The Dynamics of a Strongly Driven Two Component Bose-Einstein Condensate

We consider a two component Bose-Einstein condensate in two spatially localized modes of a double well potential, with periodic modulation of the tunnel coupling between the two modes. We treat the driven quantum field using a two mode expansion and define the quantum dynamics in terms of the Floquet Operator for the time periodic Hamiltonian of the system. It has been shown that the corresponding semiclassical mean-field dynamics can exhibit regions of regular and chaotic motion. We show here that the quantum dynamics can exhibit dynamical tunneling between regions of regular motion, centered on fixed points (resonances) of the semiclassical dynamics

Tumour inflammatory infiltrate predicts survival following curative resection for node-negative colorectal cancer

<b>Background</b>: A pronounced tumour inflammatory infiltrate is known to confer a good outcome in colorectal cancer. Klintrup and colleagues reported a structured assessment of the inflammatory reaction at the invasive margin scoring low grade or high grade. The aim of the present study was to examine the prognostic value of tumour inflammatory infiltrate in node-negative colorectal cancer. <b>Methods</b>: Two hundred patients had undergone surgery for node-negative colorectal cancer between 1997 and 2004. Specimens were scored with Jass’ and Klintrup’s criteria for peritumoural infiltrate. Pathological data were taken from the reports at that time. <b>Results</b>: Low-grade inflammatory infiltrate assessed using Klintrup’s criteria was an independent prognostic factor in node-negative disease. In patients with a low-risk Petersen Index (n = 179), low-grade infiltrate carried a threefold increased risk of cancer death. Low-grade infiltrate was related to increasing T stage and an infiltrating margin. <b>Conclusion</b>: Assessment of inflammatory infiltrate using Klintrup’s criteria provides independent prognostic information on node-negative colorectal cancer. A high-grade local inflammatory response may represent effective host immune responses impeding tumour growth

The dynamics of a strongly driven two component Bose-Einstein Condensate

We consider a two component Bose-Einstein condensate in two spatially localized modes of a double well potential, with periodic modulation of the tunnel coupling between the two modes. We treat the driven quantum field using a two mode expansion and define the quantum dynamics in terms of the Floquet Operator for the time periodic Hamiltonian of the system. It has been shown that the corresponding semiclassical mean-field dynamics can exhibit regions of regular and chaotic motion. We show here that the quantum dynamics can exhibit dynamical tunneling between regions of regular motion, centered on fixed points (resonances) of the semiclassical dynamics

RNA-seq reveals the RNA binding proteins, Hfq and RsmA, play various roles in virulence, antibiotic production and genomic flux in Serratia sp. ATCC 39006.

Background: Serratia sp. ATCC 39006 (S39006) is a Gram-negative enterobacterium that is virulent in plant and animal models. It produces a red-pigmented trypyrrole secondary metabolite, prodigiosin (Pig), and a carbapenem antibiotic (Car), as well as the exoenzymes, pectate lyase and cellulase. Secondary metabolite production in this strain is controlled by a complex regulatory network involving quorum sensing (QS). Hfq and RsmA (two RNA binding proteins and major post-transcriptional regulators of gene expression) play opposing roles in the regulation of several key phenotypes within S39006. Prodigiosin and carbapenem production was abolished, and virulence attenuated, in an S39006 ∆hfq mutant, while the converse was observed in an S39006 rsmA transposon insertion mutant.Results: In order to define the complete regulon of Hfq and RsmA, deep sequencing of cDNA libraries (RNA-seq) was used to analyse the whole transcriptome of S39006 ∆hfq and rsmA::Tn mutants. Moreover, we investigated global changes in the proteome using an LC-MS/MS approach. Analysis of differential gene expression showed that Hfq and RsmA directly or indirectly regulate (at the level of RNA) 4% and 19% of the genome, respectively, with some correlation between RNA and protein expression. Pathways affected include those involved in antibiotic regulation, virulence, flagella synthesis, and surfactant production. Although Hfq and RsmA are reported to activate flagellum production in E. coli and an adherent-invasive E. coli hfq mutant was shown to have no flagella by electron microscopy, we found that flagellar production was increased in the S39006 rsmA and hfq mutants. Additionally, deletion of rsmA resulted in greater genomic flux with increased activity of two mobile genetic elements. This was confirmed by qPCR and analysis of rsmA culture supernatant revealed the presence of prophage DNA and phage particles. Finally, expression of a hypothetical protein containing DUF364 increased prodigiosin production and was controlled by a putative 5′ cis-acting regulatory RNA element. Conclusion: Using a combination of transcriptomics and proteomics this study provides a systems-level understanding of Hfq and RsmA regulation and identifies similarities and differences in the regulons of two major regulators. Additionally our study indicates that RsmA regulates both core and variable genome regions and contributes to genome stability

Population Monte Carlo algorithms

We give a cross-disciplinary survey on ``population'' Monte Carlo algorithms. In these algorithms, a set of ``walkers'' or ``particles'' is used as a representation of a high-dimensional vector. The computation is carried out by a random walk and split/deletion of these objects. The algorithms are developed in various fields in physics and statistical sciences and called by lots of different terms -- ``quantum Monte Carlo'', ``transfer-matrix Monte Carlo'', ``Monte Carlo filter (particle filter)'',``sequential Monte Carlo'' and ``PERM'' etc. Here we discuss them in a coherent framework. We also touch on related algorithms -- genetic algorithms and annealed importance sampling.Comment: Title is changed (Population-based Monte Carlo -> Population Monte Carlo). A number of small but important corrections and additions. References are also added. Original Version is read at 2000 Workshop on Information-Based Induction Sciences (July 17-18, 2000, Syuzenji, Shizuoka, Japan). No figure

RsmA, RsmC and FlhDC regulate sdhEygfX in Serratia

SdhE is required for the flavinylation and activation of succinate dehydrogenase and fumarate reductase (FRD). In addition, SdhE is conserved in proteobacteria (α, β and γ) and eukaryotes. Although the function of this recently characterized family of proteins has been determined, almost nothing is known about how their genes are regulated. Here, the RsmA (CsrA) and RsmC (HexY) post-transcriptional and post-translational regulators have been identified and shown to repress sdhEygfX expression in Serratia sp. ATCC 39006. Conversely, the flagella master regulator complex, FlhDC, activated sdhEygfX transcription. To investigate the hierarchy of control, we developed a novel approach that utilized endogenous CRISPR (clustered regularly interspaced short palindromic repeats)-Cas (CRISPR associated) genome-editing by a type I-F system to generate a chromosomal point mutation in flhC. Mutation of flhC alleviated the ability of RsmC to repress sdhEygfX expression, whereas RsmA acted in both an FlhDC-dependent and -independent manner to inhibit sdhEygfX. Mutation of rsmA or rsmC, or overexpression of FlhDC, led to increased prodigiosin, biosurfactant, swimming and swarming. Consistent with the modulation of sdhE by motility regulators, we have demonstrated that SdhE and FRD are required for maximal flagella-dependent swimming. Together, these results demonstrate that regulators of both metabolism and motility (RsmA, RsmC and FlhDC) control the transcription of the sdhEygfX operon.This work was supported by the Marsden Fund, Royal Society of New Zealand (RSNZ) to PCF and a Strategic Grant from the Otago School of Medical Sciences (OSMS) to MB. HGH was supported by a University of Otago Doctoral Scholarship, MBM by a Division of Health Sciences Career Development Post-doctoral Fellowship, BN by a Dean's Prestigious Summer Scholarship from the OSMS and PCF was supported by a Rutherford Discovery Fellowship (RSNZ). NRW and GPCS were supported by Biotechnology and Biological Sciences Research Council (BBSRC), UK awards to the GPCS laboratory. We thank members of the Fineran and Cook laboratories for helpful discussions, Tim Blower for plasmid pTRB32 and for critically reading the manuscript.This is the final version of the article. It first appeared from the Microbiology Society via http://dx.doi.org/10.1099/mic.0.00028

Competitive nationalism:state, class, and the forms of capital in devolved Scotland

Devolved government in Scotland actively reconstitutes the unequal conditions of social class reproduction. Recognition of state-led class reconstitution draws upon the social theory of Bourdieu. Our analysis of social class in devolved Scotland revisits theories that examine the state as a `power container'. A range of state-enabling powers regulate the legal, economic, social, and cultural containers of class relations as specific forms of what Bourdieu called economic, social, and cultural `capital'. The preconditions of class reproduction are structured in direct ways by the Scottish state as a wealth container but also, more indirectly, as a cultural container and a social container. Competitive nationalism in the devolved Scottish state enacts neoliberal policies as a class- specific worldview but, at the same time, discursively frames society as a panclass national fraternity in terms of distinctive Scottish values of welfare nationalism. Nationalism is able to express this ambiguity in symbolic ways in which the partisan language of social class cannot

The essential peptidoglycan glycosyltransferase MurG forms a complex with proteins involved in lateral envelope growth as well as with proteins involved in cell division in Escherichia coli

In Escherichia coli many enzymes including MurG are directly involved in the synthesis and assembly of peptidoglycan. MurG is an essential glycosyltransferase catalysing the last intracellular step of peptidoglycan synthesis. To elucidate its role during elongation and division events, localization of MurG using immunofluorescence microscopy was performed. MurG exhibited a random distribution in the cell envelope with a relatively higher intensity at the division site. This mid-cell localization was dependent on the presence of a mature divisome. Its localization in the lateral cell wall appeared to require the presence of MreCD. This could be indicative of a potential interaction between MurG and other proteins. Investigating this by immunoprecipitation revealed the association of MurG with MreB and MraY in the same protein complex. In view of this, the loss of rod shape of ΔmreBCD strain could be ascribed to the loss of MurG membrane localization. Consequently, this could prevent the localized supply of the lipid II precursor to the peptidoglycan synthesizing machinery involved in cell elongation. It is postulated that the involvement of MurG in the peptidoglycan synthesis concurs with two complexes, one implicated in cell elongation and the other in division. A model representing the first complex is proposed