The dynamic effects of internal robots on Space Station Freedom

Many of the planned experiments of the Space Station Freedom (SSF) will require acceleration levels to be no greater than microgravity (10 exp -6 g) levels for long periods of time. Studies have demonstrated that without adequate control, routine operations may cause disturbances which are large enough to affect on-board experiments. One way to both minimize disturbances and make the SSF more autonomous is to utilize robots instead of astronauts for some operations. The present study addresses the feasibility of using robots for microgravity manipulation. Two methods for minimizing the dynamic disturbances resulting from the robot motions are evaluated. The first method is to use a robot with kinematic redundancy (redundant links). The second method involves the use of a vibration isolation device between the robot and the SSF laboratory module. The results from these methods are presented along with simulations of robots without disturbance control

Reaction-compensation technology for microgravity laboratory robots

Robots operating in the microgravity environment of an orbiting laboratory should be capable of manipulating payloads such that the motion of the robot does not disturb adjacent experiments. The current results of a NASA Lewis Research Center technology program to develop smooth, reaction-compensated manipulation based on both mechanism technology and trajectory planning strategies are present. Experimental validation of methods to reduce robot base reactions through the use of redundant degrees of freedom is discussed. Merits of smooth operation roller-driven robot joints for microgravity manipulators are also reviewed

Conversion of amino-acid sequence in proteins to classical music: search for auditory patterns

How to make music from the genome

Skeletal muscle phenotypes initiated by ectopic MyoD in transgenic mouse heart

Forced expression of the myogenic regulatory gene MyoD in many types of cultured cells initiates their conversion into skeletal muscle. It is not known, however, if MyoD expression serves to activate all or part of the skeletal muscle program in vivo during animal development, nor is it known how limiting the influences of cellular environment may be on the regulatory effects of MyoD. To begin to address these issues, we have produced transgenic mice which express MyoD in developing heart, where neither MyoD nor its three close relatives—myogenin, Myf-5, and MRF4/herculin/Myf-6—are normally expressed. The resulting gross phenotype in offspring from multiple, independent transgenic founders includes abnormal heart morphology and ultimately leads to death. At the molecular level, affected hearts exhibit activation of skeletal muscle-specific regulatory as well as structural genes. We conclude that MyoD is able to initiate the program that leads to skeletal muscle differentiation during mouse development, even in the presence of the ongoing cardiac differentiation program. Thus, targeted misexpression of this tissue-specific regulator during mammalian embryogenesis can activate, either directly or indirectly, a diverse set of genes normally restricted to a different cell lineage and a different cellular environment

Late-glacial marine invertebrate macrofossils from Point Lepreau, New Brunswick

A late-glacial shell fauna from Point Lepreau, New Brunswick produced a radiocarbon date of 13,500 years B.P. The assemblage contained well-preserved subarctic to boreal molluscs and barnacles typical of late Pleistocene marine deposits from the region. Rare specimens of sea urchin, crab and brittlestar may be the oldest recorded occurrence of these animals in the late-glacial Bay of Fundy. The assemblage fits into a previously defined Zone 3, late-glacial marine invertebrate assemblage in the Bay of Fundy-Gulf of Maine region, characterized as a Diverse Arctic assemblage. RÉSUMÉ La datation par le radiocarbone a situé à 13 500 ans BP une faune invertébéie tardiglaciaire de la pointe Lepreau, ou Nouveau-Brunswick. L'assemblage renferme des mollusques et des bernacles subarctiques à boréaux bien conservés caractéristiques des dépôts marins du Pléistocène tardif de la région. Les spècimens rares d'oursins, de crabes et d'ophiures pourraient constituer les manifestations les plus anciennes de la présence de ces animaux relevées dans la région tardiglaciaire de la baie de Fundy. L'assemblage se situé à l’intérieur de l'assemblage d'invertébrés marins tardiglaciaires de la zone 3 antérieurement défini dans la région de la baie de Fundy et du golfe du Maine, caractérisé en tant qu'assemblage arctique hétéiogene. [Traduit par la rédaction

Preparing for the Pacific Century: Fostering Technology Transfer in Southeast Asia

This article discusses a number of considerations that are central to structuring a successful technology transfer or investment in Southeast Asia. Most of the discussion examines these considerations from the perspective of an MNC that is a potential technology transferor, investor, or vendor in the region. However, this article should also be of interest to those responsible for formulating government policies to encourage technology transfer, since it is important to do so with the MNC\u27s perspective in mind. Clearly, for a technology transfer to be successful over the long term, a balance must be achieved between the goals of the Southeast Asian nation in attracting foreign investment and technology, and the need of the MNC to profit from and protect its investment and technology