12,320 research outputs found
Entanglement of two distant Bose-Einstein condensates by detection of Bragg-scattered photons
We show that it is possible to generate entanglement between two distant
Bose-Einstein condensates by detection of Hanbury Brown-Twiss type correlations
in photons Bragg-scattered by the condensates. Upon coincident detection of two
photons by two detectors, the projected joint state of two condensates is shown
to be non-Gaussian. We verify the existence of entanglement by showing that the
partially transposed state is negative. Further we use the inequality in terms
of higher order moments to confirm entanglement. Our proposed scheme can be
generalized for multiple condensates and also for spinor condensates with Bragg
scattering of polarized light with the latter capable of producing hyper
entanglement.Comment: 9 pages, 5 figure
Supersymmetry and Mass Gap in 2+1 Dimensions: A Gauge Invariant Hamiltonian Analysis
A Hamiltonian formulation of Yang-Mills-Chern-Simons theories with supersymmetry in terms of gauge-invariant variables is presented,
generalizing earlier work on nonsupersymmetric gauge theories. Special
attention is paid to the volume measure of integration (over the gauge orbit
space of the fields) which occurs in the inner product for the wave functions
and arguments relating it to the renormalization of the Chern-Simons level
number and to mass-gaps in the spectrum of the Hamiltonians are presented. The
expression for the integration measure is consistent with the absence of mass
gap for theories with extended supersymmetry (in the absence of additional
matter hypermultiplets and/or Chern-Simons couplings), while for the minimally
supersymmetric case, there is a mass-gap, the scale of which is set by a
renormalized level number, in agreement with indications from existing
literature. The realization of the supersymmetry algebra and the Hamiltonian in
terms of the gauge invariant variables is also presented.Comment: 31 pages, References added, typos correcte
A measure of non-convexity in the plane and the Minkowski sum
In this paper a measure of non-convexity for a simple polygonal region in the
plane is introduced. It is proved that for "not far from convex" regions this
measure does not decrease under the Minkowski sum operation, and guarantees
that the Minkowski sum has no "holes".Comment: 5 figures; Discrete and Computational Geometry, 201
An Introduction to Community Detection in Multi-layered Social Network
Social communities extraction and their dynamics are one of the most
important problems in today's social network analysis. During last few years,
many researchers have proposed their own methods for group discovery in social
networks. However, almost none of them have noticed that modern social networks
are much more complex than few years ago. Due to vast amount of different data
about various user activities available in IT systems, it is possible to
distinguish the new class of social networks called multi-layered social
network. For that reason, the new approach to community detection in the
multi-layered social network, which utilizes multi-layered edge clustering
coefficient is proposed in the paper.Comment: M.D. Lytras et al. (Eds.): WSKS 2011, CCIS 278, pp. 185-190, 201
Semantic categories underlying the meaning of ‘place’
This paper analyses the semantics of natural language expressions that are associated with the intuitive notion of ‘place’. We note that the nature of such terms is highly contested, and suggest that this arises from two main considerations: 1) there are a number of logically
distinct categories of place expression, which are not always clearly distinguished in discourse about ‘place’; 2) the many non-substantive place count nouns (such as ‘place’, ‘region’, ‘area’, etc.) employed in natural
language are highly ambiguous. With respect to consideration 1), we propose that place-related expressions
should be classified into the following distinct logical types: a) ‘place-like’ count nouns (further subdivided into abstract, spatial and substantive varieties), b) proper names of ‘place-like’ objects, c) locative property phrases, and d) definite descriptions of ‘place-like’ objects. We outline possible formal representations for each of these. To address consideration 2), we examine meanings, connotations and ambiguities of the English vocabulary of abstract and generic place count nouns, and identify underlying elements of meaning, which explain both
similarities and differences in the sense and usage of the various terms
Analysis of MAGSAT data of the Indian region
Progress in the development of software for reading MAGSAT data tapes and for the reduction of anomaly data, and in the preparation of data for magnetic anomaly maps is reported
A Fresh Approach to the Study of Atmosphere Turbidity
The problem of assessment of atmospheric turbidity caused by aerosol particles, viz., dust, smoke, haze, and other atmospheric pollutants, apart from the effect of variable water vapour content of the atmosphere, has been studied afresh. The basic concept underlying Linke's turbidity factor, T has been found to be theoretically sound, although its quantitative formulation suffers from one major defect, viz, its 'virtual variation' with air mass. This error has been traced to defective formulation of the quantitative expression for T. A 'Rational turbidity factor', Tr, has been proposed which is likely to overcome the limitations of Linke's turbidity factor, T. A nomogram has been development for quick evaluation of Tr, and the effect of altitude has also been considered
Supersymmetric Wilson loops in diverse dimensions
archiveprefix: arXiv primaryclass: hep-th reportnumber: AEI-2009-036, HU-EP-09-15 slaccitation: %%CITATION = ARXIV:0904.0455;%%archiveprefix: arXiv primaryclass: hep-th reportnumber: AEI-2009-036, HU-EP-09-15 slaccitation: %%CITATION = ARXIV:0904.0455;%%archiveprefix: arXiv primaryclass: hep-th reportnumber: AEI-2009-036, HU-EP-09-15 slaccitation: %%CITATION = ARXIV:0904.0455;%
Single-strand selective monofunctional uracil-DNA glycosylase (SMUG1) deficiency is linked to aggressive breast cancer and predicts response to adjuvant therapy
Uracil in DNA is an important cause of mutagenesis. SMUG1 is a uracil DNA glycosylase that removes uracil through base excision repair. SMUG1 also processes radiation induced oxidative base damage as well as 5-fluorouracil incorporated into DNA during chemotherapy. We investigated SMUG1 mRNA expression in 249 primary breast cancers. SMUG1 protein expression was investigated in 1165 breast tumours randomised into two cohorts [training set (n=583) and test set (n=582)]. SMUG1 and chemotherapy response was also investigated in a series of 315 ER negative tumours (n=315). For mechanistic insights, SMUG1 was correlated to biomarkers of aggressive phenotype, DNA repair, cell cycle and apoptosis. Low SMUG1 mRNA expression was associated with adverse disease specific survival (p=0.008) and disease free survival (p=0.008). Low SMUG1 protein expression (25%) was associated with high histological grade (p<0.0001), high mitotic index (p<0.0001), pleomorphism (p<0.0001), glandular de-differentiation (p=0.0001), absence of hormonal receptors (ER-/PgR-/AR) (p<0.0001), presence of basal-like (p<0.0001) and triple negative phenotypes (p<0.0001). Low SMUG1 protein expression was associated with loss of BRCA1 (p<0.0001), ATM (p<0.0001) and XRCC1 (p<0.0001). Low p27 (p<0.0001), low p21 (p=0.023), mutant p53 (p=0.037), low MDM2 (p<0.0001), low MDM4 (p=0.004), low Bcl-2 (p=0.001), low Bax (p=0.003) and high MIB1 (p<0.0001) were likely in low SMUG1 tumours. Low SMUG1 protein expression was associated with poor prognosis in univariate (p<0.001) and multivariate analysis (p<0.01). In ER+ cohort that received adjuvant endocrine therapy, low SMUG1 protein expression remains associated with poor survival (p<0.01). In ER- cohort that received adjuvant chemotherapy, low SMUG1 protein expression is associated with improved survival (p=0.043). Our study suggests that low SMUG1 expression may correlate to adverse clinicopathological features and predict response to adjuvant therapy in breast cancer
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