RESEARCH in Jülich

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KEY TECHNOLOGIES

:: COMPUTERS SEEK A SUCCESSOR :: GLOWINGLY PRODUCTIVE BACTERIA

:: USING NEUTRONS TO CREATE NEW MATERIALS

RESEARCH

in Jülich

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RESEARCH in Jülich

The Magazine from Forschungszentrum Jülich

Cabinets containing the JUGENE supercomputer in the Jülich Supercomputing Centre. Simulations on supercomputers provide us with insights and information that would otherwise remain hidden for physical, technical, financial and ethical reasons.

Cover illustration: Instruments granting us access to the tiniest parts of the world are the key to new materials and new nanoelectronic components. In Jülich, researchers can avail of tools such as the Titan 80-300 transmission electron microscope.

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Prof. Dr. Achim Bachem Chairman of the Board of Directors of Forschungszentrum Jülich

Prof. Dr. Sebastian M. Schmidt Member of the

Board of Directors of Forschungszentrum Jülich

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umankind faces huge challenges today. How can we slow down climate change – and learn to live with the consequences? How can we stay healthy and mentally fit as we get old- er? And how can we help to feed a growing world population? We believe that research on key technologies is one way of providing targeted solutions to these problems. And it is also worthwhile from another point of view. “Key technologies are the drivers of innovation and the basis for new products, processes and services,” according to the Federal Government’s High-Tech Strategy 2020 for Germany.

Our scientists work in an interdisciplinary manner pursuing completely new approaches. This issue of Research in Jülich contains many fascinating examples of this. For instance, Jülich researchers are developing components and computational processes for the world’s best supercomputers. And they are using these supercomputers to predict air pollution over the next few days as well as the size of the hole in the ozone layer over the next ten years. Read about the key technologies researchers at Jülich are currently working on – in areas such as green IT with the objective of decreasing the need for energy in information technology or of optimiz- ing new biotechnological processes. Some scientists use neutrons as a tool to investigate “self-healing” and durable materials that will help us to conserve both energy and raw materials. Other researchers at Jülich are improving imaging techniques. This will help us to diagnose neurologi- cal diseases more accurately, which are becoming more and more common due to demographic developments.

These examples illustrate that key technologies today tend to emerge at the interfaces between the classic scientific disciplines. The Jülich campus unites different types of expertise – particularly in physics, materials science, the nanosciences, information technology and medicine. In addition, we are involved in European and international cooperations – often as lead partners – especially when a complex research infrastructure and the operation of large instruments are required. We pursue basic research with the same level of dedication as the transfer of know-how to industry and society. All of this makes Forschungszentrum Jülich the perfect place for research on key technologies. This opinion is also held by high-ranking representatives of industry and politics, as demonstrated by the inter- views in this magazine.

We hope that this issue makes for interesting reading!

The Key to our Future

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:: USING NEUTRONS TO CREATE NEW MATERIALS

Materials that can automatically seal scratches and cracks similar to the way that living organisms can heal cuts and fractures are coveted commodities for aircraft and cars. Neutron scatter- ing experiments help us to understand the self-healing mecha- nisms on the molecular level.

:: GLOWINGLY PRODUCTIVE BACTERIA

By adding a genetic extra, bacteria that are particularly productive glow, making them stand out from the rest. This will simplify the search for new bacterial strains suitable for use in industrial production.

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11 :: COMPUTERS SEEK A SUCCESSOR

Jülich researchers simulate the human brain using supercomputers. The knowledge they gain will be used to help build computers that are highly energy efficient as well as intelligent robots.

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3 Editorial

:: SNAPSHOTS

6 Research at a Glance

A kaleidoscope of pictures illustrating the latest highlights from research in Jülich on key technologies – from a warning system combating crowd congestion to a new method of looking inside complex molecules.

:: KEY TECHNOLOGIES

8 The Atmosphere in Supercomputers

Jülich atmospheric researchers use supercomputers to forecast regional air pollution. And they use simulations to predict how the hole in the ozone layer will develop in the northern hemisphere.

11 Computers Seek a Successor

13 “Germany is Abreast of its Competitors”

Interview with Prof. Henning Kagermann, President of the German National Academy of Science and Engineering acatech.

14 Glowingly Productive Bacteria

18 “Important: Technologies for Sustainability”

Interview with Prof. Wolfgang Plischke, Member of the Bayer AG Board of Management.

19 Looking at the Quantum World

Electron microscopy allows us to see tiny changes no bigger than a few billionths of a millimetre in the lengths of atoms. Such displacements are important for new data storage systems.

21 “We Need a Culture that Fosters Innovation”

Interview with Dr. Joseph Pankert, General Manager Laser Ventures at Philips.

22 Technology Through Time

Key technologies yesterday and today – in pictures.

24 Gaining Knowledge Through Precision

Nuclear physicists at Jülich are trying to solve one of the biggest mysteries of the universe and are refining particle detectors in the process.

27 “There’s no Need to Follow Every Fleeting Fashion”

Interview with Prof. Wolfgang Lück from the Hausdorff Research Institute for Mathematics in Bonn.

28 Tracking Down the Structures of Dementia

Alzheimer’s disease is the focus of the successful research being pursued by a team of structural biologists at Jülich.

30 New Insights into the Brain

Advanced tomographic techniques allow structures and metabolic processes in the brain to be imaged in more detail than was possible in the past.

33 “Opening Windows into the Future”

Interview with former Parliamentary State Secretary Uwe Thomas.

34 Using Neutrons to Create New Materials 38 Outlook for Key Technologies

On green IT, a sustainable bioeconomy and plans for the world’s most powerful neutron source.

39 Publication Details

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Magnetic Spirals

Physicists from Forschungszentrum Jülich and the universities in Hamburg and Kiel discovered a regular lattice of “magnetic skyrmions” on a surface. These are spiral and exceptionally stable spin structures, which could provide the basis for a new generation of smaller and more efficient data storage systems.

The researchers discovered the magnetic spirals, each comprising just fifteen atoms, in a one-atomic layer of iron on iridi- um.

Rolls-Royce Performs Tests at Jülich

Scientists at Forschungszentrum Jülich have developed and constructed a special test stand for Rolls-Royce, one of the world’s leading aircraft engine manufacturers. On the stand, the gas turbine components of an engine can be heated and reheated to temperatures above 1400 °C and cooled down to less than 100 °C within two minutes. This allows the lifetime of the components and their ceramic protective coatings to be tested.

Scientists at Jülich are developing and refining key technologies and using them for selected purposes. The latest findings benefit science, industry and society.

Research at a Glance

LINK TIP www.fz-juelich.de

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World Record for Simulation

The fast multipole method is an algorithm that calculates the gravity and other long-range forces acting between particles.

Scientists at Jülich have refined the method, thus speeding up relevant computer simulations significantly. During a test with the JUGENE supercomputer, researchers calculated a system comprising 3,011,561,968,121 particles in just over eleven minutes – a world record!

Tunnelling into Molecules

Physicists at Jülich have developed a simple technique to image the arrangement of atoms inside complex molecules using conventional scanning tunnelling microscopes. They have thus con- siderably expanded the capabilities of these instruments, which already play a key role in nanotechnology and materials science. The new technique uses single atoms between the tip of the microscope and the sample as a type of contrast medium.

Even intermolecular forces can be imaged in this way.

Warning System Combats Congestion

At a national league football match in the Düsseldorf Esprit Arena in September 2011, simulation scientists from the Jülich Supercomputing Centre and several Hermes project partners showcased their new evacuation assistant. The computer-aided system determines how the crowd is distributed at large events and predicts whether congestion could become critical before it actually does. In the case of fire or another critical situation, it will help the emergency services to prevent dan- gerous crushes.

Forces in Blood

Red blood cells attract each other, but the forces at work in doing so are tiny. Physicists from Forschungszentrum Jülich and two American research institutions calculated that they are around ten million times smaller than the force created by the weight of a mosquito that has landed. Computer simulations show that these mini forces nev- ertheless determine the flow resistance of blood.

Predicting the Success of Operations

Doctors refer to a narrowing of the bony spinal canal as spinal stenosis: a condition usually resulting from degeneration. In a study with twenty patients, researchers from Jülich and Düsseldorf have shown that it is possible to predict whether an operation will improve clinical symptoms of spinal stenosis, such as loss of feeling and paralysis, by means of a metabolic examination of the spinal cord using positron emission tomog- raphy (PET).

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ife without weather forecasts calculated by the weather service’s computers – for most people today, this is inconceivable. After all, what’s the point in planning a BBQ if it ends up being ruined by rain? Or of staffing the beer garden if none of these employees are needed? What would happen if there was no electricity because the wind turbines suddenly stopped turning? Scientists like Jülich researcher Dr. Hendrik Elbern are also interested in other atmospheric processes that don’t usually appear in news- paper articles or in weather forecasts on television. At the Institute of Energy and

The Atmosphere

in Supercomputers

Supercomputers serve scientists in a number of different ways – as virtual micro- scopes, laboratories and telescopes, to name but a few examples. Some researchers even use them as time machines, travelling back into the past and more importantly into the future of the Earth’s atmosphere.

Climate Research, Elbern uses computer simulations to predict what the air will contain over the next few days – how much ozone, the amount of nitrogen and sulphur oxides and how much particulate matter.

In order to compile these “chemical forecasts”, the atmospheric researcher

The predicted nitrogen oxide concentra- tion for 9 June 2011. Blue stands for a low concentration, green and yellow for a medium concentration and red for a high concentration.

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new opportunities afforded by computer simulations. They allow us, for example, to understand why measures for combating air pollution, such as car-free zones, have more of an impact on certain days than on others.

As is the case for conventional weather forecasts, chemical forecasts are only useful if they are reliable. “In order to increase the accuracy of our forecasts and possible divergences, we want to use ensemble simulations in the future.

Such simulations don’t just calculate a forecast once but rather hundreds of times,” says Elbern. The researchers simply change the starting conditions slightly or implement different computer models. Although EURAD-IM is a unique project in Germany, similar models have already been developed by other research groups, and their predictions don’t always agree.

A CODE WITH TEN MILLION LINES

“For such ensemble calculations, we need the computing capacity of ex-

tremely powerful supercomputers like JUGENE,” says Elbern. Scientists at the Jülich Climate Sciences Simulation Labo- ratory (SimLab) help him get his ensemble simulations up and running on JU- GENE, which boasts 72,000 processors and a computing power equivalent to that of 25,000 PCs. “It is definitely a challenge to make climate models suitable for use on the Jülich supercomputers using a programme code of typically ten million lines,” says Dr. Lars Hoffmann, head of the Climate Sciences SimLab.

The Jülich Supercomputing Centre (JSC) is also home to other SimLabs for other fields such as plasma physics and biology. The scientists working there com- bine their expertise in massively parallel computing on supercomputers with the respective research discipline.

Jülich stratosphere researcher Dr.

Rolf Müller from the Institute of Energy and Climate Research also works closely with his colleagues at JSC. Müller and his team mainly use JuRoPA – a computer jointly developed by engineers at JSC, collaborates with scientists from the

Rhenish Institute for Environmental Research at the University of Cologne. To- gether, they are working on the development and application of a model known as EURAD-IM. “We use this model to predict the air quality over Europe and over individual regions, such as the Ruhr area, on a daily basis. Anybody who wishes can access the results on the Internet,”

says Elbern. The data published at http://

macc-raq.gmes-atmosphere.eu/som_en- semble.php are important for people suffering from asthma or allergies, for example, as well as for amateur athletes.

The computer model can also be used for other purposes. The eruption of the Icelandic volcano Eyjafjallajökull in 2010 grounded air traffic in most of Europe. At that time, atmospheric researchers from Jülich and Cologne simulated how the cloud of ash would spread.

“Measurements later showed that the predictions were essentially accurate,”

says Elbern. Environmental agencies and other public authorities also value the

Three images of the hole in the ozone layer in the northern hemisphere on 28 March 2011. Left: Ozone concentration measured by the AURA satellites. Middle: Corresponding calculation by the CLaMS computer model. Right: Another image of this simulation highlighting ozone loss.

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the French hardware manufacturer Bull and the Munich software company ParTec. Researchers working with Müller use JuRoPA to simulate the processes behind the hole in the ozone layer above the Arctic. “Using our CLaMS computer model, we can describe the relation- ships in the polar vortex in great detail – and we can take very high-altitude clouds into account. These clouds play an important role in ozone depletion,”

explains Müller.

PREDICTING OZONE DEPLETION In order to compare predictions with reality, the scientists use data such as those from the RECONCILE project. Dr.

Marc von Hobe from Forschungszen- trum Jülich coordinated this international measurement campaign above the Arctic in spring 2010. On these flights, researchers recorded ozone depletion in the northern hemisphere during a record cold winter with particularly marked cloud formation in the atmosphere above an altitude of eight kilome- tres. Around a year later, in spring 2011, the biggest hole ever observed in the ozone layer in the northern hemisphere emerged. “We need to understand these extreme situations as best we can and simulate them so that we can then calculate the future development of the

ozone layer in a realistic and reliable manner,” says Müller. The well-known paradox of time travel also applies here:

if we implement measures today on the basis of our computer-aided insights into

Dr. Rolf Müller (left) and Dr. Hendrik Elbern (middle) from the Institute of Energy and Climate Research with Dr. Lars Hoffmann (right), head of the Climate Sciences SimLab at the Jülich Supercomputing Centre.

the future, then what was predicted to happen in the future may never actually become a reality.

Frank Frick

Together with theory and experiment, computer simulations form the third pillar of research. They provide us with insights and information that would otherwise remain hidden for physical, technical, financial and ethical reasons. The Jülich Supercomputing Centre operates supercomputers of the highest performance class for areas such as the following:

• Dispersion of pollutants

• Designing nanomaterials and quantum computers

• Galaxies and the formation of stars

• Properties of metals, semiconductors, glasses and molecules

• Strong interaction between elementary particles

• Behaviour of polymers, proteins and biological membranes

• Laser and plasma physics

• Aviation and automotive engineering

• Pedestrian dynamics

Research on Jülich supercomputers

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The brain as a paradigm. The human brain provides important information for designing future computers. This image was generated as part of a cooperation between the Institute of Neuroscience and Medicine (INM-1), with its director Prof. Katrin Amunts, and Prof. Torsten Kuhlen from the Virtual Reality Group at RWTH Aachen University within the scope of the Jülich Aachen Research Alliance (JARA).

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fter the Deep Blue computer spectacularly outwitted the then reigning chess world champion Garry Kasparov in 1997 watched by jour- nalists and the public around the world, many people considered electronic brains to be more powerful than the human super brain. It may therefore come as a surprise that there are scientists who actually use the human brain as a paradigm for the next generation of computers. One of them is Prof. Markus Diesmann. The director at the Jülich In- stitute of Neuroscience and Medicine explains, “State-of-the-art computers today are well suited for tasks that can be mastered with sheer computing power. But when it comes to using as little energy as possible to solve a problem, or indeed perception or the ability to learn, then the human brain is simply unrivalled.”

SPIRAL OF KNOWLEDGE

Diesmann’s team simulates the human brain using today’s supercomputers. The scientists hope to set a spiral of knowledge in motion. Using computer simulations, they increase their under- standing of the principles behind how the brain works. They can then use these principles to design more powerful computers and more intelligent robots.

Such simulations begin with numerous mathematical equations. They describe how a nerve cell – neuron in the jargon – actually works. The key factor in signal transduction is how the electrical activity caused by excitation of the neuron spreads. “To simulate this process in

detail, you need many different coupled equations for each and every neuron,”

says Diesmann. But in certain instances, this can be done more simply. The physicist and brain researcher continues, “If we take a single neuron to be a simple electrical circuit, then we can describe it using only two or three equations. This is often sufficient to predict whether a neuron that has been specifically excited will pass on an electrical signal or not.”

However, even with only a few equations per neuron, we still need enormous computing capacities to simulate small regions of the brain. A volume of only

Computers Seek a Successor

Supercomputers have become an indispensable tool for almost all scientific disci- plines. What is astonishing is that the simulations they perform are also helping us to investigate new technologies that could one day take over certain tasks from computers.

one cubic millimetre of our brain contains around a hundred thousand neurons – and each of these is connected to around ten thousand others. The total number of contacts is enormous! “To simulate this cubic millimetre, we must account for a billion contact points between the neurons,” says Diesmann. The simulations are made even more complicated by the fact that key variables vary strongly within this cubic millimetre of the brain. For example, such an area in the visual cortex comprises six layers, and the neurons in each of these layers are packed together with different densi- ties and are connected to many other cells.

Diesmann is involved in developing software known as NEST (www.nest-initiative.org), which is used by brain researchers throughout the world and is continuously being expanded. NEST allows scientists to mathematically describe single neurons and to enter data on anatomy and electrical properties. As a result, they get an evaluation of the brain activity. In Jülich, Diesmann and his team work with the experts at the Jülich Supercomputing Centre (JSC) who provide extensive support, ensuring that such simulations can be productively im- plemented on supercomputers of the highest performance class. The results are integrated into the European Brain- ScaleS project, which uses neural net- works as a model to develop new types of microchips known as neuromorphic hardware. Diesmann and his researchers have already achieved a breakthrough.

In a simulation, they reconstructed the

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behaviour in a region of the visual cortex measuring one cubic millimetre – and they did so in such detail that the calculated activities agreed with the experimental findings.

TOWARDS THE QUANTUM COMPUTER Brain researchers are not alone in using supercomputers to seek models for the next generation of even more powerful computers. Scientists at Jülich also use them to take an in-depth look at new emerging information technologies.

Quantum computers could achieve an

However, Prof. Kristel Michielsen from the Jülich Supercomputing Centre has successfully simulated a much larger system on the JUGENE supercomputer.

She calculated a (highly idealized) quantum computer system with 42 qubits, which is a world record. This was made possible by simulation software, which was developed for this purpose and tai- lored to Germany’s fastest computer JU- GENE. It ensures that hundreds of thousands of processors work together seamlessly on the calculation. “We are now using this software to investigate other quantum-mechanical systems, for example, to identify whether fundamental problems occur and the options open to us to correct them,” says Michielsen.

By working in this manner, Jülich researchers have already unearthed many insights that will prove useful to all de- velopers of real quantum computers.

Frank Frick inconceivable tempo when processing

certain tasks. For example, in contrast to conventional processors, they would be able to perform multiple operations simultaneously in one switching process.

The reason behind this is linked to the information unit used. A classical bit either has a value of 0 or 1. A quantum bit (known as a qubit for short), on the other hand, can be a superposition of different values.

Up to now, only initial prototypes of quantum computers with a capacity of a few qubits have existed in laboratories.

the recycled water can be simply released into the air. This does away with the need for technical and energetic efforts to cool the water down to 16 °C.

The Jülich Supercomputing Centre (JSC) is hoping to test the technique thorough- It sounds like a paradox: warm water

with a temperature of around 40 °C is more efficient at cooling supercomputers than cold water with a temperature around 16 °C. And yet this strategy is promising. The reason is that the heat of

Energy-efficient cooling for supercomputers

ly on a cluster computer. If it is proven worthwhile, then it will be used to cool future generations of supercomputers at JSC.

Prof. Markus Diesmann is convinced that simulations of the human brain will help us to construct powerful and energy-efficient computers in the future.

Prof. Kristel Michielsen in front of the Jülich supercomputer JUGENE, which she uses to simulate a potential information technology of tomorrow – the quantum computer.

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Question: How would you define the term “key technologies”?

Kagermann: I understand it to mean technologies that have a large impact on the fields of action of mobility, energy, health, communications and safety.

These are areas that have been prescribed by society. Key technologies are beneficial to several of these fields and have a great deal of leverage.

Question: You referred to socially prescribed fields of action. Are you basing this idea on the High-Tech Strategy where the German Federal Govern- ment set down important topics for the future with the objective of en- hancing Germany’s innovative strength?

Kagermann: Partially, yes. But these fields of action exist worldwide. At acatech, we looked at other countries and found that these areas apply across the board. However, this is not really surprising because all countries are driven by the same global influences: a growing world population, dwindling resources, climate change and demographic developments.

Question: What should be done to pro- mote the development of key technologies in Germany?

Kagermann: I think we’re already doing quite a lot. We are on a par with our competitors both on a European and an international level. One of the reasons for this is the Federal Government’s High-Tech Strategy for Germany. How- ever, we do still have some weak points – for example, the necessary skilled workforce, the lack of which will become

an even more painful problem in the future, and the financing of innovation.

Question: The general opinion in Jülich is that new key technologies tend to emerge at the interfaces between the classic scientific disciplines. What do you think?

Kagermann: I fully agree with this. To- day, there is even talk of the conver- gence of technologies, that biotechnology, nanotechnology and information technology and possibly even brain research will merge to a much greater extent. Information and communication technologies will also increasingly influ- ence the classic technology areas, such as factories of the future or intelligent power grids in the era of the transforma- tion of the energy sector.

Question: Do we need basic research to develop key technologies?

Kagermann: Yes. Sound basic research is essential. However, we also need to

work on transforming our investments in basic research into marketable products and services. After all, we in Germany don’t want to research solely for the benefit of those abroad. This is why we should also pursue applied research and keep our eye on the innovation chain as a whole.

Question: How do you know if a technology has the potential to become a key technology?

Kagermann: On the one hand, there are processes and instruments we can use to systematically analyse technologies and assess their future significance. On the other hand, it’s like shares on the stock market: if you knew for sure how things will develop in the future, then you’d be rich. Instead, there is always a risk of backing the wrong horse.

Interviewed by Frank Frick

Interview with Prof. Henning Kagermann

“Germany is Abreast of its Competitors”

Physicist Prof. Henning Kargermann is President of the German National Acade- my of Science and Engineering acatech.

The National Academy represents the in- terests of the German scientific and tech- nological communities at home and abroad. It supports and advises policy- makers and society on issues related to the future of technology. Prior to his posi- tion at acatech, Kagermann was Co-CEO of SAP AG for a number of years.

Henning Kargermann

The president of the German National Academy of Science and Engineering is con-

vinced that a lot is being done here in Germany to advance key technologies.

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Glowingly

Productive Bacteria

An increasing number of active ingredients in medicine, food products and recyclable materials are being produced using enzymes and microbial cells. The biotechnology sector today boasts a global turnover of around € 50 billion. Researchers at Jülich are working on boosting this booming industry even more. Their latest coup: they can make single – particularly interesting – bacterial cells glow so that they can be distin- guished from the mass of thousands of others.

They have developed a particularly efficient method of fishing out high-yield bacteria from the cultures grown:

Dr. Lothar Eggeling and Dr. Julia Frunzke.

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hirty minutes is all it takes biotechnologist Stephan Binder, who is working on his PhD at the Jülich Institute of Bio- and Geosciences, to separate specific bacteria that produce particularly high yields of lysine (an essential amino acid) from a motley crew of around eighteen million bacteria.

This process, known as screening in the jargon, usually takes several weeks.

“Conventional screenings involve serious amounts of material,” says Binder’s colleague Dr. Julia Frunzke. “Bacterial cultures are prepared and incubated on hundreds of Petri dishes and we don’t even know which of these cultures produces lysine.” From the eighteen million Corynebacterium glutamicum bacterial cells, typically only as few as a hundred remain particularly productive. These cells are then cultivated further in order

analyse their genetic makeup and their biochemical capabilities in detail. The new method effectively presorts the bacteria – it sorts the wheat from the chaff, so to speak.

BACTERIA IN THE SERVICE OF INDUSTRY

Originally found in soil, genetically modified Corynebacteria have been used in industry for years to produce additives such as the amino acid lysine.

Lysine is used, for example, in infusions for the seriously ill and as a fodder sup- plement. It eases the digestion of grain and course-ground cereal in cows. Jülich biotechnologist Dr. Lothar Eggeling is one of the top international Coryne spe- cialists. He believes that the annual global requirement of around one million tonnes and a turnover of two billion US

dollars every year make improvements in lysine production worthwhile. “If we can find a bacterial strain that is only one or two percent more effective, this will lead to an additional turnover of between twenty and forty million dollars. And finding a new strain is not just profitable, it also conserves resources.”

Scientists at Jülich are using Corynebacterium glutamicum as a model organism for their new screening method. The cell itself, in contrast, has a highly sensitive and specific control system for lysine and several other metabolic products. A special “watchdog”

protein recognizes when there is too much lysine in the cell and immediately provides relief. It starts a genetic program that increases the export of lysine out of the cell. Several of these Dr. Katharina Nöh analyses the complex metabolic pathways in genetically modified bacteria. She uses computer simulations to image the metabolic fluxes.

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specialized “watchdog” proteins – known as transcription regulators in the jargon – protect the cell from an excess of metabolic products by ensuring that these products are selectively expelled from the cell.

“Our method exploits nature’s tool- box,” says Julia Frunzke. The researchers smuggle an additional circular piece of the genome into the bacterial cell. It comprises two parts. The first part is the recognition region for the “watchdog”

protein. The second part does not com- prise the original program to export the lysine, but rather the command to produce a natural fluorescent colour. “What we then have is a highly specific biosensor that does not affect the metabolism of the cell in any way. The normal genetic makeup, in other words the watchdog and export functions, remains unaffect- ed by this intervention,” explains Lothar Eggeling.

PATENT SECURED

After the researchers have added the genetic extra to the cell, they use UV radiation to ensure that as many genetically different mutants as possible are created. Bacteria that produce large quantities of lysine glow more than those that produce small quantities.

Eggeling and his team have used this method successfully to find very promising new bacterial strains, which they went on to patent.

The basic principle behind the method has also long since been patented.

This new screening method can be used to construct a biosensor for every known

“watchdog” protein of any bacterium.

Escherichia coli, which is a bacterium commonly used in industry, is also very promising. “In addition to numerous amino acids such as lysine, valine and me- thionine, we could also use it to track down pharmaceutically interesting mol-

ecules – for example, taxanes, which are used in malaria medication and cancer drugs,” says Eggeling, who successfully tested the Jülich technique on this type of intestinal bacteria.

Industry is also interested for another reason. “The new method is attractive because the sensor can be used during normal operation to quickly ascertain exactly how many of the highly productive bacteria contained in the huge industrial fermenters actually produce the desired product – and how many just sit back and do nothing instead!” says Frunzke.

DIVERSION FOR GLOWING CELLS PhD student Stephan Binder is de- lighted that he doesn’t have to sort out the glowing cells by hand using a microscope and pipette. A commercial flow cytometer does this job for him with im- mense speed and precision. It is usually used to analyse blood. The cells contained in a solution are extracted using a capillary tube before being individually passed under a laser beam. Up to 30,000 cells per second are run past the light source. The instrument recognizes the glowing cells and reroutes them to a Petri dish. The Petri dish moves a few centimetres after each “hit”, allowing each individual cell to create its own colony of offspring as even more cell material is required for the subsequent analyses.

Bacterial strains are grown in Petri dishes like this.

Bacteria under the fluorescence micro- scope. Thanks to a genetic extra, their luminosity shows how productive they are.

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Prof. Marco Oldiges and his team at the Jülich Institute of Bio- and Geo- sciences test how productive a promising new bacterial strain actually is. The strains are placed in a bioreactor for analysis. “They have much better living conditions there than in a Petri dish or in a small shake flask,” says Oldiges. Such realistic industrial conditions also guar- antee greater control: the researchers at Jülich can control exactly how much glucose – i.e. sugar – is added to the process and how much lysine is produced as a result. “Our ultimate aim is to con- vert 100 % of the glucose to achieve a maximum lysine yield – but we have yet to see this ideal case become a reality,”

says Oldiges grinning. In order to understand exactly how the sugar is metabo- lized, the researchers label selected carbon atoms in the glucose molecules with a minimally heavier carbon isotope, which only accounts for 1 % of carbon in the natural world. Following a precise time protocol, they remove samples from the bioreactor and investigate when and how frequently their labelled carbon appears in certain metabolic products.

MULTIPLE BRANCHES

Before lysine is formed, sugar is con- verted into a number of intermediate products – known as metabolites in the jargon – and this process is never linear.

The metabolism of a living organism comprises multiple branches: many substances are not just involved in one reaction but in several. And certain reac- tions do not just create the main products but also other substances. These by-products can negatively affect lysine production and reduce the yield. To use a metaphor, the researchers are dealing with a network of racetracks, one-way streets, roundabouts, slow lanes, building sites and cul-de-sacs. Depending on where they start, the regulations and the route, the various road users respond to each other, helping each other to accelerate but also blocking each other and causing traffic jams.

“The whole process doesn’t just take place on one level, as is the case for road traffic. Instead multiple levels are involved and each level influences the other. Unfortunately, we only understand bits and pieces of the highway traffic

code for bacteria,” says Marco Oldiges.

In order to keep track of the bigger picture, the researchers transfer their results to sophisticated computer models.

“Using these models, we can understand where the metabolism experiences bot- tlenecks and whether there is a lack of nutrients, for example,” says mathematician Dr. Katharina Nöh, specialist in metabolic flux analysis. The advantage is that time-consuming and expensive laboratory experiments are no longer necessary. Instead, each metabolic screw can be virtually tweaked and the consequences calculated.

Whether the calculations are correct or not will be revealed by the living object at the latest. By switching selected genes on and off, Oldiges and Nöh can accelerate or inhibit the calculated metabolic pathways. Recently, they celebrat- ed an important success using this method: they excited Corynebacterium glutamicum to produce more of the amino acid valine, which is an elementary structural element in antiviral medica- tions for herpes and HIV.

Brigitte Stahl-Busse

Prof. Marco Oldiges investigates promising bacterial strains under conditions similar to those in industry.

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Question: What should be done to pro- mote the development of key technologies in Germany?

Plischke: We need to be more open to innovation! For example, I am concerned that large sections of the German population continue to reject green biotechnology. Without new seed varieties that ensure increased yields based on state- of-the-art biotechnological methods, we won’t be able to feed the growing world population in the future and we won’t be able to create a solid basis for renewa- ble resources. The new Bioeconomy Sci- ence Center, in particular, in which Forschungszentrum Jülich plays a key role, aims to address such grand challenges facing society – it wants to find solutions to problems such as feeding the world’s population, the raw materials

and energy issue, and the consequences of climate change.

Question: How important is it for a company like Bayer that research on key technologies receives public funding?

Plischke: For Bayer, different types of research funding are important: in addition to support in terms of technology acceptance by policy makers and society, we also believe that funding is vital for projects dealing with certain topics and application-oriented projects. Con- sortia comprising universities, state- owned research institutions, small and medium-sized enterprises and industry are particularly efficient when it comes to laying the groundwork for the wide- spread application of key technologies.

In addition, general tax concessions for research could provide added impetus for Germany’s innovative competitive- ness: the revenues waived by the tax authorities would be well invested. They would be demonstrably used for additional research, to consolidate innovation and growth – and would ultimately create new jobs and increase tax revenues.

Interviewed by Frank Frick Question: What technologies do you

immediately think of when you hear the words “key technologies”? Please list a maximum of three.

Plischke: The first things that come to mind are biotechnology and nanotechnology. After these, general technologies that foster sustainability are particularly important. For example, new process technologies that allow us to use energy and resources more efficiently.

Question: How would you define the term “key technologies”?

Plischke: For us at Bayer, key technologies are technologies that we can use to pursue our mission “Science For A Bet- ter Life”. In other words, technologies for innovative products that benefit all of us – whether it be in the area of health, nu- trition or high-quality materials. We want to contribute to the sustainable development of society with our innovations.

Prof. Dr. Wolfgang Plischke has been a member of the Board of Management of Bayer AG since 1 March 2006. At the in- ternational concern, the biologist is re- sponsible for Innovation, Technology and Environment, as well as for the Asia-Pacif- ic region.

Wolfgang Plischke

Interview with Prof. Dr. Wolfgang Plischke

“Important: Technologies for Sustainability”

The member of the Bayer Board of Management outlines his view of key technolo-

gies and calls on the Germans to be more open to innovation.

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M

aterials research as it stands today has begun to exploit the atomic world over the past decade. The platform for doing just this is provided by electron microscopes with aberration-corrected optics. However, even the very best optics is no good in the world of atoms if used alone. This is where quantum physics reigns and the notion of an image here defies that of our everyday experience.

This has quite unexpected consequences. For example, the image of a structure depends on the thickness of the speci-

men. In the image, “atoms” can appear in places where there are none in reality – or vice versa. You have to know exactly how thick the specimen is. But there is no such thing as a yard- stick for the atomic level. And to make matters even more complicated, atoms tend to be transparent for electrons. Their contrast is extremely weak, and compared to an optical microscope or a camera, it gets even worse the closer the adjust- ment of the objective lens is to exact focus. In order to see anything at all, you have to work out of focus – in other words,

Looking at the Quantum World

The atomic world is hidden from view; its dimensions are unimaginably small. And yet

the tiniest of details regarding the position and movement of atoms are what deter-

mine the properties of materials. Jülich pioneers in electron microscopy Chunlin Jia

and Knut Urban (pictured above) have developed a technique that can be used to

identify tiny picometre-sized displacements of the atoms and to measure these with

unrivalled precision. Such changes as tiny as a billionth of a millimetre in the position

of an atom, for example, are important for novel ferroelectric digital data storage.

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the objective lens is usually “defocused”. The result then depends sensitively on the chosen focus value, but this is not directly accessible in atomic dimensions. On top of this, a tilted specimen produces a distorted image. How distorted the image is depends on the type of atom being imaged. When different types of atoms occur together, very complex conditions exist. In order to be able to use the images at all, the specimen has, in principle, to be adjusted to within a few hundredths of a degree, but there is no instrument that could be used to tech- nically realize this in an atomic range.

Chunlin Jia and Knut Urban work at the Peter Grünberg In- stitute at Forschungszentrum Jülich and at the Ernst Ruska- Centre. Since they first used an aberration-corrected electron microscope for their work ten years ago, nobody has been able to make more accurate measurements. “The laws of quantum physics defy our intuition. But what astonishes us and even appears absurd is what provides information and allows us to measure with an unimaginable precision when we use computers to analyse the images because they “understand” the laws of quantum physics,” says Urban.

DEDUCING INFORMATION “BACKWARDS”

When an electron wave is sent through an object in an electron microscope, then this wave is modified. This object-specific modification does not just provide us with information on the object but also on the imaging conditions. In order to de- duce information “backwards” from the images, a computer is used to construct an atomic model – based initially on intuition alone. Comparing this model with the real images then provides us with clues for improving it. The calculation is repeated using the progressively modified model until the calculation and observation agree. This process should not be underesti- mated. Not only do the large number of atoms have to be coordinated but the values of the optical parameters, the thickness

and the orientation of the specimen also have to be varied in such a way that a consistent data set is created.

That such a feat is possible was for example shown by Jia and Urban working together with colleagues from the Max Planck Institute of Microstructure Physics in a paper published by the well-known journal Science. They succeeded in detect- ing what are known as flux-closure domains in ferroelectrics for the first time and also showed that ferroelectric dipoles in such materials continuously rotate on an atomic scale. Al- though the existence of such closure domains had been predicted theoretically for almost a decade, it had never been proven experimentally. Their quasi-continuous rotation is necessary for the realization of nonvolatile ferroelectric memory devices.

MEASUREMENTS ACCURATE TO THE PICOMETRE

Ferroelectrics are oxide materials containing crystalline unit cells in which the atoms are arranged in such a way that their electric charge centres do not coincide geometrically. In the compound lead zirconate titanate (PbZr_0.2Ti_0.8O₃) used by Jia, Urban and their colleagues, the negative charge of the oxygen atoms and the positive charge of the metal atoms forms a per- manent electric dipole. The Jülich researchers took measurements accurate to the picometre of the strength and direction of these dipoles. The surprising finding: despite being much more rigid than magnetic dipoles, the electric dipoles can be rotated in the smallest of space. This facilitates the formation of triangular domains no bigger than a few unit cells. Researchers had overlooked these in the past because they were so unbe- lievably small.

Their discovery was simultaneously exciting news for researchers working on ferroelectric vortex memory devices.

Four of these domains together form an elementary vortex no bigger than a nanometre in which the electric field rotates 360 degrees. Based on this direction of rotation, clockwise or coun- ter-clockwise, a digital bit can be realized in the tiniest space.

The editorial team would like to thank Prof. Knut Urban for his article.

Physicist Prof. Knut Urban was head of the Jülich Institute of Micro- structure Research – today part of the Peter Grünberg Institute – and held a chair for experimental physics at RWTH Aachen Univer- sity from 1987 to 2011. He was also president of the German Phys- ical Society (DPG) from 2004 to 2006. Urban has received many prizes and awards, including the Wolf Prize, which is one of the most prestigious awards for physicists. He is also the first JARA Senior Professor.

Materials researcher Prof. Chunlin Jia was selected for China’s 1000 talents programme and was appointed professor at Jiaotong University in Xi’an. The initiative aims to attract top researchers working abroad back to China in an effort to expand and support the booming research sector. Jia divides his time equally between Jülich and Xi’an. Jiaotong University has just finished a new build- ing for his institute.

Knut Urban

Chunlin Jia

Electron micro- graph of the ferroelectric material lead zirconate titanate (PbZr_0.2Ti_0.8O₃).

The arrows indi- cate the direction of the electric dipoles.

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Question: What technologies do you immediately think of when you hear the words “key technologies”? Please list a maximum of three.

Pankert: I immediately think of the optical technologies because I work with them on a professional level. Semicon- ductor technology also comes to mind because it’s enormously important for almost all sectors in industry and for our society, as does genetic engineering.

Question: Can a key technology simply be defined as a technology that deci- sively shapes or will shape our lives?

Pankert: In principle, yes; but the technology itself isn’t always visible. For example, the lives of the younger generation are characterized by Facebook.

However, this doesn’t make social net- working services a key technology. They only exist because of the progress made in communications and information technology. Only at this level, can we speak of a key technology.

Question: To what extent do key technologies contribute to the solution of issues facing society?

Pankert: I’d approach that question the other way around. When a technology doesn’t help us to solve social problems, then it’s not a key technology but rather a niche technology. For example, optical technologies and their applications, such as LEDs, are closely connected to the energy supply problem.

Question: A famous quote underesti- mating the potential of a key technology is a statement allegedly made in 1943 by Thomas Watson, who at the time was chairman of IBM. He foresaw

“a world market for maybe five computers”. How can a company like Philips avoid such errors?

Pankert: There’ll always be “Watsons” – people who have achieved great things but still fail to recognize developments at an early stage. Like most companies, at Philips, we have given up trying to control the entire innovation chain. What is decisive for us is that even if we do miss a development, we have to be in a position to catch up – for example, by buying

out smaller companies and their technologies. The key word is “open innovation”: we have to keep our eyes open for everything going on around us, for example, at universities and research institutions. This also means that we need a culture that fosters innovation at universities and research institutions and indeed in society at large.

Interview with Dr. Joseph Pankert

“We Need a Culture that Fosters Innovation”

As General Manager Laser Ventures, Dr.

Joseph Pankert is responsible for three Philips’ subsidiaries, out of which he aims to develop a business line within the inter- national company comprising hundreds of employees. Previously, he played a key role in setting up a joint venture with the Fraunhofer Institute for Laser Technology.

Today, this joint venture goes by the name of XTREME technologies GmbH and was sold by Philips in 2009.

Joseph Pankert

The Philips manager talks to us about the division of roles in companies, research

institutions and universities in the development of key technologies.

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Technology

Through Time

Key technologies yesterday and today

1 In 1936, civil engineer Konrad Zuse designed a freely programmable mechanical calculator: the Z1 – the world’s first computer. The Z1 was destroyed during the Second World War. The picture shows the punched tape reader in a replica constructed for the German Technology Museum.

In the computer room at Jülich in 1967, scientists worked with computers whose performance was tiny compared to that of today’s supercomputers. Computing power today allows us, for example, to simulate the Earth’s atmosphere (see p. 8).

2 We don’t know for sure who built the first microscopes at the end of the sixteenth century. In the nineteenth century, the optical microscope be- came an important instrument in medicine and the natural sciences.

The development of the electron microscope in the early 1930s by Ernst Ruska allowed scientists to forge ahead into even smaller dimensions.

Researchers at Jülich have also been using such instruments for years, as shown by the picture taken in 1968.

Using modern microscopes in the Ernst Ruska-Centre, we can now even take a look at the quantum world (see p. 19).

3 On 8 November 1895, physicist Wilhelm Conrad Röntgen discovered a type of radiation that could pass through matter and the human body.

During his subsequent public lecture, he took a picture of anatomist Rudolf Albert von Kölliker’s hand. In 1971, medical scientists at Jülich injected a patient with harmless radioactive tracers and measured the radiation emitted using a gamma camera.

Today, scientists at Jülich use MRI scanners to produce high-resolution and high-contrast images of the human brain (see p. 30).

1 Computing

1967

2007 1936

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2 Microscopy

3 Imaging techniques

2011

2007

1968

19^th century

1896 1971

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Gaining Knowledge Through Precision

Scientists pin their hopes on particle accelerators believing, for example, that they will provide new impetus for medicine and materials research. Nuclear physicists at Jülich are developing these large-scale facilities including the necessary particle detectors and are hot on the trail of one of the greatest mysteries of the universe.

W

hy is there us, the Earth and everything else? Nuclear physicists at Jülich have made it their mission to answer this age-old question. But while others try to answer this question by philosophizing or medi- tating, the researchers are trying to wrest nature’s secrets from her using precision physics.

On their quest for information, the scientists came across a particular type of decay of the eta particle (see “The Participating Particles”, p. 26). An eta

only lives for half a quintillionth of a second. For comparison, the clock rate of computer processors used today is somewhere in the region of a billion cycles per second. One of these tiny cycles is two billion times longer than the lifetime of an eta.

DESTRUCTIVE ANTIMATTER

Our existence causes a problem for physicists. Actually, we shouldn’t really exist at all. The Big Bang should have produced equal amounts of matter and

antimatter. But, these two forms cancel each other out. Therefore, shortly after the creation of the universe, they should have destroyed each other. Yet this didn’t happen. How can the obvious excess of matter be explained? That matter and antimatter accumulated in clusters quite independently of each other is something that Prof. Siegfried Krewald from the Jülich Nuclear Physics Institute (IKP) considers unlikely, as do most of his colleagues. “The two types of matter would destroy each other as soon as

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these clusters meet. Gigantic amounts of energy would be released in the process.” And this is something that astron- omers could not overlook.

PUZZLING EXCESS

Many scientists therefore assume that the asymmetry of matter and antimatter is rooted in the laws of physics themselves. The “rules” of physics give preference to matter over antimatter according to this concept. And this is the reason why more matter remains. “This is known as CP violation, which is indeed an integral part of the Standard Model and has been demonstrated in many experiments,” says Krewald’s colleague Dr.

Christoph Hanhart. He continues, “But unfortunately it is several orders of mag- nitude too small to explain the observed excess of matter in the universe, which is millions of times greater.”

This is where the eta particle comes into play – or to be more precise, how it decays. Physicists assume that nature involves a symmetry violation that goes

beyond what is predicted in the Stand- ard Model of particle physics. This would explain not only the excess of matter in the universe but would also affect the decay of eta.

“Around one eta in every ten thousand decays into an electron, a positron and one positively and one negatively charged pion,” says Dr. Volker Hejny, who is also from IKP. These four particles repel each other (see image on p. 26). “If a symmetry violation really does exist that is not predicted by the Stand- ard Model, then we should find an asymmetry in the geometrical arrangement of the orbits – and we should find this for a maximum of two percent of these rare and special eta decays,” says Henjny.

Hanhart clarifies this, “Two percent is the absolute limit. The effect is probably much smaller.”

MILLIONS OF COLLISIONS

The combined COSY accelerator and WASA detector, which was transferred from Jülich to Uppsala in Sweden a few

years ago, was the first instrument to facilitate the extremely precise measurements required. The COSY cooler syn- chrotron spanning a length of 200 metres produces an extremely uniform proton beam that is “cooled” using different techniques. This beam hits a second proton at almost the speed of light, on average millions of times per second.

Every ten thousand collisions or so, an eta is produced. Its decay products are what the WASA detector equipped with around 6,000 detector elements search- es for like a “tracking dog”.

In order to tackle the resulting flood of data, the nuclear physicists have per- fected the read-out electronics of WASA in cooperation with their colleagues at the Jülich Central Institute for Electron- ics. “We can now record ten thousand events per second,” says Hejny. To date, the researchers have recorded several hundred million eta decays. Whether the expected CP violation is among them will be revealed when the data is analysed over the next few years.

Prof. Siegfried Krewald, Dr. Christoph Hanhart and Dr. Volker Hejny (from left to right) in the hall con- taining the Jülich particle accelerator COSY.

The WASA detec- tor used by the Jülich nuclear physicists to reg- ister the decay products of the eta particle.

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THE “PARTICIPATING” PARTICLES

Mean lifetime Mass (in grams) Electric charge

Proton

Theoretically stable in the Standard Model

1.67 * 10^-24 Positive A basic component of matter. The nucleus of a hydrogen atom comprises exactly one proton.

Antiproton

1.67 * 10^-24 Negative

The antiparticle of the proton. The antiproton was first artificially produced in 1955 in the Lawrence Berkeley National Laboratory (LBNL) in California. Researchers are currently investigating whether antiprotons could be used in radiotherapy. It is hoped that they would have less of a negative impact on healthy tissue.

Electron

0.91 * 10^-27 Negative A basic component of matter. The nucleus of a hydrogen atom is orbited by exactly one electron.

Positron

0.91 * 10^-27 Positive

The antiparticle of the electron. It can be produced, for example, by a radioactive decay of atomic nuclei. When it collides with an electron, it is annihilated.

Pion

26 billionths of a second (26 * 10^-9 seconds)

0.25 * 10^-24 Positive or negative

Pions are produced, for example, when cosmic radiation collides with gas atoms in the Earth’s atmosphere. In ad- dition to electrically charged positive and negative pions, neutral pions also exist. They have a much shorter lifetime.

Eta

0.51 quintillionths of a second (0.51

* 10^-18 seconds)

0.98 * 10^-24 Neutral

A type of meson, like the pion. It has such a short lifetime that it cannot be directly detected. However, by proving that the particles into which it decays exist, we can also prove that it existed.

The know-how gained by the Jülich scientists operating COSY is proving in- valuable for one of the largest research projects in the world: the international FAIR accelerator complex which is currently being constructed in Darmstadt.

The Jülich group are designing the FAIR accelerator HESR – COSY’s “big broth- er”. As a centre of antimatter physics, it will make experiments with antiprotons possible that will hopefully throw light on the mystery behind our existence.

Axel Tillemans

Significant decay

One in ten thousand etas (green sphere) decays into an electron (small red sphere), a positron (small blue sphere) and into one negative (large red sphere) and one positive (large blue sphere) pion. The orbits of the electrons and positrons lie in one plane, while the orbits of the two pions lie in another plane. If the angular relationship between these two planes is asymmetrical, this could explain why matter exists in our universe.

eta

electron negative pion

positron positive pion

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Question: What technologies do you immediately think of when you hear the words “key technologies”?

Lück: Physics, chemistry, biology and medicine. These four traditional scientific disciplines will merge to an even greater degree in the future. And then I would also include mathematics as a future key technology.

Question: An unusual answer that makes the next question even more important. How would you define the term “key technologies”?

Lück: As an area of science from which society can expect to benefit in the form of greater progress.

Question: But by listing the traditional scientific disciplines, medicine and mathematics, are you not labelling science as a whole a key technology?

Lück: No. I am saying that a key technology is a scientific domain in which society invests because it counts on high re- turns. These domains change over time.

Thirty years ago, physics and chemistry were top of the list. Today, we are pin- ning our hopes on the life sciences, and in the future it will probably be something different. Scientists and policy makers face the continuous challenge of identifying the areas or domains that look like they could be particularly promising for society.

Question: But how can policy makers and society succeed in identifying these domains in order to then selectively invest in the relevant research?

Lück: It has to be said that this is indeed a difficult task for policy makers. On the one hand, a continuous review process is required and research must be funded in areas where quality is obvious. On the other hand, there’s no need to follow every fleeting fashion. Take the example of BSE or mad cow disease as it is known colloquially. A lot of money was invested in research at short notice – today, you hardly hear mention of BSE any more. I have a suggestion here. Although the major part of research funding should be invested in planned research, a small

proportion should be invested in blue skies research – in other words in research where we don’t demand that scientists provide solutions to a particular problem within, for example, three years.

If we neglect such blue skies research, then we rob ourselves of long-term product development. By the way, some companies appear to have recognized this.

Microsoft, for example, has a group in California comprising only mathematicians who work on very fundamental issues.

Interview with Prof. Wolfgang Lück

“There’s no Need to Follow Every Fleeting Fashion”

Wolfgang Lück is a professor at the University of Bonn and the Hausdorff Research Institute for Mathematics. His research field, algebraic topology, belongs to what is known as pure mathematics.

He has been awarded the Max Planck Research Prize and the Gottfried Wilhelm Leibniz Prize and was president of the German mathematicians’ association in 2009 and 2010.

Wolfgang Lück

The mathematician and scientist involved in basic research tells us

what funding bodies can learn from the example of BSE. He explains

why he considers physics, chemistry, biology and medicine to be key

technologies.

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Tracking Down the

Structures of Dementia

Scientists at Jülich are trying to decipher the structure and interaction of proteins that play a role in all processes of life. Methods used in structural biology have prov- en to be an important tool. The findings obtained are being used to improve the di- agnosis and treatment of Alzheimer’s disease, which affects around a million people in Germany alone.

I

f you can’t remember the names of your own children, lose your way just outside your own house and find it difficult to dress yourself, then you could be suffering from an advanced form of Alzheimer’s dementia. Although the medication that is currently available rarely helps such patients, researchers are still working on new drugs. “Drugs based on new active ingredients would probably have a better chance of success if they were prescribed before the severe symptoms become apparent, as the disease process is too advanced in the brain at this stage,” says biologist Dr. Susanne Aileen Funke. This is the reason why a research team at Jülich, headed by Funke and biochemist Prof. Dieter Willbold,

small soluble aggregates comprising a few amyloid molecules,” says Funke.

In order to demonstrate these harmful aggregates, the Jülich team from the Institute of Complex Systems prepared microscopic probes. These comprised short amino acid chains – peptides – which bind to the ß-amyloids. These peptides contain very specific amino acids that do not occur in natural proteins.

These D-amino acids are structured like a mirror image of the natural L-amino acids. The advantage of the artificial mirror images: they are not attacked by degra- dation proteins in the body and are therefore particularly stable. As the im- mune system does not recognize them as foreign proteins, they also cause very few side effects.

The Jülich scientists working with Funke and Willbold tested a whole range of such peptides. Two of these were found to be particularly suitable. The first one is known as D1 and can be used in combination with imaging techniques to identify the harmful aggregates of ß-amyloid molecules in the brain – an important step towards new diagnostic methods. The other is called D3 and pro- tects cell cultures from the ß-amyloid compounds – thus providing a basis for preventive medication and therapeutic drugs.

The scientists at Jülich worked with researchers at the University of Alabama in the USA to uncover the properties of the D1 molecule. In human tissue sections, D1 was only able to recognize wants to track down the molecules that

paralyse the brain as early as possible.

USING MIRROR IMAGES IN THE SEARCH

At the moment, the diagnosis can only be made with certainty after the patient has passed away, when the charac- teristic deposits can be confirmed between the brain cells of the deceased (amyloid plaques). They are formed by an aggregation of several ß-amyloid molecules – chains comprising around forty amino acids (the building blocks of proteins). The insoluble deposits have long been considered the cause of the symptoms. “But today, we know that a key role is played in the disease process by

Dr. Susanne Aileen Funke and Prof. Dieter Willbold are tracking down ß-amyloids which play an important role in Alzheimer’s dementia.