240 resultados para electronic coupling


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NBC's failed attempt to remake the BBC's Coupling generated a significant amount of press coverage in summer 2003. At the core of the debate was a struggle to reconcile an increasingly integrated transatlantic television market with traditional assumptions about culture and its authentic connection to space and place. The interest in the remake not only created a space where certain national differences were played out and performed but also facilitated an equally compelling transatlantic dialogue about creative ownership, appropriation, and a network's responsibility to its audiences. In doing so, the media attention highlighted how television formats are best understood not as innocuous commodities of international trade but as potential sites of articulation, contestation, and community in an increasingly transnational television environment.

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The antenatal paper hand-held record (PHR) has been used extensively in general practice (GP) shared-care management of pregnant women, but recently the antenatal electronic health record (EHR) was introduced. This study aimed to examine the experiences of women and health care providers who use the PHR and the EHR, and find out the relative role of these records in the integration of care. Purposive homogenous samples of women and health care providers were interviewed as users of the PHR in phase 1 and the EHR in phase 2 of the study. Qualitative data were collected via interview with women and GPs and focus groups held with hospital health care providers. Interviews were coded manually and analysed using qualitative content analysis. Fifteen women participated in phase 1 and 12 in phase 2. Seventeen GPs participated in phase 1 and 15 in phase 2. Five focus groups with hospital health care providers were conducted in each phase. Results were categorised into four themes: 1. Record purpose; 2. Perception of the record; 3. Content of the record, and; 4. Sharing information in the record. Both women and health care providers were familiar with the PHR, but identified that some information was missing or not utilised well, and reported underuse of the EHR. The study identified continued widespread use of the PHR and several issues concerning the use of the EHR. An improvement in the strategic implementation of the EHR is suggested as a mechanism to facilitate its wider adoption.

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Bottom emitting organic light emitting diodes (OLEDs) can suffer from lower external quantum efficiencies (EQE) due to inefficient out-coupling of the generated light. Herein, it is demonstrated that the current efficiency and EQE of red, yellow, and blue fluorescent single layer polymer OLEDs is significantly enhanced when a MoOx(5 nm)/Ag(10 nm)/MoOx(40 nm) stack is used as the transparent anode in a top emitting OLED structure. A maximum current efficiency and EQE of 21.2 cd/A and 6.7%, respectively, was achieved for a yellow OLED, while a blue OLED achieved a maximum of 16.5 cd/A and 10.1%, respectively. The increase in light out-coupling from the top-emitting OLEDs led to increase in efficiency by a factor of up to 2.2 relative to the optimised bottom emitting devices, which is the best out-coupling reported using solution processed polymers in a simple architecture and a significant step forward for their use in large area lighting and displays.

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The paper hand-held record (PHR) has been used extensively in general practice (GP) shared care management of pregnant women, and recently, the first Mater Shared Electronic Health Record (MSEHR) was introduced. The aim of this qualitative study was to examine women’s experiences using the records and the contribution of the records to integrate care. At the 36-week antenatal visit in a maternity tertiary centre clinic, women were identified as a user of either the PHR or the MSEHR and organised into Phase 1 and Phase 2 studies respectively. Fifteen women were interviewed in Phase 1 and 12 women in Phase 2. Semi-structured interviews were used for data collection, and analysed using qualitative content analysis. Four main themes were identified: (1) purpose of the record; (2) perceptions of the record; (3) content of the record, and; (4) sharing the record. Findings indicate that the PHR is a well-liked maternity tool. The findings also indicate there is under-usage of the MSEHR due to health-care providers failing to follow up and discuss the option of using the electronic health record option or if a woman has completed the log-in process. This paper adds to an already favourable body of knowledge about the use of the PHR. It is recommended that continued implementation of the MSEHR be undertaken to facilitate its use.

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Palladium (Pd)-catalyzed cross-coupling reactions are among the most important methods in organic synthesis. We report the discovery of highly efficient and green photocatalytic processes by which cross-coupling reactions, including Sonogashira, Stille, Hiyama, Ullmann, and Buchwald–Hartwig reactions, can be driven with visible light at temperatures slightly above room temperature using alloy nanoparticles of gold and Pd on zirconium oxide, thus achieving high yields. The alloy nanoparticles absorb visible light, and their conduction electrons gain energy, which is available at the surface Pd sites. Results of the density functional theory calculations indicate that transfer of the light excited electrons from the nanoparticle surface to the reactant molecules adsorbed on the nanoparticle surface activates the reactants. When the light intensity was increased, a higher reaction rate was observed, because of the increased population of photoexcited electrons. The irradiation wavelength also has an important impact on the reaction rates. Ultraviolet irradiation can drive some reactions with the chlorobenzene substrate, while visible light irradiation failed to, and substantially improve the yields of the reactions with the bromobenzene substrate. The discovery reveals the possibility of using low-energy and -density sources such as sunlight to drive chemical transformations.

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Copper is a low-cost plasmonic metal. Efficient photocatalysts of copper nanoparticles on graphene support are successfully developed for controllably catalyzing the coupling reactions of aromatic nitro compounds to the corresponding azoxy or azo compounds under visible-light irradiation. The coupling of nitrobenzene produces azoxybenzene with a yield of 90 % at 60 °C, but azobenzene with a yield of 96 % at 90 °C. When irradiated with natural sunlight (mean light intensity of 0.044 W cm−2) at about 35 °C, 70 % of the nitrobenzene is converted and 57 % of the product is azobenzene. The electrons of the copper nanoparticles gain the energy of the incident light through a localized surface plasmon resonance effect and photoexcitation of the bound electrons. The excited energetic electrons at the surface of the copper nanoparticles facilitate the cleavage of the NO bonds in the aromatic nitro compounds. Hence, the catalyzed coupling reaction can proceed under light irradiation and moderate conditions. This study provides a green photocatalytic route for the production of azo compounds and highlights a potential application for graphene.

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During their entire lives, people are exposed to the pollutants present in indoor air. Recently, Electronic Nicotine Delivery Systems, mainly known as electronic cigarettes, have been widely commercialized: they deliver particles into the lungs of the users but a “second-hand smoke” has yet to be associated to this indoor source. On the other hand, the naturally-occurring radioactive gas, i.e. radon, represents a significant risk for lung cancer, and the cumulative action of these two agents could be worse than the agents separately would. In order to deepen the interaction between radon progeny and second-hand aerosol from different types of cigarettes, a designed experimental study was carried out by generating aerosol from e-cigarette vaping as well as from second-hand traditional smoke inside a walk-in radon chamber at the National Institute of Ionizing Radiation Metrology (INMRI) of Italy. In this chamber, the radon present in air comes naturally from the floor and ambient conditions are controlled. To characterize the sidestream smoke emitted by cigarettes, condensation particle counters and scanning mobility particle sizer were used. Radon concentration in the air was measured through an Alphaguard ionization chamber, whereas the measurement of radon decay product in the air was performed with the Tracelab BWLM Plus-2S Radon daughter Monitor. It was found an increase of the Potential Alpha-Energy Concentration (PAEC) due to the radon decay products attached to aerosol for higher particle number concentrations. This varied from 7.47 ± 0.34 MeV L−1 to 12.6 ± 0.26 MeV L−1 (69%) for the e-cigarette. In the case of traditional cigarette and at the same radon concentration, the increase was from 14.1 ± 0.43 MeV L−1 to 18.6 ± 0.19 MeV L−1 (31%). The equilibrium factor increases, varying from 23.4% ± 1.11% to 29.5% ± 0.26% and from 30.9% ± 1.0% to 38.1 ± 0.88 for the e-cigarette and traditional cigarette, respectively. These growths still continue for long time after the combustion, by increasing the exposure risk.

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Background The various cell types and their relative numbers in multicellular organisms are controlled by growth factors and related extracellular molecules which affect genetic expression pathways. However, these substances may have both/either inhibitory and/or stimulatory effects on cell division and cell differentiation depending on the cellular environment. It is not known how cells respond to these substances in such an ambiguous way. Many cellular effects have been investigated and reported using cell culture from cancer cell lines in an effort to define normal cellular behaviour using these abnormal cells. A model is offered to explain the harmony of cellular life in multicellular organisms involving interacting extracellular substances. Methods A basic model was proposed based on asymmetric cell division and evidence to support the hypothetical model was accumulated from the literature. In particular, relevant evidence was selected for the Insulin-Like Growth Factor system from the published data, especially from certain cell lines, to support the model. The evidence has been selective in an attempt to provide a picture of normal cellular responses, derived from the cell lines. Results The formation of a pair of coupled cells by asymmetric cell division is an integral part of the model as is the interaction of couplet molecules derived from these cells. Each couplet cell will have a receptor to measure the amount of the couplet molecule produced by the other cell; each cell will be receptor-positive or receptor-negative for the respective receptors. The couplet molecules will form a binary complex whose level is also measured by the cell. The hypothesis is heavily supported by selective collection of circumstantial evidence and by some direct evidence. The basic model can be expanded to other cellular interactions. Conclusions These couplet cells and interacting couplet molecules can be viewed as a mechanism that provides a controlled and balanced division-of-labour between the two progeny cells, and, in turn, their progeny. The presence or absence of a particular receptor for a couplet molecule will define a cell type and the presence or absence of many such receptors will define the cell types of the progeny within cell lineages.

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We report herein highly efficient photocatalysts comprising supported nanoparticles (NPs) of gold (Au) and palladium (Pd) alloys, which utilize visible light to catalyse the Suzuki cross-coupling reactions at ambient temperature. The alloy NPs strongly absorb visible light, energizing the conduction electrons of NPs which produce highly energetic electrons at the surface sites. The surface of the energized NPs activates the substrates and these particles exhibit good activity on a range of typical Suzuki reaction combinations. The photocatalytic efficiencies strongly depend on the Au:Pd ratio of the alloy NPs, irradiation light intensity and wavelength. The results show that the alloy nanoparticles efficiently couple thermal and photonic energy sources to drive Suzuki reactions. Results of the density functional theory (DFT) calculations indicate that transfer of the light-excited electrons from the nanoparticle surface to the reactant molecules adsorbed on the nanoparticle surface activates the reactants. The knowledge acquired in this study may inspire further studies of new efficient photocatalysts and a wide range of organic syntheses driven by sunlight.

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The objective of this study was to compare the short-term respiratory effects due to the inhalation of electronic and conventional tobacco cigarette-generated mainstream aerosols through the measurement of the exhaled nitric oxide (eNO). To this purpose, twenty-five smokers were asked to smoke a conventional cigarette and to vape an electronic cigarette (with and without nicotine), and an electronic cigarette without liquid (control session). Electronic and tobacco cigarette mainstream aerosols were characterized in terms of total particle number concentrations and size distributions. On the basis of the measured total particle number concentrations and size distributions, the average particle doses deposited in alveolar and tracheobronchial regions of the lungs for a single 2-s puff were also estimated considering a subject performing resting (sitting) activity. Total particle number concentrations in the mainstream resulted equal to 3.5 ± 0.4 × 109, 5.1 ± 0.1 × 109, and 3.1 ± 0.6 × 109 part. cm− 3 for electronic cigarettes without nicotine, with nicotine, and for conventional cigarettes, respectively. The corresponding alveolar doses for a resting subject were estimated equal to 3.8 × 1010, 5.2 × 1010 and 2.3 × 1010 particles. The mean eNO variations measured after each smoking/vaping session were equal to 3.2 ppb, 2.7 ppb and 2.8 ppb for electronic cigarettes without nicotine, with nicotine, and for conventional cigarettes, respectively; whereas, negligible eNO changes were measured in the control session. Statistical tests performed on eNO data showed statistically significant differences between smoking/vaping sessions and the control session, thus confirming a similar effect on human airways whatever the cigarette smoked/vaped, the nicotine content, and the particle dose received.

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Public submission # 029 to a Australian federal parliamentary committee considering proposed legislative changes to the Commonwealth's Healthcare Identifiers Act 2010 and the Personally Controlled Electronic Health Records Act 2012.

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The photocatalytic ability of cubic Bi1.5ZnNb1.5O7 (BZN) pyrochlore for the decolorization of an acid orange 7 (AO7) azo dye in aqueous solution under ultraviolet (UV) irradiation has been investigated for the first time. BZN catalyst powders prepared using low temperature sol-gel and higher temperature solid-state methods have been evaluated and their reaction rates have been compared.The experimental band gap energy has been estimated from the optical absorption edge and has been used as reference for theoretical calculations. The electronic band structure of BZN has been investigated using first-principles density functional theory (DFT) calculations for random, completely and partially ordered solid solutions of Zn cations in both the A and B sites of the pyrochlore structure.The nature of the orbitals in the valence band (VB) and the conduction band (CB) has been identified and the theoretical band gap energy has been discussed in terms of the DFT model approximations.

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The equilibrium geometry, electronic structure and energetic stability of Bi nanolines on clean and hydrogenated Si(001) surfaces have been examined by means of ab initio total energy calculations and scanning tunnelling microscopy. For the Bi nanolines on a clean Si surface the two most plausible structural models, the Miki or M model (Miki et al 1999 Phys. Rev. B 59 14868) and the Haiku or H model (Owen et al 2002 Phys. Rev. Lett. 88 226104), have been examined in detail. The results of the total energy calculations support the stability of the H model over the M model, in agreement with previous theoretical results. For Bi nanolines on the hydrogenated Si(001) surface, we find that an atomic configuration derived from the H model is also more stable than an atomic configuration derived from the M model. However, the energetically less stable (M) model exhibits better agreement with experimental measurements for equilibrium geometry. The electronic structures of the H and M models are very similar. Both models exhibit a semiconducting character, with the highest occupied Bi-derived bands lying at ~0.5 eV below the valence band maximum. Simulated and experimental STM images confirm that at a low negative bias the Bi lines exhibit an 'antiwire' property for both structural models.

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Self-organized Bi lines that are only 1.5 nm wide can be grown without kinks or breaks on Si(0 0 1) surfaces to lengths of up to 500 nm. Constant-current topographical images of the lines, obtained with the scanning tunneling microscope, have a striking bias dependence. Although the lines appear darker than the Si terraces at biases below ≈∣1.2∣ V, the contrast reverses at biases above ≈∣1.5∣ V. Between these two ranges the lines and terraces are of comparable brightness. It has been suggested that this bias dependence may be due to the presence of a semiconductor-like energy gap within the line. Using ab initio calculations it is demonstrated that the energy gap is too small to explain the experimentally observed bias dependence. Consequently, at this time, there is no compelling explanation for this phenomenon. An alternative explanation is proposed that arises naturally from calculations of the tunneling current, using the Tersoff–Hamann approximation, and an examination of the electronic structure of the line.

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A Bi 2 × n surface net was grown on the Si(001) surface and studied with inverse photoemission, scanning tunnelling microscopy and ab initio and empirical pseudopotential calculations. The experiments demonstrated that Bi adsorption eliminates the dimer related π1* and π2* surface states, produced by correlated dimer buckling, leaving the bulk bandgap clear of unoccupied surface states. Ab initio calculations support this observation and demonstrate that the surface states derived from the formation of symmetric Bi dimers do not penetrate the fundamental bandgap of bulk Si. Since symmetric Bi dimers are an important structural component of the recently discovered Bi nanolines, that self-organize on Si(001) above the Bi desorption temperature, a connection will be made between our findings and the electronic structure of the nanolines.