Targeted design leads to tunable photoluminescence from perylene dicarboxdiimide-poly(oxyalkylene)/siloxane hybrids for luminescent solar concentrators

The chain length and branching of the organic backbone of poly(oxyalkylene)/siloxane ureasils can be used to control the placement and orientation of a covalently-grafted perylene, leading to tunable photoluminescence.</p

Cork suberin as an additive in offset lithographic printing inks

Suberin oligomers, isolated from cork (Quercus suber L.), were used as additives in ‘Waterless’ and vegetable-oil ink formulations, in the range of 2–10% w/w. The rheological behaviour of the suberin oligomers as well as of the inks, with and without suberin, were investigated as a function of temperature. It was shown that the addition of suberin induces a decrease of viscosity of both inks. The tack of pristine inks, suberin oligomers and their mixtures were determined at different temperatures: the variation of this parameter as a function of time provided information about the drying kinetics of these formulations. The tack of the ‘Waterless’ ink was found to increase with the introduction of suberin, whereas that of vegetable-oil based counterparts decreased. All the trends observed were interpreted in terms of the differences in composition between the two types of inks. Preliminary printing tests were carried out with the various suberin-containing inks.info:eu-repo/semantics/publishedVersio

In situ probing of surface hydrides on hydrogenated amorphous silicon using attenuated total reflection infrared spectroscopy

An in situ method based on attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) is presented for detecting surface silicon hydrides on plasma deposited hydrogenated amorphous silicon (a-Si:H) films and for determining their surface concentrations. Surface silicon hydrides are desorbed by exposing the a-Si:H films to low energy ions from a low density Ar plasma and by comparing the infrared spectrum before and after this low energy ion bombardment, the absorptions by surface hydrides can sensitively be separated from absorptions by bulk hydrides incorporated into the film. An experimental comparison with other methods that utilize isotope exchange of the surface hydrogen with deuterium showed good agreement and the advantages and disadvantages of the different methods are discussed. Furthermore, the determination of the composition of the surface hydrogen bondings on the basis of the literature data on hydrogenated crystalline silicon surfaces is presented, and quantification of the hydrogen surface coverage is discusse

Physics–Dynamics Coupling in weather, climate and Earth system models: Challenges and recent progress

This is the final version. Available from American Meteorological Society via the DOI in this record.Numerical weather, climate, or Earth system models involve the coupling of components. At a broad level, these components can be classified as the resolved fluid dynamics, unresolved fluid dynamical aspects (i.e., those represented by physical parameterizations such as subgrid-scale mixing), and nonfluid dynamical aspects such as radiation and microphysical processes. Typically, each component is developed, at least initially, independently. Once development is mature, the components are coupled to deliver a model of the required complexity. The implementation of the coupling can have a significant impact on the model. As the error associated with each component decreases, the errors introduced by the coupling will eventually dominate. Hence, any improvement in one of the components is unlikely to improve the performance of the overall system. The challenges associated with combining the components to create a coherent model are here termed physics–dynamics coupling. The issue goes beyond the coupling between the parameterizations and the resolved fluid dynamics. This paper highlights recent progress and some of the current challenges. It focuses on three objectives: to illustrate the phenomenology of the coupling problem with references to examples in the literature, to show how the problem can be analyzed, and to create awareness of the issue across the disciplines and specializations. The topics addressed are different ways of advancing full models in time, approaches to understanding the role of the coupling and evaluation of approaches, coupling ocean and atmosphere models, thermodynamic compatibility between model components, and emerging issues such as those that arise as model resolutions increase and/or models use variable resolutions.Natural Environment Research Council (NERC)National Science FoundationDepartment of Energy Office of Biological and Environmental ResearchPacific Northwest National Laboratory (PNNL)DOE Office of Scienc

ECONOMIC INTEGRATION FOR DEVELOPMENT IN EASTERN AND SOUTHERN AFRICA: ASSESSMENT AND PROSPECTS

Summary Eastern and Southern Africa has a long history of efforts to achieve operational economic integration and a complex set of overlapping institutional frames. The gains from successful cooperation are agreed ? the basic issues turn on how to attain them. In this context the experiences of the two key actors, PTA (Preferential Trade Area) and SADC (Southern African Development Community), offer insights into the strengths and weaknesses of a broad, secretariat?led trade barrier reducing organization and a narrower (geographically), key sector production coordination, country?led one (SADC). The divergences ? as well as history ? have hampered attempts to coordinate or to merge them and their responses to the opportunities and challenges posed by the re?entry of South Africa into Africa. The latter raises rather more complex issues (and ones less threatening ? or promising in some respects ? to its Eastern and Southern African region potential partners) than is sometimes supposed. Resumé efforts pour d'obtenir l'intégration économique et de rendre celle?ci opérationnelle dans le contexte d'une série complexe de cadres institutionnels parfois superposés. Les gains résultant des réussites dans la coopération ne sont pas contestés: les questions fondamentales tournent autour des moyens d'y parvenir. Dans ce contexte l'expérience de deux acteurs principaux (la PTA – Preferential Trade Area ou Zone commerciale privilégiée et la SADC – Southern African Development Community ou Communauté de développement de l'Afrique australe) offrent des aperçus quant aux avantages et désavantages de l'existence d'une organisation de grande envergure et fondée sur secrétariat, consacrée à la réduction des barrières douannières, et d'une autre organisation, cette fois limitée en termes de sa superficie géographique et menée par des pays, qui cherche à coordiner la production dans les secteurs clef: la SADC. Leurs divergences, et l'histoire même, ont servi d'entrave aux efforts de les coordiner ou de les faire fusionner, surtout en ce qui concerne les nouvelles possibilités et le challenge même de la réintégration de l'Afrique du Sud dans la grande Afrique. Cette réintégration soulève des questions un peu plus complexes (et moins menaçantes) et aussi, moins promettrices sous certains jours pour ses éventuels partenaires dans les régions orientales et australes de l'Afrique) qu'on ne le supposerait parfois. Resumen El Africa oriental y el Africa austral tienen un largo historial de esfuerzos para alcanzar la integración económica operacional y un complejo grupo de estructuras institucionales superpuestas. Los beneficios de una cooperación exitosa no están en discusión ? el punto básico es cómo obtenerlos. En este contexto las experiencias de dos actores clave, (la PTA?Preferential Trade Area o Zona de Comercio Privilegiado, y la SADC ? Southern Africa Development Community o Comunidad para el Desarrollo de Africa Austral), ofrecen interesantes revelaciones sobre los puntos fuertes y débiles de una amplia y burocrática barrera comercial que reduce la organización, y la coordinación de la producción en sectores clave de un área geográfica más reducida, de orientación nacional. Las divergenias ? así como la historia ? han estorbado intentos de combinar o coordinar estos dos aspectos y sus respuestas a las oportunidades o desafíos que presenta el reingreso de Sudafrica al Africa. Esto último plantea más asuntos complejos de los que a veces se suponen (y menos amenazantes ? más prometedores en alugunos aspectos) para sus socios comerciales en potencia en Africa oriental y Africa del sur

Parent satisfaction with the Loire Infant Follow-up Team (LIFT) premature and at-risk infant network in the Pays-de-la-Loire area (France)

BACKGROUND: The Loire Infant Follow-up Team (LIFT) is a network for caring for premature infants whose gestational age is 34 WA or less and at-risk neonates in the Pays-de-la-Loire area in France. The network aims to screen for clinical anomalies early and to propose adapted care. Trained physicians follow the included children in a standardized manner at 3, 6, 9, 12, and 18 months and 2 years, with a specific examination by psychologists at 2 years. The aim of the study was to assess the satisfaction of the parents of the children followed.METHODS: To evaluate parent satisfaction, a questionnaire from the Consumer Satisfaction Survey (CSS) in its French version was sent to parents whose infants were 2 years old, stratifying on the presence of an anomaly. The questioner had 39 items, with 8 specific items on the network and 31 from the CSS. The questionnaire was mailed twice in September 2006. RESULTS: Out of 300 questionnaires mailed, 269 were returned (rate 89.7 %). The questionnaire was assessed using principal component analysis with 2 dimensions for the 30 items common to all children, one of which covered empathy with physicians and the other with the consulting psychologists at 2 years. The validity was good (Cronbach coefficient, 0.91). The answers to overall questions such as "We are satisfied with the care in the network" scored 16.1±0.7/20, with 90 % "totally agree" or "moderately agree" responses. The "The care is perfect" scored 14.6±0.7/20 with 78 % agreeing with the statement. The total score for 30 general questions was 14.6±3.1 (median, 14.9). The total score was lower for infants with anomalies: 13.7±3.3 versus 14.9±2.9 (P&lt;0.01). The answers with a low score (&lt;10) were given by 22 parents (8.2 %). There was no significant relation between the total score or the satisfaction score and neonatal events. CONCLUSION: A postal survey is helpful to know the views of parents on the follow-up of their infants. This good level of satisfaction seems to stem from the parents feeling they belong to the network, the quality of the relationships with personnel, and the doctors\u27 empathy, as well as the number of contacts between parents and the network coordinator

Piston-driven numerical wave tank based on WENO solver of well-balanced shallow water equations

A numerical wave tank equipped with a piston type wave-maker is presented for long-duration simulations of long waves in shallow water. Both wave maker and tank are modelled using the nonlinear shallow water equations, with motions of the numerical piston paddle accomplished via a linear mapping technique. Three approaches are used to increase computational efficiency and accuracy. First, the model satisfies the exact conservation property (C-property), a stepping stone towards properly balancing each term in the governing equation. Second, a high-order weighted essentially non-oscillatory (WENO) method is used to reduce accumulation of truncation error. Third, a cut-off algorithm is implemented to handle contaminated digits arising from round-off error. If not treated, such errors could prevent a numerical scheme from satisfying the exact C-property in long-duration simulations. Extensive numerical tests are performed to examine the well-balanced property, high order accuracy, and shock-capturing ability of the present scheme. Correct implementation of the wave paddle generator is verified by comparing numerical predictions against analytical solutions of sinusoidal, solitary, and cnoidal waves. In all cases, the model gives satisfactory results for small-amplitude, low frequency waves. Error analysis is used to investigate model limitations and derive a user criterion for long wave generation by the model