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anything happening on this since 3 years?

yes it seems like. most of it seems however directed toward understanding this effect, and not toward applications. But i'm still convinced that we could find many very interesting applications !!! a few references from ADS: 1 2011PhRvA..83f3807B 1.000 06/2011 A E X R C U Brida, G.; Chekhova, M. V.; Fornaro, G. A.; Genovese, M.; Lopaeva, E. D.; Berchera, I. Ruo Systematic analysis of signal-to-noise ratio in bipartite ghost imaging with classical and quantum light 2 2011PhRvA..83e3808L 1.000 05/2011 A E R U Liu, Ying-Chuan; Kuang, Le-Man Theoretical scheme of thermal-light many-ghost imaging by Nth-order intensity correlation 3 2011PhRvA..83e1803D 1.000 05/2011 A E R C U Dixon, P. Ben; Howland, Gregory A.; Chan, Kam Wai Clifford; O'Sullivan-Hale, Colin; Rodenburg, Brandon; Hardy, Nicholas D.; Shapiro, Jeffrey H.; Simon, D. S.; Sergienko, A. V.; Boyd, R. W.; Howell, John C. Quantum ghost imaging through turbulence 4 2011SPIE.7961E.160O 1.000 03/2011 A E T Ohuchi, H.; Kondo, Y. Complete erasing of ghost images caused by deeply trapped electrons on computed radiography plates 5 2011ApPhL..98k1115M 1.000 03/2011 A E R U Meyers, Ronald E.; Deacon, Keith S.; Shih, Yanhua Turbulence-free ghost imaging 6 2011ApPhL..98k1102G 1.000 03/2011 A E R C U Gan, Shu; Zhang, Su-Heng; Zhao, Ting; Xiong, Jun; Zhang, Xiangdong; Wang, Kaige Cloaking of a phase object in ghost imaging 7 2011RScI...82b3110Y 1.000 02/2011 A E R U Yang, Hao; Zhao, Baosheng; Qiu

One of the authors of the STL (C++'s Standard Template Library) explains generic programming and slams Java.

"I'd rather not even *think* about developing a web application/webservice/web-whatever in standard C++... is it actually possible?? Perhaps with some weird Microsoft solutions... I bet your bank online services are written in Java. Certainly not in PHP+MySQL :)" Doing in C++ would be awesomely crazy, I agree :) But as I see it there are lots of huge websites that operate on PHP, see for instance Facebook. For the banks and the enterprise market, as a general rule I tend to take with a grain of salt whatever spin comes out from them; in the end behind every corporate IT decision there is a little smurf just trying to survive and have the back covered :) As they used to say in the old times, "No one ever got fired for buying IBM". "Industry has chosen Java not because of industrial-corporate marketing bullshit, but because of economics... it enables you develop robustly, reliably, error-prone, modular, well integrated etc... software. And the costs? Well, using java technologies you can set-up enterprise-quality web application servers, get a fully featured development environment (which is better than ANY C/C++/whatever development environment I've EVER seen) at the cost of exactly 0 (zero!) USD/GBP/EUR... Since many years now, the central issue in software development is not implementing algorithms, it's building applications. And that's where Java outperforms many other technologies." Apart from the IDE considerations (on which I cannot comment, since I'm not a IDE user myself), I do not see how Java beats the competition in this regard (again, Python and the huge software ecosystem surrounding it). My impression is that Java's success is mostly due to Sun pushing it like there is no tomorrow and bundling it with their hardware business.

OK, I think there is a bit of everything, wrong and right, but you have to acknowledge that Python is not always the simplest. For info, Facebook uses Java (if you upload picture for instance), and PHP is very limited. So definitely, in company, engineers like you and me select the language, it is not a marketing or political thing. And in the case of fb, they come up with the conclusion that PHP, and Java don't do everything but complement each other. As you say Python as many things around, but it might be too much for simple applications. Otherwise, I would seriously be interested by a study of how to implement a Python-like system on-board spacecrafts and what are the advantages over mixing C, Ada and Java.

"there is a call for a volunteer to develop the C++ coding standards" Go for it! :-)

Of course, the golden PaGMO coding standard! :)

New tool for interfacing C/C++ to MATLAB and Octave

Big news for developers out there: Google has just announced the release of a new, open sourced programming language called Go. The company ...

Having Google backing it will certainly help, even though they are presenting it as a "system level" (i.e., hard-core) language, and in that domain it is much more difficult to bullshit your way to a position of relevance. Look at Java: Sun pushed it like hell and it is certainly widely used in many contexts (corporate, web and embedded markets mostly), yet it completely failed to win the hearts of "open-source" developers (or, more generally, of those developers who are not forced to use it by virtue of some management-driven decision).

"or, more generally, of those developers who are not forced to use it by virtue of some management-driven decision" completely agree with that!!

"C++ is a horrible language. It's made more horrible by the fact that a lot of substandard programmers use it, to the point where it's much much easier to generate total and utter crap with it."

And the winner is... C++ :) Love the comment on Slashdot: "C++ Templates will turn the most pious programmer into a curse-slinging, chain-smoking alcoholic."

Nice one... However note the sample could be biased, because I'd expect some interaction between "using github" and "being a curse-slinging, chain-smoking alcoholic" ;-)

Fair enough :)

any thoughts?

I don't understand what kind of point the author is trying to make. Boost is not an STL implementation (and you can't actually use Boost if you don't have an underlying STL). So again, what's the conclusion?

The researchers used a global climate model to show that if an extreme emissions pathway -- RCP8.5 -- is followed up until 2035, allowing temperatures to rise 1°C above the 1970-1999 mean, and then SRM (Solar Radiation Management) is implemented for 25 years and suddenly stopped, global temperatures could increase by 4°C in the following decades.

Nice quantitative study. They treat the problem within the full uncertainty range of climate sensitivity parameter (much uncertain), very complete. However, at SRM ceasing, after an initial positive spike of Radiative Forcing, the rate of warming seems to return to rates predicted for the non-geoengineering case: "The 20-year temperature trends following SRM cessation are 0.2−0.6 °C/decade for the range of climate sensitivities (figure 5), comparable to those trends that occur under the RCP8.5 scenario without any SRM." I am actually working on a similar idea for deliberate Mars terraforming: aiming to cool the planet down before we introduce a positive Temperature raising feedback with greenhouse gases, maybe could be more efficient than warming itself.

By wearing clothes that have been dip-coated in a silver nanowire (AgNW) solution that is highly radiation-insulating, a person may stay so warm in the winter that they can greatly reduce or even eliminate their need for heating their home. With as extra bonus: Besides providing high levels of passive insulation, AgNW-coated clothing can also provide Joule heating if connected to an electricity source, such as a battery. The researchers demonstrated that as little as 0.9 V can safely raise clothing temperature to 38 °C, which is 1 °C higher than the human body temperature of 37 °C. How about that for personal comfort during the cold winter months

sounds almost like the asbestos story re-started :-)

Found an European project that takes care of the environmental, health and safety aspects of nanomaterials http://phys.org/news/2015-04-unleash-full-potential-nanomaterials.html

Theoretized 80 years ago was Breit-Wheeler pair production in which two photons result in an electron-positron pair (via a virtual electron). It is a relatively simple Feynmann diagram, but the problem is/was how to produce in practice a high energy photon-photon collider... The collider experiment that the scientists have proposed involves two key steps. First, the scientists would use an extremely powerful high-intensity laser to speed up electrons to just below the speed of light. They would then fire these electrons into a slab of gold to create a beam of photons a billion times more energetic than visible light. The next stage of the experiment involves a tiny gold can called a hohlraum (German for 'empty room'). Scientists would fire a high-energy laser at the inner surface of this gold can, to create a thermal radiation field, generating light similar to the light emitted by stars. They would then direct the photon beam from the first stage of the experiment through the centre of the can, causing the photons from the two sources to collide and form electrons and positrons. It would then be possible to detect the formation of the electrons and positrons when they exited the can. Now this is a good experiment... :)

True, but isnt it E2=(pc)^2 + (m0c^2)^2 such that for photons E\propto{pc} and for mass E\propto{mc^2}. I agree it will take a lot of energy, but this assumes that that wont be the problem at least. The question therefore is whether the mass flow of the photon rocket (fuel consumed to create photons, eg fission/fusion) is higher/lower than the mass flow for e-p creation. You are probably right that the low e-p cross-section will favour direct use of photons to create low thrust for long periods of time, but with significant power available the ISP might be higher for e-p pair creation.

In essence the equation tells you that for photons with zero rest mass m0 all the energy will be converted to momentum of the particles. If you want to accelerate e-p then you first spend part of the energy on creating them (~511 keV each) and you can only use the remaining energy to accelerate them. In this case the equation gives you a lower particle momentum which leads to lower thrust (even when assuming 100% acceleration efficiency). ISP is a tricky concept in this case because there are different definitions which clash in the relativistic context (due to the concept of mass flow). R. Tinder gets to a I_SP = c (speed of light) for a photon rocket (using the relativistic mass of the photons) which is the maximum possible relativistic I_SP: http://goo.gl/Zz5gyC .

Galactic Cosmic Radiation consisting of high-energy, high-charged (HZE) particles poses a significant threat to future astronauts in deep space. Aside from cancer, concerns have been raised about late degenerative risks, including effects on the brain. In this study we examined the effects of 56Fe particle irradiation in an APP/PS1 mouse model of Alzheimer's disease (AD). We demonstrated 6 months after exposure to 10 and 100 cGy 56Fe radiation at 1 GeV/µ, that APP/PS1 mice show decreased cognitive abilities measured by contextual fear conditioning and novel object recognition tests. Furthermore, in male mice we saw acceleration of Aβ plaque pathology using Congo red and 6E10 staining, which was further confirmed by ELISA measures of Aβ isoforms. Increases were not due to higher levels of amyloid precursor protein (APP) or increased cleavage as measured by levels of the β C-terminal fragment of APP. Additionally, we saw no change in microglial activation levels judging by CD68 and Iba-1 immunoreactivities in and around Aβ plaques or insulin degrading enzyme, which has been shown to degrade Aβ. However, immunohistochemical analysis of ICAM-1 showed evidence of endothelial activation after 100 cGy irradiation in male mice, suggesting possible alterations in Aβ trafficking through the blood brain barrier as a possible cause of plaque increase. Overall, our results show for the first time that HZE particle radiation can increase Aβ plaque pathology in an APP/PS1 mouse model of AD.

asm.js: it's really fast, backwards compatible, and now in the release version of Firefox. "By doing this the result is highly optimized and can be converted directly from this Asm.js syntax directly into ASSEMBLY without having to interpret it, as one would normally have to do with JavaScript" Here is great introduction to asm.js and C++ to js compilation: http://ejohn.org/blog/asmjs-javascript-compile-target

a bit of an overstatement. the trial is only at mice stage, but nevertheless interesting for its future application.

How you know you have been to long in xy. The Finnish version. My favorite is 33. You accept that 80°C in a sauna is chilly, but 20°C outside is freaking hot. Quite a lot of them are outdated, esp. about opening hours of shops, and one is definitely missing. Your normal mealtime has shifted to 11am for lunch and 5pm for dinner. But don't worry, it's a really comfy place here, isnt' it Jose??

... Finnish language has no future tense. That's true

everything expressed with "tomorrow I go to " or "in one year" etc? what about the distinction between to future events, one conditional on the other?

C-R-E-E-P-Y image in here...

Yeah, no doubt that's the entrance to hell... even more disturbing as it seems at least one house got in.

Yeah... I wonder if/how they plan to plug it?

Nice opinion piece by the creator of C++ Bjarne Stroustrup. Substitute "industry" with "science" and many considerations still apply :)

"for many, "programming" has become a strange combination of unprincipled hacking and invoking other people's libraries (with only the vaguest idea of what's going on). The notions of "maintenance" and "code quality" are typically forgotten or poorly understood. " ... seen so many of those students :( and ad "My suggestion is to define a structure of CS education based on a core plus specializations and application areas", I am not saying the austrian university system is good, but e.g. the CS degrees in Vienna are done like this, there is a core which is the same for everybody 4-5 semester, and then you specialise in e.g. software engineering or computational mgmt and so forth, and then after 2 semester you specialize again into one of I think 7 or 8 master degrees ... It does not make it easy for industry to hire people, as I have noticed, they sometimes really have no clue what the difference between Software Engineering is compared to Computational Intelligence, at least in HR :/

probably not practical for launchers nor for s/c but maybe for suborbital planes? nice idea anyway ...

Discover fundamentals of computer programming by playing a board game!