The growth of plant embryos in vitro. Preliminary experiments on the role of accessory substances

The aseptic culture of plant embryos isolated from the seed dates back to the work of Brown and Morris,(1) Hannig(2) and Dietrich.(3) More recent contributions to our knowledge concerning the culture in vitro of excised embryos have been made by Tukey,(4) Brunner(5) and LaRue,(6) among others. It has been recognized by, for example, Ray(7) that the embryo culture technique offers a useful tool for biochemical investigations, and it has also been recognized(4,8) that it may be used as a practical measure to circumvent the abortion of embryos. It has, however, been found that in general the growth of the excised embryo, even upon a medium containing essential inorganic materials and sugar, is far less than that of normal intact seedlings. This has led to the suggestion(5) that "accessory growth factors" which are needed in minute amounts, are required by the developing plant as they are by the developing animal organism. The present work, as well as that of Kogl and Haagen-Smit,(9) furnish final proof that this is the case; that these accessory substances, although normally furnished by the seed, may be replaced to some extent by pure compounds added in small amounts to the embryo culture medium. These investigations, taken up early in 1936, are concerned particularly with orienting experiments undertaken with an ultimate view toward the elucidation of the nature and mode of action of these accessory growth factors. The embryo culture technique is here to be used as a tool in the "hormonal" analysis of plant development

Robotic planner expert system (RPLANES)

The Artificial Intelligence Section of the Mission Planning and Analysis of the Johnson Space Center has developed a prototype of an expert system for robotic planning. A robot is given a high level goal to perform an action (i.e., swap, adjust, or stow) on a component unit of an object such as a satellite and the Robotic Planner Expert System (RPLANES) generates the necessary goals for arm actions. RPLANES is designed using the Inference Corp. Automated Reasoning Tool (ART) development tool. It resides on a SYMBOLICS 3670. RPLANES and its evolution are described

Case study: Duchy College Organic Studies Centre

This report was presented at the UK Organic Research 2002 Conference. Coswinsawsin Organic Demonstration Farm supports a stockless vegetable and cereal rotation and achieved organic status in January 2001. Over 18 months 430 people attended 18 organic farming events. Work included trials and demonstration plots, monitoring of small mammal and bird populations and a green waste composting project which are ongoing. £972,199 Objective 1 funding was awarded to expand activity across all sectors of production and establish the Organic Studies Centre at Duchy College. The project will link organic research to demonstration, technology transfer and training. The emphasis will be on farmer participation and research will be taken onto commercial farms. 82% of respondents to a farmer survey were interested in participation in organic trials and demonstration. It is anticipated that dissemination of up to date information at farm level will improve competitiveness and financial viability of farm businesses

In-home and remote use of robotic body surrogates by people with profound motor deficits

By controlling robots comparable to the human body, people with profound motor deficits could potentially perform a variety of physical tasks for themselves, improving their quality of life. The extent to which this is achievable has been unclear due to the lack of suitable interfaces by which to control robotic body surrogates and a dearth of studies involving substantial numbers of people with profound motor deficits. We developed a novel, web-based augmented reality interface that enables people with profound motor deficits to remotely control a PR2 mobile manipulator from Willow Garage, which is a human-scale, wheeled robot with two arms. We then conducted two studies to investigate the use of robotic body surrogates. In the first study, 15 novice users with profound motor deficits from across the United States controlled a PR2 in Atlanta, GA to perform a modified Action Research Arm Test (ARAT) and a simulated self-care task. Participants achieved clinically meaningful improvements on the ARAT and 12 of 15 participants (80%) successfully completed the simulated self-care task. Participants agreed that the robotic system was easy to use, was useful, and would provide a meaningful improvement in their lives. In the second study, one expert user with profound motor deficits had free use of a PR2 in his home for seven days. He performed a variety of self-care and household tasks, and also used the robot in novel ways. Taking both studies together, our results suggest that people with profound motor deficits can improve their quality of life using robotic body surrogates, and that they can gain benefit with only low-level robot autonomy and without invasive interfaces. However, methods to reduce the rate of errors and increase operational speed merit further investigation.Comment: 43 Pages, 13 Figure

Editorial: Relevance Theory and Intercultural Communication Problems

This editorial to the special issue of RiL dedicated to relevance theory and problems of intercultural communication addresses the general requirements that a theory of communication must meet to be applicable to the analysis of intercultural communication. Then it discusses criticism levelled against Grice’s theory of conversational implicature and Brown and Levinson’s theory of politeness on the grounds that these theories were not universal enough to be applied to all data. Finally, it offers some remarks on the applicability of relevance theory to intercultural pragmatics