402 research outputs found

    More to Mutton than Meets the Eye

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    A 64-year-old Mexican fisherman with a history of syphilis is diagnosed with panuveitis of the right eye after presenting with unilateral blurry vision, redness, and pain. A PPD was 35X30mm, and chest X-ray suggested tuberculosis. The patient’s pain and vision improved with 4-drug anti-tuberculous therapy, topical steroids, and cycloplegic eye drops

    Enlarged symmetry algebras of spin chains, loop models, and S-matrices

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    The symmetry algebras of certain families of quantum spin chains are considered in detail. The simplest examples possess m states per site (m\geq2), with nearest-neighbor interactions with U(m) symmetry, under which the sites transform alternately along the chain in the fundamental m and its conjugate representation \bar{m}. We find that these spin chains, even with {\em arbitrary} coefficients of these interactions, have a symmetry algebra A_m much larger than U(m), which implies that the energy eigenstates fall into sectors that for open chains (i.e., free boundary conditions) can be labeled by j=0, 1, >..., L, for the 2L-site chain, such that the degeneracies of all eigenvalues in the jth sector are generically the same and increase rapidly with j. For large j, these degeneracies are much larger than those that would be expected from the U(m) symmetry alone. The enlarged symmetry algebra A_m(2L) consists of operators that commute in this space of states with the Temperley-Lieb algebra that is generated by the set of nearest-neighbor interaction terms; A_m(2L) is not a Yangian. There are similar results for supersymmetric chains with gl(m+n|n) symmetry of nearest-neighbor interactions, and a richer representation structure for closed chains (i.e., periodic boundary conditions). The symmetries also apply to the loop models that can be obtained from the spin chains in a spacetime or transfer matrix picture. In the loop language, the symmetries arise because the loops cannot cross. We further define tensor products of representations (for the open chains) by joining chains end to end. The fusion rules for decomposing the tensor product of representations labeled j_1 and j_2 take the same form as the Clebsch-Gordan series for SU(2). This and other structures turn the symmetry algebra \cA_m into a ribbon Hopf algebra, and we show that this is ``Morita equivalent'' to the quantum group U_q(sl_2) for m=q+q^{-1}. The open-chain results are extended to the cases |m|< 2 for which the algebras are no longer semisimple; these possess continuum limits that are critical (conformal) field theories, or massive perturbations thereof. Such models, for open and closed boundary conditions, arise in connection with disordered fermions, percolation, and polymers (self-avoiding walks), and certain non-linear sigma models, all in two dimensions. A product operation is defined in a related way for the Temperley-Lieb representations also, and the fusion rules for this are related to those for A_m or U_q(sl_2) representations; this is useful for the continuum limits also, as we discuss in a companion paper

    Reproductive Failure in UK Harbour Porpoises Phocoena phocoena : Legacy of Pollutant Exposure?

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    This research was supported by a Marie Curie International Outgoing Fellowship within the Seventh European Community Framework Programme (Project Cetacean-stressors, PIOF-GA-2010-276145 to PDJ and SM). Additional funding was provided through the Agreement on the Conservation of Small Cetaceans of the Baltic, North East Atlantic, Irish and North Seas (ASCOBANS) (Grants SSFA/2008 and SSFA / ASCOBANS / 2010 / 5 to SM). Analysis of Scottish reproductive and teeth samples was funded by the EC-funded BIOCET project (BIOaccumulation of persistent organic pollutants in small CETaceans in European waters: transport pathways and impact on reproduction, grant EVK3-2000-00027 to GJP), and Marine Scotland (GJP). Samples examined in this research were collected under the collaborative Cetacean Strandings Investigation Programme (http://ukstrandings.org/), which is funded by the Department for Environment, Food and Rural Affairs (Defra) and the UK’s Devolved Administrations in Scotland and Wales (http://sciencesearch.defra.gov.uk/Defaul​t.aspx?Menu=Menu&Module=More&Location=No​ne&Completed=0&ProjectID=15331) (grants to PDJ, RD). UK Defra also funded the chemical analysis under a service-level agreement with the Centre for Environment, Fisheries and Aquaculture Science (grants to RJL, JB). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

    Fisheries interactions of Delphinus delphis in the north-east Atlantic with an emphasis on Galicia, north-west Spain.

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    Bycatch from interactions with fisherie s remains the biggest global threat to marine mammals. Galicia, north - west Spain, is one of the world’s main fishing regions and a high level of cetacean - fisheries interactions has been reported from on - board observers, interviews with fisheries stakeholde rs and analysis of stranded and by - caught carcasses. Delphinus delphis is the most abundant cetacean in the area and since 1990 necropsies of over 1800 stranded and by - caught Delphinus have been conducted. Life history data (age, maturity, and pregnancy ra te data) from stranded and by - caught cetaceans can be used to construct life tables and to estimate overall mortality and fisheries mortality rates. Age and maturity were determined from stranded and by - caught Delphinus between 1990 and 2009. Males and fem ales reach sexual maturity at 8.5 and 7.5 years of age, respectively, and no temporal difference in age at sexual maturity was observed. Results indicate 13% annual mortality in the Delphinus delphis north - east Atlantic population and necropsy data suggest s that 60% of mortality (i.e. 7.2% annual mortality) is attributable to fisheries interactions, predominantly from pair trawls and gillnets. By - caught Delphinus were found to die significantly younger than non - by - caught animals (p=<0.001) although no sex - r elated difference in bycatch rate was observed (p=0.051). The estimated annual mortality due to fisheries interactions greatly exceeds the 2% limit set by ASCOBANS and the IWC and high bycatch rates are also reported for other countries e.g. the UK, France and Portugal. Although Delphinus delphis in the north - east Atlantic is one continuous population, the high level of bycatch occurring in parts of the range is most likely unsustainable and will be discussed. There is a need to carry out on - board monitorin g, notably in the north - west Iberian Peninsula (Galicia and Portugal), to incorporate cetacean bycatch into fisheries advice and, above all, to start introducing mitigation measures

    Employee share ownership, psychological ownership, and work attitudes and behaviours: A phenomenological analysis

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    This is the peer reviewed version of the following article: MCCONVILLE, D., ARNOLD, J. and SMITH, A., 2016. Employee share ownership, psychological ownership, and work attitudes and behaviours: A phenomenological analysis. Journal of Occupational and Organizational Psychology, 89 (3), pp. 634-655, which has been published in final form at http://dx.doi.org/10.1111/joop.12146. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.This study uses qualitative data to explore how employees perceive the relationships between employee share ownership (ESO) scheme participation, their attitudes and behaviours at work, and their feelings of psychological ownership (PO). We contribute to two areas of (largely quantitative) research literature. First, we advance understanding of PO by examining participants' explanations of how they feel their sense of PO is affected by participating in a company ESO scheme. Second, we examine the role of PO in employees' explanations of the attitudinal and behavioural changes they feel they have experienced as a consequence of participating in an ESO scheme. To explore the subjective meaning of ESO participation and its PO impact, 37 semi-structured interviews were conducted in nine companies with participants in three tax-advantaged ESO schemes in the United Kingdom: SIP, SAYE, and EMI. Data were coded and analysed using thematic analysis (Braun & Clarke, 2006). Participants perceived little effect of ESO schemes on PO or on the organizational features anticipated to give rise to these feelings. In turn, PO was found to play little or no part in employees' explanations of how share schemes had, or did not have, an attitudinal or behavioural impact. Practitioner points: Interviewees reflected on their experiences of joining employee share ownership (ESO) schemes, holding options, exercising options, and owning shares in the company. There was very little evidence that employees felt that any of these stages of ESO participation had any noticeable effect on their feelings of psychological ownership (PO). Other factors seemed to satisfy PO routes before, and possibly better than, ESO. Psychological ownership played little or no part in employees' explanations of how the ESO scheme impacted upon their attitudes or behaviours. The findings contrast with the conventional wisdom, that participating in an ESO scheme inevitably causes employees to feel a sense of ownership over the company. We find that ESO had very little to do with ownership in the minds of employees. Instead, it was much more about investment. ESO was not seen as a mechanism for employees to have a sense of ownership over the company and employees did not appear to regard ESO as providing experiences of the three ownership rights, or the routes to PO which parallel these

    Inter-species differences in polychlorinated biphenyls patterns from five sympatric species of odontocetes : Can PCBs be used as tracers of feeding ecology?

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    The authors gratefully acknowledge the assistance of volunteers from the Galician (CEMMA) and Portuguese (SPVS) stranding networks. The authors would like to thank R. Gallois and C. Trichet for their participation on total lipid content analysis. P. Méndez-Fernandez was supported during the research period through a PhD grant from the Fundação do Ministério de Ciência e Tecnologia de Portugal and ANIMATE project (SFRH/BD/36766/2007) and through a Science Without Borders (CSF) young talent postdoctoral grant of the Brazilian government. G. J. Pierce acknowledges support from the EU ANIMATE project (MEXC-CT-2006-042337), University of Aveiro and Caixa Geral de Depósitos (Portugal).Peer reviewedPostprin

    Multi-scale investigation of uranium attenuation by arsenic at an abandoned uranium mine, South Terras

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    Detailed mineralogical analysis of soils from the UK’s historical key uranium mine, South Terras, was performed to elucidate the mechanisms of uranium degradation and migration in the 86 years since abandonment. Soils were sampled from the surface (0 – 2 cm) and near-surface (25 cm) in two distinct areas of ore processing activities. Bulk soil analysis revealed the presence of high concentrations of uranium (<1690 ppm), arsenic (1830 ppm) and beryllium (~250 ppm), suggesting pedogenic weathering of the country rock and ore extraction processes to be the mechanisms of uranium ore degradation. Micro-focus XRF analysis indicated the association of uranium with arsenic, phosphate and copper; µ-XRD data confirmed the presence of the uranyl-arsenate minerals metazeunerite (Cu(UO2)2(AsO4)2·8H2O) and metatorbernite (Cu(UO2)2(PO4)2·8H2O) to be ubiquitous. Our data are consistent with the solid solution of these two uranyl-mica minerals, not previously observed at uranium-contaminated sites. Crystallites of uranyl-mica minerals were observed to coat particles of jarosite and muscovite, suggesting that the mobility of uranium from degraded ores is attenuated by co-precipitation with arsenic and phosphate, which was not previously considered at this site

    Patterns and trends in cetacean strandings on the Galician coast and their relationship with oceanography and fishing effort

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    Poster.-- ICES 2014 Annual Science Conference, 15- 19 September 2014, A CoruñaStrandings provide valuable information on the presence and relative abundance of cetaceans in an area. The spatial, inter-annual and seasonal variation in the number of strandings may reflect the variability in cetacean abundance. However, this signal can be masked by other factors which are responsible both for the mortality of the dolphins and the probability that they reach the shore once they are dead. We analysed the time series of cetacean strandings in Galicia (NW Spain), available since 1990, with the aim of determining the trends and variability of strandings. We found that seasonal and inter-annual variation in the number of strandings is highly correlated with the oceanographic conditions most prevalent in each period. Moreover, a more detailed analysis of these effects should be carried out, and the use of further applicable indices (fishing effort rather than landings) may improve the explained part of the models, thus allowing us to disentangle oceanographic effects and to obtain relative seasonal and annual abundancesN
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