory always had an individualistic orientation. It focused exclusively on speech acts performed by individual agents. Paradigmatic examples are ‘I promise that p’, ‘I order that p’, and ‘I declare that p’. There is a single speaker and a single

  7. Americans with Disabilities Act.

    Science.gov (United States)

    Kaesberg, Mary Ann; Murray, Kenneth T.

    1994-01-01

    Presents a 35-item checklist of practical activities for school district compliance with the Americans with Disabilities Act (ADA). The checklist is based on ADA statutes, other civil rights legislation and litigation, as well as pertinent regulations and the legislative history of the act contained in the Congressional Record. (MLF)

  8. Radiation emitting devices act

    International Nuclear Information System (INIS)

    1970-01-01

    This Act, entitled the Radiation Emitting Devices Act, is concerned with the sale and importation of radiation emitting devices. Laws relating to the sale, lease or import, labelling, advertising, packaging, safety standards and inspection of these devices are listed as well as penalties for any person who is convicted of breaking these laws

  9. Nuclear Installations Act 1969

    International Nuclear Information System (INIS)

    1969-01-01

    The purpose of this Act is to amend the Nuclear Installations Act 1965 to bring it into full compliance with the international conventions on nuclear third party liability to which the United Kingdom is a Signatory, namely, the Paris Convention, the Brussels Supplementary Convention and the Vienna Convention. (NEA) [fr

  10. The Radiation Protection Act

    International Nuclear Information System (INIS)

    Persson, L.

    1989-01-01

    The new Radiation Protection Act (1988:220) entered into force in Sweden on July 1st, 1988. This book presents the Act as well as certain regulations connected to it. As previously, the main responsibility for public radiation protection will rest with one central radiation protection authority. According to the 1988 Act, the general obligations with regard to radiation protection will place a greater responsibility than in the past on persons carrying out activities involving radiation. Under the act, it is possible to adjust the licensing and supervisory procedures to the level of danger of the radiation source and the need for adequate competence, etc. The Act recognises standardised approval procedures combined with technical regulations for areas where the risks are well known. The Act contains several rules providing for more effective supervision. The supervising authority may in particular decide on the necessary regulations and prohibitions for each individual case. The possibilities of using penal provisions have been extended and a rule on the mandatory execution of orders has been introduced. The Ordinance on Radiation Protection (1988:293) designates the National Institute of Radiation Protection (SSI) as the central authority referred to in the Radiation Protection Act. The book also gives a historic review of radiation protection laws in Sweden, lists regulations issued by SSI and presents explanations of radiation effects and international norms in the area. (author)

  11. Canada's Clean Air Act

    International Nuclear Information System (INIS)

    2006-01-01

    This paper provided an outline of Canada's Clean Air Act and examined some of the regulatory changes that will occur as a result of its implementation. The Act is being introduced to strengthen the legislative basis for taking action on reducing air pollution and GHGs, and will allow the government to regulate both indoor and outdoor air pollutants and GHGs. The Act will require the Ministers of the Environment and Health to establish national air quality objectives, as well as to monitor and report on their attainment. The Canadian Environmental Protection Act will be amended to enable the government to regulate the blending of fuels and their components. The Motor Vehicle Fuel Consumption Standards Act will also be amended to enhance the government's authority to regulate vehicle fuel efficiency. The Energy Efficiency Act will also be expanded to allow the government to set energy efficiency standards and labelling requirements for a wider range of consumer and commercial products. The Act will commit to short, medium and long-term industrial air pollution targets. Regulations will be proposed for emissions from industry; on-road and off-road vehicles and engines; and consumer and commercial products. It was concluded that the Government of Canada will continue to consult with provinces, territories, industries and Canadians to set and reach targets for the reduction of both indoor and outdoor air pollutants and GHG emissions. 6 figs

  12. The Energy Act 1983

    International Nuclear Information System (INIS)

    1983-01-01

    Part II of This Act came into force on 1 September 1983 and is concerned with nuclear installations. Its main purpose is to amend the Nuclear Installations Act 1965 to give effect to the provisions of two Protocols amending the Paris Convention on nuclear third party liability and the Brussels Convention Supplementary to the Paris Convention respectively. The principal effect of these modifications is to increase the sums available to meet claims for nuclear damage. The United Kingdom is a Party to both Conventions and the provisions of the 1983 Act will enable it to ratify the Protocols. (NEA) [fr

  13. Abandoned Shipwreck Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data represents the extent of the Abandoned Shipwreck Act (ASA). The ASA allows states to manage a broad range of resources within submerged lands, including...

  14. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy ... the value of tapping into the expertise that only people with CF and their families have. We invite you to share insights to ...

  15. Energy Policy Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Energy Policy Act (EPA) addresses energy production in the United States, including: (1) energy efficiency; (2) renewable energy; (3) oil and gas; (4) coal; (5)...

  16. ACTS – SUCCESS STORY

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. ACTS – SUCCESS STORY. Totally 103 experiments were conducted and the programme succeeded in the areas. Medicine; Education; Defence; Emergency Response; Maritime and Aeronautical Mobile Communications; Science and Astronomy.

  17. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... There are different ways to clear your airways. Most are easy to do. Infants and toddlers will ... best ACT is the one that you are most likely to perform as part of your daily ...

  18. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... to loosen mucus from airway walls. See how different airway clearance techniques work to help you clear the thick, sticky mucus ... Offer their tips for fitting ACTs into daily life Airway Clearance Techniques | Webcast ... Facebook Twitter ...

  19. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... CF Community in Health Care Reform Milestones in Health Care Reform How Tax Reform Could Impact People With CF The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy Achievements ...

  20. Clean Water Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent geographic terms used within the Clean Water Act (CWA). The CWA establishes the basic structure for regulating the addition of pollutants...

  1. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... toddlers will need help from a parent or caregiver. Older kids and adults can choose ACTs that ... into the smaller airways to attack bacteria. Choose What's Best for You Your respiratory therapist or another ...

  2. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... that help thin and move the mucus, and antibiotics. Bronchodilators should be inhaled before you start ACTs. This medication helps to widen your airways (bronchi) by relaxing the ...

  3. Endangered Species Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of the Endangered Species Act (ESA) is to protect and recover imperiled species and the ecosystems upon which they depend. The U.S. Fish and Wildlife...

  4. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Reform Could Impact People With CF The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy Achievements ... on their own. Share Facebook Twitter Email More options Print Share Facebook Twitter Email Print Permalink All ...

  5. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... 3-D Structure Consortium CFTR Folding Consortium Epithelial Stem Cell Consortium Mucociliary Clearance Consortium SUCCESS WITH THERAPIES RESEARCH ... ACTs involve coughing or huffing . Many of them use percussion (clapping) or vibration to loosen mucus from ...

  6. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... today. ANNUAL FUND Become a Corporate Supporter Cause Marketing Make a Charitable Gift Our Corporate Supporters Workplace ... Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your airways. Most are easy to ...

  7. Marine Pollution Prevention Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Marine Pollution Prevention Act of 2008 implements the International Convention for the Prevention of Pollution from Ships, including related Protocols (MARPOL)...

  8. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... CF Community in Health Care Reform Milestones in Health Care Reform How Tax Reform Could Impact People With CF The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy Achievements Advocacy News Briefings, Testimonies, and Regulatory ...

  9. Preventive Radiation Protection Act

    International Nuclear Information System (INIS)

    Roewer, H.

    1988-01-01

    The commentary is intended to contribute to protection of the population by a practice-oriented discussion and explanation of questions arising in connection with the Preventive Radiation Protection Act. Leaving aside discussions about abandonment of nuclear power, or criticism from any legal point of view, the commentary adopts the practical approach that accepts, and tries to help implementing, the act as it is. It is a guide for readers who are not experts in the law and gives a line of orientation by means of explanations and sometimes by citations from other acts (in footnotes). The commentary also presents the EURATOM Directive No. 3954/87 dated 22 December 1987, the EC Directive No. 3955/87 dated 22 December 1987, and the EC Directive No. 1983/88 dated 5 July 1988. A tabular survey shows the system of duties and competences defined by the Preventive Radiation Protection Act. (RST) [de

  10. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Contraception and Protection How Does CF Affect the Female Reproductive System? How Does CF Affect the Male ... Reform Could Impact People With CF The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy Achievements ...

  11. ACT250 Districts

    Data.gov (United States)

    Vermont Center for Geographic Information — The ACT 250 Districts layer is part of a larger dataset that contains administrative boundaries for Vermont's Agency of Natural Resources. The dataset includes...

  12. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... ACTs involve coughing or huffing . Many of them use percussion (clapping) or vibration to loosen mucus from airway walls. See how different airway clearance techniques work to help you clear the thick, sticky mucus ...

  13. Acts of Research

    DEFF Research Database (Denmark)

    Nelund, Sidsel

    place mostly in seminars and articles, in which knowledge is often discussed as an intrinsic quality of the artwork. Acts of Research, however, is devoted to studying the rise of knowledge production in contemporary art from the perspective of artistic, curatorial and educational research...... described as knowledge producers and exhibitions and art works as instances of knowledge production. Acts of Research: Knowledge Production in Contemporary Arts between Knowledge Economy and Critical Practices analyses this development. The academic discussion of knowledge production in the arts has taken...... with an awareness of larger political, economic, geographical and art-related aspects. The concept of ‘acts of research’ is suggested as a way to understand knowledge production as a creative act in which research carried out in relation to a specific material challenges and resists the protocols of conventional...

  14. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Congressional Cystic Fibrosis Caucus Our Policy Agenda Policy Principles SIGN UP FOR ADVOCACY ACTION ALERTS Community We ... options Print Share Facebook Twitter Email Print Permalink All ACTs involve coughing or huffing . Many of them ...

  15. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... How Does CF Affect the Male Reproductive System? Sex and CF: Some Practical Advice Family Planning and ... need help from a parent or caregiver. Older kids and adults can choose ACTs that they can ...

  16. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... FOR ADVOCACY ACTION ALERTS Community We recognize the value of tapping into the expertise that only people ... ACTs involve coughing or huffing . Many of them use percussion (clapping) or vibration to loosen mucus from ...

  17. National Environmental Policy Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Environmental Policy Act (NEPA) was the first major environmental law in the United States and established national environmental policies for the...

  18. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Reform Could Impact People With CF The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy Achievements ... Board of Trustees Our Leadership Careers Reports and Financials Contact Us Governance and Policies What is CF? ...

  19. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... own. Share Facebook Twitter Email More options Print Share Facebook Twitter Email Print Permalink All ACTs involve ... CF Care Team Research About Our Research Developing New Treatments Researcher Resources Assistance Services Find Resources: CF ...

  20. Affordable Care Act (ACA)

    Data.gov (United States)

    Social Security Administration — The Affordable Care Act (ACA) is a federal statute enacted with a goal of increasing the quality and affordability of health insurance. Through a web service, CMS...

  1. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy Achievements Advocacy News Briefings, Testimonies, and Regulatory Comments Congressional Cystic Fibrosis Caucus Our Policy Agenda Policy Principles SIGN UP FOR ADVOCACY ACTION ...

  2. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... people with cystic fibrosis so that they make smart decisions about CF-related research, treatment, and access ... The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy Achievements Advocacy News Briefings, Testimonies, and Regulatory ...

  3. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... What to Consider Regarding a Lung Transplant Medications Antibiotics Bronchodilators CFTR Modulator Therapies Mucus Thinners Nebulizer Care ... that help thin and move the mucus, and antibiotics. Bronchodilators should be inhaled before you start ACTs. ...

  4. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... resources you need to continuously build upon this work. Awards and Grants Career Development Awards Research Awards ... The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy Achievements Advocacy News Briefings, Testimonies, and Regulatory ...

  5. The Corporations Act 2001

    OpenAIRE

    Bostock, Tom

    2002-01-01

    The author outlines reforms made in Australia in the area of company law with an analysis of the Corporations Act 2001, which along with the Australian Securities and Investments Commission Act 2001 comprises Corporations legislation in Australia. Article by Tom Bostock (a partner in the law firm Mallesons Stephen Jaques, Melbourne, Australia). Published in Amicus Curiae - Journal of the Institute of Advanced Legal Studies and its Society for Advanced Legal Studies. The Journal is produced by...

  6. Outer Continental Shelf Lands Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data represents geographic terms used within the Outer Continental Shelf Lands Act (OCSLA or Act). The Act defines the United States outer continental shelf...

  7. No 592 - Radiation Act

    International Nuclear Information System (INIS)

    1991-01-01

    This Act will enter into force on 1 January 1992. The scope of the Act is extensive as, in addition to ionizing radiation, it will also apply to activities involving exposure to natural radiation and non-ionizing radiation. Its purpose is to prevent and restrict harmful effects to health resulting from radiation. The basic principles of the Act are that the practice involving radiation should be justified; radiation protection should be optimized; and radiation doses should be as low as reasonably achievable. Licensed organisations using radiation will be responsible for the safety of the activity involving exposure to radiation and for having available the appropriate expertise to this effect. The required so-called safety licence provides the regulatory control to ensure that radiation is used sensibly, that the equipment and shields are technically acceptable and the operating personnel is competent, and that the radioactive waste is dealt with appropriately. The Radiation Act will also apply to nuclear activities within the scope of the 1987 Nuclear Energy Act [fr

  8. The Clean Air Act

    International Nuclear Information System (INIS)

    Coburn, L.L.

    1990-01-01

    The Clean Air Act amendments alter the complex laws affecting atmospheric pollution and at the same time have broad implications for energy. Specifically, the Clean Air Act amendments for the first time deal with the environmental problem of acid deposition in a way that minimizes energy and economic impacts. By relying upon a market-based system of emission trading, a least cost solution will be used to reduce sulfur dioxide (SO 2 ) emissions by almost 40 percent. The emission trading system is the centerpiece of the Clean Air Act (CAA) amendments effort to resolve energy and environmental interactions in a manner that will maximize environmental solutions while minimizing energy impacts. This paper will explore how the present CAA amendments deal with the emission trading system and the likely impact of the emission trading system and the CAA amendments upon the electric power industry

  9. ST–ACTS

    DEFF Research Database (Denmark)

    Gidofalvi, Gyozo; Pedersen, Torben Bach

    2006-01-01

    hot issue in the area of spatio–temporal databases [7]. While existing Moving Object Simulators (MOSs) address different physical aspects of mobility, they neglect the important social and geo–demographical aspects of it. This paper presents ST–ACTS, a Spatio–Temporal ACTivity Simulator that, using...... various geo–statistical data sources and intuitive principles, models the so far neglected aspects. ST–ACTS considers that (1) objects (representing mobile users) move from one spatio–temporal location to another with the objective of performing a certain activity at the latter location; (2) not all users...

  10. Atomic Energy Act 1989

    International Nuclear Information System (INIS)

    1989-05-01

    This Act, which entered into force on 1 september 1989, contains a series of provisions dealing with different subjects: increase of public financing for British Nuclear Fuels plc, amendment of the Nuclear Installations Act 1965 regarding the powers of the Health and Safety Executive to recover expenses directly from nuclear operators and obligation of the UKAEA to take out insurance or other financial security to cover its liability and finally, measures to enable the UK to ratify the IAEA Convention on Assistance in Case of a Nuclear Accident or Radiological Emergency [fr

  11. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... NACFC Carolyn and C Richard Mattingly Leadership in Mental Health Care Award Mary M. Kontos Award NACFC Reflections ... CF Community in Health Care Reform Milestones in Health Care Reform How Tax Reform Could ... Act Our Advocacy Work Advocacy Achievements ...

  12. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Team Your cystic fibrosis care team includes a group of CF health care professionals who partner with ... Awards and Grants Career Development Awards Research Awards Training Awards CF ... Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your ...

  13. "Act in Good Faith."

    Science.gov (United States)

    McKay, Robert B.

    1979-01-01

    It is argued that the Supreme Court's Bakke decision overturning the University of California's minority admissions program is good for those who favor affirmative action programs in higher education. The Supreme Court gives wide latitude for devising programs that take race and ethnic background into account if colleges are acting in good faith.…

  14. Atomic Energy Control Act

    International Nuclear Information System (INIS)

    1970-01-01

    This act provides for the establishment of the Atomic Energy Control Board. The board is responsible for the control and supervision of the development, application and use of atomic energy. The board is also considered necessary to enable Canada to participate effectively in measures of international control of atomic energy

  15. Special Appropriation Act Projects

    Science.gov (United States)

    EPA is sometimes directed to provide funding to a specific entity for study, purpose, or activity.This information will be of interest to a community or other entity that has been identified in one of EPA's appropriations acts to receive such funding.

  16. Radioactive Substances Act 1948

    International Nuclear Information System (INIS)

    1948-01-01

    This Act regulates the use of radioactive substances and radiation producing devices in the United Kingdom. It provides for the control of import, export, sale, supply etc. of such substances and devices and lays down the safety regulations to be complied with when dealing with them. (NEA) [fr

  17. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Reform Could Impact People With CF The Preserving Employee Wellness Programs Act Our Advocacy Work Advocacy Achievements ... AWARENESS Tomorrow’s Leaders About Us News Blog Chapters Facebook Twitter YouTube Instagram Email DONATE Breadcrumb Navigation Home ...

  18. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Practical Advice Family Planning and Parenting With CF Making Your Family Planning Decisions Pregnancy and CF Alternative Ways to Build a ... with cystic fibrosis so that they make smart decisions about CF-related research, treatment, and access to care. ... Act Our Advocacy Work Advocacy Achievements ...

  19. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... programs and policies to improve the lives of people with CF. Help us by raising awareness of CF, participating in a fundraising event, or volunteering ... clear your airways. Most are easy to do. Infants and toddlers will need help from a parent or caregiver. Older kids and adults can choose ACTs that they ...

  20. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... and Their Families When There's More Than One Person With CF in the Same School Daily Life ... Awards and Grants Career Development Awards Research Awards Training Awards CF ... Clearance Airway Clearance Techniques (ACTs) There are different ways to clear your ...

  1. Ocean Dumping Control Act

    International Nuclear Information System (INIS)

    1975-01-01

    This Act provides for the control of dumping of wastes and other substances in the ocean in accordance with the London Convention of 1972 on Prevention of Marine Pollution by the Dumping of Wastes and other Matter to which Canada is a Party. Radioactive wastes are included in the prohibited and restricted substances. (NEA)

  2. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... to try. However, the best ACT is the one that you are most likely to perform as part of your daily treatment plan. Watch the webcast below to hear a respiratory therapist, a child with CF and her father: Demonstrate and discuss ...

  3. The Child Justice Act

    African Journals Online (AJOL)

    Stephan

    1995-06-16

    Jun 16, 1995 ... Gallinetti "Child Justice" 648; Le Roux-Kemp 2008 Annual Survey of South African Law 298 (the. Act contains a "separate, but parallel, ... The various aspects of section 68 are then evaluated. The greatest challenges lie in the ... See also, eg, Picardi Hotels v Thekwini. Properties 2009 1 SA 493 (SCA) para ...

  4. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Data Requests Get Involved X close Advocate Our goal is to educate policy makers about the needs ... Reform Could Impact People With CF The Preserving Employee Wellness Programs Act Our Advocacy ... Assistance Services Find Resources: CF Foundation Compass Insurance Get ...

  5. Airway Clearance Techniques (ACTs)

    Medline Plus

    Full Text Available ... Offer their tips for fitting ACTs into daily life Airway Clearance Techniques | Webcast To learn more about how you can help your infant or child manage their lung health, watch parents of children with CF and a respiratory therapist ...

  6. Non-innocent side-chains with dipole moments in organic solar cells improve charge separation

    NARCIS (Netherlands)

    de Gier, Hilde D.; Broer, Ria; Havenith, Remco W. A.

    2014-01-01

    Providing sustainable energy is one of the biggest challenges nowadays. An attractive answer is the use of organic solar cells to capture solar energy. Recently a promising route to increase their efficiency has been suggested: developing new organic materials with a high dielectric constant. This

  7. Photochemical charges separation and photoelectric properties of flexible solar cells with two types of heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiangyang, E-mail: lxy081276@126.com, E-mail: yzgu@henu.edu.cn; Wang, Shun; Zheng, Haiwu; Cheng, Xiuying; Gu, Yuzong, E-mail: lxy081276@126.com, E-mail: yzgu@henu.edu.cn [Institute of Microsystems Physics and School of Physics and Electronics, Henan University, Kaifeng 475004 (China)

    2015-12-14

    Photochemical charges generation, separation, and transport at nanocrystal interfaces are central to energy conversion for solar cells. Here, Zn{sub 2}SnO{sub 4} nanowires/Cu{sub 4}Bi{sub 4}S{sub 9} (ZTO/CBS), ZTO nanowires/CBS-reduced graphene oxide (ZTO/CBS-RGO), and bulk heterojunction (BHJ) solar cells were measured. The signals of steady state and electric field-induced surface photovoltage indicate that RGO with high electron mobility can evidently improve the photovoltaic response. Besides, ZTO/CBS and ZTO/CBS-RGO cells exhibit the excellent performance and the highest efficiencies of 1.2% and 2.8%, respectively. The internal relations of photoelectric properties to some factors, such as film thickness, direct paths, RGO conductive network, energy level matching, etc., were discussed in detail. Qualitative and quantitative analyses further verified the comprehensive effect of RGO and other factors. Importantly, the fine bendable characteristic of BHJ solar cells with excellent efficiency and facile, scalable production gives the as-made flexible solar cells device potential for practical application in future.

  8. Anisotropic Metal Deposition on TiO2 Particles by Electric-Field-Induced Charge Separation.

    Science.gov (United States)

    Tiewcharoen, Supakit; Warakulwit, Chompunuch; Lapeyre, Veronique; Garrigue, Patrick; Fourier, Lucas; Elissalde, Catherine; Buffière, Sonia; Legros, Philippe; Gayot, Marion; Limtrakul, Jumras; Kuhn, Alexander

    2017-09-11

    Deposition of metals on TiO 2 semiconductor particles (M-TiO 2 ) results in hybrid Janus objects combining the properties of both materials. One of the techniques proposed to generate Janus particles is bipolar electrochemistry (BPE). The concept can be applied in a straightforward way for the site-selective modification of conducting particles, but is much less obvious to use for semiconductors. Herein we report the bulk synthesis of anisotropic M-TiO 2 particles based on the synergy of BPE and photochemistry, allowing the intrinsic limitations, when they are used separately, to be overcome. When applying electric fields during irradiation, electrons and holes can be efficiently separated, thus breaking the symmetry of particles by modifying them selectively and in a wireless way on one side with either gold or platinum. Such hybrid materials are an important first step towards high-performance designer catalyst particles, for example for photosplitting of water. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Transition Metal Polypyridine Complexes: Studies of Mediation in Dye-Sensitized Solar Cells and Charge Separation

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, C. Michael [Colorado State Univ., Fort Collins, CO (United States). Dept. of Chemistry; Prieto, Amy L. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Chemistry

    2017-02-08

    The Elliott group has long been supported by DOE for studies of cobalt(II/III) trisbypiridine (DTB) mediator complexes in dye sensitized solar cells. Previous work demonstrated that Co(II/III) chemistry is sensitive to the environment, showing unprecedented electrode-surface and electrolyte dependant voltammetry. In electrolytes that have large lipophilic cations, voltammetry of the [Co(DTB)3]2+/3+ couple is nearly Nernstian in appearance on nominally oxide-free metal surfaces. In contrast, on semiconductor electrodes in electrolytes with small, hard cations such as Li+, the electron transfer rates are so slow that it is difficult to measure any Faradaic current even at overpotentials of ±1 V. These studies are of direct relevance to the operation of cobalt-based mediators in solar cells. The research has also shown that these mediators are compatible with copper phenantroline based dyes, in contrast to I- due to the insolubility of CuI.

  10. Integration of Semiconducting Sulfides for Full-Spectrum Solar Energy Absorption and Efficient Charge Separation.

    Science.gov (United States)

    Zhuang, Tao-Tao; Liu, Yan; Li, Yi; Zhao, Yuan; Wu, Liang; Jiang, Jun; Yu, Shu-Hong

    2016-05-23

    The full harvest of solar energy by semiconductors requires a material that simultaneously absorbs across the whole solar spectrum and collects photogenerated electrons and holes separately. The stepwise integration of three semiconducting sulfides, namely ZnS, CdS, and Cu2-x S, into a single nanocrystal, led to a unique ternary multi-node sheath ZnS-CdS-Cu2-x S heteronanorod for full-spectrum solar energy absorption. Localized surface plasmon resonance (LSPR) in the nonstoichiometric copper sulfide nanostructures enables effective NIR absorption. More significantly, the construction of pn heterojunctions between Cu2-x S and CdS leads to staggered gaps, as confirmed by first-principles simulations. This band alignment causes effective electron-hole separation in the ternary system and hence enables efficient solar energy conversion. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Charge separation in photoinitiated electron transfer reactions induced by a polyelectrolyte

    International Nuclear Information System (INIS)

    Meyerstein, D.; Rabani, J.; Matheson, M.S.; Meisel, D.

    1978-01-01

    When uncharged molecules quench the luminescence of Ru(bpy) 3 /sup 2+*/ by electron transfer to the quencher, the addition of poly(vinyl sulfate) (PVS) may, through its potential field, affect the rate of quenching, enhance the net separated charge yield, and slow the back reaction of the separated photoredox products. In all such cases that we have studied the quenching rate in the presence of PVS was reduced to about 60% of the rate measured in the absence of PVS. For two neutral species, iron(III) nitrilotriacetate (FeNTA) and cobalt(III) acetylacetonate (Co(acac) 3 ), photoreduction of the quencher was observed, and the redox yield escaping geminate recombination was substantially increased by added PVS. In the case of FeNTA the rate of the bulk back reaction was not changed appreciably by the presence of PVS owing to the rapid neutralization of Fe(NTA) - by protonation. For Co(acac) 3 the rate of the bulk back reaction was decreased by several orders of magnitude and the back reaction was shown to occur via the enolate form of the ligand which is released to the bulk solution. 4 figures, 4 tables

  12. Charge separation in excitonic and bipolar solar cells - A detailed balance approach

    International Nuclear Information System (INIS)

    Kirchartz, Thomas; Rau, Uwe

    2008-01-01

    A generalized solar cell model for excitonic and classical, bipolar solar cells is developed that describes the combined transport and interaction of electrons, holes and excitons. Both, conventional inorganic solar cells as well as organic solar cells, where excitons play a dominant role for energy transport, turn out to be special cases of this model. Due to the inclusion of photon recycling effects, the approach is compatible with the principle of detailed balance and the Shockley-Queisser limit. We show how varying the interaction between excitons and charge carriers as well as varying the respective mobilities of the different species changes the operation mode of the solar cell path between excitonic and bipolar

  13. Enhanced Charge Separation Efficiency in Pyridine-Anchored Phthalocyanine-Sensitized Solar Cells by Linker Elongation.

    Science.gov (United States)

    Ikeuchi, Takuro; Agrawal, Saurabh; Ezoe, Masayuki; Mori, Shogo; Kimura, Mutsumi

    2015-11-01

    A series of zinc phthalocyanine sensitizers (PcS22-24) having a pyridine anchoring group are designed and synthesized to investigate the structural dependence on performance in dye-sensitized solar cells. The pyridine-anchor zinc phthalocyanine sensitizer PcS23 shows 79 % incident-photon to current-conversion efficiency (IPCE) and 6.1 % energy conversion efficiency, which are comparable with similar phthalocyanine dyes having a carboxylic acid anchoring group. Based on DFT calculations, the high IPCE is attributed with the mixture of an excited-state molecular orbital of the sensitizer and the orbitals of TiO2 . Between pyridine and carboxylic acid anchor dyes, opposite trends are observed in the linker-length dependence of the IPCE. The red-absorbing PcS23 is applied for co-sensitization with a carboxyl-anchor organic dye D131 that has a complementary spectral response. The site-selective adsorption of PcS23 and D131 on the TiO2 surface results in a panchromatic photocurrent response for the whole visible-light region of sun light. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Early Bacteriopheophytin Reduction in Charge Separation in Reaction Centers of Rhodobacter sphaeroides

    NARCIS (Netherlands)

    Zhu, J.; van Stokkum, I.H.M.; Paparelli, L.; Jones, M.R.; Groot, M.L.

    2013-01-01

    A question at the forefront of biophysical sciences is, to what extent do quantum effects and protein conformational changes play a role in processes such as biological sensing and energy conversion? At the heart of photosynthetic energy transduction lie processes involving ultrafast energy and

  15. Nonlinear waves in electron-positron-ion plasmas including charge separation

    Science.gov (United States)

    Mugemana, A.; Moolla, S.; Lazarus, I. J.

    2017-02-01

    Nonlinear low-frequency electrostatic waves in a magnetized, three-component plasma consisting of hot electrons, hot positrons and warm ions have been investigated. The electrons and positrons are assumed to have Boltzmann density distributions while the motion of the ions are governed by fluid equations. The system is closed with the Poisson equation. This set of equations is numerically solved for the electric field. The effects of the driving electric field, ion temperature, positron density, ion drift, Mach number and propagation angle are investigated. It is shown that depending on the driving electric field, ion temperature, positron density, ion drift, Mach number and propagation angle, the numerical solutions exhibit waveforms that are sinusoidal, sawtooth and spiky. The introduction of the Poisson equation increased the Mach number required to generate the waveforms but the driving electric field E 0 was reduced. The results are compared with satellite observations.

  16. Is electric charge separation the main process for kinetic energy transformation into the meteor phenomenon?

    Czech Academy of Sciences Publication Activity Database

    Spurný, Pavel; Ceplecha, Zdeněk

    2008-01-01

    Roč. 489, č. 1 (2008), s. 449-454 ISSN 0004-6361 R&D Projects: GA ČR GA205/08/0411 Grant - others:EU(XE) MRTN-CT-2006-035519 Institutional research plan: CEZ:AV0Z10030501 Keywords : meteors * meteoroids Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.153, year: 2008

  17. Direct observation of ultrafast long-range charge separation at polymer–fullerene heterojunctions

    KAUST Repository

    Provencher, Franç oise; Bé rubé , Nicolas; Parker, Anthony W.; Greetham, Gregory M.; Towrie, Michael; Hellmann, Christoph; Cô té , Michel; Stingelin, Natalie; Silva, Carlos; Hayes, Sophia C.

    2014-01-01

    In polymeric semiconductors, charge carriers are polarons, which means that the excess charge deforms the molecular structure of the polymer chain that hosts it. This results in distinctive signatures in the vibrational modes of the polymer. Here, we probe polaron photogeneration dynamics at polymer:fullerene heterojunctions by monitoring its time-resolved resonance-Raman spectrum following ultrafast photoexcitation. We conclude that polarons emerge within 300 fs. Surprisingly, further structural evolution on ≤50-ps timescales is modest, indicating that the polymer conformation hosting nascent polarons is not significantly different from that near equilibrium. We interpret this as suggestive that charges are free from their mutual Coulomb potential because we would expect rich vibrational dynamics associated with charge-pair relaxation. We address current debates on the photocarrier generation mechanism at molecular heterojunctions, and our work is, to our knowledge, the first direct probe of molecular conformation dynamics during this fundamentally important process in these materials. © 2014 Macmillan Publishers Limited. All rights reserved.

  18. Direct observation of ultrafast long-range charge separation at polymer–fullerene heterojunctions

    KAUST Repository

    Provencher, Françoise

    2014-07-01

    In polymeric semiconductors, charge carriers are polarons, which means that the excess charge deforms the molecular structure of the polymer chain that hosts it. This results in distinctive signatures in the vibrational modes of the polymer. Here, we probe polaron photogeneration dynamics at polymer:fullerene heterojunctions by monitoring its time-resolved resonance-Raman spectrum following ultrafast photoexcitation. We conclude that polarons emerge within 300 fs. Surprisingly, further structural evolution on ≤50-ps timescales is modest, indicating that the polymer conformation hosting nascent polarons is not significantly different from that near equilibrium. We interpret this as suggestive that charges are free from their mutual Coulomb potential because we would expect rich vibrational dynamics associated with charge-pair relaxation. We address current debates on the photocarrier generation mechanism at molecular heterojunctions, and our work is, to our knowledge, the first direct probe of molecular conformation dynamics during this fundamentally important process in these materials. © 2014 Macmillan Publishers Limited. All rights reserved.

  19. Charge-Separation Dynamics in Inorganic-Organic Ternary Blends for Efficient Infrared Photodiodes

    NARCIS (Netherlands)

    Jarzab, Dorota; Szendrei, Krisztina; Yarema, Maksym; Pichler, Stefan; Heiss, Wolfgang; Loi, Maria A.

    2011-01-01

    Knowledge about the working mechanism of the PbS:P3HT:PCBM [P3HT=poly(3-hexylthiophene), PCBM=[6,6]-phenyl-C(61) -butyric acid methyl ester] hybrid blend used for efficient near-infrared photodiodes is obtained from time-resolved photoluminescence (PL) studies. To understand the role of each

  20. Charge Separation and Recombination in Small Band Gap Oligomer-Fullerene Triads

    NARCIS (Netherlands)

    Karsten, Bram P.; Bouwer, Ricardo K. M.; Hummelen, Jan C.; Williams, Rene M.; Janssen, Rene A. J.

    2010-01-01

    Synthesis and photophysics of a series of thiophene-thienopyrazine small band gap oligomers end-capped at both ends with C(60) are presented In these triads a photoinduced electron transfer reaction occurs between the oligomer as a donor and the fullerene as an acceptor Femtosecond photoinduced

  1. Charge Separation at Mixed-Dimensional Single and Multilayer MoS2/Silicon Nanowire Heterojunctions.

    Science.gov (United States)

    Henning, Alex; Sangwan, Vinod K; Bergeron, Hadallia; Balla, Itamar; Sun, Zhiyuan; Hersam, Mark C; Lauhon, Lincoln J

    2018-05-16

    Layered two-dimensional (2-D) semiconductors can be combined with other low-dimensional semiconductors to form nonplanar mixed-dimensional van der Waals (vdW) heterojunctions whose charge transport behavior is influenced by the heterojunction geometry, providing a new degree of freedom to engineer device functions. Toward that end, we investigated the photoresponse of Si nanowire/MoS 2 heterojunction diodes with scanning photocurrent microscopy and time-resolved photocurrent measurements. Comparison of n-Si/MoS 2 isotype heterojunctions with p-Si/MoS 2 heterojunction diodes under varying biases shows that the depletion region in the p-n heterojunction promotes exciton dissociation and carrier collection. We measure an instrument-limited response time of 1 μs, which is 10 times faster than the previously reported response times for planar Si/MoS 2 devices, highlighting the advantages of the 1-D/2-D heterojunction. Finite element simulations of device models provide a detailed understanding of how the electrostatics affect charge transport in nanowire/vdW heterojunctions and inform the design of future vdW heterojunction photodetectors and transistors.

  2. TITANIUM DIOXIDE TRIADS FOR IMPROVED CHARGE-SEPARATION USING CONDUCTIVE POLYMERS

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, T.M.; Gaylor, T.N.; de la Garza, L.; Rajh, T.

    2009-01-01

    Dye-sensitized solar cells are potentially one of the best solutions to solar energy conversion because of the low cost of required materials and production processes. Titanium dioxide (TiO2) nanoparticulate fi lms are the basis for one of these types of cells, providing large surface area for dye-sensitizer adsorption. Because TiO2 nanoparticulate fi lms develop defects caused by oxygen defi ciency, deep reactive electron traps are formed. With the addition of an enediol ligand, these electron traps are deliberately removed, enhancing the conduction of electrons within the fi lm. In this project, TiO2 nanoparticulate fi lms made by a layer-by-layer dip coating method were modifi ed with 3,4-dihydroxyphenylacetic acid (DOPAC). DOPAC binds to the titanium atoms on the surface of the nanoparticles, restoring their octahedral geometry. This restructuring of the surface shifts the spectral properties of the TiO2 to the visible spectrum and improves the separation of charges which is observed using photoelectrochemistry. Furthermore, DOPAC enables the electronic attachment of other molecules to the surface of TiO2 fi lms, such as the conductive polymer polyaniline base. This conductive polymer provides an extended separation of charges which increases photocurrent production by forming a triad with the TiO2 semiconductor through the 3,4-dihydroxyphenylacetic acid linker. The photocurrent increases due to the donor properties of the conductive polymer thereby decreasing charge pair recombination.

  3. Dreams and acting out.

    Science.gov (United States)

    Grinberg, L

    1987-01-01

    Dreams can be used as containers that free patients from increased tension. This may be the principal function of certain types of dreams, called "evacuative dreams." They are dreams used for getting rid of unbearable affects and unconscious fantasies, or as a safety valve for partial discharge of instinctual drives. These dreams are observed primarily in borderline and psychotic patients, but can also be seen in the regressive states of neurotic patients during weekends and other periods of separation. Such dreams have to be differentiated from "elaborative dreams," which have a working-through function and stand in an inverse relationship to acting out: the greater the production of elaborative dreams, the less the tendency to act out, and vice versa.

  4. Atomic Energy Act 1946

    International Nuclear Information System (INIS)

    1946-01-01

    This Act provides for the development of atomic energy in the United Kingdom and for its control. It details the duties and powers of the competent Minister, in particular his powers to obtain information on and to inspect materials, plant and processes, to control production and use of atomic energy and publication of information thereon. Also specified is the power to search for and work minerals and to acquire property. (NEA) [fr

  5. Radiological protection act, 1991

    International Nuclear Information System (INIS)

    1991-01-01

    This Act provides for the establishment of the Radiological Protection Institute of Ireland and dissolves An Bord Fuinnimh Nuicleigh (the Board), transferring its assets and liabilities to the Institute. It sets out a range of radiation protection measures to be taken by various Ministers in the event of a radiological emergency and gives effect at national level to the Assistance Convention, the Early Notification Convention and the Physical Protection Convention. The Institute is the competent Irish authority for the three Conventions. (NEA) [fr

  6. Toxic Substances Control Act

    Energy Technology Data Exchange (ETDEWEB)

    1992-05-15

    This Reference Book contains a current copy of the Toxic Substances Control Act and those regulations that implement the statute and appear to be most relevant to DOE activities. The document is provided to DOE and contractor staff for informational purposes only and should not be interpreted as legal guidance. Questions concerning this Reference Book may be directed to Mark Petts, EH-231 (202/586-2609).

  7. Journal of Community Medicine and Primary Health Care - Vol 23 ...

    African Journals Online (AJOL)

    Journal of Community Medicine and Primary Health Care - Vol 23, No 1-2 (2011) ... The Nigerian National Health Bill 2011: Delay of Presidential Assent to an Act: ... Knowledge And Practice of Occupational Safety Among Quarry Workers in A ...

  8. Turkish Primary School Pupils' Views on Punishment

    Science.gov (United States)

    Aydin, Bahri

    2010-01-01

    Teachers meet with unwanted behavior when they are acting as facilitators of the learning process and they resort to certain tactics to deal with them. One of these tactics is punishment. This study aimed to identify the views held by Turkish primary school pupils on punishment. According to the results of the study, pupils were punished for…

  9. Primary production of tropical marine ecosystems

    Digital Repository Service at National Institute of Oceanography (India)

    Bhattathiri, P.M.A.

    Among tropical marine ecosystems estuaries are one of the highly productive areas and act as a nursery to large number of organisms. The primary production in most of the estuaries is less during the monsoon period. Post-monsoon period shows...

  10. Act to amend cost regulations of the Atomic Energy Act

    International Nuclear Information System (INIS)

    1980-01-01

    Article 21 is replaced by articles 21 to 21b. According to this, fees or reimbursements for expenses for official acts (e.g. decisions, supervisory acts, safeguarding of nuclear fuels) as well as for the use of facilities according to article 9a, section 3, of the Atomic Energy Act (e.g. Laender facilities to collect nuclear waste). (HP) [de

  11. DELVING INTO SPEECH ACT A Case Of Indonesian EFL Young Learners

    Directory of Open Access Journals (Sweden)

    Swastika Septiani, S.Pd

    2017-04-01

    Full Text Available This study attempts to describe the use of speech acts applied in primary school. This study is intended to identify the speech acts performed in primary school, to find the most dominant speech acts performed in elementary school, to give brief description of how speech acts applied in primary school, and to know how to apply the result of the study in English teaching learning to young learners. The speech acts performed in primary school is classified based on Searle‘s theory of speech acts. The most dominant speech acts performed in primary school is Directive (41.17%, the second speech act mostly performed is Declarative (33.33%, the third speech act mostly performed is Representative and Expressive (each 11.76%, and the least speech act performed is Commisive (1.9%. The speech acts performed in elementary school is applied on the context of situation determined by the National Education Standards Agency (BSNP. The speech acts performed in fourth grade have to be applied in the context of classroom, and the speech acts performed in fifth grade have to be applied in the context of school, whereas the speech acts performed in sixth grade have to be applied in the context of the students‘ surroundings. The result of this study is highy expected to give significant contribution to English teaching learning to young learners. By acknowledging the characteristics of young learners, the way they learn English as a foreign language, the teachers are expected to have inventive strategies and various techniques to create a fun and condusive atmosphere in English class.

  12. Teaching Speech Acts

    Directory of Open Access Journals (Sweden)

    Teaching Speech Acts

    2007-01-01

    Full Text Available In this paper I argue that pragmatic ability must become part of what we teach in the classroom if we are to realize the goals of communicative competence for our students. I review the research on pragmatics, especially those articles that point to the effectiveness of teaching pragmatics in an explicit manner, and those that posit methods for teaching. I also note two areas of scholarship that address classroom needs—the use of authentic data and appropriate assessment tools. The essay concludes with a summary of my own experience teaching speech acts in an advanced-level Portuguese class.

  13. The Experiment as Act

    DEFF Research Database (Denmark)

    Søndergaard, Morten

    In December 1965, an experiment took place at The Independent Art Space in Copenhagen (Den Frie Kunstbygning). Short named POEX65, it was looking to create and activate POetry EXperiments across artistic genres and formats (thus, in essence, making a POetry EXposition). The POEX65 event framed many...... to be able to analyse the phenomena found at POEX65. Here I will use the notion of the ‘ontological theatre’ (Pickering), which, according to Pickering, is acted out in experimental art productions. The experiment could thus be seen as an ‘agency-realism’ – as an ‘act’ of relations across the aesthetics...

  14. Atomic Energy Authority Act 1954

    International Nuclear Information System (INIS)

    1954-01-01

    This Act provides for the setting up of an Atomic Energy Authority for the United Kingdom. It also makes provision for the Authority's composition, powers, duties, rights and liabilities, and may amend, as a consequence of the establishment of the Authority and in connection therewith, the Atomic Energy Act, 1946, the Radioactive Substances Act 1948 and other relevant enactments. (NEA) [fr

  15. 76 FR 59073 - Privacy Act

    Science.gov (United States)

    2011-09-23

    ... CENTRAL INTELLIGENCE AGENCY 32 CFR Part 1901 Privacy Act AGENCY: Central Intelligence Agency. ACTION: Proposed rule. SUMMARY: Consistent with the Privacy Act (PA), the Central Intelligence Agency...-1379. SUPPLEMENTARY INFORMATION: Consistent with the Privacy Act (PA), the CIA has undertaken and...

  16. CONSTRUCTION CONTRACTS ACT (2013): IMPLICATIONS OF THE ACT FOR THE PRACTICING QUANTITY SURVEYOR. A COMPANY BASED INVESTIGATION

    OpenAIRE

    Byrne, Roy

    2017-01-01

    Abstract The Construction Contracts Act 2013 was introduced into the Irish construction industry for the primary benefit of the sub-contractors, and to address their exposure to the poor payment practices that were prevalent in the industry. The Act was introduced in the Seanad by Senator Feargal Quinn in May 2010, as a private member’s bill. It was enacted on 29th July 2013 and recently came into effect on the 25th July 2016. The Act seeks to regulate payments under construction contra...

  17. Structuring Payment to Medical Homes After the Affordable Care Act

    OpenAIRE

    Edwards, Samuel T.; Abrams, Melinda K.; Baron, Richard J.; Berenson, Robert A.; Rich, Eugene C.; Rosenthal, Gary E.; Rosenthal, Meredith B.; Landon, Bruce E.

    2014-01-01

    The Patient-Centered Medical Home (PCMH) is a leading model of primary care reform, a critical element of which is payment reform for primary care services. With the passage of the Affordable Care Act, the Accountable Care Organization (ACO) has emerged as a model of delivery system reform, and while there is theoretical alignment between the PCMH and ACOs, the discussion of physician payment within each model has remained distinct. Here we compare payment for medical homes with that for acco...

  18. Applying organizational behavior theory to primary care.

    Science.gov (United States)

    Mullangi, Samyukta; Saint, Sanjay

    2017-03-01

    Addressing the mounting primary care shortage in the United States has been a focus of educators and policy makers, especially with the passage of the Affordable Care Act in 2010 and the Medicare Access and CHIP Reauthorization Act in 2015, placing increased pressure on the system. The Association of American Medical Colleges recently projected a shortage of as many as 65,000 primary care physicians by 2025, in part because fewer than 20% of medical students are picking primary care for a career. We examined the issue of attracting medical students to primary care through the lens of organizational behavior theory. Assuming there are reasons other than lower income potential for why students are inclined against primary care, we applied various principles of the Herzberg 2-factor theory to reimagine the operational flow and design of primary care. We conclude by proposing several solutions to enrich the job, such as decreasing documentation requirements, reducing the emphasis on specialty consultations, and elevating physicians to a supervisory role.

  19. Validation of a McKinney-Vento Act Implementation Scale

    Science.gov (United States)

    Canfield, James P.; Teasley, Martell L.; Abell, Neil; Randolph, Karen A.

    2012-01-01

    Objective: The McKinney-Vento Act (MVA) is the primary federal policy addressing homelessness in America with specific mandates designed to ameliorate the effects homelessness has on educational attainment for school-age children. The extent to which this policy is implemented may have far-reaching effects for homeless children. The MVA…

  20. Acting to gain information

    Science.gov (United States)

    Rosenchein, Stanley J.; Burns, J. Brian; Chapman, David; Kaelbling, Leslie P.; Kahn, Philip; Nishihara, H. Keith; Turk, Matthew

    1993-01-01

    This report is concerned with agents that act to gain information. In previous work, we developed agent models combining qualitative modeling with real-time control. That work, however, focused primarily on actions that affect physical states of the environment. The current study extends that work by explicitly considering problems of active information-gathering and by exploring specialized aspects of information-gathering in computational perception, learning, and language. In our theoretical investigations, we analyzed agents into their perceptual and action components and identified these with elements of a state-machine model of control. The mathematical properties of each was developed in isolation and interactions were then studied. We considered the complexity dimension and the uncertainty dimension and related these to intelligent-agent design issues. We also explored active information gathering in visual processing. Working within the active vision paradigm, we developed a concept of 'minimal meaningful measurements' suitable for demand-driven vision. We then developed and tested an architecture for ongoing recognition and interpretation of visual information. In the area of information gathering through learning, we explored techniques for coping with combinatorial complexity. We also explored information gathering through explicit linguistic action by considering the nature of conversational rules, coordination, and situated communication behavior.

  1. 76 FR 72878 - Financial Crimes Enforcement Network; Amendment to the Bank Secrecy Act Regulations-Imposition of...

    Science.gov (United States)

    2011-11-28

    ... Iran as a Jurisdiction of Primary Money Laundering Concern AGENCY: Financial Crimes Enforcement Network... Republic of Iran (``Iran'') is a jurisdiction of primary money laundering concern pursuant to 31 U.S.C... Act amends the anti- money laundering provisions of the Bank Secrecy Act (``BSA''), codified at 12 U.S...

  2. The Price-Anderson Act

    International Nuclear Information System (INIS)

    Jones, R.

    2000-01-01

    The Price-Anderson Act establishes nuclear liability law in the United States. First passed in 1957, it has influenced other nuclear liability legislation around the world. The insurer response the nuclear accident at Three Mile Island in 1979 demonstrates the application of the Act in a real life situation. The Price-Anderson Act is scheduled to be renewed in 2002, and the future use of commercial nuclear power in tge United States will be influenced by this renewal. (author)

  3. The new Swiss Energy Act

    International Nuclear Information System (INIS)

    Tami, R.

    1999-01-01

    The new Swiss Energy Act and the accompanying regulation enable the instructions given in the poll by the electorate in 1990 -- the Energy Article in the Swiss Constitution -- to be implemented. The Energy Act creates the necessary basis for an advanced and sustainable energy policy. It should contribute to a sufficient, broadly based, dependable, economical and environment-friendly energy supply. The Energy Act and the Energy Regulation entered into force on January 1, 1999. (author)

  4. Atomic Energy Authority Act 1971

    International Nuclear Information System (INIS)

    1971-01-01

    This Act provides for the transfer of property, rights, liabilities and obligations of parts of the undertaking of the United Kingdom Atomic Energy Autority, to two new Compagnies set up for this purpose: the Bristish Nuclear Fuels Limited, and the Radiochemical Centre Limited. Patents licences and registered designs owned by the Autority at the time of the transfer are not included therein. The Act also includes amendments to the Nuclear Installations Act 1965, notably as regards permits to operate granted to a body corporate. Finally, the Schedule to this Act lays down a certain number of provisions relating to security and the preservation of secrets. (NEA) [fr

  5. [Euthanasia and medical act].

    Science.gov (United States)

    2011-05-01

    Right to life -as the prohibition of intentionally and arbitrarily taking life, even with authorization of the concerned one- is an internationally recognized right. In many countries, debate regarding euthanasia is more centered in its convenience, social acceptability and how it is regulated, than in its substantial legitimacy. Some argue that euthanasia should be included as part of clinical practice of health professionals, grounded on individual's autonomy claims-everyone having the liberty to choose how to live and how to die. Against this, others sustain that life has a higher value than autonomy, exercising autonomy without respecting the right to life would become a serious moral and social problem. Likewise, euthanasia supporters some-times claim a 'right to live with dignity', which must be understood as a personal obligation, referred more to the ethical than to the strictly legal sphere. In countries where it is already legalized, euthanasia practice has extended to cases where it is not the patient who requests this but the family or some healthcare professional, or even the legal system-when they think that the patient is living in a condition which is not worthy to live. Generalization of euthanasia possibly will end in affecting those who need more care, such as elder, chronically ill or dying people, damaging severely personal basic rights. Nature, purpose and tradition of medicine rule out the practice of euthanasia, which ought not be considered a medical act or legitimately compulsory for physicians. Today's medicine counts with effective treatments for pain and suffering, such as palliative care, including sedative therapy, which best preserves persons dignity and keeps safe the ethos of the medical profession.

  6. Primary Progressive Aphasia

    Science.gov (United States)

    ... which cause different symptoms. Semantic variant primary progressive aphasia Symptoms include these difficulties: Comprehending spoken or written ... word meanings Naming objects Logopenic variant primary progressive aphasia Symptoms include: Having difficulty retrieving words Frequently pausing ...

  7. Brain tumor - primary - adults

    Science.gov (United States)

    ... Vestibular schwannoma (acoustic neuroma) - adults; Meningioma - adults; Cancer - brain tumor (adults) ... Primary brain tumors include any tumor that starts in the brain. Primary brain tumors can start from brain cells, ...

  8. Primary ovarian malignant melanoma

    Directory of Open Access Journals (Sweden)

    Kostov Miloš

    2010-01-01

    Full Text Available Background. Primary ovarian malignant melanoma is extremely rare. It usually appears in the wall of a dermoid cyst or is associated with another teratomatous component. Metastatic primary malignant melanoma to ovary from a primary melanoma elsewhere is well known and has been often reported especially in autopsy studies. Case report. We presented a case of primary ovarian malignant melanoma in a 45- year old woman, with no evidence of extraovarian primary melanoma nor teratomatous component. The tumor was unilateral, macroscopically on section presented as solid mass, dark brown to black color. Microscopically, tumor cells showed positive immunohistochemical reaction for HMB-45, melan-A and S-100 protein, and negative immunoreactivity for estrogen and progesteron receptors. Conclusion. Differentiate metastatic melanoma from rare primary ovarian malignant melanoma, in some of cases may be a histopathological diagnostic problem. Histopathological diagnosis of primary ovarian malignant melanoma should be confirmed by immunohistochemical analyses and detailed clinical search for an occult primary tumor.

  9. Investigating Primary Source Literacy

    Science.gov (United States)

    Archer, Joanne; Hanlon, Ann M.; Levine, Jennie A.

    2009-01-01

    Primary source research requires students to acquire specialized research skills. This paper presents results from a user study testing the effectiveness of a Web guide designed to convey the concepts behind "primary source literacy". The study also evaluated students' strengths and weaknesses when conducting primary source research. (Contains 3…

  10. 7 CFR 65.100 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Act. 65.100 Section 65.100 Agriculture Regulations of... MARKETING ACT OF 1946 AND THE EGG PRODUCTS INSPECTION ACT (CONTINUED) COUNTRY OF ORIGIN LABELING OF BEEF..., AND GINSENG General Provisions Definitions § 65.100 Act. Act means the Agricultural Marketing Act of...

  11. Nuclear Material (Offences) Act 1983

    International Nuclear Information System (INIS)

    1983-01-01

    The main purpose of this Act is to enable the United Kingdom to ratify the Convention on the Physical Protection of Nuclear Material which opened for signature at Vienne and New York on 3 March 1980. The Act extends throughout the United Kingdom. (NEA) [fr

  12. Nurse Reinvestment Act. Public Law.

    Science.gov (United States)

    Congress of the U.S., Washington, DC.

    This document contains the text of the Nurse Reinvestment Act, which amends the Public Health Service Act to address the increasing shortage of registered nurses by instituting a series of policies to improve nurse recruitment and nurse retention. Title I details two initiatives to boost recruitment of nurses. The first initiative includes the…

  13. Online Challenge versus Offline ACT

    Science.gov (United States)

    Peckham, Irvin

    2010-01-01

    This article compares essays written in response to the ACT Essay prompt and a locally developed prompt used for placement. The two writing situations differ by time and genre: the ACT Essay is timed and argumentative; the locally developed is untimed and explanatory. The article analyzes the differences in student performance and predictive…

  14. Nuclear industry (Finance) Act 1981

    International Nuclear Information System (INIS)

    1981-01-01

    The purpose of the Act is to enable British Nuclear Fuels Limited to make borrowings backed by Government guarantees in order to finance its ten year investment programme. More specifically, the Act raises the financial limit applicable to British Nuclear Fuels Limited from pound 500 million to pound 1,000 million. (NEA) [fr

  15. 78 FR 46256 - Privacy Act

    Science.gov (United States)

    2013-07-31

    ... FEDERAL ELECTION COMMISSION 11 CFR Part 1 Privacy Act CFR Correction In Title 11 of the Code of Federal Regulations, revised as of January 1, 2012, on page 5, in Sec. 1.2, the words ``95 and 96 of the Internal Revenue Code of 1954.'' are added at the end of the definition of Act. [FR Doc. 2013-18535 Filed 7...

  16. Atomic Energy Commission Act, 1963

    International Nuclear Information System (INIS)

    1963-01-01

    Promulgated in 1963, the Atomic Energy Commission Act (204) established and vested in the Ghana Atomic Energy Commission the sole responsibility for all matters relating to the peaceful uses of atomic energy in the country. Embodied in the Act are provisions relating to the powers, duties, rights and liabilities of the Commission. (EAA)

  17. Primary Hyperparathyroidism: An Overview

    Directory of Open Access Journals (Sweden)

    Jessica MacKenzie-Feder

    2011-01-01

    Full Text Available Primary hyperparathyroidism is a common condition that affects 0.3% of the general population. Primary and tertiary care specialists can encounter patients with primary hyperparathyroidism, and prompt recognition and treatment can greatly reduce morbidity and mortality from this disease. In this paper we will review the basic physiology of calcium homeostasis and then consider genetic associations as well as common etiologies and presentations of primary hyperparathyroidism. We will consider emerging trends in detection and measurement of parathyroid hormone as well as available imaging modalities for the parathyroid glands. Surgical indications and approach will be reviewed as well as medical management of primary hyperparathyroidism with bisphosphonates and calcimimetics.

  18. Normocalcemic Primary Hyperparathyroidism

    Science.gov (United States)

    Cusano, Natalie E.; Silverberg, Shonni J.; Bilezikian, John P.

    2013-01-01

    Primary hyperparathyroidism, a common endocrine disorder, is traditionally defined by hypercalcemia and elevated levels of parathyroid hormone (PTH). A newer presentation of primary hyperparathyroidism has been described over the past decade, in which PTH is elevated but serum calcium is consistently normal, in the absence of secondary causes of hyperparathyroidism, such as renal disease or vitamin D deficiency. Recognition of this phenotype of primary hyperparathyroidism, normocalcemic primary hyperparathyroidism, supports a biphasic chronological time course in some individuals in which PTH levels are first elevated but serum calcium is normal, followed by the development of frank hypercalcemia. This review focuses on the available literature regarding this newly described phenotype of primary hyperparathyroidism. PMID:23374739

  19. Linking FRRF Derived Photophysiology with Carbon-based Primary Productivity: Insights from Concepts of Cellular Energy Allocation

    Science.gov (United States)

    Schuback, N.; Schallenberg, C.; Duckham, C.; Flecken, M.; Maldonado, M. T.; Tortell, P. D.

    2016-02-01

    Active chlorophyll a fluorescence approaches, including fast repetition rate fluorometry (FRRF), have the potential to provide estimates of phytoplankton primary productivity at unprecedented spatial and temporal resolution. FRRF-derived productivity rates are based on estimates of charge separation in photosystem II (ETRRCII), which must be converted into ecologically relevant units of carbon fixation. Understanding sources of variability in the coupling of ETRRCII and carbon fixation provides important physiological insight into phytoplankton photosynthesis, and is critical for the application of FRRF as a primary productivity measurement tool. We present data from a series of experiments during which we simultaneously measured phytoplankton carbon fixation and ETRRCII in the iron-limited NE subarctic Pacific. Our results show significant variability of the derived conversion factor (Ve:C/nPSII), with highest values observed under conditions of excess excitation pressure at the level of photosystem II, caused by high light and/or low iron. Our results will be discussed in the context of metabolic plasticity, which evolved in phytoplankton to simultaneously maximize growth and provide photoprotection under fluctuating light and limiting nutrient availabilities. Because the derived conversion factor is associated with conditions of excess light, it correlates with the expression of non-photochemical quenching (NPQ) in the pigment antenna, also derived from FRRF measurements. Our results demonstrate a significant correlation between NPQ and the conversion factor Ve:C/nPSII, and the potential of this relationship to improve FRRF-based estimates of phytoplankton carbon fixation rates is discussed.

  20. Ten Years of the Workforce Investment Act (WIA): Interpreting the Research on WIA and Related Programs

    Science.gov (United States)

    Decker, Paul T.; Berk, Jillian A.

    2011-01-01

    In 1998, President Clinton signed the federal Workforce Investment Act (WIA). Implemented in 2000, WIA replaced the Job Partnership Training Act (JTPA) as the primary federal job training program. Congress viewed WIA as a way to end "business as usual" in the workforce investment system. WIA aimed to transform the employment and training…

  1. Capacitação de profissionais da atenção primária à saúde para educação em Diabetes Mellitus Capacitación, de profesionales que actúan en la atención primaria a la salud, en educación en Diabetes Mellitus Training of professionals, acting in primary health care, in Diabetes Mellitus education

    Directory of Open Access Journals (Sweden)

    Heloisa de Carvalho Torres

    2010-01-01

    fisiopatología y en las pruebas complementarias de la enfermedad. Los talleres ayudaron a despertar el potencial de reflexión, de crítica y de creatividad de los profesionales, que se necesita para cambiar el proceso educativo. Fue considerada una estrategia pedagógica, fácil de entender, interactiva y lúdica. CONCLUSIONES: Los talleres contribuyeron para la planificación del proceso educativo y la estructuración de un modelo de evaluación de las prácticas de promoción de la salud y de la educación en diabetes.OBJECTIVE: To present the proposal of educational workshops on diabetes and a strategy of evaluation aimed at upgrading the professionals' performance in primary care. METHODS: The workshops were implemented using participatory methodology, play techniques, experiences, and group dynamics, involving the participation of 85 health professionals from Units of Primary Care, in the city of Belo Horizonte, MG. The knowledge about the disease and the skills required for self-care were measured by applying specific instruments. The workshops were evaluated based on the instrument developed for that purpose. RESULTS: There were limitations in the knowledge of professionals about pathophysiology and the disease's complementary tests. The workshops helped to awaken the potential of professionals (reflection, criticism and creativity necessary to change the educational process. It was considered a pedagogical strategy, easy to understand, interactive and playful. CONCLUSIONS: The workshops contributed to the planning of the educational process and the structuring of an evaluation model of practices of health and education promotion in diabetes.

  2. Act local, think global

    International Nuclear Information System (INIS)

    Lewis, Chris; McRoberts, Doug

    2002-01-01

    Tip O'Neill, one of the grand old men of modem US politics, once famously remarked that all politics is local. Like most politicians who succeed on the national stage - and not just in the US - it was a truth he never lost sight of. What is true for politicians is equally true in the communications business. We may increasingly live in a global village, but successful companies - even multi-nationals - forget the importance of local and regional public relations at their peril. Think of Douglas Ivester, the CEO of Coca-Cola at the time of the 1999 Belgian contamination scandal, who allegedly reacted to first reports of the crisis by asking: 'Where the hell is Belgium?' A more appropriate question today - several years after Coke's share price toppled and the CEO was unceremoniously sacked - might be: 'Who the hell is Douglas Nester?' But - to adapt another famous phrase - the fact that communications (and marketing) professionals still need to 'act local' as much as ever before should not blind us to the growing need to 'think global'. In the nuclear industry, as in the world economy generally, increasing global integration is a reality, as are the international nature of the news media and the increasingly global nature of the anti-nuclear pressure groups. Indeed, it was the growing need for a truly global information network to counter these trends, by increasing the overall speed and accuracy of the worldwide nuclear information flow, that led the nuclear community to establish NucNet in 1991. So where exactly is the line between local and regional nuclear communications on the one hand, and global communications on the other? Is there one spin for a regional audience, and another for a global audience? This presentation proposes some guiding principles, by examining the response of nuclear communicators world-wide to the new communications agenda imposed in the wake of the September 11th suicide attacks in the US. NucNet President Doug McRoberts and Executive

  3. Generation of reactive oxygen species in the anterior eye segment. Synergistic codrugs of N-acetylcarnosine lubricant eye drops and mitochondria-targeted antioxidant act as a powerful therapeutic platform for the treatment of cataracts and primary open-angle glaucoma

    Directory of Open Access Journals (Sweden)

    Mark A. Babizhayev

    2016-12-01

    Mitochondrial targeting of compounds with universal types of antioxidant activity represents a promising approach for treating a number of ROS-related ocular diseases of the aging eye and can be implicated in the management of cataracts and primary open-angle glaucoma.

  4. Federal Technology Transfer Act (FTTA)

    Science.gov (United States)

    EPA's Federal Technology Transfer Act (FTTA) is a mechanism with which EPA can patent its inventions and license them to companies, through which innovative technologies can enter the marketplace to improve the environment and human health.

  5. Endangered Species Act Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Critical habitat (CH) is designated for the survival and recovery of species listed as threatened or endangered under the Endangered Species Act (ESA). Critical...

  6. Multiple primary cancer

    International Nuclear Information System (INIS)

    Jung, Gyu Sik; Lee, Ouk; Kim, So Sun; Kim, Ho Joon; Chun, Byung Hee; Joh, Young Duck

    1989-01-01

    It is rare for one human being to be afflicted with more than one cancer. However with further advances in therapeutic regimens, histopathologic observation, diagnostic modalities, and increased curiosity, there are increasing number of case reports of multiple primary cancer. The present study evaluates 25 histologically confirmed cases of multiple primary cancer from 1974 to 1988 at Kosin Medical Center. The most frequent site of the first primary cancer in male was stomach and in female, uterine cervix. The first primary cancer in female occurred in endocrine-related organs (breast, uterus and thyroid) in 63.6 percent. Synchronous cancers are diagnosed simultaneously or within an interval of about six months and synchronous cancers were 16 out of 25 cases. Metachronous cancers are diagnosed at interval of more than six months. There were 9 metachronous cancers and average interval between the first and second primary cancer was 22.8 months. The incidence of multiple primary cancer was 0.11 percent. The average age was 51.9 years at the time of the first primary cancer (53.1 years in male and 50.3 years in female). CT scan was most helpful in early detection of multiple primary cancers facilitating biopsy and surgery. Multiple primary cancers are beyond the medical curiosity. Early diagnosis of the disease and careful follow-up study, based on an awareness of the possibility of second cancers, will substantially increase the survival of these patients

  7. Healing Arts Radiation Protection Act

    International Nuclear Information System (INIS)

    1984-07-01

    The Healing Arts Radiation Protection Act is concerned with regulating the registration, installation, operation, inspection and safety of X-ray machines. The Act provides for the establishment of the Healing Arts Radiation Protection Commission which is responsible for reporting on all the above matters to the Ontario Minister of Health. In addition the board is responsible for the continuing development of an X-ray safety code and for the submission of an annual report of their activities to the minister

  8. Atomic Energy Authority Act 1986

    International Nuclear Information System (INIS)

    1986-01-01

    Under this Act the UKAEA is given power to borrow so that it can finance its capital expenditure programme, and will undertake a debt to the Secretary of State for Energy representing its assets. Power is given for the Government to guarantee such borrowing. The UKAEA has been organised financially on the basis of a trading fund. The Act came into force on 1 April 1986. (NEA) [fr

  9. 7 CFR 956.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 956.2 Section 956.2 Agriculture Regulations of... OF SOUTHEAST WASHINGTON AND NORTHEAST OREGON Definitions § 956.2 Act. Act means Public Act No. 10... Agreement Act of 1937, as amended (Sec. 1-19, 48 Stat. 31, as amended; 7 U.S.C. 601 et seq.). ...

  10. 7 CFR 983.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 983.2 Section 983.2 Agriculture Regulations of... NEW MEXICO Definitions § 983.2 Act. Act means Public Act No. 10, 73rd Congress (May 12, 1933), as amended and as re-enacted and amended by the Agricultural Marketing Order Act of 1937, as amended (48 Stat...

  11. 7 CFR 930.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 930.1 Section 930.1 Agriculture Regulations of... Definitions § 930.1 Act. Act means Public Act No. 10, 73d Congress (May 12, 1933), as amended, and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (48 Stat. 31, as...

  12. 7 CFR 984.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 984.2 Section 984.2 Agriculture Regulations of... Handling Definitions § 984.2 Act. Act means Public Act No. 10, 73d Congress, as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (7 U.S.C. 601 et seq.). ...

  13. 7 CFR 925.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 925.2 Section 925.2 Agriculture Regulations of... SOUTHEASTERN CALIFORNIA Definitions § 925.2 Act. Act means Public Act No. 10, 73d Congress (May 12, 1933), as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (48...

  14. 7 CFR 917.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 917.2 Section 917.2 Agriculture Regulations of... Order Regulating Handling Definitions § 917.2 Act. Act means Public Act No. 10, 73d Congress (May 12, 1933), as amended, and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as...

  15. 7 CFR 915.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 915.2 Section 915.2 Agriculture Regulations of... Regulating Handling Definitions § 915.2 Act. Act means Public Act No. 10, 73d Congress (May 12, 1933), as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (48...

  16. 7 CFR 959.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 959.2 Section 959.2 Agriculture Regulations of... Handling Definitions § 959.2 Act. Act means Public Act No. 10, 73d Congress, as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (sections 1-19, 48 Stat...

  17. 7 CFR 1260.128 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1260.128 Section 1260.128 Agriculture... Promotion and Research Order Definitions § 1260.128 Act. Act means the Beef Promotion and Research Act of 1985, Title XVI, Subtitle A of the Food Security Act of 1985, Pub. L. 99-198 and any amendments thereto. ...

  18. 7 CFR 982.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 982.2 Section 982.2 Agriculture Regulations of... Order Regulating Handling Definitions § 982.2 Act. Act means Public Act No. 10, 73d Congress, as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (7 U.S.C...

  19. 7 CFR 932.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 932.2 Section 932.2 Agriculture Regulations of... Handling Definitions § 932.2 Act. Act means Public Act No. 10, 73d Congress (May 12, 1933) as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (48 Stat. 31...

  20. 7 CFR 981.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 981.2 Section 981.2 Agriculture Regulations of... Handling Definitions § 981.2 Act. Act means Public Act No. 10, 73d Congress, as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (48 Stat. 31, as amended...

  1. 7 CFR 906.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 906.2 Section 906.2 Agriculture Regulations of... GRANDE VALLEY IN TEXAS Order Regulating Handling Definitions § 906.2 Act. Act means Public Act No. 10, 73d Congress, as amended and as re-enacted and amended by the Agricultural Marketing Agreement Act of...

  2. 7 CFR 966.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 966.2 Section 966.2 Agriculture Regulations of... Handling Definitions § 966.2 Act. Act means Public Act No. 10, 73d Congress, as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (48 Stat. 31, as amended...

  3. 7 CFR 916.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 916.2 Section 916.2 Agriculture Regulations of... Regulating Handling Definitions § 916.2 Act. Act means Public Act No. 10, 73d Congress (May 12, 1933), as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (48...

  4. 7 CFR 993.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 993.2 Section 993.2 Agriculture Regulations of... Regulating Handling Definitions § 993.2 Act. Act means Public Act No. 10, 73d Congress, as amended and reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (7 U.S.C. 601 et seq.). ...

  5. 7 CFR 35.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Act. 35.1 Section 35.1 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices... Definitions § 35.1 Act. Act or Export Grape and Plum Act means “An Act to promote the foreign trade of the...

  6. 7 CFR 923.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 923.2 Section 923.2 Agriculture Regulations of... IN WASHINGTON Order Regulating Handling Definitions § 923.2 Act. Act means Public Act No. 10, 73d... Act of 1937, as amended (48 Stat. 31, as amended; 7 U.S.C. 601 et seq.; 68 Stat. 906, 1047). ...

  7. 7 CFR 927.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 927.2 Section 927.2 Agriculture Regulations of... Regulating Handling Definitions § 927.2 Act. Act means Public Act No. 10, 73d Congress (May 12, 1933), as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (48...

  8. 7 CFR 946.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 946.2 Section 946.2 Agriculture Regulations of... Regulating Handling Definitions § 946.2 Act. Act means Public Act No. 10, 73d Congress, as amended and reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (48 Stat. 31, as...

  9. 7 CFR 989.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 989.2 Section 989.2 Agriculture Regulations of... CALIFORNIA Order Regulating Handling Definitions § 989.2 Act. Act means Public Act No. 10, 73d Congress, as amended, and as re-enacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended...

  10. 7 CFR 1170.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Act. 1170.2 Section 1170.2 Agriculture Regulations of... Orders; Milk), DEPARTMENT OF AGRICULTURE DAIRY PRODUCT MANDATORY REPORTING § 1170.2 Act. Act means the Agricultural Marketing Act of 1946, 7 U.S.C. 1621 et seq., as amended by the Dairy Market Enhancement Act of...

  11. 7 CFR 987.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 987.2 Section 987.2 Agriculture Regulations of... RIVERSIDE COUNTY, CALIFORNIA Order Regulating Handling Definitions § 987.2 Act. Act means Public Act No. 10, 73d Congress, as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of...

  12. 7 CFR 948.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 948.2 Section 948.2 Agriculture Regulations of... Regulating Handling Definitions § 948.2 Act. Act means Public Act No. 10 73d Congress, as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (sections 1-19, 48...

  13. 7 CFR 922.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 922.2 Section 922.2 Agriculture Regulations of... WASHINGTON Order Regulating Handling Definitions § 922.2 Act. Act means Public Act No. 10, 73d Congress (May 12, 1933), as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of...

  14. 7 CFR 33.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices... AUTHORITY OF THE EXPORT APPLE ACT Definitions § 33.1 Act. Act and Export Apple Act are synonymous and mean “An act to promote the foreign trade of the United States in apples to protect the reputation of...

  15. Enhanced primary and secondary performance through cognitive relaying and leveraging primary feedback

    KAUST Repository

    Hamza, Doha R.

    2014-06-01

    We consider a spectrum-sharing system, where the primary terminal operates in a time-slotted fashion and is active only when it has a packet to send. The secondary terminal uses spectrum sensing results and the primary automatic repeat request (ARQ) feedback to access the channel probabilistically. To enhance the primary\\'s system performance, the secondary user (SU) acts as a relay for the primary user (PU) in the event of transmission failure on the direct link of the latter. Closed-form expressions for the primary and secondary throughputs are obtained for the described scheme. The optimal medium access probabilities are then obtained by maximizing the secondary throughput subject to constraints that guarantee the stability of the considered queues, a minimum primary throughput, and a maximum primary queueing delay. The results clearly indicate the benefits of cognitive relaying in enhancing the throughput performance for both the PU and SU. Furthermore, by guaranteeing minimum rate and maximum delay requirements, our scheme is shown to provide a definitive notion of protection for the licensed users of the network. © 2013 IEEE.

  16. Using Primary Source Documents.

    Science.gov (United States)

    Mintz, Steven

    2003-01-01

    Explores the use of primary sources when teaching about U.S. slavery. Includes primary sources from the Gilder Lehrman Documents Collection (New York Historical Society) to teach about the role of slaves in the Revolutionary War, such as a proclamation from Lord Dunmore offering freedom to slaves who joined his army. (CMK)

  17. Medics in Primary School

    Science.gov (United States)

    Press, Colin

    2003-01-01

    Some time ago a flyer on "Medics in Primary School" came the author's way. It described a programme for making placements in primary schools available to medical students. The benefits of the program to medical students and participating schools were highlighted, including opportunities to develop communication skills and demystify…

  18. Tenth act amending the German atomic energy act

    International Nuclear Information System (INIS)

    Heller, W.

    2009-01-01

    On January 14, 2009, the German federal government introduced into parliament the 10th Act Amending the Atomic Energy Act. In the first reading in the federal parliament, Federal Minister for the Environment Gabriel emphasized 2 main points: Intensified protection of nuclear facilities and of transports of radioactive substances against unauthorized interventions; transfer by law to the Federal Office for Radiological Protection (BfS) of decommissioning of the Asse mine. Reliability review: The amendment to Sec.12 b of the Atomic Energy Act is to meet the different safety and security conditions after the terrorist attacks on September 11, 2001 in the United States and other terrorist activities afterwards (London, Madrid) also with respect to hazards arising to nuclear facilities and nuclear transports. The bill must be seen in conjunction with the Ordinance on Reliability Reviews under the Atomic Energy Act dated July 1, 1999 which covers reviews of reliability of persons holding special responsibilities. Asse II mine: The competence of the Federal Office for Radiological Protection is achieved by an amendment to Sec.23, Para.1, Number 2, Atomic Energy Act, in which the words ''and for the Asse II mine'' are added after the word ''waste.'' Further proceedings depend on the additional provision in a new Sec.57 b, Atomic Energy Act. Accordingly, the operation and decommissioning of the Asse II mine are subject to the regulations applicable to facilities of the federation pursuant to Sec.9a, Para.3. In this way, Asse II is given the same legal status as the federal waste management facilities. Moreover, it is stipulated that the mine is to be shut down immediately. (orig.)

  19. Reducing Prescriptions of Long-acting Benzodiazepine Drugs in Denmark

    DEFF Research Database (Denmark)

    Eriksen, Sophie Isabel; Bjerrum, Lars

    2015-01-01

    Prolonged consumption of benzodiazepine drugs (BZD) and benzodiazepine receptor agonists (zolpidem, zaleplon, zopiclone; altogether Z drugs) is related to potential physiological and psychological dependence along with other adverse effects. This study aimed to analyse the prescribing of long...... to the prescription. The observed reduction in BZD use was correlated to the introduction of new national guidelines on prescription of addictive drugs, but this study was not designed to detect a causal relationship. The prescribing of long-acting BZD decreased considerably more than the prescribing of short......-acting BZD (half-life >10 hr), compared to short-acting BZD in Denmark during a 10-year period. Descriptive analysis of total sales data from the Danish Register of Medicinal Product Statistics, to individuals in the primary healthcare sector, of all BZD and Z-drugs in the period of 2003-2013. Prescription...

  20. The social act of electronic medication prescribing.

    Science.gov (United States)

    Aarts, Jos

    2013-01-01

    Prescribing medication is embedded in social norms and cultures. In modern Western health care professionals and policy makers have attempted to rationalize medicine by addressing cost-effectiveness of diagnostic and therapeutic treatments and the development of guidelines and protocols based on the outcomes of clinical studies. These notions of cost-effectiveness and evidence-based medicine have also been embedded in technology such as electronic prescribing systems. Such constraining systems may clash with the reality of clinical practice, where formal boundaries of responsibility and authorization are often blurred. Such systems may therefore even impede patient care. Medication is seen as the essence of medical practice. Prescribing is a social act. In a hospital medications may be aimed at treating a patient for a specific condition, in primary care the professional often meets the patient with her or his social and cultural notions of a health problem. The author argues that the design and implementation of electronic prescribing systems should address the social and cultural context of prescribing. Especially in primary care, where health problems are often ill defined and evidence-based medicine guidelines do not always work as intended, studies need to take into account the sociotechnical character of electronic prescribing systems.

  1. 7 CFR 1210.302 - Act.

    Science.gov (United States)

    2010-01-01

    ... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE WATERMELON RESEARCH AND PROMOTION PLAN Watermelon Research and Promotion Plan Definitions § 1210.302 Act. Act means the Watermelon...

  2. Air traffic security act unconstitutional

    International Nuclear Information System (INIS)

    Heller, W.

    2006-01-01

    In the interest of more effective protective measures against terrorist attacks, the German federal parliament inter alia added a clause to the Air Traffic Security Act (Sec. 14, Para. 3, Air Traffic Security Act) empowering the armed forces to shoot down aircraft to be used as a weapon against human lives. In Germany, this defense possibility has been discussed also in connection with deliberate crashes of hijacked aircraft on nuclear power plants. The 1 st Division of the German Federal Constitutional Court, in its decision of February 15, 2006, ruled that Sec. 14, Para. 3, Air Traffic Security Act was incompatible with the Basic Law and thus was null and void (file No. 1 BvR 357/05) for two reasons: - There was no legislative authority on the part of the federal government. - The provision was incompatible with the basic right of life and the guarantee of human dignity as enshrined in the Basic Law. (orig.)

  3. The Problem of Agency; How Humans Act, How Machines Act

    DEFF Research Database (Denmark)

    Rose, Jeremy; Jones, M.; Truex, D.

    2003-01-01

    A long-standing debate in the IS literature concerns the relationship between technology and organization. Is it technology that acts on organizations, or humans that determine how technology is used? Proposals for a middle way between the extremes of technological and social determinism have bee...

  4. HASP: human acts simulation program

    International Nuclear Information System (INIS)

    Asai, Kiyoshi; Kambayashi, Shaw; Higuchi, Kenji; Kume, Etsuo; Otani, Takayuki; Fujii, Minoru; Uenaka, Junji; Fujisaki, Masahide.

    1990-01-01

    The Human Acts Simulation Program (HASP) aims computer simulations of mechanized human acts in a nuclear plant by a human shaped intelligent robot. The HASP has started as a ten-year program at Japan Atomic Energy Research Institute since 1987. The purposes of HASP are threefold as follows; development of basic and generalized design technologies for intelligent robots, development of basic technologies for an advanced intelligent and automatic nuclear power plant, and provision of artificial intelligence techniques for researchers in the nuclear field. In this paper, the contents of the HASP are described. (author)

  5. Enhanced primary and secondary performance through cognitive relaying and leveraging primary feedback

    KAUST Repository

    Hamza, Doha R.; Aï ssa, Sonia

    2014-01-01

    We consider a spectrum-sharing system, where the primary terminal operates in a time-slotted fashion and is active only when it has a packet to send. The secondary terminal uses spectrum sensing results and the primary automatic repeat request (ARQ) feedback to access the channel probabilistically. To enhance the primary's system performance, the secondary user (SU) acts as a relay for the primary user (PU) in the event of transmission failure on the direct link of the latter. Closed-form expressions for the primary and secondary throughputs are obtained for the described scheme. The optimal medium access probabilities are then obtained by maximizing the secondary throughput subject to constraints that guarantee the stability of the considered queues, a minimum primary throughput, and a maximum primary queueing delay. The results clearly indicate the benefits of cognitive relaying in enhancing the throughput performance for both the PU and SU. Furthermore, by guaranteeing minimum rate and maximum delay requirements, our scheme is shown to provide a definitive notion of protection for the licensed users of the network. © 2013 IEEE.

  6. Primary Sclerosing Cholangitis (PSC)

    Science.gov (United States)

    ... Legacy Society Make Gifts of Stock Donate Your Car Personal Fundraising Partnership & Support Share Your Story Spread the Word Give While You Shop Contact Us Donate Now Primary Sclerosing Cholangitis Back ...

  7. Primary cultures of astrocytes

    DEFF Research Database (Denmark)

    Lange, Sofie C; Bak, Lasse Kristoffer; Waagepetersen, Helle S

    2012-01-01

    During the past few decades of astrocyte research it has become increasingly clear that astrocytes have taken a central position in all central nervous system activities. Much of our new understanding of astrocytes has been derived from studies conducted with primary cultures of astrocytes...... subsequently found in vivo. Nevertheless, primary cultures of astrocytes are an in vitro model that does not fully mimic the complex events occurring in vivo. Here we present an overview of the numerous contributions generated by the use of primary astrocyte cultures to uncover the diverse functions...... of astrocytes. Many of these discoveries would not have been possible to achieve without the use of astrocyte cultures. Additionally, we address and discuss the concerns that have been raised regarding the use of primary cultures of astrocytes as an experimental model system....

  8. Primary Meningeal Rhabdomyosarcoma

    Science.gov (United States)

    Palta, Manisha; Riedel, Richard F.; Vredenburgh, James J.; Cummings, Thomas J.; Green, Scott; Chang, Zheng; Kirkpatrick, John P.

    2011-01-01

    Primary meningeal rhabdomyosarcoma is a rare primary brain malignancy, with scant case reports. While most reports of primary intracranial rhabdomyosarcoma occur in pediatric patients, a handful of cases in adult patients have been reported in the medical literature. We report the case of a 44-year-old male who developed primary meningeal rhabdomyosarcoma. After developing episodes of right lower extremity weakness, word finding difficulty, and headaches, a brain magnetic resonance imaging (MRI) demonstrated a vertex lesion with radiographic appearance of a meningeal-derived tumor. Subtotal surgical resection was performed due to sagittal sinus invasion and initial pathology was interpreted as an anaplastic meningioma. Re-review of pathology demonstrated rhabdomyosarcoma negative for alveolar translocation t(2;13). Staging studies revealed no evidence of disseminated disease. He was treated with stereotactic radiotherapy with concurrent temozolamide to be followed by vincristine, actinomycin-D, and cyclophosphamide (VAC) systemic therapy. PMID:21772793

  9. Primary Meningeal Rhabdomyosarcoma

    Directory of Open Access Journals (Sweden)

    Manisha Palta

    2011-01-01

    Full Text Available Primary meningeal rhabdomyosarcoma is a rare primary brain malignancy, with scant case reports. While most reports of primary intracranial rhabdomyosarcoma occur in pediatric patients, a handful of cases in adult patients have been reported in the medical literature. We report the case of a 44-year-old male who developed primary meningeal rhabdomyosarcoma. After developing episodes of right lower extremity weakness, word finding difficulty, and headaches, a brain magnetic resonance imaging (MRI demonstrated a vertex lesion with radiographic appearance of a meningeal-derived tumor. Subtotal surgical resection was performed due to sagittal sinus invasion and initial pathology was interpreted as an anaplastic meningioma. Re-review of pathology demonstrated rhabdomyosarcoma negative for alveolar translocation t(2;13. Staging studies revealed no evidence of disseminated disease. He was treated with stereotactic radiotherapy with concurrent temozolamide to be followed by vincristine, actinomycin-D, and cyclophosphamide (VAC systemic therapy.

  10. Primary meningeal rhabdomyosarcoma.

    Science.gov (United States)

    Palta, Manisha; Riedel, Richard F; Vredenburgh, James J; Cummings, Thomas J; Green, Scott; Chang, Zheng; Kirkpatrick, John P

    2011-01-01

    Primary meningeal rhabdomyosarcoma is a rare primary brain malignancy, with scant case reports. While most reports of primary intracranial rhabdomyosarcoma occur in pediatric patients, a handful of cases in adult patients have been reported in the medical literature. We report the case of a 44-year-old male who developed primary meningeal rhabdomyosarcoma. After developing episodes of right lower extremity weakness, word finding difficulty, and headaches, a brain magnetic resonance imaging (MRI) demonstrated a vertex lesion with radiographic appearance of a meningeal-derived tumor. Subtotal surgical resection was performed due to sagittal sinus invasion and initial pathology was interpreted as an anaplastic meningioma. Re-review of pathology demonstrated rhabdomyosarcoma negative for alveolar translocation t(2;13). Staging studies revealed no evidence of disseminated disease. He was treated with stereotactic radiotherapy with concurrent temozolamide to be followed by vincristine, actinomycin-D, and cyclophosphamide (VAC) systemic therapy.

  11. Primary Nurse - Role Evolution

    Science.gov (United States)

    Mundinger, Mary O'Neil

    1973-01-01

    Primary nursing means that each patient has an individual nurse who is responsible for assessing his nursing needs and planning and evaluating his nursing care. The article describes the advantages and problems connected with this approach to patient care. (AG)

  12. Multiple Primary Tumors

    African Journals Online (AJOL)

    2017-12-05

    Dec 5, 2017 ... Multiple primary tumors occur in clinical practice causing diagnostic dilemma. It is not very .... was estrogen receptor negative, progesterone receptor negative, and ... cervical, ovarian, and urinary bladder cancers. Multiple.

  13. Primary infertility (image)

    Science.gov (United States)

    Primary infertility is a term used to describe a couple that has never been able to conceive a pregnancy ... to do so through unprotected intercourse. Causes of infertility include a wide range of physical as well ...

  14. Primary Intraorbital Ectopic Meningioma

    Science.gov (United States)

    Yokoyama, Tetsuo; Nishizawa, Shigeru; Sugiyama, Kenji; Yokota, Noki; Ohta, Seiji; Uemura, Kenichi; Hinokuma, Kaoru; Inenaga, Chikanori

    1999-01-01

    We report a case of intraorbital meningioma. Operative findings and histopathological examination revealed the tumoc to be meningothelial meningloma and to be located entirely outside the optic dura. This case demonstrates the occurrence of primary intraorbital ectopic meningioma, and the tumor was removed through a modified Dolenc approach. The primary intraorbital ectopic meningioma is discussed and the surgical approach to the orbital apex region is reviewed. ImagesFigure 1Figure 2Figure 4Figure 5 PMID:17171081

  15. Primary leiomyosarcoma of epididymis

    Directory of Open Access Journals (Sweden)

    Dillip Kumar Muduly

    2012-01-01

    Full Text Available Primary leiomyosarcomas rarely arise from epididymis. But they are the most common histopathological types of sarcoma arising from the epididymis. Primary epididymal leiomyosarcoma occurs usually in older patients. We report a young patient of 35 years presenting with leiomyosarcoma of left epididymis. He did not have any metastasis and underwent left high inguinal orchiectomy. He is on regular follow-up and disease free for last two years.

  16. Primary care ... where?

    Science.gov (United States)

    Adcock, G B

    1999-07-01

    Corporate-based nurse managed centers are not the national norm. More prevalent is the use of an occupational health or physician-directed medical model of care. The author describes how a 14-year-old primary care center at a North Carolina computer software company is just "business as usual" when viewed in the context of the company's philosophy, goals, and culture. Included are considerations for nurse practitioners interested in the successful transplantation of this primary care model to other settings.

  17. Sport supporting act: terminology issues

    Directory of Open Access Journals (Sweden)

    Petr Vlček

    2013-01-01

    Full Text Available BACKGROUND: The text deals with terminology issues from an interdisciplinary point of view. It is based on two different disciplines, law and kinanthropology, in an area of their overlap. AIM: The aim of the author is to point out some possible legislative problems, which could arise due to the current reading of the sport supporting act (Act no. 115/2001. The second aim of the author is to contribute to the discussion of kinantropologists (possibly also the educational researchers and lawyers and to stress the importance of the systematic approach to terminology formulation. METHODS: The author uses the method of language interpretation. We also use the basic analytical methods, induction and deduction, while we stress the systematic approach to the term formulation. RESULTS: The analysis of the sport supporting act terminology shows some specific legislative problems, which could arise due to the definition of sport in the sport supporting act. The author discusses a possible alternative solution. CONCLUSION: According to the opinion of the author, clear, obvious and unified terminology of kinantropologists as specialists in their discipline should represent a source, from which other sciences could derive their terminology. Defined and inexpert terminology used in other disciplines should not be used as an argument for its adopting in kinanthropology.

  18. Against acts of nuclear terrorism

    International Nuclear Information System (INIS)

    Heller, W.

    2007-01-01

    The Act on the International Convention of the United Nations of April 13, 2005 on Combating Acts of Nuclear Terrorism was promulgated in the German Federal Gazette and entered into force one day later. The Convention expresses the deep concern about the worldwide escalation of all kinds and manifestations of acts of terrorism. What was true in April 2005 (the year the UN convention was adopted) is even more true today. At the same time, however, the Convention recognizes the right of all nations to develop and use nuclear power for peaceful purposes, acknowledging their justified interest in the possible benefits of the peaceful uses of nuclear power. As the Convention was signed in German still during the term of office of the Red-Green government, this passage is a remarkable acceptance of the realities of the world and past peaceful uses of nuclear power in Germany. Whether or not the convention will become an effective instrument to be used against acts of nuclear terrorism and threats depends on its entering into force after deposition of 22 ratification documents, and on as many states as possible acceding to it. Irrespective of these aspects, action in the spirit of the Convention should be taken now, criminal law should be adapted, and international cooperation should be improved and strengthened. (orig.)

  19. The American Inventors Protection Act

    NARCIS (Netherlands)

    Hoffmann, Arvid O.I.; Kleimeier, Stefanie; Mimiroglu, Nagihan; Pennings, Joost M.E.

    2018-01-01

    We examine the impact of innovation disclosure through patenting on firms' cost of debt, focusing on the American Inventors Protection Act (AIPA) as an exogenous shock in innovation disclosure regulation. Post-AIPA, firms have an incentive to apply for patents only if commercial success is likely.

  20. Paraconsistent semantics of speech acts

    NARCIS (Netherlands)

    Dunin-Kȩplicz, Barbara; Strachocka, Alina; Szałas, Andrzej; Verbrugge, Rineke

    2015-01-01

    This paper discusses an implementation of four speech acts: assert, concede, request and challenge in a paraconsistent framework. A natural four-valued model of interaction yields multiple new cognitive situations. They are analyzed in the context of communicative relations, which partially replace

  1. Nuclear Activities (Prohibitions) Act 1983

    International Nuclear Information System (INIS)

    1983-01-01

    The purpose of this Act is to protect the health and safety of the people of Victoria and its environment by prohibiting nuclear activities from being carried out and regulating the possession of certain nuclear material in a manner consistent with assisting Australia in meeting its international nuclear non-proliferation objectives. (NEA) [fr

  2. Dumping at Sea Act 1974

    International Nuclear Information System (INIS)

    1974-01-01

    This Act enables the United Kingdom Government to ratify both the Oslo Convention of 1972 for the Prevention of Marine Pollution by Dumping from Ships and Aircraft and the London Convention of 1972 on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter. (NEA) [fr

  3. Affordable Care Act and Women

    Science.gov (United States)

    ... quality care for older women, and ends the gender discrimination that requires women to pay more for the same insurance coverage ... the Affordable Care Act and 13 million more women will gain coverage by 2016. Maternity Coverage Preventive ... Expanded Insurance Coverage Endnotes Download "rb. ...

  4. Progress in implementing the Federal Facility Compliance Act

    International Nuclear Information System (INIS)

    Bubar, P.; Stone, M.E.

    1994-01-01

    Hazardous waste and hazardous components of mixed waste require treatment prior to disposal, in accordance with the Resource Conservation and Recovery Act as amended by the Federal Facility Compliance Act. The primary driver for the United States Department of Energy's mixed waste management strategy is the Federal Facility Compliance Act. This Act requires each site generating or storing mixed waste to prepare a treatment plan addressing all mixed waste at the site, with a schedule for treatment capacity construction, and milestones for treating waste when known treatment technologies exist. As of this writing, the Department has published conceptual site treatment plans identifying the technical on-site options and options at other Department or commercial sites. It is now finalizing the Mixed Waste Inventory and Technology Report required by the Act, providing additional detail on its waste streams and treatment capabilities. Now the Department, at its sites, is in the difficult process of winnowing down treatment options in conjunction with the States, with input from the public and other interested parties. Many technical questions, policy and funding issues, and equity concerns among the States must be addressed to enable the Department to propose its preferred treatment options by August 1994

  5. Long-acting reversible contraceptive acceptability and unintended pregnancy among women presenting for short-acting methods: a randomized patient preference trial.

    Science.gov (United States)

    Hubacher, David; Spector, Hannah; Monteith, Charles; Chen, Pai-Lien; Hart, Catherine

    2017-02-01

    Measures of contraceptive effectiveness combine technology and user-related factors. Observational studies show higher effectiveness of long-acting reversible contraception compared with short-acting reversible contraception. Women who choose long-acting reversible contraception may differ in key ways from women who choose short-acting reversible contraception, and it may be these differences that are responsible for the high effectiveness of long-acting reversible contraception. Wider use of long-acting reversible contraception is recommended, but scientific evidence of acceptability and successful use is lacking in a population that typically opts for short-acting methods. The objective of the study was to reduce bias in measuring contraceptive effectiveness and better isolate the independent role that long-acting reversible contraception has in preventing unintended pregnancy relative to short-acting reversible contraception. We conducted a partially randomized patient preference trial and recruited women aged 18-29 years who were seeking a short-acting method (pills or injectable). Participants who agreed to randomization were assigned to 1 of 2 categories: long-acting reversible contraception or short-acting reversible contraception. Women who declined randomization but agreed to follow-up in the observational cohort chose their preferred method. Under randomization, participants chose a specific method in the category and received it for free, whereas participants in the preference cohort paid for the contraception in their usual fashion. Participants were followed up prospectively to measure primary outcomes of method continuation and unintended pregnancy at 12 months. Kaplan-Meier techniques were used to estimate method continuation probabilities. Intent-to-treat principles were applied after method initiation for comparing incidence of unintended pregnancy. We also measured acceptability in terms of level of happiness with the products. Of the 916

  6. 22 CFR 901.10 - Act.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Act. 901.10 Section 901.10 Foreign Relations FOREIGN SERVICE GRIEVANCE BOARD GENERAL Meanings of Terms As Used in This Chapter § 901.10 Act. Act means the Foreign Service Act of 1980 (Pub. L. 96-465, October 17, 1980), as amended. [56 FR 55458, Oct. 28...

  7. 7 CFR 1280.101 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1280.101 Section 1280.101 Agriculture... INFORMATION ORDER Lamb Promotion, Research, and Information Order Definitions § 1280.101 Act. Act means the Commodity Promotion, Research, and Information Act of 1996 (7 U.S.C. 7411-7425; Pub. L. 104-127; 110 Stat...

  8. 7 CFR 1150.101 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Act. 1150.101 Section 1150.101 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and... Definitions § 1150.101 Act. Act means Title I, Subtitle B, of the Dairy and Tobacco Adjustment Act of 1983...

  9. 12 CFR 541.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Act. 541.2 Section 541.2 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY DEFINITIONS FOR REGULATIONS AFFECTING FEDERAL SAVINGS ASSOCIATIONS § 541.2 Act. The term Act means the Home Owners' Loan Act of 1933, as amended. ...

  10. 7 CFR 1250.302 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1250.302 Section 1250.302 Agriculture... Research and Promotion Order Definitions § 1250.302 Act. Act means the Egg Research and Consumer Information Act and as it may be amended (Pub. L. 93-428). ...

  11. 7 CFR 1207.302 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1207.302 Section 1207.302 Agriculture... Potato Research and Promotion Plan Definitions § 1207.302 Act. Act means the Potato Research and Promotion Act, Title III of Public Law 91-670, 91st Congress, approved January 11, 1971, 84 Stat. 2041, as...

  12. 7 CFR 985.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 985.2 Section 985.2 Agriculture Regulations of... SPEARMINT OIL PRODUCED IN THE FAR WEST Order Regulating Handling Definitions § 985.2 Act. Act means Public Act No. 10, 73d Congress, as amended, and reenacted and amended by the Agricultural Marketing...

  13. 7 CFR 1230.601 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1230.601 Section 1230.601 Agriculture... CONSUMER INFORMATION Procedures for the Conduct of Referendum Definitions § 1230.601 Act. The term Act means the Pork Promotion, Research, and Consumer Information Act of 1985 (7 U.S.C. 4801-4819) and any...

  14. 29 CFR 401.17 - Act.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 2 2010-07-01 2010-07-01 false Act. 401.17 Section 401.17 Labor Regulations Relating to Labor OFFICE OF LABOR-MANAGEMENT STANDARDS, DEPARTMENT OF LABOR LABOR-MANAGEMENT STANDARDS MEANING OF TERMS USED IN THIS SUBCHAPTER § 401.17 Act. Act means the Labor-Management Reporting and Disclosure Act...

  15. 7 CFR 1218.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1218.1 Section 1218.1 Agriculture Regulations of... INFORMATION ORDER Blueberry Promotion, Research, and Information Order Definitions § 1218.1 Act. Act means the Commodity Promotion, Research, and Information Act of 1996 (7 U.S.C. 7401-7425; Pub. L. 104-127; 110 Stat...

  16. 7 CFR 1216.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1216.1 Section 1216.1 Agriculture Regulations of... ORDER Peanut Promotion, Research, and Information Order Definitions § 1216.1 Act. Act means the Commodity Promotion, Research, and Information Act of 1996 (7 U.S.C. 7401-7425; Public Law 104-127, 110 Stat...

  17. 7 CFR 924.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 924.2 Section 924.2 Agriculture Regulations of... WASHINGTON AND IN UMATILLA COUNTY, OREGON Order Regulating Handling Definitions § 924.2 Act. Act means Public Act No. 10, 73d Congress (May 12, 1933), as amended and as re-enacted and amended by the Agricultural...

  18. 34 CFR 300.4 - Act.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Act. 300.4 Section 300.4 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES... Definitions Used in This Part § 300.4 Act. Act means the Individuals with Disabilities Education Act, as...

  19. 7 CFR 1206.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1206.1 Section 1206.1 Agriculture Regulations of... Mango Promotion, Research, and Information Order Definitions § 1206.1 Act. Act means the Commodity Promotion, Research, and Information Act of 1996 (7 U.S.C. 7411-7425; Public Law 104-127; 110 Stat. 1029...

  20. 7 CFR 1220.600 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1220.600 Section 1220.600 Agriculture... CONSUMER INFORMATION Procedures To Request a Referendum Definitions § 1220.600 Act. Act means the Soybean, Promotion, Research, and Consumer Information Act set forth in title XIX, subtitle E, of the Food...

  1. 7 CFR 1205.302 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1205.302 Section 1205.302 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Research and Promotion Order Definitions § 1205.302 Act. Act means the Cotton Research and Promotion Act...

  2. 7 CFR 1212.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1212.1 Section 1212.1 Agriculture Regulations of..., Consumer Education, and Industry Information Order Definitions § 1212.1 Act. “Act” means the Commodity Promotion, Research, and Information Act of 1996, (7 U.S.C. 7411-7425), and any amendments to that Act. ...

  3. 7 CFR 1221.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1221.1 Section 1221.1 Agriculture Regulations of... INFORMATION ORDER Sorghum Promotion, Research, and Information Order Definitions § 1221.1 Act. Act means the Commodity Promotion, Research, and Information Act of 1996 (7 U.S.C. 7411-7425), and any amendments thereto. ...

  4. 7 CFR 1219.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1219.1 Section 1219.1 Agriculture Regulations of... INFORMATION Hass Avocado Promotion, Research, and Information Order Definitions § 1219.1 Act. Act means the Hass Avocado Promotion, Research, and Information Act of 2000, Public Law 106-387, 7 U.S.C. 7801-7813...

  5. 7 CFR 1220.101 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1220.101 Section 1220.101 Agriculture... CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.101 Act. The term Act means the Soybean Promotion, Research, and Consumer Information Act, subtitle E of title XIX, of the Food...

  6. 7 CFR 958.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 958.2 Section 958.2 Agriculture Regulations of... IN IDAHO, AND MALHEUR COUNTY, OREGON Order Regulating Handling Definitions § 958.2 Act. Act means Public Act No. 10, 73d Congress, as amended and as reenacted and amended by the Agricultural Marketing...

  7. 34 CFR 303.6 - Act.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Act. 303.6 Section 303.6 Education Regulations of the..., Eligibility, and Other General Provisions § 303.6 Act. As used in this part, Act means the Individuals with Disabilities Education Act. (Authority: 20 U.S.C. 1400) ...

  8. 7 CFR 945.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 945.2 Section 945.2 Agriculture Regulations of... COUNTIES IN IDAHO, AND MALHEUR COUNTY, OREGON Order Regulating Handling Definitions § 945.2 Act. Act means Public Act No. 10, 73d Congress, as amended and as reenacted and amended by the Agricultural Marketing...

  9. 78 FR 4462 - Sunshine Act; Meeting Notice

    Science.gov (United States)

    2013-01-22

    ... goals for 2013 5. Panel presentation and discussion on Succession Planning and Leadership Development... comment 7. Consider and act on other business 8. Consider and act on motion to adjourn the meeting... comment 8. Consider and act on other business 9. Consider and act on adjournment of meeting Institutional...

  10. 40 CFR 1508.2 - Act.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Act. 1508.2 Section 1508.2 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.2 Act. Act means the National Environmental Policy Act, as amended (42 U.S.C. 4321, et seq.) which is also referred to as “NEPA.” ...

  11. Other primary headaches

    Directory of Open Access Journals (Sweden)

    Anish Bahra

    2012-01-01

    Full Text Available The ′Other Primary Headaches′ include eight recognised benign headache disorders. Primary stabbing headache is a generally benign disorder which often co-exists with other primary headache disorders such as migraine and cluster headache. Primary cough headache is headache precipitated by valsalva; secondary cough has been reported particularly in association with posterior fossa pathology. Primary exertional headache can occur with sudden or gradual onset during, or immediately after, exercise. Similarly headache associated with sexual activity can occur with gradual evolution or sudden onset. Secondary headache is more likely with both exertional and sexual headache of sudden onset. Sudden onset headache, with maximum intensity reached within a minute, is termed thunderclap headache. A benign form of thunderclap headache exists. However, isolated primary and secondary thunderclap headache cannot be clinically differentiated. Therefore all headache of thunderclap onset should be investigated. The primary forms of the aforementioned paroxysmal headaches appear to be Indomethacin sensitive disorders. Hypnic headache is a rare disorder which is termed ′alarm clock headache′, exclusively waking patients from sleep. The disorder can be Indomethacin responsive, but can also respond to Lithium and caffeine. New daily persistent headache is a rare and often intractable headache which starts one day and persists daily thereafter for at least 3 months. The clinical syndrome more often has migrainous features or is otherwise has a chronic tension-type headache phenotype. Management is that of the clinical syndrome. Hemicrania continua straddles the disorders of migraine and the trigeminal autonomic cephalalgias and is not dealt with in this review.

  12. Draft of a Fourth Act amending the Atomic Energy Act

    International Nuclear Information System (INIS)

    1976-01-01

    The bill comprises regulations concerning 1. the handling over and treatment of radioactive waste as well as its final storage under federal adminstration (article 87, section 3, sentence 1 Basic Law), 2. authorizations regarding the issuing of statuatory orders supplementing and extending sections 11 and 12 of the Atomic Energy Act, particulary in aim of the rationalization of licensing and the carrying-out of governmental supervision, 3. supplementing penal provisions. (LN) [de

  13. Resin transfer molding for advanced composite primary aircraft structures

    Science.gov (United States)

    Markus, Alan; Palmer, Ray

    1991-01-01

    Resin Transfer Molding (RTM) has been identified by Douglas Aircraft Company (DAC) and industry to be one of the promising processes being developed today which can break the cost barrier of implementing composite primary structures into a commercial aircraft production environment. The RTM process developments and scale-up plans Douglas Aircrart will be conducting under the NASA ACT contract are discussed.

  14. 7 CFR 905.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 905.2 Section 905.2 Agriculture Regulations of... TANGELOS GROWN IN FLORIDA Order Regulating Handling Definitions § 905.2 Act. Act means Public Act No. 10... Agreement Act of 1937, as amended. (48 Stat. 31, as amended; 7 U.S.C. 601 et seq.; 68 Stat. 906, 1047.) ...

  15. 7 CFR 955.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 955.2 Section 955.2 Agriculture Regulations of... § 955.2 Act. Act means Public Act No. 10, 73d Congress (May 12, 1933), as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (Sec. 1-19, 48 Stat. 31, as...

  16. 7 CFR 920.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 920.2 Section 920.2 Agriculture Regulations of... § 920.2 Act. Act means Public Act No. 10, 73d Congress (May 12, 1933), as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (48 Stat. 31, as amended; 7 U.S.C...

  17. 7 CFR 929.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 929.2 Section 929.2 Agriculture Regulations of... ISLAND IN THE STATE OF NEW YORK Order Regulating Handling Definitions § 929.2 Act. Act means Public Act... Marketing Agreement Act of 1937, as amended (secs. 1-19, 48 Stat. 31, as amended; 7 U.S.C. 601-674). ...

  18. 7 CFR 947.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 947.2 Section 947.2 Agriculture Regulations of... Definitions § 947.2 Act. Act means Public Act No. 10, 73d Congress, as amended and as reenacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (48 Stat. 31, as amended; 7 U.S.C. 601 et...

  19. 29 CFR 4.103 - The Act.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 1 2010-07-01 2010-07-01 true The Act. 4.103 Section 4.103 Labor Office of the Secretary... Contract Act Introductory § 4.103 The Act. The McNamara-O'Hara Service Contract Act of 1965 (Pub. L. 89-286, 79 Stat. 1034, 41 U.S.C. 351 et seq.), hereinafter referred to as the Act, was approved by the...

  20. 7 CFR 953.2 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Act. 953.2 Section 953.2 Agriculture Regulations of... Order Regulating Handling Definitions § 953.2 Act. Act means Public Act No. 10, 73d Congress, as amended and as re-enacted and amended by the Agricultural Marketing Agreement Act of 1937, as amended (7 U.S.C...

  1. 7 CFR 1160.101 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Act. 1160.101 Section 1160.101 Agriculture Regulations... Definitions § 1160.101 Act. Act means the Fluid Milk Promotion Act of 1990, Subtitle H of Title XIX of the Food, Agriculture, Conservation, and Trade Act of 1990, Public Law 101-624, 7 U.S.C. 6401-6417, and any...

  2. Primary Ectopic Ethmoidal Craniopharyngioma.

    Science.gov (United States)

    Preti, Andrea; Karligkiotis, Apostolos; Facco, Carla; Ottini, Giorgia; Volpi, Luca; Castelnuovo, Paolo

    2017-06-01

    Craniopharyngiomas are benign but aggressive epithelial tumors usually originating in the anterior lobe of the pituitary gland from squamous remnants of an incompletely involuted craniopharingeal duct developing from the Rathke pouch. To the authors' knowledge only 1 patient of a primary isolated ethmoidal craniopharyngioma has been reported in the literature.The authors report the case of a 17-year-old boy with a primary extracranial ethmoidal craniopharyngioma. An endoscopic endonasal approach was employed to resect the tumor. After 2 years of clinical and radiological follow-up no recurrence of disease was observed.Primary ethmoidal craniopharyngiomas are rare entities and biopsy is necessary for diagnosis. However, a preoperative assessment by means of nasal endoscopy, computed tomography scan, and enhanced magnetic resonance imaging is mandatory to better evaluate the extension and characteristics of the tumor. The endoscopic endonasal technique is a safe and effective approach for the treatment of these lesions.

  3. Primary renal synovial sarcoma

    Directory of Open Access Journals (Sweden)

    Girish D. Bakhshi

    2012-03-01

    Full Text Available Primary Renal Sarcoma is rare tumor comprising only 1% of all renal tumours. Synovial sarcomas are generally deep-seated tumors arising in the proximity of large joints of adolescents and young adults and account for 5-10% of all soft tissue tumours. Primary synovial sarcoma of kidney is rare and has poor prognosis. It can only be diagnosed by immunohistochemistry. It should be considered as a differential in sarcomatoid and spindle cell tumours. We present a case of 33-year-old female, who underwent left sided radical nephrectomy for renal tumour. Histopathology and genetic analysis diagnosed it to be primary renal synovial sarcoma. Patient underwent radiation therapy and 2 years follow up is uneventful. A brief case report with review of literature is presented.

  4. Primary headaches in children

    Directory of Open Access Journals (Sweden)

    Ajay Kumar Pan

    2015-01-01

    Full Text Available Headache is a widespread clinical problem; the prevalence is high in all age groups, from which children and teenagers are not spared. It has been reported that, as many as 75% of school-age children may experience headache infrequently, among them 10% have recurrent headaches. [1],[2] The vast majority of headaches are primary and classified as migraine, tension-type headache (TTH, cluster headache, and other trigeminal autonomic cephalgias. The type of primary headaches could usually be diagnosed by a thorough and careful history taking, and physical examination. Once the diagnosis of migraine is established and appropriate reassurance provided, a balanced and individually tailored treatment plan can be instituted. The goal of treatment includes abortive or acute pain treatment, preventive long-term treatment, and biobehavioral therapy. Knowledge of precise impact of primary headaches on child′s quality of life helps to design a proper comprehensive treatment plan.

  5. Normocalcemic primary hyperparathyroidism

    Science.gov (United States)

    Bilezikian, John P.; Silverberg, Shonni J.

    2011-01-01

    SUMMARY Primary hyperparathyroidism is a common disorder of mineral metabolism characterized by incompletely regulated, excessive secretion of parathyroid hormone from one or more of the parathyroid glands. The historical view of this disease describes two distinct entities marked by two eras. When primary hyperparathyroidism was first discovered about 80 years ago, it was always symptomatic with kidney stones, bone disease and marked hypercalcemia. With the advent of the multichannel autoanalyzer about 40 years ago, the clinical phenotype changed to a disorder characterized by mild hypercalcemia and the absence of classical other features of the disease. We may now be entering a 3rd era in the history of this disease in which patients are being discovered with normal total and ionized serum calcium concentrations but with parathyroid hormone levels that are consistently elevated. In this article, we describe this new entity, normocalcemic primary hyperparathyroidism, a forme fruste of the disease. PMID:20485897

  6. [Primary care in Ireland].

    Science.gov (United States)

    Sánchez-Sagrado, T

    Spanish doctors are still leaving the country to look for quality work. Ireland is not a country with many Spanish professionals but it is interesting to know its particular Health care system. Ireland is one of the countries with a national health care system, although it has a mixture of private health care insurance schemes. People have a right to health care if they have been living in Ireland at least for a year. Access to the primary care health system depends on age and income: free of charge for Category 1 and co-payments for the rest. This division generates great inequalities among the population. Primary Care doctors are self-employed, and they work independently. However, since 2001 they have tended to work in multidisciplinary teams in order to strengthen the Primary Care practice. Salary is gained from a combination of public and private incomes which are not differentiated. The role of the General Practitioner consists in the treatment of acute and chronic diseases, minor surgery, child care, etc. There is no coordination between Primary and Secondary care. Access to specialised medicine is regulated by the price of consultation. Primary Care doctors are not gatekeepers. To be able to work here, doctors must have three years of training after medical school. After that, Continuing Medical Education is compulsory, and the college of general practitioners monitors it annually. The Irish health care system does not fit into the European model. Lack of a clear separation between public and private health care generates great inequalities. The non-existence of coordination between primary and specialised care leads to inefficiencies, which Ireland cannot allow itself after a decade of economic crisis. Copyright © 2017 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

  7. Thoughts on primary care.

    Science.gov (United States)

    Raskin, Lynne

    2010-01-01

    The uptake of family health teams in Ontario has been tremendous. And the creation of group practices in primary care has taken root in other provinces as well. For many people, being involved with something new is exciting. At the same time, once they are committed, they discover the challenges that can be simultaneously exhilarating and frustrating. This issue of Healthcare Quarterly offers two articles that provide interesting reflections on what has been learned so far from the perspectives of both team leadership and the team members themselves within a transforming primary care system.

  8. False memories for aggressive acts.

    Science.gov (United States)

    Laney, Cara; Takarangi, Melanie K T

    2013-06-01

    Can people develop false memories for committing aggressive acts? How does this process compare to developing false memories for victimhood? In the current research we used a simple false feedback procedure to implant false memories for committing aggressive acts (causing a black eye or spreading malicious gossip) or for victimhood (receiving a black eye). We then compared these false memories to other subjects' true memories for equivalent events. False aggressive memories were all too easy to implant, particularly in the minds of individuals with a proclivity towards aggression. Once implanted, the false memories were indistinguishable from true memories for the same events, on several dimensions, including emotional content. Implications for aggression-related memory more generally as well as false confessions are discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Act No 282 reorganising ENEA

    International Nuclear Information System (INIS)

    1991-01-01

    This Act reorganises the National Agency for Research and Development of Nuclear and Alternative Energies - ENEA - and reorients its responsibilities. It is now called the National Agency for New Technologies, Energy and the Environment and retains its acronym (Ente per le nouve tecnologies, l'energia e l'ambiente - ENEA). It will also deal with environmental questions and new technologies, in particular, carrying out studies and research on the latter and evaluating their economic, social and environmental consequences. Already in 1982, the National Nuclear Energy Committee (CNEN) had been entrusted with wider tasks and renamed ENEA. The present ENEA retains its competence regarding nuclear activities, notably in the field of nuclear safety and radiation protection. The new Act confirms the tasks already conferred on the Nuclear Safety and Health Protection Directorate (DISP), we well as its operational independence while remaining within ENEA [fr

  10. Primary lymphoma of the brain

    Science.gov (United States)

    Brain lymphoma; Cerebral lymphoma; Primary lymphoma of the central nervous system; Lymphoma - brain ... The cause of primary brain lymphoma is not known. People with a weakened immune system are at high risk for primary lymphoma of the brain. ...

  11. Clean Air Act. Revision 5

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-15

    This Reference Book contains a current copy of the Clean Air Act, as amended, and those regulations that implement the statute and appear to be most relevant to DOE activities. The document is provided to DOE and contractor staff for informational purposes only and should not be interpreted as legal guidance. This Reference Book has been completely revised and is current through February 15, 1994.

  12. 78 FR 29659 - Forfeiture Procedures Under the Endangered Species Act and the Lacey Act Amendments

    Science.gov (United States)

    2013-05-21

    .... APHIS-2007-0086] RIN 0579-AD50 Forfeiture Procedures Under the Endangered Species Act and the Lacey Act... Endangered Species Act of 1973, as amended (ESA), and the Lacey Act Amendments of 1981, as amended, that... INFORMATION: Background The Endangered Species Act (ESA) of 1973, as amended (16 U.S.C. 1531 et seq.), was...

  13. 76 FR 64115 - Privacy Act of 1974; Privacy Act System of Records

    Science.gov (United States)

    2011-10-17

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (11-092)] Privacy Act of 1974; Privacy Act... retirement of one Privacy Act system of records notice. SUMMARY: In accordance with the Privacy Act of 1974, NASA is giving notice that it proposes to cancel the following Privacy Act system of records notice...

  14. Making the Most of the Every Student Succeeds Act (ESSA): Helping States Focus on School Equity, Quality and Climate

    Science.gov (United States)

    Penuel, William; Meyer, Elizabeth; Valladares, Michelle Renée

    2016-01-01

    Staff in State Departments of Education are diligently reviewing and revising their state accountability systems to meet the new requirements and opportunities of the Every Student Succeeds Act (ESSA). ESSA is the latest reauthorization of the 1965 Elementary and Secondary Education Act, the primary federal bill guiding K-12 education policy. As a…

  15. Surgery of Primary Melanomas

    Directory of Open Access Journals (Sweden)

    Piotr Rutkowski

    2010-05-01

    Full Text Available Surgery remains the mainstay of melanoma therapy, regardless of the tumor site. Only the early diagnosis combined with proper surgical therapy currently gives patients affected by this malignancy the chance for a full cure. The main goal of surgical therapy is to provide the local control of the disease and to secure long-term survival of the patient without reasonable functional and esthetic impairment. The recommended method of biopsy—excisional biopsy, as an initial diagnostic and, to some extent, therapeutic procedure—is performed under local anesthesia as an elliptical incision with visual clear margins of 1–3 mm and with some mm of subcutaneous tissue. The extent of radical excision of the primary tumor (or scar after excisional biopsy is based on the histopathologic characteristics of the primary tumor and usually consists of 1–2 cm margins with primary closure. The philosophy behind conducted randomized clinical trials has been to find the most conservative surgical approach that is able to guarantee the same results as more demolitive treatment. This has been the background of the trials designed to define the correct margins of excision around a primary cutaneous melanoma. Much less definition can be dedicated to the surgical management of patients with non-cutaneous melanomas.

  16. Surgery of Primary Melanomas

    Energy Technology Data Exchange (ETDEWEB)

    Rutkowski, Piotr, E-mail: rutkowskip@coi.waw.pl; Zdzienicki, Marcin; Nowecki, Zbigniew I. [Soft Tissue/Bone Sarcoma and Melanoma Department, M. Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw (Poland); Akkooi, Alexander C. J. van [Erasmus University Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands)

    2010-05-11

    Surgery remains the mainstay of melanoma therapy, regardless of the tumor site. Only the early diagnosis combined with proper surgical therapy currently gives patients affected by this malignancy the chance for a full cure. The main goal of surgical therapy is to provide the local control of the disease and to secure long-term survival of the patient without reasonable functional and esthetic impairment. The recommended method of biopsy—excisional biopsy, as an initial diagnostic and, to some extent, therapeutic procedure—is performed under local anesthesia as an elliptical incision with visual clear margins of 1–3 mm and with some mm of subcutaneous tissue. The extent of radical excision of the primary tumor (or scar after excisional biopsy) is based on the histopathologic characteristics of the primary tumor and usually consists of 1–2 cm margins with primary closure. The philosophy behind conducted randomized clinical trials has been to find the most conservative surgical approach that is able to guarantee the same results as more demolitive treatment. This has been the background of the trials designed to define the correct margins of excision around a primary cutaneous melanoma. Much less definition can be dedicated to the surgical management of patients with non-cutaneous melanomas.

  17. Surgery of Primary Melanomas

    International Nuclear Information System (INIS)

    Rutkowski, Piotr; Zdzienicki, Marcin; Nowecki, Zbigniew I.; Akkooi, Alexander C. J. van

    2010-01-01

    Surgery remains the mainstay of melanoma therapy, regardless of the tumor site. Only the early diagnosis combined with proper surgical therapy currently gives patients affected by this malignancy the chance for a full cure. The main goal of surgical therapy is to provide the local control of the disease and to secure long-term survival of the patient without reasonable functional and esthetic impairment. The recommended method of biopsy—excisional biopsy, as an initial diagnostic and, to some extent, therapeutic procedure—is performed under local anesthesia as an elliptical incision with visual clear margins of 1–3 mm and with some mm of subcutaneous tissue. The extent of radical excision of the primary tumor (or scar after excisional biopsy) is based on the histopathologic characteristics of the primary tumor and usually consists of 1–2 cm margins with primary closure. The philosophy behind conducted randomized clinical trials has been to find the most conservative surgical approach that is able to guarantee the same results as more demolitive treatment. This has been the background of the trials designed to define the correct margins of excision around a primary cutaneous melanoma. Much less definition can be dedicated to the surgical management of patients with non-cutaneous melanomas

  18. Primary intestinal lymphangiectasia.

    Science.gov (United States)

    Suresh, N; Ganesh, R; Sankar, Janani; Sathiyasekaran, Malathi

    2009-10-01

    Primary intestinal lymphangiectasia (PIL) is a rare disease of intestinal lymphatics presenting with hypoproteinemia, bilateral lower limb edema, ascites, and protein losing enteropathy. We report a series of 4 children from Chennai, India presenting with anasarca, recurrent diarrhea, hypoproteinemia and confirmatory features of PIL on endoscopy and histopathology.

  19. Healthcare is primary

    Directory of Open Access Journals (Sweden)

    Raman Kumar

    2015-01-01

    Full Text Available India is undergoing a rapid transformation in terms of governance, administrative reforms, newer policy develoment, and social movements. India is also considered one of the most vibrant economies in the world. The current discourse in public space is dominated by issues such as economic development, security, corruption free governance, gender equity, and women safety. Healthcare though remains a pressing need of population; seems to have taken a backseat. In the era of decreasing subsidies and cautious investment in social sectors, the 2 nd National Conference on Family Medicine and Primary Care 2015 (FMPC brought a focus on "healthcare" in India. The theme of this conference was "Healthcare is Primary." The conference participants discussed on the theme of why healthcare should be a national priority and why strong primary care should remain at the center of healthcare delivery system. The experts recommended that India needs to strengthen the "general health system" instead of focusing on disease based vertical programs. Public health system should have capacity and skill pool to be able to deliver person centered comprehensive health services to the community. Proactive implementation of policies towards human resource in health is the need of the hour. As the draft National Health Policy 2015 is being debated, "family medicine" (academic primary care, the unfinished agenda of National Health Policy 2002, remains a priority area of implementation.

  20. Multiple Primary Tumors

    African Journals Online (AJOL)

    2018-02-07

    Feb 7, 2018 ... breast and ascending colon. KEYWORDS: Carcinoid, colorectal cancer, metachronous, synchronous. Multiple Primary Tumors. MA Adeyanju, AA Ilori. Address for correspondence: Dr. MA Adeyanju,. Department of Surgery, Federal Medical Centre, Ebute Metta,. Lagos, Nigeria. E-mail: mbadeyanju@yahoo.

  1. Primary malignant intramedullary lymphoma

    International Nuclear Information System (INIS)

    Orrego P, E.; Heinicke Y, H.; Arbaiza A, D.; Yepez R, V.

    1999-01-01

    A case of primary malignant intramedullary lymphoma, localized in the dorsal part of the spinal cord is presented. The clinical symptoms were associated with motor and sensitive deficit. Clinical investigations excluded the presence of lymphoma in other locations in the central nervous system and the extra neural organs. Postoperative radiotherapy and chemotherapy improved relict neurological symptoms. (authors)

  2. Primary black holes

    International Nuclear Information System (INIS)

    Novikov, I.; Polnarev, A.

    1981-01-01

    Proves are searched for of the formation of the so-called primary black holes at the very origin of the universe. The black holes would weigh less than 10 13 kg. The formation of a primary black hole is conditional on strong fluctuations of the gravitational field corresponding roughly to a half of the fluctuation maximally permissible by the general relativity theory. Only big fluctuations of the gravitational field can overcome the forces of the hot gas pressure and compress the originally expanding matter into a black hole. Low-mass black holes have a temperature exceeding that of the black holes formed from stars. A quantum process of particle formation, the so-called evaporation takes place in the strong gravitational field of a black hole. The lower the mass of the black hole, the shorter the evaporation time. The analyses of processes taking place during the evaporation of low-mass primary black holes show that only a very small proportion of the total mass of the matter in the universe could turn into primary black holes. (M.D.)

  3. Familial primary hyperparathyroidism

    International Nuclear Information System (INIS)

    Iqbal, P.; Javed, R.

    2007-01-01

    A case of primary hyperparathyroidism in a 17 years old female is described. Patient presented with severe abdominal and pelvic pains associate with discomfort. Diagnostic testing revealed multiple upper and lower limb fractures and renal stones. Case was self limiting. Patient's condition resolved on parathyroidectomy for adenoma and partial thyroidectomy. Follow-up showed familial links. (author)

  4. Multiple Primary Cancer Monograph

    Science.gov (United States)

    To identify groups of cancer survivors that are at increased risk for multiple primary cancers, investigators led an effort to provide the first comprehensive population-based analysis of the risk of subsequent cancer in the U.S., resulting in a monograph.

  5. Primary cosmic ray flux

    Energy Technology Data Exchange (ETDEWEB)

    Stanev, Todor

    2001-05-01

    We discuss the primary cosmic ray flux from the point of view of particle interactions and production of atmospheric neutrinos. The overall normalization of the cosmic ray flux and its time variations and site dependence are major ingredients of the atmospheric neutrino predictions and the basis for the derivation of the neutrino oscillation parameters.

  6. in primary care

    African Journals Online (AJOL)

    Claire van Deventer

    Keywords: child HIV, doctor involvement, primary health care, quality improvement ... expertise increased, PHC facilities are now expected to be able to .... organised patient documentation were revisited. .... Review: what can we learn from quality ... South Pacific: Review of evidence and lessons from an innovative.

  7. [Primary and secondary encopresis].

    Science.gov (United States)

    Lang-Langer, Ellen

    2007-01-01

    While the difficulty of the child to part with its faeces in primary encopresis is linked to the incapability to experience the object as separated and independent from himself, secondary encopresis is a progressed psychical state of development. In this case we have to deal with regression caused by conflict. Two case-studies show clearly the differences.

  8. Influence of Blend Morphology and Energetics on Charge Separation and Recombination Dynamics in Organic Solar Cells Incorporating a Nonfullerene Acceptor

    KAUST Repository

    Cha, Hyojung; Wheeler, Scot; Holliday, Sarah; Dimitrov, Stoichko D.; Wadsworth, Andrew; Lee, Hyun Hwi; Baran, Derya; McCulloch, Iain; Durrant, James R.

    2017-01-01

    Nonfullerene acceptors (NFAs) in blends with highly crystalline donor polymers have been shown to yield particularly high device voltage outputs, but typically more modest quantum yields for photocurrent generation as well as often lower fill factors (FF). In this study, we employ transient optical and optoelectronic analysis to elucidate the factors determining device photocurrent and FF in blends of the highly crystalline donor polymer PffBT4T-2OD with the promising NFA FBR or the more widely studied fullerene acceptor PC71BM. Geminate recombination losses, as measured by ultrafast transient absorption spectroscopy, are observed to be significantly higher for PffBT4T-2OD:FBR blends. This is assigned to the smaller LUMO-LUMO offset of the PffBT4T-2OD:FBR blends relative to PffBT4T-2OD:PC71BM, resulting in the lower photocurrent generation efficiency obtained with FBR. Employing time delayed charge extraction measurements, these geminate recombination losses are observed to be field dependent, resulting in the lower FF observed with PffBT4T-2OD:FBR devices. These data therefore provide a detailed understanding of the impact of acceptor design, and particularly acceptor energetics, on organic solar cell performance. Our study concludes with a discussion of the implications of these results for the design of NFAs in organic solar cells.

  9. Spectroscopic signatures of spin-charge separation in the quasi-one-dimensional organic conductor TTF-TCNQ

    DEFF Research Database (Denmark)

    Claessen, R.; Sing, M.; Schwingenschlogl, U.

    2002-01-01

    The electronic structure of the quasi-one-dimensional organic conductor TTF-TCNQ is studied by angle-resolved photoelectron spectroscopy (ARPES). The experimental spectra reveal significant discrepancies to band theory. We demonstrate that the measured dispersions can be consistently mapped onto...

  10. In search of chiral magnetic effect: separating flow-driven background effects and quantifying anomaly-induced charge separations

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xu-Guang [Physics Department and Center for Particle Physics and Field Theory, Fudan University, Shanghai 200433 (China); Yin, Yi [Physics Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Liao, Jinfeng [Physics Department and Center for Exploration of Energy and Matter, Indiana University, 2401 N Milo B. Sampson Lane, Bloomington, IN 47408 (United States); RIKEN BNL Research Center, Bldg. 510A, Brookhaven National Laboratory, Upton, NY 11973 (United States)

    2016-12-15

    We report our recent progress on the search of Chiral Magnetic Effect (CME) by developing new measurements as well as by hydrodynamic simulations of CME and background effects, with both approaches addressing the pressing issue of separating flow-driven background contributions and possible CME signal in current heavy ion collision measurements.

  11. The Effect of Ageing on Exciton Dynamics, Charge Separation, and Recombination in P3HT/PCBM Photovoltaic Blends

    NARCIS (Netherlands)

    Deschler, Felix; Sio, Antonietta De; von Hauff, Elizabeth; Kutka, Peter; Sauermann, Tobias; Egelhaaf, Hans-j; Hauch, Jens; Da Como, Enrico

    2012-01-01

    A study of how light-induced degradation influences the fundamental photophysical processes in the active layer of poly(3-hexylthiophene)/[6,6]-phenyl C61-butyric acid methyl ester (P3HT/PCBM) solar cells is presented. Non-encapsulated samples are systematically aged by exposure to AM 1.5

  12. Elucidating the Ultrafast Dynamics of Photoinduced Charge Separation in Metalloporphyrin-Fullerene Dyads Across the Electromagnetic Spectrum

    DEFF Research Database (Denmark)

    Zhang, J.; Pápai, Mátyás Imre; Hirsch, A.

    2016-01-01

    Metalloporphyrins are prominent building blocks in the synthetic toolbox of advanced photodriven molecular devices. When the central ion is paramagnetic, the relaxation pathways within the manifold of excited states are highly intricate so that unravelling the intramolecular energy and electron t...

  13. Influence of Blend Morphology and Energetics on Charge Separation and Recombination Dynamics in Organic Solar Cells Incorporating a Nonfullerene Acceptor

    KAUST Repository

    Cha, Hyojung

    2017-11-27

    Nonfullerene acceptors (NFAs) in blends with highly crystalline donor polymers have been shown to yield particularly high device voltage outputs, but typically more modest quantum yields for photocurrent generation as well as often lower fill factors (FF). In this study, we employ transient optical and optoelectronic analysis to elucidate the factors determining device photocurrent and FF in blends of the highly crystalline donor polymer PffBT4T-2OD with the promising NFA FBR or the more widely studied fullerene acceptor PC71BM. Geminate recombination losses, as measured by ultrafast transient absorption spectroscopy, are observed to be significantly higher for PffBT4T-2OD:FBR blends. This is assigned to the smaller LUMO-LUMO offset of the PffBT4T-2OD:FBR blends relative to PffBT4T-2OD:PC71BM, resulting in the lower photocurrent generation efficiency obtained with FBR. Employing time delayed charge extraction measurements, these geminate recombination losses are observed to be field dependent, resulting in the lower FF observed with PffBT4T-2OD:FBR devices. These data therefore provide a detailed understanding of the impact of acceptor design, and particularly acceptor energetics, on organic solar cell performance. Our study concludes with a discussion of the implications of these results for the design of NFAs in organic solar cells.

  14. Robust Inclusion Complexes of Crown Ether Fused Tetrathiafulvalenes with Li+@C-60 to Afford Efficient Photodriven Charge Separation

    DEFF Research Database (Denmark)

    Supur, M.; Kawashima, Y.; Larsen, K. R.

    2014-01-01

    ) obtained by UV/Vis titrations in benzonitrile (PhCN) at room temperature. On the basis of DFT studies at the B3LYP/6-311G(d,p) level, the orbital interactions between the crown ether moieties and the p surface of the fullerene together with the endohedral Li+ have a crucial role in robust complex formation...

  15. Design principle for efficient charge separation at the donor-acceptor interface for high performance organic solar cell device

    Science.gov (United States)

    Nie, Wanyi; Gupta, Gautam; Crone, Brian; Wang, Hsing-Lin; Mohite, Aditya; MPA-11 Material synthesis and integrated device Team; MPA-chemistry Team

    2014-03-01

    The performance of donor (D) /acceptor (A) structure based organic electronic devices, such as solar cell, light emitting devices etc., relays on the charge transfer process at the interface dramatically. In organic solar cell, the photo-induced electron-hole pair is tightly bonded and will form a charge transfer (CT) state at the D/A interface after dissociation. There is a large chance for them to recombine through CT state and thus is a major loss that limit the overall performance. Here, we report three different strategies that allow us to completely suppress the exciplex (or charge transfer state) recombination between any D/A system. We observe that the photocurrent increases by 300% and the power conversion efficiency increases by 4-5 times simply by inserting a spacer layer in the form of an a) insulator b) Oliogomer or using a c) heavy atom at the donor-acceptor interface in a P3HT/C60 bilayer device. By using those different functional mono layers, we successfully suppressed the exciplex recombination in evidence of increased photocurrent and open circuit voltage. Moreover, these strategies are applicable universally to any donor-acceptor interface. And we demonstrated such strategies in a bulk-heterojunction device which improved the power conversion efficiency from 3.5% up to 4.6%.

  16. Determination of the excitation migration time in Photosystem II consequences for the membrane organization and charge separation parameters

    NARCIS (Netherlands)

    Broess, K.; Trinkunas, G.; Hoek, van A.; Croce, R.; Amerongen, van H.

    2008-01-01

    The fluorescence decay kinetics of Photosystem II (PSII) membranes from spinach with open reaction centers (RCs), were compared after exciting at 420 and 484 nm. These wavelengths lead to preferential excitation of chlorophyll (Chl) a and Chl b, respectively, which causes different initial

  17. Determination of the excitation migration time in Photosystem II - Consequences for the membrane organization and charge separation parameters

    NARCIS (Netherlands)

    Broess, Koen; Trinkunas, Gediminas; van Hoek, Arie; Croce, Roberta; van Amerongen, Herbert

    The fluorescence decay kinetics of Photosystem II (PSII) membranes from spinach with open reaction centers (RCs), were compared after exciting at 420 and 484 nm. These wavelengths lead to preferential excitation of chlorophyll (Chl) a and Chl b, respectively, which causes different initial

  18. Determination of the excitation migration time in Photosystem II. Consequences for the membrane organization and charge separation parameters

    NARCIS (Netherlands)

    Broess, Koen; Trinkunas, Gediminas; van Hoek, Arie; Croce, Roberta; van Amerongen, Herbert

    The fluorescence decay kinetics of Photosystem II (PSII) membranes from spinach with open reaction centers (RCs), were compared after exciting at 420 and 484 nm. These wavelengths lead to preferential excitation of chlorophyll (Chl) a and Chl b, respectively, which causes different initial

  19. Photodynamics of charge separation and recombination in solid alternating films of phthalocyanine or phthalocyanine-fullerene dyad and perylene dicarboximide

    NARCIS (Netherlands)

    Lehtivuori, Heli; Kumpulainen, Tatu; Hietala, Matti; Efimov, Alexander; Helge, Lemmetyinen; Kira, Aiko; Imahori, Hiroshi; Tkachenko, Nikolai V.

    2009-01-01

    Alternate bilayer structures of N,N'-bis(2,5-di-tert-butylphenyl)-3,4,9,10- perylene dicarboximide (PDI), freebase phthalocyanines (Pc), and double-linked free-base phthalocyanine-fullerene dyad (Pc-C 60) were prepared by the Langmuir-Schäfer method and studied using a range of optical spectroscopy

  20. Long-Lived Charge Separation at Heterojunctions between Semiconducting Single-Walled Carbon Nanotubes and Perylene Diimide Electron Acceptors

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hyun Suk [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Arias, Dylan H [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Blackburn, Jeffrey L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sisto, Thomas J. [Columbia University; Peurifoy, Samuel [Columbia University; Zhang, Boyuan [Columbia University; Nuckolls, Colin [Columbia University

    2018-04-13

    Nonfullerene electron acceptors have facilitated a recent surge in the efficiencies of organic solar cells, although fundamental studies of the nature of exciton dissociation at interfaces with nonfullerene electron acceptors are still relatively sparse. Semiconducting single-walled carbon nanotubes (s-SWCNTs), unique one-dimensional electron donors with molecule-like absorption and highly mobile charges, provide a model system for studying interfacial exciton dissociation. Here, we investigate excited-state photodynamics at the heterojunction between (6,5) s-SWCNTs and two perylene diimide (PDI)-based electron acceptors. Each of the PDI-based acceptors, hPDI2-pyr-hPDI2 and Trip-hPDI2, is deposited onto (6,5) s-SWCNT films to form a heterojunction bilayer. Transient absorption measurements demonstrate that photoinduced hole/electron transfer occurs at the photoexcited bilayer interfaces, producing long-lived separated charges with lifetimes exceeding 1.0 us. Both exciton dissociation and charge recombination occur more slowly for the hPDI2-pyr-hPDI2 bilayer than for the Trip-hPDI2 bilayer. To explain such differences, we discuss the potential roles of the thermodynamic charge transfer driving force available at each interface and the different molecular structure and intermolecular interactions of PDI-based acceptors. Detailed photophysical analysis of these model systems can develop the fundamental understanding of exciton dissociation between organic electron donors and nonfullerene acceptors, which has not been systematically studied.

  1. Studies on density dependence of charge separation in a direct energy converter using slanted Cusp magnetic field

    International Nuclear Information System (INIS)

    Munakata, Yoshiro; Kawaguchi, Takashi; Takeno, Hiromasa; Yasaka, Yasuyoshi; Ichimura, Kazuya; Nakashima, Yousuke

    2012-01-01

    In an advanced fusion, fusion-produced charged particles must be separated from each other for efficient energy conversion to electricity. The CuspDEC performs this function of separation and direct energy conversion. Analysis of working characteristics of CuspDEC on plasma density is an important subject. This paper summarizes and discusses experimental and theoretical works for high density plasma by using a small scale experimental device employing a slanted cusp magnetic field. When the incident plasma is low-density, good separation of the charged particles can be accomplished and this is explained by the theory based on a single particle motion. In high density plasma, however, this theory cannot be always applied due to space charge effects. In the experiment, as gradient of the field line increases, separation capability of the charged particles becomes higher. As plasma density becomes higher, however, separation capability becomes lower. This can be qualitatively explained by using calculations of the modified Störmer potential including space charge potential. (author)

  2. Parameters influencing charge separation in solid-state dye-sensitized solar cells using novel hole conductors

    NARCIS (Netherlands)

    Kroeze, J.E.; Hirata, N.; Schmidt-Mende, L.; Orizu, C.; Ogier, S.D.; Carr, K.; Grätzel, M.; Durrant, J.R.

    2006-01-01

    Solid-state dye-sensitized solar cells employing a solid organic hole-transport material (HTM) are currently under intensive investigation, since they offer a number of practical advantages over liquid-electrolyte junction devices. Of particular importance to the design of such devices is the

  3. Charge separation dynamics in a narrow band gap polymer-PbS nanocrystal blend for efficient hybrid solar cells

    NARCIS (Netherlands)

    Piliego, Claudia; Manca, Marianna; Kroon, Renee; Yarema, Maksym; Szendrei, Krisztina; Andersson, Mats R.; Heiss, Wolfgang; Loi, Maria A.

    2012-01-01

    We have demonstrated efficient hybrid solar cells based on lead sulfide (PbS) nanocrystals and a narrow band gap polymer, poly[{2,5-bis(2-hexyldecyl)-2,3,5,6-tetrahydro-3,6-dioxopyrrolo[3,4-c]pyrrole-1,4-diyl}-alt-{[2,2'-(1,4-phenylene)bis-thiophene]-5,5'-diyl}], (PDPPTPT). An opportune mixing of

  4. Charge separation dynamics in a narrow band gap polymer-PbS nanocrystal blend for efficient hybrid solar cells

    OpenAIRE

    Piliego, Claudia; Manca, Marianna; Kroon, Renee; Yarema, Maksym; Szendrei, Krisztina; Andersson, Mats R.; Heiss, Wolfgang; Loi, Maria A.

    2012-01-01

    We have demonstrated efficient hybrid solar cells based on lead sulfide (PbS) nanocrystals and a narrow band gap polymer, poly[{2,5-bis(2-hexyldecyl)-2,3,5,6-tetrahydro-3,6-dioxopyrrolo[3,4-c]pyrrole-1,4-diyl}-alt-{[2,2'-(1,4-phenylene)bis-thiophene]-5,5'-diyl}], (PDPPTPT). An opportune mixing of the two materials led to the formation of an energetically favorable bulk hetero-junction with a broad spectral response. Using a basic device structure, we reached a power conversion efficiency of s...

  5. Improved solar light stimulated charge separation of g-C3N4 through self-altering acidic treatment

    Science.gov (United States)

    Leong, Kah Hon; Lim, Ping Feng; Sim, Lan Ching; Punia, Varun; Pichiah, Saravanan

    2018-02-01

    Herein, we report the use of acid treatment to treat g-C3N4 nanostructured by a direct and facile synthesis route. The adopted treatment enhanced photoactivity of g-C3N4 and reflected in the removal of recalcitrant organic pollutant, Bisphenol A under direct sunlight. A complete removal of Bisphenol A was attained in a short duration (225 min) as compared to pure g-C3N4. The analysis clearly substantiated the robustness of acid exfoliation that promoted a blue shift, extended the conjugated length of its respective conduction and valance band. It also drastically prolonged the recombination rate of charge carriers, by producing excess of unpaired electrons in the conduction band for active radicals' generation. Thus, this new findings could offer a new sight of self-alteration in improving the photoactivity of complex organic pollutants for sustainable environmental remediation.

  6. Imaging intraflagellar transport in mammalian primary cilia.

    Science.gov (United States)

    Besschetnova, Tatiana Y; Roy, Barnali; Shah, Jagesh V

    2009-01-01

    The primary cilium is a specialized organelle that projects from the surface of many cell types. Unlike its motile counterpart it cannot beat but does transduce extracellular stimuli into intracellular signals and acts as a specialized subcellular compartment. The cilium is built and maintained by the transport of proteins and other biomolecules into and out of this compartment. The trafficking machinery for the cilium is referred to as IFT or intraflagellar transport. It was originally identified in the green algae Chlamydomonas and has been discovered throughout the evolutionary tree. The IFT machinery is widely conserved and acts to establish, maintain, and disassemble cilia and flagella. Understanding the role of IFT in cilium signaling and regulation requires a methodology for observing it directly. Here we describe current methods for observing the IFT process in mammalian primary cilia through the generation of fluorescent protein fusions and their expression in ciliated cell lines. The observation protocol uses high-resolution time-lapse microscopy to provide detailed quantitative measurements of IFT particle velocities in wild-type cells or in the context of genetic or other perturbations. Direct observation of IFT trafficking will provide a unique tool to dissect the processes that govern cilium regulation and signaling. 2009 Elsevier Inc. All rights reserved.

  7. American surgery and the Affordable Care Act.

    Science.gov (United States)

    Stain, Steven C; Hoyt, David B; Hunter, John G; Joyce, Geoffrey; Hiatt, Jonathan R

    2014-09-01

    The Affordable Care Act (ACA) attempts to change the way we finance and deliver health care by coordinating the delivery of primary, specialty, and hospital services in accountable care organizations. The ways in which accountable care organizations will develop and evolve is unclear; however, the effects on surgeons and their patients will be substantial. High-value care in the ACA emphasizes quality, safety, resource use and appropriateness, and the patient's experience of care. Payment will be linked to these principles. Department chairs overseeing a clinical enterprise in academic medical centers now must add financial and quality measures to the traditional missions of education, research, and clinical service. At a time when surgical training is in dramatic evolution, with work hour limitations for residents and an emphasis on quality, productivity, and increasing oversight of trainees for faculty, residency programs will need to meet the increasing demands of an aging population and newly insured patients under the ACA. The American College of Surgeons, with its century-long commitment to quality improvement, research-based standards, and performance measurement and verification, has begun its Inspiring Quality Campaign, is developing new educational tools, and is preparing proposals for payment reform based on surgeons' participation in quality programs.

  8. Local policies for DSM: the UK's home energy conservation act

    International Nuclear Information System (INIS)

    Jones, E.; Leach, M.

    2000-01-01

    Residential energy use accounts for approximately 28 per cent of total primary energy use in the UK, with consumption in this sector forecast to increase due partly to expanding numbers of households. Finding ways to reduce residential energy consumption must form a key part of the climate change strategies of the UK and all developed countries. In 1995, an innovative piece of legislation was passed in the UK, devolving residential energy efficiency responsibility to local government. Under 'The Home Energy Conservation Act' (HECA), local authorities are obliged to consider the energy efficiency of private as well as public housing stock. Authorities were given a duty to produce a strategy for improving residential energy efficiency in their area by 30 per cent in the next 10-15 years. This paper describes the enormous variation in the quality of local authorities' strategies and discusses reasons for this variation. Based on a nationwide survey of HECA lead officers, it considers the opportunities and constraints facing local authorities, and what has been achieved to-date under the Act. It also examines how HECA fits into the UK's national energy policy and explains the roles of other institutions across the public, private and voluntary sector in facilitating implementation of the Act. Finally, the paper considers how other countries can learn from the UK's HECA experience and can use the Act as a template to apply the principle of subsidiarity to this area of environmental policy. (Author)

  9. Modification as a propositional act

    DEFF Research Database (Denmark)

    Rijkhoff, Jan

    2014-01-01

    A complete functional theory of grammar should be able to specify the communicative function of each constituent in a sentence (or rather ‘Discourse Act’). Whereas predicating and referring have been given due attention in functional approaches to grammar, the modifying function of linguistic...... material in a Discourse Act has been largely ignored. This chapter argues (i) that modifying is no less actional than predicating or referring in the process of verbal communication and (ii) that the modifying function of linguistic material should be specified at the highest level of representation...

  10. Fast-acting valve actuator

    Science.gov (United States)

    Cho, Nakwon

    1980-01-01

    A fast-acting valve actuator utilizes a spring driven pneumatically loaded piston to drive a valve gate. Rapid exhaust of pressurized gas from the pneumatically loaded side of the piston facilitates an extremely rapid piston stroke. A flexible selector diaphragm opens and closes an exhaust port in response to pressure differentials created by energizing and de-energizing a solenoid which controls the pneumatic input to the actuator as well as selectively providing a venting action to one side of the selector diaphragm.

  11. The European Model Company Act

    DEFF Research Database (Denmark)

    Cleff, Evelyne Beatrix

    2011-01-01

    European Company Law regulation is currently undergoing a reform. These reforms raise a number of regulatory questions, such as what should be the aims of companies' legislation, and how these aims should best be met by regulation. Many of the reforms and discussions (both on EU and national level...... an increasing influence on the framing of company legislation, such as the choice between mandatory or default rules. This article introduces the project 'European Company Law and the choice of Regulatory Method' which is carried out in collaboration with the 'European Model Company Act Group'. The project aims...

  12. Spirometry in primary care

    Science.gov (United States)

    Coates, Allan L; Graham, Brian L; McFadden, Robin G; McParland, Colm; Moosa, Dilshad; Provencher, Steeve; Road, Jeremy

    2013-01-01

    Canadian Thoracic Society (CTS) clinical guidelines for asthma and chronic obstructive pulmonary disease (COPD) specify that spirometry should be used to diagnose these diseases. Given the burden of asthma and COPD, most people with these diseases will be diagnosed in the primary care setting. The present CTS position statement was developed to provide guidance on key factors affecting the quality of spirometry testing in the primary care setting. The present statement may also be used to inform and guide the accreditation process for spirometry in each province. Although many of the principles discussed are equally applicable to pulmonary function laboratories and interpretation of tests by respirologists, they are held to a higher standard and are outside the scope of the present statement. PMID:23457669

  13. Cancer of unknown primary

    DEFF Research Database (Denmark)

    Dyrvig, Anne-Kirstine; Yderstræde, Knud Bonnet; Gerke, Oke

    2017-01-01

    210 (38.7%) had a CUP diagnosis confirmed. Within the cohort, 347 patients (64.0%) had a registration in CR matching with the NPR registration. Exposure to diagnostic procedures included biopsy (n = 439, 81.0%) and image modalities (n = 532, 98.2%). Survival was poor with 67 (12.4%) individuals alive...... after 4 years.The validity of a CUP diagnosis in NPR was low when using data from CR as reference. More than half the suspected CUP patients had a previous cancer diagnosis with CUP being the most frequent. Patients were diagnosed in compliance with guidelines indicating high external validity, but less...... than 1 quarter had their primary identified and the 1-year survival was approximately 20%. Research is needed to develop efficacious methods for primary detection....

  14. Primary omental pregnancy

    International Nuclear Information System (INIS)

    Yildizhan, R.; Kurdoglu, M.; Kolusari, A.; Erten, R.

    2008-01-01

    Omental pregnancy is a rare form of ectopic pregnancy and can be seen primarily or secondary to a tubal pregnancy. A 25-yeal-old woman presented with abdominal distention with pain and anemia without vaginal bleeding. After a provisional diagnosis of ruptured ectopic pregnancy, laparotomy was performed. On surgical exploration, the bilateral tubes and ovaries were intact, however, an omental pregnancy was detected as the cause of hemoperitoneum. Partial omentectomy was performed. Although most cases are secondary, presented here is an additional case of primary omental pregnancy at 12 weeks according to Studdiford's criteria. Histological evidence of neovascularization into the supporting tissue confirmed our diagnosis. A primary omental pregnancy should always be considered as a possible explanation for severe hemoperitoneum in ectopic pregnancies presenting with acute abdomen and with intact adnexes on surgical exploration. (author)

  15. Basics of primary immunodeficiencies

    Directory of Open Access Journals (Sweden)

    Claudia Hernández-Martínez

    2016-05-01

    Full Text Available Primary immunodeficiencies (PID are a heterogeneous group of inherited disorders, the etiology are the defects in the development or function of the immune system. The principal PID manifestations are the infections in early age, malignancy and diseases of immune dysregulation as autoimmunity and allergy. PIDs are genetics disorders and most of them are inherited as autosomal recessive, also this group of diseases is more prevalent in males and in childhood. The antibody immunodeficiency is the PID more common in adults. The more frequent disorders are the infections in the respiratory tract, abscesses, candidiasis, diarrhea, BCGosis etc. Initial approach included a complete blood count and quantification of immunoglobulins. The delay in diagnosis could be explained due to a perception that the recurrent infections are normal process or think that they are exclusively of childhood. The early diagnosis of PID by primary care physicians is important to opportune treatment and better prognosis.

  16. 77 FR 39749 - Sunshine Act Meeting

    Science.gov (United States)

    2012-07-05

    ... advertising in securities offerings conducted pursuant to Rule 506 of Regulation D under the Securities Act... Startups Act. At times, changes in Commission priorities require alterations in the scheduling of meeting...

  17. 75 FR 11565 - Sunshine Act Meetings

    Science.gov (United States)

    2010-03-11

    ... NATIONAL COUNCIL ON DISABILITY Sunshine Act Meetings Type: Quarterly Meeting. Dates and Times.... Agenda: Public Comment Sessions; Emergency Management; Developmental Disabilities and Bill of Rights Act, International Development, National Summit on Disability Policy 2010, United States Marine Corps Research...

  18. Clean Water Act Section 404 and Agriculture

    Science.gov (United States)

    The U.S. Department of Agriculture (USDA) and EPA have longstanding programs to promote water quality and broader environmental goals identified in both the Agriculture Act of 2014 and the Clean Water Act.

  19. 7 CFR 1209.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE MUSHROOM PROMOTION, RESEARCH, AND CONSUMER INFORMATION ORDER Mushroom Promotion, Research, and Consumer Information Order Definitions § 1209.1 Act. Act...

  20. 7 CFR 1215.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE POPCORN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Popcorn Promotion, Research, and Consumer Information Order Definitions § 1215.1 Act. Act means...

  1. 7 CFR 1230.1 - Act.

    Science.gov (United States)

    2010-01-01

    ... the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE PORK PROMOTION, RESEARCH, AND CONSUMER INFORMATION Pork Promotion, Research, and Consumer Information Order Definitions § 1230.1 Act. Act means the...

  2. [Primary care in France].

    Science.gov (United States)

    Sánchez-Sagrado, T

    2016-01-01

    The poor planning of health care professionals in Spain has led to an exodus of doctors leaving the country. France is one of the chosen countries for Spanish doctors to develop their professional career. The French health care system belongs to the Bismarck model. In this model, health care system is financed jointly by workers and employers through payroll deduction. The right to health care is linked to the job, and provision of services is done by sickness-funds controlled by the Government. Primary care in France is quite different from Spanish primary care. General practitioners are independent workers who have the right to set up a practice anywhere in France. This lack of regulation has generated a great problem of "medical desertification" with problems of health care access and inequalities in health. French doctors do not want to work in rural areas or outside cities because "they are not value for money". Medical salary is linked to professional activity. The role of doctors is to give punctual care. Team work team does not exist, and coordination between primary and secondary care is lacking. Access to diagnostic tests, hospitals and specialists is unlimited. Duplicity of services, adverse events and inefficiencies are the norm. Patients can freely choose their doctor, and they have a co-payment for visits and hospital care settings. Two years training is required to become a general practitioner. After that, continuing medical education is compulsory, but it is not regulated. Although the French medical Health System was named by the WHO in 2000 as the best health care system in the world, is it not that good. While primary care in Spain has room for improvement, there is a long way for France to be like Spain. Copyright © 2015 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

  3. [Primary care in Italy].

    Science.gov (United States)

    Sánchez-Sagrado, T

    Italy is not a country where Spanish doctors emigrate, as there is an over-supply of health care professionals. The Italian Servizio Sanitario Nazionale has some differences compared to the Spanish National Health System. The Servizio Sanitario Nazionale is financed by national and regional taxes and co-payments. There are taxes earmarked for health, and Primary Care receives 50% of the total funds. Italian citizens and residents in Italy have the right to free health cover. However, there are co-payments for laboratory and imaging tests, pharmaceuticals, specialist ambulatory services, and emergencies. Co-payments vary in the different regions. The provision of services is regional, and thus fragmentation and major inequities are the norm. Doctors in Primary Care are self-employed and from 2000 onwards, there are incentives to work in multidisciplinary teams. Salary is regulated by a national contract and it is the sum of per-capita payments and extra resources for specific activities. Responsibilities are similar to those of Spanish professionals. However, medical care is more personal. Relationships between Primary Care and specialised care depend on the doctors' relationships. Primary Care doctors are gatekeepers for specialised care, except for gynaecology, obstetrics and paediatrics. Specialised training is compulsory in order to work as general practitioner. The Italian Health Care System is a national health system like the Spanish one. However, health care professionals are self-employed, and there are co-payments. In spite of co-payments, Italians have one of the highest average life expectancy, and they support a universal and publicly funded health-care system. Copyright © 2017 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Primary Tunnel Junction Thermometry

    International Nuclear Information System (INIS)

    Pekola, Jukka P.; Holmqvist, Tommy; Meschke, Matthias

    2008-01-01

    We describe the concept and experimental demonstration of primary thermometry based on a four-probe measurement of a single tunnel junction embedded within four arrays of junctions. We show that in this configuration random sample specific and environment-related errors can be avoided. This method relates temperature directly to Boltzmann constant, which will form the basis of the definition of temperature and realization of official temperature scales in the future

  5. Primary stabbing headache.

    Science.gov (United States)

    Pareja, Juan A; Sjaastad, Ottar

    2010-01-01

    Primary stabbing headache is characterized by transient, cephalic ultrashort stabs of pain. It is a frequent complaint with a prevalence of 35.2%, a female preponderance, and a mean age of onset of 28 years (Vågå study). Attacks are generally characterized by moderate to severe, jabbing or stabbing pain, lasting from a fraction of a second to 3s. Attack frequency is generally low, with one or a few attacks per day. The paroxysms generally occur spontaneously, during daytime. Most patients exhibit a sporadic pattern, with an erratic, unpredictable alternation between symptomatic and non-symptomatic periods. Paroxysms are almost invariably unilateral. Temporal and fronto-ocular areas are most frequently affected. Attacks tend to move from one area to another, in either the same or the opposite hemicranium. Jabs may be accompanied by a shock-like feeling and even by head movement - "jolts" -or vocalization. On rare occasions, conjunctival hemorrhage and monocular vision loss have been described as associated features. Primary stabbing headache may concur, synchronously or independently, with other primary headaches. In contrast to what is the case in adults, in childhood it is not usually associated with other headaches. Treatment is rarely necessary. Indomethacin, 75-150 mg daily, may seem to be of some avail. Celecoxib, nifedipine, melatonin, and gabapentin have been reported to be effective in isolated cases and small series of patients. The drug studies need corroboration. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. ACTS TDMA network control. [Advanced Communication Technology Satellite

    Science.gov (United States)

    Inukai, T.; Campanella, S. J.

    1984-01-01

    This paper presents basic network control concepts for the Advanced Communications Technology Satellite (ACTS) System. Two experimental systems, called the low-burst-rate and high-burst-rate systems, along with ACTS ground system features, are described. The network control issues addressed include frame structures, acquisition and synchronization procedures, coordinated station burst-time plan and satellite-time plan changes, on-board clock control based on ground drift measurements, rain fade control by means of adaptive forward-error-correction (FEC) coding and transmit power augmentation, and reassignment of channel capacities on demand. The NASA ground system, which includes a primary station, diversity station, and master control station, is also described.

  7. 34 CFR 5.1 - Act.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Act. 5.1 Section 5.1 Education Office of the Secretary...-10) Definitions § 5.1 Act. As used in this part, Act means section 552 of title 5, United States Code, as amended by Pub. L. 90-23, codifying the Act of July 4, 1966, sometimes referred to as the “Freedom...

  8. 7 CFR 1205.10 - Act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Act. 1205.10 Section 1205.10 Agriculture Regulations... for Conduct of Sign-up Period Definitions § 1205.10 Act. The term Act means the Cotton Research and Promotion Act, as amended [7 U.S.C 2101-2118; Public Law 89-502, 80 Stat 279, as amended]. ...

  9. Global Warming Responses at the Primary Secondary Interface: 2. Potential Effectiveness of Education

    Science.gov (United States)

    Skamp, Keith; Boyes, Eddie; Stannistreet, Martin

    2009-01-01

    In an earlier paper (Skamp, Boyes, & Stanisstreet, 2009b), students' beliefs and willingness to act in relation to 16 specific actions related to global warming were compared across the primary secondary interface. More primary students believed in the effectiveness of most actions to reduce global warming and were willing to take those…

  10. [Primary headache and depression].

    Science.gov (United States)

    Gesztelyi, Gyöngyi

    2004-11-28

    Primary headaches--mainly tension-type headache and migraine--affect a significant portion of the population. Depression is also highly prevalent. The co-existence of a primary headache and depression in the same patient therefore might be a coincidence due to the high prevalence of these conditions, but there might be a causal relationship between them, or headaches and depression might have a common background. This review of the literature summarizes the features of the relationship between primary headaches and depression. Depression is more prevalent in headache patients than in the headache-free population. Prospective epidemiological studies suggest a common genetic, biochemical or environmental background behind primary headaches and depression. This theory is supported by the role of the same neurotransmitter systems (mostly serotonin and dopamine) in headaches as well as in depression. Comorbid depression is associated with female gender, higher age, and higher frequency of headaches. Most depression inventories--questionnaires used to screen for the severity of depressive symptoms--contain transdiagnostic items, therefore their use in their original form is limited in organic diseases: due to the somatic items they might overestimate the severity of depression. When examining a headache patient special attention should be paid to the recognition of comorbid depression. The diagnosis of suspected mood disorder could be supported by using simple screening methods, such as the original or the abbreviated versions of standard depression inventories, but the final diagnosis of major depression needs psychiatric evaluation. Quality of life of the headache patient is affected not only by the characteristics of pain (frequency, duration, severity) but also by the disability caused by headache and the associating mood disorder. Recognizing coexisting mood disorder and disability helps to make the best treatment choice for the acute and preventive treatment of

  11. 12 CFR 268.203 - Rehabilitation Act.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Rehabilitation Act. 268.203 Section 268.203... Rehabilitation Act. (a) Model employer. The Board shall be a model employer of individuals with disabilities. The... Rehabilitation Act of 1973, as amended (29 U.S.C. 791), has been violated in a complaint alleging nonaffirmative...

  12. 29 CFR 1614.203 - Rehabilitation Act.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false Rehabilitation Act. 1614.203 Section 1614.203 Labor... EMPLOYMENT OPPORTUNITY Provisions Applicable to Particular Complaints § 1614.203 Rehabilitation Act. (a... Rehabilitation Act of 1973, as amended (29 U.S.C. 791), has been violated in a complaint alleging nonaffirmative...

  13. 12 CFR 619.9000 - The Act.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false The Act. 619.9000 Section 619.9000 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM DEFINITIONS § 619.9000 The Act. The Farm Credit Act of 1971; Pub. L. 92-181 and amendments. ...

  14. 7 CFR 29.13 - The act.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false The act. 29.13 Section 29.13 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Regulations Definitions § 29.13 The act. The Tobacco Inspection Act, approved August 23, 1935. (7...

  15. 3 CFR - The Endangered Species Act

    Science.gov (United States)

    2010-01-01

    ... 3 The President 1 2010-01-01 2010-01-01 false The Endangered Species Act Presidential Documents Other Presidential Documents Memorandum of March 3, 2009 The Endangered Species Act Memorandum for the Heads of Executive Departments and Agencies The Endangered Species Act (ESA), 16 U.S.C. 1531 et seq...

  16. Allegheny County Clean Indoor Air Act Exemptions

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — List and location of all the businesses and social clubs who have received an exemption from the Pennsylvania Clean Indoor Air Act. “The Clean Indoor Air Act, Act...

  17. 76 FR 77558 - Sunshine Act Meeting; Notice

    Science.gov (United States)

    2011-12-13

    ... LEGAL SERVICES CORPORATION Sunshine Act Meeting; Notice DATES: Date and Time: The Legal Services Corporation's Operations & Regulations Committee will meet December 16, 2011. The meeting will commence at 4 p... Bylaws necessitated by the DC Nonprofit Corporation Act of 2010. 3. Public comment. 4. Consider and act...

  18. 31 CFR 0.216 - Privacy Act.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Privacy Act. 0.216 Section 0.216... RULES OF CONDUCT Rules of Conduct § 0.216 Privacy Act. Employees involved in the design, development, operation, or maintenance of any system of records or in maintaining records subject to the Privacy Act of...

  19. Acceptance and commitment therapy (ACT) for clinically distressed health care workers: Waitlist-controlled evaluation of an ACT workshop in a routine practice setting.

    Science.gov (United States)

    Waters, Cerith S; Frude, Neil; Flaxman, Paul E; Boyd, Jane

    2018-03-01

    To examine the effects of a 1-day acceptance and commitment therapy (ACT) workshop on the mental health of clinically distressed health care employees, and to explore ACT's processes of change in a routine practice setting. A quasi-controlled design, with participants block allocated to an ACT intervention or waiting list control group based on self-referral date. Participants were 35 health care workers who had self-referred for the ACT workshop via a clinical support service for staff. Measures were completed by ACT and control group participants at pre-intervention and 3 months post-intervention. Participants allocated to the waitlist condition went on to receive the ACT intervention and were also assessed 3 months later. At 3 months post-intervention, participants in the ACT group reported a significantly lower level of psychological distress compared to the control group (d = 1.41). Across the 3-month evaluation period, clinically significant change was exhibited by 50% of ACT participants, compared to 0% in the control group. When the control group received the same ACT intervention, 69% went on to exhibit clinically significant change. The ACT intervention also resulted in significant improvements in psychological flexibility, defusion, and mindfulness skills, but did not significantly reduce the frequency of negative cognitions. Bootstrapped mediation analyses indicated that the reduction in distress in the ACT condition was primarily associated with an increase in mindfulness skills, especially observing and non-reactivity. These findings provide preliminary support for providing brief ACT interventions as part of routine clinical support services for distressed workers. A 1-day ACT workshop delivered in the context of a routine staff support service was effective for reducing psychological distress among health care workers. The brief nature of this group intervention means it may be particularly suitable for staff support and primary care mental

  20. Macro Issues of Mikro Primary School

    Directory of Open Access Journals (Sweden)

    E Bray

    2007-05-01

    Full Text Available Mikro Primary School is an Afrikaans medium public school whose governing body refused to accede to an order of the Western Cape Department of Education to change the language policy of the school so as to convert it into a parallel medium Afrikaans/English school. The Supreme Court of Appeal held that section 29(2 of the Constitution of the Republic of South Africa, 1996, means that everyone has a right to be educated in an official language of his or her choice at a public educational institution to be provided by the State if reasonably practicable, but not the right to be so instructed at each and every public educational institution, subject only to it being reasonably practicable to do so. The court held that the language policy and admission policy of Mikro were not contrary to any provision of the Constitution, the South African Schools Act 84 of 1996, the Western Cape Provincial School Education Act 12 of 1997 or the Norms and Standards. The MEC and the department were prohibited and restrained from compelling or attempting to compel the school or its principal to admit learners for instruction otherwise than in compliance with its language policy and applicable provisions of the Schools Act and the Norms and Standards. The court declared the conduct of the department’s officials to be an unlawful interference with the government and professional management of the school in contravention of section 16 of the Schools Act and prohibited and restrained them from interfering unlawfully. The court rejected a previous interpretation of the term “organ of state” and relied on the Constitution which determines that any institution exercising a public power or performing a public function in terms of any legislation is an organ of state (section 239(b(ii. This means that the public school (acting through its governing body is clearly an organ of state because as an institution it exercises a public-education power and performs public

  1. Primary care training and the evolving healthcare system.

    Science.gov (United States)

    Peccoralo, Lauren A; Callahan, Kathryn; Stark, Rachel; DeCherrie, Linda V

    2012-01-01

    With growing numbers of patient-centered medical homes and accountable care organizations, and the potential implementation of the Patient Protection and Affordable Care Act, the provision of primary care in the United States is expanding and changing. Therefore, there is an urgent need to create more primary-care physicians and to train physicians to practice in this environment. In this article, we review the impact that the changing US healthcare system has on trainees, strategies to recruit and retain medical students and residents into primary-care internal medicine, and the preparation of trainees to work in the changing healthcare system. Recruitment methods for medical students include early preclinical exposure to patients in the primary-care setting, enhanced longitudinal patient experiences in clinical clerkships, and primary-care tracks. Recruitment methods for residents include enhanced ambulatory-care training and primary-care programs. Financial-incentive programs such as loan forgiveness may encourage trainees to enter primary care. Retaining residents in primary-care careers may be encouraged via focused postgraduate fellowships or continuing medical education to prepare primary-care physicians as both teachers and practitioners in the changing environment. Finally, to prepare primary-care trainees to effectively and efficiently practice within the changing system, educators should consider shifting ambulatory training to community-based practices, encouraging resident participation in team-based care, providing interprofessional educational experiences, and involving trainees in quality-improvement initiatives. Medical educators in primary care must think innovatively and collaboratively to effectively recruit and train the future generation of primary-care physicians. © 2012 Mount Sinai School of Medicine.

  2. Identification of a gene expression profile that discriminates indirect-acting genotoxins from direct-acting genotoxins

    Energy Technology Data Exchange (ETDEWEB)

    Hu Ting; Gibson, David P.; Carr, Gregory J.; Torontali, Suzanne M.; Tiesman, Jay P.; Chaney, Joel G.; Aardema, Marilyn J

    2004-05-18

    During the safety evaluation process of new drugs and chemicals, a battery of genotoxicity tests is conducted starting with in vitro genotoxicity assays. Obtaining positive results in in vitro genotoxicity tests is not uncommon. Follow-up studies to determine the biological relevance of positive genotoxicity results are costly, time consuming, and utilize animals. More efficient methods, especially for identifying a putative mode of action like an indirect mechanism of genotoxicity (where DNA molecules are not the initial primary targets), would greatly improve the risk assessment for genotoxins. To this end, we are participating in an International Life Sciences Institute (ILSI) project involving studies of gene expression changes caused by model genotoxins. The purpose of the work is to evaluate gene expression tools in general, and specifically for discriminating genotoxins that are direct-acting from indirect-acting. Our lab has evaluated gene expression changes as well as micronuclei (MN) in L5178Y TK{sup +/-} mouse lymphoma cells treated with six compounds. Direct-acting genotoxins (where DNA is the initial primary target) that were evaluated included the DNA crosslinking agents, mitomycin C (MMC) and cisplatin (CIS), and an alkylating agent, methyl methanesulfonate (MMS). Indirect-acting genotoxins included hydroxyurea (HU), a ribonucleotide reductase inhibitor, taxol (TXL), a microtubule inhibitor, and etoposide (ETOP), a DNA topoisomerase II inhibitor. Microarray gene expression analysis was conducted using Affymetrix mouse oligonucleotide arrays on RNA samples derived from cells which were harvested immediately after the 4 h chemical treatment, and 20 h after the 4 h chemical treatment. The evaluation of these experimental results yields evidence of differentially regulated genes at both 4 and 24 h time points that appear to have discriminating power for direct versus indirect genotoxins, and therefore may serve as a fingerprint for classifying chemicals

  3. Localization of primary aldosteronism

    International Nuclear Information System (INIS)

    Pagny, J.Y.; Chatellier, G.; Raynaud, A.; Plouin, P.F.; Corvol, P.

    1988-01-01

    After diagnosis of primary aldosteronism on the basis of biochemical evidence, the detection of the tumour is of crucial importance in the management of the disease. The efficacy of CT-Scan, Iodo-Cholesterol Scintigraphy, digitalized phlebography, adrenal vein sampling for steroid measurements (AVS), and Nuclear Magnetic Resonance (NMR) in 160 hypertensive patients with primary aldosteronism was reviewed. Diagnosis of Conn's adenoma (n=96) or Adrenal Hyperplasia (n=40) was confirmed by surgery or at least two concordant tumour localization tests. Scintigraphy gave a correct diagnosis in 53% of the 51 exams, CT-Scan in 82% of the 85 exams, and phlebography in 79% of 61 exams. Plasma Aldosterone/ Cortisol ratio was 5 times higher on the side of adenoma in 55% of the 47 cases but this ratio was also present in 23% of 22 patients with adrenal hyperplasia. Each procedure exhibited few false positive and false negative cases. NMR performed in 15 patients with Conn's adenoma identified all the cases. But tumours displayed a signal close to the liver signal and identical to the normal adrenal. These results and the risk of invasive procedure (failure of catheterization of the right adrenal vein (n=6) and adrenal haematoma (n=2) lead to propose a schema of exploration of patients with primary aldosteronism. The CT-Scan could be performed at the first step once the biological diagnosis confirmed. Phlebography and AVS will be performed only if tumour was less than 1 cm at the CT-Scan despite important biological abnormalities. This schema requires to be validated by a prospective evaluation [fr

  4. Teacher of primary English

    CERN Multimedia

    2003-01-01

    Part-time teacher of primary English needed for September 2003 to teach English National Curriculum (KS2) and NLS to mother tongue or good second language English-speakers aged 7-10. 4 hours contact time per week, team planning, marking and meetings. Candidates should be English mother tongue qualified teachers, confident, flexible classroom practitioners and team players. For further details and how to apply see http://enpferney.org/staff_vacancies.htm English National Programme, Lycée International, Ferney-Voltaire (http://enpferney.org/)

  5. Primary isolated hepatic tuberculosis

    International Nuclear Information System (INIS)

    Sheikh, A.S.F.; Qureshi, I.H.; Saba, K.; Bukhari, M.H.

    2013-01-01

    Isolated hepatic tuberculosis without pulmonary or bowel involvement is a diagnostic challenge and can cause considerable morbidity. A young lady from Lahore presented with fever, pain in right hypochondria, nausea and weight loss. CT scan of abdomen showed multiple small hypodense non-enhancing lesions and a heterogeneous texture of liver. Biopsy confirmed the diagnosis of hepatic tuberculosis. It was concluded a case of isolated hepatic tuberculosis without evidence of other primary sites involvement. It is important to consider tuberculosis in the differential diagnosis when suspecting lymphoproliferative or metastatic diseases in a patient with vague symptoms and abnormal hepatic texture on CT. (author)

  6. PRIMARY CARIES: AN OVERVIEW

    Directory of Open Access Journals (Sweden)

    Gaurav Solanki

    2012-01-01

    Full Text Available Primary caries is an initial lesions produced by direct extension from an external surface. Dental caries is called as tooth decay or a cavity is a disease in which bacterial processes changes carbohydrate to acid which than dematerializes the hard tooth structure like enamel, dentin and cementum. Streptococcus mutans and Lactobacillus are the bacteria responsible for the dental caries by acid production. This article throws light on the dental caries disease, its sign and symptoms, treatment and prevention of it. A review of some patents on dental caries is also provided that summarizes the recent technical advancements taken place in this area.

  7. Primary cutaneous lymphoma

    International Nuclear Information System (INIS)

    Nguyen, M. Connie; Cleary, Sean F.; Hoppe, Richard T.

    1995-01-01

    Purpose: A retrospective review analyzed the survival and freedom from relapse of patients with stage IE or IIE primary cutaneous lymphoma (non mycosis fungoides) after treatments with radiation therapy alone (XRT), chemotherapy alone (RX) or combined modality therapy (CMT). Methods and Materials: Fifty two patients with stage IE-IIE cutaneous lymphoma treated at Stanford University Hospital were reviewed. The median age was 57, with a range of 26 to 94 and a male to female ratio of 1.21:1. Patients were staged according to the Ann Arbor System. Pathology was classified according to the Working Formulation. Treatment outcomes were compared using Kaplan-Meier survival curves with a Gehan p-value test. Results: The follow up range was 6 months to 22 years (median 7 years.) Twenty one percent of patients had low grade, 63% had intermediate grade and 15% had high grade lymphoma. The most common histologic subtype was diffuse large cell lymphoma Thirty two patients received radiation alone as initial treatment and sixteen patients received combined modality as initial treatment. Four patients received chemotherapy alone. The only significant prognostic factor for survival was the stage at diagnosis. Patients with stage IE disease had a longer actuarial survival (5-yr=79%, 10-yr=71%), as compared to those with stage IIE (5-yr=49%, 10-yr=33%), (p=0.029). The only significant prognostic factor for freedom from relapse was the initial treatment. Initial combined modality treatment lead to a longer freedom from relapse compared to patients treated with radiation alone (p=0.002), (median 5 years vs. 1.2 years). Despite this, the actuarial overall survival in the combined modality group and the radiation alone group are similar (median survival 7.7 and 8 years). The efficacy of either radiation or chemotherapy as salvage treatment after radiation failure was equivalent and both salvage treatments lead to equally long survival and freedom from second relapse. Conclusion

  8. Bellefonte primary containment structure

    International Nuclear Information System (INIS)

    Olyniec, J.H.

    1981-01-01

    Construction of the reactor building primary containment structure at the Bellefonte Nuclear Plant involved several specialized construction techniques. This two unit plant is one of the nine nuclear units at six different sites now under construction by the Tennessee Valley Authority (TVA). The post-Tensioned, cast-in-place interior steel lined containment structure is unique within TVA. Problems during construction were identified at weekly planning meetings, and options were discussed. Close coordination between craft supervisors and on-site engineering personnel drew together ''hands-on''experience and technical background. Details of the construction techniques, problems, and solutions are presented

  9. Primary Carnitine Deficiency

    DEFF Research Database (Denmark)

    Rasmussen, Jan; Hougaard, David M; Sandhu, Noreen

    2017-01-01

    Primary carnitine deficiency (PCD) causes low levels of carnitine in patients potentially leading to metabolic and cardiac symptoms. Newborn screening for PCD is now routine in many countries by measuring carnitine levels in infants. In this study we report Apgar scores, length and weight...... scores, length and weight compared to controls. Newborns with PCD and newborns born to mothers with PCD had significantly lower levels of free carnitine (fC0) than controls. Screening algorithms focusing only on fC0 had a high rate of detection of newborns with PCD. Sample collection 4-9 days after birth...

  10. Aspirin for Primary Prevention.

    Science.gov (United States)

    Richman, Ilana B; Owens, Douglas K

    2017-07-01

    Aspirin reduces the risk of nonfatal myocardial infarction and stroke, and the risk of colorectal cancer. Aspirin increases the risk of gastrointestinal and intracranial bleeding. The best available evidence supports initiating aspirin in select populations. In 2016, the US Preventive Services Task Force recommended initiating aspirin for the primary prevention of both cardiovascular disease and colorectal cancer among adults ages 50 to 59 who are at increased risk for cardiovascular disease. Adults 60 to 69 who are at increased cardiovascular disease risk may also benefit. There remains considerable uncertainty about whether younger and older patients may benefit. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Primary cutaneous lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, M Connie; Cleary, Sean F; Hoppe, Richard T

    1995-07-01

    Purpose: A retrospective review analyzed the survival and freedom from relapse of patients with stage IE or IIE primary cutaneous lymphoma (non mycosis fungoides) after treatments with radiation therapy alone (XRT), chemotherapy alone (RX) or combined modality therapy (CMT). Methods and Materials: Fifty two patients with stage IE-IIE cutaneous lymphoma treated at Stanford University Hospital were reviewed. The median age was 57, with a range of 26 to 94 and a male to female ratio of 1.21:1. Patients were staged according to the Ann Arbor System. Pathology was classified according to the Working Formulation. Treatment outcomes were compared using Kaplan-Meier survival curves with a Gehan p-value test. Results: The follow up range was 6 months to 22 years (median 7 years.) Twenty one percent of patients had low grade, 63% had intermediate grade and 15% had high grade lymphoma. The most common histologic subtype was diffuse large cell lymphoma Thirty two patients received radiation alone as initial treatment and sixteen patients received combined modality as initial treatment. Four patients received chemotherapy alone. The only significant prognostic factor for survival was the stage at diagnosis. Patients with stage IE disease had a longer actuarial survival (5-yr=79%, 10-yr=71%), as compared to those with stage IIE (5-yr=49%, 10-yr=33%), (p=0.029). The only significant prognostic factor for freedom from relapse was the initial treatment. Initial combined modality treatment lead to a longer freedom from relapse compared to patients treated with radiation alone (p=0.002), (median 5 years vs. 1.2 years). Despite this, the actuarial overall survival in the combined modality group and the radiation alone group are similar (median survival 7.7 and 8 years). The efficacy of either radiation or chemotherapy as salvage treatment after radiation failure was equivalent and both salvage treatments lead to equally long survival and freedom from second relapse. Conclusion

  12. PRIMARY SCHOOL TEACHER

    CERN Multimedia

    Madeleine Dittus

    2002-01-01

    For January 2003, the A.P.E.G. has an opening for a primary school teacher in the German national language program. The position requires one afternoon of teaching (13:30 till 16:30) every Tuesday at the Collège in Prévessin. The candidate should be a native speaker of German and have some knowledge of French. If you are interested, please send your CV, a copy of your diploma, and a short letter of motivation, until December 9th, to the following address. Madeleine Dittus Présidente A.P.E.G. 5, La vie Destraz 01630 St. Genis-Pouilly (France)

  13. Review of the nuclear liability act

    International Nuclear Information System (INIS)

    1990-01-01

    There has always been concern that nuclear materials have the potential to cause injury and property damage. For this reason, nuclear operators have always been required by national regulatory authorities to exercise special precautions in the operation of their facilities. Federal legislation was drafted in Canada as the Nuclear Liability Act in 1970. The Act ensures that funds are available from all operators of nuclear facilities to provide financial compensation to third parties for injuries or damages suffered as a result of a nuclear incident; at the same time the Act provides protection to the operators by limiting their related liability. The Act also protects persons other than operators. The review of the Act has progressed in stages. The first stage was conducted by the staff of the Atomic Energy Control Board and catalogued previously identified difficulties with the Act. The second stage was a preliminary examination of the Act by an Interdepartmental Working Group. 2 figs

  14. Learning activism, acting with phronesis

    Science.gov (United States)

    Lee, Yew-Jin

    2015-12-01

    The article "Socio-political development of private school children mobilising for disadvantaged others" by Darren Hoeg, Natalie Lemelin, and Lawrence Bencze described a language-learning curriculum that drew on elements of Socioscientific issues and Science, Technology, Society and Environment. Results showed that with a number of enabling factors acting in concert, learning about and engagement in practical action for social justice and equity are possible. An alternative but highly compatible framework is now introduced—phronetic social research—as an action-oriented, wisdom-seeking research stance for the social sciences. By so doing, it is hoped that forms of phronetic social research can gain wider currency among those that promote activism as one of many valued outcomes of an education in science.

  15. Lithuania’s Balancing Act

    Directory of Open Access Journals (Sweden)

    Šlekys Deividas

    2017-12-01

    Full Text Available Since regaining independence in 1990 and creating its regular armed forces, Lithuania has had to do a balancing act. It has had to balance between different approaches of state defence, military structure, collective and national defence. Due to events in Ukraine Lithuania had to reconfigure this balance. The Russian threat forced to emphasize strategy of territorial defence, which altogether required tying up forces and enlarging its numbers by bringing back conscription, substantially increased defence budget, followed by higher tempo and scale in procurement and training. However, Lithuania has managed to maintain its activity and participation in international military operations and political initiatives. Its recent contributions have led to an assumption that its participation in various military missions in the future will not diminish, quite the opposite. Increasing the framework of cooperation in terms of defence and security initiatives will involve Lithuania more deeply and will require further contributions.

  16. Personal Information as Communicative Acts

    DEFF Research Database (Denmark)

    Mai, Jens-Erik

    2016-01-01

    The paper extends previous accounts of informational privacy as a contextual notion. Where previous accounts have focused on interpretations of the privacy context itself as being contextual and open for negotiation and interpretation, this paper extends those analyses and shows that personal...... information itself is in fact best understood as contextual and situational—and as such open for interpretation. The paper reviews the notion of information as it has been applied in informational privacy and philosophy of information, and suggests that personal information ought to be regarded...... as communicative acts. The paper suggests a reconceptualization of informational privacy from having its focus on controlling, limiting, and restricting access to material carriers of information to a focus on a regulation of the use, analysis, and interpretation of personal information....

  17. Pattern of Primary Nocturnal Enuresis in Primary School Children ...

    African Journals Online (AJOL)

    Pattern of Primary Nocturnal Enuresis in Primary School Children (First Grade) in ... The control group consisting of 100 age-matched non-enuretic children ... was insignificantly associated with a positive family history, family size or birth rank.

  18. ACT Reporting Category Interpretation Guide: Version 1.0. ACT Working Paper 2016 (05)

    Science.gov (United States)

    Powers, Sonya; Li, Dongmei; Suh, Hongwook; Harris, Deborah J.

    2016-01-01

    ACT reporting categories and ACT Readiness Ranges are new features added to the ACT score reports starting in fall 2016. For each reporting category, the number correct score, the maximum points possible, the percent correct, and the ACT Readiness Range, along with an indicator of whether the reporting category score falls within the Readiness…

  19. 77 FR 15555 - Freedom of Information Act and Privacy Act Procedures

    Science.gov (United States)

    2012-03-16

    ... Freedom of Information Act and Privacy Act Procedures AGENCY: Special Inspector General for Afghanistan... Freedom of Information Act (FOIA) and the Privacy Act of 1974. These procedures will facilitate public..., Freedom of information, Privacy. Authority and Issuance For the reasons set forth above, SIGAR establishes...

  20. 75 FR 36535 - Freedom of Information Act, Privacy Act of 1974; Implementation

    Science.gov (United States)

    2010-06-28

    ... DEPARTMENT OF THE TREASURY Office of the Secretary 31 CFR Part 1 Freedom of Information Act... Freedom of Information Act (FOIA) and its regulations concerning the Privacy Act of 1974 (Privacy Act). It... correct those errors. List of Subjects in 31 CFR Part 1 Freedom of Information; Privacy. 0 Accordingly...

  1. 13 CFR 107.115 - 1940 Act and 1980 Act Companies.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false 1940 Act and 1980 Act Companies. 107.115 Section 107.115 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS... Companies. A 1940 Act or 1980 Act Company is eligible to apply for an SBIC license, and an existing Licensee...

  2. 75 FR 81205 - Privacy Act: Revision of Privacy Act Systems of Records

    Science.gov (United States)

    2010-12-27

    ... DEPARTMENT OF AGRICULTURE Office of the Secretary Privacy Act: Revision of Privacy Act Systems of Records AGENCY: Office of the Secretary, USDA. ACTION: Notice to Revise Privacy Act Systems of Records... two Privacy Act Systems of Records entitled ``Information on Persons Disqualified from the...

  3. 76 FR 67763 - Privacy Act of 1974; Privacy Act System of Records

    Science.gov (United States)

    2011-11-02

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (11-109)] Privacy Act of 1974; Privacy Act... proposed revisions to an existing Privacy Act system of records. SUMMARY: Pursuant to the provisions of the Privacy Act of 1974 (5 U.S.C. 552a), the National Aeronautics and Space Administration is issuing public...

  4. 76 FR 64114 - Privacy Act of 1974; Privacy Act System of Records

    Science.gov (United States)

    2011-10-17

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (11-093)] Privacy Act of 1974; Privacy Act... proposed revisions to an existing Privacy Act system of records. SUMMARY: Pursuant to the provisions of the Privacy Act of 1974 (5 U.S.C. 552a), the National Aeronautics and Space Administration is issuing public...

  5. 76 FR 64112 - Privacy Act of 1974; Privacy Act System of Records Appendices

    Science.gov (United States)

    2011-10-17

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice (11-091)] Privacy Act of 1974; Privacy Act...: Revisions of NASA Appendices to Privacy Act System of Records. SUMMARY: Notice is hereby given that NASA is... Privacy Act of 1974. This notice publishes those amendments as set forth below under the caption...

  6. 78 FR 40515 - Privacy Act of 1974; Privacy Act System of Records

    Science.gov (United States)

    2013-07-05

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice 13-071] Privacy Act of 1974; Privacy Act System of Records AGENCY: National Aeronautics and Space Administration (NASA). ACTION: Notice of Privacy Act system of records. SUMMARY: Each Federal agency is required by the Privacy Act of 1974 to publish...

  7. 78 FR 77503 - Privacy Act of 1974; Privacy Act System of Records

    Science.gov (United States)

    2013-12-23

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice 13-149] Privacy Act of 1974; Privacy Act... proposed revisions to existing Privacy Act systems of records. SUMMARY: Pursuant to the provisions of the Privacy Act of 1974 (5 U.S.C. 552a), the National Aeronautics and Space Administration is issuing public...

  8. 77 FR 69898 - Privacy Act of 1974; Privacy Act System of Records

    Science.gov (United States)

    2012-11-21

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice 12-100] Privacy Act of 1974; Privacy Act... proposed revisions to an existing Privacy Act system of records. SUMMARY: Pursuant to the provisions of the Privacy Act of 1974 (5 U.S.C. 552a), the National Aeronautics and Space Administration is issuing public...

  9. Acting Antarctica: science on stage

    Science.gov (United States)

    Ciceri, Piera; Tizzoni, Paola; Pierro, Luigia

    2016-04-01

    Key-words: Polar science, Earth science, Theatre, Hands on activities The legendary Antarctic Expedition of sir E. Shackleton and his crew of 27 aboard the Endurance (1914/16) trapped in the Antarctic ice has become the starting point to learn about Polar Science and Climate Change. While the students were involved into this incredible adventure by the astonishing images of the Australian photographer Frank Hurley (who joined the crew), they discovered the world in which this story happened. Students were then involved in hands-on activities and role plays and have become the writers of the play "Uomini a scienza ai confini del mondo". They act the story of Shackelton's expedition and they tell at the same time to the audience about ice pack, ice cores and their role in understanding the past of the climate, physical and geographical characteristic of polar regions, thermal phenomena related to adaptations of polar animals, solar radiation at different latitude, day/night duration. The theater was the place to "stage" some scientific experiments and to explain the current research carried out in polar regions and their importance in climate change studies and to stress some similarities between Antarctica and space. The project was carried out from teachers of science, letters and geography and was born in collaboration with the "Piccolo Teatro di Milano" and the association "Science Under 18" with the support of a professional actor and director and was played for other schools at "EXPO 2015" in Milano (Italy). In our opinion drama activities improve reading comprehension, and both verbal and non-verbal communication skills. To be able to write and to act, students need a deep understanding of contents. Arts, including theatre, are a good key to involve emotionally students. To have an audience different from their own teachers and classmates offers a real task and the opportunity to play and let grow real skills.

  10. Primary iris leiomyoma.

    Science.gov (United States)

    Yeaney, Gabrielle A; Platt, Sean; Singh, Arun D

    Intraocular leiomyomas are uncommon and usually occur in the ciliary body. Primary leiomyoma of the iris is both rare and a difficult diagnosis to make, given melanocytic tumors are more common and may be amelanotic. The somewhat controversial diagnosis of iris leiomyoma requires further confirmation by immunohistochemistry and electron microscopy. Herein, we describe a 58-year-old man with a 2-mm round translucent pink lesion of the iris. The tumor was excised by sector iridectomy. Immunohistochemistry showed positivity for both smooth muscle actin and desmin and negativity for S-100, HMB45, SOX10, MelanA, CD31, CD34, and h-caldesmon. Epstein-Barr virus-associated smooth muscle tumor was excluded by chromogenic in situ hybridization-Epstein-Barr virus-encoded RNA. Ultrastructural analysis showed cytoplasmic myofilaments with focal fusiform densities and micropinocytotic vesicles. Our review of previous literature confirmed the unusual nature of this tumor. Primary iris leiomyoma should be considered in the differential of an amelanotic S-100-immunonegative iris tumor. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Imaging in primary osteosarcomas

    International Nuclear Information System (INIS)

    Davies, A.M.

    1998-01-01

    Osteosarcoma is the most common primary malignant bone tumour with the exception of myeloma. The majority of osteosarcoma cases arise within bone and are called conventional osteosarcoma. Intraosseous variants include telangiectatic, small-cell, low-grade intraosseous and cortical osteosarcoma. Less than 10% of osteosarcomas arise on the surface of bone and are subdivided into periosteal, high-grade surface and parosteal varieties. The imaging features of these subtypes of osteosarcoma are described and the impact on diagnosis highlighted. Using material from over 750 osteosarcomas treated at the author's centre, this article reviews the role of imaging in the management of this condition. Detection still relies principally on the conventional radiograph with bone scintigraphy and MR imaging useful in occult tumours. Establishing the radiological diagnosis depends on careful analysis of the radiographs, with particular attention paid to the nature and extent of bone destruction, periosteal new bone formation and matrix mineralization. The prudent radiologist will be wary of those bone conditions, such as stress fractures and osteomyelitis, which are frequently mistaken for osteosarcoma. Appropriate surgical staging requires MR imaging of the primary tumour to show the bony and soft tissue extent of the lesion and to confirm/exclude skip metastases and local lymph-node involvement. Staging should also include bone scintigraphy to confirm/exclude multiple lesions and chest CT to confirm/exclude pulmonary metastases. Following definitive surgery, imaging is used in the follow-up to monitor potential local recurrence and the development of pulmonary or osseous metastases. (orig.) [de

  12. [Normocalcemic primary hyperparathyroidism].

    Science.gov (United States)

    Spivacow, Francisco R; Sapag Durán, Ana; Zanchetta, María B

    2014-01-01

    This report shows our conclusions on the clinical, biochemical and densitometry characteristics of 35 normocalcemic primary hyperparathyroidism (PHPT) patients. This condition is defined by a high level of intact parathyroid hormone (iPTHI) with persistently normal serum and ionized calcium in the absence of secondary hyperparathyroidism. Our selection consisted of 30 women (90%) and 5 men (10%). The control group of 55 hypercalcemic patients with primary hyperparathyroidism included 51 women (93%) and 4 men (7%). The average age at diagnosis of normocalcemic PHPT was 61.4 ± 11.7 years and 56.4 ± 11.3 years in hypercalcemic PHPT. Besides the expected differences in serum calcium, ionized calcium, phosphorus and 24 h urinary calcium, we found no significant changes in other biochemical variables, and no differences in densitometry evaluations such as the presence of osteopenia or osteoporosis and the number of fractures in the two types of PHPT. But there was a significant difference in the presence of renal lithiasis between normocalcemic PHPT (11.4%) and clasic PHPT (49.1%) p < 0.0005, to some extent associated to the presence of hypercalciuria in classic PHPT. Two of the 35 patients with normocalcemic PHPT became classic hypercalcemic PHPT over a 4 year follow-up period. Our findings support the hypothesis that the normocalcemic PHPT could be an early stage of the classic PHPT, both having similar clinical effects to metabolic renal and bone levels.

  13. Asymptomatic Primary Hyperparathyroidism

    Science.gov (United States)

    Silverberg, Shonni J.; Walker, Marcella D.; Bilezikian, John P.

    2014-01-01

    The clinical profile of primary hyperparathyroidism (PHPT) as it is seen in the United States and most Western countries has evolved significantly over the past half century. The introduction of the multichannel serum autoanalyzer in the 1970s led to the recognition of a cohort of individuals with asymptomatic hypercalcemia, in whom evaluation led to the diagnosis of PHPT. The term “asymptomatic primary hyperparathyroidism” was introduced to describe patients who lack obvious signs and symptoms referable to either excess calcium or parathyroid hormone. Although it was expected that asymptomatic patients would eventually develop classical symptoms of PHPT, observational data suggest that most patients do not evolve over time to become overtly symptomatic. In most parts of the world, the asymptomatic phenotype of PHPT has replaced classical PHPT. This report is a selective review of data on asymptomatic PHPT: its demographic features, presentation and natural history, as well as biochemical, skeletal, neuromuscular, psychological, and cardiovascular manifestations. In addition, we will summarize available information on treatment indications and options for those with asymptomatic disease. PMID:23374736

  14. Structuring payment to medical homes after the affordable care act.

    Science.gov (United States)

    Edwards, Samuel T; Abrams, Melinda K; Baron, Richard J; Berenson, Robert A; Rich, Eugene C; Rosenthal, Gary E; Rosenthal, Meredith B; Landon, Bruce E

    2014-10-01

    The Patient-Centered Medical Home (PCMH) is a leading model of primary care reform, a critical element of which is payment reform for primary care services. With the passage of the Affordable Care Act, the Accountable Care Organization (ACO) has emerged as a model of delivery system reform, and while there is theoretical alignment between the PCMH and ACOs, the discussion of physician payment within each model has remained distinct. Here we compare payment for medical homes with that for accountable care organizations, consider opportunities for integration, and discuss implications for policy makers and payers considering ACO models. The PCMH and ACO are complementary approaches to reformed care delivery: the PCMH ultimately requires strong integration with specialists and hospitals as seen under ACOs, and ACOs likely will require a high functioning primary care system as embodied by the PCMH. Aligning payment incentives within the ACO will be critical to achieving this integration and enhancing the care coordination role of primary care in these settings.

  15. COMMUNITY MEDICINE & PRIMARY HEALTH CARE

    African Journals Online (AJOL)

    Journal of Community Medicine and Primary Health Care. ... Ladoke Akintola University of Technology, PMB 4400, Osogbo, Osun State. ... weak management and poor adherence to the basic infrastructure e.g. primary, secondary and tertiary.

  16. Bezafibrate for primary biliary cirrhosis

    DEFF Research Database (Denmark)

    Rudic, Jelena S; Poropat, Goran; Krstic, Miodrag N

    2012-01-01

    Treatment of primary biliary cirrhosis is complicated. There are studies suggesting that bezafibrate, alone or in combination with ursodeoxycholic acid (UDCA), is effective in the treatment of primary biliary cirrhosis, but no systematic review has summarised the evidence yet....

  17. BR-5 primary circuit decontamination

    International Nuclear Information System (INIS)

    Efimov, I.A.; Nikulin, M.P.; Smirnov-Averin, A.P.; Tymosh, B.S.; Shereshkov, V.S.

    1976-01-01

    Results and methodology of steam-water and acid decontamination of the primary coolant circuit SBR-5 reactor in 1971 are discussed. Regeneration process in a cold trap of the primary coolant circuit is discussed

  18. Fast-acting nuclear reactor control device

    International Nuclear Information System (INIS)

    Kotlyar, O.M.; West, P.B.

    1993-01-01

    A fast-acting nuclear reactor control device is described for controlling a safety control rod within the core of a nuclear reactor, the reactor controlled by a reactor control system, the device comprising: a safety control rod drive shaft and an electromagnetic clutch co-axial with the drive shaft operatively connected to the safety control rod for driving and positioning the safety control rod within or without the reactor core during reactor operation, the safety rod being oriented in a substantially vertical position to allow the rod to fall into the reactor core under the influence of gravity during shutdown of the reactor; the safety control rod drive shaft further operatively connected to a hydraulic pump such that operation of the drive shaft simultaneously drives and positions the safety control rod and operates the hydraulic pump such that a hydraulic fluid is forced into an accumulator, filling the accumulator with oil for the storage and supply of primary potential energy for safety control rod insertion such that the release of potential energy in the accumulator causes hydraulic fluid to flow through the hydraulic pump, converting the hydraulic pump to a hydraulic motor having speed and power capable of full length insertion and high speed driving of the safety control rod into the reactor core; a solenoid valve interposed between the hydraulic pump and the accumulator, said solenoid valve being a normally open valve, actuated to close when the safety control rod is out of the reactor during reactor operation; and further wherein said solenoid opens in response to a signal from the reactor control system calling for shutdown of the reactor and rapid insertion of the safety control rod into the reactor core, such that the opening of the solenoid releases the potential energy in the accumulator to place the safety control rod in a safe shutdown position

  19. Americans with Disabilities Act and the Supreme Court: Implications for Practice.

    Science.gov (United States)

    Katsiyannis, Antonis; Yell, Mitchell L.

    2002-01-01

    This article first reviews the primary requirements of the Americans with Disabilities Act (ADA), then examines four recent U.S. Supreme Court cases that helped clarify who is entitled to its protection. The cases are Murphy vs. United Parcel Services, Inc.; Albertsons, Inc. vs. Kirkingburg (1999); Olmstead, Georgia Department of Human Resources…

  20. The Every Student Succeeds Act: Strengthening the Focus on Educational Leadership

    Science.gov (United States)

    Young, Michelle D.; Winn, Kathleen M.; Reedy, Marcy A.

    2017-01-01

    Purpose: This article offers (a) an overview of the attention federal policy has invested in educational leadership with a primary focus on the Every Student Succeeds Act (ESSA), (b) a summary of the critical role school leaders play in achieving the goals set forth within federal educational policy, and (c) examples of how states are using the…