Science and Industry

THE smallest containers in the world are a twenty-five-thousandth of an inch in diameter, the size of one of the smaller bacteria. Called micro-capsules, they enclose the contents — which can he a liquid, a solid, or possibly even a gas under pressure — in a plastic film. Encapsulated in this way, soluble materials become nonsoluble, liquids turn into solids, harmful materials can be handled without danger, two substances that would normally react on each other can be mixed and the reaction postponed to some future time.

The National Cash Register Company originally developed the microcapsules for use in a special paper that makes copies without carbons. Tiny particles of a colorless dye are encapsulated and coated on the back of the paper; typing or writing on the sheet breaks the capsules, releasing the dye, which reacts with a chemical on the paper to form colored ink, which makes the copy on the next sheet.

NCR plans to license its patents on a broad basis, and Stanford Research Institute is studying possible applications in other fields. In farming, microcapsules might enclose fertilizers or pesticides in water-soluble containers that would release the active ingredient slowly, so that it would act over a period of time. A similar application is possible in medicine: encapsulated drugs could be injected into the patient, to be carried deep into the body before the capsule released its cargo. In packaged food mixes, volatile substances that give flavor and aroma could be encapsulated to preserve their contents until released by the cooking. The microcapsules could even be used in rocket fuels to keep mutually reactive agents separate until the container walls were broken down by the heat of firing.

Electronic medicine

Electronics has added a new weapon to the armory with which the physician fights pain. In pioneering operations at the Medical School of the University of Mississippi, two patients have been kept completely unconscious by electrical currents pulsing through their bodies. Although the procedure has been developed experimentally with animals, it is thought to be the first planned and controlled use of electricity as an anesthetic for human patients.

The Mississippi researchers, who have studied the problem for four years under a grant from the U.S. Army, have developed a simple device that costs only $150. Consisting only of an oscillator and an amplifier, it produces a 700-cycle current of 30 volts and 50 milliamps, which is transmitted through the patient’s body by electrodes on either side of his forehead. The patient becomes unconscious in less than a minute, and wakes up in about the same time after the current is turned off. No undesirable side effects have been observed.

The American Medical Association notes at least eighteen engineering developments that became available for medical use in 1960. Among them:

A simple stapler that enables the surgeon to reconnect severed blood vessels with stainless steel;

An X-ray fluoroscope that uses a television image tube to magnify the brightness of the image a thousandfold, drastically reducing the time that the patient is exposed to radiation and enabling consulting physicians to view the X-ray images in a normally lighted room;

A Japanese camera, the size of a finger tip, that photographs the inside of the human stomach;

A digital computer that enables the doctor to fit together great quantities of clinical data about his patient, which he would otherwise never have time to correlate;

A monitoring device, reporting simultaneously on changes in blood chemistry, fluid balances, blood pressure, and other sudden chemical and physiological events, that helps doctors keep close watch on a patient during the crisis of an illness;

A fluorescent microscope for office use that is expected to provide quick diagnosis of several communicable diseases, including rabies, syphilis, and streptococci infections, through study of smears.

Despite these successes, James Hillier, vice president of RCA Laboratories, believes that the application of new technology to medical science and public health is lagging. An example, Mr. Hillier declares, is the microanalyzer that uses X rays to determine the distribution of chemical elements within the structure of a cell: although several have been built and proved valuable, none has been standardized lor commercial production.

The problem, as Mr. Hillier sees it, is basically economic. For every dollar spent in exploratory work on a new device, ten dollars must be spent for advanced development and engineering, and about a hundred dollars more for product design, tooling up, and market development. Since the maximum potential sales for laboratory and hospital devices range from a few hundred to a few thousand, prospective sales will not cover the investment in engineering and production. The electron telescope, Mr. Hillier points out, has been on the market commercially for twenty years and still has not returned the manufacturer enough profit to cover his development costs.

One solution proposed is the establishment of engineering centers for development of new devices into practicable forms, to be supported by government subsidies, pools of private companies, or foundation grants.

Mr. Hillier offers no solution of his own, but he provides an impressive glimpse of what technology might do for medicine if given the opportunity. In the future hospital, he suggests, routine measurement could be done by automatic devices reporting by radio. “Each patient would be equipped with such measurement units, consisting of sensors and extremely small radio transmitters built into bracelets, pendants, or other unobtrusive forms for wearing without inconvenience or discomfort. Through these devices information on the patient’s temperature, pulse, heart action, and other key functions would be transmitted to a bedside or built-in receiver and transmitter for relay to a display board located centrally on each floor within view of the head nurse and her staff. With such an arrangement, the skilled nursing help in the hospital would be free to provide the more specialized care requiring their individual attention that frequently cannot be given today because of heavy demand upon a small staff.

Mr. Hillier adds: “I am not painting a science-fiction picture of the future. Everything in the system described here is entirely feasible today, in the technical sense. What is needed, however - as in so many other aspects of medical electronics - is the economic justification for proceeding to develop the system into a form for general application.”

Preserving books

Today books use only about 2 per cent of the output of the American paper industry; most of the rest goes into things that are thrown away. As a result, say experts, long-range durability doesn’t get much attention from manufacturers. Yet, for the preservation of Western culture that 2 per cent may be more important than all the rest put together, and for books, durability is very important indeed.

A study made at the Virginia State Library has come up with the shocking report that 90 per cent of the books printed in the twentieth century are not going to be usable fifty years after publication. W. J. Barrow, document restorer at the library, has tested a random selection of books with ingenious machines that tirelessly and exactly measured how many times paper can be folded before breaking and what force is needed to tear a page. He has found that only one per cent of the books printed since 1900 can be considered in first-class condition. The older ones are already getting weak and brittle, and are crumbling in their bindings.

In contrast, the paper in some books printed five hundred years ago is still white, strong, and flexible. Tests show that the culprit is acidity. Most modern book paper is gravely weakened by the use of acid sizing.

Working with papermakers, Barrow has developed a long-lived paper made of chemical wood pulp that does not cost any more than ordinary types. A nonacid sizing called Aquapel-Kymene, made by the Hercules Powder Company, keeps the paper alkaline, while calcium carbide is added to serve as a buffer during storage. This paper stood up under forty-eight days of 100° C. heat, the equivalent of four hundred years of aging. Now the problem is to get the commercial manufacturers into the act.

For librarians who arc worried about their present books, Barrow has developed a simple preservative treatment: the books are removed from their bindings and soaked overnight in a solution of calcium and magnesium bicarbonates, which destroys acidity. Trustees may shudder at rebinding costs, but it is better to pay them now than to wake up someday to find most of the books on the shelves crumbling into dust.

A new conveyer belt

A new type of belt-conveyer system, devised by a Cleveland engineer, has sharply cut the time required to handle garments in a huge distribution center. In the conveyer, a V-belt, made by Goodyear, rides in a flat channel in the top of a special welded-steel tube developed by Republic Steel. At the end of each section, the belt delivers its load of garments to the next section, runs over a pulley, and returns through its tube to its starting point. Moving quietly at faster than a hundred feet a minute, the conveyer requires no lubrication. Thus it remains clean, and maintenance costs are thereby cut.

In the distribution center of Bobbie Brooks, Inc., a Cleveland clothing manufacturer, the belt system is teamed with automatic rack releases to provide a completely mechanized system of filling orders. Garments are stored on tilted racks with gates that open by remote control, permitting the units to slide down onto the conveyer belt. Pressing coded buttons at a central panel, an operator can release the exact quantity of each style, size, and color needed, and the conveyer carries the garments automatically to an assembly point. Orders that formerly took three to six hours to fill can now be completed in less than thirty minutes.

Homes for growing oysters

An oyster may look well armored in his craggy shell. As oystermen know to their sorrow, however, their charges are easy prey to a host of enemies, particularly before the oysters are fully grown. Interior Department scientists, worried about declining U.S. oyster production, are trying a variety of approaches to the problem. At the Milford, Connecticut, biological laboratories of the Bureau of Commercial Fisheries, oyster experts are developing chemical barriers to protect the oysters as they lie on the ocean bottom.

The scientists surround shellfish beds with belts of sand impregnated with chemicals, mainly heavy chlorinated oils, known to be toxic to drills, starfish, and crabs. The effects of the chemicals are drastic: the drills swell greatly, become paralyzed, and die. The starfish rays first curl at the tips, then disintegrate on the underside, and finally are cast off. The crabs lose their equilibrium and have convulsions.

In one experiment an eight-inch belt of sand mixed with orthodichlorobenzene was maintained for fourteen months, during which time a fresh supply of oyster drills was placed in the experiment trough every two weeks. Not one drill crossed the barrier. In other experiments, the scientists scatter the chemically treated sand over oyster beds to kill drills, starfish, and other pests in the beds themselves.

The scientists hope that by varying the chemicals and the method of application they will rout a wide variety of the enemies of shellfish, including mud shrimps, snails, flatworms, and even fungus diseases. One important question remains to be settled: the scientists must make sure that the chemicals do not affect the oysters and clams in such a way as to make them unfit to eat. They believe the chemicals, being insoluble or only slightly water soluble, probably would not pollute the water or injure sea animals or plants that do not come in contact with the treated sand.

At another Commercial Fisheries Bureau laboratory, at Woods Hole, Massachusetts, a group of biologists are trying a different solution: moving the young oysters out of the path of attackers that is, off the bottom — at the stage when they are most susceptible to attack. Borrowing a technique from the Japanese, the Woods Hole biologists built a cedarlog raft from which they hung wired Strips of empty shells to which young oysters had fastened themselves.

They found that the raft oysters had a far higher survival rate than a similar group of oysters planted on the bottom. Of the oysters that spent a year on the raft plus a year on the bottom, about 60 per cent survived. The seed oysters that had been planted on the bottom in the same area — with no attempt made to control predators - were 90 per cent lost over roughly the same period. At the same time, the raft oysters grew far faster, although they had thinner shells, than a control group on the bottom, reaching market size in two years instead of the usual four or five.

Now the Massachusetts Department of Marine Fisheries is testing a raft in which ninety-six bushels of oysters live in ninety-six wire trays, designed to save commercial oystermen the labor of hanging the oysters out on a line. The fisheries people are also using the raft to check the different growth rates of different oyster strains in the hope of developing breeds that will fatten quickly to an edible size. Elsewhere, other types of homes for growing oysters are being tried out. Chesapeake Bay oystermen have found that the oysters will happily make their homes on slag from a steel mill. In France, an inventor has developed a pyramidal wooden frame wound with string on which the larvae settle.

The Woods Hole researchers hope that there will be plenty of experimentation. For, they grimly warn, “unless drastic changes take place in the methods of oyster culture now practiced in Massachusetts, the oyster industry of this state is doomed.”