448 research outputs found
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 Jassâ and Klintrupâs criteria for peritumoural infiltrate. Pathological data were taken from the reports at that time.
<b>Results</b>: Low-grade inflammatory infiltrate assessed using Klintrupâs 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 Klintrupâs 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
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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, ÎČ and Îł) 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
Flow cytometry and growthâbased analysis of the effects of fruit sanitation on the physiology of Escherichia coli in orange juice
Chlorineâbased solutions are commonly used to sanitize orange fruits prior to juice extraction. We used flow cytometry (FCM) to investigate the physiology of Escherichia coli following its subjection to chlorineâbased solutions and alternative sanitizing agents (H2O2 and organic acids). Green fluorescent protein (GFP)âgenerating E. coli Kâ12 were washed with 50â200 ppm available chlorine (AC), 1%â5% H2O2, 2%â4% citric acid, 4% acetic acid, or 4% lactic acid, after which they were added to 1.2 ÎŒmâfiltered orange juice (OJ). Cell physiology was investigated with FCM during storage at 4°C, and culturability was determined using plate counting. Analysis of GFP fluorescence allowed estimation of intracellular pH (pHi). FCM results demonstrated an inverse relationship between the concentration of AC or H2O2 and cellular health in OJ. Higher concentrations of sanitizer also resulted in a significantly greater number of viable but nonculturable (VBNC) cells. Realâtime FCM showed that supplementation of AC with 2% citric acid, but not with 100 ppm of Tweenâ80, led to a significant reduction in pHi of the cells incubated in OJ, and that the majority of the reduction in pHi occurred during the first 2 min of incubation in OJ. Organic acids were found to be more effective than both AC and H2O2 in reducing the pHi, viability, and culturability of the cells in OJ. The results confirmed the hypothesis that consecutive subjection of E. coli to maximum legally permitted concentrations of sanitizers and OJ induces the VBNC state. Furthermore, we demonstrate successful application of FCM for monitoring the efficacy of washing procedure
The association between failed quit attempts and increased levels of psychological distress in smokers in a large New Zealand cohort
<p>Abstract</p> <p>Background</p> <p>Although the association between smoking status and poorer mental health has been well documented, the association between quit status and psychological distress is less clear. The aim of the present study is to investigate the association of smoking status and quit status with psychological distress.</p> <p>Methods</p> <p>Data for this study is from a single year of the Survey of Families, Income and Employment (SoFIE) conducted in New Zealand (2004/05) (n = 18,525 respondents). Smoking status and quit status were treated as exposure variables, and psychological distress (Kessler-10) was treated as the outcome variable. Logistic regression analyses were performed to determine the association of smoking with psychological distress in the whole adult population and quit status with psychological distress in the ex- and current-smoking population.</p> <p>Results</p> <p>Current smokers had higher rates of high and very high psychological distress compared to never smokers (adjusted odds ratio (aOR) = 1.45; 95% CI: 1.24-1.69). Unsuccessful quitters had much higher levels of high to very high levels of psychological distress (16%) than any other group. Moreover, compared to long-term ex-smokers, unsuccessful quitters had a much higher odds of high to very high levels of psychological distress (aOR = 1.73; 95% CI: 1.36-2.21).</p> <p>Conclusion</p> <p>These findings suggest that the significant association between smoking and psychological distress might be partly explained by increased levels of psychological distress among current smokers who made a quit attempt in the last year. This issue needs further study as it has implications for optimising the design of quitting support.</p
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