2,981 research outputs found

    Chemical Bond and Charge Transfer Dynamics of a Dye-Hierarchical TiO2 Hybrid Interface

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    The adsorption of Zn-Tetra-Phenyl-Porphyrin (ZnTPP) on nanoporous hierarchically organized anatase TiO2 structures, and the properties of the corresponding hybrid interface were studied by synchrotron radiation experiments. The molecular structure, electronic properties and the bonding with nanostructured TiO2 surfaces were analyzed by photoemission (XPS and UPS) and x-ray absorption spectroscopy (XAS). The charge transfer at the interface was investigated by means of valence band resonant photoemission experiments (ResPES) at the C K edge. We show that the charge transfer dynamics between the photo-excited ZnTPP and TiO2 is strongly influenced by the presence of defects on the TiO2 surface. On a stoichiometric anatase nanostructure, ZnTPP bonding occurs primarily via carbon atoms belonging to the molecular phenyl rings and this creates a preferential channel for the charge transfer. This phenomenon is reduced in the case of defective TiO2 surface, where ZnTPP interacts mainly through the molecule macrocycle. Our results represent a surface science study of the dye molecule behavior on a nanoporous TiO2 photoanode relevant to dye-sensitized or hybrid solar cell applications and it shows the importance of the surface oxidation state for the charge transfer proces

    The architectures of translation : a magic carpet-ride through space and time (or, the awkward story of how we dis/placed Krisztina Tóth’s short fiction from Hungarian to English)

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    This interdisciplinary paper unfolds an account of a collaborative translation project, which draws on Ellen Eve Frank’s concept of “literary architecture” to propose a process of “architectural translation”. Our proposal is illustrated by a detailed account of our experiences translating the short fiction of contemporary Hungarian writer, Krisztina Tóth (b. 1967) into English. Staged as a journey through space, time and text, our enquiry frames the process in Barbara Godard’s terms as one of dis/placement, finding resonances with Rosi Braidotti’s nomadic subject and practices of feminist mimesis. Situating Tóth’s fiction in a European feminist literary heritage, we deploy a range of concepts drawn from translation, architecture, literary criticism and feminist philosophy to synthesise a translation strategy which engages the spatial, not only as a metaphor but a methodology for our project. In this account, we propose an architectural methodology as a tool for radical translators, and offer the process of translation as a way of thinking about internal and external spaces in postcolonial contexts

    Cellular and humoral immune responses and protection against schistosomes induced by a radiation-attenuated vaccine in chimpanzees

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    The radiation-attenuated Schistosoma mansoni vaccine is highly effective in rodents and primates but has never been tested in humans, primarily for safety reasons. To strengthen its status as a paradigm for a human recombinant antigen vaccine, we have undertaken a small-scale vaccination and challenge experiment in chimpanzees (Pan troglodytes). Immunological, clinical, and parasitological parameters were measured in three animals after multiple vaccinations, together with three controls, during the acute and chronic stages of challenge infection up to chemotherapeutic cure. Vaccination induced a strong in vitro proliferative response and early gamma interferon production, but type 2 cytokines were dominant by the time of challenge. The controls showed little response to challenge infection before the acute stage of the disease, initiated by egg deposition. In contrast, the responses of vaccinated animals were muted throughout the challenge period. Vaccination also induced parasite-specific immunoglobulin M (IgM) and IgG, which reached high levels at the time of challenge, while in control animals levels did not rise markedly before egg deposition. The protective effects of vaccination were manifested as an amelioration of acute disease and overall morbidity, revealed by differences in gamma-glutamyl transferase level, leukocytosis, eosinophilia, and hematocrit. Moreover, vaccinated chimpanzees had a 46% lower level of circulating cathodic antigen and a 38% reduction in fecal egg output, compared to controls, during the chronic phase of infection

    Possible charge inhomogeneities in the CuO2 planes of YBa2Cu3O6+x (x=0.25, 0.45, 0.65, 0.94) from pulsed neutron diffraction

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    The atomic pair distribution functions (PDF) of four powder samples of YBa2Cu3O6+x (x=0.25, 0.45, 0.65, 0.94) at 15 K have been measured by means of pulsed neutron diffraction. The PDF is modelled using a full-profile fitting approach to yield structural parameters. In contrast to earlier XAFS work we find no evidence of a split apical oxygen site. However, a slightly improved fit over the average crystallographic model results when the planar Cu(2) site is split along the z-direction. This is interpreted in terms of charge inhomogeneities in the CuO2 planes.Comment: 8 pages, 3 figure

    Subclinical hyperthyroidism and dementia: the Sao Paulo Ageing & Health Study (SPAH)

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    <p>Abstract</p> <p>Background</p> <p>Several epidemiologic studies have shown a possible association between thyroid function and cognitive decline. Our aim was to evaluate the association of subclinical hyperthyroidism and dementia in a population sample of older people</p> <p>Methods</p> <p>A cross-sectional study - SĂŁo Paulo Ageing & Health Study (SPAH) - in a population sample of low-income elderly people ≄ 65 years-old to evaluate presence of subclinical thyroid disease as a risk factor for dementia. Thyroid function was assessed using thyrotropic hormone and free-thyroxine as well as routine use of thyroid hormones or antithyroid medications. Cases of dementia were assessed using a harmonized one-phase dementia diagnostic procedure by the "10/66 Dementia Research Group" including Alzheimer's disease and vascular dementia. Logistic regression models were used to test a possible association between subclinical hyperthyroidism and dementia.</p> <p>Results and discussion</p> <p>Prevalence of dementia and of subclinical hyperthyroidism were respectively of 4.4% and 3.0%. After age adjustment, we found an association of subclinical hyperthyroidism and any type of dementia and vascular dementia (Odds Ratio, 4.1, 95% Confidence Interval [95% CI] 1.3-13.1, and 5.3 95% CI, 1.1-26.4; respectively). Analyzing data by gender, we found an association of subclinical hyperthyroidism with dementia and Alzheimer's disease only for men (OR, 8.0; 95% CI, 1.5-43.4; OR, 12.4; 95% CI, 1.2-128.4; respectively). No women with subclinical hypothyroidism presented Alzheimer's disease in the sample.</p> <p>Conclusion</p> <p>The results suggest a consistent association among people with subclinical hyperthyroidism and dementia.</p

    Outline of a sensory-motor perspective on intrinsically moral agents

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    This is the accepted version of the following article: Christian Balkenius, Lola Cañamero, Philip PĂ€rnamets, Birger Johansson, Martin V Butz, and Andreas Olson, ‘Outline of a sensory-motor perspective on intrinsically moral agents’, Adaptive Behaviour, Vol 24(5): 306-319, October 2016, which has been published in final form at DOI: https://doi.org/10.1177/1059712316667203 Published by SAGE ©The Author(s) 2016We propose that moral behaviour of artificial agents could (and should) be intrinsically grounded in their own sensory-motor experiences. Such an ability depends critically on seven types of competencies. First, intrinsic morality should be grounded in the internal values of the robot arising from its physiology and embodiment. Second, the moral principles of robots should develop through their interactions with the environment and with other agents. Third, we claim that the dynamics of moral (or social) emotions closely follows that of other non-social emotions used in valuation and decision making. Fourth, we explain how moral emotions can be learned from the observation of others. Fifth, we argue that to assess social interaction, a robot should be able to learn about and understand responsibility and causation. Sixth, we explain how mechanisms that can learn the consequences of actions are necessary for a robot to make moral decisions. Seventh, we describe how the moral evaluation mechanisms outlined can be extended to situations where a robot should understand the goals of others. Finally, we argue that these competencies lay the foundation for robots that can feel guilt, shame and pride, that have compassion and that know how to assign responsibility and blame.Peer reviewedFinal Accepted Versio

    Education and wealth inequalities in healthy ageing in eight harmonised cohorts in the ATHLOS consortium: a population-based study

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    Background: The rapid growth of the size of the older population is having a substantial effect on health and social care services in many societies across the world. Maintaining health and functioning in older age is a key public health issue but few studies have examined factors associated with inequalities in trajectories of health and functioning across countries. The aim of this study was to investigate trajectories of healthy ageing in older men and women (aged ≄45 years) and the effect of education and wealth on these trajectories. Methods: This population-based study is based on eight longitudinal cohorts from Australia, the USA, Japan, South Korea, Mexico, and Europe harmonised by the EU Ageing Trajectories of Health: Longitudinal Opportunities and Synergies (ATHLOS) consortium. We selected these studies from the repository of 17 ageing studies in the ATHLOS consortium because they reported at least three waves of collected data. We used multilevel modelling to investigate the effect of education and wealth on trajectories of healthy ageing scores, which incorporated 41 items of physical and cognitive functioning with a range between 0 (poor) and 100 (good), after adjustment for age, sex, and cohort study. Findings: We used data from 141 214 participants, with a mean age of 62·9 years (SD 10·1) and an age range of 45–106 years, of whom 76 484 (54·2%) were women. The earliest year of baseline data was 1992 and the most recent last follow-up year was 2015. Education and wealth affected baseline scores of healthy ageing but had little effect on the rate of decrease in healthy ageing score thereafter. Compared with those with primary education or less, participants with tertiary education had higher baseline scores (adjusted difference in score of 10·54 points, 95% CI 10·31–10·77). The adjusted difference in healthy ageing score between lowest and highest quintiles of wealth was 8·98 points (95% CI 8·74–9·22). Among the eight cohorts, the strongest inequality gradient for both education and wealth was found in the Health Retirement Study from the USA. Interpretation: The apparent difference in baseline healthy ageing scores between those with high versus low education levels and wealth suggests that cumulative disadvantage due to low education and wealth might have largely deteriorated health conditions in early life stages, leading to persistent differences throughout older age, but no further increase in ageing disparity after age 70 years. Future research should adopt a lifecourse approach to investigate mechanisms of health inequalities across education and wealth in different societies. Funding: European Union Horizon 2020 Research and Innovation Programme.The ATHLOS project was funded by the European Union Horizon 2020 Research and Innovation Programme (grant number 635316). This study was supported by the 5-year ATHLOS projec

    Histone Acetylation-Mediated Regulation of the Hippo Pathway

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    The Hippo pathway is a signaling cascade recently found to play a key role in tumorigenesis therefore understanding the mechanisms that regulate it should open new opportunities for cancer treatment. Available data indicate that this pathway is controlled by signals from cell-cell junctions however the potential role of nuclear regulation has not yet been described. Here we set out to verify this possibility and define putative mechanism(s) by which it might occur. By using a luciferase reporter of the Hippo pathway, we measured the effects of different nuclear targeting drugs and found that chromatin-modifying agents, and to a lesser extent certain DNA damaging drugs, strongly induced activity of the reporter. This effect was not mediated by upstream core components (i.e. Mst, Lats) of the Hippo pathway, but through enhanced levels of the Hippo transducer TAZ. Investigation of the underlying mechanism led to the finding that cancer cell exposure to histone deacetylase inhibitors induced secretion of growth factors and cytokines, which in turn activate Akt and inhibit the GSK3 beta associated protein degradation complex in drug-affected as well as in their neighboring cells. Consequently, expression of EMT genes, cell migration and resistance to therapy were induced. These processes were suppressed by using pyrvinium, a recently described small molecule activator of the GSK 3 beta associated degradation complex. Overall, these findings shed light on a previously unrecognized phenomenon by which certain anti-cancer agents may paradoxically promote tumor progression by facilitating stabilization of the Hippo transducer TAZ and inducing cancer cell migration and resistance to therapy. Pharmacological targeting of the GSK3 beta associated degradation complex may thus represent a unique approach to treat cancer. © 2013 Basu et al

    Combined In Silico, In Vivo, and In Vitro Studies Shed Insights into the Acute Inflammatory Response in Middle-Aged Mice

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    We combined in silico, in vivo, and in vitro studies to gain insights into age-dependent changes in acute inflammation in response to bacterial endotoxin (LPS). Time-course cytokine, chemokine, and NO2-/NO3- data from "middle-aged" (6-8 months old) C57BL/6 mice were used to re-parameterize a mechanistic mathematical model of acute inflammation originally calibrated for "young" (2-3 months old) mice. These studies suggested that macrophages from middle-aged mice are more susceptible to cell death, as well as producing higher levels of pro-inflammatory cytokines, vs. macrophages from young mice. In support of the in silico-derived hypotheses, resident peritoneal cells from endotoxemic middle-aged mice exhibited reduced viability and produced elevated levels of TNF-α, IL-6, IL-10, and KC/CXCL1 as compared to cells from young mice. Our studies demonstrate the utility of a combined in silico, in vivo, and in vitro approach to the study of acute inflammation in shock states, and suggest hypotheses with regard to the changes in the cytokine milieu that accompany aging. © 2013 Namas et al
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