Space shuttle wing leading edge heating environment prediction derived from development flight data

An analytical program is in progress at Rockwell International to revise wing leading edge heating predictions in order to improve correlation with STS-1 to -5 flight radiometer data. This paper discusses the methods that have been used to improve agreement between prediction and flight and summarizes the aerodynamic correlations which, when updated, will be used to analyze future orbiter missions

CIVIL PRACTICE Asbestos: Provide Specific Action for Injury to Real Property for a Limited Time

The Act creates a cause of action against manufacturers or suppliers of asbestos for damage to real property. It also extends the statute of limitations for bringing such actions to July 1, 1990 but bars commencement of claims after that date

Current-induced torques due to compensated antiferromagnets

We analyse the influence of current induced torques on the magnetization configuration of a ferromagnet in a circuit containing a compensated antiferromagnet. We argue that these torques are generically non-zero and support this conclusion with a microscopic NEGF calculation for a circuit containing antiferromagnetic NiMn and ferromagnetic Co layers. Because of symmetry dictated differences in the form of the current-induced torque, the phase diagram which expresses the dependence of ferromagnet configuration on current and external magnetic field differs qualitatively from its ferromagnet-only counterpart.Comment: 4 pages, 5 figure

MOTOR VEHICLES AND TRAFFIC Motor Vehicles: Ban Obscene Bumper Stickers

The Act defines a new misdemeanor which prohibits a person from knowingly affixing or attaching an obscene bumper sticker to any motor vehicle that a person owns, operates, or uses

Evidence - Admissibility of Expert Opinion

The North Carolina Supreme Court made significant progress toward resolving the uncertainty in the law on the admissibility of medical expert opinion evidence in State v. Wade. Since State v. David, the rule in North Carolina was that an expert must base his opinion testimony on either (1) personal knowledge or observation or (2) a hypothetical question addressed to him, in which the pertinent facts are assumed to be true, or rather, assumed to be so found by the jury. After David several cases were decided which liberalized the rule considerably while others held fast to David. Without having overruled or reconciled any of these cases, the Court appeared to have a convenient precedent for the next decision, whatever its tenor may be. The next decision, which fell in line with and clarified the line of cases which more liberally allowed admission of expert opinion evidence, was Wade. The Court held that a medical expert may testify to the information on which he based his opinion, even though obtained from the patient himself, provided the information is inherently reliable

Topology Optimization of Engine Exhaust-Washed Structures

Aircraft structure subjected to elevated temperature and acoustic loading present a challenging design environment. Thermal stress in a structural component has typically been alleviated by allowing thermal expansion. However, very little work has been done which directly addresses the situation where such a prescription is not possible. When a structural component has failed due to thermally-induced tensile stresses, the answer to the question of how best to stiffen the structure is far from trivial. In this work, we demonstrate that conventional stiffening techniques, for example, those which add material to the thickness of a failing panel, may actually increase the rate of damage as well as increasing load into sub- and surrounding structure. The typical compliance minimization topology optimization formulation is applied to a thermally-loaded panel resulting in extremely non-optimal configurations. To generate successful thermal stress designs where the objectives are to lower the tensile stresses while simultaneously limiting the amount of additional load into sub- and surrounding structures, a well-known characteristic of topology optimization for a single-load case mechanical loading is exploited which by construction limits additional load into surrounding structure. Acoustic loading is also a major concern as exhaust gases with random frequency content impinge on aircraft structure in the vicinity of the engines. An evolutionary structural optimization algorithm is developed which addresses both the maximum von-Mises stress and minimum natural frequency for a generic thermal protection system. The similarities between the two approaches are demonstrated

Dramatic expansion of the black widow toxin arsenal uncovered by multi-tissue transcriptomics and venom proteomics.

BackgroundAnimal venoms attract enormous interest given their potential for pharmacological discovery and understanding the evolution of natural chemistries. Next-generation transcriptomics and proteomics provide unparalleled, but underexploited, capabilities for venom characterization. We combined multi-tissue RNA-Seq with mass spectrometry and bioinformatic analyses to determine venom gland specific transcripts and venom proteins from the Western black widow spider (Latrodectus hesperus) and investigated their evolution.ResultsWe estimated expression of 97,217 L. hesperus transcripts in venom glands relative to silk and cephalothorax tissues. We identified 695 venom gland specific transcripts (VSTs), many of which BLAST and GO term analyses indicate may function as toxins or their delivery agents. ~38% of VSTs had BLAST hits, including latrotoxins, inhibitor cystine knot toxins, CRISPs, hyaluronidases, chitinase, and proteases, and 59% of VSTs had predicted protein domains. Latrotoxins are venom toxins that cause massive neurotransmitter release from vertebrate or invertebrate neurons. We discovered ≥ 20 divergent latrotoxin paralogs expressed in L. hesperus venom glands, significantly increasing this biomedically important family. Mass spectrometry of L. hesperus venom identified 49 proteins from VSTs, 24 of which BLAST to toxins. Phylogenetic analyses showed venom gland specific gene family expansions and shifts in tissue expression.ConclusionsQuantitative expression analyses comparing multiple tissues are necessary to identify venom gland specific transcripts. We present a black widow venom specific exome that uncovers a trove of diverse toxins and associated proteins, suggesting a dynamic evolutionary history. This justifies a reevaluation of the functional activities of black widow venom in light of its emerging complexity

Current Induced Order Parameter Dynamics: Microscopic Theory Applied to Co/Cu/Co spin valves

Transport currents can alter alter order parameter dynamics and change steady states in superconductors, in ferromagnets, and in hybrid systems. In this article we present a scheme for fully microscopic evaluation of order parameter dynamics that is intended for application to nanoscale systems. The approach relies on time-dependent mean-field-theory, on an adiabatic approximation, and on the use of non-equilibrium Greens function (NEGF) theory to calculate the influence of a bias voltage across a system on its steady-state density matrix. We apply this scheme to examine the spin-transfer torques which drive magnetization dynamics in Co/Cu/Co spin-valve structures. Our microscopic torques are peaked near Co/Cu interfaces, in agreement with most previous pictures, but suprisingly act mainly on Co transition metal $d$-orbitals rather than on $s$-orbitals as generally supposed.Comment: 9 pages, 5 figure

Exploring the Determinants of ‘Best Practice’ in Network Regulation: The Case of the Electricity Sector

In this paper we use a best practice index constructed from the survey responses of regulators in 40 countries to explore the determinants of outcomes in electricity network regulation. We construct a model of explained behaviour where we are particularly interested in understanding the impact of industry setting, political, and economic environments on the degree of best practice regulation. Our results suggest that political and economic institutions as well as the behaviour of regulators in neighbouring countries/states may be important determinants of outcomes; this also leads us to question whether one “best practice” model is in fact applicable to countries with very different political and economic contexts