Unusual echocardiographic finding leading to diagnosis of pulmonary sequestration

Pulmonary sequestration is an embryonic mass of non- functioning lung tissue that does not communicate with the tracheobronchial tree and has a reported incidence of 0.15%-6.4% of all the pulmonary malformations. This anomaly is classified as either intralobar or extralobar with the later variety lying outside the normal investment of visceral pleura. The arterial supply is predominantly by an anomalous artery usually arising from either abdominal or thoracic aorta, while the venous drainage occurs commonly via systemic rather than pulmonary veins. Identification of the anomalous arterial supply has therapeutic implication because the majority of infants clinically present large shunt lesions attributed to these channels in early infancy. The diagnosis in such cases is usually established by computed tomography (CT), angiography, magnetic resonance angiography and conventional angiography. This article reports a 28 day old neonate who presented with features of large shunt lesion, in which echocardiography was instrumental in the diagnosis of a large collateral supplying the sequestrated lung.peer-reviewe

Implementation of higher-order absorbing boundary conditions for the Einstein equations

We present an implementation of absorbing boundary conditions for the Einstein equations based on the recent work of Buchman and Sarbach. In this paper, we assume that spacetime may be linearized about Minkowski space close to the outer boundary, which is taken to be a coordinate sphere. We reformulate the boundary conditions as conditions on the gauge-invariant Regge-Wheeler-Zerilli scalars. Higher-order radial derivatives are eliminated by rewriting the boundary conditions as a system of ODEs for a set of auxiliary variables intrinsic to the boundary. From these we construct boundary data for a set of well-posed constraint-preserving boundary conditions for the Einstein equations in a first-order generalized harmonic formulation. This construction has direct applications to outer boundary conditions in simulations of isolated systems (e.g., binary black holes) as well as to the problem of Cauchy-perturbative matching. As a test problem for our numerical implementation, we consider linearized multipolar gravitational waves in TT gauge, with angular momentum numbers l=2 (Teukolsky waves), 3 and 4. We demonstrate that the perfectly absorbing boundary condition B_L of order L=l yields no spurious reflections to linear order in perturbation theory. This is in contrast to the lower-order absorbing boundary conditions B_L with L<l, which include the widely used freezing-Psi_0 boundary condition that imposes the vanishing of the Newman-Penrose scalar Psi_0.Comment: 25 pages, 9 figures. Minor clarifications. Final version to appear in Class. Quantum Grav

New Approximability Results for the Robust k-Median Problem

We consider a robust variant of the classical $k$-median problem, introduced by Anthony et al. \cite{AnthonyGGN10}. In the \emph{Robust $k$-Median problem}, we are given an $n$-vertex metric space $(V,d)$ and $m$ client sets $\set{S_i \subseteq V}_{i=1}^m$. The objective is to open a set $F \subseteq V$ of $k$ facilities such that the worst case connection cost over all client sets is minimized; in other words, minimize $\max_{i} \sum_{v \in S_i} d(F,v)$. Anthony et al.\ showed an $O(\log m)$ approximation algorithm for any metric and APX-hardness even in the case of uniform metric. In this paper, we show that their algorithm is nearly tight by providing $\Omega(\log m/ \log \log m)$ approximation hardness, unless ${\sf NP} \subseteq \bigcap_{\delta >0} {\sf DTIME}(2^{n^{\delta}})$. This hardness result holds even for uniform and line metrics. To our knowledge, this is one of the rare cases in which a problem on a line metric is hard to approximate to within logarithmic factor. We complement the hardness result by an experimental evaluation of different heuristics that shows that very simple heuristics achieve good approximations for realistic classes of instances.Comment: 19 page

Mesomorphic properties of alkoxybenzylidene- aminoacetophenones

Liquid crystal phase transitions in compounds of alkoxybenzylidene-aminoacetophene serie

The Ironies of Human Mind: A Case of Rett Syndrome

Background: Rett Syndrome (RS) is a chromosome X-linked genetic neurological disorder characterized by developmental regression, particularly in relation to expressive language and use of the hands. It is also associated with profound mental retardation and almost exclusively affects females.Case Details: A four and a half year old girl reported to our dental OPD for a dental checkup. On complete examination, she was diagnosed to be suffering from Rett Syndrome. Preventive therapies and proper oral hygiene instructions were explained to her mother.Conclusion: Early diagnosis of such disorders is extremely important along with treatment of patients’ problems with love and care to prevent them from further pain and stress.Keyowrds: Rett Syndrome, stereotypic hand movements, behavior therapy

On the NP-Hardness of Approximating Ordering Constraint Satisfaction Problems

We show improved NP-hardness of approximating Ordering Constraint Satisfaction Problems (OCSPs). For the two most well-studied OCSPs, Maximum Acyclic Subgraph and Maximum Betweenness, we prove inapproximability of $14/15+\epsilon$ and $1/2+\epsilon$. An OCSP is said to be approximation resistant if it is hard to approximate better than taking a uniformly random ordering. We prove that the Maximum Non-Betweenness Problem is approximation resistant and that there are width-$m$ approximation-resistant OCSPs accepting only a fraction $1 / (m/2)!$ of assignments. These results provide the first examples of approximation-resistant OCSPs subject only to P $\neq$ \NP

Free Convection Flow with Constant Heat Sources in a Porous Channel

The effect of constant heat sources on fully developed free convection flow of a viscous fluid in a porous channel oriented in the direction of the body force has been studied when the walls are maintained at constant temperatures. It has been found that both the velocity and temperature depend on the heat source parameter alpha and the dimensional group Q representing the free convection effects

Blackbody radiation shift in a 43Ca+ ion optical frequency standard

Motivated by the prospect of an optical frequency standard based on 43Ca+, we calculate the blackbody radiation (BBR) shift of the 4s_1/2-3d_5/2 clock transition, which is a major component of the uncertainty budget. The calculations are based on the relativistic all-order single-double method where all single and double excitations of the Dirac-Fock wave function are included to all orders of perturbation theory. Additional calculations are conducted for the dominant contributions in order to evaluate some omitted high-order corrections and estimate the uncertainties of the final results. The BBR shift obtained for this transition is 0.38(1) Hz. The tensor polarizability of the 3d_5/2 level is also calculated and its uncertainty is evaluated as well. Our results are compared with other calculations.Comment: 4 page