The International Atomic Energy Agency (IAEA) organized a scientific visit to IAEA headquarter in Vienna, Austria from March 8-12,1999. The objective of the visit was to

strengthen the project design, management & evaluation capacity of IAEA technical co-operation projects in Ethiopia. Also, through this visit experience was shared on new approaches of the Agency’s information management, design, programming, appraisal & evaluation mechanisms of technical projects.

In general, this scientific visit shows or highlights the increasing scope of the technical co-operation program of Ethiopia with the Agency. Ato Fanta Demissie from the Mine, Water & Energy department participated in the visit representing the Ethiopian Science & Technology Commission (ESTC).

The AFRA-FMC held a meeting in Austria Vienna from 8-12 March 1999. On behalf of Ethiopian Science and Technology Commissioner, Head, MWED, Ato Mulugeta Amaha attended the meeting. The AFRA-FMC is a committee composed of five representatives from AFRA member states and the AFRA coordinator at the IAEA that is responsible for the implementation of AFRA projects. Currently AFRA has fourteen operational projects in various areas of application of nuclear science and technology including agriculture, human health, radiation protection, water resources, energy and industrial applications. Ethiopia is elected as chair of AFRA and also member of its field management committee for a term of one year, beginning Sept. 1998.

A-three day workshop on the establishment of ERHR strategy for Amhara (Jan. 21-23) and Southern Peoples Regional States (March 18-20) was held in Bahir-Dar and Awassa respectively. The workshop was organized by the Health Department of the ESTC in collaboration with Regional Health Bureaus. The objective of the workshop was to implement the National Health Science and Technology Policy using Essential Regional Health Research strategy, taking in to consideration Region specific health problems. Six scientific papers (3 from the Health Department of the ESTC and the remaining 3 from the Regional Health Bureaus) were presented in the workshop. Workshop participants (35 in Amhara and 45 in SNNPRS) were drawn from all relevant Regional institutes, NGOs, religious organizations, Communities and the ESTC. Following the workshop, Essential Amhara Region Health Research Council, composed of 23 members, and Essential Southern Region Health Research Council, having 25 members have been established. These councils are all-inclusive being headed by social sector head of the Regional Governments. The councils are expected to play an active role in, among others, advising their Regional Governments about ERHR.

Extracts From Other Sources

Could algal colonies be the answer to global warming?

Great balls of concrete could take some of the heat out of global warming, claim chemical engineers from Lousiana State University. They say the balls will be colonised by algae which "fix" carbon from the atmosphere and trap it in sediment.

Their plan is to dump concrete hemispheres dubbed "reef balls" into estuaries and coastal waters, providing large surface areas for marine algae to colonise. The researchers believe that each hemisphere could remove hundreds of kilograms of carbon from the atmosphere every year.

The Louisiana team aims to attract algae that grow 20 times faster than free-floating forms. As they grow and photosynthesis they extract carbon dioxide from the surrounding waters, which is replenished by co2 from the atmosphere. When the algae die, they fall to the seabed and become part of the sediment. The net result is the removal of CO₂ from the atmosphere.

Carl Knof, chair of chemical engineering at the university, said: "We are trying the idea out in the lab now using balls 15 centimeters across. But in the next stage, in the ocean we will be sinking balls three meters across or more."

One challenge has been to make the concrete chemically neutral. Normal concrete is too alkaline for microalgae to colonies. Sea water will eventually neutralize it, but not before organisms with less power to "fix" CO₂ have invaded the concrete surface.

Ironically, neutralizing the concrete means applying CO₂ to it under high pressure, while the concrete is still wet. Treating the concrete with a foaming agent creates a sponge-like surface which has a bigger surface area for the algae to grow on. "A hollow hemisphere or reef ball about 100 square metres of active surface area for microalgae growth. Each reef hemisphere could remove 200 kilograms of carbon from the atmosphere each year, and this process would continue indefinitely," says Knopf. The team has calculated that to soak up all the CO₂ the US produces in a year would require almost a billion-and-a-half balls. Still, the team reckons, it’s a start. The balls could eventually be used to dispose of carbon dioxide from fossil-fuel power plants. Emissions could be pumped into the ocean close to a concrete reef system, say the researchers.

The first test balls could be lowered into the ocean as early as next year. Knopf plans to make the hollow balls buoyant enough to float into place by putting an inflated rubber ball inside them, and to sink them by gradually deflating the ball. Once in place, says the team’s marine biologist Bob Gambella, the balls will both consume carbon dioxide from the ocean and provide conditions on the sea bed similar to those of a natural reef.

New scientist, June 1998

A team of international scientist have announced they have traced the origin of the AIDS virus to a closely related virus in subspecies of chimpanzee in Africa.

The scientists, who reported their findings on January 31 at the Conference on Retroviruses and Opportunistic Infections, being held in Chicago, said that research will now focus on why the human immunodeficency virus (HIV) that causes AIDS is lethal for humans while the related virus causes apparently no illness in the chimpanzees, even though humans and chimpanzees are 98 percent genetically similar.

Although Scientific researchers have long suspected that HIV-1, the type of AIDS virus that has caused the overwhelming majority of cases in the world, came from chimpanzees, scientists have not been able to identify the precise subspecies until now. The chimpanzee virus is known as SIVcpz, or "simian immunodeficency virus chimpanzee."

"The chimpanzee, which has served as the source of HIV-1 also quite possibly holds the clues to its successful control," the head of the research team, Dr. Beatrice Hahn of the University of Alabama at Birming-ham, said in an interview.

Hahn, whose paper will be published in this week’s issue of the journal Nature, said despite the enthusiasm with the discovery, her team is worried about the fact that the subspecies in which SIVcpz was found is at "the brink of extinction" in its natural habitat in West and Central Africa. Hahn believes the chimpanzee’s extinction represents a danger to science because much more needs to be learned about the infection in chimpanzees in the wild.

Hahn’s team has confirmed the origin of the AIDS virus by analyzing frozen tissue from Marilyn, a chimpanzee who died in 1984 at the age of 26. The researchers have been able to perform various kinds of genetic analysis that were unavailable at the time Marilyn died. The chimpanzee subspecies lives in the African region where AIDS is thought to have started.

HIV presently infects about 35 million people worldwide, with the first infection probably having occurred 50 years ago, scientists have reported. Hahn and her colleagues said that they have conclusive evidence that the HIV virus has spread on at least three distinct occasions. Hahn believes in the theory that humans have been infected from chimpanzees in Africa through exposure to their blood in hunting and when dressing meat. However, why the epidemic came when it did is not known precisely.

Dr. Anthony Fauci head of the National Institute of Allergy and Infectious Diseases, said in an interview that his federal institute would finance substantial research on the simian virus, He said one focus of the research will be on whether the different outcomes of infection in humans and chimpanzees result from small changes in the genetic makeup of the virus or the host. The latest findings might lead to new tests to discover viruses in nature that could cause human disease. "No one wants to miss detecting the next HIV epidemic," said R. Harold Jaffe, a leading AIDS researcher at the Center for Disease Control and Prevention in Atlanta, Georgia.

Because the chimpanzees are able to live with HIV without developing the illness, scientists hope their discovery will be helpful in improving therapies and eventually developing a vaccine against the AIDS virus.

Addis Tribune, February 1999.

The world may have a brand-new element, created by a team of chemists from Russia and the US. It has 114 protons-a "magic" size that theoreticians predict should be much more stable than other super-heavy atoms. The chemists bombarded a neutron-enriched isotope of plutonium, which has 94 protons, with an isotope of calcium.

"We saw an atom flying and then thirty seconds later, we saw an alpha decay," says Ken Moody a team member based at Lawrence Livermore National Laboratory in California. "It could be the decay of element 114." The Russian scientists on the tea came from the Join Institute for Nuclear Research in Dubna near Moscow.

"It looks pretty good, they’re not going off half-cocked" says Albert Ghiorso, a physicist at Laswrence Berkeley National Laboratory in California. "This is the experiment I’ve been trying to do for the past 25 years."

If their findings are confirmed, the long-sought element could validate the theories about the factors governing the stability of very heavy atoms.

New Scientist, January 1999.

Rotten Eggs

The risk of food poisoning is increased by the coon practice of starving chickens for up to two weeks to boost egg yield, say scientists and animal rights campaigners.

In a process called "forced molting", food is withheld from laying hens nearing the end of their productivity. This forces them to moult and also stops the laying eggs.

When feeding is resumed, they start laying again and continue for several months longer than they would have otherwise. But at last week’s international Poultry Exposition in Atlanta, Georgia, Karen Davis of the Virginia based animal welfare group United Poultry Concerns said the practice makes chickens and their eggs ore prone to Salmonella infection. Forced moulting is banned in Britain though still widespread in the US.

Her claims are backed by Peter Holt from the US Department of Agriculture in Athens, Georgia. The Food and Drug Administration says it is considering the group’s call for a ban.

The host feels nothing because the protein also mops up histamine, which normally triggers irritation and an immune reaction. "It stops the victim feeling any distress, so the insect gets more time to feed," says Ann Walker, joint leader of the tea at the University of Arizona in Tucson, which reports the protein’s structure in the Journal of the American Chemical Society (vol. 121, p 128).

New Scientist, January 1999

FEATURES

Y2K And Its Implications*

by Y2K Readiness Project Office, http://www.telecom.net.et/y2k

At midnight, December 31, 1999 most computers will change their dates to the year 2000. Some, however, might ‘think’ that the year has become 1900, and cease to function properly. This is also the case with machines, such as video recorders or modern vehicles, with a ‘chip’ in. The problem arises because the systems count dates in two digits, and the year 1999 is ‘99’ and the year 2000 (and 1900) is ‘00’.

The year 2000 problem is caused by a short cut used in many computers and microchips. The root of the problem lies in the common usage of only two digits to the year portion of a date, e.g. 21/10/94, instead of 21/10/1994. This is a widespread style, and has been used for many years by manufacturers, programmers and users of computer systems. As a result, many operating systems, packages and applications now use two-digit-year formats to determine date and to perform date-based calculations, sorting, etc. For example, in the two-digit year format 1991 is written as 91, 1900 as 00, and 2000 as 00. Such kind of a problem can create either erroneous result or shut down a system. The errors can occur in calculations, date stamping, ordering and indexing.

The Y2k problem is associated with a leap year as well. This can complicate the problem. In order to understand the problem, it is better to put important parameters in leap year calculations. There are three rules by which the Gregorian calendar uses to determine leap year.

1. Years divisible by four are leap year unless…
2. Years also divisible by 100 are not leap year, except…
3. Years divisible by 400 are leap years.

Therefore, the year 2000 is a leap year according to rule number three. But, most of the manufacturers & programmers were not aware of rule number 3. It was assumed to be not a leap year.

Generally the problem occurred for the following reasons:

Cost of memory was too high
Computers were slow
Extension of useful life of the computing systems
Human habit

Wrong formula of leap year calculation.

The Y2K problem is very widespread. It affects hardware (BIOS, read-time clocks), embodied systems, languages and compilers, operating systems, random number generators, security services, database management system, transactions, processing systems, banking systems, spreadsheets, PBXs, phone systems, and more. Generally, all electronic systems which are using dates may be threatened. Communications systems, aircraft systems, manufacturing etc. could be affected by the problem (i.e. they may not function at all or they may do wrong things which they are not expected to do).

How Big Is The Problem?

The problem is affecting the whole world. There is no country which is immune to the problem. The Gartner Group leading experts in this area, expect costs associated with the problem to total USD $300-600 billion by end of 1999.

What Is The Solution?

The solution of the problem is to identify priorities, own an action plan, control and monitor the project of Y2K, avoid the deadline (Jan 1, 2000) and focus on contingency plan. In addition one should not assume that all new applications and systems are immune to Y2K. Thus, it is advisable to incorporate all damages caused by Y2K in warranty or in an agreement.

Implications To Ethiopia

Y2K national readiness project has been initiated by the ESTC and endorsed by the PM’s office in July 1998. The management and operation of the project has been approached by first establishing a Y2K National Technical Committee. The Committee’s performance is guided by the terms of reference and action plan it has developed and approved by the ESTC and the PM’s office. The world bank has finally assisting its activities.

Sectors and institutions have been labeled as priority if they fall under the following three major Y2K risk factors:

1. Survival risk (water supply, power generation, health(hospital, lab. etc)
2. Economic risk (banking & insurance, communication, transpiration etc)
3. National security risk (defense, national security services, police etc)

The committee has given serious attention not only to the existing risk assessment and remedy but also to the preventive mechanism so as not to acquire non-compliant system.

Organizing and conducting of training and awareness programs targeted to different categories of the society and government structure is a vital component of the action plan. The committee has completed training and publicity programme through media such as the national TV/radio, and different government and private newspapers. In order to achieve at the intended goal with regard to the level of awareness and technical capability, the committee has organized and conducted a series of programs both at federal and regional levels. In order to facilitate the follow up of the status of national year 2000 readiness program, the committee has developed a web page posted on the Ethiopian Telecommunication web site: http://www.telecom.net.et/y2k an announcement will be made to the attentions of the concerned groups for visit.

It has also become a day to day activity of the ESTC and that of the Committee members to give advisory service to various government, NGO’s and private companies on the issue of Y2K, particularly on the concept and nature of the problem, testing procedures, remedial options, and preventive measures, etc.

Re-Using Rubber

(by Abebaw Kassahun)*

Rubber is produced from either natural or synthetic sources. Natural rubber is made from a milky white fluid called latex that is found in many plants; synthetic rubber are produced from unsaturated hydrocarbons. In practice, the main source of rubber in the South is scrap tyres and inner tubes, which are made from synthetic rubber. This article will look at the small-scale reclamation and re-use of rubber tyres and tubes.

The different types of synthetic rubber include neoprene, buna rubber and butyl rubbers, and they are usually developed with specific properties for special applications. Styrene-butadiene rubber and butadiene rubber (both buna rubbers) are commonly used for tyre manufacturing. Butyl rubber, since it is gas-permeable, is usually used for inner tubes. Tyres are made up of both

natural and synthetic rubber, together with carbon, nylon or polyester cord, sulfur, resins and oil. During the tyre-making process, these are vulcanized into one compound product that is not easily broken down.

Modern rubber manufacture involves a sophisticated series of processes such as

mastication, mixing, shaping, molding and vulcanization. Various additives are included during the mixing process to give desired characteristics to the finished ESTC. product. They include:

Fillers are used to stiffen or strengthen the rubber. Carbon black is a commonly used anti-abrasive. Pigments include zinc oxide, lithophone, and a number of organic dyes. Softeners, which are necessary when the mix is too stiff for proper incorporation of the various ingredients, usually consist of petroleum products, such as oils or waxes, pine tar or fatty acids.

The molding of the compound is carried out once the desired mix has been achieved and vulcanization is often carried out on the molded product.

Vulcanization

Vulcanization gives rubber its characteristic elastic quality. This process is carried out by mixing the latex with sulfur. The addition of sulfur to rubber & heating the mixture greatly enhances the physical properties of rubber. The materials no longer becomes tacky in warm weather & in cold weather it does not become brittle. The material is much tougher & the quality of product made this way results in service for much longer period of time.

Why reclaim or recycle tyre?

Rubber recovery can be a difficult process. There are many reasons, however, why rubber should be reclaimed or recovered.

 Tyre re-use and recovery

There is enormous potential for reclamation and re-use of rubber throughout the world. In the USA less than 7 percent of the 242 million tyres produced annually are recycled. An additional 11 percent are incinerated, but the vast majority is landfilled, an extremely bad practice. It takes over 100 years for a tyre to disintegrate at ambient temperatures and if landfill they trap air, making the fill unstable; they trap water, providing a breeding ground for insects; and in the end they rise to the top of the fill.

Recovery alternatives

There are many ways in which tyres and inner tubes can be re-used or reclaimed. The waste management hierarchy dictates that re-use, recycling, and energy recovery, in that order, are superior to disposal and waste management options.

Product repair

Re-use results in the greatest saving of energy and resources, so damaged or worn tyres are, whenever possible, repaired. Tubes can be patched and tyres can be repaired by one of a number of methods. Regrooving is a practice carried out in many developing countries where regulations are less stringent and standards (and speeds) lower than in the west. It is often carried out by hand and is labour intensive. Regrooving is difficult to do safely on automobile tyres, but lorry tyres are often made with some regrooving in mind.

Secondary re-use

The secondary re-use of whole tyres is the next step in the waste management hierarchy. Tyres are often used for their shape, weight, form or volume. Whole tyres are often used for erosion control, tree guards, artificial crash barriers, docking fender, fences, or as planters. They can also be used to hold a large or heavy item in place, such as tarpaulin covering or corrugated iron sheeting. In the South there are additional uses, such as lining wells.

Physical recovery

The next step in the hierarchy involves break down and re-use. The rubber used in tyres in relatively easy to reform by hand. It behaves in a similar manner to leather, and has in fact replaced leather for a number of applications. The tools required for making products directly from tyre rubber are not expensive and are few in number. Shears, knives, tongs, hammers etc., are all common tools found in the recycles workshop, along with a wide range of improvised tools for specialized applications or more sophisticated tyres. The materials are recovered mechanically and it is very labour intensive, particularly as tyres become more sophisticated & new materials are used for strengthening and reinforcement. Shoes, sandals, buckets, motor vehicle parts, bushes, doormats, harnesses, hinges, water containers, pots, plant pots, dustbins, and bicycle pedals are among the many products manufactured, in addition to the production of other tyres, such as for carts or wheelbarrows. Old inner tubes also have many uses; swimming aids and water containers are two simple examples.

Chemical and thermal recovery

These types of recovery are not only lower in the waste management hierarchy, but are also higher technologies requiring sophisticated equipment. The applicability of such technologies for small scale applications in developing countries is very limited at the moment, as it requires a large capital investment, and a guaranteed supply of tyres. The money may be found but most of the tyres are already being recycled. Recovering the rubber in this way could potentially enable southern countries to produce more sophisticated and high-value products, however, including new tyres.

Energy Recovery

Tyres consist of around 60 percent hydrocarbon, which is energy that can be used directly in processes such as cement making or to raise steam for a variety of uses, including electricity generation. Again, this technology requires sophisticated plant and its application is limited when looking at small-scale enterprise. Tyres are not as efficient a fuel as coal but are usually better than gas oil.

Landfill

Landfill is the final step in the waste management hierarchy although it is rarely needed in the South. The landfill disposal of tyres, if properly managed, does not constitute and environmental problem, however, concerns about conserving resources and energy have increased apposition to landfilling.

References

1. Appropriate Technology, Vol. 25 No. 2, Sep. 1998 

2. Scientific Encyclopedia 1983, 6^th edition New York, USA.

 Note to readers