Allergic skin rash with lamotrigine and concomitant valproate therapy - Evidence for an increased risk

Cutaneous rash is one of the commonest adverse events associated with lamotrigine. We assessed whether the risk is increased in patients receiving concomitant valproate therapy in a population of 103 adult patients with intractable epilepsy, who had lamotrigine added to their treatment. Of the 33 patients taking valproate, 10 (30%) developed a rash, whilst of the 70 not taking valproate, only 6 (8%) developed a rash. This suggests a significantly higher risk of cutaneous rash when starting lamotrigine in patients already taking valproate (p<0.02)

A methodology for selective removal of orbital debris

Earth-orbiting objects, large enough to be tracked, were surveyed for possible systematic debris removal. Based upon the statistical collision studies of others, it was determined that objects in orbits approximately 1000 km above the Earth's surface are at greatest collisional risk. Russian C-1B boosters were identified as the most important target of opportunity for debris removal. Currently, more than 100 in tact boosters are orbiting the Earth with apogees between 950 km and 1050 km. Using data provided by Energia USA, specific information on the C-1B booster, in terms of rendezvous and capture strategies, was discussed

Conceptual design of an orbital debris collector

The current Lower Earth Orbit (LEO) environment has become overly crowded with space debris. An evaluation of types of debris is presented in order to determine which debris poses the greatest threat to operation in space, and would therefore provide a feasible target for removal. A target meeting these functional requirements was found in the Cosmos C-1B Rocket Body. These launchers are spent space transporters which constitute a very grave risk of collision and fragmentation in LEO. The motion and physical characteristics of these rocket bodies have determined the most feasible method of removal. The proposed Orbital Debris Collector (ODC) device is designed to attach to the Orbital Maneuvering Vehicle (OMV), which provides all propulsion, tracking, and power systems. The OMV/ODC combination, the Rocket Body Retrieval Vehicle (RBRV), will match orbits with the rocket body, use a spin table to match the rotational motion of the debris, capture it, despin it, and remove it from orbit by allowing it to fall into the Earth's atmosphere. A disposal analysis is presented to show how the debris will be deorbited into the Earth's atmosphere. The conceptual means of operation of a sample mission is described

Roles, uses, and benefits of general aviation aircraft in aerospace engineering education

Many colleges and universities throughout the United States offer outstanding programs in aerospace engineering. In addition to the fundamentals of aerodynamics, propulsion, flight dynamics, and air vehicle design, many of the best programs have in the past provided students the opportunity to design and fly airborne experiments on board various types of aircraft. Sadly, however, the number of institutions offering such 'airborne laboratories' has dwindled in recent years. As a result, opportunities for students to apply their classroom knowledge, analytical skills, and engineering judgement to the development and management of flight experiments on an actual aircraft are indeed rare. One major reason for the elimination of flight programs by some institutions, particularly the smaller colleges, is the prohibitive cost of operating and maintaining an aircraft as a flying laboratory. The purpose of this paper is to discuss simple, low-cost, relevant flight experiments that can be performed using readily available general aviation aircraft. This paper examines flight experiments that have been successfully conducted on board the NASA Lewis Research Center's T-34B aircraft, as part of the NASA/AIAA/University Flight Experiment Program for Students (NAUFEPS) and discusses how similar experiments could be inexpensively performed on other general aviation aircraft

Simulating Brazils tax-benefit system using Brahms, the Brazilian household microsimulation model

Despite raising an amount of taxes that represents nearly 37% of the countrys GDP and spending over half of this revenue on social programmes, the Brazilian government has not been able to significantly alleviate inequality and poverty. A number of studies have shown evidence that, to a great extent, this situation is due to the inadequate targeting of public expenditures. The distributive impact of the financing of these expenditures, however, has received less attention. This paper investigates the combined impact of taxes and government cash transfers on the distribution of income among Brazilian households and compares Brazils redistributive performance with that of some countries with a similar tax burden.Apesar de arrecadar um montante de tributos equivalente a cerca de 37% do PIB e gastar mais da metade desta receita em programas sociais, o governo brasileiro não tem sido capaz de aliviar significativamente o problema da desigualdade e da pobreza. Alguns estudos têm mostrado evidência de que esta situação é, em grande parte, devida à inadequada focalização dos gastos públicos. Entretanto, o impacto distributivo do financiamento desses gastos tem recebido menos atenção. O presente trabalho investiga o impacto conjunto dos tributos e transferências monetárias governamentais sobre a distribuição de renda entre os domicílios brasileiros e compara o Brasil com alguns outros países com carga tributária semelhante

Low Gravity Guidance System for Airborne Microgravity Research

Microgravity research techniques have been established to achieve a greater understanding of the role of gravity in the fundamentals of a variety of physical phenomena and material processing. One technique in use at the NASA Lewis Research Center involves flying Keplarian trajectories with a modified Lear Jet and DC-9 aircraft to achieve a highly accurate Microgravity environment by neutralizing accelerations in all three axis of the aircraft. The Low Gravity Guidance System (LGGS) assists the pilot and copilot in flying the trajectories by displaying the aircraft acceleration data in a graphical display format. The Low Gravity Guidance System is a microprocessor based system that acquires and displays the aircraft acceleration information. This information is presented using an electroluminescent display mounted over the pilot's instrument panel. The pilot can select the Microgravity range that is required for a given research event. This paper describes the characteristics, design, calibration and testing of the Low Gravity Guidance System Phase 3, significant lessons from earlier systems and the developmental work on future systems

Piloted Evaluation of an Integrated Methodology for Propulsion and Airframe Control Design

An integrated methodology for propulsion and airframe control has been developed and evaluated for a Short Take-Off Vertical Landing (STOVL) aircraft using a fixed base flight simulator at NASA Lewis Research Center. For this evaluation the flight simulator is configured for transition flight using a STOVL aircraft model, a full nonlinear turbofan engine model, simulated cockpit and displays, and pilot effectors. The paper provides a brief description of the simulation models, the flight simulation environment, the displays and symbology, the integrated control design, and the piloted tasks used for control design evaluation. In the simulation, the pilots successfully completed typical transition phase tasks such as combined constant deceleration with flight path tracking, and constant acceleration wave-off maneuvers. The pilot comments of the integrated system performance and the display symbology are discussed and analyzed to identify potential areas of improvement

Enhancing Information Quality as Part of the Disease Surveillance System in Malawi, Africa: Reflections on a mHealth Intervention

Public health surveillance and response to disease outbreaks is still a hurdle in many developing countries across sub-Saharan Africa. Pivotal in disease surveillance and response is the reliance on valid information, hence, the need for information which has high Information Quality (IQ) characteristics. A key issue with disease surveillance systems, stem from the diverse range of data sources with various levels of information quality that may affect the trustworthiness of the information. However, with the increasing diffusion of mobile phone technologies, there are opportunities to improve IQ. The aim of this study was to assess the information quality in data collected through a smartphone application. Based on qualitative data from interviews, workshop and system specifications, it was found that information quality improves with the use of smartphone applications but aspects such as user competence and trustworthiness, must be addressed to maximize the benefits of using mobile technologies for disease surveillance

The Costs of Carnivory

Mammalian carnivores fall into two broad dietary groups: smaller carnivores (<20 kg) that feed on very small prey (invertebrates and small vertebrates) and larger carnivores (>20 kg) that specialize in feeding on large vertebrates. We develop a model that predicts the mass-related energy budgets and limits of carnivore size within these groups. We show that the transition from small to large prey can be predicted by the maximization of net energy gain; larger carnivores achieve a higher net gain rate by concentrating on large prey. However, because it requires more energy to pursue and subdue large prey, this leads to a 2-fold step increase in energy expenditure, as well as increased intake. Across all species, energy expenditure and intake both follow a three-fourths scaling with body mass. However, when each dietary group is considered individually they both display a shallower scaling. This suggests that carnivores at the upper limits of each group are constrained by intake and adopt energy conserving strategies to counter this. Given predictions of expenditure and estimates of intake, we predict a maximum carnivore mass of approximately a ton, consistent with the largest extinct species. Our approach provides a framework for understanding carnivore energetics, size, and extinction dynamics