2,325 research outputs found

    Cavity Induced Interfacing of Atoms and Light

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    This chapter introduces cavity-based light-matter quantum interfaces, with a single atom or ion in strong coupling to a high-finesse optical cavity. We discuss the deterministic generation of indistinguishable single photons from these systems; the atom-photon entanglement intractably linked to this process; and the information encoding using spatio-temporal modes within these photons. Furthermore, we show how to establish a time-reversal of the aforementioned emission process to use a coupled atom-cavity system as a quantum memory. Along the line, we also discuss the performance and characterisation of cavity photons in elementary linear-optics arrangements with single beam splitters for quantum-homodyne measurements.Comment: to appear as a book chapter in a compilation "Engineering the Atom-Photon Interaction" published by Springer in 2015, edited by A. Predojevic and M. W. Mitchel

    Molecular motors robustly drive active gels to a critically connected state

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    Living systems often exhibit internal driving: active, molecular processes drive nonequilibrium phenomena such as metabolism or migration. Active gels constitute a fascinating class of internally driven matter, where molecular motors exert localized stresses inside polymer networks. There is evidence that network crosslinking is required to allow motors to induce macroscopic contraction. Yet a quantitative understanding of how network connectivity enables contraction is lacking. Here we show experimentally that myosin motors contract crosslinked actin polymer networks to clusters with a scale-free size distribution. This critical behavior occurs over an unexpectedly broad range of crosslink concentrations. To understand this robustness, we develop a quantitative model of contractile networks that takes into account network restructuring: motors reduce connectivity by forcing crosslinks to unbind. Paradoxically, to coordinate global contractions, motor activity should be low. Otherwise, motors drive initially well-connected networks to a critical state where ruptures form across the entire network.Comment: Main text: 21 pages, 5 figures. Supplementary Information: 13 pages, 8 figure

    Technique of anterior colporrhaphy: a Dutch evaluation

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    Contains fulltext : 96395.pdf (publisher's version ) (Closed access)INTRODUCTION AND HYPOTHESIS: To evaluate the variation in techniques of anterior colporrhaphy among members of the Dutch Urogynecologic Society. METHODS: A questionnaire evaluating the technique of anterior colporrhaphy, preoperative and postoperative care, and use of the POP-Q score was sent out by e-mail. RESULTS: One hundred thirty-three completed questionnaires were received. The response rate was 65%. There are large variations in incisions, use of hydrodissection, method of plication, and excision of redundant vaginal epithelium. The urinary catheter was generally removed on day 2 after surgery and the vaginal pack on day 1. Less than half of the respondents used the POP-Q score routinely. CONCLUSIONS: Dutch gynecologists use a variety of surgical techniques to operate on a cystocele. This suggests that there is no widely accepted opinion on the best surgical approach. The lack of differentiation between central and lateral defects is striking and in contrast with the, mostly, American literature

    Jet production in charged current deep inelastic e⁺p scatteringat HERA

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    The production rates and substructure of jets have been studied in charged current deep inelastic e⁺p scattering for Q² > 200 GeV² with the ZEUS detector at HERA using an integrated luminosity of 110.5 pb⁻¹. Inclusive jet cross sections are presented for jets with transverse energies E_{T}^{jet} > 5 GeV. Measurements of the mean subjet multiplicity, 〈n_{sbj}〉, of the inclusive jet sample are presented. Predictions based on parton-shower Monte Carlo models and next-to-leading-order QCD calculations are compared to the measurements. The value of α_{s} (M_{z}), determined from 〈n_{sbj}〉 at y_{cut} = 10⁻² for jets with 25 < E_{T}^{jet} < 119 GeV, is α_{s} (M_{z}) = 0.1202 ± 0.0052 (stat.)_{-0.0019}^{+0.0060} (syst.)_{-0.0053}^{+0.0065} (th.). The mean subjet multiplicity as a function of Q² is found to be consistent with that measured in NC DIS

    Fertility and economic instability: the role of unemployment and job displacement

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    In this paper, we study the separate effects of unemployment and job displacement on fertility in a sample of white collar women in Austria. Using an instrumental variable approach, we show that unemployment incidence as such has no negative effect on fertility decisions, but the very fact of being displaced from a career-oriented job has. Fertility rates for women affected by a firm closure are significantly below those of a control group, even after 6 years, and this is so irrespective of the incidence or the duration of the associated unemployment spell

    Radiological progression of cerebral metastases after radiosurgery: assessment of perfusion MRI for differentiating between necrosis and recurrence

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    To assess the capability of perfusion MRI to differentiate between necrosis and tumor recurrence in patients showing radiological progression of cerebral metastases treated with stereotactic radiosurgery (SRS). From 2004 to 2006 dynamic susceptibility-weighted contrast-enhanced perfusion MRI scans were performed on patients with cerebral metastasis showing radiological progression after SRS during follow-up. Several perfusion MRI characteristics were examined: a subjective visual score of the relative cerebral blood volume (rCBV) map and quantitative rCBV measurements of the contrast-enhanced areas of maximal perfusion. For a total of 34 lesions in 31 patients a perfusion MRI was performed. Diagnoses were based on histology, definite radiological decrease or a combination of radiological and clinical follow-up. The diagnosis of tumor recurrence was obtained in 20 of 34 lesions, and tumor necrosis in 14 of 34. Regression analyses for all measures proved statistically significant (χ2 = 11.6–21.6, P < 0.001–0.0001). Visual inspection of the rCBV map yielded a sensitivity and specificity of 70.0 respectively 92.9%. The optimal cutoff point for maximal tumor rCBV relative to white matter was 2.00 (improving the sensibility to 85.0%) and 1.85 relative to grey matter (GM), improving the specificity to 100%, with a corresponding sensitivity of 70.0%. Perfusion MRI seems to be a useful tool in the differentiation of necrosis and tumor recurrence after SRS. For the patients displaying a rCBV-GM greater than 1.85, the diagnosis of necrosis was excluded. Salvage treatment can be initiated for these patients in an attempt to prolong survival

    Odontogenic tumors and giant cell lesions of jaws - a nine year study

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    <p>Abstract</p> <p>Objectives</p> <p>A definite geographic variation has been observed in the frequency of odontogenic tumors and giant cell lesions of the jaws reported from different parts of the world. However, there are a few studies on these lesions, especially giant cell lesions, reported from India. Hence, this study was designed to provide a demographic data on the odontogenic tumors and giant cell lesions reported from our institute located in the city of Hyderabad. Hyderabad is the capital city of the southern state of Andhra Pradesh in India. A retrospective analysis of odontogenic tumors and giant cell lesions of jaws reported in our institute between the years 2000 and 2009 was done and this data was compared with previous reports from different parts of the world and India.</p> <p>Methods</p> <p>Biopsies of the lesions received between the years 2000 and 2009 were reviewed and patient's history, clinical, radiological and histopathological characteristics were analyzed.</p> <p>Results</p> <p>A total of 77 biopsies were received during the nine year study period. These lesions were more frequently seen in the males, in a younger age group and showed a predilection for the mandible. Most of them presented as radiolucent, slow growing and painless lesions. Ameloblastomas (71.4%) constituted the majority of odontogenic tumors while central giant cell granulomas (7.8%) constituted the majority of giant cell lesions.</p> <p>Conclusion</p> <p>These lesions showed a definite geographic variation with ameloblastomas being the most common odontogenic tumors and odontomas being relatively rarer lesions in our region.</p

    CFH, C3 and ARMS2 Are Significant Risk Loci for Susceptibility but Not for Disease Progression of Geographic Atrophy Due to AMD

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    Age-related macular degeneration (AMD) is a prevalent cause of blindness in Western societies. Variants in the genes encoding complement factor H (CFH), complement component 3 (C3) and age-related maculopathy susceptibility 2 (ARMS2) have repeatedly been shown to confer significant risks for AMD; however, their role in disease progression and thus their potential relevance for interventional therapeutic approaches remains unknown. Here, we analyzed association between variants in CFH, C3 and ARMS2 and disease progression of geographic atrophy (GA) due to AMD. A quantitative phenotype of disease progression was computed based on longitudinal observations by fundus autofluorescence imaging. In a subset of 99 cases with pure bilateral GA, variants in CFH (Y402H), C3 (R102G), and ARMS2 (A69S) are associated with disease (P = 1.6x10(-9), 3.2x10(-3), and P = 2.6x10(-12), respectively) when compared to 612 unrelated healthy control individuals. In cases, median progression rate of GA over a mean follow-up period of 3.0 years was 1.61 mm(2)/year with high concordance between fellow eyes. No association between the progression rate and any of the genetic risk variants at the three loci was observed (P>0.13). This study confirms that variants at CFH, C3, and ARMS2 confer significant risks for GA due to AMD. In contrast, our data indicate no association of these variants with disease progression which may have important implications for future treatment strategies. Other, as yet unknown susceptibilities may influence disease progression
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