Amplifier clamping circuit for horizon scanner Patent

Clamped amplifier circuit for horizon scanner enabling amplification and accurate measurement of specified parameter

Attitude control system Patent

Development of attitude control system for spacecraft orientatio

Base composition of intact nucleic acid oligomers

Base composition of intact nucleic acid oligomer

Repetitions in the polypeptide sequence of cytochromes

Protein evolution from peptides, gene duplications and deletions in polypeptides and cytochrome

Cyclic Universe and Infinite Past

We address two questions about the past for infinitely cyclic cosmology. The first is whether it can contain an infinite length null geodesic into the past in view of the Borde-Guth-Vilenkin (BGV) "no-go" theorem, The second is whether, given that a small fraction of spawned universes fail to cycle, there is an adequate probability for a successful universe after an infinite time. We give positive answers to both questions then show that in infinite cyclicity the total number of universes has been infinite for an arbitrarily long time.Comment: 7 pages. Clarification in discussion of infinite pas

Analysis of Accordion DNA Stretching Revealed by The Gold Cluster Ruler

A promising new method for measuring intramolecular distances in solution uses small-angle X-ray scattering interference between gold nanocrystal labels (Mathew-Fenn et al, Science, 322, 446 (2008)). When applied to double stranded DNA, it revealed that the DNA length fluctuations are strikingly strong and correlated over at least 80 base pair steps. In other words, the DNA behaves as accordion bellows, with distant fragments stretching and shrinking concertedly. This hypothesis, however, disagrees with earlier experimental and computational observations. This Letter shows that the discrepancy can be rationalized by taking into account the cluster exclusion volume and assuming a moderate long-range repulsion between them. The long-range interaction can originate from an ion exclusion effect and cluster polarization in close proximity to the DNA surface.Comment: 9 pages, 4 figures, to appear in Phys. Rev.

Design of a single axis simulator for satellite control system testing and for low torque measurement

Single axis simulator design for satellite control system testing and low torque measuremen

The Impact of State Dependent Coverage Expansions on Young Adult Insurance Status: Further Analysis

Outlines how state initiatives to expand dependent coverage affected young adults' rates of uninsurance and of employer-sponsored coverage. Considers differential time effects and implications for national reform provisions to expand coverage to age 26

Stretching of a single-stranded DNA: Evidence for structural transition

Recent experiments have shown that the force-extension (F-x) curve for single-stranded DNA (ssDNA) consisting only of adenine [poly(dA)] is significantly different from thymine [poly(dT)]. Here, we show that the base stacking interaction is not sufficient to describe the F-x curves as seen in the experiments. A reduction in the reaction co-ordinate arising from the formation of helix at low forces and an increase in the distance between consecutive phosphates of unstacked bases in the stretched state at high force in the proposed model, qualitatively reproduces the experimentally observed features. The multi-step plateau in the F-x curve is a signature of structural change in ssDNA.Comment: 10 pages, 4 figure

Dependent Coverage Expansions: Estimating the Impact of Current State Policies

Presents preliminary findings on common provisions in state regulations of dependent health coverage and discusses the analytic approach to estimating the impact of state policy changes on young adults