Analysis and Synthesis of Coupled Microstrip Circuits with More Than Two Coupled Strips

It is shown that the y-parameters for the 2N-port network, N coupled strips form, may be found using almost arbitrary quasi-propagation modes if the relative bandwith of interest is small. Chosing a special set of propagation modes leads to simple expressions for the y-parameters, which are easy to use in an iterative synthesis procedure. The use of quasi-modes also facilitates the calculation of primary parameters (capacitances and phasevelocities). A further advantage is that empirical formulas may be used. Such formulas were developed, which give surprisingly accurate results

Network analysis of the transcriptional pattern of young and old cells of Escherichia coli during lag phase

Background: The aging process of bacteria in stationary phase is halted if cells are subcultured and enter lag phase and it is then followed by cellular division. Network science has been applied to analyse the transcriptional response, during lag phase, of bacterial cells starved previously in stationary phase for 1 day (young cells) and 16 days (old cells). Results: A genome scale network was constructed for E. coli K-12 by connecting genes with operons, transcription and sigma factors, metabolic pathways and cell functional categories. Most of the transcriptional changes were detected immediately upon entering lag phase and were maintained throughout this period. The lag period was longer for older cells and the analysis of the transcriptome revealed different intracellular activity in young and old cells. The number of genes differentially expressed was smaller in old cells (186) than in young cells (467). Relatively, few genes (62) were up- or down-regulated in both cultures. Transcription of genes related to osmotolerance, acid resistance, oxidative stress and adaptation to other stresses was down-regulated in both young and old cells. Regarding carbohydrate metabolism, genes related to the citrate cycle were up-regulated in young cells while old cells up-regulated the Entner Doudoroff and gluconate pathways and down-regulated the pentose phosphate pathway. In both old and young cells, anaerobic respiration and fermentation pathways were down-regulated, but only young cells up-regulated aerobic respiration while there was no evidence of aerobic respiration in old cells.Numerous genes related to DNA maintenance and replication, translation, ribosomal biosynthesis and RNA processing as well as biosynthesis of the cell envelope and flagellum and several components of the chemotaxis signal transduction complex were up-regulated only in young cells. The genes for several transport proteins for iron compounds were up-regulated in both young and old cells. Numerous genes encoding transporters for carbohydrates and organic alcohols and acids were down-regulated in old cells only. Conclusion: Network analysis revealed very different transcriptional activities during the lag period in old and young cells. Rejuvenation seems to take place during exponential growth by replicative dilution of old cellular components

Corporate social responsibility and conflicts of interest in the alcohol and gambling industries: a post-political discourse?

The corporate pursuit of social goals – known as Corporate Social Responsibility or ‘CSR’ – has been subject to critique on a number of grounds. However, a hitherto underexplored potential consequence of CSR has been suggested in a recent paper by C. Garsten and K. Jacobsson (‘Post-Political Regulation: Soft Power and Post-political Visions in Global Governance’ (2013), Critical Sociology 39: 421–37). They suggest that CSR is part of an international trend towards ‘post-political’ governance discourses, where an emphasis on different actors’ common goals obscures conflicts of interest, subverting the open political conflict necessary for a well-functioning democracy. This paper examines whether such post-political discourses – including an outright denial of conflict of interest – can be found within the alcohol and gambling industries, where conflicts of interest are likely to be particularly acute given the addictive nature of the goods/services in question. Based on interviews with CSR professionals in these industries in Italy, the UK, and at EU-level, we do indeed find evidence of a post-political discourse. In these discourses, alcohol/gambling industry staff deny potential conflicts of interest on the basis that any small benefits from sales to a small number of addicts are seen to be outweighed by the reputational damage that addicts cause. Crucially, however, this coexists with another, less post-political discourse, where addictions CSR professionals emphasize ‘common ground’ as a basis for CSR, while accepting some instances of possible conflict of interest. Here interviewees make considerable efforts to differentiate good (sustainable) from bad (short-term) self-interest in order to stress the genuineness of their own actions. We conclude the paper by considering whether CSR embedded within a ‘common ground’ discourse still hides conflicts of interests and subverts democratic debate, or overcomes the problems identified by Garsten and Jacobsson

Enhanced Longevity by Ibuprofen, Conserved in Multiple Species, Occurs in Yeast through Inhibition of Tryptophan Import

The common non-steroidal anti-inflammatory drug ibuprofen has been associated with a reduced risk of some age-related pathologies. However, a general pro-longevity role for ibuprofen and its mechanistic basis remains unclear. Here we show that ibuprofen increased the lifespan of Saccharomyces cerevisiae, Caenorhabditis elegans and Drosophila melanogaster, indicative of conserved eukaryotic longevity effects. Studies in yeast indicate that ibuprofen destabilizes the Tat2p permease and inhibits tryptophan uptake. Loss of Tat2p increased replicative lifespan (RLS), but ibuprofen did not increase RLS when Tat2p was stabilized or in an already long-lived strain background impaired for aromatic amino acid uptake. Concomitant with lifespan extension, ibuprofen moderately reduced cell size at birth, leading to a delay in the G1 phase of the cell cycle. Similar changes in cell cycle progression were evident in a large dataset of replicatively long-lived yeast deletion strains. These results point to fundamental cell cycle signatures linked with longevity, implicate aromatic amino acid import in aging and identify a largely safe drug that extends lifespan across different kingdoms of life.The open access fee for this work was funded through the Texas A&M University Open Access to Knowledge (OAK) Fund