198 research outputs found

    Quasiparticle interfacial level alignment of highly hybridized frontier levels: H2_2O on TiO2_2(110)

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    Knowledge of the frontier levels' alignment prior to photo-irradiation is necessary to achieve a complete quantitative description of H2_2O photocatalysis on TiO2_2(110). Although H2_2O on rutile TiO2_2(110) has been thoroughly studied both experimentally and theoretically, a quantitative value for the energy of the highest H2_2O occupied levels is still lacking. For experiment, this is due to the H2_2O levels being obscured by hybridization with TiO2_2(110) levels in the difference spectra obtained via ultraviolet photoemission spectroscopy (UPS). For theory, this is due to inherent difficulties in properly describing many-body effects at the H2_2O-TiO2_2(110) interface. Using the projected density of states (DOS) from state-of-the-art quasiparticle (QP) G0W0G_0W_0, we disentangle the adsorbate and surface contributions to the complex UPS spectra of H2_2O on TiO2_2(110). We perform this separation as a function of H2_2O coverage and dissociation on stoichiometric and reduced surfaces. Due to hybridization with the TiO2_2(110) surface, the H2_2O 3a1_1 and 1b1_1 levels are broadened into several peaks between 5 and 1 eV below the TiO2_2(110) valence band maximum (VBM). These peaks have both intermolecular and interfacial bonding and antibonding character. We find the highest occupied levels of H2_2O adsorbed intact and dissociated on stoichiometric TiO2_2(110) are 1.1 and 0.9 eV below the VBM. We also find a similar energy of 1.1 eV for the highest occupied levels of H2_2O when adsorbed dissociatively on a bridging O vacancy of the reduced surface. In both cases, these energies are significantly higher (by 0.6 to 2.6 eV) than those estimated from UPS difference spectra, which are inconclusive in this energy region. Finally, we apply self-consistent QPGWGW (scQPGWGW1) to obtain the ionization potential of the H2_2O-TiO2_2(110) interface.Comment: 12 pages, 12 figures, 1 tabl

    Measuring care of the elderly: psychometric testing and modification of the Time in Care instrument for measurement of care needs in nursing homes

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    <p>Abstract</p> <p>Background</p> <p>Aging entails not only a decrease in the ability to be active, but also a trend toward increased dependence to sustain basic life functions. An important aspect for appropriately elucidating the individual's care needs is the ability to measure them both simply and reliably. Since 2006 a new version of the Time in Care needs (TIC-n) instrument (19-item version) has been explored and used in one additional municipality with the same structure as the one described in an earlier study.</p> <p>Methods</p> <p>The TIC-n assessment was conducted on a total of 1282 care recipients. Factor analysis (principal component) was applied to explore the construct validity of the TIC-n. Cronbach's alpha was calculated to test reliability and for each of the items remaining in the instrument after factor analysis, an inter-rater comparison was carried out on all recipients in both municipalities. Independently of each other, a weighted Kappa (K<sub>w</sub>) was calculated. Results. The mean of each weighted Kappa (K<sub>w</sub>) for the dimensions in the two municipalities was 0.75 and 0.76, respectively. Factor analysis showed that all 19 items had a factor loading of ≥ 0.40. Three factors (General Care, Medical Care and Cognitive Care) were created.</p> <p>Conclusion</p> <p>The TIC-n instrument has now been tested for validity and reliability in two municipalities with satisfactory results. However, TIC-n can not yet be used as a golden standard, but it can be recommended for use of measurement of individual care needs in municipal elderly care.</p

    Distributional impacts of cash allowances for children: A microsimulation analysis for Russia and Europe

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    This article analyses programmes of cash allowances for children and compares their effectiveness in combating child poverty in Russia and four European Union (EU) countries representing alternative family policy models – Sweden, Germany, Belgium and the United Kingdom. Using microsimulation models, this article estimates the potential gains if the Russian system were re-designed along the policy parameters of these countries and vice versa. The results confirm that the poverty impact of the programme design is smaller than that of the level of spending. Other conditions being equal, the best distributional outcomes for children are achieved by applying the mix of universal and means-tested child benefits, such as those employed by the United Kingdom and Belgium. At the same time, the Russian design of child allowances does not appear to be less effective in terms of its impact on child poverty when transferred to European countries in place of their current arrangements

    Use of selective serotonin reuptake inhibitors and risk of re-operation due to post-surgical bleeding in breast cancer patients: a Danish population-based cohort study

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    <p>Abstract</p> <p>Background</p> <p>Selective serotonin reuptake inhibitors (SSRI) decrease platelet-function, which suggests that SSRI use may increase the risk of post-surgical bleeding. Few studies have investigated this potential association.</p> <p>Methods</p> <p>We conducted a population-based study of the risk of re-operation due to post-surgical bleeding within two weeks of primary surgery among Danish women with primary breast cancer. Patients were categorised according to their use of SSRI: never users, current users (SSRI prescription within 30 days of initial breast cancer surgery), and former users (SSRI prescription more than 30 days before initial breast cancer surgery). We calculated the risk of re-operation due to post-surgical bleeding within 14 days of initial surgery, and the relative risk (RR) of re-operation comparing SSRI users with never users of SSRI adjusting for potential confounders.</p> <p>Results</p> <p>389 of 14,464 women (2.7%) were re-operated. 1592 (11%) had a history of SSRI use. Risk of re-operation was 2.6% among never users, 7.0% among current SSRI users, and 2.7% among former users. Current users thus had an increased risk of re-operation due to post-operative bleeding (adjusted relative risk = 2.3; 95% confidence interval (CI) = 1.4, 3.9) compared with never users. There was no increased risk of re-operation associated with former use of SSRI (RR = 0.93, 95% CI = 0.66, 1.3).</p> <p>Conclusions</p> <p>Current use of SSRI is associated with an increased risk of re-operation due to bleeding after surgery for breast cancer.</p

    Negotiating care in the context of Finnish and Italian elder care policies

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    Negotiation is an integral part of all elder care, which by definition involves a relation between at least two people. In this article we analyse negotiations concerning elder care in the context of Finnish and Italian elder care policies. At the macro level negotiations on elder care are shaped by elder care policies and at the micro level by individual skills and resources. Our focus is on the negotiations on eligibility that take place when elders attempt to access care. The data consist of qualitative interviews with Finnish and Italian elders in need of care. The analysis of individual experiences of care negotiations reflects the implementation of elder care policies. The results indicate that the most negotiated eligibility criteria when seeking access to elder care are need, money and social relations. These criteria are negotiated when seeking eligibility to different sources of care: informal care, grey market, market-based, non-profit and public services. In Italy, negotiation is particularly crucial when accessing grey market care. Cash as the main Italian elder care policy tool tends to enhance the role of and need for negotiation. In Finland, a greater part of elder care is provided by the public sector and therefore the process of negotiation is more standardized than in Italy

    Synthesis and characterization of triangulene

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    Triangulene, the smallest triplet-ground-state polybenzenoid (also known as Clar's hydrocarbon), has been an enigmatic molecule ever since its existence was first hypothesized1. Despite containing an even number of carbons (22, in six fused benzene rings), it is not possible to draw Kekulé-style resonant structures for the whole molecule: any attempt results in two unpaired valence electrons2. Synthesis and characterization of unsubstituted triangulene has not been achieved because of its extreme reactivity1, although the addition of substituents has allowed the stabilization and synthesis of the triangulene core3, 4 and verification of the triplet ground state via electron paramagnetic resonance measurements5. Here we show the on-surface generation of unsubstituted triangulene that consists of six fused benzene rings. The tip of a combined scanning tunnelling and atomic force microscope (STM/AFM) was used to dehydrogenate precursor molecules. STM measurements in combination with density functional theory (DFT) calculations confirmed that triangulene keeps its free-molecule properties on the surface, whereas AFM measurements resolved its planar, threefold symmetric molecular structure. The unique topology of such non-Kekulé hydrocarbons results in open-shell π-conjugated graphene fragments6 that give rise to high-spin ground states, potentially useful in organic spintronic devices7, 8. Our generation method renders manifold experiments possible to investigate triangulene and related open-shell fragments at the single-molecule level
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