1,206 research outputs found

    Design Build VoIP Technology Implementation on Network Applications IP Phone Via a Different Intranet Network.

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    Computer network technology and the internet today has become one of the important needs in life activities. Every day continues to grow, the development of a busy discussed and discussed today is the technology that lead to Next Generation Network (NGN) which will most likely be the technology platform on Internet Protocol (IP), one of the technology into use is a softswitch or known by the name Voice over Internet Protocol (VoIP). VoIP Technology able to communicate using voice infrastructure like the Internet using regular phone at no cost to regular phone. In addition, VoIP technology uses voice compression technology to provide efficiency and utilization bandwitdth, so that data communication is not disrupted

    Twisting D(2,1; α) Superspace

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    We develop a three-dimensional N=4 theory of rigid supersymmetry describing the dynamics of a set of hypermultiplets (?I alpha alpha 'alpha?',phi I alpha A) on a curved AdS(3) worldvolume background, whose supersymmetry is captured by the supergroup D2(2,1;alpha). To unveil some remarkable features of this model, we perform two twists, involving the SL(2,R) factors of the theory. After the first twist, our spacetime Lagrangian exhibits a Chern-Simons term associated with an odd one-form field, together with a fermionic "gauge-fixing", in the spirit of the Rozansky-Witten model. The second twist allows to interpret the D2(2,1;alpha) setup as a framework capable of describing massive Dirac particles. In particular, this yields a generalisation of the Alvarez-Valenzuela-Zanelli model of "unconventional supersymmetry". We comment on specific values of the combination alpha+1, which in our model is related to a sort of gauging in the absence of dynamical gauge fields

    Nuevos registros de Hepáticas y Anthocerotófitas para Panamá

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    Twenty eight hepatics and eight hornwort species are reported as new to Panama. Data on their habitat, local and general distribution and are included. One species, Cololejeunea panamensis G. Dauphin & Pócs is described as new to science. A new combination, Megaceros canaliculatus (Pagán) Shaw & Renzaglia, corr. et emend. J. C. Vill. & Salazar Allen, is proposed. Eight further hepatic records from the literature have been added. This raises the total number of hepatics reported from Panama to 325 species in 100 genera and 28 families

    N\mathcal{N}-Extended D=4D=4 Supergravity, Unconventional SUSY and Graphene

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    We derive a 2+12+1 dimensional model with unconventional supersymmetry at the boundary of an AdS4{\rm AdS}_4 N\mathcal{N}-extended supergravity, generalizing previous results. The (unconventional) extended supersymmetry of the boundary model is instrumental in describing, within a top-down approach, the electronic properties of graphene-like 2D materials at the two Dirac points, K{\bf K} and K′{\bf K}'. The two valleys correspond to the two independent sectors of the OSp(p∣2)×OSp(q∣2){\rm OSp}(p|2)\times {\rm OSp}(q|2) boundary model in the p=qp=q case, which are related by a parity transformation. The Semenoff and Haldane-type masses entering the corresponding Dirac equations are identified with the torsion parameters of the substrate in the model.Comment: 27 pages, 1 figur

    N = 2 AdS4 supergravity, holography and Ward identities

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    We develop in detail the holographic framework for an N = 2 pure AdS supergravity model in four dimensions, including all the contributions from the fermionic fields and adopting the Fefferman-Graham parametrization. We work in the first order formalism, where the full superconformal structure can be kept manifest in principle, even if only a part of it is realized as a symmetry on the boundary, while the remainder has a non-linear realization. Our study generalizes the results presented in antecedent literature and includes a general discussion of the gauge-fixing conditions on the bulk fields which yield the asymptotic symmetries at the boundary. We construct the corresponding super- conformal currents and show that they satisfy the related Ward identities when the bulk equations of motion are imposed. Consistency of the holographic setup requires the super- AdS curvatures to vanish at the boundary. This determines, in particular, the expression of the super-Schouten tensor of the boundary theory, which generalizes the purely bosonic Schouten tensor of standard gravity by including gravitini bilinears. The same applies to the superpartner of the super-Schouten tensor, the conformino. Furthermore, the vanishing of the supertorsion poses general constraints on the sources of the three-dimensional boundary conformal field theory and requires that the super-Schouten tensor is endowed with an antisymmetric part proportional to a gravitino-squared term

    Clonal Chromosome Anomalies Affecting Fli1 Mimic Inherited Thrombocytopenia Of The Paris-Trousseau Type

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    Introduction: The thrombocytopenia of the Paris-Trousseau (TCPT) type is a contiguous gene syndrome characterized by mild bleeding tendency, variable thrombocytopenia (THC), abnormal giant alpha-granules in platelets and dysmegakaryopoiesis: it derives from a constitutional deletion of chromosome 11 leading to the loss of FLI1, a transcription factor involved in megakaryocyte differentiation and maturation. Case report: A women with an acquired, isolated THC developing over 10 yr showed morphological features typical of TCPT in platelets and bone marrow (BM). Twenty years after the onset of THC, the other hematological parameters are still normal and the patient is well. Results: Clonal hemopoiesis was shown and chromosome analyses performed on BM revealed a clone with 45 chromosomes and a complex unbalanced translocation involving chromosomes 2, 3, and 11. The anomaly was present in the majority of bone marrow cells but only in a few peripheral blood elements. A microarray-based comparative genomic hybridization defined the deleted region of chromosome 11 including the FLI1 locus that was missing. Conclusion: Although our patient presented with nearly all the characteristics of TCPT, her illness was acquired instead of being inherited and the most appropriate diagnosis is that of the unilineage dysplasia 'refractory THC.' This observation suggests that appropriate cytogenetic investigations should be always considered in patients with acquired THC of unknown origin

    Positive Least Energy Solutions and Phase Separation for Coupled Schrodinger Equations with Critical Exponent: Higher Dimensional Case

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    We study the following nonlinear Schr\"{o}dinger system which is related to Bose-Einstein condensate: {displaymath} {cases}-\Delta u +\la_1 u = \mu_1 u^{2^\ast-1}+\beta u^{\frac{2^\ast}{2}-1}v^{\frac{2^\ast}{2}}, \quad x\in \Omega, -\Delta v +\la_2 v =\mu_2 v^{2^\ast-1}+\beta v^{\frac{2^\ast}{2}-1} u^{\frac{2^\ast}{2}}, \quad x\in \om, u\ge 0, v\ge 0 \,\,\hbox{in \om},\quad u=v=0 \,\,\hbox{on \partial\om}.{cases}{displaymath} Here \om\subset \R^N is a smooth bounded domain, 2∗:=2NN−22^\ast:=\frac{2N}{N-2} is the Sobolev critical exponent, -\la_1(\om)0 and β≠0\beta\neq 0, where \lambda_1(\om) is the first eigenvalue of −Δ-\Delta with the Dirichlet boundary condition. When \bb=0, this is just the well-known Brezis-Nirenberg problem. The special case N=4 was studied by the authors in (Arch. Ration. Mech. Anal. 205: 515-551, 2012). In this paper we consider {\it the higher dimensional case N≥5N\ge 5}. It is interesting that we can prove the existence of a positive least energy solution (u_\bb, v_\bb) {\it for any β≠0\beta\neq 0} (which can not hold in the special case N=4). We also study the limit behavior of (u_\bb, v_\bb) as β→−∞\beta\to -\infty and phase separation is expected. In particular, u_\bb-v_\bb will converge to {\it sign-changing solutions} of the Brezis-Nirenberg problem, provided N≥6N\ge 6. In case \la_1=\la_2, the classification of the least energy solutions is also studied. It turns out that some quite different phenomena appear comparing to the special case N=4.Comment: 48 pages. This is a revised version of arXiv:1209.2522v1 [math.AP
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