Using and Distributing Spaceflight Data: The Johnson Space Center Life Sciences Data Archive

Life sciences data collected before, during and after spaceflight are valuable and often irreplaceable. The Johnson Space Center Life is hard to find, and much of the data (e.g. Sciences Data Archive has been designed to provide researchers, engineers, managers and educators interactive access to information about and data from human spaceflight experiments. The archive system consists of a Data Acquisition System, Database Management System, CD-ROM Mastering System and Catalog Information System (CIS). The catalog information system is the heart of the archive. The CIS provides detailed experiment descriptions (both written and as QuickTime movies), hardware descriptions, hardware images, documents, and data. An initial evaluation of the archive at a scientific meeting showed that 88% of those who evaluated the catalog want to use the system when completed. The majority of the evaluators found the archive flexible, satisfying and easy to use. We conclude that the data archive effectively provides key life sciences data to interested users

Tubulin response to intense nanosecond-scale electric field in molecular dynamics simulation

Intense pulsed electric fields are known to act at the cell membrane level and are already being exploited in biomedical and biotechnological applications. However, it is not clear if electric pulses within biomedically-attainable parameters could directly influence intra-cellular components such as cytoskeletal proteins. If so, a molecular mechanism of action could be uncovered for therapeutic applications of such electric fields. To help clarify this question, we first identified that a tubulin heterodimer is a natural biological target for intense electric fields due to its exceptional electric properties and crucial roles played in cell division. Using molecular dynamics simulations, we then demonstrated that an intense - yet experimentally attainable - electric field of nanosecond duration can affect the bβ-tubulin’s C-terminus conformations and also influence local electrostatic properties at the GTPase as well as the binding sites of major tubulin drugs site. Our results suggest that intense nanosecond electric pulses could be used for physical modulation of microtubule dynamics. Since a nanosecond pulsed electric field can penetrate the tissues and cellular membranes due to its broadband spectrum, our results are also potentially significant for the development of new therapeutic protocols

On the Right Track? Investigating the Effect of Path Characteristics on Visuospatial Bootstrapping in Verbal Serial Recall

Visuospatial bootstrapping (VSB) occurs when memory for verbal material is enhanced via association with meaningful visuospatial information. Sequences of digits are visually presented either in the center of the screen or within a keypad layout in which the digits may be arranged identically to familiar pin pad and mobile phone layouts, or randomly. Recall is consistently higher when digits are presented in the familiar layout. This “bootstrapping” could involve primarily long-term knowledge of the layout, primarily short-term memory of the unique spatial path, or may depend on both. We manipulated the path complexity of sequences to test whether the VSB effect depends on the quality of spatial representations in conjunction with the familiarity of the spatial layout in two experiments. We consistently observed both VSB effects and path complexity effects on verbal serial recall, but never observed any interaction between these factors, even when articulatory suppression was imposed. Analysis of recall by serial position revealed that the VSB effect was focused on the end-of-list items. Our finding of pervasive path complexity effects on verbal serial recall suggests incidental encoding of spatial path occurs during visually-presented verbal tasks regardless of layout familiarity, confirming that spatial factors can affect verbal recall, but ruling out the notion that incidental spatial paths are uniquely and voluntarily encoded with familiar layouts

Who am I? Autobiographical retrieval improves access to self-concepts

It is considered that an individual's current self-concept plays a crucial role in guiding the retrieval of autobiographical memory. Using a novel fluency paradigm, the present research examined whether or not the reverse is also true, that is, does memory retrieval influence the description of the conceptual self? Specifically, this study examined the effect of prior autobiographical reverie on the subsequent retrieval of stored self-concepts. Participants wrote a description of a personally relevant memory or a control topic (of no relevance to the self), following which they had 60 seconds to generate as many self-defining statements as possible, each beginning with I am. Participants engaging in autobiographical retrieval generated significantly more statements than those in the control condition, suggesting that autobiographical retrieval increased access to self-concepts. Type of statement also varied according to group. Participants in the autobiographical memory condition were more likely to conceptualise themselves in relation to their psychological traits, and this was replicated in a second experiment conducted online. Findings support the idea that self and episodic memory are highly related constructs, and are discussed in relation to implications for individuals with autobiographical memory deficits

Evolution of avalanche conducting states in electrorheological liquids

Charge transport in electrorheological fluids is studied experimentally under strongly nonequlibrium conditions. By injecting an electrical current into a suspension of conducting nanoparticles we are able to initiate a process of self-organization which leads, in certain cases, to formation of a stable pattern which consists of continuous conducting chains of particles. The evolution of the dissipative state in such system is a complex process. It starts as an avalanche process characterized by nucleation, growth, and thermal destruction of such dissipative elements as continuous conducting chains of particles as well as electroconvective vortices. A power-law distribution of avalanche sizes and durations, observed at this stage of the evolution, indicates that the system is in a self-organized critical state. A sharp transition into an avalanche-free state with a stable pattern of conducting chains is observed when the power dissipated in the fluid reaches its maximum. We propose a simple evolution model which obeys the maximum power condition and also shows a power-law distribution of the avalanche sizes.Comment: 15 pages, 6 figure