Anchored Cutoff Structure Design and Construction

As part of a new cogeneration plant being built in Jacksonville, Florida, a 31-foot deep excavation was required to install a 173-foot by 53-foot coal unloading structure in loose to medium-dense fine sands with shallow ground water. A conventional system of excavation support would typically consist of installing and maintaining a dewatering system and driving sheet piles. However, due to the potential for shallow contaminated ground water at the site and a restricted amount of inflow treatment capacity, a nearly complete cutoff or bathtub structure was required. A system that is relatively new to the United States was designed and installed to meet the difficult needs of the site. The system consisted of a sheet pile perimeter wall placed in a cement-bentonite slurry trench, tied back with soil anchors, in conjunction with an anchored six to eight-foot thick soilcrete base mat installed using jet-grouting techniques. This case history provides details regarding design and installation of the anchored cutoff structure. Specifically, design assumptions regarding lateral earth pressures are presented along with predicted versus actual anchor loads for various construction stages. In addition, the results of finite element seepage analysis of the soilcrete base cutoff, and a unique hydrostatic uplift analysis are also presented

Uniqueness of the asymptotic AdS3 geometry

We explicitly show that in (2+1) dimensions the general solution of the Einstein equations with negative cosmological constant on a neigbourhood of timelike spatial infinity can be obtained from BTZ metrics by coordinate transformations corresponding geometrically to deformations of their spatial infinity surface. Thus, whatever the topology and geometry of the bulk, the metric on the timelike extremities is BTZ.Comment: LaTeX, 8 pages, no figures, version that will appear in Class. Quant. Gra

Gravitational Mass in Asymptotically de Sitter Space-Times with Compactified Dimensions

We define gravitational mass in asymptotically de Sitter space-times with compactified dimension. It was shown that the mass can be negative for space-time with matter spreading beyond the cosmological horizon scale or large outward `momentum' in four dimension. We give simple examples with negative energy in higher dimensions even if the matter is not beyond horizon or system does not have large `momentum'. They do not have the lower bound on the mass. We also give a positive energy argument in higher dimensions and realise that elementary fermion cannot exist in our examples.Comment: 7 pages, the version to be published in Phys. Rev.

Sound propagation in density wave conductors and the effect of long-range Coulomb interaction

We study theoretically the sound propagation in charge- and spin-density waves in the hydrodynamic regime. First, making use of the method of comoving frame, we construct the stress tensor appropriate for quasi-one dimensional systems within tight-binding approximation. Taking into account the screening effect of the long-range Coulomb interaction, we find that the increase of the sound velocity below the critical temperature is about two orders of magnitude less for longitudinal sound than for transverse one. It is shown that only the transverse sound wave with displacement vector parallel to the chain direction couples to the phason of the density wave, therefore we expect significant electromechanical effect only in this case.Comment: revtex, 14 pages (in preprint form), submitted to PR

Double-slit interference pattern from single-slit screen and its gravitational analogues

The double slit experiment (DSE) is known as an important cornerstone in the foundations of physical theories such as Quantum Mechanics and Special Relativity. A large number of different variants of it were designed and performed over the years. We perform and discuss here a new verion with the somewhat unexpected results of obtaining interference pattern from single-slit screen. This outcome, which shows that the routes of the photons through the array were changed, leads one to discuss it, using the equivalence principle, in terms of geodesics mechanics. We show using either the Brill's version of the canonical formulation of general relativity or the linearized version of it that one may find corresponding and analogous situations in the framework of general relativity.Comment: 51 pages, 12 Figures five of them contain two subfigures and thus the number of figures is 17, 1 Table. Some minor changes introduced, especially, in the reference

ADAMTS13: A New Link Between Thrombosis and Inflammation

von Willebrand factor (VWF) levels are elevated and a disintegrin-like and metalloprotease with thrombospondin type I repeats–13 (ADAMTS13) activity is decreased in both acute and chronic inflammation. We hypothesized that by cleaving hyperactive ultralarge VWF (ULVWF) multimers, ADAMTS13 down-regulates both thrombosis and inflammation. Using intravital microscopy, we show that ADAMTS13 deficiency results in increased leukocyte rolling on unstimulated veins and increased leukocyte adhesion in inflamed veins. Both processes were dependent on the presence of VWF. Depletion of platelets in $Adamts13^{−/−}$ mice reduced leukocyte rolling, suggesting that platelet interaction with ULVWF contributes to this process. Increased levels of endothelial P-selectin and plasma VWF in $Adamts13^{−/−}$ compared with wild-type (WT) mice indicated an elevated release of Weibel-Palade bodies. ULVWF multimers released upon stimulation with histamine, a secretagogue of Weibel-Palade bodies, slowed down leukocyte rolling in $Adamts13^{−/−}$ but not in WT mice. Furthermore, in inflammatory models, ADAMTS13 deficiency resulted in enhanced extravasation of neutrophils, and this process was also dependent on VWF. Our findings reveal an important role for ADAMTS13 in preventing excessive spontaneous Weibel-Palade body secretion, and in the regulation of leukocyte adhesion and extravasation during inflammation

A Cosmological Constant Limits the Size of Black Holes

In a space-time with cosmological constant $\Lambda>0$ and matter satisfying the dominant energy condition, the area of a black or white hole cannot exceed $4\pi/\Lambda$. This applies to event horizons where defined, i.e. in an asymptotically deSitter space-time, and to outer trapping horizons (cf. apparent horizons) in any space-time. The bound is attained if and only if the horizon is identical to that of the degenerate `Schwarzschild-deSitter' solution. This yields a topological restriction on the event horizon, namely that components whose total area exceeds $4\pi/\Lambda$ cannot merge. We discuss the conjectured isoperimetric inequality and implications for the cosmic censorship conjecture.Comment: 10 page

Coupling of the lattice and superlattice deformations and hysteresis in thermal expansion for the quasi one-dimensional conductor TaS3_3

An original interferometer-based setup for measurements of length of needle-like samples is developed, and thermal expansion of o-TaS$_3$ crystals is studied. Below the Peierls transition the temperature hysteresis of length $L$ is observed, the width of the hysteresis loop $\delta L/L$ being up to $5 \cdot 10^{-5}$. The behavior of the loop is anomalous: the length changes so that it is in front of its equilibrium value. The hysteresis loop couples with that of conductivity. The sign and the value of the length hysteresis are consistent with the strain dependence of the charge-density waves (CDW) wave vector. With lowering temperature down to 100 K the CDW elastic modulus grows achieving a value comparable with the lattice Young modulus. Our results could be helpful in consideration of different systems with intrinsic superstructures.Comment: 4 pages, 3 figures. Phys. Rev. Lett., accepted for publicatio

Time-symmetric initial data for binary black holes in numerical relativity

We look for physically realistic initial data in numerical relativity which are in agreement with post-Newtonian approximations. We propose a particular solution of the time-symmetric constraint equation, appropriate to two momentarily static black holes, in the form of a conformal decomposition of the spatial metric. This solution is isometric to the post-Newtonian metric up to the 2PN order. It represents a non-linear deformation of the solution of Brill and Lindquist, i.e. an asymptotically flat region is connected to two asymptotically flat (in a certain weak sense) sheets, that are the images of the two singularities through appropriate inversion transformations. The total ADM mass M as well as the individual masses m_1 and m_2 (when they exist) are computed by surface integrals performed at infinity. Using second order perturbation theory on the Brill-Lindquist background, we prove that the binary's interacting mass-energy M-m_1-m_2 is well-defined at the 2PN order and in agreement with the known post-Newtonian result.Comment: 27 pages, to appear in Phys. Rev.

On completeness of orbits of Killing vector fields

A Theorem is proved which reduces the problem of completeness of orbits of Killing vector fields in maximal globally hyperbolic, say vacuum, space--times to some properties of the orbits near the Cauchy surface. In particular it is shown that all Killing orbits are complete in maximal developements of asymptotically flat Cauchy data, or of Cauchy data prescribed on a compact manifold. This result gives a significant strengthening of the uniqueness theorems for black holes.Comment: 16 pages, Latex, preprint NSF-ITP-93-4