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Journal of Scientific & Industrial Research Vol. 58, September 1999, pp 729-744
SCI-TECH UPDATE
Chemical industry adopts alliance with information technology
Information technology is having its stamp in almost every human endeavour. You name any activity and IT has its presence or scope if it is not tapped yet. Chemical industry is no exception. Things are changing fast in chemical industry and companies are having to learn the lesson that IT is not a back- room function, divorced from real business decisions, but a critical part of a modern competitive company. It requires imaginative and intelligent alliance of business strategy with IT- for improving customer value and service. The key to success li es in how well companies link their IT so luti ons to business strategy.
How companies can take advan tage in adopting IT for their benefit is refl ected in the CSC supplement September 1998 presented with European chem ica l News in which CSC and SRI working together have coll aborated in several areas around the chemical industry- IT interface .
CSC and SRI pl an to execute consulting projects jointly and develop business applicati ons based on SRI's latest technologies in the areas of collaborati on, intellectual assets and knowledge management, and advanced decision support tools .
Since 1990-91 Du Pont created a Central IT group and taken out 45 per cent of costs, reduc ing its annual spending from 1.2 bn to 6S0m dollars. The bulk of Du Pont IT function was given into an alliance with CSC and Andersen consulting. The deal in which CSC was awarded 90 per cent of its 4bn doll ar, ten-year contract with the aim of helping Du Pont to gain the greatest business value from its IT systems. CSC manages all DU Ponts' global information systems and technology infrastructure, including main frame, mid-range distributed computirig, te lecommunicatinns , and cross-functional services. CSC' s chemical and energy services are organised in 5 categories: New technologies: Business process out sourcing; Technology management ; Systems integration ; and Management consulting.
CSC has been given the responsibility for provision of
globally integrated IT services to DuPont. CSC operates
DuPont's global information systems and teChnology
infrastructure, in addition to providing chemical business
solutions designed to enhance DuPont's manufacturing,
marketing, di stribution and customer service in Canada
and Europe, which includes being the primary, global
ERP solution provider with SAP. Over 200 chemical
experience SAP people moved to CSC as part of the
alliance.
The decision to divest its medical subsidiaries trig
gered the issue of an IT alliance in the middle of 1995,
Impressed upon the degree of added value that.CSC has
brought to their business, DuPont entered into the al l iance
with CSc. DuPont decided in 1996 to have an all iance
with CSC, with Andersen Consulting bringing in its experti se.
The alliance has made progress in a number of key
areas. New Skill s have been brought to bear in the areas
of SAP, year 2000, supply chain, applications and soft
ware engineering. CSC has made progress by mobili sing
a team of specialists to support year 2000 initiatives and
has focu sed on improving desktop service and response
time for users throughout DuPont.
Under the new set up, the DuPont strategic business
units buy in the IT services they need from the all iance
partners. DuPont is planning to benchmark IT costs
against the other companies and look for savings as the alliance settles in .
It is exploring the possibilities of bringing in Asia-Pa
cific operations within the remit of the a lliance, as well
as to extend to other business processes such as payroll ,
HR, procurement and accounts payable, where there is a
high IT component [Eur Chern News, CSC Suppl , September 1998, 4-5] .
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730 J SCI IND RES VOL 58 SEPTEMBER 1999 SCI-TECH UPDATE
Interdisciplinary il1lstitutes linking physics and biology
Steven Chu, 1997 Nobel Laureate for Physics for his work on the laser-cooling of atoms is collaborating with the biochemist James Spudich on plans to bring together physicists and life scientists in setting up of new interdisciplinary research Institutes. These are to be located at Stanford University , California where 50 full-time academic staff in disciplines ranging from applied physics to clinical medicine work together.
The team is hopeful to raise the necessary funds and is approaching individual donors and granting institutions. They also believe that close co-operation between physical scientists and life scientists makes a great deal of sense as the increasing power and quantitative nature of the life ~ciences requires ever more sophi sticated data-gathering and analytical techn iques that only physicists can provide.
StudIes on genome ana lysis requires complex information to be integrated which requires the talents of biolog!sts , che m is ts , compu te r software and hardware s ecialists. Princeton Uni versity announced that a multi J isciplinary insti tute fo r this purpose. Shirley Tilghman, :::. oioneer in hu man genome mapping and the first director ~ys that the Institute will apply techniques from physics,
chemistry, computer science, mathematics and engineering to "an avalanche of new information in genomics and structu ral biology that poses fundamentally new challenges for bi ologists" .
The Uni versity of Chicago is planning an "interdivisional insti tute" in a separate building with a mix of physical and bioiogical scienti sts.
The Uni versity of Cali fomi a, Berke ley, plans to set up a joint bio-engineering department with the Uni versity of California, San Franc isco--one of the pioneering institutions in the recombinant DNA teGhnology that made modern genomi cs possible . The new department will bring together research proj ects th at are currentl y scattered across several departments, includi ng e lectrical eng inee rin g a nd c omp ut e r s ci e nces, mec ha ni ca l engineering, chemical engineering, physics and chemistry .
As recent studies in b iology are becom ing data-ri ch, there is a g rowing reali zati on that the time is ri pe for physical scien ti sts and engi neers to come together with biological and medica l sci entists.
The new co ll aborati on in these ins ti tutes wi ll not simply be one- way projects .. T here .is a lot more to share
between physical scientists and biologists but physical scientists are realising that they can use biological systems for test systems. Chu and his colleagues are engaged in studies using DNA as a model to study polymers and chu said "we have been able to test several fundamental assumptions in polymer dynamics" [Phys Wrld, 12 (2) (1 999) 7].
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Computer pen that records what one writes developed
Researchers at the BT Laboratories , Ipswich , UK have deve loped a 'computer pen' that stores in its memory what the user is writing. .
The prototype, called SmartQuill, ·is cl aimed to be the biggest revolution in handwriting since the invention of the pen.
The style device, unlike the conventional hand-held computer, has no keyboard . It links to a printer, mobile
. tel ephone, modem or a persona l computer via a speciai e lectronic ink-well , a llowing handwritten notes to be eas ily stored on its hard d isk. It can function as a dia ry, calculator, calender, contacts database, al arm, note taker; and can receive e-mail s and pager messages.
Unlike the Apple Newton, which al so uses a pen, the SmartQuill does not need a screen to work. In reality, the clever bit of the technology is its ability to read handwriting not only on paper but on any flat surface - horizontal or vertical. A tiny light at the tip even allows writing in the dark .
SmartQuill can even trans late invisible writing in the air. Thi s is ach ieved through a unique technol ogy called accelerometer that monitors hand movements and can also be used as a 'virtual hinge' to scroll around the small screen on the pen and detect le ft or right-handed use.
Roger Payne expl ai ns that reduc ing the size of traditional handheld computers can onl y be taken so far before they beco me unusab le . Keyboards become so tiny that one requires need le- like fingers to operate them and screens thal need cons tant cursor controls to read si mple text.
S martQu ill is a co mputer housed with in;} pen which a llows one to do whar a normal personal organiser does, but it is really mobil e becau se of its small er Size and one-hand d use. The pen will be a boon to users writing
SCI-TECH UPDATE 1 SCI IND RES VOL 58 SEPTEMBFR 1999 731
in language such as Chinese which traditional keyboards cannot cope with.
For more information, contact:
BT Laboratories, Martlesham Heath, Ipswich; Tel : 1473606552; Fax :1473 606772; Website:www:innovate.bt.comlshowcase/smart quill.
Virtual facility for biodiversity
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With the advent of superior computing facilities backed up by advances in networks, scientific research has attained a new dimension . No longer the scientists need to be at the same place physically present to conduct and converse with their counterparts with the help of "Collaboratory" concept, scientists scattered over all the globe, are communicating with each other, recording their observations, exchanging their readings online through virtual reality systems, video conferencing, etc.
Scientists working with biodiversity have also decided that to better understand the planet'S known organisms, as well as their habitats and ecosystems, they do not need a mammoth physical structure. They are infact advocating for a vast virtual facility that would compile and catalog detailed data sets on the billions of living things scattered over the biosphere.
The conventional practice for scientists in biodiversity field is to send specimens by mail and study them. But adopting information technology, they hope to simplify projects and time by calling up most of the data sets for a species or family with a click of a button.
Already an on-line system called "Natural Heritage Programs" is there in USA. The National virtual facility version called National Biological Information Infrastructure (NBII) was on-line in 1989, with its counter parts in AustraJia and Canada.
Representatives from several countries met to give a final shape to the plan for establishing such a virtual facility called the Global Biodiversity Information Facility (GBIF) at the meeting conducted under the aegis of OECD in Paris. The idea was mooted in 1990s and GBIp· is likely to go on-line in 2000. It is the global version of virtual biodiversity facility efforts that are already present at regional, national , and international levels.
The NBIIs operating around the world will be the first nodes of the GBIF network. In USA, the government will invest 40 million dollars a year for the next 5 years in
upgrading the NBII to what is called NBII-2 to increase the numbe, of databases online, adopt better standards for biodiversity and ecosystem information and establish a system of regional super computer nodes that would enhance data crunching capabilities. Since GBIF and other national, regional bodies have to work together, there is a greater need that certain standards are worked out so that data can be exchanged easily.
The USA and other countries, Australia, Denmark, and the UK have pledged to invest resources for this international venture and are working out to decide where the governing board offices should be located and how much funding each country can muster.
The consortium, at present consisting of industrialized countries, have expressed that once these biological information infrastructures have been established images of all Third World country artifacts and specimens housed in the museum of industrialised nations will be readily accessible. Thus they can use the virtual facility without having vast specimen collections. Steve Young, a computer specialist working on GBIF at the EPA feels that a give-and-take relationship marks the GBIF participation in which the collaborating countries both contribute as well as access data [The Scient, 13 (3) (1999) II].
Website provides Periodic Table
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An on-line Periodic Table is made available by the Royal Society of Chemistry at its ChemSoc website from March 3, 1999.
The Table forms part a visual arts and science collaborative project, known as 109 after the number of officially-named elements that comprise the Periodic Table. The project aims not only to produce vibrant representations of each element but also to investigate the manner in which the elements affect our natural lives. The images will be accompanied by a brief description of the properties and uses of each element. [Chem Brit, February 1999, p.51]
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Techniques use fluorescence · to detect land mines, nerve gas
Fluorescence is the common technique lIsed by two chemist groups for detecting .unexploded land mines at Massachusetts Institute of Technology (MIT) and for
732 J SCI IND RES VOL 58 SEPTEMBER 1999 SCi-TECH UPDATE
se lective ly de tectin g chemical warfare agents , or
nervegas, at the Univers ity of Maryland, College Park .
The MIT group is developing fluorescent porous poly
mer films for dete·cting land mines (J A.rn Chern Soc, 120
( 1998) 11 864). Thei r work focused on sensors for 24,6-
tri ni trotoluene (TNT) and 2,4- dinitrotoluee (DNT), the
main constituents of an esti mated 120 million unexploded
land mines worldwide. The researchers' most recent de
velopment is pent i p~cene derived phenyleneethynylene
polymers ~ hat form spectroscopically stable, highly fluo
rescent th in films.
At present metal detectors are used for detecting land
mines. But Swager of the MIT group feels that they are
not efficient as they produce many fa lse alarms. Also,
dogs are the best detectors of trace vapours of TNT and
its deri vat ives, but it is still a hazardous duty . Other
non-canive methods inc lude neutron acti vation analysis,
electron capture detection, ion mobility spectrometry ,
and biosensors.
But the MIT team is worki ng on a dev ice that is a
real-time NT chemosensory one that not on ly comple
ments existing methods, but also provide the advantages
of low cost with simpli fied instrumentation .
Robert P il ato and hi s co-workers at Maryland have
, eported a way to rap idl y and select ive ly detect volatile
fl uoro and cyanophosphates, the major constituents of
chemical warfare agents [J Am Chem Soc, 120, 12359
(1998)]. The method relies on a !=Iatinum 1,2-enedi thio
late complex with an appended alcohol that fluoresce at
room temperature upon exposure to selected phosphate
esters.
Organosphosphate nerve gases inhibit acetylchol i
nesterase, which control - muscle contraction.
Pilato and his colleagues hink the selectivi ty of thei r
complex promises ·mprovement on current means of
detecting chemi cal warfare agents. To detect the fluores
cence, they have immobilized the material in a cellulose
acetateitriethyl c itrate po lymer that could be used to coat
fiber optics. They tested the system aga inst mimics of
chemical weapons (phosphate esters with vapour pres
sures too low to create a lethal dose (Chem Eng News, 77
(5) (1999) 72].
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Pro~ess for separating mUlti-component mixtures developed
Sumitomo Heavy Industries Co., Tokyo in collaboration with Kyowa Yuka Co., Tokyo, have deve loped a continuous distill ati on process that separates three-component mixtu res in a single tower. The meth od is a variation on the Petl yuk princ iple, which traditi onall y uses a fractionator followed by a single column. Sumitorno's column contains three packed sections-upper, middle and lower. The middle section has top and bottom subsections, and the mix ture is fed in to the space between them.
The entire secti on is div ided by a longitudinal partition, which avoids mingli ng of the feed with the outl et for the mixture's B component, on the opposite side of the column. The A+B frac tion of the feed is enriched in the top subsection of the middle sect ion, then the A component is enriched in the upper secti on before ex iti ng the top of the column.
The B component is recovered from the middle section, oppos ite the feed port, and the heavier C component is removed at the bottom. The company c la ims that the ethy l acetate insta ll ation has reduced energy costs by abou t 30 per cent, compared with a conventional threecolumn system. Construction costs and the installation space were also cut by about 30 per cent. The company adds that the ethyl acetate product-the B component)las a purity of99.999 per cent. The A component consists of lower-boiling impurities, such as acataldehyde, and C is hi gher- boiling impurit ies such as crotonaldehyde [Chem Week, 44 (33) ( 1999) p. 130; Chem Eng, 105 (7) ( 1998)]
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Simultaneous inductively coupled plasma emission spectrometer developed
Varian Analyti cal Instru ments Company has deveioped Simultaneous inductively coupled p lasma atomic emission spectrometer (ICP- AES), which is cla imed to the world' s fastes t ICP-AES. It is based on next-generation charge-couple device (CCD) detector technology. It uses a patented detec tor chip that cah measure 73 elements in 35 seconds and the detector readou t speed is nearly 80 ti mes fas ter than conventional units .
The chip is designed to provide full wavelength coverage from continuous arrays of pixels i.e. photosensitive detectors , rather than grouping pixels in segments to
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SCI-TECH UPDATE J SCI IND RES VOL 58 SEPTEMBER 1999 733
cover selected wavelengths. This allows both trade and major concentrations to be measured simultaneously by alternating wavelengths.
Fast, accurate results are generated from a singleplasma configuration, without having to re-analyze samples. A mapping feature arranges pixels in uninterrupted angled array to match two-dimensional imaging from the thermostatted echelle optical system. It provides full wavelength coverage from 167-785 nm and spectral interferences can be easily eliminated .
High-speed performance enables read out of one mil lion pixels each second. Accompanying software uses a unique worksheet concept modeled on the analyst's workbook. Auto Max determines the optimum conditions for anal ys is when the user presents a sample. Adaptive Integration Technology (AIT) enables intense and trace signals to be. measured simultaneously at the optimum signal-to-back ground ratio .
AIT automatically allocates shorter integration times lessen intense peaks. Quality control protocol with programmable language allows users to meet regulatory requirements. Applications include analys is of organic solvents for chemical industry and monitoring of pollutants and trace elements in effluents, soils and sludges (Chem Week. 44(33)( 1999)p. 133; Hydrocarbon Process, 77(6)( 1998)].
Solar-powered water purification
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NTT, Japan which is a pioneer institution in .telecommunications has special considerations and internal commi ttee" for envi ronmental issues and has a continuous programme to curb the increased use of energy consumption by implementing some measures fo r the reduction of energy consumption and proact ively work on introducing clean energy systems . They have already introduced solar power generation systems and wind generator systems at 29 locations around the country . The cumulative rated generation capacity of these systems has reached approx imately 1.4 MW, which represents the highest level achieved by a pri vate sector company.
So lar power generation systems are extremely important to ensure a power source for telecomm;.mications .
NTT started conducting operation experiment on solar-powered water purifications systems, at two locations , at Shin-Mitsuke moat (joint experiment with the Tokyo Metropolitan Government) from December 1997 and at Mi sugi Park pond Uoint experiment with
Itabashiku) from May 1998. This system, which comes in a disk shape with a diameter of approximately 10m, has a unique floating structure. It uses electric .power generated by solar cells installed on the roof and electric power stored in the power storage equipment for telecommunications when a disaster takes place . Under normal conditions, the power is used for charging the power storage equipment and purification of the water.
With the individual components for the purification process made into units, the system is composed of the following units :
an aeration unit that ejects water including air to supply oxygen into the water for the purpose of improving the oxygen content in water and restricting the generation of hydorgen sulfide which causes an unpleasant smell ; a filtering unit to remove suspended solid matter; a phosphorus adsorption unit designed to remove phosphorus in water to reduce the speed of growth of algae; and a pressure unit des igned to add pressure to the surface water which includes phytoplankton and reduce the proliferating ability of plankton. The two systems for the operation experiment incorporate two aeration units, four filtering units and two phosphorous absorption units. The system set up at Shin-Mitsuke moat has one pressure unit additionally to perform optimum operations. The maximum water capacity processed by each unit is 2 16 tons, 144 tons, 36 tons and 20 tons per day for aeration , filtering, phosphorous absorption and pressurizing, respecti ve ly.
In the energy system, single crystal silicon solar cell s were employed because of their excellent power generation efficiency. The 62 so lar battery panels generate 5 kW at maximum, and annual generated amount of power is estimated to be 6,000 kWh.
As the system set up at Shin-Mitsuke moat moves on the moat within a range of about 40m in diameter, the solar cells were laid in a radial pattern over the entire roof surface so that the system would not be afected by changes in the direction of the sun light. The system at Shin-Mi tsuke is made to move on the surface of the moat to purify the water usi ng the ejection pressure of the aeration units as driving force.
In contrast, the Mitsugi Park pond, running about 100m in diameter, is almost entirely closed with onl y the inflow of spring water. The system installed at the Mitsugi Park pond was strucured in a way to ensure safety so that it can be used as teaching aid for environment and multimedia technologies. More spec ifically, the system enables children to actually enter inside the system and
734 J SCI IND RES VOL 5&. SEPTEMBER 1999 SCI-TECH UPDATE
to compare the water quality before and after the purification process.
On obta.ining satisfactory results from these two sites, NIT plans to promote further exdperiments at other lakes and marshes around the country. This may also create opportunities for new environmental businesses [NTT Rev, 11 (2) (1999) 65-68).
Single photon generatoar device
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A novel device for ~rierating single photons has been reported by three groups at stanford University in the US, Hamamatsu Photonics in Japan and NIT Basic Research Laboratoaries, Japan [Nature, 397 (1999) 500].
To make a single-photon source it is necessary to convert single electron-hole pairs into single photons in an orderl~ manner. In a capacitor, when the charging energy, e 12C, is larger than the thermal energy of the electrons, any further random drift of electrons into the capacitor is suppressed. Basically this is what Yamamoto and colleagues did - they build a device that could allow just one electron or hole into the device at a time.
Since the voltages with which they had to work is of the order of 10 femtofarads, the researchers etched pi liars just 200 nm wide in a layered semiconductor structure. Each pillar contained three gallium arsenide quantum wells sandwiched between a negatively doped aluminium gallium arsenide (AIGaSs) layer on one side and a positively doped Al GaAs layer on the other. There were also thin AIGaAs layers between the three quantum-well layer. The band gap between the conduction and valance bands is smaller in gallium arsenide than it is in AIGaAs, which means that charge carriers (both electrons and holt!s) tend to be trapped in these layers. The devices are cooled to 50 mK in a dilution refrigeratoar to ensure that the then:nal energies are below the single-electron chargIng energy .
The two outer quantum wells act as resonant tunnelling barriers to the holes and the electrons, which can recombine in the central quantum well to produce a photon.
Yamamoto and co-workers demonstrated that their device was emitting single photons by showing that the emission times of the photons were strongly correlated with the electron and hole injection time. They went on to show that two electrons and two holes could also be introduced per cycle, and thus they were able to create a regulated stream of photon pairs.
The Stanford-Hamamastu-NTT device is the first demonstration of a "single-photon turnstile device", and is based on a design first proposed by Atac Imamoglu and Yamamoto in 1994. The current version suffers from an extremely low quantum efficiency (only I in 10,000 of the electron-hole pairs lead toa detected photon) and, of course, its operation at 50 mK is a little impractical for real appl ication [Phys Wrld, 12 (4) (1999) 19].
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Dfanodic PLUS cooling water treatment system
Betz Dearborn has developed "Dianodic PLUS" cooling water treatment, which is able to proteqt cooling water equipment against corrosion, scale, and fouling. The unique system does not degrade in the presence of bromine, chlorine or other-halogen-based oxiders commonly used to control microbiological growth.
Scale control agent, typ:ically used as organic phosphate materials that are destroyed by chlorine and bromine. Unlike conventional treatment systems, the new technology is unaffected by chlorine or other halogens, thus scale and corrosion protection does not break down. The treatment is a halogen- stable copper corrosion inhibitor. Copper alloys are widely used in cooling systems due to their excellent heat transfer properties .
Azoles are used to protect equipment from corrosion, but are degraded by the halogens-bromine and chlorine-thus reducing their effectiveness. The unique chemistry of the new technology provides a protective corrosion inhibitor film on the copper'and copper-alloy heat-exchangyr surfaces and are unaffected by halogens . Because dissolved copper levels are reduced, steel surfaces are also protected against galvanic reaction between steel and products of copper corrosion. Two chemical systems are available-Dianodic PLUS alkaline is a patented halogrn-stable, non-phosphorous calcium carbonate inhibitor for scale and corrosion protection. Dianodic PLUS neutral pH technology uses a blend of unique, halogen-stable polymer dispersants that c;:an be customised for specific water cool ing conditions [Chem Week, 44 (33) (1999) p. 131; Hydrocarbon Process, 77 (7) (1998)).
New sludge pretreatment process
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Sludge dewatering specialists Simon-Hartley and Norwegian thermal engineers Cambi have developed a new
SCI-TECH UPDATE J SCI IND RES VOL 58 SEPTEMBER 1999 735
sludge treatment process at U K. The process, currently being installed at Thames Water's Chartsey treatment works in Surrey, uses thermal hydrolysis to disinfect sludge prior to disposal to agricultural land. Over half of the million tonnes plus of dry solids sludge produced annually in U K currently goes to agriculture, with this figure estimated to rise to 900,000 tpa by 2002. The Cambi thermal hydrolysis process is claimed to be more effective than the biological hydrolysis that normally occurs in digestion .
Hydrolysis sterilises the sludge, so that the methanogenic bacteria active in the digesters are not disturbed by . varying bacterial content of the incoming sludge. The patented new technique utilises direct steam injection to
heat the sludge to 130°C at residence times of around 30 mIn.
By providing consistent temperatures and pressures in the process, the system is said to produce ideal feed sludge fo r anaerobic d igestion. The result is that bioges production from the diges ters can be increased to the extent that the Cambi process could be run entirely on recycled energy from a CHP system powered by the biogas . The Cambi process is being retrofitted into Chertsey where a cental ised treatment centre handles sludge arising from six different locat ions [Chern Week, 44 (33) ( 1999) p. 13 1; Process Eng, 79 (7-8) ( 1998)] .
Carbon nanotubes create a nanobalance
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Researchers at the Georgia Institute of Technology have used the bending properties of carbon nanotubes to create a nanobalance. They app lied an electrical potential to nanotubes protrudi ng from a carbon fibre that, in turn, was attached to a fine gold wi re . They then brought the tubes to wi thin a few micrometers of oppositely charged electrode, and put the assembl y in an electron microscope. When an oscillating vol tage was applied, a given nanotu be cou ld be made to vibrate resonant ly , even at rhe second harmonic at 3MHz for a mu ltiwalled tube
6.25 IJ-m long and diam 14.5 nm. A particle attached to he tip of such a nanotube would change the re"onant fr~quency, enabl ing researchers to deduce the mass of the p'rtic!e. The researchers weighed a 22-femtogra ln gr,~ hite particle in this manner [ Ph),s Today , 52 (5) ( 1999) p. 9 ; Science, 283 (1999) p. 15 13] .
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Fuel stabiliser for combustion processes
Custom Alloy Corporation has developed an inset fuel stabiliser which offers unique benefits for combustion processes . When installed in th~ fuel line close to combustion equipment, the fuel stabiliser aligns fuel molecules and "stabilizes" them. These fuel molecules will then burn completely in the combustion chamber. The process is claimed to achieve nearly 100 per cent combustion , thus eliminating carbon monoxide, hydrocarbons, particulates, sulphur dioxide and nitrogen oxides in the exhaust. The technology can be used on many fossil fue ls such as - gasoline, diesel, propane, kerosene, natural gas and fuel oil.
A more efficient combustion process reduces exhaust pollutants. This facilitates compliance with stringent ai r regu lations and el iminates post treatment of exhaust gases. More efficient fuel consu mption allows usi ng lower fuel grades to achieve the same results and reduce boi ler maintenance. Fuel efficiency can be boosted from 6 to 30 per cent depending on the application. Optimum combustion eliminates carbon deposits in the boi lers heating box, thus lengthening equipment run length and reducing maintenance. Process applications includeboilers, co-gen turbines, diesel engines, f ired heate rs or the fossil-fuel burning equipment. The uni t has no moving parts, uses no electromagnets, additives, catalysts , filters or dissimilar metals [Chern Wk, 44 (33) (1999) p. 13 1; Hydrocarbon Process, 77 (7) ( 1998)] .
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Women's exposure while workin·g with organic solvents during pregnancy cautioned
Sohail Khattak and his team, of the Hospital for Sick Children, Toronto" Canada, have warned that women should avoid working with organic solvents when pregnan t. They found that pregnant women exposed to solvents at work were 13-times more li kel y to develop foeta l abnormalities. Whil e animal studies and reviews of medical records have linked solvent expo ure to birth defects , Khattak says, this study is the first to fo ll ow human mothers through pregnancy.
Khattak ' s team tracked 125 women who worked wit h crganic solvents in the first three months of pregnancy . The women mostly worked in clothing or textile production or as laboratory tech nicians . It was found tha t in thirteen of these women . the babies developed major foetal abnormalities incl ud ing deafness. spi na bi fida and malformed Jimb~ . In a marched contro l group of 12:i
736 J SCI IND RES VOL 58 SEPTEMBER 1999 SCf-TECH UPDATE
women who did not work with so lvents, only one suffered similar problems_ Of the thirteen women in the first group, twelve reported symptoms associated with solvent exposure, including eye irritation, breathing difficult ies or headaches_
Khattak admitted that more studies will be needed to confirm the findings, he said it would be prudent to minimise women 's exposure to organic solvents during pregnancy. He also recommended that ventilation and protection at work should be improved. Organic solvents commonly encountered at work inc lude aliphatic and aro mati c hyd rocarbo ns, phenols, tri chl o roethyl ene , xylene, viny l chloride, acetone, and related compounds. Many of these can pass through biological membranes , including the placenta [Chem Ind, No 7 ( 1999)p.248 ; J Am Med Assoc, 281 ( 1999) p.11 06]
New G-seat for flight simulators
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David Burgoyne and his team at Cranfie ld Aerospace in England have developed the new G- seat as a simple and cheap a lternative to the huge hydrau lic, box-on- moving-stills design found in most fli ght simulators today . Fighte r pi lots in a future Gulf War- type engagement could "fly" practice sonies in small , portable flight s imulators outfitted with a motion-mimicking G-seat. To give the pilot the feel of "pulling Gs", an array of electric motors in the Cranfield Aerospace Moti on Cue Seat (CAMCS) lowers the seat. hardens its cushi ons, and slackens the pilot ' s shoulder and lap harnesses. Burgoy ne says that thi s makes the pilot fee l heav ier.
To mimic negative G force, the seat is raised, the cushions softened, and the shoulder and lap be lts tightened-givi ng the pilot the sensation of pitched up. Other mot ion effects i.e. turbulence, buffet ing: runway rumble, and even the jo lt of gunfire can also be generated in the seat.
Not only is the sys tem cheaper to build and operate, it is also much faster than larger motion platforms. Burgoyne says that it can give the pilot in stantaneous onset cues- within 20 milli seconds. Thi s allows to fine ly tune the moti on characteristics to a spec ific aircraft, i. e., an F-16. It can be called "seat-of-the pants" feel .
Burgoyne claims that portability is the G-seat's greatest advantage. Compact CAMCS simulators could be transported on an ai rcraft carrier or to a desert air base
and used to practice last-minute miss ion scenarios just hours before launch [Pop Sci, 254 (5) (1999) p. 36] .
Smart studs to mark road lanes at night
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Drivers, at present, are guided by the familiar catseye reflectors fixed on the road lanes for safe night driving. Astucia, a company in Retford, Notting-hamshire have developed Intelligent Road Studs containing sensors that allow them to detect icy, wet or foggy cond itions .
Traditional re fl ec tor Catseyes are vi sible upto 80 m ahead. Dri ving at high speed, this is not enough to warn a dangerous bend . The studs des igned by the company are fitt ed with solar- powered li ght em itting diodes (LEOs) in stead of sensors. The striking difference in thi s des ign is their ability to communicate with eac h other usi ng infrared (IR) beams. They can be set to change colourto warn drivers of hazards detected by stud s fa rther down the road .
One hour 's exposure to day li ght provides enough power to keep the LEDs going throu gh the night. The range for the vis ibil ity is now extended to 900 m as compared to the tradi tional catseye reflectors in the new studs. They can be programmed to il lu min ate more LEOs in fog, increasing each stud 's bri ghtness .
The new studs can be set in several modes . Instead of being constantl y illuminated , for instance, they can be programmed to flash on for 4s when a passing car breaks an IR beam shin ing ac ross the road between a pair 0
studs. Thi s creates an impress ion that the car ahead is leavi ng an illuminated trail. The studs can be made to change colour to warn a car following too close behind the one in front to keep to a safe braking di stance. Police traffic controJ cent res also get useful in fo rmati on about road conditions from these studs . They are like ly to be installed at acc ident black spots 111 Britain earl y 1999 [New Sci, 160 (2 160) (1998) 24].
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Approaches of techniques for arsenic removal from drinking water
Environmental Protection Agency (EPA), USA has determined that exposure to high levels of arsenic to increase the risk for skin cancer but it has not quantified an increased ri sk of mortality fro m arsenic-induced li ver. kidney, lung, or bladder cancers. Data also suggest that
1
SCI-TECH UPDATE J SCI IND RES VOL 58 SEPTEMBER 1999 737
arsenic may affect the vascular system in humans and may be associated with the development of diabetes.
The current drinking water standard for arsenic is 50 g/1. University of Connecticut (Storrs) assoc iate profes-
,r of civil engineering Nik Nikolaidis, developed a new I.echnology called AsRT technology with Jeff Lackovic, a doctoral candidate at UConn, and Greg Dobbs, a senior consulting scientist with the United Technologies Research Centre which is more cos t-effective than traditional methods at removing arsenic to below a detection limit of I g/1.
US Researchers are e ngaged with inves ti gat ions in finding out whether the U.S. drinking water standard is too high. The EPA is expected to issue a new proposed standard for arsenic in drinkin g water by January 2000; the World Health Organization recommends a standard of 10 gil.
The AsRT technology can be used to c lean ground water, surface water, and wetland sediments contaminated with arsenic , accordin g to the AsRT developers . Its onl y drawback may be a net export of iron from the iron filings used in the treatment, which may require further remediation , although thi s drawback is not an issue in groundwater or surface water systems where the iron can be r "idized and prec ipitated out of the water.
In field tests, groundwater containing 300-400 g/ I is pumped, bottom to top, through a tube filled with the sand-iron mi x at a rate of about I gal per minute . As of late July 1998,380,000 I were processed resulting in less than I g/ I of arsenic e ffluent , according to Nikolaidis. The team' s findings are available on the Internet at http://wws.eng2. uconn.edu/-nikos/asrt-brochure.html.
Coagulation/filtration , the standard treatment for remediating arsenic and other contaminants from surface water, uses iron , which reacts with arsenic to create a sol id that prec ipitates from the water. Jeff Kempic, team leader for treatment techn ology in the OGWDW, says coagulation/filtration can re mediate arsenic to levels of 2-5 gil , but doing so requires more coagulate or using a different coagulat~ . "It's not dramatically expensive to remove more arsenic in a coagulation/filtration system," he says, "if the treatment plant is already in place," However, this treatment system produces an arsenic-contaminated sludge that might need to be disposed of in a hazardous waste landfill if the EPA lowers its arsenic :-, \,mdard. One advantage of the AsRT treatment is it involves a smaller waste stream than traditional approaches, because most of the arsenic removal occurs on the surface of the iron filin gs and sand in he filter, and
this mixture of iron and sand should be usable for several years, depe 11 ding on conditions at a particular treatment site.
The othe r technology anion exchange is also effective for removing assenic, but has some disadvantages. A lthough effective in re moving contaminants to be low 2 gil, reverse osmosis is a more expensive technol ogy than coagulation/filtration and produces a brine that mu st be treated for arsenic contamination. Moreover, reverse osmosis produces a larger waste stream than other treatment.methods, which may make the method impractical where water is scarce .
Achievinga lower arsenic standard requires the insta llation of a treatment system for groundwater that presently is simply chlorinated , according to Dennis Cl iffo rd , a professor of environmental eng ineering at the Uni versity of Houston in Texas. Coagulation/filtration requires large settl ing tanks and presents some prac ti ca l probl ems.
A modified version of the coagulation/fillrati on process has been tested in Albuquerque, New Mex ico . This approach uses traditional iron coagulation, but employs a vigorous II)-to 20- second mixing process, after which treated wakr is passed immediate ly through a membrane filter with a pore size of 0.2 microns or less . Passage through the membrane filter immediate ly removes arsenic, which e liminates the need for large settling tanks and enables water systems to produce water as demand requires it.
The appropri ate treatment approach will depend on a particular water system's needs, resources, location and other factors.
The American Water Works Association (A WWA) says that the "biggest hang-up we have is that the sc ience is not there yet to justify lowering the standard". The main concern, one of its engineers says is what level of exposure produces the health effect s .
Allan Smith , a professor of epidemiology at the University of California a Berkeley, says no data ex ist to prove or disprove that arsenic produces health effects at or below a threshold level of exposure. He therefore believes thai arsenic standard of 10 gil should adopted at least as an illterim standard without waiting on scientific proof of exact levels of ri sk, which he believes be extremely difficult to obtain [Environ Hlth Persp, 106 ( II ) (1998) A 548-A 550].
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738 J SCI IND RES VOL 58 SEfYfEMBER 1999 SC I-TECH UPDATE
Airborne airbags protect passengers
AmSafe, the world 's larges t producer of ai rcraft c eat be lts in Mesa, Arizona, has developed first airborne airbag to protec t passengers. AmSafe has des igned the airbag to help airlines meet new safety standards and to reduce injuries in survivable accidents . The Federa l A viati on Admini st ration wants new aircraft to protect the ir occupants aga inst a \ 6-G longitudinal deceleration , of the sort that might be experienced in a severe crash landing. Lap be lts and stronger seats with co ll aps ible backs will meet thi s requirement for most passengers, but travelers seated in bulkhand rows need a sys tem that will prevent the ir heads from striking the bulkhead. Thi s is (k; primary role of the AmSafe airbag.
The bag is folded into a sheath on the sea t belt, and is almost undetectab le to the passenger. A hose connects the baa to a control unit beneath the seat, which contains b
propellant and mUltiple G-sensors. In the event of an accident , the bag inflates outward , away from the passenger, so airbag-related injuries of the kind seen in cars will not occur.
AmSafe says that its tests have shown that , for a passenger in a bulkhead seat, a bag deployed during a \ 6-G crash reduc~s head injuries from an invariably fatal level to a level at which the passenger should remain conscious and be able to escape from the aircraft [Pop Sci , 254(5)( \ 999) p.32]
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New type of medical device for, diagnosing diseases and counting red blood cells found
A new type of medical device that can diagnose discases and count red blood cells si mply by shining a harmless laser on skin has come up to replace blood test which is painful. Mark Samuels of Georgia company, SpectRx , has developed a device, called BiliChek, capable of diagnosing infant. jaundice by shining light on a baby's forehead. The device, which does not require a needle could replace a standard blood test that is commonly used to test infants for jaundice before they are discharged from the hospital.
Infant jaundice is caused by a baby's temporary inability to process the protein bilirubin, a byproduct of dying red blood cells. Up to 65 per cent of all newborns worldwide are affec ted with some degree of jaundice, experts estimate. In the most severe cases, the buildup ofbilirubin can cause brain damage or death is left untreated.
The new dev ice ca lcu lates the amount of bilirubin present by analys ing the spectrum of light that is reflec ted back from blood ce ll s beneath the infant 's sk in .
SpectRx has a lso developed a prototype of a s imilar device that measures g lucose leve ls in the bloodstream, and is working on a thi rd device to detect malignant cancer cells. In add ition, ot her companies, such as Philade lphia-based Cytometrix, are in the proce s of developing s imilar nonin vas ive products that can count red blood ce ll s and measure hemog lobin leve ls almost instantaneously [Pop Sci 254 (5) ( 1999) p. 34].
Bacterial process to remove toxic meta ls
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Researchers at the University of Dundee, Scotland , have des igned a linked system that allows two types of so il bacteria to work in tandem to remove metal s in contaminated so il s. In this process , sulphur-oxidising bacteria leach heavy metal and su lphur-reducing bacteria immobilise or precipitate metals. In nature, these bacteri a remove toxic metals separately, but they tQke many years to produce a noticeable effect.
For more rapid remediation to take place, the combined acti vi ties of both types of bacteri a are needed, but it has not been possible to use sulphur-oxidisi ng bacteri a and sulphur-reducing bacteria togethe r because the i ~ respective environments are inhospitable.
By designing a feedback reactor that contains two compartments, one for oxygen-loving and the other for the sulphur-reducing bacteria , the researchers have been ab le to clean up contaminated soi ls much more quickly. The integrat ed reactor separates the sulphur-oxidising bacteria in a bio-Ieaching tank from the sulphur-reducing bacteria in a bio-precipitation reactor, while letting the process continue sequentially under continuou s-flow conditions . In a demonstration, soil taken from an industrial site that had been contaminated with toxic metals was leached so that 69 per cent of the metals present at the outset were removed [Chern. Week, 44 (33) (\999) p. 132; Chern. Eng Process, 94 (7) (1998)] .
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Treatment used to prevent heart attacks found to be effective at lowering stroke risk
Michael Marks and his colleagues at the Stanford University School of Medicine, USA have found that a
SCI-TECH UPDATE J SCI IND RES VOL 58 SEPTEMBER 1999 739
technique traditionally used to prevent heart attacks may prov ide new hope to people suffe ring from repeated, debilitating pre-stroke symptoms. By inserting miniscule infl atable devices into partia ll y blocked arteries in tlie brain , they are ab le to gentl y st re tch the vessel wa ll s and increase blood flow to oxygen deprived regions. T he procedure can allev iate transient ischemic attacks, which freq uentl y signal an imped ing stroke, and decrease the likelyhood of permanent neuro logical damage.
In this new study, more than 90 per cent of the 21 patients treated responded favourably, resulting in a marked decrease in the group's annu al rate of st rokes over a three-year period .
Not onl y has there been a low rate of stroke, but none of the pa tients that au thors were aware of so fa r have had repeated symptoms of transient ischemic attacks. It is be li eved thar the res ult s of the new intracra ni a l angioplasty treatment are promising enough to require a contro ll ed study compari ng its success with traditi onal medicati on for stroke-prone patients.
In the present study, a group of patients whose symptoms were not a llev iated by medication were selected for the new angioplasty procedure. The workers used catheters and guide wires to direct the uninflated balloons from tile fe moral artery in the hip to the sight of the blockage in the brain. Once in place, the balloons were slowly in flated over a peri od of about 30 to 45 s to about 2 to 4 mm, a diam somewhat smaller than the surrounding, unblocked reg ions. The balloons were then deflated and withdrawn.
T he procedure is des igned to basically crack or injure the atherosclerotic pl aque and have it heal in a more open fas hi on. A more open artery results in more blood fl ow to the brai n.
The technique helped decrease the degree of blockage from 9 1 to about 40 per cent in 22 of the patients studied.
After the angiop lasty procedure, the patients were monitored for an average of 3y to determine the ex tended benefits of the treatment. All o f them remained on medication during the follow- up period. Three years after treatment , the group' s annual stroke rate was 3.2 per cent for strokes occuring in previously blocked region, and 4 .8 per cent for all strokes. That compares to an expected 8 to 10 per cent chance of strokes for patients treated with med ication alone.
Marks emphasized that the patients may have had an even higher risk of stroke before treatment because their symptoms continued desp ite medication . After the treat-
ment, however, most patients experienced significant improvement in their overall health .
One of the most rewarding experiences was that a group of patients that were having repeated symptoms despite medication, some of whom were litera ll y bedridden, experienced compl ete re i ief from symptoms of transient ischemic attacks.
Balloon angiop lasty has become an accepted way to , treat blockage in arte ri es near the heart or in peripheral
arteries feeding the limbs. But using the ba ll oons to treat blockage withi n the brai n is still re lati ve ly new. Researchers had to redesign the balloons to be more easi ly guided and tracked during their longer trip from the hip to the brain before they cou ld be used ins ide the cranium.
The treatmem is sti ll usuall y used on ly for vessels at the base of the brain.
This is the first study thal has looked at outcome over a longer term fo ll ow-up . Othe r studi es have focu sed on smaller group~ of pat ients over shorter duration. It is emphas ized LI-.Jr the procedure is most appropri ate for people wi th specia ll y severe symptoms [Storke , May 1999].
Painless hypodermic needles
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Amit Lal of the Uni vers ity of Wisconsin in Mad ison, has built a painless hypodermic need le which could be one of the firs t surg ical devices made using a technique borrowed from Computer chip makers. Lal predicts that by using extreme ly sharp instmments that vibrate at ultrasonic frequencies it will be possible to make incisions that cause hardly any pai n.
With a normal cutting tools, pain is thought to arise because of ti ssue di stress caused by chafing of the tool's edges . But Lal says that by vibrating the tool at an ultrasonic frequency reduces these forces and e li minates the pain.
Ultrasonic cutting tools like thi s have been used for cataract surgery for some years, but they are expensive and prone to overheating. Lal claims that his de vices would be much cheaper and more robust. His idea is to etch surgical devices from silicon wafers, using the same kind of photolithographic techniques that are used to make Computer chips.
Lal says that this proven technology allows to create tools with microscopically fine detail, making thcm tcn times as sharp as traditional scalpels . It is thi s sharpness,
740 J SCI IND RES VOL 58 SEPTEMB ER 1999 SCI-TECH UPDATE
and the fact that hi s devices are vibrated eight times as fas t as conventi ona l ultrasonic cutting tools, that is the secret of a painless cut.
The need les cou ld be a godsend to peopl e such as d iabeti cs for whom ijec tions are part of daiiy li fe. So far the too ls have onl y been used on dead chi ckens, beef and potatoes. Lal adnl its that so fa r on ly tissue has been cut in the lab but any animal or human tests have not been done. He says that in future, another bonus of usi ng s ilicon will be th at sensors could eas il y be built into a tool , in tegrating it wi th a computer and expl oiting the materi al's e lec tronic properti es [New Sci, 162(2 182) ( 1999) p.22].
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Radioactive glass microspheres for treatment of liver cancer
A cancer therapy already in use in Canada has begun c linica l trials in USA in which radioacti ve g lass microspheres are inj ected d irectly into d iseased areas.
The treatment is find ing success in fighting li ve r cancer. Surgery is rare ly used on li ver cancer because mult ipl e tumou rs are sca tte red th roug h011t the o rgan . Chemotherapy may prov ide temporary reli ef but the disea~e may flare up again.
Try ing ex tem ai rad iati on on li ver shou ld be g iven in !fl rge doses and can cause excessive damage to healthy ti ssue around the organ. For example, nea rl y 10 treatments over a 30-day peri od may de live r a total dose of 2000-2500 rads. Thi s is not complete ly effec ti ve . But radioacti ve microspheres injected in to the li ver safely deli ver an average dose of ! 5000 rads in one treatment wi th mill imal damage to healthy su tTounding tissue. T he l1l icrospht:res are on Iy about one th ird d iameter of a strand of hair, and there are very few side effects. Afte r the rad ioactiv ity d isappears after abou t fo ur weeks, the mi crosphcres remain h::m nless ly in the liver.
The treatment may be used for other cancers, such as brain tumours , where surgery or traditionai rad iation treatments presen t e xtraord inary ri sks (Am Ceram Bull, 78 ( 1) (1999) 28·-30]
Male contraceptive pili developed
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Fred Wu and ~10l·to n H air of the Manchester Royal Infirmary, UK, in preliminary trials at a U K hospital have
shown that the problem of produc ing an effect i ve, reversibl e, and conveni ent male contracepti ve pill has been solved .
The new treatment combines the fema le sex hormone progesterone in oral pill form with the male hormone testosterone de li vered via an innovative skin patch.
Progesterone and testosterone have long been known to suppress spe rm produ c ti o n bu t up to now the tes tostorone has had to be admin istered by inject ion. A better del ivery method, such as a skin patch, woul d make it eas ier for men to go on the pi ll .
A signi ficant number of women are unable or unwilling to use the female contracepti ve pill for long- term . T his method may a llow their partners to take the respons ibility for their cOllltraception.
Wu and Hair tried the treatment out on 23 vo lunteers, d ivided into groups taking high- , medium-,and low-progesterone pill s. After three months of treatment , most of the hi gh-and med ium- dose men had no active sperm producti on. When they stopped takin g the pill , their sperm counts retu rned to normal.
The combination works because progesterone te ll s the pituitary g land-the mas ter switch of the hormone system-to turn sperm production off. The testosterone patch is added to counteract progesterone's side effec ts. The hormone swi tches off natural produc tion of testosterone, heading to loss of sex dri ve and phys ical weakness [Chem Ind, No.8 ( 1999) p .. 287].
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Mechanism involved in causing colon cancer found
Weizmann Institute, Israel researchers have d iscovered a molecular mechani sm that may be invo lved in causing colon cancer.
The work may contribute to the development of potential therapies for thi s type of malignancy and possi bl y fo r other types of cancer as well.
The di scovery of the new mechani sm has solved two seemingly unrelated molecular mysteries . One concerning an important finding made some two years ago: the fac t that colon cancer cells often have abnomlall y large quantities of a protein called beta- catenin. Beta-catenin has been dubbed a "moonlighter" because it hold s down two distinct cellular jobs. In its better-known task, betacatcnin binds to adhesion molecules-those molecu ies that si t in the cellular membrane and al low cells to stick
SCI-TECH UPDATE J SCI IND RES VOL 58 SEPTEMBER 1999 741
together. In its other role, beta-catenin is known to regulate the performance of genes in the nucleus.
The second molecular mystery centered around the gene cyclin 0 I-)a major regulator of cell growth which, when mutated, can act as an oncogene, or gene that causes cancer. The levels of the protein produced by thi s gene are abnormally high in abou t 30 per cent of colon cancers, indicating that cycl in 01 may be in volved in malignant transformation. However, the cyclin 0 I gene found in colon cancer cell s is perfectly normal. This baffled researchers because usually oncogenes cause cancer only when they appear in mutated form .
Prof. Avri Ben-Ze'ev et (II. of the Weizmann Institute's Molecular Ceil Biology Department, in collaboration with Dr Richard Pestell ef al. from the Albert Einste in College of Medicine in New York , have now put these two mysterious puzzle pi eces together.
In a test-tube study, the sci ent ists discovered how both beta- caten in and cyclin 0 I are invol ved in causing co lon cancer.
First, the levels of beta-cat en in increase to excessively high levels in one of two different scenarios. In one case, the beta- catenin gene itself is mutated. In the second case, a mutation is found in adenomatous polypos is coli (APC), a well-known tumour- suppressor gene that is mutated in about 90 per cent of colon cancers. APC's major role in the ce ll is to reduce the leve i of beta-catenin. When the APCgene is mutated, beta-catenin accumulates to high levels and enters the nucleus.
Upon entering the nucleus, beta-catenin can directly aCfiv ate the cyclin 0 I gene, lead ing to an abnormal surge in 'he proulk,tion of the cyel in 0 1 prote in. Since cyclin o I is a muj or regu lator of ce ll growth, the result is unccntrollcd cell proliferation. This contributes to abnormal tissue growth and the creation of a tumour.
In most cases, tumour fonnati on is triggered by mutated genes. Therefore, it was unclear how completely normal copies of the cyclin D I gene cou ld be in volved in colon cancer.
Now Ben-Ze 'ev el ai. have shown that the 'gui lty' mutation does not have to appear in cyclin 01 itself, but may be found in mher molecules by which it is affected .
As for beta-catein, researchers for long wanted to know what kind of s ignals it conveys to the nuclei of can..:er cells . The study has made it pos:;ible to 'eavesdrop' on one of these signals, a!lu to :,how how certain colon cancers may develot'.
Ben-Ze'ev and his colleagues have also demonstrated how this signaliilg mechanism can be blocked, a finding that may some day be of use in the development or cancer therapy . In one approach, cyelin 01 activity was diminished by introducing a non mutated copy of the tumoursuppressor APC gene into colon cancer cells . The "good" APC lowered beta-catein levels, stopp ing the abnormal stimulation of thecyclin 01 gene.
In another experiment, they introduced an adhesion mo lecule ca lled cadherin into colon cancer ce ll s. Cadherin is known to bind with beta-catenin at the outer periphery of the cell. Through this binding acti on, the cadherin "trapped" beta-catenin. preventing it from trave lling to the nucleus and excessively stimulating the production of cyc lin 01 protein .
These types of intervention may provide the bas is for developing future therapi es for colon cancer, as we ll as for melanoma and other types of cancer in which the levels of beta-catenin are abnormally e levated [Pro Nat! Acad Sci, USA, 1 I May 1999].
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Combination of medication and psychotherapy produce significant improvemen t in chronic depression
According to Prof. Alan Schatzberg and hi s colleagues at the Stanford University School of Medicine and Marti n B Keller of Brown Uni vers ity School ofJ\iedicine, a new combina tion of drug therapy and a specific form of psychotherapy has produced sign ificant results in treating long-term depression.
While the psychotherapy alone or the l se of the study med ication alone can produce succes~ ful results the added value of the combination treatment produced s ignificant results - faster and . more successful improvement than anyone has ever heard about from a depress ion study .
A total of 68 1 pat ients who had suffe red from depression for two years or more were selected at 12 academic medi cal centers nationwide for the 8-weclc study. About 80 patients 'i','e re in the Stanford group.
Results from the acute phase of treatment - the first 12 weeks - showed that the combination of the study dmg nefazodone and psychotherapy produced significant benefit in 85 per cent of the patients, as m~asured by a common scale used to evaluate depres~ion. The drug alone produced 55 per cent rate of success, about the same as the 52 per cent rate for psychotherapy.
742 1 SCI INO RES VOL58 SEfYfEMBER 1999 SCI-TECH UPDATE
The drug is marketed as Serzone by Bri stol-Myers Squibb Co., which sponsored and financed the national
study.
The study shows that use of the drug a lone is comparab le to results found in earlier studi es for other anti depressant drugs. Fu rthe r studi es would need to be conducted to dete rmine if other common antidepressants , including sertra line, imipramine and des iprami ne, cou ld produce the same results when combined with the spec iali zed form of psychotherapy, ca ll ed the Cognitive Behav ioral Therapy fo r Chron ic Depress ion. The psychotherapy invol ves educa ti on to he lp tl:e patient understand emoti onal triggers affect ing hi s or her life . It is yet not known whether other forms of psychotherapy wou ld produce simil ar results.
The study ind ica tes that combination therapies mi ght be of va lue to the 14 milli on people who suffer from chronic depress ion, even though the costs to providers or to individuals are obviously highe r than one fo rm of treatment a lone (Chronic depress ion is defined as depression ex isting for more than two years).
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Neurological maps hold key to how the brain learns and forgets
According to Stanford Univers ity, School of Medicine researchers, who have studied the ow ls in thei r quest to find out how the brain learns and forgets, learning more sk ill s then reverting back to o ld methods requires onl y pulling up the co rrect neuro logical ·map.
By outfitting the ow ls w ith a pair of pri sm eyeglasses that give the m a skewed view of the world , the researchers have been able to analyze how neurons in the ow ls' brai ns adj ust to the confusing new environment .
Sight and hearing are intimately connected in barn owls, so in order to adapt comple te ly to the new off-k ilter visual wodd, the animal has to learn new responses to loca lize the sounds that it hears. It must a lso forget the o!d responses that are no longer appropriate.
In a series o f incremental advances over the last three years, Eric Knudsen et al. have de termined how cell s in the owl's brain learn to respond correctly to sound . It is now reported that they have worked out the opposite side of the equation-how cell s in the owl's brain forget the incorrect responses.
Barn owls, which have a much more sens iti ve auditory sys tem than humans or other animal s, naturally know
how to loca li ze the ir prey. They quickly locate a chirping c ricket or a squeak ing mou se by integrati ng two neurological maps in the ir brain--one based on sou nd , the other on vision . If the owl first hears a sound in its le ft ear, it knows it I~u st turn its head to the left to see the no isy c ritter and scoop it up for lunch. Researche rs ca ll the inherent neurologica! map that the owls use to do thi s, the normal map.
Owls that a re fitted with the pri sm g lasses see a world th at is shifted . An ow l wearing a pair of ri g ht-shi ftin g g lasses sees objects to its left when it is look ing strai ght ahead. A you ng bespectacled owl learns to compensate for thi s altered perception, turning its head to the ri ght to see what lies stra ight ahead. These ow ls have deve loped a new neurol ogica l map that is ca lled the learned map. For an owl to be able to loca li ze the sound correctl y after wearing the pri sms it has to be ab le to forget the o lder map which is not behav iora ll y app ropri ate and foll ow the new map.
Prev ious researc h in the Knudsen lab has shed li ght on how neurons in the ow l's brain learn the new map, but according to Z heng, people knew nothi ng about the mechanisms underl ying the process of forgetting the old map. Zheng and Knudsen focused on the rcx reg ion of the brain, which is a site of aud itory learn ing in the barn owl. This region of the bra in is a lso ri ch in a certa in c lass of inhibitory nerve cell s called GABAerg ic neur~n s. T he researc hers wondered if the norma l map, when it was not appropriate to the owl's s ituati on, was be ing spec ifica ll y suppressed by these neurons. If their theory was correc t, by blocking these neurons the normal map would move to the forefront, replac ing the learned map .
Zheng and Knudsen conducted a series of experiments, whic h confirmed their hypothesis. When the GABAerg ic neurons were blocked , ce ll s in the ow l' s brain that had been showing the learned respo nses suddenly began ro show the normal responses. The results were important because they revealed that the nonnal map had not been lost. The map and a ll its info rmation had remai ned intact, but had been temporarily suppressed, or forgotten.
When the same approach was applied on adult owls whose glasses had been removed, they got a very di fferen t result. One month after they removed the glasses, they blocked the same neurons in owls that had readjusted to
an unadulterated view of the world and were responding normally to sounds us ing the ir normal neuro logical maps. Unlike the unvei ling of the normal map in the previous experiment, however, the learned map di d not emerge, indicating that it was not being suppressed by the inhi bi-
SCI-TECH UPDATE J SCI IND RES VOL 58 SEPTEMBER 1999 743
tory action of the GABAergic neurons. This revea led that the geneticall y contro lled normal map is different from the lea1l1ed map contro lled by experience.
However, the results gave the researchers a new conundrum that they are now working to solve. Knudsen and hi s team knew from the ir previous work that owls reared with g lasses that had subsequentl y beeT' removed could adapt to the g lasses successfull y once again if they were introduced to the adult owl. These adults quickly remembered how to accommodate the zany view of the world that the glasses induced, whereas adult ow ls introduced to the g lasses for the first time never learned to adapt.
So although the lea1l1ed map could not be experimentally brought fo rth by suppressi on of GABAergic neurons , there must be a trace left in the brain that allows the owls to reacquire it . Some portion of that circuitry is still there, but like a radio that can be unplugged or have its volume turned all the way down , the signal is not coming through, Knudsen explained [Science , 07 May 1999] .
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Cancer vaccine using the cytokine interleukin-2 (IL-2) developed
James Mule and his team, of the Department of Surgery at the University of Michigan, has developed a
cancer vaccine based on dendritic cell s which have sub
stantiall y improved the vaccine ' s e fficacy using the cy
tokine inte rleukin-2(IL-2). They have suggested that
future cancer therapies might re ly on expl oiting the natu
ral regulatory pathways of the immune system. The team
had earlier developed a technique in which host dendritic
cells are exposed to tumor celllysates, then re- int roduced
into the host. Because dendritic cells present the ant igens
to T cells to initiate an immune response again st the
tumor, the sc ienti sts reasoned that IL-2-a T ce ll growth
promoter that has already been approved for clini cal
use- mi ght help the vacc ine produce a more robust
response. Tests of new approach in mi ce showed that the
combined vaccine can render the animals im mune to
lethal tumor challenge and cause the regress ion of mi
crometastases in mice with establi shed tumors.
According to James Mule, a phase I trial on the den
dritic cell vacc ine has shown that "small nu mbers of
dendritic cells can prime patients to react strongl y to that
antigen when presented ·by dendritic cells", and that the
cells have low toxicity. Phase II trial s on the combined
vaccine are stated to beg in in the next few month s [Nature
Biotechnol, 17 (4) (1994) p . 317].
o HSDK
Announcements
Conference on Sintering' 2000
Seventh International Conference on Sintering: Sintering Sc ience and Technology Beyond 2000 AD will be held at New Delhi from Febrmll'y 22-25, 2000, organi sed by International Institute for the Science of Sintering in association with Advanced Materials International. The topics to be covered in the conference shall be foll owing:
(i) Sin tering Fundamentals, (ii ) Modelling of Sintering, (iii ) Liquid Phase Sintering, (iv) Microstructu ra l Evaluati on duri ng Sintering, (v) Sintering alld Phase Relati onships, (vi) Properties Des ign through Sintering, (v ii) Hot Presas ing/HIP Processing, (v iii ) Sintering Atmosphere Effects, (ix) Sintering through Nonequilibrium Processes, ex) Sintering of Metallic Materials, (x i) Sintering of Oxide Ceramics, (x ii ) Sintering of Nonox ide Cereamics, (x iii ) Sin teri ng ofMMC and CMC, and (x iv) Sintering and Servi ce Behav iour.
Other related topics may also be considered. All the in viteu and contributed papers shall be presented orally. It is also planned to publi sh the Proceedings of the Conference. The las t date of submitting an abstract of the paper(s) is 30th October, 1999.
For registrati on form and further details contact:
Prof Dr G S Upadhyaya Department of Materi als & Metallurgical Engineering Indian Institute of Technology Kanpur 2080 16, India Phone: 91 -5 J 2-5976241598559 Fax: 9 1-512-590 2601590007 E-mail: gsu@ iitk .ac. in
Rolex Awards for Enterprise' 2000
The Rolex Watch Company, Geneva, has invited app lications to the ninth edition of its prestigious intern ational awards programme - the 2000 Rolex Awards forEnterpnse.
The Rolex Awards for Enterpri se are open to any person of any age from any country. Projects may be submitted in the areas of sc ience and medi cine; tec hn ology and innovati on ; exp lorati on and di scovery; the envi ronment ; or cultural.heritage.
Five winners, whose projects are j dged the most outstanding by an intern ational selecti on pane l, will each receive US $ 75 ,000, and a gold Rolex ch ronometer. Add itional awards of US $ 25 ,000 each and a steel and gold Rolex chronometer wi ll be granted to runners-up for peojects deemed particularly promising.
Applicati ons are accepted by geographic region. The deadline for entries from Asia and the Paci fi c is Oc tober 3 1, 1999 . Almost 1,000 entries have already arri ved from Europe, the Middle East and Afri ca. In 1998, a total of 2,600 applications were received from a record 130 countri es .
For furth er informati on, visit th e Rolex Awards website at
http://www.rolexawards.com. or contact : Rolex Awards Secretariat Montres Rolex S A Rue Francoi s - Dussand 7 12 11 Geneva 24 Switzerland Tel: (4122) 308 22 00 Fax: (4122) 308 25 85