Multicolor bipartite Ramsey number of double stars

For positive integers $n, m$, the double star $S(n,m)$ is the graph consisting of the disjoint union of two stars $K_{1,n}$ and $K_{1,m}$ together with an edge joining their centers. Finding monochromatic copies of double stars in edge-colored complete bipartite graphs has attracted much attention. The $k$-color bipartite Ramsey number of $S(n,m)$, denoted by $r_{bip}(S(n,m);k)$, is the smallest integer $N$ such that, in any $k$-coloring of the edges of the complete bipartite graph $K_{N,N}$, there is a monochromatic copy of $S(n,m)$. The study of bipartite Ramsey numbers was initiated in the early 1970s by Faudree and Schelp and, independently, by Gy\'arf\'as and Lehel. The exact value of $r_{bip}(S(n,m);k)$ is only known when $n=m=1$. Applying the Tur\'an argument in the bipartite setting, here we prove that if $k=2$ and $n\ge m$, or $k\ge3$ and $n\ge 2m$, then $$r_{bip}(S(n,m);k)=kn+1.$$Comment: Added three Corollarie

Faulkner’s “fierce, courageous being”: Narrative and Neuroscience in The Sound and the Fury

William Faulkner’s The Sound and the Fury is written, in part, from a first person, disabled point of view. The narrator of novel’s first chapter is Benjy, an individual with profound intellectual disability. Examining his own work, Faulkner supplies a close reading of The Sound and the Fury in a collection of introductions to the text, answering an important question surrounding the author’s criticism: ‘why write from a first person, disabled point of view. Through this question, Faulkner reveals a continuity of emotion between Benjy, himself, and the reader. This continuity constitutes a metaphoric extension of theories in neuroscience (the engram and Reconsolidation Theory) to The Sound and the Fury’s narrative. Thus, careful examination of Benjy’s story, Faulkner’s introduction, and neuroscientific theories opens up onto an interdisciplinary space wherein the differences between literary criticism and the natural sciences are absolved

Ectopic gene expression and homeotic transformations in arthropods using recombinant Sindbis viruses

AbstractBackground: The morphological diversity of arthropods makes them attractive subjects for studying the evolution of developmental mechanisms. Comparative analyses suggest that arthropod diversity has arisen largely as a result of changes in expression patterns of genes that control development. Direct analysis of how a particular gene functions in a given species during development is hindered by the lack of broadly applicable techniques for manipulating gene expression.Results: We report that the Arbovirus Sindbis can be used to deliver high levels of gene expression in vivo in a number of non-host arthropod species without causing cytopathic effects in infected cells or impairing development. Using recombinant Sindbis virus, we investigated the function of the homeotic gene Ultrabithorax in the development of butterfly wings and beetle embryos. Ectopic Ultrabithorax expression in butterfly forewing imaginal discs was sufficient to cause the transformation of characteristic forewing properties in the adult, including scale morphology and pigmentation, to those of the hindwing. Expression of Ultrabithorax in beetle embryos outside of its endogenous expression domain affected normal development of the body wall cuticle and appendages.Conclusions: The homeotic genes have long been thought to play an important role in the diversification of arthropod appendages. Using recombinant Sindbis virus, we were able to investigate homeotic gene function in non-model arthropod species. We found that Ultrabithorax is sufficient to confer hindwing identity in butterflies and alter normal development of anterior structures in beetles. Recombinant Sindbis virus has broad potential as a tool for analyzing how the function of developmental genes has changed during the diversification of arthropods

Building consensus on water use assessment of livestock production systems and supply chains: outcome and recommendations from the FAO LEAP Partnership

The FAO Livestock Environmental Assessment and Performance (LEAP) Partnership organised a Technical Advisory Group (TAG) to develop reference guidelines on water footprinting for livestock production systems and supply chains. The mandate of the TAG was to i) provide recommendations to monitor the environmental performance of feed and livestock supply chains over time so that progress towards improvement targets can be measured, ii) be applicable for feed and water demand of small ruminants, poultry, large ruminants and pig supply chains, iii) build on, and go beyond, the existing FAO LEAP guidelines and iv) pursue alignment with relevant international standards, specifically ISO 14040 (2006)/ISO 14044 (2006), and ISO 14046 (2014). The recommended guidelines on livestock water use address both impact assessment (water scarcity footprint as defined by ISO 14046, 2014) and water productivity (water use efficiency). While most aspects of livestock water use assessment have been proposed or discussed independently elsewhere, the TAG reviewed and connected these concepts and information in relation with each other and made recommendations towards comprehensive assessment of water use in livestock production systems and supply chains. The approaches to assess the quantity of water used for livestock systems are addressed and the specific assessment methods for water productivity and water scarcity are recommended. Water productivity assessment is further advanced by its quantification and reporting with fractions of green and blue water consumed. This allows the assessment of the environmental performance related to water use of a livestock-related system by assessing potential environmental impacts of anthropogenic water consumption (only “blue water”); as well as the assessment of overall water productivity of the system (including “green” and “blue water” consumption). A consistent combination of water productivity and water scarcity footprint metrics provides a complete picture both in terms of potential productivity improvements of the water consumption as well as minimizing potential environmental impacts related to water scarcity. This process resulted for the first time in an international consensus on water use assessment, including both the life-cycle assessment community with the water scarcity footprint and the water management community with water productivity metrics. Despite the main focus on feed and livestock production systems, the outcomes of this LEAP TAG are also applicable to many other agriculture sector

Ubiquitin E3 Ligase Ring1b/Rnf2 of Polycomb Repressive Complex 1 Contributes to Stable Maintenance of Mouse Embryonic Stem Cells

Polycomb repressive complex 1 (PRC1) core member Ring1b/Rnf2, with ubiquitin E3 ligase activity towards histone H2A at lysine 119, is essential for early embryogenesis. To obtain more insight into the role of Ring1b in early development, we studied its function in mouse embryonic stem (ES) cells.We investigated the effects of Ring1b ablation on transcriptional regulation using Ring1b conditional knockout ES cells and large-scale gene expression analysis. The absence of Ring1b results in aberrant expression of key developmental genes and deregulation of specific differentiation-related pathways, including TGFbeta signaling, cell cycle regulation and cellular communication. Moreover, ES cell markers, including Zfp42/Rex-1 and Sox2, are downregulated. Importantly, retained expression of ES cell regulators Oct4, Nanog and alkaline phosphatase indicates that Ring1b-deficient ES cells retain important ES cell specific characteristics. Comparative analysis of our expression profiling data with previously published global binding studies shows that the genes that are bound by Ring1b in ES cells have bivalent histone marks, i.e. both active H3K4me3 and repressive H3K27me3, or the active H3K4me3 histone mark alone and are associated with CpG-'rich' promoters. However, deletion of Ring1b results in deregulation, mainly derepression, of only a subset of these genes, suggesting that additional silencing mechanisms are involved in repression of the other Ring1b bound genes in ES cells.Ring1b is essential to stably maintain an undifferentiated state of mouse ES cells by repressing genes with important roles during differentiation and development. These genes are characterized by high CpG content promoters and bivalent histone marks or the active H3K4me3 histone mark alone

Attend Me: Attention and Animation in Early Modern Drama

What does it mean to pay attention and what is the cost? This dissertation explores these questions in the context of a historical shift in the value and purpose of the act of attending. In the late sixteenth century attention which was understood as the foundation of devotional practice, was widely recognized as the most important currency of the commercial and court theaters. Playwrights throughout the beginning of the seventeenth century began to experiment with attention as a form of creative labor and means of animating, transforming, or subjugating bodies in performance. I trace these moments of transformative attention in the works of William Shakespeare, Ben Jonson, John Fletcher, Richard Brome and others to examine how a new form attention in performance redrew the boundaries of an increasingly secularized and commodified self. I engage a wide array of primary sources including popular news pamphlets, recipe books, political treatises, and travel narratives that theorize and debate the biopolitics of attention. In our own moment, attention is critical to the latest stage of surveillance capitalism. Corporations monetize and governmental entities monitor what we attend to as they pay close attention to us. Rather than a recent development, I assert that the stakes of and competition for attention, and concomitantly the price of distraction, gained traction on the early modern stage

Analysis of protein products encoded by the polyhomeotic locus, a member of the polycomb-group of genes in drosophila melanogaster

Polyhomeotic (ph) belongs to the Polycomb-Group (PcG) of genes in Drosophila melanogaster. 12 PcG genes have so far been described, originally identified as trans-regulatory repressors of homeotic gene expression. PcG genes interact in multiple heterozygous combinations to mutually enhance gain of function homeotic phenotypes. In addition to homeotic effects, many PcG genes including ph exhibit pleiotropic phenotypes. Two models have been proposed to explain PcG interactions and function: 1) PcG genes form a hierarchical regulatory network which functions to elaborate the correct expression of a subset of members required at specific regulatory targets; 2) PcG members constitute single components of a multimeric protein complex that functions at specific regulatory targets. To further the molecular characterization of ph protein products and better understand its role in the PcG, I have produced a mono-specific polyclonal antiserum to ph proteins. Using this reagent I show that at least 4 distinct ph protein products are produced that are differentially expressed during development. Several correlations between ph phenotypes and ph protein expression are made. As expected from conceptual translation of a ph cDNA, I show that ph proteins are localized in the nucleus. Further analysis shows that ph is a chromatin binding protein that recognizes 80 specific sites on the polytene chromosome including locations of the homeotic gene complexes and several PcG genes. Comparison of ph and. Polycomb binding sites show a striking degree of overlap in which 71 of 80 ph sites are indistinguishable from Pc sites. I show that ph recognizes ectopically located bxd sequences (an upstream regulatory element in the Ubx gene of the bithorax complex) also recognized by Pc, indicating that ph localization is sequence dependent. Co-localization of ph and Pc throughout the genome and at bxd sequences suggest that these proteins either interact directly or function in close proximity at similar target genes. Co-immunoprecipitation experiments done on nuclear extracts show that ph and Pc proteins are present in the same irnmunoprecipitates, providing the first evidence that they associate in a multimeric complex.Medicine, Faculty ofMedical Genetics, Department ofGraduat

Application of Variable Frequency Microwaves in Microwave-Assisted Chemistry: Relevance and Suppression of Arc Discharges on Conductive Catalysts

The application and advantages of variable frequency microwaves (VFM; range, 5.85–6.65 GHz) are reported for the first time in microwave chemistry, particularly when carrying out reactions catalyzed by metallic conductive catalysts so as to avoid the formation of arc discharges, and especially when using a strong microwave absorber such as activated carbon (AC) particulates as supports of metal-based catalysts. Two model reactions performed in low boiling point nonpolar solvents are described wherein arc discharges easily occur under the more conventional fixed frequency microwave (FFM) approach: (i) the synthesis of 4-methylbiphenyl (4MBP) by the Suzuki-Miyaura cross-coupling process catalyzed by Pd particles supported on AC particulates (Pd/AC), and (ii) the synthesis of toluene via the dehydrogenation of methylcyclohexane (MCH) catalyzed by Pt particles dispersed on AC particulates (Pt/AC). Contrary to the usage of fixed frequency microwaves (5.85 GHz and 6.65 GHz), the use of VFM microwaves increased the chemical yields of 4MBP {49% versus 5–8% after 60 min} and toluene {89% versus 24% after 10 min} by suppressing the formation of discharges that otherwise occur on the catalyst/AC surface with FFM microwaves. Consequently, relative to the latter approach, the VFM technology is significantly advantageous, especially in reactions with solid conductive catalysts, not least of which are the reduction in power consumption, thus energy savings, and the prevention of potential mishaps

How Much is Enough to Learn? Exploring the Effects of an Abbreviated Implementation of the National Writing Project’s College, Career and Community Writers Program (C3WP) on English Learners’ Argumentative Writing Growth

Without doubt, explicit instruction is essential as English learners develop important academic skills such as argument writing. Less clear is the extent to which students need to receive such explicit instruction and engage in practice in order to benefit from it. The National Writing Project’s College, Career, and Community Writing Program (C3WP) provides teachers with resources and assessments for the explicit instruction of argument writing. Prior research on C3WP has indicated that in order to see student growth, teachers must implement at least four short cycles in an academic year. The four cycles can seem ambitious and difficult for teachers to integrate into what they often view to be an already overwhelming curriculum. This small-scale quantitative study, focused on English learners, examines this issue by exploring whether students can experience growth in argument writing in just two cycles of instruction, as opposed to the recommended four cycles. The results of this study suggest that two cycles of instruction are not sufficient in helping English learners improve argument writing skills and that teachers need to commit to at least four cycles to see growth