Human Brain Modelling

Simulation

Disturbances Efficiency

SignalsMolecules

Structure

::Humanbrainmodelling Interdisciplinary Insights into the Human Brain

:: Recycling Valuable Materials: Hidden Treasures in Electronic Waste

:: Climate Research: Measurement Flights Around the Globe

The Magazine from Forschungszentrum Jülich 02|2013

RESEARCH in Jülich

Cloudy – at least from a professional point of view, this is good news for Jülich scientist Birger Bohn. Together with 120 researchers from 16 institutions, he is investigating the spatial struc-ture of clouds and their composition in the HD(CP)2 project. They aim to develop better models to describe and predict weather and cli-mate. More than 20 different measuring instru-ments are being used during the first part of the project (HOPE), most of them around the clock. The equipment includes swivelling radar units, numerous ground sensors, and radiosondes for airborne measurements. With these devices, as many weather situations as possible will be captured in an area measuring ten kilometres by ten kilometres around Forschungszentrum Jülich. The silvercoloured spherical cap in this photo also collects data: with the help of the camera mount-ed above, it records the degree of cloud cover.

:: IN THE PICTURE

:: NEWS IN BRIEF 4

:: COVER STORY 6

6 OperationBrain Joint work on a new understanding of the human brain

:: RESEARCH AT THE CENTRE 12

12 MicrocapsulesUnderFireWhen size determines stability

14 EffectsoftheBlackPick-Me-UpWhy crowding out keeps us awake

16 HotontheTrailofNanomagnetsElectron holography images reveal the tiniest of magnetic fields

18 HiddenTreasuresinElectronicWasteDeeper insights for the recycling industry

20 88,000KilometresforResearchGLORIA collects climate data from around the world

:: LAST BUT NOT LEAST 22

22 WhyBloggingScientistsWon’tBecomeaMassPhenomenonAn interview about scientists and social media

23 PublicationDetails

ConTenTS

166 20

32 | 2013 Research in Jülich

Research in Jülich 2 | 2013

The new electron cooler is installed at Jülich’s particle accelerator COSY.

4

nuclear Physics institute (iKP) | An electron cooler from Siberia is now boosting the performance of Jülich’s storage and accelerator ring COSY. The new device enables COSY to accel-erate electrons with a voltage as high as 2 megavolts. A maxi-mum of just 100 kilovolts was possible before. This increases the chances of detecting extremely rare high-energy decay processes. These processes play a role in the search for exotic forms of matter and effects outside the realms of the standard model of physics. The cooler was developed in cooperation with the Budker Institute of Nuclear Physics in the Russian city of Novosibirsk. ::

Cooling from SiberiaIt’s powerful, energy-effi-cient, self-learning, and self- organizing – our brain weighs less than 1.5 kg, but in terms of functionality, it outperforms any supercom-puter. For centuries, scien-

tists have been endeavouring to understand the brain. Jülich scientists are meeting this chal-lenge by means of ‘human brain modelling’ with combined efforts and state-of-the-art methods: in exploring the brain, the researchers are sup-ported by supercomputers and simulations that help them to elucidate molecular processes as well as to develop new treatments for disorders of the brain. The Jülich scientists are working on a ‘navigation system’ for the brain, for example, and on new methods for treating tinnitus and other conditions. In this issue of Research in Jülich, we would like you to join us in ‘Operation Brain’. You will also learn why six cups of coffee won’t necessarily make you feel more awake than four, what difficulties are associated with climate research at a speed of 1,000 kilometres per hour, and how Jülich researchers go treasure-hunting in electronic waste.

I hope that this issue makes for interesting reading.

Yours sincerely,Prof.AchimBachemChairman of the Board of Directorsof Forschungszentrum Jülich

:: EDITORIAL

instituteofbio-andgeosciences | The German Plant Phenotyping Network (DPPN) is currently

being established as a national infra-structure for plant sciences

and breeding. The be-

haviour, growth, and ultimately the yield of crops are determined by the interplay of their genetic properties and the environment. The DPPN is de-veloping concepts and technologies to acquire quantitative data on the relevant characteristics of plants. Finding out more about the connections will allow the researchers to breed plants with the desired characteristics. The Federal Ministry of Education and Research (BMBF) supports the pro-ject coordinated by Forschungszentrum Jülich with funding worth € 34.6 million. With DPPN,

Germany will consolidate its leading position in the area of plant phenotyping. ::

Infrastructure for Optimizing Crops

How well a carrot grows depends on the inter-play between its environment and genotype.


The Zeppelin NT on its way to Finland above the Danish capital Copenhagen

NEWS IN BRIEF

New Approach to Molecular Magnets

Filming Flow Behaviour

Self-Purification of the Atmosphere

instituteofenergyandClimateresearch| From April to late June, the Zeppelin NT is once again on a mission for climate research. Jülich scientists are employing the airship to collect data from Germany across Sweden to northern Finland that will help them find out more about the atmosphere’s ability to cleanse itself. They are focus-ing on hydroxyl radicals – OH radicals known as the ‘detergent of the atmosphere’ – and suspended particles referred to as aerosols. The measurement campaign is part of the EU project PEGASOS (Pan-European Gas-Aero sols-Climate Interaction Study), which involves 26 partners from a total of 15 countries investigating rela-tionships between atmospheric chemistry and climate change. ::

Scattering pattern of a liquid crystal under different mechanical stresses

Storing information in mini-mum space: a layer system of cobalt (bottom) and organic molecules (grey-red) ‘filters’ electrons with a specific magnetic state (green arrows).

5

Petergrünberginstitut/instituteforadvancedSimulation | Jülich scien-tists are involved in an international research team who have discovered a new method for producing molecu-lar magnets. These are molecules that remain magnetized even when an external magnetic field is switched off. The scientists are con-centrating on a thin layer system consisting of the organometallic mol-ecule zinc methyl phenalenyl (ZMP) and cobalt. These molecular mag-nets could pave the way for im-proved data storage as well as faster and more energy-efficient computer processors. The problem is that in order to exploit the effect of molecu-lar magnetism, researchers used to require temperatures far below -200 °C. The new system works even at comparatively high temperatures of -20 °C. The team have published their results in the journal Nature and are already working on optimiz-ing their system.

Petergrünberg institut/institute forad-vanced Simulation | A group of German and Dutch researchers has filmed the flow behaviour of liquid crystals with a new method. For their project, they used the X-ray radiation source PETRA III at the par-ticle accelerator centre DESY (Deutsches Elektronen-Synchrotron). The device al-lowed the scientists to record how the in-ner structure of a sample changes when it is rotated back and forth. This enabled them to explain why the material flowed or became elastic. Information on flow be-haviour is important for many areas, such as blood vessels and cement mixers, as well as the food and cosmetics industries. The group, which includes scientists from Jülich, have published their findings in the journal Physical Review Letters. ::


?Howdoesthebraincontrolourbehaviour?

Prof. Sonja Grün, Computational and Systems

Neuroscience (INM-6)

?Howisourbrainstructured?

Prof. Katrin Amunts, Structural and Functional Organization of the Brain

(INM-1)

?Whatistheroleplayedbymolecules?

Prof. Paolo Carloni, Computational Biomedicine

(IAS-5)


COVER STORY|Humanbrainmodelling

7

operationbrainThe human brain is a brilliant thinking organ. Although it is millions of years old and has been the subject of scientific interest for centuries, numerous puzzles remain to be solved by science. Supercomputers, by comparison, are relative newcomers. However, their gigantic computing power allows scientists to reveal the secrets of the human control centre. This is the objective of the research area of human brain modelling, which brings together researchers from a variety of disciplines.

?Whatcancomputerslearnfromthebrain?

Prof. Thomas Lippert, Jülich Supercomputing

Centre (JSC)

?Howcanwereconstructthebrain

onacomputer?

Dr. Boris Orth, High Performance Computing

in Neuroscience (JSC)

?Howcanwefixproblemsin

thecommunicationbetweenneurons?

Prof. Peter Tass, Neuromodulation

(INM-7)

The task of reconstructing the brain on a computer is similar in com-plexity to space travel. And the

team involved is as interdisciplinary as the ground crew supporting a space mis-sion. At Jülich alone, medical scientists, physicists, biologists, chemists, psy-

chologists, engineers, mathematicians, and computer experts work hand in hand to meet this challenge. From mole-cules and individual neurons to neuron clusters and entire areas of the brain: the researchers are analysing all the or-ganizational levels of the brain in great

detail. This is achieved using models, high-precision simulation software, and the technical infrastructure of the Jülich Supercomputing Centre (JSC). Without the mathematical prowess of the super-computers, research would only pro-gress at a snail’s pace.

Prof. Sonja Grün from the Institute of Neuroscience and Medicine (INM) depends on supercomputers to enable her to evaluate the amounts of data she pro-duces. The neuroinformatician is interested in how different areas of the brain work together, for exam-ple those responsible for visual and motor systems. What processes occur in the brain when we grab a coffee mug that’s about to tip over? Why do we lift our foot off the accelerator when we see the sign for a 30-kilometres-per-hour speed limit? In experi-ments, the scientist and her partners in France and Japan measure which neurons are activated in the different regions of the brain at what time – and what behaviour this triggers. “Neurons communi-cate via action potentials referred to as ‘spikes’ in a matter of milliseconds,” says Sonja Grün. “We can measure this transmission of electrical excitation in experiments and interpret it by analysing eye move-ments and observing behaviour.”

This may sound simple, but in fact, it’s very com-plex – and happens incredibly fast. Only 200 milli-seconds pass from one eye movement to the next – and in the meantime, numerous processing and feedback operations occur in the brain. When Grün observes a movement – from visual perception to reaction – this produces huge amounts of data. Even in the simplest experiments, each neuron is

involved in scores of simultaneous processes in the brain. The scientist develops statistical methods and software tools to make sense of this apparent chaos. ::

neuronsasTeamPlayers

Sonja Grün,neuro-

informatician

Helmholtz Research Priority

The Helmholtz Association has made the simulation of the human brain with supercomputers one of its re-search priorities. The portfolio theme ‘Supercomput-ing and Modelling for the Human Brain’ (SMHB) in-volves several Helmholtz centres together with university partners who work on scientific priorities such as simulation technology, data management, as well as structural and functional brain research. Forschungszentrum Jülich contributes through its Insti-tute of Neuroscience and Medicine (INM), the Institute for Advanced Simulation (IAS), and the Jülich Super-computing Centre (JSC), and is responsible for coordi-nating the project.


Another group of researchers at Jülich visualizes the communication pathways between neurons. Scien-tists headed by Prof. Katrin Amunts, director at the Institute of Neuroscience and Medicine (INM), have developed a method referred to as three-dimen-sional polarized light imaging (PLI) that helps them to understand the orientation of neuronal fibre tracts, the ‘hardware’ of information transmission between different brain regions. “With this three-di-mensional method of imaging the fibre tracts based on polarized light, we can produce images with a resolution in the range of thousandths of a millime-tre that are absolutely unique,” says Katrin Amunts.

This network of information pathways perfectly complements another project Amunts is involved in: mapping the entire human brain. The scientist and her team have been working on a three-dimen-sional atlas of all areas of the brain for more than 15 years. For this purpose, the researchers are analysing many thousands of ultrathin tissue sec-tions per brain using state-of-the-art microscopes and image analysis techniques before reconstruct-ing the different regions of the brain in three di-mensions. Supercomputers enable scientists to

deal with the huge amounts of data produced in this process.

However, the digital atlas contains not only infor-mation on structural differences; it also attributes functions to different areas of the brain. Around 70 % of the human brain has already been mapped. “This multimodal brain atlas can become something of a navigation system for modelling the brain,” says Amunts. It is already contributing to a better under-standing of the healthy brain, and will in future help to diagnose diseases earlier and treat them more effectively, for example. ::

Prof. Paolo Carloni and his team would not have found the 5-hydroxyindole molecule as rapidly had they used a pen and paper, or experimented in the laboratory. The molecule prevents pro-teins from clumping in the brain, causing Parkin-son’s disease. “A selection procedure on a com-puter has identified this molecule from hundreds of thousands of candidates as a suitable active substance for drugs,” says the director at the Institute for Advanced Simulation (IAS) of Forschungszentrum Jülich. Paolo Carloni looks at processes in the brain on the smallest of lev-els: the world of molecules. For example, he ob-serves how proteins in the brain react with oth-

er substances and how taste and smell molecules take effect. The pieces in this molec-ular jigsaw are important for scientists in order to obtain a complete picture of our brain’s structure and the way it works.

“Indeed molecules are our only weapon against neurodegenerative diseases such as Parkinson’s and Alzheimer’s, which spread across large areas of the brain and are therefore inoperable,” says Carloni. “The decisive factors for finding effective active substances efficient-ly are access to supercomputers and coopera-tion with laboratories to test model predic-tions.” ::


ThePoweroftheTiniestofbuildingblocks

anatlaswithnumerousFunctions

Katrin Amunts,medical scientist

Paolo Carloni,chemist

2 | 2013 Research in Jülich 9


HealthyChaosintheHeadDeveloping new treatment options is also the moti-vation for another researcher in the ‘ground crew’ of the Human Brain Project. Prof. Peter Tass, a mathematician, physicist, and medical scientist, uses knowledge from all of these disciplines to gain a better understanding of the brain, thus bridging the gap between the fundamentals of neuroscience and practical applications in the form of treatment. The director at the Institute of Neuroscience and Medicine (INM) is also interested in the communica-tion between neurons – but he studies them in sum instead of in isolation, and models them by means of mathematical algorithms. With the help of these models, he has developed a method that can cure disturbances in the communication between neu-rons, which occur in Parkinson’s and tinnitus, for example. In these conditions, neurons send infor-mation in the form of electric signals simultaneous-ly instead of one after the other, as continuous fire, so to speak. This produces the tremor in Parkin-son’s, and the continuous tone typical of tinnitus.

Tass interrupts the synchronous signals using specific electrical stimuli – with an electrode in the brain in the case of Parkinson’s and by acoustic sig-nals for tinnitus. These follow a certain pattern re-ferred to as Coordinated Reset (CR), a physical- mathematical algorithm developed by Tass, who tailors the timing of the stimuli to each individual patient. “We disturb the pathological synchroniza-tion of the neurons with electrical or acoustic im-pulses in a constructive manner”, explains Tass, “which means that we force the neurons to go back to their previous ‘healthy chaos’. This allows us to cure the symptoms of these conditions, such as movement disorders or the continuous ringing noise or at least alleviate them.”

This treatment for tinnitus patients is already of-fered at many doctors’ surgeries. The brain pace-maker for Parkinson’s patients will be used next year in trials with patients. This could help improve the existing brain pacemaker, which merely sup-presses the neural disorder. “Our innovation from Jülich is sustainable, because the brain actually learns. It memorizes the mechanism of forced de-synchronization and imitates it,” says Peter Tass. “This is why the patients’ motor skills remain im-proved even after the actual stimulation phase.” This means a glimmer of hope for those with Parkin-son’s, and shows that human brain modelling is not merely an end in itself but will, in the long term, make a contribution to enabling us to provide effec-tive treatments for neurodegenerative diseases. ::

EU Flagship ‘Human Brain Project’ Europe is pooling its scientific expertise to reach an ambitious goal: within no more than ten years, it is planned to simulate the entire human brain, from the molecular level to the interaction of entire brain regions, on a supercomputer of the future. The Human Brain Project is one of two large-scale European research projects to receive funding from the European Union under its FET Flagship programme.

The Human Brain Project brings together researchers from more than 80 scientific institutions in 23 countries. Jülich scientists from the Institute of Neuroscience and Medicine (INM), the Jülich Supercomputing Centre (JSC), and the Institute for Advanced Simulation (IAS) are sought-after experts for various Flagship research projects. This is also true for these scientists as members of the Jülich Aachen Research Alliance (JARA) of Forschungszen-trum Jülich and RWTH Aachen University, particularly in the JARA-BRAIN and JARA-High-Performance Computing sections. They are contributing their know-how on the structure and function of the brain as well as on supercomputing and simulation techniques. Experts from JSC are working with cooperation partners on the development of new computers of the exaflop generation.

Peter Tass, mathematician, physicist, and

medical scientist


The exchange between neuroscientists and IT spe-cialists is based on the principle of give and take. For example, medical scientists use the supercomputers in order to improve their understanding of the brain. However, the experts at the Jülich Supercomputing Centre (JSC) also benefit from the new findings on the brain – for example when it comes to energy efficiency: while large computing centres consume enormous amounts of electricity, the brain requires only about the same amount of power as a weak incandescent bulb. In addition, the human brain tolerates a lot more errors than a supercomputer. Although neurons die in the course of a lifetime, the brain continues to function in healthy humans. This is quite different in supercomputers: if one processor malfunctions, the re-maining 100,000 processors may also be switched off. The brain therefore serves as a model for Jülich’s IT specialists. “New findings on the function of the brain can inspire us to find new options for data pro-cessing and incorporate them in the development of

new generations of computers,” says Prof. Thomas Lippert, director at JSC. One of the creative thinking spaces for these new computer architectures is the Simulation Laboratory Neuroscience, which is head-ed by physicist and neuroscientist Prof. Abigail Mor-rison. “Our computer experts are working closely with their colleagues in neuroscience. They support them in ‘translating’ medical questions into a lan-guage the computer is able to calculate, and in this process, they are learning more every day about the brain, our ingenious information network.” ::


usingthebrainasamodel

live3dSimulationIn order to be able to map the 90 billion neurons in the brain in the future, supercomputers of the next generation will have to provide a computing power that is 1,000 times higher than that of to-day’s supercomputers, and will also need a high storage capacity and storage bandwidth. At the same time, new simulation techniques will be re-quired in order to be able to effectively exploit this computing power – a task taken care of by the research group ‘Computational Neuro- physics’ headed by Prof. Markus Diesmann. There are also completely new challenges in terms of what is simulated, explains Dr. Boris Orth from the Jülich Supercomputing Centre, who works closely with teams of neuroscientists every day. “We are currently running simulations on our computers that represent the structure and workings of individual areas,” says Boris Orth. Neuronal fibre tracts, molecular mechanisms, or spiking activities: the supercomputers simulate clearly defined tasks.

The future, however, belongs to ‘interactive supercomputing’, which incorporates all the

knowledge available, irrespective of whether it’s molecules interacting, individual brain areas communicating, or whether it’s the entire brain that’s active. It sounds like something out of Star Trek: in a few years’ time, researchers hope to be able to watch arithmetic operations in the virtual brain as they happen, in three dimensions on huge displays in a type of ‘mission control cen-tre’. “On the one hand, the huge challenge con-sists in integrating data on various levels into one single simulation,” says Boris Orth. On the other hand, simulation and visualization must take place in parallel. The advantages are obvi-ous: while the simulation is running, the re-searchers can zoom in on certain areas, even the molecular level, as with a telescope, in order to change simulation settings there if necessary. In this way, it would be possible to observe and test the effects of drugs and other treatments such as neurostimulation directly in the brain – which would be a milestone for drug development and brain researchers comparable to the first step on the moon. ::

Thomas Lippert, physicist

Boris Orth, physicist

Ilse Trautwein

12

Ping-pong balls, soap bubbles, Christ-mas tree decorations – we all know spherical shells from our everyday

lives. However, it is a less well-known fact that such shells are also used in nano- technology: as microscopically small capsules that release their contents at the right time and the right place. For ex-ample, medical scientists have made good progress in their plans to use microcapsules the size of a blood cell to deliver drugs exactly where they are to take effect instead of distributing them in the entire body, which is the case when you take them in the form of tab-lets. Odoriferous substances and insec-


ticides could also be transported in this targeted manner.

However, it is not known exactly how shells will behave when they are shrunk to a size of only a few micrometres. “There are many theories to describe what happens on a large scale, but quite often these no longer apply on a smaller scale”, says Gerard Vliegen-thart, “because there are effects that are irrelevant on a large scale but make a big difference in the microworld. We are extending the theoretical structure of physics onto the microscopic level.” At the Institute for Complex Systems (ICS), he and Gerhard Gompper are

looking into such an effect – thermal fluctuations – and investigating its im-pact on the stability of shells small enough to be considered by medical scientists for use as microcapsules. To-gether with colleagues from Harvard, they were able to confirm their assump-tion that, due to these thermal fluctua-tions, microcapsules are considerably less stable than previously believed.

HeaTCreaSeSSurFaCeThermal fluctuations are a type of back-ground noise of matter. “Atoms only stand still at absolute zero. Otherwise, they hop around their basic position and

Spherical shells are useful for many purposes. For examples, medical scientists hope to be able to use them as microcapsules releasing drugs in a selective manner. Jülich researchers have now found out that these ‘nanoferries’ are significantly less stable than previously assumed.


become more hectic the higher the tem-perature,” explains Gompper. The vibrat-ing molecules hit the surface of a shell like billiard balls, for example when they swim through water. This sustained fire has no effect on larger shells, such as ping-pong balls or bathyspheres. In mi-croscopically small shells, however, ther-mal fluctuations change the surface.

Gompper illustrates this fact by scrunching up a piece of paper and then smoothing it out. The paper now resem-bles a hilly landscape with randomly dis-tributed ridges and valleys. “This is roughly what you can imagine the sur-face of a microcapsule to look like when it has been deformed by thermal fluctua-tions.”

Paper can also be used to demon-strate that the consequences are not merely of an aesthetic nature. Gompper holds a smooth piece of paper at its short edge and swings it like a pendu-lum. The paper bends, it’s elastic. Then he repeats the same movement with the scrunched piece of paper. It remains rig-id. “Smooth and crumpled surfaces have different properties. One of them is stiff-ness. We have studied the influence of this property on the stability of shells.”

In order to measure how stable a shell is, pressure tests are usually car-ried out. These are comparable to press-ing a ping-pong ball with your thumb re-peatedly until it is permanently dented. The necessary force can be calculated

using a formula developed by the fa-mous mathematician, aerospace engi-neer, and physicist Theodore von Kármán more than 50 years ago. Gomp-per and Vliegenthart have now tested whether this formula also applies when the shells have a diameter of less than 10 micrometres.

VirTualeXPerimenTSFor this purpose, the physicists mod-elled a virtual shell on a computer, simu-lated the effects of thermal fluctuation, and performed virtual pressure tests. Whereas the colleagues overseas are working on a theory that numerically de-scribes the effects of the deformed sur-face, scientists at Jülich are primarily using simulation methods and computer models.

“We already simulated a plane with an elastic and crumpled surface seven years ago. This was our point of departure for developing a virtu-al shell with this chaotic sur-face,” says Vliegenthart. Modelling, he says, was the hardest part of the work: Vliegenthart con-structed a shell con-sisting of 100,000 grid points, each of them connected to its neighbours on the surface via springs. He then

performed virtual experiments: as in a real pressure test, he applied pressure to points or larger areas on the shell until it collapsed. This experiment was repeated under different conditions to measure the critical pressure.

The result: depending on the size, material, and shell thickness, up to 50 % less force is required than predicted by Kármán’s equation – a finding that will be taken into consideration by scien-tists involved in the development of nanoferries. ::

Christoph Mann

RESEARCH AT THE CENTRE|Simulation

Thermal fluctuations mean that atoms are always on the move, and collide with nearby surfaces in the process. This has no effect on larg-er shells, such as ping-pong balls, but the surface of tiny shells such as microcapsules is crumpled when continuously bombarded with atoms (image 1). As a conse-quence, the microcapsules are less resistant to pressure and collapse more easily (image 2).

adentinthesphere

Image 2

Image 1


Legend has it that it was a herd of goats in the Kingdom of Kaffa – in what’s Ethiopia today – that discov-

ered the stimulating effect of coffee more than a thousand years ago. In the middle of the night, the animals were still wide awake after having eaten from the red berries of a certain shrub. The shepherds were amazed. They tried the fruits for themselves and then they, too, were able to turn night into day. Roast-ed, ground, and brewed as an aromatic beverage, coffee beans conquered the

Coffee helps us to stay awake when we feel overwhelmed by tiredness. A cup of coffee or two cannot make up for lack of sleep, but it does postpone the moment where we surrender to exhaustion. A team headed by Jülich neuroscientist Prof. Andreas Bauer has now discovered the mechanism behind this effect.

Prof. Andreas Bauer, director at the Institute of Neuroscience and Medicine (INM), investigates the effect of coffee in the brain by means of imaging techniques.

world from the 17th century onwards. Caffeine has long been the world’s most widely consumed psychoactive sub-stance. Why the brew has its energizing effect is only recently coming to light.

bloCKedSleePSignalWhether simple filter coffee or Italian es-presso, French café au lait, or Spanish cortado is simply a matter of taste. The way in which they make us feel wide awake, however, is the same for all of them, explains Andreas Bauer, director at the Institute of Neuroscience and Medicine (INM): “The caffeine binds to adenosine receptors in the membrane of neurons in various regions of the brain. In this way, it blocks the receptor for its proper partner, the signal molecule adenosine.” Adenosine accumulates in the body during prolonged phases of sleep deprivation. When it binds to the appropriate receptor, the activity of the neurons is reduced – for the body, this is a sign to fall asleep. “However, if the re-ceptor is already occupied by caffeine, the information that the body is tired does not reach its destination and you stay awake longer,” says Bauer, who en-joys a cup of coffee himself.

The Jülich scientists wanted to find out more about where exactly the pick-me-up takes effect in the brain. This is why they administered a radioactively labelled molecule known as 18F-CPFPX to 15 volunteers. It binds to a certain type of adenosine receptor: the A1 re-ceptor. The researchers then determined where the labelled molecule accumu-lates in the brain and in what concentra-tion by means of positron emission tomography (PET). The participants were subsequently given different amounts of caffeine – unfortunately not in the form of a hot drink, but by injection directly into the blood stream. “Only in this way can we adjust a precisely defined con-centration of caffeine in the volunteers’ blood,” says Bauer. The caffeine reached the brain, where it crowded out the radioactive marker molecule from the receptor – and in doing so, it was sur-prisingly efficient. “Even the amount of caffeine contained in four to five cups of coffee is enough to occupy half of the A1 receptors. Drinking even more coffee, however, does not make sense. “This intensifies the side effects, such as nervousness or even an increased heart rate.” The reason is that receptors for caffeine can also be found in the heart. However, a habituation effect will set in after some time: if you regularly drink large amounts of coffee, you will eventu-ally have to drink even more in order to stay awake.

The PET examination also revealed the regions of the brain in which the caf-

15

RESEARCH AT THE CENTRE|brainresearch


feine replaced the radioactive molecules in the A1 receptors. They discovered that it binds to three particularly inter-esting areas. These include the thalamus – sometimes referred to as the ‘gate to the cerebral cortex’ and influences the readiness of the brain to take in informa-tion, the hippocampus, which plays an important role in the transfer of informa-tion from short-time memory to long-term memory, and finally, parts of the cerebral cortex referred to as the associ-ation cortex. “This is where information from different brain regions comes to-gether, where thoughts are ‘juggled’, so to say, and where our new ideas proba-bly come from,” says Bauer. This could explain why coffee is not only a treat,

but also a means of temporarily increas-ing the performance of the brain.

ConTribuTionToalZHeimer’SreSearCHThe association cortex is also the part of the cerebrum where an infamous decay process of the brain has a particularly devastating effect: Alzheimer’s disease. There are epidemiological studies that suggest coffee drinkers are less likely to get Alzheimer’s disease, which means that coffee could have a certain protec-tive effect. Bauer is hopeful: “Studying the molecular effects of caffeine, par-ticularly in the cerebral cortex, may help to develop drugs to prevent Alzheimer’s disease.” In his work, Bauer is cooperat-

ing closely with his Jülich colleagues in the area of nuclear chemistry, who are developing a new, even more specific adenosine ligand, and with Prof. Paolo Carloni and his team from the Institute for Advanced Simulation (IAS), who are approximating the complex molecular interactions of caffeine and its receptors by means of simulations on Jülich’s su-percomputer. ::

Wiebke Rögener

Wherecaffeinetakeseffect

3

2

1

Caffeine binds to so-called A1 re-ceptors in three regions of the brain, where it unfolds its stimulat-ing effects:

1 Cerebral cortex 2 Thalamus 3 Hippocampus

16 Research in Jülich 2 | 2013

The Ernst Ruska-Centre (ER-C) is home to the most powerful electron microscopes worldwide, which pro-vide very exact images of the arrangement of atoms in materials. The researchers headed by Prof. Rafal Dunin- Borkowski will also use the devices for other purposes in future. They will make visible tiny magnetic fields in-side nanoparticles with unprecedented clarity. This will benefit information technology and other fields.

HotontheTrailofnanomagnets

In 1831, the famous English scientist Michael Faraday was the first to demonstrate what was to become a

standard experiment for generations of school students in their physics classes. Faraday placed a piece of paper on top of a magnet and poured iron filings on it. As if by magic, these filings formed a pattern of lines on the paper – proof of the existence of magnetic field lines. Prof. Rafal Dunin-Borkowski, director at

Prof. Rafal Dunin-Borkowski is exploring the magnetism of nanoparticles with the help of electron holography.

with a diameter of no more than 180 mil-lionths of a millimetre (nanometres).

uniQuePoSSibiliTieSDunin-Borkowski and other researchers took this image with an electron microscope. The scientists used a special type of electron microscopy referred to as electron holography (see image ‘How electron holography works’). “Although this method opens up unique possibilities for exploring the magnetic properties of nanomaterials, it is only used by a handful of research groups worldwide,” says Dunin-Borkowski. This is all the more surprising given that the magnetism in nanometre dimensions is decisive for the function of materials that are used, for example, in medicine, for catalysis, and waste water treatment.

“However, being able to measure and understand magnetic fields in materials on the nanometre scale is important in particular for information technologies of the future,” says Dunin-Borkowski.

the Ernst Ruska-Centre and at Jülich’s Peter Grünberg Institute (PGI) is, in some way, following in Faraday’s foot-steps. He likes to show visitors an image that is very similar to that of a bar mag-net with field lines. And indeed it shows a magnetic field pattern. However, what’s really interesting about this im-age is that the field is not produced by an object that’s visible to the naked eye, but by an iron crystal in a carbon tube


RESEARCH AT THE CENTRE|electronmicroscopy

For example, many researchers are cur-rently working on what is referred to as spintronics. They no longer want to rely solely on the charge of electrons for in-formation processing, but also their an-gular momentum, also known as their spin. Using the spin, researchers are planning to make much more energy- efficient and faster computers a reality. As the spin of electrons is linked to a magnetic moment, electron holography could theoretically make visible the arrangement of spins inside nanomaterials.

aTTHelimiTHowever, the method is currently reach-ing its limits. Despite its matchless reso-lution, it is not yet good enough for this purpose. So far, two field lines must be at least five nanometres apart in order for electron holography to show them as separate lines. In addition, the magnetic fields to be measured are very weak, particularly in particles with a diameter of less than 20 nanometres.

This is the reason why another ques-tion of information technology currently remains unanswered: can data be stored securely in magnetic nanocrystallites consisting of only a few dozen atoms? The corresponding units in today’s com-puter hard disks are considerably larger, but with increasing miniaturization, this issue is becoming more and more ur-gent.

With a view to practically relevant problems such as this, Dunin- Borkowski has been devoting himself to the task of making electron holography more sensi-tive and improving its resolution for many years. He came to ER-C, which is operat-ed jointly by Forschungszentrum Jülich

Any electron microscope can be used for the purpose of electron holography, provided that it has a field emission gun (FEG), a special source of electron emission. A bi-prism is also required as special equipment. This gold-plated quartz glass fibre is installed in place of one of the apertures of a conven-tional electron microscope.

The electron beam from the field emission gun is bisected in the microscope. One half serves as a reference, the other is directed through the specimen. The biprism, to which an electrical potential is applied, then deflects the two elec-tron beams so that they overlap. This results in an interference pat-tern – the hologram. It contains in-formation on the magnetic fields in the specimen.

How electron holography works

Field emission gun (FEG)

Reference beam

Biprism

Hologram

Specimen

and RWTH Aachen University under the umbrella of the Jülich Aachen Research Alliance (JARA), in 2011. What he found here are ideal conditions for breaking new ground in his research: PICO at ER-C is one of only two microscopes of its kind in the world. They have special elements that are able to correct a lens error known as chromatic aberration. This al-lows PICO to image the arrangement of atoms inside crystals with unprecedented accuracy.

Dunin-Borkowski hopes to repeat this success story with electron holography, using corrective lenses to improve this method, too. The European Research Council has faith in him. In late 2012, it provided Dunin-Borkowski with an Ad-vanced Grant, which is worth € 2.5 million in funding over a period of five years. ::

Dr. Frank Frick

Iron filings can make visible the field lines of a bar magnet about a centimetre in size.

This magnet – an iron crystal in a carbon tube – has a diameter of 180 nanometres. Electron holography makes it possible to see the lines of force of a nanomagnet.


What contains more gold: the ore in a goldmine, circuit boards in computers, or mobile phones?

Astonishingly, 1,000 kilograms of ore contains no more than an average of 5 grams of gold, while 1,000 kilograms of circuit boards in contrast contains 250 grams, and 1,000 kilograms of mobile phones up to 350 grams. As if that weren’t enough, mobile phones and other electronic devices also contain other elements, such as silver, palladium, iridium and copper.

In other words, it looks like it would be worth mining electronic waste for gold and other noble metals. However, in practice, recycling is no easy task. The old devices must be collected as effec-tively as possible, sorted and then taken apart. And in addition, electronic waste contains several harmful substances, which must be completely removed and disposed of separately.

“For the recycling industry, it’s impor-tant to know what valuable materials are contained in a batch of waste as well as in what quantities,” says Dr. Andrea Mahr from Technology Transfer (T) at For-schungszentrum Jülich. She has been in-volved in numerous discussions with com-panies and associations from the recycling sector as well as the electronics industry since 2011. The reason: she was sounding out the market for an analysis technique developed by scientists at Jülich’s Insti-tute of Energy and Climate Research (IEK) and RWTH Aachen University, originally for a very different application.

HiddenTreasuresinelectronicWasteJülich scientists originally developed the measuring technique MEDINA for the non- destructive analysis of the contents of drums with low-level radioactive waste to be sent to the approved final storage facility Schacht Konrad. They are now planning to fit MEDINA up for another task: determining the noble metal content in electronic waste. This would allow recycling companies to discover more efficiently whether it is worthwhile recovering these valuable materials.

eXaminingunoPeneddrumS“In 2007, we were trying to find a way to identify the contents of drums contain-ing low-level radioactive waste from in-dustry, research, and medicine without

FromwastetosourceofrawmaterialsA tonne of old mobile phones contains material that is worth around € 10,000 in total:

120kgcopper

2.5kgsilver


involves a neutron beam that briefly acti-vates the atomic nuclei in the material to be analysed. The activated nuclei react promptly – within a maximum of a tril-lionth of a second – by emitting gamma radiation characteristic of each element. The result is a spectrum of signals, the position and amplitude of which provide information on the type and quantity of the elements contained in a drum.

In the subsequent period, Mauerhofer and his then PhD student John Kettler, who now works at the Institute of Nuclear Fuel Cycle at RWTH Aachen Uni-versity, set up a test facility, initially for 100-litre drums, and later, with PhD stu-dent Andreas Havenith, for 200-litre drums. This facility included a commer-cial neutron source. The rod-shaped de-vice irradiates the specimen with neu-trons, electrically neutral building blocks of atomic nuclei that do not occur natu-rally in isolation. Further components of the facility include a graphite chamber that decelerates the neutrons and re-flects them, and a detector that mea-sures the prompt gamma radiation of the specimen.

PaTenTPendingThe team headed by Mauerhofer invest-ed the most time and energy in the de-velopment of software that delivers nu-merical values for the composition of elements from the gamma spectrum obtained. A patent application has been filed for the new analysis technique. The scientists named the entire method MEDINA, which is short for ‘Multi- Element Detection based on Instrumen-tal Neutron Activation’.

Mauerhofer is familiar with the reser-vations that crop up when people hear about the planned use of MEDINA for the analysis of electronic waste. “Yes, radiation protection measures are nec-essary,” he confirms. But, he continues, similar measures are also necessary in doctors’ surgeries and medical laborato-ries when taking X-rays or handling radio active substances. “In addition, the radioactivity of the investigated materi-als no longer exceeds the natural radio-activity of a potato, for example, only half an hour after the measurement,” says Mauerhofer.

He is convinced that MEDINA is much more efficient than conventional

analysis techniques: “The latter require a lot of staff and time, not to mention the chemicals and energy that are needed for wet-chemical sample prepa-ration.” Above all, however, MEDINA does away with the need for the com-plex sampling process involved in tech-niques currently used. MEDINA would allow waste to be screened automati-cally on a conveyor belt for valuable ma-terials, so to speak. However, for this scenario to become reality, the scien-tists are reliant on support from indus-try. They have to adapt MEDINA to suit the needs of the recycling sector in terms of detection limits and reliability of analyses. Technology transfer expert Mahr is optimistic: “The interest is there, and we’re already in concrete ne-gotiations with one company on joint further development.” ::

Dr. Frank Frick

RESEARCH AT THE CENTRE|innovations

having to open them,” says Dr. Eric Mauerhofer from IEK. According to cur-rent planning, these drums will be taken to Schacht Konrad near the town of Salzgitter for final disposal from 2019. They contain radioactive elements as well as toxic agents, including lead, cad-mium, and mercury. The regulatory au-thorities have set limits for their final disposal that must be met – this is the reason for the search for a safe and in-expensive method of analysing the con-tents of these drums.

Mauerhofer was convinced that a measuring technique he was familiar with could do the trick: prompt gamma neutron activation analysis. This method

Dr. Andrea Mahr has sounded out the market for the new technology.

Dr. Eric Mauerhofer has developed the MEDINA measuring technique and is now planning to fit it up for efficiently analys-ing electronic waste.

300ggold

100gpalladium

20 Research in Jülich 2 | 2013

On 30 August 2012, this success is not yet foreseeable. GLORIA is flying at an altitude of 15 kilo-

metres over the Atlantic Ocean west of the French coast. The outside tem-perature is -50 °C. Erik Kretschmer re-presents the GLORIA team on board the new German research aircraft HALO. The systems engineer from the Karls-ruhe Institute of Technology (KIT) is responsible for the smooth operation of the spectrometer during the ongoing atmospheric measurement campaign.

Every single flight hour is precious – but Kretschmer has just been instructed by the pilots to switch GLORIA off.

Radio communication is disrupted, and the pilots suspect that this is GLO-RIA’s fault. The reason for their suspicion is that the spectrometer is installed out-side on the fuselage in what is referred to as a ‘bellypod’ – in the direct vicinity of the radio antenna. If Kretschmer switch-es GLORIA off, it will be only a matter of minutes until the spectrometer has cooled down and the sensitive electron-

ics are exposed to the bitter cold. But air safety is the top priority. Kretschmer switches the device off and cuts off the energy supply. GLORIA is a masterpiece created by experts from Karlsruhe and Jülich. The initial idea came from atmos-pheric researcher Prof. Martin Riese, di-rector at Jülich’s Institute of Energy and Climate Research (IEK), and Felix Friedl-Vallon, physicist at KIT. Riese was planning to measure a large range of cli-mate-relevant trace gases in unprece-dented spatial resolution with novel de-

88,000KilometresforresearchAbout 30 terabytes of data for climate research: that’s the result of 88,000 kilometres flown in 126 flight hours with the new spectrometer GLORIA in autumn 2012 – a fantastic result for the scientists and engineers involved.

Enjoying the evening sun in Cyprus for a moment before the night shift begins: Martin Zögner from the German Aerospace Center (DLR) is monitoring all work on the research aircraft while HALO is on the runway. The enormous amounts of data collected during the previous flight must now be securely stored overnight. This process takes several hours and requires the ground crew to be highly focused.


tector chips. Friedl-Vallon suggested using an imaging Fourier spectrometer.

Atmospheric researchers from both institutions were involved in the techni-cal development right from the start. The optical system was developed at Karlsruhe, while specialists from Jülich developed and fabricated the appropri-ate electronics and mechanics. Reading out and processing more than ten mil-lion units of information per second is a challenge.

beadCurTaininTHeSKYGLORIA is able to keep a measuring field steady within 50 metres on the horizon for ten seconds. Each measurement maps a vertical area of four kilometres up to the flying altitude. The points of each measurement are beaded together like a string of pearls. The next measure-ment is taken ten seconds later: target-ing the next field, holding for ten sec-onds, and then taking the measurement, heading for the next field, holding, meas-uring... The result resembles a bead cur-tain consisting of several million measur-ing points. This provides the researchers with a complete picture of the chemical composition of the targeted air masses.

But GLORIA can do much more than that: if the aircraft flies in a large closed hexagon, the spectrometer turns into a three-dimensional tomography system. Dr. Peter Preusse from Jülich’s Institute of Energy and Climate Research (IEK) says, “This enables us to see the struc-ture of fluxes between the troposphere and stratosphere in three dimensions.”

Prof. Martin Riese, Erik Kretschmer, and Felix Friedl-Vallon (from left to right) are enthusiastic about the huge amounts of data brought home by GLORIA from the most recent measurement campaigns. The secret to success: outstanding teamwork between all the institutions involved.

However, on this day, 30 August, GLORIA is no longer in operation. “GLO-RIA had been tested and given clear-ance, also for electromagnetic interfer-ence fields,” says Tom Neubert from Jülich’s Central Institute of Engineering, Electronics and Analytics (ZEA). And in-deed, the pilots soon give the all-clear signal. The reason was obviously some-thing else, and GLORIA can be switched on again. But how? GLORIA has cooled down too much. The sensitive electron-ics have packed up.

SimPleTriCKBoth the ground crew and Erik Kretsch-mer are working feverishly to find a solution. The aircraft is reducing the flight level in order to enter warmer lay-ers of air. “We then asked Erik to switch on different units of GLORIA one after the other in order to produce heat first. By switching on the ventilators that are usually responsible for cooling, we dis-tributed the heat in the spectrometer,” says Tom Neubert. Success! From then on, GLORIA continues to reliably acquire data on the content of carbon dioxide, methane, ozone, water vapour, as well as numerous nitrogen and chlorine com-

GLORIA stands for ‘Gimballed Limb Observer for Radiance Imaging of the Atmosphere’. It’s the name of a novel infrared camera that breaks down the heat radiation of atmospheric gases and aerosols into its spectral colours. The images produced show the large-scale movements of the different components of the atmosphere. GLORIA’s measurements include CO2, methane, ozone, water vapour, and numerous nitrogen and chlorine compounds. It is the prototype of a spectro-meter that could also be used on a satellite.

pounds in the boundary region between the troposphere and the stratosphere.

The flight routes of the measurement campaigns in autumn 2012 stretched from the Arctic Circle to the Svalbard ar-chipelago and around Africa to the Ant-arctic Circle. On every one of its flights, GLORIA collects one to two terabytes of data. The total sum will be 30 terabytes, which corresponds roughly to the amounts of data contained in three mil-lion encyclopaedias.

neWdeTailSThe detailed analysis of the data is ex-pected to take at least until autumn 2013. Dr. Peter Preusse says, “Initial re-sults from GLORIA show that tropo-spheric and stratospheric air masses do not mix evenly. We found more pro-nounced structures than predicted by models. We observed the formation of filaments that are several 100 to 1,000 kilometres long, but only have a low ex-tent in altitude. GLORIA’s particularly high resolution allows us to observe these fine patterns in more detail than ever before.” ::

Brigitte Stahl-Busse

masterpieceforclimateresearch

RESEARCH AT THE CENTRE|Climateresearch

Research in Jülich 2 | 201322 Research in Jülich 2 | 201322

areweabouttoexperiencearevolutioninscientificcommu-nication?Peters: We are certainly experiencing a time of change. The Internet represents a historic turning point in the media world. People use media differently. Today, scientists are expected to be visible in the public arena. However, from my point of view, this doesn’t mean that the system will be revolutionized.

aren’tscientistsexcitedaboutmakinguseofnewopportuni-ties,suchasblogs,andaddressingthepublicdirectly,with-outjournalistsactingasintermediaries?Peters: Apparently, that’s not the case for the majority of them: the neuroscientists in Germany and the USA who were part of one of our surveys, for example, said that when they read up about science in general, they primarily fell back on journalistic media. They also believed that these traditional media had more influence than new media, and to them, appearing in a renowned medium had greater significance and impact than writing about their views in their own blog. It is doubtful whether many researchers will take the time for extensive on-line activities. In addition, even on the Internet the public will not be able to do without journalism or something else that helps to gauge the significance of a topic.

do scientists really want to be in direct contact with thepublic?Peters: Scientists are certainly interested in engaging in a dia-logue with the public. However, the majority of them object to giving lay people more influence on decision-making processes within the science community. Our studies show that natural scientists in particular clearly differentiate between discus-sions within the community and discussions with the public.

Then this is why there will be no revolution. From yourperspective,whatarethemostinfluentialtrends?Peters: Our study with the neuroscientists in particular revealed that scientists want to make their public relations ac-tivities more efficient. They are beginning to select those me-dia that are most important and to delegate PR tasks to public relations departments or external agencies. For interested members of the public, however, there is the danger that PR material could become dominant in comparison to critical and balanced reports. In addition, the expectations that the general public has of science are increasingly communicated directly and interactively, for example by shitstorms against certain areas of research or by influencing areas such as climate research via blogs.

The signs are pointing towards change, also for scientific communication. There are experts who are certain that the future belongs to blogs and social networking sites and that traditional science journalism will soon be a thing of the past. However, Jülich communication scientist Prof. Hans Peter Peters is sceptical. He conducted surveys of scientists worldwide as part of several studies.

WhybloggingScientistsWon’tbecomeamassPhenomenon


LAST BUT NOT LEAST

The interview was conducted by Christian Hohlfeld.

Prof. Hans Peter Peters from Ethics in the Neuro-sciences (INM-8) investigates the relationship between science and the public.

23

PubliCaTiondeTailS

researchinJülich Magazine of For schungszentrum Jülich, ISSN 1433-7371 Publishedby: Forschungszen trum Jülich GmbH | 52425 Jülich | Germany Conceptionandeditorialwork: Annette Stettien, Dr. Barbara Schunk, Dr. Anne Rother (responsible according to German press law) authors: Dr. Frank Frick, Christian Hohlfeld, Christoph Mann, Wiebke Rögener-Schwarz, Tobias Schlösser, Dr. Barbara Schunk, Brigitte Stahl-Busse, Ilse Trautwein, Annette Stettien, Angela Wenzik graphicsandlayout: SeitenPlan GmbH, Corporate Publishing, Dortmund Translation: Language Services, Forschungszentrum Jülich images: Aero-Art Frank Herzog (3 top right), Africa Studio/Shutterstock.com (13 large ball), Amunts, Bludau, Mohlberg/Forschungszentrum Jülich (9 centre), Amunts, Zilles, Axer et al./Forschungszentrum Jülich (8 bottom), Angew. Chemie 42 (2003), 5591-5593 (3 top centre), Awe Inspiring Images/Shutterstock.com (17 top left), Bakalusha/Shutterstock.com (18), CLIPAERA 1 Custom media/Shutterstock.com (15 brain), Cyborg-witch/Shutterstock.com (1, 6, 7), dotshock/Shutterstock.com (22–23 background), Dr. Peter Preusse (20), DyMax/Shutterstock.com (22–23 mug), ER-C/Forschungszentrum Jülich (Acknowledgements: Takeshi Kasama, Rafal Dunin-Borkowski, Krzysztof Koziol, Alan Windle) (17 top centre), Forschungszentrum Jülich (2, 4 top left and centre left, 5, 8 top, 9 top and bottom, 10, 11 top and bottom, 12, 13 bottom left, 14, 15 top right, 16 top right, 17 bottom, 19, 21 bottom, 23 top right), frotos/Shutterstock.com (22–23 monitor), JARA-HPC (11 centre), KIT/M. Lober (21 top), Nattika/Shutterstock.com (4 bottom left), Oleksiy Mark/Shutterstock.com (16 top left), Peter Winandy (3 top left), Reinhold Leitner/Shutterstock.com (22–23 table), Zffoto/Shutterstock.com (22–23 monitor background) Contact: Corporate Communications | Tel: +49 2461 61-4661 | Fax: +49 2461 61-4666 | Email: [email protected]


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