Electrostatic Electron Microscopy. II

This paper is a continuation of the description of problems arising in the development and design of an electrostatic electron microscope. The present article discusses depth of focus, lens and field stops, shielding, manufacturing tolerances, the choice of the number of stages of magnification, and alternative methods of viewing and recording the final image. A following paper will describe a completed instrument

Electrostatic Electron Microscopy. III

This article, the final one of a series on the design of electrostatic electron microscopes, contains a description of an instrument which illustrates the principles previously discussed. The microscope described is believed to be the first constructed with the object of providing the greatest of simplicity in construction, operation, and maintenance with the design parameters balanced to give a particular range of resolving power. The range chosen is about ten times the light microscope. The instrument is permanently aligned and utilizes external photography. The over-all size and weight of the instrument, as well as the number and complexity of components, are materially less than previously described instruments

Apollo experience report guidance and control systems: Primary guidance, navigation, and control system development

The primary guidance, navigation, and control systems for both the lunar module and the command module are described. Development of the Apollo primary guidance systems is traced from adaptation of the Polaris Mark II system through evolution from Block I to Block II configurations; the discussion includes design concepts used, test and qualification programs performed, and major problems encountered. The major subsystems (inertial, computer, and optical) are covered. Separate sections on the inertial components (gyroscopes and accelerometers) are presented because these components represent a major contribution to the success of the primary guidance, navigation, and control system

Using Electronic Drug Monitor Feedback to Improve Adherence to Antiretroviral Therapy Among HIV-Positive Patients in China

Effective antiretroviral therapy (ART) requires excellent adherence. Little is known about how to improve ART adherence in many HIV/AIDS-affected countries, including China. We therefore assessed an adherence intervention among HIV-positive patients in southwestern China. Eighty subjects were enrolled and monitored for 6 months. Sixty-eight remaining subjects were randomized to intervention/control arms. In months 7–12, intervention subjects were counseled using EDM feedback; controls continued with standard of care. Among randomized subjects, mean adherence and CD4 count were 86.8 vs. 83.8% and 297 vs. 357 cells/μl in intervention vs. control subjects, respectively. At month 12, among 64 subjects who completed the trial, mean adherence had risen significantly among intervention subjects to 96.5% but remained unchanged in controls. Mean CD4 count rose by 90 cells/μl and declined by 9 cells/μl among intervention and control subjects, respectively. EDM feedback as a counseling tool appears promising for management of HIV and other chronic diseases.Boston University and the Office of Health and Nutrition of the United States Agency for International Development (GHS-A-00-03-00030-00); World Health Organization; United States Centers for Disease Control; National Institutes of Health, National Institute of Allergy and Infectious Diseases (K23 AI 62208); Mid-Career Mentoring Award (K24 RR020300

Virginia Demonstration Project Encouraging Middle School Students in Pursuing STEM Careers

Encouraging students at all grade levels to consider pursuing a career in Science, Technology, Engineering, and Mathematics (STEM) fields i s a national focus. In 2005, the Naval Surface Warfare Center, Dahlgren Division (NSWCDD), a Department of Defense laboratory located in Da hlgren, Virginia, began work on the Virginia Demonstration Project (VDP) with the goal of increasing more student interest in STEM educatio n and pursuing STEM careers. This goal continues as the program enters its sixth year. This project has been successful through the partici pation of NSWCDD's scientists and engineers who are trained as mentor s to work in local middle school classrooms throughout the school year, As an extension of the in-class activities, several STEM summer aca demies have been conducted at NSWCDD, These academies are supported by the Navy through the VDP and the STEM Learning Module Project. These projects are part of more extensive outreach efforts offered by the National Defense Education Program (NDEP), sponsored by the Director, Defense Research and Engineering. The focus of this paper is on the types of activities conducted at the summer academy, an overview of the academy planning process, and recommendations to help support a nati onal plan of integrating modeling and simulation-based engineering and science into all grade levels. based upon the lessons learne

Operationalising and measuring language dominance

The paper offers a new way to measure language ability in bilinguals, based on measures of lexical richness. The validity of proposed approach is tested in a variety of ways