Propellant material compatibility program and results

The effects of long-term (up to 10 years) contact of inert materials with earth-storable propellants were studied for the purpose of designing chemical propulsion system components that can be used for current as well as future planetary spacecraft. The primary experimental work, and results to date are reported. Investigations include the following propellants: hydrazine, hydrazine-hydrazine nitrate blends, monomethyl-hydrazine, and nitrogen tetroxide. Materials include: aluminum alloys, corrosion-resistant steels, and titanium alloys. More than 700 test specimen capsules were placed in long-term storage testing at 43 C in the special material compatibility facility. Material ratings relative to the 10-year requirement have been assigned

Plans for phase coherent long baseline interferometry for geophysical applications using the Anik-B communications satellite

A pilot project to establish an operational phase stable very long baseline interferometer (VLBI) for geophysical studies is described. Methods for implementation as well as practical applications are presented

Research And Development Investment

The United States has long enjoyed a leadership role in research and development investment and they invest more in both basic and applied scientific research than any other country.  The U.S. preeminence in R&D investment, however, is at a critical point.  U.S. R&D investment has been declining as a percentage of the nation’s GDP since 2009, and in 2013, U.S. R&D investment is expected to decline in real dollars as well.  Declining investment in R&D is the result of budgetary constraints and the lack of political consensus as to the economic value of the government’s continued commitment to R&D programs.  This decline in U.S. investment comes at a time when global R&D investment is increasing significantly.  Economic rivals, led by China in particular, have made investment in R&D a core component of their plans for economic growth and have committed themselves to increasing and substantial R&D investment.  U.S. policymakers need to take action now to reverse what could become a policy trend of decreased government investment in R&D, which has both a short-term and long-term impact.  R&D spending is an “economic and employment driver” and ultimately employs 8.27 million U.S. workers, generating $1.238 trillion dollars to the U.S. economy.  In addition, government investment funds the majority of basic scientific research which, in the past, has led to such innovations as digital recording technology, communication satellites, global positioning systems (GPS), and the Internet.  It is unclear if the private sector alone can make up the difference in government R&D investment.  If the U.S. fails to protect its leadership position in R&D investment, it consequently risks its leadership in science, technology, productivity, and innovation which is the basis of the nation’s employment and economic activity

Serum sIL-6Rα Predicts Impairments in Cutaneous Nitric Oxide-Dependent Vasodilation in Humans

Please view abstract in the attached PDF file

Stochastic Feedback and the Regulation of Biological Rhythms

We propose a general approach to the question of how biological rhythms spontaneously self-regulate, based on the concept of ``stochastic feedback''. We illustrate this approach by considering the neuroautonomic regulation of the heart rate. The model generates complex dynamics and successfully accounts for key characteristics of cardiac variability, including the $1/f$ power spectrum, the functional form and scaling of the distribution of variations, and correlations in the Fourier phases. Our results suggest that in healthy systems the control mechanisms operate to drive the system away from extreme values while not allowing it to settle down to a constant output.Comment: 15 pages, latex2e using rotate and epsf, with 4 ps figures. Submitted to PR

AGC 226067: A possible interacting low-mass system

We present Arecibo, GBT, VLA and WIYN/pODI observations of the ALFALFA source AGC 226067. Originally identified as an ultra-compact high velocity cloud and candidate Local Group galaxy, AGC 226067 is spatially and kinematically coincident with the Virgo cluster, and the identification by multiple groups of an optical counterpart with no resolved stars supports the interpretation that this systems lies at the Virgo distance (D=17 Mpc). The combined observations reveal that the system consists of multiple components: a central HI source associated with the optical counterpart (AGC 226067), a smaller HI-only component (AGC 229490), a second optical component (AGC 229491), and extended low surface brightness HI. Only ~1/4 of the single-dish HI emission is associated with AGC 226067; as a result, we find M_HI/L_g ~ 6 Msun/Lsun, which is lower than previous work. At D=17 Mpc, AGC 226067 has an HI mass of 1.5 x 10^7 Msun and L_g = 2.4 x 10^6 Lsun, AGC 229490 (the HI-only component) has M_HI = 3.6 x 10^6 Msun, and AGC 229491 (the second optical component) has L_g = 3.6 x 10^5 Lsun. The nature of this system of three sources is uncertain: AGC 226067 and AGC 229490 may be connected by an HI bridge, and AGC 229490 and AGC 229491 are separated by only 0.5'. The current data do not resolve the HI in AGC 229490 and its origin is unclear. We discuss possible scenarios for this system of objects: an interacting system of dwarf galaxies, accretion of material onto AGC 226067, or stripping of material from AGC 226067.Comment: Accepted for publication in A&A. 6 pages, 4 figure

Preparation for Full Time Employment: A Capstone Experience for Students in Leadership Programs

This practice paper describes the development and implementation of a senior capstone course for communication and leadership development for undergraduate students. The resulting course is a unique combination of experiential skill development and career preparation. The success of this course provides students with an important and meaningful culmination of their undergraduate experiences

Preparation for Full Time Employment: A Capstone Experience for Students in Leadership Programs

This practice paper describes the development and implementation of a senior capstone course for communication and leadership development for undergraduate students. The resulting course is a unique combination of experiential skill development and career preparation. The success of this course provides students with an important and meaningful culmination of their undergraduate experiences

A Planetary Mass Companion to the K0 Giant HD 17092

We report the discovery of a substellar-mass companion to the K0-giant HD 17092 with the Hobby-Eberly Telescope. In the absence of any correlation of the observed 360-day periodicity with the standard indicators of stellar activity, the observed radial velocity variations are most plausibly explained in terms of a Keplerian motion of a planetary-mass body around the star. With the estimated stellar mass of 2.3Msun, the minimum mass of the planet is 4.6MJ. The planet's orbit is characterized by a mild eccentricity of e=0.17 and a semi-major axis of 1.3 AU. This is the tenth published detection of a planetary companion around a red giant star. Such discoveries add to our understanding of planet formation around intermediate-mass stars and they provide dynamical information on the evolution of planetary systems around post-main sequence stars.Comment: 13 pages, 3 figures, 2 tables. Submitted to Ap