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The universe bounces back, & robots fight humans: Today on New Scientist: stories from 13 October 2010

Strive as we might to make sense of the world, some mysteries still confound us. Here are 13 of the most perplexing - cracking any one of them could yield profound truths

"Die Universitäten von heute haben ein Problem: Ihnen gehen die Mythen verloren. Als die Alchemisten früher ihre Säfte zusammenmischten, konnte es knallen oder Gold regnen. Darwin und Humboldt erkundeten eine Welt, in der es überall vor allem zwei Dinge gab: Abenteuer und Gefahr. Heute gibt es keine Kontinente mehr zu entdecken, kein Gold zu destillieren. ZEIT Campus 2/13 Dieser Text stammt aus dem aktuellen ZEIT Campus Magazin, das am Kiosk erhältlich ist. Klicken Sie auf das Bild, um auf die Seite des Magazins zu gelangen. Dieser Text stammt aus dem aktuellen ZEIT Campus Magazin, das am Kiosk erhältlich ist. Klicken Sie auf das Bild, um auf die Seite des Magazins zu gelangen. Geblieben ist theoretischer Wettstreit: Wer entwickelt eine noch abgefahrenere Theorie? Ein noch besseres Modell? Das ist nicht nichts. Aber etwas fehlt. Bei unserer Arbeit vollbringen wir keine Wunder, keine Narben zeugen von Heldenmut.Vielleicht gibt es deshalb so viele neurotische Profs: Sie müssen den Verlust des Abenteuers in ihrem Forscherleben kompensieren"

"Die Ergebnisse zeigen, dass das angeborene Fluchtverhalten auf Kohlendioxid in Fruchtfliegen je nach ihrem Sättigungszustand von zwei parallelen neuronalen Schaltkreisen gesteuert wird. „Ist die Fliege hungrig, verlässt sie sich nicht mehr auf die "direkte Leitung", sondern benutzt Hirnzentren, mit denen sie interne und äußere Signale abwägen und eine ausgewogene Entscheidung treffen kann", erklärt Grunwald-Kadow und fügt hinzu: „Es ist faszinierend, in welchem Ausmaß der Stoffwechsel und Hunger die verarbeitenden Prozesse im Gehirn beeinflussen." ***** Lasse B. Bräcker, K.P. Siju, Nelia Varela, Yoshinori Aso, Mo Zhang, Irina Hein, Maria Luisa Vasconcelos, Ilona C. Grunwald Kadow Essential role of the mushroom body in context dependent CO2 avoidance in Drosophila Current Biology, 13 June 2013 Max-Planck-Institut für Neurobiologie"

The Google Science Fair is an online science competition seeking curious minds from the four corners of the globe. Anybody and everybody between 13 and 18 can enter. All you need is an idea.

Susanna Larsson: Kaffeetrinkerinnen haben ein geringeres Risiko für Hirninfarkte http://www.wissenschaft.de/wissenschaft/news/313141.html (Jingmei Li, Karolinska Institutet, et al.: Breast Cancer Research, Bd. 13, Artikel R49) Yvonne T. van der Schouw (UMC Utrecht) et al.: Arteriosclerosis, Thrombosis, and Vascular Biology: Journal of the American Heart Association, doi: 10.1161/ATVBAHA.109.201939 http://www.wissenschaft.de/wissenschaft/news/311350.html Helena Jernström: Kaffee senkt das Brustkrebsrisiko http://www.wissenschaft.de/wissenschaft/gutzuwissen/291553.html

Astronomers' new observations have spotted the most distant galaxy ever seen. The galaxy's light comes from about 13.1 billion light-years away, making it one of the first galaxies to form after the Big Bang.

Using entire galaxies as lenses to look at other galaxies, researchers have a newly precise way to measure the size and age of the universe and how rapidly it is expanding, on a par with other techniques. The measurement determines a value for the Hubble constant, which indicates the size of the universe, and confirms the age of the universe as 13.75 billion years old, within 170 million years. The results also confirm the strength of dark energy, responsible for accelerating the expansion of the universe.

ScienceDaily (Jan. 13, 2011) - It is becoming well accepted that, as well as too little exercise, too much sitting is bad for people's health. Now a new study has found that it is not just the length of time people spend sitting down that can make a difference, but also the number of breaks that they take while sitting at their desk or on their sofa. Plenty of breaks, even if they are as little as one minute, seem to be good for people's hearts and their waistlines.

COULD the structure of space and time be sketched out inside a cousin of plain old pencil lead? The atomic grid of graphene may mimic a lattice underlying reality, two physicists have claimed, an idea that could explain the curious spin of the electron. Graphene is an atom-thick layer of carbon in a hexagonal formation. Depending on its position in this grid, an electron can adopt either of two quantum states - a property called pseudospin which is mathematically akin to the intrinsic spin of an electron. Most physicists do not think it is true spin, but Chris Regan at the University of California, Los Angeles, disagrees. He cites work with carbon nanotubes (rolled up sheets of graphene) in the late 1990s, in which electrons were found to be reluctant to bounce back off these obstacles. Regan and his colleague Matthew Mecklenburg say this can be explained if a tricky change in spin is required to reverse direction. Their quantum model of graphene backs that up. The spin arises from the way electrons hop between atoms in graphene's lattice, says Regan. So how about the electron's intrinsic spin? It cannot be a rotation in the ordinary sense, as electrons are point particles with no radius and no innards. Instead, like pseudospin, it might come from a lattice pattern in space-time itself, says Regan. This echoes some attempts to unify quantum mechanics with gravity in which space-time is built out of tiny pieces or fundamental networks (Physical Review Letters, vol 106, p 116803). Sergei Sharapov of the National Academy of Sciences of Ukraine in Kiev says that the work provides an interesting angle on how electrons and other particles acquire spin, but he is doubtful how far the analogy can be pushed. Regan admits that moving from the flatland world of graphene to higher-dimensional space is tricky. "It will be interesting to see if there are other lattices that give emergent spin," he says.

ScienceDaily (May 13, 2011) - Parents know the unparalleled joy and wonder of hearing a beloved child's first words turn quickly into whole sentences and then babbling paragraphs. But how human children acquire language-which is so complex and has so many variations-remains largely a mystery. Fifty years ago, linguist and philosopher Noam Chomsky proposed an answer: Humans are able to learn language so quickly because some knowledge of grammar is hardwired into our brains. In other words, we know some of the most fundamental things about human language unconsciously at birth, without ever being taught.

ScienceDaily (Apr. 13, 2011) - If mice commuted, their brains might find it progressively harder to navigate the maze of Los Angeles freeways. A new study reveals that after short-term exposure to vehicle pollution, mice showed significant brain damage -- including signs associated with memory loss and Alzheimer's disease.

Common beans (Phaseolus vulgaris L.) are the most important legume staple food in Kenya coming second to maize. In Central Highlands of Kenya, the 0.4-0.5ton ha-1 output is below the genetic yield potential of 1.5-2ton ha-1 partly due pests and diseases. Plant parasitic nematodes (PPN) have been reported to cause yield losses of up to 60% on beans. Though bean production is important in the Central highlands of Kenya, information on PPN associated with the beans in the region is lacking. This study was therefore undertaken to establish the diversity of PPN associated with common beans and to assess the root knot nematode damage on beans in the region. The study covered 50 farms (32 in Kirinyaga and 18 in Embu Counties) distributed in eight localities namely Kibirigwi (L1), Makutano (L2), Kagio (L3), Mwea (L4) and Kutus (L5) in Kirinyaga County and Nembure (L6), Manyatta (L7) and Runyenjes (L8) in Embu County and covering three Agro Ecological Zones (AEZs); UM2 (L1, L2, L3 & L4), UM3 (L5, L7 & L8) and UM4 (L6) AEZs. Manyatta (L7) and Nembure (L6), had the highest and second highest gall indices, respectively, while Kibirigwi (L1), Makutano (L2) and Mwea (L4) had some of the lowest gall indices. The most common PPN in bean roots were Meloidogyne spp. Pratylenchus spp. and Scutellonema spp. with a frequency of 94.38%, 78.25% and 59.13%, respectively. This further confirm the importance of these nematodes in bean production systems. Upper Midland 3 (UM3) AEZs and UM4 had higher nematode population densities and diversity than UM2. Disease severity and nematode composition and distribution were notably low in the irrigated areas Kibirigwi, Kagio and Mwea compared to rain-fed areas such as Makutano, Nembure and Manyatta.

The contamination and potential ecological risk posed by heavy metals from thirteen (13) sediment samples from different sampling sites along the lower portion of Agusan River were analyzed and assessed using different pollution indices. The results obtained shows that the total digest concentrations of different heavy metals under investigation have the following order: Cd < Pb < Zn < Mn, for both first sampling periods. The speciation and distribution pattern have shown that significant amounts of all metals are present in the residual fraction. Similarly, oxide-bound and organic-bound fractions were found to be highly important for Zn and Mn while Cd and Pb were significantly associated in the residual and exchangeable fractions. The results of different pollution indices moreover, showed that among all the heavy metals being studied, Cd posed the highest environmental risk across all sampling stations in both sampling periods and Mn metal was highly enriched and abundant in all of the sampling stations. Importantly, PCA results suggest that Zn, Mn and Pb may have the same origin while Cd might be coming from different sources, and this is corroborated well with the cluster analysis results. The results obtained from this work provide baseline data on the assessment of heavy metal pollution in the lower portion of Agusan River. Importantly, the acquired environmental indices will certainly help safety managers in assessing and interpreting the potential risk of the sediment associated chemical status that might adversely affect aquatic organisms in the selected sampling sites.

"The 18th-century philosopher David Hume (much quoted by Mr. Lehrer) didn't have an M.R.I. scanner at his disposal, but he framed the question in much the same way. His major work, "A Treatise of Human Nature," explored the ways in which habit, or "custom," rules our lives. Hume's experiments with perception - how we respond to colors, distance, numerical sets - prefigure the rigorous science of Professor Kahneman. His intent was to show us "the natural infirmity and unsteadiness both of our imagination and senses." Consciousness, like philosophy itself, stands on a "weak foundation.""

"Suffering for Fashion … and Sex Appeal? Nine out of ten women wear shoes that are too tight for them. And eight out of ten women admit to wearing shoes that hurt... These ideas have been explored previously by numerous other researchers. For example, Rossi notes that high-heels alter the tilt of the pelvis, resulting in more prominence of the buttocks and displaying of the breasts, creating a "come-hither pose" also described by Rossi as the "pouter pigeon" pose, "with lots of breast and tail balanced precariously on a pair of stilts " http://ed.iiQii.de/gallery/Querdenkerinnen/High_Heel_Pumps_wikipedia_org

"Craig Venter: 'This isn't a fantasy look at the future. We are doing the future' The pioneering American scientist, who created the world's first synthetic life, is building a gadget that could teletransport medicine and vaccines into our homes or to colonists in space"

The psychology of vengeance explains much about the state of the world and suggests the war on terror can never succeed, says Metin Basoglu