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Mine, Mine, Mine!

A lack of impulse control prevents children from sharing fairly – even though they understand the benefits of sharing

If children do not share fairly with each other, it may not nec- er, according to researchers at the Max Planck Institute for essarily be due to a lack of insight. They understand very ear- Human Cognitive and Brain Sciences in Leipzig, it takes some ly on that fairness and generosity can be beneficial. Howev- time before they possess the neuronal requirements to act in accordance with this understanding. Researchers tested children between the ages of 6 and 13 in var- ious game situations in which the children were ex- pected to share with another child. Most of the old- er children, like adults, made fairer offers if there was a chance that their counterpart could refuse the offer. If this happened, in this particular game, both parties left empty-handed. The younger children, on the other hand, did not behave more fairly in this game, running the risk that their partner would not accept an unfair offer and they would both end up with nothing. Measurements taken with a mag- netic resonance scanner showed that the lateral pre- frontal cortex – an area of the brain that, among other things, is necessary for controlling a person’s own behavior – was less active in younger children than in older subjects. (Neuron, March 8, 2012)

Sharing fairly at elementary school age – easier said than done: A region of the brain that holds the key to behavior control develops gradually in children.

Catalyst for Cleaner Air

The atmosphere has a robust capacity to clean itself, thanks duced mainly in tropical rainforests. Until now, it was to the consistent recycling of its cleaning agents – hydrox- known only for consuming hydroxyl radicals during its yl radicals. These are generated in the atmosphere by UV chemical cleaning. This is also the case when there are high light, from water and ozone, and break down organic com- concentrations of hydroxyls in the air. At low concentra- pounds in the air. Scientists at the Max Planck Institute for tions, however, isoprene is broken down through a chem- Chemistry in Mainz have now clarified exactly how the ical mechanism in which more of the atmospheric clean- radicals are recycled. According to their findings, the reac- ing agents are produced than are removed. Isoprene thus tive molecules can be produced when isoprene is broken acts as a buffer that can diminish the increase in green- down. As a key component of essential oils, isoprene is house gases and other air pollutants. (Nature Geoscience on- emitted into the atmosphere by plants, and is thus pro- line, February 26, 2012)

OH recycling during the day (%) OH recycling at night (%) 110 80°N 80°N 100 90 40°N 40°N 80 The world maps show how 70 efficiently hydroxyl radicals 60 are recycled during the day 0°N 0°N 50 and at night. During the day, 40 they are formed mainly over forests, while at night, effi- 40°S 40°S 30 20 ciency is generally high over 10 continental regions. 80 80 °S °S 0

100° W 0° 100° E 100° W 0° 100° E Photo: MPI for Human Cognitive and Brain Sciences; graphics: Chemistry – Domenico Taraborrelli

42 MaxPlanckResearch 2 | 12 Photos: MPI for Molecular Biomedicine (top), MAGIC collaboration (bottom) Direct GeneticExchange to contact zones to contact Plants transfer the genetic material in their chloroplasts transferred chloroplasts can even be transferred chloroplastscanevenbe tosynthesis. Thegeneticmaterialinthe plasts togetherwiththeirgenesforpho- the plantscanexchangetheirchloro- Physiology inPotsdamdiscoveredthat Max PlanckInstituteofMolecularPlant naturally iftheytouch.Scientistsatthe – plantsthemselvesalsogrowtogether fruit treesandgardenplantsinthisway But itisnotonlyhumanswhoenhance od forcombiningplantcharacteristics. Grafting isapopularagriculturalmeth- lished online) ( a lowerworkingmemorycapacity. tion toatask,wecancompensate for term memory:bypayingmore atten- mercy ofthecapacityour short- However, wearenotcompletelyatthe form thetaskswithoutanyproblems. tine tasks,yetstillmanagedtoper- wander morefrequentlyduringrou- ry capacityallowedtheirmindsto who hadagreatershort-termmemo- thoughts: participantsinthestudy ty andanunhinderedstreamof the mentalworkingmemorycapaci- tests, thereisacorrelationbetween searchers determinedinmemory their mindstowander.Asthere- form routinetaskswhileallowing term memoryallowshumanstoper- and BrainSciencesinLeipzig,short- Planck InstituteforHumanCognitive According toresearchersattheMax have readimmediatelyafterwards. you willstillrecallmostofwhat briefly, againandagain.Despitethis, likely thatyourthoughtswillwander While readingthisarticle,itishighly Thoughts Wandering Psychological Science , March14,2012,pub- A naturalgraftbetweenabirch(left)andanoak.Atthepointofcontact, the twospecies,whichcannotbehybridized,canexchangegenes.

passed on to the next generation. In passed ontothenextgeneration.In (PNAS, January 30, 2012, publishedonline) 30,2012, (PNAS, January habitat andseekoutanewcell how thechloroplastsleavetheiroriginal ducing. Researchers donotyetknow can alsoexchangegeneswithoutrepro- two wildspecies.Likebacteria,plants chloroplast genomeunchangedtothe that thecultivatedspeciestransferredits cultivated species.Theiranalysesshowed ed twospeciesofwildtobaccoontoa their experiments,theresearchers graft- trum. Ifoneofthesebeamscrossesthe most theentireelectromagneticspec- field linesandemitradiationinal- particles. Theymovealongmagnetic and tenseconds,emittingcharged a periodofbetweenonemillisecond neutron starsrotateontheiraxesfor diameter ofjust20kilometers.These similar tothatoftheSun,butwitha dense spheresofneutronswithamass nants ofburnt-outstars–extremely jects inouterspace.Theyaretherem- Pulsars aresomeofthemostexoticob- Powerhouse intheCrabNebula . March 30,2012) tute ofPhysics. Mirzoyan fromtheMaxPlanckInsti- that areasyetunknown,”saysRazmik sis, theremustbeprocessesbehindthis thought possible.“Inthefinalanaly- at least50timesmorethantheorists measurable energyofupto400GeV– one millisecondwithamaximum sar emitspulseslastingapproximately to access,anddiscoveredthatthepul- a regionthatwaspreviouslydifficult from 25to400gigaelectronvolts(GeV), dle ofenergyinthegamma-rayregion thecosmicbun- lands. Theyobserved Is- scopes inLaPalmatheCanary tute ofPhysics,usingtwoMAGICtele- scientists fromtheMaxPlanckInsti- al teamofresearchers thatincluded This wasconfirmedbyaninternation- Crab Nebulaisparticularlystrong. house. Thepulsarinthecenterof ment, justlikeasignalfromlight- line ofsight,thestarflashesforamo- higher thantheoriststhoughtpossible. gigaelectronvolts (GeV)–atleast50 times gamma-ray pulsesmeasuringupto 400 Cosmic lighthouse:TheCrabPulsar emits 2 | ( 12 Astronomy & Astrophysics MaxPlanckResearch MaxPlanckResearch 43 , SPECTRUM

Fossil Planets

Astronomers discover a solar system from the universe’s early days

A glimpse into alien worlds: An artist’s impression of the HIP 11952 in the (“whale”) and its two Jupiter-like planets. The two celestial bodies orbit their parent star in 7 and 290 days.

came into existence just one billion after the Big Bang. “The planets probably formed when our itself was still a baby,” says Johny Setiawan from the Max Planck Institute for Astronomy. Conse- quently, the star contains essentially only hydrogen and helium, which were by far the most abundant elements in the early universe. All heavy elements – which as- tronomers call “metals” – were produced only over the course of billions of years in- side , and then flung into space as su- pernova explosions. This, in turn, should favor the formation of planets, since, ac- cording to traditional models, planets emerge in metal-rich clouds around stars. This means that the formation of planets around metal-poor stars should be an ex- tremely rare occurrence. However, astron- The discovery of planets that orbit distant is part and omers discovered another solar system of a similar age just parcel of everyday astronomical life. So the discovery of the two years ago. They conclude from this that new planets are new system around HIP 11952, a star with two planets locat- obviously formed during all periods of cosmic history. Why ed some 375 light-years away, is itself nothing special. How- and how? The researchers want to conduct further observa- ever, HIP 11952 is 12.8 billion years old – in other words, it tions to find out. (Astronomy & Astrophysics, March 5, 2012)

Molecules as Radio Stations

Radio communication is now possible at an elemental lev- el: Scientists at the ETH Zurich and the Max Planck Institute for the Science of Light in Erlangen used two molecules as antennas and transmitted signals between them in the form of individual photons, or light particles. Since a single pho- ton usually interacts very little with a molecule, the scien- tists had to use some experimental tricks to ensure that the recipient molecule registered the light signal. This includ- ed, for example, directing the transmitted photon to the re- cipient molecule using powerful lenses. They also matched the color of the emitted photon very closely with the color that the other molecule can receive. A radio connection communicated through individual photons would be suit- able for various applications of quantum communication, such as quantum encryption, or in a quantum computer. A transmitter molecule of the organic compound DBATT emits a stream of single photons, which are shown as wave packets. Physical Review Letters ( , February 27, 2012) The recipient molecule scatters these photons. Photos: Timotheos Samartzidis (top), Robert Lettow (bottom)

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Followers Foster Democracy

The majority attracts undecided individuals to its side

Social beings must reach decisions jointly, regardless of ity from taking control. However, the calculations also whether they live in a shoal of fish or in human society. show that the number of poorly informed individuals must In some cases, a small, resolute group may succeed in not be excessive. In such cases, the decisions follow a ran- bending the whole community to its will. The commonly dom pattern. (Science, December 16, 2011) held view is that such groups will always be successful when they are faced with many poorly informed and un- decided individuals. Using computer models and behav- ioral studies of fish, a group of researchers that included colleagues from the Max Planck Institute for the Physics of Complex Systems discovered that poorly informed in- dividuals tend to support the majority rather than a par- ticularly determined minority. The researchers based their models on just a few gen- eralized assumptions. The results thus apply to all systems in which individuals prefer to follow one another rather than engage in conflict. Applied to humans, this means that uninformed and therefore undecided individuals can facilitate a democratic outcome, as they prevent a minor-

Always following the crowd: Undecided contemporaries, too, can benefit democracy.

From Specialist Straight Sweet against Sugar to Multitalent It is used as a raw material in licorice, calms the stomach and helps alleviate respirato- Scientists at the Max Planck Insti- form only certain types of tissue, in ry diseases: licorice root. The Medicinal tute for Molecular Biomedicine in this case nerve tissue. The scientists Plant of 2012 has been cherished in tradi- Münster extracted somatic stem now want to examine whether hu- tional healing since ancient times. Re- cells from fully differentiated so- man cells behave in a similar way to searchers at the Max Planck Institute for matic cells in mice. Using a com- mouse cells. (Cell Stem Cell, April 6, 2012) Molecular Genetics in Berlin have now dis- bination of growth factors in covered that licorice root also contains which the factor Brn4 plays a key substances that have an anti-diabetic ef- role, the researchers transformed fect. The amorfrutins, as they are known, skin cells into neuronal stem cells. not only reduce blood sugar, they are also Prior to this, a detour through plu- anti-inflammatory and are very well toler- ripotent stem cells was required. ated. The health benefits are based on the These cells are capable of develop- fact that the amorfrutin molecules dock di- ing into any type of cell in the rectly onto a receptor in the cell nucleus body. However, they have such a called PPAR. This activates various genes degree of plasticity that they can that reduce the plasma concentration of also transform into cancer cells and certain fatty acids and glucose, which is a form tumors. The somatic stem sugar. The amorfrutins could possibly be cells generated with Brn4 pose a used as nutritional supplements or as mild lower risk of cancer, as they can remedies that are individually tailored to the patient. To find out for sure, the re- Dyed neuronal stem cells: The cell searchers will now have to test the effect of membranes are highlighted with red dye, and the cell nuclei with green and blue. the substances on diabetes patients. (PNAS, April 16, 2012, published online) Photo: Rolf Schulten – buchcover.com (top), MPI for Molecular Biomedicine (bottom)

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Climate Archive in Glass Sponge

11,000--old deep-sea sponge provides a record of previous environmental changes in the sea al Observatory of Japan (NAOJ) (bottom)

Climate researchers have discovered a new archive of histor- A glass sponge as the subject of a study: The photo on the left ical sea temperatures. Using the skeleton of a glass sponge shows a one-millimeter-wide cross section through the skeleton of vid Martinez-Delgado (MPIA). Small photo: R. Jay GaBany (Blackbird Observatory), Monorhaphis chuni. On the right, researcher Xiaohong Wang holds belonging to the Monorhaphis chuni species that lived in the the silicon dioxide skeleton, which measures more than two meters East China Sea for 11,000 years, an international team of re- long and is reminiscent of a glass fiber rod. searchers headed by scientists from the Max Planck Institute for Chemistry were able to show that the deep-sea tempera- the researchers concluded that the sea temperature in the ture changed several times in recent millennia. The skeleton, sponge’s environment increased at least once from just un- which is one centimeter thick and two meters long, resem- der two degrees Celsius to between six and ten degrees Cel- bles a glass fiber rod. The sponge, whose cells surrounded the sius. These changes in temperature were not previously glass rod during its lifetime, constantly formed new layers of known about and can be traced back to seamount eruptions. silicon dioxide. Based on isotopic and elemental analyses, (Chemical Geology, March 18, 2012)

Hungry Dwarf Galaxy

The little ones always grow up. This is that is just about to be swallowed up no less true of the universe: tiny galax- by NGC 4449. The researchers also stud- ies merge to become impressive gal- ied the shape of the distortion, ana- axy systems. But how do dwarf galax- lyzed the star types and searched for ies grow? In a similar way, it seems: structures that trace the orbit of the through cosmic cannibalism. Two galaxy that is about to be devoured. groups from the Max Planck Institute (Nature, February 9, 2012) for Astronomy discovered a mini-gal- axy that is currently “eating” another Cosmic meal: The NGC 4449 dwarf galaxy one. They found that a small compan- (top left) is in the process of devouring ion of the NGC 4449 dwarf galaxy in an even smaller galaxy (bottom right). The inset came from the 8.2-meter Subaru the Canes Venatici constellation is ac- telescope and resolves the smaller galaxy

tually an even smaller galaxy system into individual stars. Photos: Universitätsmedizin Mainz – Werner E.G. Müller (top, 2), R. Jay GaBany (Blackbird Observatory) in collaboration with Da Aaron Romanowsky (UCSC) and Jacob Arnold in collaboration with David Martinez-Delgado (MPIA) the National Astronomic

46 MaxPlanckResearch 2 | 12 Photo: MPI for Solid State Research – Sebastian Loth (top), MPI of Colloids and Interfaces – Kyu-Bock Lee (middle), fotolia (bottom) Max Planckscientistsareworking onit. Help inalittlebottle:Ananti-anxiety sprayisstillalongwayoff,but ( oftestsbeforeitcanbeusedonhumans. to undergoabattery structure forlearningandmemory. Thesubstancewillhave between neuronsinthehippocampus,animportantbrain Neuropeptide Sclearlyinfluencesthetransmissionofsignals iolytic effectofthesubstancewasachievedafterfourhours. utes afteradministrationthroughthenasalmucosa.Theanx- of thebrain.NeuropeptideSreachedbrainjust30min- ministered substancetospecialneuronsindifferentregions ceeded invisualizingthepathtakenbyintra-nasally ad- inMunich suc- from theMaxPlanckInstituteofPsychiatry the nasalmucosaanddeliveritseffectinbrain.Scientists iety substanceneuropeptideScanalsobeabsorbedthrough Planck researchers havenowdemonstratedthattheanti-anx- of theoriginalactivesubstanceislost.Usingmice,Max overcome theblood-brain barrier. Thiscanmeanthatalot Tablets thatareintendedtohaveaneffectinthebrainmust starfish, whoseskinisstuddedwith Ophiocoma wendtii Their workisinspiredbythebrittlestar crolenses fromcalciumcarbonate. ple, inexpensiveandtop-qualitymi- and Interfacesaremanufacturingsim- at theMaxPlanckInstituteofColloids simpleorganisms.Scientists from very Materials scientistscansometimeslearn Formed Naturally Microlenses – Nasal SprayforPanicAttacks through the nose brain the reach can substance Anxiety-reducing Neuropsychopharmacology, , arelativeofthe January 25, 2012, publishedonline) 25,2012, January the processingofopticalsignals,for lenses areoftechnologicalinterestin bon dioxideintheair. Suchmicro- cium-saturated solutionwiththecar- tal lensesformonthesurfaceofacal- surfactant –withwhichthetinycrys- one organicsubstance–inthiscasea Max Planckresearchers areusingjust such lenses.Likethebrittlestar, the technology. ple usingsemiconductor plex processes,forexam- com- lenses onlyinvery ufacture thesetypesof has beenpossibletoman- nications. Untilnow, it instance intelecommu- of high-qualityopticallenses. carbonate formanarray aligned hemispheresofcalcium calcium carbonate:Regularly Microscopic lensesmadefrom mu nications , March 6,2012) ( Nature Com- Unit intheWorld Smallest DataStorage arrangement. coloring illustratestheantiferromagnetic nitride base.Thealternatingblueandwhite data bitinjust12ironatomsonacopper IBM andtheMaxPlanckSocietystoreone An atomicstorageunit.Researchersfrom in currentstandardharddrives. can bepacked100timestighter than surface. Thismeansthatinformation were positionedonacoppernitride 12 ironatomsthat one databitinjust age ing thisinanextremelysmallstor- scientists havenowsucceededindo- zero andtheoneinadatabit.The two statesthatcouldstandforthe ble to ic field. don’t generateadisruptivemagnet- opposing directionsandtherefore arrange themselvesalternatelyin magnets, themagneticmoments distance betweenthem.Inantiferro- netic fieldandrequireaminimum direction. Theythusgenerateamag- nets, alignthemselvesinthesame can bevisualizedastinybarmag- netic momentsofallatoms,which age points.Insuchunits,themag- storage unitsuseferromagneticstor- age unit.Conventionalmagnetic oped anantiferromagneticdatastor- tron LaserScienceinHamburgdevel- Research attheCenterforFree-Elec- Max PlanckInstituteforSolidState nia, andaresearchgroupfromthe research divisioninSanJose,Califor- dustry. ScientistsworkinginIBM’s storage areopeninguptotheITin- New opportunitiesinmagneticdata ( Science point: theteamaccommodated generate, inacontrolledway, Prior tothis,itwasimpossi- , January13,2012) 2 | 12 MaxPlanckResearch MaxPlanckResearch SPECTRUM

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