Factorization for generic jet production

Factorization is the central ingredient in any theoretical prediction for collider experiments. We introduce a factorization formalism that can be applied to any desired observable, like event shapes or jet observables, for any number of jets and a wide range of jet algorithms in leptonic or hadronic collisions. This is achieved by using soft-collinear effective theory to prove the formal factorization of a generic fully-differential cross section in terms of a hard coefficient, and generic jet and soft functions. In this formalism, whether a given observable factorizes in the usual sense, depends on whether it is inclusive enough, so the jet functions can be calculated perturbatively. The factorization formula for any such observable immediately follows from our general result, including the precise definition of the jet and soft functions appropriate for the observable in question. As examples of our formalism, we work out several results in two-jet production for both e+e- and pp collisions. For the latter, we also comment on how our formalism allows one to treat underlying events and beam remnants.Comment: 33 pages, v2: minor typos corrected, journal versio

Coming to America: Multiple Origins of New World Geckos

Geckos in the Western Hemisphere provide an excellent model to study faunal assembly at a continental scale. We generated a time-calibrated phylogeny, including exemplars of all New World gecko genera, to produce a biogeographic scenario for the New World geckos. Patterns of New World gecko origins are consistent with almost every biogeographic scenario utilized by a terrestrial vertebrate with different New World lineages showing evidence of vicariance, dispersal via temporary land bridge, overseas dispersal, or anthropogenic introductions. We also recovered a strong relationship between clade age and species diversity, with older New World lineages having more species than more recently arrived lineages. Our data provide the first phylogenetic hypothesis for all New World geckos and highlight the intricate origins and ongoing organization of continental faunas. The phylogenetic and biogeographical hypotheses presented here provide an historical framework to further pursue research on the diversification and assembly of the New World herpetofauna

Introduction: Is This What Democracy Looks Like?

Introductory article for the site 'Is This What Democracy Looks Like?'. "This dossier takes its cue from one of the Occupy movement’s bedrock slogans, 'This Is What Democracy Looks Like' (though the catchword was first nurtured, as were many Occupy paradigms, tactics, and customs, in the global justice movement that came of age in Seattle in 1999). This proud assertion, stiffened by populist certitudes about the '99%' hypermajority, exercised a clear appeal to protesters. It is self-congratulatory, confrontational, and also quite articulate as a political statement. Not everyone has to believe the slogan to chant it. But what if it were taken up as a more literal goal? What if the Occupy model of horizontalism, explicated below, were to be pushed into every venue of civil society, eventually supplanting the roots of our representative democracy system? Who would gain and who would lose? How would our own institutions, organizations, and networks be transformed in the process? The radical innocence of Occupy allowed such questions to be asked. After more than a year of operations under its name, the record allows some provisional answers to be offered.

Introduction: Is This What Democracy Looks Like?

Introductory article for the site 'Is This What Democracy Looks Like?'. "This dossier takes its cue from one of the Occupy movement’s bedrock slogans, 'This Is What Democracy Looks Like' (though the catchword was first nurtured, as were many Occupy paradigms, tactics, and customs, in the global justice movement that came of age in Seattle in 1999). This proud assertion, stiffened by populist certitudes about the '99%' hypermajority, exercised a clear appeal to protesters. It is self-congratulatory, confrontational, and also quite articulate as a political statement. Not everyone has to believe the slogan to chant it. But what if it were taken up as a more literal goal? What if the Occupy model of horizontalism, explicated below, were to be pushed into every venue of civil society, eventually supplanting the roots of our representative democracy system? Who would gain and who would lose? How would our own institutions, organizations, and networks be transformed in the process? The radical innocence of Occupy allowed such questions to be asked. After more than a year of operations under its name, the record allows some provisional answers to be offered.

Polymerisable octahedral rhenium cluster complexes as precursors for photo/electroluminescent polymers

New polymerisable photoluminescent octahedral rhenium cluster complexes trans-[{Re₆Q₈}(TBP)₄VB)₂] (Q = S or Se; TBP – p-tert-butylpyridine; VB – vinyl benzoate) have been synthesised, characterised and used to construct rhe-nium cluster-organic polymer hybrid materials. These novel polymer systems are solution-processable and the rhenium clusters retain their photoluminescent properties within the polymer environment. Notably, when the rhenium cluster complexes are incorporated into the matrix of the electroluminescent polymer poly(N-vinylcarbazole), the resultant cluster polymer hybrid combined properties of both components and was used successfully in the construc-tion of a polymer light emitting diode (PLED). These prototype devices are the first PLEDs to incorporate octahedral rhenium clusters and provide the first direct evidence of the electroluminescent properties of rhenium clusters and indeed, to the best of our knowledge, of any member of the family of 24-electron hexanuclear cluster complexes of molybdenum, tungsten or rhenium

Genetic and systems level analysis of Drosophila sticky/citron kinase and dFmr1 mutants reveals common regulation of genetic networks

<p>Abstract</p> <p>Background</p> <p>In <it>Drosophila</it>, the genes <it>sticky </it>and <it>dFmr1 </it>have both been shown to regulate cytoskeletal dynamics and chromatin structure. These genes also genetically interact with Argonaute family microRNA regulators. Furthermore, in mammalian systems, both genes have been implicated in neuronal development. Given these genetic and functional similarities, we tested <it>Drosophila sticky </it>and <it>dFmr1 </it>for a genetic interaction and measured whole genome expression in both mutants to assess similarities in gene regulation.</p> <p>Results</p> <p>We found that <it>sticky </it>mutations can dominantly suppress a <it>dFmr1 </it>gain-of-function phenotype in the developing eye, while phenotypes produced by RNAi knock-down of <it>sticky </it>were enhanced by <it>dFmr1 </it>RNAi and a <it>dFmr1 </it>loss-of-function mutation. We also identified a large number of transcripts that were misexpressed in both mutants suggesting that <it>sticky </it>and <it>dFmr1 </it>gene products similarly regulate gene expression. By integrating gene expression data with a protein-protein interaction network, we found that mutations in <it>sticky </it>and <it>dFmr1 </it>resulted in misexpression of common gene networks, and consequently predicted additional specific phenotypes previously not known to be associated with either gene. Further phenotypic analyses validated these predictions.</p> <p>Conclusion</p> <p>These findings establish a functional link between two previously unrelated genes. Microarray analysis indicates that <it>sticky </it>and <it>dFmr1 </it>are both required for regulation of many developmental genes in a variety of cell types. The diversity of transcripts regulated by these two genes suggests a clear cause of the pleiotropy that <it>sticky </it>and <it>dFmr1 </it>mutants display and provides many novel, testable hypotheses about the functions of these genes. As both of these genes are implicated in the development and function of the mammalian brain, these results have relevance to human health as well as to understanding more general biological processes.</p

Development of Vortex Bioreactor Technology for Decentralised Water Treatment

The vortex bioreactor (VBR) is a simple decentralised water treatment system (DeWaTS) that sits at the interface between swirl flow, biotechnology and chemical engineering. The device utilises swirl flow and suspended activated beads to achieve downstream water processing and has been tested for applications including centrifugal-driven separation, pathogen neutralisation and metal absorption. The VBR was optimised for the treatment of faecally contaminated effluents in the developing world, and the design features related to the key challenges faced by the wastewater industry are highlighted here. The VBR has two aspects that can be modified to generate different reactor conditions: the impeller, where the swirl flow is modified through alterations of rotation speed, and impeller geometry and the suspended activated beads, which facilitate mixing and alter the reactor surface area. Data from testing for some of the different applications mentioned above are presented here, and future planned developments for the technology are discussed

Non-global Structure of the O({\alpha}_s^2) Dijet Soft Function

High energy scattering processes involving jets generically involve matrix elements of light- like Wilson lines, known as soft functions. These describe the structure of soft contributions to observables and encode color and kinematic correlations between jets. We compute the dijet soft function to O({\alpha}_s^2) as a function of the two jet invariant masses, focusing on terms not determined by its renormalization group evolution that have a non-separable dependence on these masses. Our results include non-global single and double logarithms, and analytic results for the full set of non-logarithmic contributions as well. Using a recent result for the thrust constant, we present the complete O({\alpha}_s^2) soft function for dijet production in both position and momentum space.Comment: 55 pages, 8 figures. v2: extended discussion of double logs in the hard regime. v3: minor typos corrected, version published in JHEP. v4: typos in Eq. (3.33), (3.39), (3.43) corrected; this does not affect the main result, numerical results, or conclusion

Jet Shapes and Jet Algorithms in SCET

Jet shapes are weighted sums over the four-momenta of the constituents of a jet and reveal details of its internal structure, potentially allowing discrimination of its partonic origin. In this work we make predictions for quark and gluon jet shape distributions in N-jet final states in e+e- collisions, defined with a cone or recombination algorithm, where we measure some jet shape observable on a subset of these jets. Using the framework of Soft-Collinear Effective Theory, we prove a factorization theorem for jet shape distributions and demonstrate the consistent renormalization-group running of the functions in the factorization theorem for any number of measured and unmeasured jets, any number of quark and gluon jets, and any angular size R of the jets, as long as R is much smaller than the angular separation between jets. We calculate the jet and soft functions for angularity jet shapes \tau_a to one-loop order (O(alpha_s)) and resum a subset of the large logarithms of \tau_a needed for next-to-leading logarithmic (NLL) accuracy for both cone and kT-type jets. We compare our predictions for the resummed \tau_a distribution of a quark or a gluon jet produced in a 3-jet final state in e+e- annihilation to the output of a Monte Carlo event generator and find that the dependence on a and R is very similar.Comment: 62 pages plus 21 pages of Appendices, 13 figures, uses JHEP3.cls. v2: corrections to finite parts of NLO jet functions, minor changes to plots, clarified discussion of power corrections. v3: Journal version. Introductory sections significantly reorganized for clarity, classification of logarithmic accuracy clarified, results for non-Mercedes-Benz configurations adde