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Homes to plug into the Internet

Home computers could soon connect to the Internet through electrical power lines that would supply data faster than a phone line. Northern Telecom of Canada and Norweb Communications in the UK say that they have transmitted data at speeds of up to one megabit per second – the same speed as an office computer network – using electrical power lines. The systems relies on a protocol that can suppress noise in electrical cables.

Providing cheap high-speed telecommunications access to the home has been the goal of many companies over the past few years. The high cost of installing new phone lines such as ISDN has limited the expansion, as have the low availability of cable modems. This makes transmitting data over electricity lines very attractive.

The new system does have a significant limitation – the transmission protocol cannot cope with the voltage step-down at a substation. High-speed fibre-optic lines must therefore be provided to the substation. Another problem is that as the number of users increases, the speed of the network drops to about 500 kilobits per second.

New sites for Oxford Instruments

Oxford Instruments, one of the UK’s leading physics-based companies, demonstrated its economic confidence by opening two new buildings last month. It unveiled an £8 m factory at Tubney Woods in Oxfordshire to meet the expansion needs of its research instruments division, while the microanalysis group opened a new £6 m building in High Wycombe to meet an expected rise in demand for its X-ray and electron-beam analysis equipment.

The Tubney Woods factory is the latest in a long line of triumphs for Oxford Instruments. Founded in 1959, the company has in many ways become the archetypal high-tech success story. A specialist in superconducting magnets and advanced instrumentation, it now employs about 1400 staff worldwide and exports 85% of its output. Turnover in the 12 months to the end of March rose slightly to £147.1 m, and the firm made pre-tax profits of £23 m over the same period, a rise of 7%.

EC advisory body slims down

The organization that gives scientific advice to the European Commission has been slimmed down and steered towards social science. Membership of the European Science and Technology Assembly (ESTA) has been cut from 100 to 61, with 11 members sitting on the bureau that conducts most of the business. The assembly meets this month to elect a chairman and agree its work plan.

Science gets a higher profile in Ireland

Treacy has previously held posts in the departments of enterprise, energy and the environment. Following a reorganization, Treacy’s ministry will bridge the newly formed Department for Education and Science and the Department for Enterprise, Trade and Employment. As a junior minister, he will report to Mary Harney, minister for enterprise, trade and employment, and Micheál Martin, minister for education and science, both of whom represent science at Cabinet.

“This reorganization is a very positive development, ” says Vincent McBrierty, a polymer physicist at Trinity College Dublin. ” I am also very pleased that the minister is at the interface between education, science and the commercial world. Treacy does not have a technical background but he is worthy and capable and goes to great pains to inform himself, ” he says.

US science budget rises

The National Science Foundation, NASA and civilian science at the Department of Energy will all get more money in this financial year, which started on 1 October. The funding increases are greater than the Clinton Administration’s requested (Physics World March p5). On the negative side, the high flux beam reactor at the Brookhaven National Laboratory will remain closed for at least a year, and funds for the large hadron collider at CERN, the European particle physics lab, have yet to be cleared. Basic research at the Department of Defense will also be funded at no more than last year’s levels.

Flatter TV displays

Though Active Matrix displays used on portable computers produce high quality flat displays, the yield from the manufacturing process is low, and the cost of manufacture significantly higher that the cathode-ray tube. The largest active matrix display in commerical production is only 15 inches, compared to 45 inches for the humble cathode ray.

Now Nalin Kumar and Chenggang Xie in Texas have developed a new method of making a flatter cathode tube display in Patent 5675216.

Their display consists of a layer of conductive material and a layer of amorphic diamond film. The latter functions as a low effective work-function material, deposited over the conductive material to form emission sites. The emission sites each contain at least two sub-regions having differing electron affinities. This is the first patent awarded that uses a amorphic diamond film in a cathode.

Light up your heart

Pacemakers work by sending a electrical pulse from a pacemaker through a lead to endocardial tissue, a layer of tissue which is then simulated inside the heart. The lead passes into the heart through a vein.

One of the difficulties with installing pacemakers, is deciding which vein to use, and how to cope with the bodies reaction to it. Shortly after placement, blood clots form near the lead caused by the irritation of the endocardial tissue by the leads electrode tip. This keeps the cable in place inside the heart.

Although pacemakers have improved tremendously, sometimes the leads fail, or the tip has to be moved to simulate a different section of the heart, resulting in additional operations to the patient. Because of this some patients may come to have as many as four or five unused leads in their heart.

Some of the methods to remove the lead are quite dangerous. Patent 5674217 uses a new solution involving a laser.

A lead extraction device containing a catheter to overlap the damaged lead is inserted into the beating heart with its movements synchronized to the cardiac cycle. The catheter is thereby guided by the lead. The catheter has at least one optical fiber to emit laser light from the distal end and thereby separate the lead from fibrous scar tissue. Laser light is then used to separate the pacemaker lead, from fibrous scar tissue and thereby permit the implanted object to be extracted from a body.

The extraction device features a catheter having a central lumen dimensioned so a pacemaker lead will fit within. A means for generating a control pulse in response to a sensed ECG signal permits the catheter to by synchronized to the cardiac cycle. In such a manner laser light may be controlled so as to avoid striking the heart at a vulnerable period in the cardiac cycle.

CERN hustings

The candidates are: Robert Aymar, director general of the ITER fusion project; Walter Hoogland of NIKHEF in Amsterdam, a former director of research at CERN; Luciano Maiani of the University of Rome, president of the CERN council; and Albert Wagner, director of research at the DESY lab near Hamburg. It is also possible that the current director general, Chris Llewellyn Smith, will remain for a further five years, handing over when the large hadron collider is almost finished in 2004. A decision is due to be made later this month.

Japan thinks big on synchrotrons

Japan’s 8 GeV Super Photon Ring – the Y110 bn (about £560 m) third-generation synchrotron radiation source better known as SPring-8 – was officially opened at the Harima Science Garden City last month. SPring-8 is the highest energy synchrotron radiation source in the world – the European Synchrotron Radiation Facility and the US’s Advanced Photon Source operate at 6 GeV and 7 GeV, respectively.

The facility comprises three accelerators: a 1 GeV linear accelerator, an 8 GeV booster cyclotron and an 8 GeV storage ring with a circumference of 1436 m. So far 18 beamlines are operational, including 10 public beamlines. SPring-8 was funded by the Science and Technology Agency, which will pay the annual running costs of Y10 bn, and will be managed by the Japan Synchrotron Radiation Research Institute, which will be responsible for all future upgrades and new beamlines.

The SPring-8 management expect about 2000 users per year, including many from abroad. The machine’s location should help – the tree-studded rolling hills around Harima are only 60 minutes from the new Kansai International Airport, which serves Osaka, Kyoto and Nara and their considerable scientific communities.

JET sets fusion record

Fusion experiments at the Joint European Torus (JET) fusion project in Oxfordshire, UK, are more than halfway to breakeven – the point where the power produced by the reactor equals that supplied to it. But a decision on whether the experiments should continue after 1999 has yet to be taken.

For the last six weeks, JET has been using a 50:50 mix of deuterium and tritium fuel. When the fuel is confined inside a torus by strong magnetic fields and heated to extremely high temperatures to form a plasma, the deuterium and tritium nuclei fuse to form a helium nucleus and a neutron. A small amount of mass that is lost in the reaction is converted into energy. On 22 September, JET set a new world record for fusion by achieving a 12.9 MW output – 60% of the input power. The experiments continued as Physics World went to press. “We hope to get more power, ” says Martin Keilhacker, director of JET.

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