35 research outputs found

    Strategies to control the spectral properties of Au-Ni thin films

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    Gold and nickel have quite different dielectric functions. Here we use a combination of calculation and sample manufacture to assess two strategies by which thin films of these elements can be produced with a controlled range of far-field optical properties. In the first approach, control can be achieved by manipulating the density of states of metastable solid solutions, which in turn controls the dielectric function. In the second approach the optical properties of the films are controlled by varying the geometry of stacks fabricated from the constituent elements. We show that the two approaches can produce equivalent results so both are viable options in practice. Modeling is used to reveal how the structure controls the optical properties and to map out the possible color gamut. Predictions are tested with thin film samples fabricated by magnetron sputtering. © 2013 Elsevier B.V

    A Battle Lost? Report on Two Centuries of Invasion and Management of Lantana camara L. in Australia, India and South Africa

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    Recent discussion on invasive species has invigorated the debate on strategies to manage these species. Lantana camara L., a shrub native to the American tropics, has become one of the worst weeds in recorded history. In Australia, India and South Africa, Lantana has become very widespread occupying millions of hectares of land. Here, we examine historical records to reconstruct invasion and management of Lantana over two centuries and ask: Can we fight the spread of invasive species or do we need to develop strategies for their adaptive management? We carried out extensive research of historical records constituting over 75% of records on invasion and management of this species in the three countries. The records indicate that governments in Australia, India and South Africa have taken aggressive measures to eradicate Lantana over the last two centuries, but these efforts have been largely unsuccessful. We found that despite control measures, the invasion trajectory of Lantana has continued upwards and that post-war land-use change might have been a possible trigger for this spread. A large majority of studies on invasive species address timescales of less than one year; and even fewer address timescales of >10 years. An understanding of species invasions over long time-scales is of paramount importance. While archival records may give only a partial picture of the spread and management of invasive species, in the absence of any other long-term dataset on the ecology of Lantana, our study provides an important insight into its invasion, spread and management over two centuries and across three continents. While the established paradigm is to expend available resources on attempting to eradicate invasive species, our findings suggest that in the future, conservationists will need to develop strategies for their adaptive management rather than fighting a losing battle

    Functional epigenomics approach to identify methylated candidate tumour suppressor genes in renal cell carcinoma

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    Promoter region hypermethylation and transcriptional silencing is a frequent cause of tumour suppressor gene (TSG) inactivation in many human cancers. Previously, to identify candidate epigenetically inactivated TSGs in renal cell carcinoma (RCC), we monitored changes in gene expression in four RCC cell lines after treatment with the demethylating agent 5-azacytidine. This enabled us to identify HAI-2/SPINT2 as a novel epigenetically inactivated candidate RCC TSG. To identify further candidate TSGs, we undertook bioinformatic and molecular genetic evaluation of a further 60 genes differentially expressed after demethylation. In addition to HAI-2/SPINT2, four genes (PLAU, CDH1, IGFB3 and MT1G) had previously been shown to undergo promoter methylation in RCC. After bioinformatic prioritisation, expression and/or methylation analysis of RCC cell lines±primary tumours was performed for 34 genes. KRT19 and CXCL16 were methylated in RCC cell lines and primary RCC; however, 22 genes were differentially expressed after demethylation but did not show primary tumour-specific methylation (methylated in normal tissue (n=1); methylated only in RCC cell lines (n=9) and not methylated in RCC cell lines (n=12)). Re-expression of CXCL16 reduced growth of an RCC cell line in vitro. In a summary, a functional epigenomic analysis of four RCC cell lines using microarrays representing 11 000 human genes yielded both known and novel candidate TSGs epigenetically inactivated in RCC, suggesting that this is valid strategy for the identification of novel TSGs and biomarkers

    Albert Pierrepoint and the cultural persona of the twentieth-century hangman

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    Albert Pierrepoint was Britain’s most famous 20th-century hangman. This article utilises diverse sources in order to chart his public representation, or cultural persona, as hangman from his rise to prominence in the mid-1940s to his portrayal in the biopic Pierrepoint(2005). It argues that Pierrepoint exercised agency in shaping this persona through publishing his autobiography and engagement with the media, although there were also representations that he did not influence. In particular, it explores three iterations of his cultural persona – the Professional Hangman, the Reformed Hangman and the Haunted Hangman. Each of these built on and reworked historical antecedents and also communicated wider understandings and contested meanings in relation to capital punishment. As a hangman who remained in the public eye after the death penalty in Britain was abolished, Pierrepoint was an important, authentic link to the practice of execution and a symbolic figure in debates over reintroduction. In the 21st century, he was portrayed as a victim of the ‘secondary trauma’ of the death penalty, which resonated with worldwide campaigns for abolition

    Molecular mechanisms of cell death: recommendations of the Nomenclature Committee on Cell Death 2018.

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    Over the past decade, the Nomenclature Committee on Cell Death (NCCD) has formulated guidelines for the definition and interpretation of cell death from morphological, biochemical, and functional perspectives. Since the field continues to expand and novel mechanisms that orchestrate multiple cell death pathways are unveiled, we propose an updated classification of cell death subroutines focusing on mechanistic and essential (as opposed to correlative and dispensable) aspects of the process. As we provide molecularly oriented definitions of terms including intrinsic apoptosis, extrinsic apoptosis, mitochondrial permeability transition (MPT)-driven necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic cell death, NETotic cell death, lysosome-dependent cell death, autophagy-dependent cell death, immunogenic cell death, cellular senescence, and mitotic catastrophe, we discuss the utility of neologisms that refer to highly specialized instances of these processes. The mission of the NCCD is to provide a widely accepted nomenclature on cell death in support of the continued development of the field

    Changes in singing performance and fMRI activation following right temporal lobe surgery

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    The fulltext of this publication will be made publicly available after relevant embargo periods have lapsed and associated copyright clearances obtained.INTRODUCTION: This study arose in the context of having to estimate risk to the musical abilities of a trained singer (patient A.M.) recommended for right anterior temporal lobectomy (RATL) to ameliorate medically intractable seizures. To date there has been no systematic investigation of reorganisation of musical functions in the presence of epileptogenic lesions, although it is well established that RATL can impair pitch processing in nonmusicians. METHODS: Using fMRI, we compared the network activated by covert singing with lyrics in A.M. before and after surgery, while taking language activation and singing expertise into consideration. Before surgery, A.M. showed lower pitch accuracy of singing relative to individuals of similar experience (experts), thus we compared her to 12 healthy controls matched for singing pitch accuracy. RESULTS: We found atypical organisation of A.M.'s singing network before surgery in the presence of a malformation of cortical development, including partial activation of the singing network of pitch-matched controls, and diffuse activation along the midline spreading laterally into association cortex, typical of generalised cortical hyperexcitability in intractable epilepsy. After tailored RATL, A.M. showed striking behavioural and neuroimaging changes, including significant improvement in pitch accuracy of singing relative to controls (p = .026) and the subjective experience of being a more technically proficient singer. This was accompanied by a significant reduction in cortical activation (p < .05, corrected), with a more focal, expert-like pattern of singing activation emerging, including decreased involvement of frontal language regions. These changes were largely specific to singing, with A.M. showing language activation and performance similar to controls. CONCLUSIONS: This case provides evidence for selective disruption of the singing network that reorganised after successful resection of an epileptogenic lesion and likely occurred through decoupling of the singing and language networks
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