139 research outputs found

    An investigation into the effects of solvent content on the image quality and stability of ink jet digital prints under varied storage conditions

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    Increasing numbers of galleries, museums and archives are including ink jet printed materials into their collections, and therefore displays. There is evidence that the instability of these prints is such that images can suffer deterioration in print quality or in extreme cases, a loss of information over an extended period of time. This is shorter than the period typically required for perceptible deterioration to occur in many other paper-based artworks. The image stability of prints is affected by a number of factors some of which have already been studied. However the role played by the ink solvent in the loss of image quality has yet to be explored. This paper will outline research being undertaken to investigate the effects of solvent content which may increase/promote the loss in image quality of the hard copy prints when stored or displayed under a range of temperature and humidity conditions

    The Antarctic ice core chronology (AICC2012): an optimized multi-parameter and multi-site dating approach for the last 120 thousand years

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    The deep polar ice cores provide reference records commonly employed in global correlation of past climate events. However, temporal divergences reaching up to several thousand years (ka) exist between ice cores over the last climatic cycle. In this context, we are hereby introducing the Antarctic Ice Core Chronology 2012 (AICC2012), a new and coherent timescale developed for four Antarctic ice cores, namely Vostok, EPICA Dome C (EDC), EPICA Dronning Maud Land (EDML) and Talos Dome (TALDICE), alongside the Greenlandic NGRIP record. The AICC2012 timescale has been constructed using the Bayesian tool Datice (Lemieux-Dudon et al., 2010) that combines glaciological inputs and data constraints, including a wide range of relative and absolute gas and ice stratigraphic markers. We focus here on the last 120 ka, whereas the companion paper by Bazin et al. (2013) focuses on the interval 120–800 ka. Compared to previous timescales, AICC2012 presents an improved timing for the last glacial inception, respecting the glaciological constraints of all analyzed records. Moreover, with the addition of numerous new stratigraphic markers and improved calculation of the lock-in depth (LID) based on δ15N data employed as the Datice background scenario, the AICC2012 presents a slightly improved timing for the bipolar sequence of events over Marine Isotope Stage 3 associated with the seesaw mechanism, with maximum differences of about 600 yr with respect to the previous Datice-derived chronology of Lemieux-Dudon et al. (2010), hereafter denoted LD2010. Our improved scenario confirms the regional differences for the millennial scale variability over the last glacial period: while the EDC isotopic record (events of triangular shape) displays peaks roughly at the same time as the NGRIP abrupt isotopic increases, the EDML isotopic record (events characterized by broader peaks or even extended periods of high isotope values) reached the isotopic maximum several centuries before. It is expected that the future contribution of both other long ice core records and other types of chronological constraints to the Datice tool will lead to further refinements in the ice core chronologies beyond the AICC2012 chronology. For the time being however, we recommend that AICC2012 be used as the preferred chronology for the Vostok, EDC, EDML and TALDICE ice core records, both over the last glacial cycle (this study), and beyond (following Bazin et al., 2013). The ages for NGRIP in AICC2012 are virtually identical to those of GICC05 for the last 60.2 ka, whereas the ages beyond are independent of those in GICC05modelext (as in the construction of AICC2012, the GICC05modelext was included only via the background scenarios and not as age markers). As such, where issues of phasing between Antarctic records included in AICC2012 and NGRIP are involved, the NGRIP ages in AICC2012 should therefore be taken to avoid introducing false offsets. However for issues involving only Greenland ice cores, there is not yet a strong basis to recommend superseding GICC05modelext as the recommended age scale for Greenland ice cores

    Cork suberin as an additive in offset lithographic printing inks

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    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

    A single-component photorheological fluid with light-responsive viscosity.

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    Viscoelastic fluids whose rheological properties are tunable with light have the potential to deliver significant impact in fields relying on a change in flow behavior, such as in-use tuning of combined efficient heat-transfer and drag-reduction agents, microfluidic flow and controlled encapsulation and release. However, simple, single-component systems must be developed to allow integration with these applications. Here, we report a single-component viscoelastic fluid, capable of a dramatic light-sensitive rheological response, from a neutral azobenzene photosurfactant, 4-hexyl-4'butyloxymonotetraethylene glycol (C6AzoOC4E4) in water. From cryo-transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS) and rheology measurements, we observe that the photosurfactant forms an entangled network of wormlike micelles in water, with a high viscosity (28 Pa s) and viscoelastic behaviour. UV irradiation of the surfactant solution creates a less dense micellar network, with some vesicle formation. As a result, the solution viscosity is reduced by four orders of magnitude (to 1.2 × 10-3 Pa s). This process is reversible and the high and low viscosity states can be cycled several times, through alternating UV and blue light irradiation

    PPARgamma in complex with an antagonist and inverse agonist: a tumble and trap mechanism of the activation helix

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    Peroxisome proliferator activated receptor γ (PPARγ) is a nuclear receptor and target for antidiabetics that increase insulin sensitivity. Owing to the side effects of PPARγ full agonists, research has recently focused on non-activating ligands of PPARγ, which increase insulin sensitivity with decreased side effects. Here, we present the crystal structures of inverse agonist SR10171 and a chemically related antagonist SR11023 bound to the PPARγ ligand-binding domain, revealing an allosteric switch in the activation helix, helix 12 (H12), forming an antagonist conformation in the receptor. H12 interacts with the antagonists to become fixed in an alternative location. Native mass spectrometry indicates that this prevents contacts with coactivator peptides and allows binding of corepressor peptides. Antagonists of related nuclear receptors act to sterically prevent the active configuration of H12, whereas these antagonists of PPARγ alternatively trap H12 in an inactive configuration, which we have termed the tumble and trap mechanism.Rebecca L. Frkic, Andrew C. Marshall, Anne-Laure Blayo, Tara L. Pukala, Theodore M. Kamenecka, Patrick R. Griffin, and John B. Brunin

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

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    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

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

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    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<0.01). The answers with a low score (<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
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