522 research outputs found

    PIM-1 membranes containing POSS - graphene oxide for CO2 separation

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    PIM-1 mixed matrix membranes (MMMs) were fabricated with polyhedral oligomeric silsesquioxane (POSS) and graphene oxide (GO) functionalized with POSS (GO-POSS), and tested for CO2/N2 (single gas) and CO2/CH4 (1:1, v:v gas mixture). The CO2 permeability of the best performing fresh MMM (containing 0.05 wt% GO-POSS) was ~ 12000 Barrer, which is 69% higher than that of the neat PIM-1 membrane, with about the same selectivity (CO2/CH4 selectivity ~ 12 and CO2/N2 selectivity ~ 20). In both cases, the gas separation data surpass the 2008 Robeson upper bound. In addition to the initial CO2 permeability enhancement, the use of GO-POSS is an efficient strategy to slow down physical aging. The MMM at a filler loading of 0.75 wt% showed less than half of the reduction in CO2 permeability than the neat PIM-1 membrane 160 days after preparation (26% for the MMM vs 58% for the purely polymeric one). © 2022 The Author(s

    Born Digital: Early Career Researchers Shaping Digital Art History

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    In October 2017, the authors co-organised an international conference for early career researchers (ECRs) entitled ‘Digital Art History: Practice and Potential’ (#DAHPP). This ambitious event, held between The Paul Mellon Centre for Studies in British Art and The Courtauld Institute of Art, brought together ECRs working independently and at major institutions in Austria, China, France, Portugal, America, and the United Kingdom, all of whom use digital technologies to support and disseminate research. Through a lens focused by Diane M Zorich’s assertion that ECRs are more likely to “think through technology”, this article demonstrates how emerging scholars are engaging with digital technology in conjunction with established art-historical methods and theories in an integrated practice. Drawing on digital projects presented at #DAHPP, we reflect on the intellectual, logistical and methodological focal points arising from the event, discussed in four sections: the centrality of digital technology to ECRs’ research practices and the need to generate discussion around this in light of the professional challenges we face; the growing prevalence of digital re-constructions as both research tool and vehicle for communicating with a broad audience; digital methods for dealing with data, how this can disrupt bias within conventional art-historical study; and how we address questions of veracity and authenticity

    Spatial scales of variance in abundance of intertidal species: effects of region, dispersal mode, and trophic level

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    Determination of the pattern of variation in population abundance among spatial scales offers much insight into the potential regulating factors. Here we offer a method of quantifying spatial variance on a range of scales derived by sampling of irregularly spaced sites along complex coastlines. We use it to determine whether the nature of spatial variance depends on the trophic level or the mode of dispersal of the species involved and the role of the complexity of the underlying habitat. A least-cost distance model was used to determine distances by sea between all pairs of sites. Ordination of this distance matrix using multidimensional scaling allowed estimation of variance components with hierarchical ANOVA at nested spatial scales using spatial windows. By repeatedly moving these spatial windows and using a second set of spatial scales, average variance scale functions were derived for 50+ species in the UK rocky intertidal. Variance spectra for most species were well described by the inverse power law (1/f?) for noise spectra, with values for the exponent ranging from 0 to 1.1. At higher trophic levels (herbivores and carnivores), those species with planktonic dispersal had significantly higher ? values, indicating greater large- than small-scale variability, as did those on simpler coastlines (southwestern England and Wales vs. western Scotland). Average abundance and proportional incidence of species had the strongest influence on ? values, with those of intermediate abundance and incidence having much greater large-scale variance (? ? 0.5) than rare or ubiquitous species (? ? 0)

    International Whaling Commission–Southern Ocean GLOBEC/CCAMLR collaboration. Scientific Committee document SC/55/E10, International Whaling Commission, May-June 2003, Berlin, Germany

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    Collaboration between the International Whaling Commission, and national programs conducting multidisciplinary ecosystem research in the Antarctic under Southern Ocean Global Ecosystem Dynamics (SO GLOBEC) program and the Commission for the Convention on Antarctic Marine Living Resources (CCAMLR) occurred during five research cruises between April 2002 and April 2003. Visual survey, passive acoustic and tissue biopsy work was conducted by IWC observers and collaborating passive acoustics scientists. Reported here are the preliminary results from these cruises: mapped distribution patterns of cetaceans from visual survey sighting data; individual photo identification records; species identification and positions of animals recorded on sonobuoys; and descriptions of environmental conditions observed or recorded as part of the multidisciplinary effort

    Individual, unit and vocal clan level identity cues in sperm whale codas

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    Fieldwork was supported by Discovery and Equipment grants to H.W. from the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Whale and Dolphin Conservation Society. S.G. and L.R. were supported by the Marine Alliance for Science and Technology for Scotland (MASTs) pooling initiative and their support is gratefully acknowledged. MASTs is funded by the Scottish Funding Council (grant reference HR09011) and contributing institutions. S.G. was also supported by an NSERC Postgraduate Scholarship (PGS-M), an NSERC Canadian Graduate Scholarship (CGS-D), the Izaak Killam Memorial Scholarship, the Patrick F. Lett Fund, the Dalhousie’s Presidents Award, and an FNU fellowship for the Danish Council for Independent Research from the Ministry of Higher Education and Science supplemented by a Sapere Aude Research Talent Award.The ‘social complexity hypothesis’ suggests that complex social structure is a driver of diversity in animal communication systems. Sperm whales have a hierarchically structured society in which the largest affiliative structures, the vocal clans, are marked on ocean-basin scales by culturally transmitted dialects of acoustic signals known as ‘codas’. We examined variation in coda repertoires among both individual whales and social units—the basic element of sperm whale society—using data from nine Caribbean social units across six years. Codas were assigned to individuals using photo-identification and acoustic size measurement, and we calculated similarity between repertoires using both continuous and categorical methods. We identified 21 coda types. Two of those (‘1+1+3’ and ‘5R1’) made up 65% of the codas recorded, were shared across all units and have dominated repertoires in this population for at least 30 years. Individuals appear to differ in the way they produce ‘5R1’ but not ‘1+1+3’ coda. Units use distinct 4-click coda types which contribute to making unit repertoires distinctive. Our results support the social complexity hypothesis in a marine species as different patterns of variation between coda types suggest divergent functions, perhaps representing selection for identity signals at several levels of social structure.Publisher PDFPeer reviewe

    Vertical flotation of particles in a paramagnetic fluid

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    Hirota et al. [6] found that the magneto-Archimedes force could be used to levitate biological materials at different heights in pressurized oxygen, providing the possibility to separate them. However the magnetic levitation of mineral particles has not been widely explored. With this in mind some preliminary experiments were performed by levitating pure mineral materials in a paramagnetic solution manganese (II) chloride. Besides the report of levitation heights of various mineral particles in manganese (II) chloride solution, the lines obtained from the basic formula provided by previous researchers were compared with experimental data. The act of cryogenic paramagnetic fluid in the magneto-Archimedes levitation was also demonstrated. The obtained results are compared with the same particle levitation heights in manganese (II) chloride solution

    Effectiveness of a care bundle to reduce surgical site infections in patients having open colorectal surgery

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    Introduction In 2010 a care bundle was introduced by the Department of Health (DH) to reduce surgical site infections (SSIs) in England. To date, use of the care bundle has not been evaluated despite incorporating interventions with resource implications. The aim of this study was to evaluate the DH SSI care bundle in open colorectal surgery. Methods A prospective cohort design was used at two teaching hospitals in England. The baseline group consisted of 127 consecutive patients having colorectal surgery during a 6-month period while the intervention group comprised 166 patients in the subsequent 6 months. SSI and care bundle compliance data were collected using dedicated surveillance staff. Results Just under a quarter (24%) of the patients in the baseline group developed a SSI compared with just over a quarter (28%) in the care bundle group (p>0.05). However, compliance rates with individual interventions, both before and after the implementation of the bundle, were similar. Interestingly, in only 19% of cases was there compliance with the total care bundle. The single intervention that showed an associated reduction in SSI was preoperative warming (p=0.032). Conclusions The DH care bundle did not reduce SSIs after open colorectal surgery. Despite this, it is not possible to state that the bundle is ineffective as compliance rates before and after bundle implementation were similar. All studies evaluating the effectiveness of care bundles must include data for compliance with interventions both before and after implementation of the care bundle; poor compliance may be one of the reasons for the lower than expected reduction of SSIs

    Individual and Situational Factors Related to Young Women’s Likelihood of Confronting Sexism in Their Everyday Lives

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    Factors related to young women’s reported likelihood of confronting sexism were investigated. Participants were 338 U.S. female undergraduates (M = 19 years) attending a California university. They were asked to complete questionnaire measures and to write a personal narrative about an experience with sexism. Approximately half (46%) the women reported confronting the perpetrator. Individual factors (prior experience with sexism, feminist identification, collective action) and situational factors (familiarity and status of perpetrator, type of sexism) were tested as predictors in a logistic regression. Women were less likely to report confronting sexism if (1) they did not identify as feminists, (2) the perpetrator was unfamiliar or high-status/familiar (vs. familiar/equal-status), or (3) the type of sexism involved unwanted sexual attention (vs. sexist comments)

    Particle separation by horizontal deflection in paramagnetic fluid

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    This paper describes the horizontal deflection behaviour of the streams of particles in paramagnetic fluids under a high-gradient superconducting magnetic field, which is the continued work on the exploration of particle magneto-Archimedes levitation. Based on the previous work on the horizontal deflection of a single particle, a glass box and collector had been designed to observe the movement of particle group in paramagnetic fluids. To get the exact separation efficiency, the method of "sink-float" involved the high density fluid polytungstate (dense medium separation) and MLA (Mineral Liberation Analyser) was performed. It was found that the particles were deflected and settled at certain positions on the container floor due to the combined forces of gravity and magneto-Archimedes forces as well as a lateral buoyancy (displacement) force. Mineral particles with different densities and susceptibilities could be deflected to different positions, thus producing groups of similar types of particles. The work described here, although in its infancy, could form the basis of new approach of separating particles based on a combination of susceptibility and density
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