Jigsaw: investigative analysis on text document collections through visualization

This article describes the Jigsaw system for helping investigative analysis across collections of text documents. Jigsaw provides multiple visualizations of the documents and the entities within them to help investigators discern embedded stories and plots. Our early focus within Jigsaw has not been on legal documents and E-discovery, but we feel that the system may have potential in these areas as well. This article illustrates Jigsaw’s views and operations using Enron email archives as example documents

The Creative Link: Creativity, Resilience, Connection and Story

This study examines the intersection between the theories of Campbell\u27s \u27The Hero\u27sJourney,\u27 Brown\u27s \u27Rising Strong,\u27 and Catmull\u27s \u27Creativity, Inc..\u27 and the experiences of various photographers who have undertaken projects on motherhood. Using a mixed-methods approach, the study analyzes books, interviews, blog entries, documentaries, articles and artist statements to identify patterns and themes. The study finds a consistent pattern of challenge, risk, vulnerability, and struggle, resulting in growth and connection. It concludes the creative process has parallels to patterns of resilience and the narrative arc and can facilitate connection with self and others. By recognizing this pattern in a variety of spheres we can be more aware, intentional, and hopeful about our personal outcomes

Defining the Role of Reactive Oxygen Species, Nitric Oxide, and Sphingolipid Signaling in Tumor Necrosis Factor - Induced Skeletal Muscle Weakness

In many chronic inflammatory diseases, patients suffer from skeletal muscle weakness, exacerbating their symptoms. Serum levels of tumor necrosis factor-alpha (TNF) and sphingomyelinase are increased, suggesting their possible role in the progression of this weakness. This dissertation focuses on the role that reactive oxygen species (ROS) and nitric oxide (NO) play in mediating TNF-induced skeletal muscle weakness and to what extent sphingolipid signaling mediates cellular response to TNF. The first aim of this work was to identify which endogenous oxidant species stimulated by TNF contributes to skeletal muscle weakness. In C57BL/6 mice (n=38), intraperitoneal injection of TNF elicited a 25% depression of diaphragm contractile function. In separate experiments, diaphragm fiber bundles harvested from mice (n=39) and treated with TNF ex vivo showed a 38% depression of contractile function compared to untreated controls. Using ROS and NO-sensitive fluorescence microscopy in parallel with a genetic knockout animal model, TNF-induced contractile dysfunction was found to be mediated by NO generated by a specific isoform of nitric oxide synthase (NOS), nNOS. Basal levels of ROS were necessary co-mediators, but were not sufficient to elicit TNF-induced diaphragm weakness. The second aim of this dissertation was to investigate the extent to which sphingolipids could serve as a signaling cascade post-TNF stimulus leading to the generation of NO in skeletal muscle. The effects of TNF exposure in C2C12 skeletal muscle cells were studied in vitro using mass spectroscopy to measure sphingolipid metabolism and fluorescent microscopy to quantify oxidant production. TNF exposure was associated with significant mean increases in sphingosine (+52%), general oxidant activity (+33%), and NO production (+14%). These increases were due to specific modulation of nNOS as demonstrated by siRNA knockdown of neutral ceramidase and nNOS, and confirmed by pharmacologic inhibition using N-Oleoylethanolamine and di-methylsphingosine. In summary, these findings confirm NO as a major causative oxidant contributing to TNF’s deleterious phenotype in skeletal muscle. Moreover, the work suggests a new role for sphingosine in skeletal muscle and warrants further study of the enzymatic regulation of sphingosine to advance the discovery of new therapies for patients suffering from chronic inflammation

Radio broadcasting as used by Jehovah's Witnesses

Thesis (M.S.)--Boston Universit

A trajectory optimization and rendezvous study of a manned Mars ascent vehicle

The purpose of this study is to describe the ascent flight dynamics and orbital maneuvering requirements of a manned Mars Ascent Vehicle (MAY) within the missionstructure defined by the NASA Design Reference Mission (DRM). The primary task of the MAV is to transport the astronauts and their scientific cargo from the surface of Marsto an orbiting Earth Return Vehicle (ERY), in which the crew will depart Mars orbit and begin their return to Earth. This objective comprises two phases of operation, an ascent from the Martian surface to a parking orbit, and an orbital rendezvous with the waiting ERY, and is critical to the success of a manned Mars mission.In order to accomplish this study two programs were written to model each of the distinct phases of MAV operation. The ascent program uses Pontryagin\u27s MaximumPrinciple to optimize the ascent trajectory and reduce it to a two point boundary value problem. This is then solved by the numerical method of Runge-Kutta integration, withNewton\u27s Method used to guess the unknown initial conditions of the trajectory. Thisprogram finds the optimal trajectory to place the MAY into a parking orbit prior to rendezvous with the ERY, minimizing propellant expended and maximizing useful spacecraft payload.The orbital rendezvous portion of the study involves quantifying the impulsive maneuvers needed to alter the MAY orbit to match its position and velocity with the ERY. This is accomplished through a study of the differential equations of relative position and velocity between the two vehicles. The resulting boundary value problem is solved using the numerical methods of Runge-Kutta integration and Newton\u27s Method,providing the necessary maneuvers to achieve orbital rendezvous

A Dynamic Study of an Earth Orbiting Tether Propulsion System

Commercial expansion beyond Earth orbit demands efficient, low cost and regular access to space that is not given by current launch systems. An alternative to rocketry has been proposed in the use of tethers as a method of in-space propulsion. One possible implementation of tether propulsion involves the use of a long, vertically oriented tether orbiting the Earth. A suborbital launch vehicle will deliver a payload to the tether’s lower tip, which will then be carried up its length by an elevator car to the upper tip, where the payload is released on a transfer orbit. The orbiting space elevator represents a reusable second stage of a launch system designed to place payloads in high Earth orbit or trans-lunar trajectories. This study investigates several dynamics problems encountered in an Earth orbiting tether propulsion system. In addition to calculating the structural requirements for the tether to safely bear the payload mass, several analytical estimation methods of the tether’s orbital response to loading have been developed and compared to previous studies. A detailed mathematical simulation of the tether’s orbital stability has been created, accounting for natural perturbations to the tether’s orbit. With the dynamic simulation of the elevator’s orbit, predictions of the total tether mass required to handle a payload with out degrading its orbit have been quantified. The performance required by the suborbital launch vehicle’s operation has also been examined. Minimum propellant trajectories to the elevator’s lower tip are found using a Hamiltonian based trajectory optimization routine. The launch vehicle maneuvering requirements needed for rendezvous with the orbiting elevator have also been explored. The margins of performance needed for a launch vehicle to deliver a payload to the elevator lower tip have been calculated to be roughly equivalent to a single stage to orbit mission profile. The usefulness of the tether within the context of a trans-lunar transportation system has also been investigated. It has been shown that elevator-based transit to the Moon offers significant savings in Δv over a traditional rocket-based transportation scheme

HotSketch: Drawing Police Patrol Routes among Spatiotemporal Crime Hotspots

During the course of a day, a police unit is expected to move throughout the city to provide a visible presence and respond quickly to emergencies. Planning this movement at the beginning of the shift can provide a helpful first step in ensuring that officers are present in areas of high crime, but these plans can quickly break down as they are pulled away to 911 calls. Once such an initial plan is deferred, police units need to be able to rapidly and fluidly decide where to go next depending on their immediate location and time. In this paper, we present our research to couple spatiotemporal analysis of historical crime data with sketch-based interaction methods. This research is presented through an initial prototype, HotSketch, which we describe through a set of use cases within the domain of police patrol route planning