Conversion of silica diatom frustules to BaTiO3, SrTiO3, and Nb2O5

Diatom frustules were used as bio-templates to synthesize functional ceramics via solid-gas displacement reactions. Silica based frustules were exposed to TiF4 at 3300C to form TiOF2 which is later converted to TiO2 (anatase) by heat treatment in air at 6000C. The TiO2 frustules were then exposed to Ba(OH)2 at 1200C or Sr(OH)2 at 1600C to form BaTiO3 or SrTiO3 respectively. Chemical composition, structure, and morphology of the converted frustules were studied by XRD, TEM, SEM, EDS. In both cases near complete conversion was achieved while retaining the morphology of the original silica frustules. Conversion of diatom frustules to Nb2O5 by solid-gas displacement reaction was also studied. Silica based frustules were exposed to NbF5 vapors at 3300C which formed niobium oxy-fluoride ( NbO2F) intermediate. Oxygenation of the intermediate was attempted in oxygen atmosphere at high temperatures which resulted in formation of Nb3O7F along with various off-stoichiometric niobium oxides. Conversion to Nb2O5 and its derivatives accompanied by evolution of NbOF3 which compromised the shape of the original frustules

Conversion of silica diatom frustules to BaTiO₃, SrTiO₃, and Nb₂O₅

Diatom frustules were used as bio-templates to synthesize functional ceramics via solid-gas displacement reactions. Silica based frustules were exposed to TiF₄ at 330°C to form TiOF₂ which is later converted to TiO₂ (anatase) by heat treatment in air at 600°C. The TiO₂ frustules were then exposed to Ba(OH)₂ at 120°C or Sr(OH)₂ at 160°C to form BaTiO₃ or SrTiO₃ respectively. Chemical composition, structure, and morphology of the converted frustules were studied by XRD, TEM, SEM, EDS. In both cases near complete conversion was achieved while retaining the morphology of the original silica frustules. Conversion of diatom frustules to Nb₂O₅ by solid-gas displacement reaction was also studied. Silica based frustules were exposed to NbF₅ vapors at 330°C which formed niobium oxy-fluoride (NbO₂F) intermediate. Oxygenation of the intermediate was attempted in oxygen atmosphere at high temperatures which resulted in formation of Nb₃O--F along with various off-stoichiometric niobium oxides. Conversion to Nb₂O₅ and its derivatives accompanied by evolution of NbOF₃ which compromised the shape of the original frustules

On choosing and bounding probability metrics

When studying convergence of measures, an important issue is the choice of probability metric. In this review, we provide a summary and some new results concerning bounds among ten important probability metrics/distances that are used by statisticians and probabilists. We focus on these metrics because they are either well-known, commonly used, or admit practical bounding techniques. We summarize these relationships in a handy reference diagram, and also give examples to show how rates of convergence can depend on the metric chosen.Comment: To appear, International Statistical Review. Related work at http://www.math.hmc.edu/~su/papers.htm

Parenting interventions for male young offenders: a review of the evidence on what works

Approximately one in four incarcerated male young offenders in the UK is an actual or expectant father. This paper reviews evidence on the effectiveness of parenting interventions for male young offenders. We conducted systematic searches across 20 databases and consulted experts. Twelve relevant evaluations were identified: 10 from the UK, of programmes for incarcerated young offenders, and two from the US, of programmes for young parolees. None used experimental methods or included a comparison group. They suggest that participants like the courses, find them useful, and the interventions may improve knowledge about, and attitudes to, parenting. Future interventions should incorporate elements of promising parenting interventions with young fathers in the community, for example, and/or with older incarcerated parents. Young offender fathers have specific developmental, rehabilitative, and contextual needs. Future evaluations should collect longer-term behavioural parent and child outcome data and should use comparison groups and, ideally, randomization

Improving the design process for factories:modelling human performance variation

Theprocess of manufacturing system design frequently includes modeling, and usually, this means applying a technique such as discrete event simulation (DES). However, the computer tools currently available to apply this technique enable only a superficial representation of the people that operate within the systems. This is a serious limitation because the performance of people remains central to the competitiveness of many manufacturing enterprises. Therefore, this paper explores the use of probability density functions to represent the variation of worker activity times within DES models

Finding music in music data : a summary of the DaCaRyH Project

The international research project, “Data science for the study of calypso-rhythm through history” (DaCaRyH), involved a collaboration between ethnomusicologists, computer scientists, and a composer. The primary aim of DaCaRyH was to explore how ethnomusicology could inform data science, and vice versa. Its secondary aim focused on creative applications of the results. This article summarises the results of the project, and more broadly discusses the benefits and challenges in such interdisciplinary research. It concludes with suggestions for reducing the barriers to similar work

Network-Based Elucidation of Human Disease Similarities Reveals Common Functional Modules Enriched for Pluripotent Drug Targets

Current work in elucidating relationships between diseases has largely been based on pre-existing knowledge of disease genes. Consequently, these studies are limited in their discovery of new and unknown disease relationships. We present the first quantitative framework to compare and contrast diseases by an integrated analysis of disease-related mRNA expression data and the human protein interaction network. We identified 4,620 functional modules in the human protein network and provided a quantitative metric to record their responses in 54 diseases leading to 138 significant similarities between diseases. Fourteen of the significant disease correlations also shared common drugs, supporting the hypothesis that similar diseases can be treated by the same drugs, allowing us to make predictions for new uses of existing drugs. Finally, we also identified 59 modules that were dysregulated in at least half of the diseases, representing a common disease-state “signature”. These modules were significantly enriched for genes that are known to be drug targets. Interestingly, drugs known to target these genes/proteins are already known to treat significantly more diseases than drugs targeting other genes/proteins, highlighting the importance of these core modules as prime therapeutic opportunities

The commodification and exploitation of fresh water: Property, human rights and green criminology

In recent years, both developing and industrialised societies have experienced riots and civil unrest over the corporate exploitation of fresh water. Water conflicts increase as water scarcity rises and the unsustainable use of fresh water will continue to have profound implications for sustainable development and the realisation of human rights. Rather than states adopting more costly water conservation strategies or implementing efficient water technologies, corporations are exploiting natural resources in what has been described as the “privatization of water”. By using legal doctrines, states and corporations construct fresh water sources as something that can be owned or leased. For some regions, the privatization of water has enabled corporations and corrupt states to exploit a fundamental human right. Arguing that such matters are of relevance to criminology, which should be concerned with fundamental environmental and human rights, this article adopts a green criminological perspective and draws upon Treadmill of Production theory