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effzett FORSCHUNGSZENTRUM JÜLICH’S MAGAZINE
Slow and steady Why science takes its time
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HIGH CONTENT
QUICK ROUTE
FAST ESCAPE
Nitrate pollutes groundwater
How blood cells move through our veins
Fire in underground train stations
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AS W E S E E IT
Outcast into the desert Sand, bare hills, rocks – the Atacama Desert in Chile is one of the driest places on Earth. Jülich scientists have set up their measuring instruments in the middle of this desolate location. They aim to find out the composition of soils in Chile – something we know little about. Igor Dal Bo (sitting), doctoral researcher at the Institute of Bio- and Geosciences (IBG-3), measures electrical currents in the soil. This permits conclusions to be drawn about the various rock strata several metres underground. In addition, the researchers also take soil samples. The work is part of the German–Chilean EarthShape project.
TO PI C S
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Chewing the cud
N E W S IN B R IE F
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Slow and steady wins the race
Always in good shape Whenever it gets too cramped, red blood cells simply deform.
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What does an axion weigh? Mysteries of space: on the search for an elementary particle
19 Science takes its time. Whether it’s climate research or medicine: how fast science progresses depends on many factors.
Nitrate contaminates our groundwater
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A matter of taste Paolo Carloni investigates how bitter substances work in our body
Trip to the underworld
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SECTIONS
Editorial
RESEARCH
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Two souls, alas!, reside within his breast
Publication details 4
What’s your research all about? 23
2.2 plus 30
Thumbs up
Bernd Mohr on the big stage and in private
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31 Better fire protection in underground stations
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Research in a tweet 32
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E D I TO R I A L
30 seconds … that’s about how long it will take you to read this editorial. In that time, you could wash your hands thoroughly, pay for your shopping by card or go from 0 to 300 km/h in a tuned Porsche 911.
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Science, in contrast, usually takes a bit longer – sometimes even decades. For example, scientists were unable to detect the famous Higgs boson until 2012 – almost 50 years after its existence had been predicted. One of the reasons for the long wait was that suitable measurement technology was not available – after all, the particle decays after just 10 – 22 seconds. But not all natural processes occur very fast: some take a more leisurely pace. This in turn also slows down the acquisition of knowledge. It also takes considerable time if researchers have to collect data over years in order to get a clear picture. Intensive research thus sometimes requires patience and perseverance as the examples of climate research and medicine in our cover story reveal. If you have a bit of free time on your hands, why not read about how Jülich researchers are helping to evacuate underground train stations in the event of fire (reading time: about 1.5 minutes), how the body stops veins from clogging up (reading time: about 1.5 minutes), and what is polluting our groundwater (reading time: about 2.5 minutes). We hope you enjoy every minute of reading this issue! Your effzett editorial team
Publication details effzett Forschungszentrum Jülich’s magazine ISSN 1433-7371 Published by: Forschungszentrum Jülich GmbH, 52425 Jülich, Germany Conception and editorial work: Annette Stettien, Dr. Barbara Schunk, Christian Hohlfeld, Dr. Anne Rother (responsible under German Press Law) Authors: Marcel Bülow, Dr. Frank Frick, Christian Hohlfeld, Dr. Jens Kube, Katja Lüers, Dr. Regine Panknin, Dr. Barbara Schunk, Seitenplan, Brigitte Stahl-Busse, Jochen Steiner, Dr. Janine van Acker en, Angela Wenzik, Erhard Zeiss, Peter Zekert Graphics and layout: SeitenPlan GmbH, Corporate Publishing Dortmund, Germany
Images: Forschungszentrum Jülich (3 top centre, 5 bottom and 16 top (blood cells), 13 bottom, 22 bottom right, 26 bottom); Forschungszen trum Jülich/Lukas Arnold (22 bottom left); Forschungszentrum Jülich/Anja Klotzsche (2); Forschungszentrum Jülich/Sascha Kreklau (23, 28); Forschungszentrum Jülich/Ralf-Uwe Limbach (18 top, 22 top, 26 top, 27 bottom, 32); Forschungszentrum Jülich/Regine Panknin (5 top); Ralf Eisenbach (3 bottom centre, 20–21); Niels Fischer/Max Planck Institute for Biophysical Chemistry, image editing: Seitenplan (6 bottom); Förderverein John-Cage-Orgel-Kunst-Projekt e. V. (11) Lufthansa image archive (12 top); SC16 Con ference, Jo Ramsey (3 bottom left, 15); Wolfram Scheible (14 right); Screenshot WDR: Evolution in 24 Stunden, Planet Wissen, 1 March 2017, http://www.planet-wissen.de/video-evolutionin--stunden-100.html (31); University_of_Queens land_Pitch_drop_experiment.jpg: John Mainstone, derivative work: Amada44 (https://commons.
wikimedia.org/wiki/File: University_of_Queens land_Pitch_drop_experiment-white_bg.jpg), “Uni versity of Queensland Pitch drop experiment-white bg”, https://creativecommons.org/licenses/ by-sa/3.0/legalcode (10 bottom); the following all from Shutterstock.com: Aphelleon (19); image agency Zoonar GmbH (25 top); Suttha Burawonk (6 top); colores (30); goir (4 (mobile phone)); Happy Artk (29); iurii (14 left); Dudarev Mikhail (3 right, 24–27 (background image)); Christian Muel ler (27 top left); Mopic (10 top); MPanchenko (27 top right); Eric Isselee (12 bottom left); Romanova Natali (7 right); Viorel Sima (12 bottom right); somersault1824 (16–17); SuriyaPhoto (4 (laptop)); Tyler W. Stipp (13 top); Teun van den Dries (7 left); YAKPHOTO (1, 3 top left, 9) Contact: Corporate Communications Tel: +49 2461 61-46 61, Fax: +49 2461 61-4666 Email: info@fz-juelich.de
N E WS IN B R IE F
B I O LO GY
Inside and outside Plants often develop in a completely different way in greenhouses or climate chambers than they do in the field. They grow faster but have thinner leaves. How d ifferent conditions, such as light and temperature, influence their growth has been summarized by researchers from Jülich, Oldenburg, and the Netherlands. This knowledge is important in order to transfer results from such test facilities to outdoor fields. – INSTITUTE OF BIO - AND GEOSCIENCES –
M AT E R I A L S R E S E A R C H
Microscopic magnets It was conventionally viewed as unusable: the combination of organic substances and rare earths, a special group of metals. Jülich researchers together with colleagues from Stuttgart and Great Britain have now found out that, under certain circumstances, the electron structure of the metal atoms can be influenced – and with it their magnetic properties. And it is precisely these properties that are decisive when it comes to whether or not a metal is suitable for molecular magnets. These tiny magnets consisting of metal atoms and organic molecules are viewed as promising candidates for bits in future quantum computers. – PETER GRÜNBERG INSTITUTE –
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Artificial bone healing Biomaterials could in future help heal serious bone injuries. One of these materials is ArcGel, a novel polymer developed at Helmholtz-Zentrum Geesthacht. Jülich researchers were able to show that it is superior to commercially available materials and that it can heal injuries just as well as the body’s own bone material. The latter is conventionally used in the case of serious bone damage. However, for this purpose, it must be removed from another point in the body, which harbours an additional surgical risk for the patient. – INSTITUTE OF NEUROSCIENCE AND MEDICINE –
B I O C H E M I S T RY
Building at a signal All living cells comprise ribosomes – complex molecular machines which produce proteins. Jülich and Göttingen researchers were able to show for the first time how ribosomes succeed in correctly assembling the proteins so that individual amino acids are combined in a precisely prescribed order in terms of their genetics. The scientists verified with atomic accuracy how the necessary signals are forwarded within the ribosome. – INSTITUTE OF COMPLE X SYSTEMS –
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M E D I C IN E
Loss of function
P2X
Protein aggregations in the brain are viewed as a decisive trigger of Alzheimer’s disease. Jülich and Düsseldorf scientists have now discovered that it’s not only the aggregation of the beta amyloid protein that is problematic. The protein also loses its ability to bind to an important component of the nerve cell membrane. This component is involved in many neuronal processes. The researchers now want to investigate whether the loss of this ability also influences the development of the disease. – INSTITUTE OF COMPLE X SYSTEMS –
… or power-to-X is the title of one of a total of four Kopernikus projects related to the transformation of the German energy sector (Energiewende). It is concerned with the storage and use of electrical energy from renewable energy sources, for example by means of transforming it into chemical energy carriers, liquid fuels, or basic chemicals for the chemical industry. The large-scale project brings together science, industry, energy suppliers, and citizens’ associations in order to find storage solutions over the next ten years that can be implemented on a large scale. – I N S T I T U T E O F E N E R GY A N D C L I M AT E R E S E A R C H –
E RC GR ANT AWARDE D
STORING RESE ARCH DATA
MILLIONS FOR QUBITS
Jülich researcher Dr. Wolfgang oyer has been awarded a ConH solidator Grant by the European Research Council (ERC). In his BETACONTROL project, he develops special molecules to treat widespread diseases such as Alzheimer’s, Parkinson’s, and type 2 diabetes mellitus. For this purpose, the ERC will provide him with around € 2 million in funding over the next five years.
The Helmholtz Data Federation, which is currently being developed, is a new, internationally interconnected infrastructure for research data. It permits scientific data to be stored in the long term and makes them accessible to the scientific community and society. So far, six research centres are members of the platform. Jülich is initially supporting projects in the fields of brain and plant research.
A new project entitled Scalable Solid State Quantum Computing is set to develop new systems for future quantum computers. These should have several hundred information units, called “qubits”, at their disposal. Current approaches are intended for systems with a maximum of ten qubits. The Helmholtz Association is providing € 6 million in funding for the project.
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Slow and steady wins the race “Rome wasn’t built in a day,” they say. Nevertheless, society tends to expect dramatic progress from science. But research takes time, especially when it’s about the climate, our health, or pitch – a tar-like substance involved in a very special long-term experiment. Research requires patience, as a multitude of examples throughout the world show.
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he first drop fell after eight years of waiting, in December 1938 – just before the start of World War II. When the second drop fell from its funnel into the beaker underneath in 1947, the devastating war was already over. This is how slowly the extremely viscous lump of pitch flows in Thomas Parnell’s experimental setup. The experiment is viewed as a prime example of long-term experiments – and it is still going! Nine drops have fallen so far. Pitch is derived from coal or resinous wood. In the Middle Ages, warm, soft pitch was used to caulk ships and barrels, or to make torches. When cool, the black substance can be shattered with a hammer like a ceramic. And yet, pitch is not a solid but behaves like a liquid at room temperature. This is what Thomas Parnell, professor of physics at the University of Queensland in Brisbane, Australia, sought to prove with his experiment: in 1927, he poured heated pitch into a funnel and then let it settle for three years. He then opened the funnel – and the wait began. Parnell only lived to see the first two drops, as he died in 1948. But the experiment continues
to this day. In 1984 – between the sixth and the seventh drop – a journal article was published about it: two scientists calculated that the pitch is 230 billion times more viscous that water, and two million times as viscous as honey. Another ten years later – as the eighth drop was looming in Australia – another long-term project was launched more than 16,000 km away in Jülich. The MOZAIC project was planned for just three years initially, however. “In 1994, I wouldn’t have dreamed that I would still be conducting this research and collecting data every day,” says Jülich climate researcher Dr. Herman Smit, who was there for the launch of the experiment. MOZAIC is short for “Measurement of Ozone and Water Vapour by Airbus In-Service Aircraft”. This long title quite accurately describes what the project is about: the measurement of ozone and water vapour – two climate-relevant gases – during the normal flight operation of Airbus aircraft. The hypothesis at the time was that flight operation was the cause of a quarter of the climate- damaging ozone at an altitude of 9–12 km.
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At least, this was the result of some computer models which scientists used in the early 1990s to predict the climate. Scientists from the French research organization CNRS (Centre nationale de la recherche scientifique) wanted to find out to what extent these models correspond to reality – a question that is also of interest for European aircraft manufacturers and airlines. The researchers’ idea was to place completely automatic measuring instruments on board commercial airliners. The instruments would thus travel for free and collect large volumes of data about the composition of the atmosphere. The experiment started soon after: funded by the EU, five airplanes operated by four European airlines took off equipped with instruments for measuring ozone and water vapour. Some of these on-board devices were developed by Jülich researchers. They are viewed as the best in the world when it comes to measuring atmospheric water vapour. And MOZAIC’s mission? To collect as much data as possible. In contrast to the pitch drop experiment, the researchers didn’t have to wait years for a measurement, although only a multitude of data – a shower of “drops”, so to speak – results in a clear image. It was therefore a case of the more data, the better.
The fact that it isn’t a lways a bad thing to travel at snail’s pace is proven by snails themselves. Although they move about very slowly, they are real sprinters in evolutionary terms: snails can adapt to new conditions within only a few decades.
» In 1994, I wouldn’t have dreamed that I would still be conducting this research and collecting data every day. « Climate researcher Dr. Herman Smit
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Also slow: continental drift
Mighty flotsam If the surface of our Earth still had the same shape it did millions of years ago, then we’d be able to tour the world by car. Because it’s in constant motion, however, the supercontinent Pangaea broke up more than 200 million years ago. The Earth’s outer crust is only a thin layer of rock floating on the mantle. But this doesn’t mean that cartographers are constantly busy correcting their maps: continental drift is extremely slow. The distance between Europe and America has only expanded by roughly 13 metres since Columbus’ discovery of the New World in 1492. The two continents move away from each other by only about two to three centimetres every year.
Also taking place in 1994, at Jülich, the go-ahead was given for another project that would last for years to come. For the first time ever, nuclear chemist Hans-Jürgen Wester produced 18F-fluoro ethyl tyrosine (FET), an amino acid artificially labelled with fluorine-18, for his doctoral research. The chemical substance had the potential to become useful in making metabolic processes in the body visible. It is closely related to the body’s own natural amino acids. Therefore, the body can absorb it through its own metabolism. And FET contains a radioactive fluorine atom.
World Record: According to the Guinness World Records, the pitch d ripping from this funnel constitutes the longest-running laboratory experiment in the world. Only nine pitch drops have fallen since 1927.
Such radioactively labelled molecules can be made visible by means of positron emission tomography (PET): this technology shows where in the body the molecules are currently located and can thus reveal tumour tissue, for example. Wester and his colleagues were initially unable to predict to what extent FET would actually be usable as a molecular spy – a radiotracer. They would first have to extensively test the molecule – counting in “pitch drop time”, this was expected to take one or two drops. In fact, laboratory experiments with tumour cells as well as with rats and mice raised hopes during the subsequent years that FET could reveal brain tumours in humans.
Meanwhile in Australia, Parnell’s successor and experiment supervisor John Mainstone was having no luck: the physicist had never seen a drop fall although he had been in charge of the experiment for almost forty years. He was getting a coffee while one fell, and another fell while he was participating in a conference. He therefore decided to install a webcam before the expected eighth drop – but when the moment arrived in November 2000, the camera failed.
FROM LAB TO CLINIC During this time, two “drops” fell almost simultaneously in the FET project. The first “drop”: at the turn of the millennium, the amino acid achieved the step from the laboratory into the clinical trial phase – initially at the Technical University of Munich, where Hans-Jürgen Wester took up work after his doctorate. But together with partner universities, a Jülich team headed by medical scientist Prof. Karl-Josef Langen also began conducting various FET PET studies Langen knew that many years of research still lay ahead for the scientists: “It is completely normal for the clinical trial of a radiotracer to take so long.” It must be verified that the new substance is safe and efficient. For this purpose, the medical
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scientists had to find as many suitable participants for their study as possible. It is thanks to Dr. Kurt Hamacher and Prof. Heinz Coenen that a second “drop” immediately followed the first one in the FET project: the two Jülich nuclear chemists succeeded in improving the production of the FET amino acid, significantly increasing the amount of FET synthesized. This is important since radioactive fluorine-18 decays so quickly that 110 minutes after its production, only half of the original amount is left. With the improved synthesis process, sufficient FET is left for the examination of several patients, even after transport to a hospital near by. It is not unusual for research to take several years before finding the optimal synthesis process for a radiotracer, according to Prof. Bernd Neumaier, who currently heads the Nuclear Chemistry subinstitute, “although the process can be accelerated these days, thanks to increased knowledge and improved equipment.” While in Australia the eighth drop fell unobserved and Jülich’s FET PET researchers achieved
» It is completely normal for the clinical trial of a radiotracer to take so long. « Medical scientist Prof. Karl-Josef Langen
substantial advances, the measuring instruments on board commercial aircraft had now spent more than 130,000 hours in flight. “What we had suspected turned out to be true: An enormous amount of data, collected over a long period of time, paint a different picture of the atmosphere than the previously conducted, isolated measuring campaigns using research aircraft or balloons,” says atmospheric researcher Smit. The findings revealed how the air at altitudes of 9–12 km contains supercooled water vapour
Also slow: Organ2/ASLSP
Longplay score In 1985, composer John Cage wrote a piece entitled “Organ2/ASLSP”. The abbreviation is short for “as slow as possible” – which is how Cage wanted the eight-page score to be played. Some Cage enthusiasts took this r equest very serious: They had a special o rgan built for the piece and installed it in the Church of St Burchard in Halberstadt. The great day dawned in 2001: the performance began – and unless anything unexpected happens, it won’t end until the year 2640. Just in case there’s a power blackout, the organ is equipped with an emergency power generator. Further information on the project: www.aslsp.org
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much more often than previously assumed. The water contained in this vapour is gaseous although droplets or ice crystals – and therefore clouds – should form due to the low temperature. Thus, some of the climate researchers’ models clearly had to be corrected. Evidently, in some regions of the world, climate-relevant clouds don’t form until reaching a moisture content which is larger than previous conventional assumptions. During flights, measuring probes in the fuselage of passenger aircraft collect data on ozone, water vapour, and carbon monoxide, for example
MORE EQUIPMENT ON THE AIRCRAFT New findings were also revealed about ozone: the data suggest that ozone at flight altitudes originates mainly from lower layers of air. In order to verify this theory – and to further complete the analysis of the atmosphere – the researchers required further, and in particular, different “drops”, i.e. data, including those of other greenhouse gases. From the year 2000 onwards, therefore, they prepared the airplanes’ equipment with measuring instruments for carbon monoxide and nitrogen oxide, the latter of which they developed themselves.
Three years later – with a long time to go before the ninth drop actually fell – the Australian pitch drop experiment in Brisbane was included in the Guinness World Records as the longest-running laboratory experiment in the world. In 2005, John Mainstone and, posthumously, Thomas Parnell received the Ig Nobel Prize, which is awarded for “improbable research” that “first makes people laugh, and then makes them think”, as the organizers put it. Meanwhile, climate research and the MOZAIC airplanes were looking forward to the next few “drops”: in 2006, MOZAIC was expanded. The EU granted the scientists funding to work out a concept for the project’s expansion and long-term financing. The MOZAIC researchers wanted to include even more airlines and also equip the airplanes with measuring instruments for aerosols and clouds as well as the greenhouse gases CO2 and methane.
Also slow: human beings
Learn first, then grow It seems it can never happen fast enough: children a lways want to grow up as fast as possible. But this takes time – much longer than it does for our closest relatives, chimpanzees, for example. They grow in height early on, while humans have to wait until puberty before a real growth spurt. Coincidence? No, it seems to be a result of evolution. In humans, it is the brain that develops before the body. If children grew as quickly as chimpanzees right from the start, they would need about 44 % more energy to supply their body with what it needs – i.e. food that the parents have to provide. This was calculated by Michael Gurven from the University of California and Robert Walker from the University of New Mexico. In a society of hunter-gatherers, it was thus more worthwhile to first “feed the brain” – b ecoming intelligent first, then growing substantially and b ecoming a smart hunter oneself.
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Also slow: whisky
Aroma develops over time Have you ever tried freshly distilled whisky? If so, you will instinctively know why it must be matured in wooden barrels for years before it’s sold. The distillate has a tangy, metallic taste – simply unpalatable. It’s the wooden barrel that extracts the unpleasant aromas from the whisky. This subtractive ageing is complemented by additive ageing: the cask not only removes flavours, it also adds some. Over time, the whisky absorbs flavours from the cask such as vanilla, caramel, or smoke. These are some of the factors that contribute to the desired flavour being achieved over the years. A good single malt whisky, for example, matures over 12–21 years. The longer it’s given time to mature, the better it becomes.
Just three years earlier, the project had faced cancellation. The EU had decided to only fund scientific projects that were concerned with new research issues. This slowed down the research for a short time, “but then the people responsible within the EU recognized that research takes time. For example, only long-term observations of the environment enable us to distinguish between short-term fluctuations and long-term trends,” says Jülich atmospheric researcher Dr. Andreas Petzold. In 2011, the European research infrastructure project IAGOS (In-Service Aircraft for a Global Observing System) was launched as the successor of MOZAIC. Jülich scientists are coordinating the project. The costs for the infrastructure, which is planned for the long term, are shared by Germany, France, and the UK. This means that the scientists can now observe the atmospheric “drops” unhindered: “We no longer have to always worry about follow-up funding, the applications for which are very time-consuming,” says Petzold, head of the Jülich IAGOS team. Three years later, in 2014, the ninth pitch drop fell in Australia – this time recorded by no fewer than three webcams for good measure. Sadly, John Mainstone did not live to see it: he died the year before.
After twenty years of research, a particularly fat “drop” also fell for FET that year: it was approved for clinical application in Switzerland. More than 150 studies involving over 12,000 patients had shown that the FET PET method is better suited for distinguishing brain tumours from surrounding tissue than other methods. However, German statutory insurance schemes will probably never pay for this kind of examination: “In order for them to do so, we would have to verify not only that FET PET is very well suited for diagnostic purposes,” says Langen, “but also that using it prolongs the life of terminally ill patients. Such studies are complicated and expensive.” But the researchers won’t let that discourage them. There are other ways of using FET PET: for example, after an operation or radiochemo therapy, newly developed tumours can be distinguished from changes in the brain arising from the pretreatment. “In any case, we make use of the experience we gained in developing FET PET in order to develop other innovative PET diagnostic methods,” nuclear chemist Neumaier and medical scientist Langen say unanimously. Meanwhile, “drops” continue to be observed in atmospheric research using IAGOS. More and more instruments, airplanes, and airlines will in future contribute to making predictions on
Recognizing risks: The FET PET d iagnostic method provides helpful information on brain t umours. For this purpose, metabolic activities are made visible (red and yellow colours).
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climate change more accurate and to examine measures for keeping the air clean. “The long-standing funding for our research and our persistence is already paying off,” says Petzold. He refers to the more than 200 scientific publications which were based on these flight data. “These data were also incorporated in the reports published by the Intergovernmental Panel on Climate Change, IPCC.” Among other things, IAGOS researchers have shown that the temperatures at altitudes of 9–12 km have not changed in the past twenty years, in spite of climate change.
from the research object itself – for example the extremely slow-dripping pitch or long-term climate change – to social as well as financial barriers. It is often not possible to predict beforehand how much time will be required. It is also not always possible to know whether the research conducted will in the end benefit society. We can be assured of one thing however: it may be worthwhile to watch the live feed of the pitch drop experiment in 2027 (online at www. thetenthwatch.com). That is when the next drop is expected to fall.
These examples show that the speed of scientific progress depends on many factors. They range
MAIN TE X T AND INTERVIE W: FR ANK FRICK EX AMPLE TEXTS: SEITENPLAN
» Progress happens at snail’s pace «
Also slow: crude oil
Sediments under pressure Oil has been the fuel of progress and industrialization for a century and a half. It develops from dead plankton, which sinks to the bottom of the sea. If the sea is deep enough, then there is no oxygen available that would decompose the remains of these small animals and plants. Instead, a sludge called sapropel forms, which is covered by sand and other sediments over time. Over the course of millions of years, this layer becomes thicker and thicker, increasing in pressure and temperature. The transformation begins – and takes 10,000 to several million years.
Three questions for Wolfgang Hess, who was the editor of scientific journal bild der wissenschaft from 1994 to 2016. For 37 years, he has been observing and describing the progress made by science and technology. What do you think about the speed of scientific progress? Let me put it this way: scientific progress often happens at snail’s pace. But even a snail covers a surprising distance over several days. It’s clear that the grand challenges facing society can be better tackled by means of research – but that doesn’t just work at the push of a button.
But doesn’t society expect fast solutions to these problems? Yes, that seems to be characteristic of our age. This puts the scientists in an increasingly difficult position: in order for them to receive funding for their research, they have to aim
high. But in doing so, they raise new expectations which they are unable to fulfil in the end.
Could you give us an example of expectations being disappointed in this way? We have yet to come to grips with diseases such as cancer, Parkinson’s, or virus infections – despite a number of medical scientists and future researchers promising to do so for decades, encouraged to no small extent by the media. The “revolution in materials research” that is often aspired to also usually turns out to be wishful thinking.
RESEARCH
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Two souls, alas!, reside within his breast In private, he is rather withdrawn – as the coordinator of a conference expecting 12,000 participants, however, he is completely in his element. Dr.-Ing. Bernd Mohr is the first non-American to organize the world’s most important conference for supercomputing.
Worth keeping an eye on: the journal HPCwire i ncluded Bernd Mohr on its list of “People to Watch 2017”.
As a young man, things were a bit different: “I was tall and lanky, a bag of bones and a computer geek, certainly no hit with the ladies,” says Bernd Mohr with a resounding laugh. A dimple appears on his cheek, and deep laughter lines around his brown eyes. It’s almost unimaginable that this giant of a man used to be shy. After all, Mohr will be opening the SC17 conference in Denver this November, the most important conference for high-performance computing (HPC). With 12,000 participants from over 60 n ations, it is the community’s largest meeting. Mohr holds all the threads, and he fully enjoys the responsibility. “It’s a kind of managerial training,” he says and laughs again. Over a period of three years – riddled with sleepless nights, countless meetings, and negotiations in the US – the 57-year-old has been organizing the conference together with 600 volunteers. “A roller-coaster ride that I would
take up again in a heartbeat,” he concludes already. Mohr is the first non-American in the 29-year history of the conference to take on this role.
COMPUTERS, NOT BRIDGES Growing up in modest circumstances in a northern Bavarian village, this typesetter’s son initially had completely different plans for his future: he wanted to build dams and bridges. But then came the open day at the University of Erlangen. “That’s where I first saw these huge computers. I was thrilled and immediately enrolled in computer science,” Mohr reminisces. The fascination still endures: “In a job creating things with my hands, I would always be restricted, for example by the material. With computer programs, in contrast, I am free. I create something new, and if it doesn’t work, I just press the delete button and start again.”
As a young computer scientist, he initially found it hard to speak about his work in front of people: “I would have preferred to conduct my research behind closed doors.” But at some point during all the talks he held in English around the globe, he shook off his reluctance – at least in the face of a large audience. The down-to-earth giant is even excited about his 10-minute opening address in front of 3,000 people. The technical requirements including floodlights and live transmission are already in place: “After all, I want to deliver a great show!” On the flight back home, however, the person sitting next to him will not hear much from him: “In private, I prefer secluding myself.” K ATJ A L Ü E R S
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RESEARCH
Highly flexible Red blood cells are very elastic and can assume various shapes in blood flows. Factors such as the speed at which they move through the veins are decisive. The faster they flow, the more they deform. And if conditions are cramped, they can bend.
No deformation
Strong deformation
Slight deformation
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Always in good shape They wriggle, roll, and glide; sometimes they even line up in an orderly fashion. Red blood cells are flexible in the way they transport oxygen from our lungs into the furthest corners of the body. Their shapes and capabilities fascinate Jülich physicist Prof. Gerhard Gompper.
Our blood vessels are often a bit like an overcrowded water slide at a swimming pool, with the red blood cells slap-bang in the middle. They look similar to rubber rings with a soft sitting area in the middle instead of a hole. Thanks to their elasticity, they worm through the smallest blood vessels and rush through the heart unscathed. Whenever it gets too cramped, the red blood cells deform, ranging from slightly bent to rolled-up ellipses or pyramids, which are reminiscent of Smurf hats. Some of these shapes were only discovered by means of computer simulations conducted by Gompper, director at the Institute of Complex Systems (ICS), and his team.
Getting the blood flowing: in reality, considerably more red and white blood cells flow through our veins. About half of our blood consists of blood cells and blood platelets, while the rest is made up mostly of water.
This diversity of shapes had remained undiscovered by microscopes: in their experiments, life scientists had selected much too viscous substances for the liquid part of the blood which surrounds the blood cells. For the blood cells, this was akin to swimming through honey instead of the more watery blood. They were therefore not able to deform as much. “Only when the biologists recreated the natural conditions in the experiments were they able to see the diversity of shapes first calculated by us,” explains Dr. Dmitry A. Fedosov, a member of Gerhard Gompper’s team.
ELASTICITY MEANS HEALTH The blood cells’ stability, on the one hand, and their e lasticity, on the other hand, is down to a mesh of protein fibres. It reinforces the double-walled membrane which envelops the blood cells. The Jülich scientists can precisely calculate the properties of this mesh and therefore learn how blood cells deform. They behave similarly to a rubber ring which happens to end up close to the edge and is compressed. On their slide through blood vessels, blood cells are bent and sometimes – if it gets even more cramped – they are even rolled or folded by the current. Where the vessels widen, the blood cells quickly revert back to their original shape.
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The simulations also permit predictions of what conditions would cause cells of a similar size – for example tumour cells – to reach the vessel walls. This aspect helps the researchers understand how metastases spread in the body and where they settle.
RECOGNIZING MALARIA
Prof. Gerhard Gompper heads Theoretical Soft Matter and B iophysics at the Institute of C omplex Systems (ICS).
Dr. Dmitry A. Fedosov has been heading his own young investigators group at ICS for five years, investigating blood flows.
This flexibility is important: diabetes, for example, causes the blood cells to stiffen. If they become less elastic, they no longer fit through the tightest blood vessels, the capillaries. This particularly concerns the hands and feet. The patients often suffer from a lack of blood circulation, which can even cause tissue to die. In the next step, the Jülich researchers calculated many thousands of cells in a current. “We’re interested in the collective behaviour,” says Gompper. “Why do many blood cells together move completely differently in a current than an individual one would? For example, they change their motion from a kind of free rolling into one that sees them orderly gliding and lining up. This knowledge is tremendously important, for example in the design of stents. These are wire-mesh tubes which keep blood vessels open after a heart attack. It also plays a role in the development of blood pumps which are implanted in the body,” he stresses. Complex model calculations conducted with the aid of supercomputers accelerate their development. Thus, physicists virtually chase thousands of red blood cells through a computer: through narrow or wide obstacle courses, at higher or lower speeds, or they vary the mobility of the blood cells or the properties of the surrounding liquid. The researchers calculate, for example, what cell concentrations can cause dangerous jams in our blood vessels, and therefore thromboses or strokes. The experts also simulate the behaviour of white blood cells. These cells, which tend to be spherical, fight pathogens. The little balls drift through our blood vessels and continuously scan the vessel walls in order to detect signals indicating an infection. But this only works if the blood flows at a certain speed. The Jülich researchers discovered that if it flows too fast or too slowly, the white blood cells don’t reach the outer edges of the blood vessels, instead being held in the centre of the current by the red blood cells.
“Our calculation models can be used to develop new technologies, for example for diagnostic purposes,” explains Dmitry Fedosov. A diagnosis system for blood samples is conceivable, in order to detect pathogens such as the malaria pathogen. Malaria is caused by parasites infecting the red blood cells. “However, in some cases, only very small numbers of pathogens are present in the blood at certain periods during the infection. This makes it difficult to determine whether someone is actually infected,” stresses Gompper. What is needed, therefore, is an idea permitting as many infected blood cells as possible to be collected for a sample. The researchers’ approach is a kind of tiny sorting mechanism through which a blood sample can be conducted. The clever design of the mechanism consisting of microtubes would sort the parasite-loaded blood cells from the blood, increasing their concentration. “This works because the affected blood cells have different flow properties,” says Gompper. “We’re testing and optimizing the device using simulations on supercomputers.” Such a diagnostic system is not yet available on the market. The results from Jülich about the variety of shapes and also the complex flow behaviour of blood cells have, however, laid the foundation for its development. B R I G I T T E S TA H L - B U S S E
Constituents of our blood
45 %
55 %
Blood cells red blood cells (erythrocytes) white blood cells (leukocyctes) blood platelets (thrombocytes)
Blood plasma water (90 %) proteins nutrients salts metabolic products enzymes hormones
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What does an axion weigh? Space – so many questions left unanswered. But there is one particle that could provide some answers: the axion. It has not yet been discovered, but researchers have come a little closer to finding out its properties.
An inventory of the universe reveals a set of astonishing facts: only around 5 % of it is ordinary matter, half of which makes up stars, and the other half planets. A further 27 % remains completely invisible, representing what is called dark matter. Its effects on galaxies have been verified by researchers, but we still don’t know what it’s made up of. The remainder of the cosmic inventory is even more exotic: around 68 % of the universe consists of the as yet unknown “dark energy”. It causes our cosmos to expand at ever increasing speed.
4.9 % ordinary matter
26.8 % dark matter
68.3 % dark energy
While researchers know little about the nature of dark energy, they have some concrete theories concerning dark matter: one candidate for making up the invisible quarter of the universe is the axion, an elementary particle. Countless billions of axions would have to exist in the cosmos. But so far, researchers have yet to detect even one of them. The search is made even more complicated by the fact that little is yet known about the properties of axions. It is assumed to be very light, between a billion and a trillion times lighter than an electron. Just how large this difference is becomes clear when considering everyday units: there is, after all, a huge difference between whether something weighs a gram or a kilogram.
Matter and energy distribution in the universe
“It would have taken us a hundred million years to calculate this – but we didn’t want to wait quite that long.”
A team headed by Prof. Kalman Szabo from the Jülich Supercomputing Centre and Prof. Zoltan Fodor from the University of Wuppertal recently succeeded in determining the mass of the axion more precisely. Using elaborate calculations on Jülich’s supercomputer JUQUEEN, the researchers simulated the very early universe – under the assumption that axions make up the main constituent of dark matter.
“Using previously known methods, it would have taken us a hundred million years to calculate this – but we didn’t want to wait quite that long,” says Fodor. The team of researchers therefore developed new mathematical methods to describe the processes just after the Big Bang. And successfully: instead of a hundred million years, the simulations took two years in the end – a normal PC would have taken about ten thousand years. Szabo explains the result: “If the axion exists, then its weight range is thirty times smaller than previously assumed.” Scaled down to everyday units: the candidate weighs between one and 30 grams. According to the Jülich scientist, “the result helps plan new experiments to find the axion in a more focused way – and maybe solve the mystery of dark matter.” JENS KUBE
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RESEARCH
Trip to the underworld As part of a project entitled ORPHEUS, practitioners and theorists are developing optimal fire-protection and evacuation concepts for underground train stations.
It’s Germany’s oldest underground system: when the first train was operated in Berlin in 1902, fire protection was viewed as a minor matter. These days, strict safety requirements apply to Germany’s largest underground rapid transit system. And yet, there is constant need for improvement: “Safety technology is advancing continuously. New insights must be taken into consideration – for existing stations as well as those being built,” says Lukas Arnold from the Jülich Supercomputing Centre (JSC). He coordinates the ORPHEUS collaborative project, which was launched in 2015. It uses experiments and simulations to optimize smoke and personnel removal in underground stations in case of fire. Safety and event technicians, mathematicians, geographers, civil engineers, communications scientists, psychologists, physicists, and emergency service providers are working side by side in order to improve fire protection together. Ultimately, it will be the passengers who benefit: if there is a fire, the evacuation procedure will be optimal, using the fastest and safest escape route.
Especially in the case of fires, it is important to leave the location affected as fast as possible. What is particularly dangerous is the smoke, since it contains highly toxic substances and impedes visibility as well as orientation. But how smoke develops in each underground station cannot generally be predicted, due to the complex design of the buildings, with several levels, low ceilings, and air streams that vary with the seasons and the weather. “If there is a fire in a residential or commercial building, the smoke will be drawn upwards, and people will escape downwards. If there is a fire in an underground station, the smoke will generally still move upwards, but that is also the direction in which people will try to escape. The pathways taken by smoke and people are thus identical, which exacerbates the situation,” explains Arnold.
HEAT AND ARTIFICIAL SMOKE “ORPHEUS is concerned with both passive and active fire protection – the latter being the case when the fire brigade is
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Into the smoke: the fire brigade used the fire experiment in the Berlin underground as a t raining exercise.
“The pathways taken by smoke and people are identical, which exacerbates the situation.” called.” The project experiments are all conducted in the Berlin underground station Osloer Straße. Burners controlled via computers produce heat, and in order to measure the air flow, a harmless gas mixture is used. Of course, artificial smoke is also required. The advantage of the subterranean “live-and-incolour” experiments is that the scientists can later track the experiments with their models and thus verify whether the data from the experiment correspond to those from the calculation. At the same time, the results form the basis for simulations and
physical models of a smaller scale, which the researchers use to predict how smoke spreads and what technical measures can be used in a meaningful way. “The entire work of the ORPHEUS project pursues the aim of making general statements on the fire protection of underground traffic facilities,” says the Jülich expert. In addition to coordinating the project, his team is mainly responsible for developing numerical models. This means that the researchers spend countless hours in front of the computer in order to improve or newly develop algorithms. Current fire protection measures also make use of simulations which calculate how much time pedestrians need in order to leave a building. Other simulations estimate how much time the p edestrians actually have for their escape. “We’re now developing the first models combining both worlds while taking into consideration the multitude of fire scenarios,” says Arnold.
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Another aspect the Jülich scientists are focusing on is trying to predict in real time how smoke develops. “If you tried to calculate this for our Berlin underground station today, it would take weeks for actual results. We want to develop a predictive real-time model using simplified models and special computer hardware. Where does the smoke spread? What areas will probably stay free of smoke? Using this information, we want to prepare the numerical fundamentals for tools which can then help rescuers decide what to do,” explains project coordinator Arnold.
Physicist Lukas Arnold from the Jülich Supercomputing Centre keeps it cool: he coordinates the ORPHEUS project.
CHOOSING THE RIGHT-SIZE CUBES In order to produce results quickly, the Jülich researchers use an “adaptive computational mesh”. “Simulating a fire using conventional software is performed by dividing the space into equal cubes,” says Arnold. The smaller the cubes, the more detailed the resolution, but the longer it takes the computer for the calculation. “For example, if we halve the edge length of the cubes, the computation time increases by a factor of 16, meaning the calculation takes not one day but sixteen. So the engineers always have to find a balance between what they want and what can be calculated on a daily basis,” explains the physicist. The adaptive-mesh methods are much more flexible: using them, it is possible to individually adapt the size of the cubes to the fire situation. At the actual location of the fire, where a high spatial resolution is needed, the cubes are as small as possible. The longer computation time required to do so is provided by the areas of the building that are not affected. These are depicted with less precision, i.e. larger cubes. “To put it simply: if there is a fire downstairs in the train, I will probably not need the same mesh for the snack stall on the
intermediate level because it is probably not relevant to the spreading of the smoke. It is these adaptive-mesh methods that we develop,” says the JSC scientist. As a theoretical physicist, he is fascinated mainly by the complexity of fire dynamics investigated in ORPHEUS: “Many effects cannot even be considered in isolation, but only as a whole. This range of physical and chemical effects is intriguing.” And he also likes the collaboration with many different people from various areas: “Whether it’s smoke or crisis management, evacuation, simulations, or experiments – everyone has different talents. Together, we make a great team to improve fire protection!” K ATJ A L Ü E R S
Flaming spectacle: using propane burners and fog m achines, the project partners conducted experiments in the Berlin underground to simulate how smoke spreads in case of fire.
In future, computer simulations produced by the Jülich researchers are set to predict in real time how and where smoke spreads.
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What’s your research all about, Prof. Rother? Junior professor at RWTH Aachen University and head of a Helmholtz Young Investigators Group at the Institute of Bio- and Geosciences – Biotechnology
“I fabricate building blocks for medications – in an environmentally friendly way, using little energy and without producing toxic waste. My team and I have developed a sort of toolbox containing various different enzymes for this purpose. Using these biocatalysts, we build up the molecules of the active substances step by step. Each manufacturing phase requires a tailor-made enzyme. We thus have to select the correct enzymes – or change them in a targeted manner – and then combine them in clever ways. Together with partners from industry, we then transform our laboratory results into efficient production processes.”
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RESEARCH
Chewing the cud Germany has a problem: too much nitrate in the groundwater. This is primarily caused by liquid manure and mineral fertilizer, of which an excess amount ends up on fields. JĂźlich researchers are investigating where and how the use of nitrate can be reduced.
What goes in must come out: according to agricultural Âh istorians, animal excrements have been used as fertilizer for more than 8,000 years.
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Germany’s groundwater is not in a good state: the German Federal Government reported in January 2017 that almost a third of the 740 measuring points exhibited exceeding levels of nitrate between 2012 and 2014. In other words: a quarter of Germany’s 990 groundwater bodies – distinct volumes of groundwater – are polluted. There are also problems associated with surface waters and coastal regions: the elevated nitrate values contribute to certain aquatic plants reproducing too prolifically, particularly algae. As a consequence of rotting algae and increased putrefaction processes, the water is depleted of oxygen, endangering the fundamental existence of fish and other animals. The body of water concerned becomes polluted and “dies” in effect. Jülich researchers headed by Frank Wendland from the Institute of Bio- and Geosciences (IBG-3) want to take a closer look. Using computer models they developed themselves, they are investigating how much the pollution of groundwater and surface and coastal waters varies – and how the nitrates get there. “In most cases, the high nitrate contents originate from the overfertilization of fields with liquid manure and mineral fertilizer,” says Wendland. Using the models, the scientists calculate by how much the nitrate loadings in d ifferent regions would have to be decreased in order to comply with the EU upper limit. Many federal states provide Jülich’s researchers with special data for this purpose, for example on land use, soil properties, climate conditions, and the groundwater.
Charged by EC From the European Commission’s point of view, Germany has failed to take stricter action against nitrate pollution in the groundwater. According to the EU Nitrates Directive, the Federal Republic has a legal obligation to do so. This is why the European Commission has referred Germany to the European Court of Justice. Other countries have also been charged. France has already been condemned, with the pos sibility of paying a fine of up to € 3 billion. In February 2017, the German Bundestag adopted a revision of the German reg ulation on fertilizers. The Federal Government hopes that with this revision in place, the nitrate pollution can be decreased and the European Commission’s charge thus abated. (As of March 2017)
Around 200 million tonnes of manure end up on German fields every year.
REGIONAL DIFFERENCES Hotspots with particularly elevated pollution levels can be identified comparatively easily. “Developing measures to reduce elevated nitrate values, in contrast, is more difficult,” says the water expert. Local differences must be considered, for example when it comes to groundwater: low levels of fertilization do not automatically mean less nitrate pollution. Thus, the nitrate value in regions with little rainfall, such as the Zülpich plain between Aachen and Cologne, tend to exceed the limit value quite quickly – even when farmers strictly adhere to the limitations of the regulation on fertilizers. The reason for this is that the nitrate entering the groundwater is diluted to a lesser extent than in water-rich regions. In northern North Rhine-Westphalia (NRW), nitrate pollution also plays a role in flowing waters such as streams or rivers. There, farmers began installing drainage systems in their fields many decades ago, preventing the soil from becoming too wet. Draining systems thus lead surplus water away into ditches or streams. Such constructions made it possible to use some of the area as arable farmland in the first place. The disadvantage: water from fields finds its way into surface wa-
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RESEARCH
Expert for water and nitrate pollution: Prof. Frank Wendland from the Institute of Bio- and Geosciences (IBG-3)
tions for NRW together with partners from science, agriculture, and administration. The Thünen Institute in Braunschweig and the NRW Chamber of Agriculture are developing approaches to reduce nitrate pollution caused by agriculture.
ters much faster, and with it surplus nitrate from the soil. The nitrates thus concentrate in streams and lakes much faster, polluting flowing waters and coastal regions. “In order to reduce the nitrate content, we have to consider not only water-management and hydrological aspects, but also agriculture,” says Frank Wendland. As part of the GROWA+ NRW 2021 project, the Jülich researchers are seeking solu-
At Jülich, the computer models are used to simulate whether and how these ideas can have the desired effect. “We analyse in advance which measures are best suited for which region in NRW,” emphasizes Wendland, who coordinates the scientific section of GROWA+NRW 2021. The first results of the project, which is funded by the NRW ministry of the environment, are expected to be presented in late 2017. J A N I N E VA N A C K E R E N
Difficult comparisons Germany had previously been in second to last place when it came to groundwater nitrate pollution levels in the EU – only Malta came off worse. Such comparisons are based on data which the member states report to the EU. There are, however, no uniform criteria for the measurement networks. The EU Directive simply requires selected representative monitoring points which gather data on the nitrate from agricultural sources entering the groundwater. “Germany’s bad performance is mainly due to the choice of monitoring points,” says Frank Wendland. He explains that German authorities in the mid-1990s selected around 160 groundwater monitoring points with high nitrate levels. This was meant to work par ticularly well in verifying how efficient new measures are. However, these were also the values that the EU used for comparative purposes for Germany. Ger many has since expanded its measuring network to almost 740 groundwater monitoring points, also tak ing care to spread them representatively. In this way, the quality of German groundwater has risen from the penultimate place in the EU towards the middle of the table. “But this does not change the fact that we have a nitrate problem,” stresses Wendland.
Nitrate concentration in seepage water in 2010
The nitrate concentration in North Rhine-Westphalia’s seepage water as calculated by the GROWA computer model. If the nitrate value exceeds 50 milligrams per litre, the risk of nitrate polluting the groundwater is particularly high. In NRW, this is the case in the regions where livestock farming is particularly intensive.
GROWA+NRW 2021 partner project North Rhine-Westphalian State Agency for Nature, Environment and Consumer Protection (LANUV), Institute of Bio- and Geosciences (IBG-3), Thünen Institute Braunschweig, North Rhine-Westphalian Chamber of Agriculture, Geological Survey of North Rhine-Westphalia
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30% of all running waters in Lower Saxony are polluted with pharmaceuticals, including the river Leine in Hannover.
“No legal limit values for drugs” Nitrates aren’t the only substances polluting our water. These days, rivers and lakes resemble a whole cocktail of pharmaceuticals. The GROWA software, developed at Jülich, permits this cocktail to be investigated – in addition to nitrate pollution levels. We interviewed Jülich water expert Dr. Björn Tetzlaff.
A study you conducted on behalf of the Lower Saxon State Department for Waterway, Coastal and Nature Conservation showed that the rivers around Osnabrück, Braunschweig, and Hannover are heavily polluted with pharmaceuticals. How come? A major proportion of all consumed pharmaceuticals does not remain in the body but is excreted and thus ends up in the waste water. Water treatment plants can only filter out a certain percentage, if that. Firstly, the regions
or an entire ecosystem has not yet been researched – we are breaking new ground here. It’s also not yet clear what effects the residues have on drinking water. There are therefore no legal limit values yet.
What is the next step?
mentioned have high population densities, and secondly, the rivers there don’t always carry enough water to sufficiently dilute the treated waste water. The problem is set to grow even further because the population is ageing, and with increasing age, people need more medications.
First, we have to find out what other substances are contained in the waste water. For this purpose, we are launching a follow-up project investigating not just three but 17 active substances. These will include contraceptive substances and medications against metabolic disorders. To this end, we are refining the GROWA computer model developed at Jülich, which we already used in the first project. Once we know the exact extent to which locations are polluted with which active substances, then suitable countermeasures can be developed.
What effect do the residues have? How the pharmaceutical cocktail in waste water affects individual species
I N T E R V I E W C O N D U C T E D BY J A N I N E VA N A C K E R E N
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Biophysicist Prof. Paolo Carloni models what happens in the human body on a molecular level – for example during sensory perception processes, but also in cases of neurodegenerative diseases, AIDS, or cancer.
A matter of taste Coffee? The perfect start to the day for Paolo Carloni. But not everyone likes the taste of coffee and its usually slightly bitter flavour. But this is exactly what the researcher is interested in: together with his colleagues, he investigates what happens in the human body when it tastes bitter substances – starting right at the beginning, the tongue.
espresso machine. Carloni takes two cups and places them under the machine. After the touch of a button, some bubbling noises, and a hiss, they are filled with the Italian national drink, complete with the typical golden-brown foam on top – the crema. The physicist, who was born in Florence, hands the cup to his Italo-Argentinian colleague Dr. Alejandro Giorgetti. Carloni takes a sip of his coffee, which of course he drinks without sugar or milk. He likes the slightly bitter taste of the espresso. “Coffee triggers complex reactions on our tongue, starting with the bitter taste receptors.”
At first glance, there is nothing out of the ordinary about Prof. Paolo Carloni’s office: a desk with a computer, a bookshelf, and a table and chairs. A closer look, however, reveals a small
Both scientists work at the Institute for Advanced Simulation – Computational Biomedicine, which Carloni heads. “So far, we know hardly anything about what effects bitter substances have in the
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body and how stimulus processing works in the brain. This is why we wanted to start out by investigating the structure of bitter receptors.” Using our tongue, we can distinguish five different tastes: sweet, sour, salty, bitter, and umami. The ability to taste bitterness – the most complex of all tastes – came in very handy thousands of years ago: the bitter taste of many poisonous plants prevented hunter-gatherers from eating them. Both scientists take another sip of espresso. “There are 25 different types of bitter receptors on our tongue, which are able to filter around 10,000 bitter substances from the world of taste,” says Alejandro Giorgetti, who has been studying the structure of molecules for many years. His particular field of interest is receptors on neuronal membranes such as the numerous b itter receptors on the tongue. “Just how these receptors perceive the bitter substances was unclear for a long time,” says Carloni, “but a few years ago, Wolfgang Meyerhof, genetics professor from the German Institute of Human Nutrition (DIfE), had an interesting hypothesis about bitter receptors that he wanted to examine with our help. He thought that bitter receptors may possess a kind of gate through which only certain molecules can slip. They dock to the receptors, starting the process that leads to our tasting bitterness.”
STARTING AT STRYCHNINE The researchers started out by examining a receptor which was already known to be a docking site for the highly toxic and bitter-tasting compound strychnine. “Using these data and state-of-the-art bioinformatics methods, we modelled a possible structure of the strychnine receptor and then predicted where exactly the strychnine might dock to it,” says Giorgetti. Using human cells in laboratory experiments, Meyerhof and his team then checked whether the Jülich researchers’ assumptions were correct. Meyerhof’s experiments verified the result of the simulations: the strychnine bound itself to the bitter receptor as predicted. This encouraged Carloni and his team to continue working on their model: they simulated different interactions between strychnine and the receptor using Jülich’s supercomputers. “In doing so, we discovered something unexpected: the receptor had not just one docking site, but two! The first does indeed act like a kind of gate which only
lets suitable molecules through to the second docking location. The strychnine binds itself to it, triggering a signal that is transmitted to the brain,” explains Carloni. This access control predicted by Meyerhof could be a very efficient system for the tongue to pre-filter the multitude of different substances.
TASTE FIRST, SMELL SECOND Carloni and Giorgetti have now also decoded the three-dimensional structure of a second bitter receptor. And there’s no sign of slowing down: “We’re optimistic that we could decode the structure of all remaining bitter receptors within a year,” says Carloni. The years of working on models and simulations is paying off – they are universally applicable for studying the structure of other receptors. But the researchers don’t want to stop at the 25 different bitter receptors on the human tongue. Just recently, scientists from the Medical Center of the University of Freiburg discovered that there are also similar bitter receptors on our skin, and they have even been detected in the brain, lungs, and gut! In the latter, they presumably influence the immune system and metabolism. The structure of these receptors could also be revealed using the existing models.
Germans drink 149 litres of coffee every year on average – in contrast to only 137 litres of mineral water.
Bitter substances in coffee form particularly during the roasting and brewing of the coffee beans.
After that, Paolo Carloni and Alejandro Giorgetti want to address a different, even more complex sense: smell, and the innumerable receptors involved in that process. There’s now only a little bit of crema left in the espresso cups. “The work we conduct is basic research and its practical use may not be obvious at first glance,” says Paolo Carloni. “But I believe that it may contribute to understanding how exactly the process of tasting or smelling something works in our body. And maybe, one day, we can use these insights to produce food that tastes even better.” For example, an espresso that is even more aromatic so that more people will be able to drink it without sugar or milk like Paolo Carloni. JOCHEN STEINER
Robusta coffee contains considerably more bitter substances than Arabica coffee, the second main cultivation variety.
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Olympus for materials researchers and skiers 2.2 plus Jülich’s campus measures 2.2 km2. But Jülich scientists are active beyond the campus – for example at Institut Laue-Langevin (ILL) in Grenoble, which operates the world’s most powerful continuous neutron source.
The location German–French friendship In 1967, Germany and France founded the research centre Institut Laue- Langevin (ILL) in Grenoble. This was mainly thanks to the friendship and joint commitment shown by the French Nobel Laureate Louis Néel, professor of physics in Grenoble, and his German colleague Heinz Maier-Leibnitz. The German nuclear physicist became founding director of ILL.
Paradise for mountaineers Mountains as far as the eye can see: Grenoble is surrounded by three mountain massifs with peaks of almost 3,000 metres. Hikers, mountaineers, mountain bikers, and skiers particularly will get their money’s worth: the bottom ski lift stations can be reached from the city in under an hour.
Olympic One of the residential districts of Grenoble is called Village Olympique – but there is nothing left of the Olympic Village of the 1968 Winter Olympics. They were the first Olympic Games during which doping tests were carried out.
Grenoble is the largest city in the Alps, situated close to the highest mountain region. The rivers Isère and Drac meet here.
Why there? Dr. Karin Schmalzl works at Institut Laue-Langevin (ILL) with another Jülich researcher and an international team. What is it you do at ILL?
1,500 and more scientists come to Grenoble every year to investigate the position and motion of atoms in materials using neutrons.
I support visiting scientists who conduct neutron measurements using a spectrometer from Jülich. In addition, I use this instrument to investigate the fundamental properties of magnetic materials which are of interest for energy-efficient cooling systems.
And measuring times are highly coveted, presumably? Absolutely. To make use of the valuable time during which the neutron beam is available, I sometimes work late at night or on weekends.
Why does Jülich operate an instrument there? In order to have access to one of the world’s most powerful neutron sources. It is particularly well suited to investigating materials, for example for energy technology.
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THUMBS UP S TO R IE S F R O M DA ILY R E S E A R C H LIF E
Two new Jülich Blogs Some readers may recall Reimar Bauer from effzett issue 1-16, entitled “Python – the wonderful world of programming”. In the article, the scientist from Jülich’s Institute of Energy and Climate Research described how he programs applications for scientific exchange. In his blog entitled “Verändere die Welt, programmiere” (“Change the world, get programming”) written in German, he gives practical insights into little programs that simplify our everyday life. The second new Jülich Blog, “ DocBlog” is not dedicated to any specific area of research. In contrast, Stefanie Hamacher writes about overarching topics that matter to Jülich doctoral researchers and their organization, the “DocTeam”. – BLOGS.FZ-JUELICH.DE –
M OV E M E N T S T U DY
Dancing is art – and science What makes a woman a good dancer? This was the question posed by scientists from the UK’s Northumbria University. They recorded the outlines of 39 female dancers and had 200 test subjects evaluate them. An animation on the website of the New York Times shows what makes a dancer attractive, according to their results: wide hip swings and moving the left and right extremities in different ways, i.e. asymmetric arm and thigh movements. The scientists believe female fertility to underlie the attractiveness of these rhythmic movements. They had previously investigated the dancing styles of male dancers – the female audience paid particular attention to the upper body. – W W W. N Y T I M E S . C O M – S E A R C H T E R M : DA N C E M O V E S W O M E N H I P S
W E B V ID E O
Evolution in 24 hours If evolution is compressed into one day, modern human beings only enter the scene at just before midnight. The team from the ARD television show Planet Wissen explains in a web video how the first plant and animal species leave the ocean at close to 22:00. At 22:45, dinosaurs start ruling the world for a few minutes before being wiped out by a meteorite impact. It’s not until 23:00 that the hour of the mammals strikes. It takes another 59 minutes for the first primates to enter the stage, with homo sapiens waiting until three seconds to midnight to make a grand entrance. – W W W. P L A N E T- W I S S E N . D E – S E A R C H T E R M : E VO L U T I O N I N 2 4 S T U N D E N
RESEARCH IN A TWEET Fit for purpose – Jülich fuel cells secure emergency power supply for police radio system. #PoliceNRW #FuelCell Dr. Martin Müller and his colleagues from the Institute of Energy and Climate Research spent nine months testing whether their direct methanol fuel cells fulfil the requirements set by the police in North Rhine-Westphalia – successfully: at a radio base, they reliably delivered the required 72 hours’ worth of backup power for the digital radio system. Their task is now to develop a product ready for series production. www.fz-juelich.de/notstrom-fuer-polizei