22,311 research outputs found
Effective Higgs Lagrangian and Constraints on Higgs Couplings
Probing the properties of the discovered Higgs boson may tell us whether or
not it is the same particle as the one predicted by the Standard Model. To this
aim we parametrize deviations of the Higgs couplings to matter from the
Standard Model by using the Higgs Effective Field Theory framework. Starting
with a general dimension-6 effective Lagrangian including both CP-even and
CP-odd operators, and requiring that the operators do not introduce power
divergences in the oblique parameters, we reduce the number of independent
effective couplings of the theory. This framework is then used to put updated
constraints on the effective couplings, using the latest Higgs rates data from
the Run-I of the ATLAS and CMS experiments, and electroweak precision data from
LEP, SLC and Tevatron. We show that the current data is able to significantly
constrain the CP-even and some CP-odd operators of the effective Lagrangian.Comment: 34 pages, 6 figures; v2: some issues clarified, updated references,
updated fit with latest data from Run-I of ATLAS and CMS (see text for
details
Spectral-Variation Bounds in Hyperbolic Geometry
We derive new estimates for distances between optimal matchings of
eigenvalues of non-normal matrices in terms of the norm of their difference. We
introduce and estimate a hyperbolic metric analogue of the classical
spectral-variation distance. The result yields a qualitatively new and simple
characterization of the localization of eigenvalues. Our bound improves on the
best classical spectral-variation bounds due to Krause if the distance of
matrices is sufficiently small and is sharp for asymptotically large matrices.
Our approach is based on the theory of model operators, which provides us with
strong resolvent estimates. The latter naturally lead to a Chebychev-type
interpolation problem with finite Blaschke products, which can be solved
explicitly and gives stronger bounds than the classical Chebychev interpolation
with polynomials. As compared to the classical approach our method does not
rely on Hadamard's inequality and immediately generalize to algebraic operators
on Hilbert space.Comment: 19 pages, 4 pictures, Linear Algebra and its Applications, Volume
482, 1 October 201
All unital qubit channels are -noisy operations
We show that any unital qubit channel can be implemented by letting the input
system interact unitarily with a -dimensional environment in the maximally
mixed state and then tracing out the environment. We also provide an example
where the dimension of such an environment has to be at least .Comment: 8 pages, no picture
Financial reform and information problems in capital markets: an empirical analysis of the Chilean experience, 1983-1992
This paper introduces a general, formal treatment of dynamic constraints, i.e., constraints on the state changes that are allowed in a given state space. Such dynamic constraints can be seen as representations of "real world" constraints in a managerial context. The notions of transition, reversible and irreversible transition, and transition relation will be introduced. The link with Kripke models (for modal logics) is also made explicit. Several (subtle) examples of dynamic constraints will be given. Some important classes of dynamic constraints in a database context will be identified, e.g. various forms of cumulativity, non-decreasing values, constraints on initial and final values, life cycles, changing life cycles, and transition and constant dependencies. Several properties of these dependencies will be treated. For instance, it turns out that functional dependencies can be considered as "degenerated" transition dependencies. Also, the distinction between primary keys and alternate keys is reexamined, from a dynamic point of view.
Yin Yang 1 is associated with cancer stem cell transcription factors (SOX2, OCT4, BMI1) and clinical implication.
The transcription factor Yin Yang 1 (YY1) is frequently overexpressed in cancerous tissues compared to normal tissues and has regulatory roles in cell proliferation, cell viability, epithelial-mesenchymal transition, metastasis and drug/immune resistance. YY1 shares many properties with cancer stem cells (CSCs) that drive tumorigenesis, metastasis and drug resistance and are regulated by overexpression of certain transcription factors, including SOX2, OCT4 (POU5F1), BMI1 and NANOG. Based on these similarities, it was expected that YY1 expression would be associated with SOX2, OCT4, BMI1, and NANOG's expressions and activities. Data mining from the proteomic tissue-based datasets from the Human Protein Atlas were used for protein expression patterns of YY1 and the four CSC markers in 17 types of cancer, including both solid and hematological malignancies. A close association was revealed between the frequency of expressions of YY1 and SOX2 as well as SOX2 and OCT4 in all cancers analyzed. Two types of dynamics were identified based on the nature of their association, namely, inverse or direct, between YY1 and SOX2. These two dynamics define distinctive patterns of BMI1 and OCT4 expressions. The relationship between YY1 and SOX2 expressions as well as the expressions of BMI1 and OCT4 resulted in the classification of four groups of cancers with distinct molecular signatures: (1) Prostate, lung, cervical, endometrial, ovarian and glioma cancers (YY1(lo)SOX2(hi)BMI1(hi)OCT4(hi)) (2) Skin, testis and breast cancers (YY1(hi)SOX2(lo)BMI1(hi)OCT4(hi)) (3) Liver, stomach, renal, pancreatic and urothelial cancers (YY1(lo)SOX2(lo)BMI1(hi)OCT4(hi)) and (4) Colorectal cancer, lymphoma and melanoma (YY1(hi)SOX2(hi)BMI1(lo)OCT4(hi)). A regulatory loop is proposed consisting of the cross-talk between the NF-kB/PI3K/AKT pathways and the downstream inter-regulation of target gene products YY1, OCT4, SOX2 and BMI1
Fiscal Policy and Private Investment in Less Developed Countries
Private investment, Public investment, Fiscal policy, LDCs
Decomposability of Linear Maps under Tensor Products
Both completely positive and completely copositive maps stay decomposable
under tensor powers, i.e under tensoring the linear map with itself. But are
there other examples of maps with this property? We show that this is not the
case: Any decomposable map, that is neither completely positive nor completely
copositive, will lose decomposability eventually after taking enough tensor
powers. Moreover, we establish explicit bounds to quantify when this happens.
To prove these results we use a symmetrization technique from the theory of
entanglement distillation, and analyze when certain symmetric maps become
non-decomposable after taking tensor powers. Finally, we apply our results to
construct new examples of non-decomposable positive maps, and establish a
connection to the PPT squared conjecture.Comment: 26 pages, 3 figure
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