Dust in stellar wind bow shocks

A number of high velocity O stars have associated parsec-sized structure visible in the IRAS infrared. They can most readily be explained as the dense shells of stellar wind bow shocks. The IR emission arises from starlight-heated post-shock dust, and possibly also from ionic lines. Emission from pre-shock dust is often seen as well, and allows in principle the empirical determination of the effects of shocks on dust. Since the observed bow shocks span a range of velocities a comparison with theories for shock destruction of dust is possible

Synthesis of terephthalonitrile N,N-dioxide

The preparation is described of terephthalonitrile N,N prime-dioxide by the chlorination of terephthalaldehyde dioxime to yield terephthalohydroximol chloride, to which absolute methynol was added to yield the TPNO

The levels of edit, second edition

The editorial process is analyzed, and five levels of edit are identified. These levels represent cumulative combinations of nine types of edit: Coordination, Policy, Integrity, Screening, Copy Clarification, Format, Mechanical Style, Language, and Substantive. The levels and types of edit, although developed for specific use with external reports at the Jet Propulsion Laboratory, cover the general range of technical editing, especially as it applies to an in-house technical publications organization. Each type of edit is set forth in terms of groups of actions to be performed by editor. The edit-level concept has enhanced understanding and communication among editors, authors, and publications managers concerning the specific editorial work to be done on each manuscript. It has also proved useful as a management tool for estimating and monitoring cost

Graphical microcode simulator with a reconfigurable datapath

Microcode is a symbolic way to simplify control design that allows changing, testing and updating the control unit of processors. By changing the microcode, the same datapath can be used for an entirely different application, such as supporting a completely different instruction set. For these reasons, a majority of control units in modern day processors are microcoded. The object was to investigate and implement a graphical microcode simulator with a reconfigurable datapath and microcode format. By allowing a wide configuration of the datapath, many types of logical processors can be designed and simulated. The resulting implemented simulator is able to fill the void in microprogramming tools since there are no graphical microcode simulators that allow such customization of the datapath. The customization of the datapath goes beyond allowing different files specifying the datapath, it allows the datapath to be created and modified using the graphical interface.This tool is able to be used to design and simulate general-purpose processors and application specific processors through datapath and microcode configurations. In the academic setting, this tool provides easier microcode testing through verification on the instruction level for instructors and provide simulation debugging through code tracing and breakpoints for students

Trajectory optimization and guidance for an aerospace plane

The first step in the approach to developing guidance laws for a horizontal take-off, air breathing single-stage-to-orbit vehicle is to characterize the minimum-fuel ascent trajectories. The capability to generate constrained, minimum fuel ascent trajectories for a single-stage-to-orbit vehicle was developed. A key component of this capability is the general purpose trajectory optimization program OTIS. The pre-production version, OTIS 0.96 was installed and run on a Convex C-1. A propulsion model was developed covering the entire flight envelope of a single-stage-to-orbit vehicle. Three separate propulsion modes, corresponding to an after burning turbojet, a ramjet and a scramjet, are used in the air breathing propulsion phase. The Generic Hypersonic Aerodynamic Model Example aerodynamic model of a hypersonic air breathing single-stage-to-orbit vehicle was obtained and implemented. Preliminary results pertaining to the effects of variations in acceleration constraints, available thrust level and fuel specific impulse on the shape of the minimum-fuel ascent trajectories were obtained. The results show that, if the air breathing engines are sized for acceleration to orbital velocity, it is the acceleration constraint rather than the dynamic pressure constraint that is active during ascent

The Ineffective Assistance of Counsel Quandry: The Debate Continues Strickland v. Washington

In recent years, dissatisfied criminal defendants have increasingly resorted to claims alleging actual ineffectiveness of counsel as a vehicle for challenging their convictions. Prior to Strickland v. Washington, the Supreme Court had not delineated the proper standards for reviewing claims of actual ineffectiveness of counsel. The lack of a national standard for assessing defense counsel\u27s performance, as it relates to the constitutional requirement, generated extensive deliberation by lower courts and commentators. Faced with a deluge of actual ineffectiveness claims, the lower courts were forced to formulate standards to distinguish effective from ineffective assistance. However, the ensuing diverse standards employed by the courts resulted in an unjust jurisdictional discrepancy in the adjudication of those claims. This ad hoc treatment demonstrated the exigence for a resolution of these conflicting standards. In order to rectify the problematic situation confronting the criminal judicial system, the Supreme Court in Strickland espoused homogeneous standards for judging a criminal defendant\u27s contention that the Constitution mandates reversing a conviction because of actual ineffectiveness of counsel at the trial or sentencing phase

Disulfide Bridging the Gap between Src and Cortactin: A New Paradigm in SH2 Domain-mediated Signaling

Src and cortactin are cytoplasmic proteins that are implicated in cancer progression and metastasis. Src is a non-receptor tyrosine kinase that also regulates normal cell homeostasis through phosphorylation of multiple downstream substrates. Cortactin is an actin binding protein and nucleation promoting factor that promotes the formation of stable branching networks within the actin cytoskeleton. Together, these proteins work in concert to promote the invasive and metastatic potential of tumor cells due to tyrosine phosphorylation of cortactin by Src. However, the mechanistic details of the interaction between Src and cortactin have never been elucidated. Collectively, this work aims to define how Src and cortactin interact to drive tumor cell invasion. The first study examines the mechanism of interaction between Src and cortactin, whereby the Src SH2 domain interacts with cortactin via a disulfide bond formation and that this binding event is necessary for the formation of pro-invasive invadopodia. The work here also defines a paradigm shift in how SH2 domain-containing proteins interact with reciprocal binding partners. The second study characterizes potential structural changes in cortactin resultant from phosphorylation by extracellular regulated protein kinases (ERKs) in order to gain structural insight into how cortactin conformation is regulated downstream of growth factor-mediated signaling events. The final study focuses on the creation of cortactin biosensor to directly monitor changes in cortactin conformation using FRET-based imaging. Taken together, these studies provide novel insights into the molecular events involved in regulating invasive tumor cell signal transduction and overall control of cortical actin dynamics during tumor metastasis