Notes from the Lab


STRAW-BASED INSULATION FOR PAKISTAN

In northern Pakistan, buildings are typically made of uninsulated stone or cement block -- materials that provide little protection against the cold temperatures of winter. Wood and other fuels are scarce, and indoor temperatures in winter are frequently only a few degrees above those outdoors. A straw-based insulation developed by Energy Laboratory researchers in MIT's Building Technology Program could help boost those temperatures while saving fuel.

Drawing on a technique developed by ICI Polyurethanes, the researchers place milled straw inside a tumbler and spray it with droplets of an adhesive. The straw is removed, placed in a frame, pressed and heated. Half the cost of polystyrene (the only other rigid insulation available in Pakistan), the straw insulation could be made in local factories using local materials, simple machinery, and little energy. Only small amounts of adhesive would have to be imported.

Case studies at four Pakistani schools show that installing straw insulation could cut energy requirements by half or more. The methods could be applied in many developing areas using straw or other available waste materials.

The team was led by Professor Leon Glicksman and Associate Professor Leslie Norford of the Department of Architecture (Dr. Glicksman also holds an appointment in mechanical engineering). The work was supported by ICI Polyurethanes; the American Society of Heating, Refrigerating, and Air-Conditioning Engineers; and the Aga Khan Housing Board for Pakistan.

-Nancy Stauffer, Energy Lab

DREAMING AND LONG-TERM MEMORY

Matthew Wilson has worked hard to puzzle out how the hippocampus -- a small but critical paired structure buried deep in the brain -- works as a catalyst for memory formation. Now the assistant professor of brain and cognitive sciences is exploring whether the hippocampus, in concert with memory machinery elsewhere in the brain, helps ensure that particular memories will become enduring ones as we sleep.

"The idea," he said, "is that we often dream about things that are significant for us, and that this can lead to the formation of long-term memories." That doesn't mean a bone-chilling nightmare is an example of memory consolidation at work. In fact, he said, the dreams involved in consolidating memories are unlikely to be the kind that wake us up, or even enter our conscious thoughts.

Professor Wilson noted, though, that the hippocampus actively communicates during dreams with parts of the brain where long-term memories are lodged. There are signs, he added, that at least some of this back-and-forth represents a sorting process that leads us to retain some memories while letting others slip away. The work is funded by The Merck Foundation and the RIKEN-MIT Research Center.

-Richard Anthony, Spectrum

This column features summaries of MIT research drawn from several sources. If you have an item to suggest, send it to Elizabeth Thomson, News Office assistant director for science and engineering news, Rm 5-111, or thomson@mit.edu.

A version of this
article appeared in the
March 3, 1999

issue of MIT Tech Talk (Volume
43, Number
21).


Topics: Education, teaching, academics

Back to the top