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Be careful, the article is written by the company who did the migration to Ubuntu. Here is a comment by a police guy from IT (in french...). In brief he says that tyhe migration was not a problem for most of the people; exepc for some probleme with access. But it did cost money ! and the saving was not the main argument. "Personnellement concerné par la news qui n'en est pas une, je peux vous assurer que le message de Canonical est surtout commercial... Le choix d'Ubuntu est dû à son hégémonie et le fait que ce soit basé sur du Debian qui est considéré comme très stable. La distrib est d'une maintenance plus aisée que la plupart de celles qui ont été testées. "4500 postes" veut dire "4500 unités de gendarmerie" donc dans les brigades que vous connaissez... Pour ce qui est d'OpenOffice, le passage s'est fait assez tranquillement sauf pour les applis Access qui ont eu un peu de mal à passer sur le module Base...La plupart ont été reprise au sein d'applis php/mysql ou d'applis centralisées... Aujourd'hui, les gendarmes qui je le rappelle ne sont pas informaticiens mais vivent pour vous (au sens le plus strict je vous l'assure) utilisent donc firefox/thunderbird et oppenoffice en clients lourds, le reste étant des applis sur l'intranet ou "invisibles" pour l'utilisateur. Le passage à Ubuntu ne gène en rien dans l'utilisation car le trio précédemment cité est déjà connu et maîtrisé par nombre de mes collègues. Je ne suis pas censé m'exprimer en lieu et place de mes supérieurs mais à titre personnel, le choix d'Ubuntu est un choix intelligent car c'est une distribution avec une prise en main très accessible et avec une maintenance vraiment aisée pour les spécialistes informatiques dont je fais partie...Il ne faut pas oublier qu'une distribution plus élitiste aurait été maîtrisée par moins de monde et donc la maintenance aurait été plus coûteuse... Donc aujourd'hui nous "maîtrisons" cette part de notre infrastructure et la trans

Lotus Notes doesn't run on Linux anyway...

Here we go: we might not need liquid water after all on mars to get some nice flowering plants there! ... and terraform ? :-) Thirsty plants can extract water from the crystalline structure of gypsum, a rock-forming mineral found in soil on Earth and Mars.

Some plants grow on gypsum outcrops and remain active even during dry summer months, despite having shallow roots that cannot reach the water table. Sara Palacio of the Pyrenean Institute of Ecology in Jaca, Spain, and her colleagues compared the isotopic composition of sap from one such plant, called Helianthemum squamatum (pictured), with gypsum crystallization water and water found free in the soil. The team found that up to 90% of the plant's summer water supply came from gypsum.

The study has implications for the search for life in extreme environments on this planet and others.

Nature Commun 5, 4660 (2014)

Very interesting indeed. Attention is to be put on the form of calcium sulfate that is found on Mars. If it is hydrated (gypsum Ca(SO4)*2(H2O)) it works, but if it is dehydrated there is no water for the roots to take in. The Curiosity Rover tries to find out, but has uncertainty in recognising the hydrogen presence in the mineral: Copying : "(...) 3.2 Hydration state of calcium sulfates Calcium sulfates occur as a non-hydrated phase (anhydrite, CaSO4) or as one of two hydrated phases (bassanite, CaSO4.1/2H2O, which can contain a somewhat variable water content, and gypsum, CaSO4.2H2O). ChemCam identifies the presence of hydrogen at 656 nm, as already found in soils and dust [Meslin et al., 2013] and within fluvial conglomerates [Williams et al., 2013]. However, the quantification of H is strongly affected by matrix effects [Schröder et al., 2013], i.e. effects including major or even minor element chemistry, optical and mechanical properties, that can result in variations of emission lines unrelated to actual quantitative variations of the element in question in the sample. Due to these effects, discriminating between bassanite and gypsum is difficult. (...)"

forgot the reference http://www.msl-chemcam.com/doc/documents/577/Nachon%20et%20al%20Calcium%20sulfate%20veins%20characterized%20by%20ChemCam%20Curiosity%20at%20Gale%20Crater%20Mars_2013.pdf

The vibrissae of rats (et al) are examined and transferred to robotic devices for orientation and tactile exploration.

Abstract: In the last 3000 yr, one significant and rapid increase in the concentration of 14C in tree rings was observed; it corresponds to a gamma-ray energy input of 7x10^24 erg at Earth within up to one year in AD 774/5 (Miyake et al. 2012).

"Cast your name into deep space in style!"

Interesting approach, but with 99.9% probability they will miserably fail (at least in terms of their time schedule) simply because the technology is untested. I haven't read the refs (which miss by the way important works of E. Ahedo et al. on magnetic nozzle acceleration by ambipolar effects), but 1. using water means that you produce oxygen radicals which will erode chamber walls (ionisation efficiency is not 100% and experimental tests haven't been performed yet). 2. Electronic excitation (and radiation), rotational excitation, vibrational excitation, and dissociation are all processes which consume energy and reduce ionisation efficiency drastically. 3. It is a miniaturised Helicon thruster. Theoretical analysis probably does not consider near field effects. Far field models are probably not applicable due to the size of the thruster. I expect some surprises during thruster testing. In any case - good luck!

Apparently, there is only one qualification constraint regarding CubeSat propulsion which is related to volatile propellant. Since they use water as propellant and are also the owner of the CubeSat it is actually up to them how they qualify their thruster. Given that it is also possible to qualify the thruster within 18 months - since they define what "qualification" means.

Putting together the picture of how climate works. An informative slide that shows which are the climatic subsystems that can undergo(/have undergone in the past) bifurcations (Lenton et al., 2008 PNAS).

To follow up our discussio at breakfast

For all your statistics needs. The "Plastic Debris in the World's Oceans Report - UNEP" www.unep.org/regionalseas/marinelitter/.../docs/plastic_ocean_report.pdf‎ "Densities of plastic debris (Moore et al. 2001). Using nets to collect debris, the abundance of floating plastic averaged 334,271 pieces/km2" More worrying maybe is (http://www.ncbi.nlm.nih.gov/pubmed/22610295) "Our oceans eventually serve as a sink for these small plastic particles ("UV degraded surface plastic") and in one estimate, it is thought that 200,000 microplastics per km(2) of the ocean's surface commonly exist."

It's out there for TWO days and no one has posted it here yet? What's happening to the ACT... In any case, yet-another-year-ACT-didn't-make-it... Better luck next time.

read them when they came out - as probably 90% of ACTers but did not see any of them worth posting ...

I think e.g. de Tommaso et al. results have application in almost any business, ESA notwithstanding, in terms of implications for optimal office decor...

This guy solved a problem many people are trying to solve!!! The optimal control problem for the three body problem (restricted, circular) can be solved using continuation of the secondary gravity parameter and some clever adaptation of the boundary conditions!! His presentation was an eye opener ... making the work of many pretty useless now :)

I like when there are discussions evolving around entries

and on your problem with the RSS Tamas: its the same for me, you get the comments only for entries that you have posted or that you have commented on ...

quantumphysics holds ....

sleeping for 100 million years .... 

I will put it on my calendar...

Pretty nifty... we should look into this.

the cited paper by Baluška et al (http://dx.doi.org/10.1016/j.tree.2010.09.003) is a 2 page summary on the view that roots display swarm intelligence. Nothing really new compared to what those same authors have been writing about, but nice compilation of recent references on the subject.

Trolled :)

Navigation for robtos. That's how we should have done the hybrid controller study.

Well, it has always been a long discussion. Fungi are according to the most recent findings definitely no plants. Since they have always been in botanic textbooks, I would assume that they were never considered animals.No fauna, no flora, no stones. Maybe they are extraterrestrials. But that wouldn't solve the questions. Maybe they are just "fungi"?

what about then: "can we use them for space?"

Dario - perhaps worth giving a look to be up-to-date... There's even an article "Improving Classical and Decentralized Differential Evolution with New Mutation Operator and Population Topologies". They quote our CEC paper, but not the ParCo.

Isn't it a bit a paper-killing quote?

:) It's in the context of a review of the work that's been done about DE with island model in general, they don't evaluate. Pity they didn't refer to the ParCo article on topologies, as it was a bit more extensive and more focused on the method (as they do in the article) rather than on the problem (as was our CEC paper, if I recall well).

Of interest for Luzi, Pacome, Sante et al., I guess...

following the previous link