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Comment Eight is not enough (Score 1) 111

Never heard of the Chromatic scale? Schoenberg, Berg and others did.
All these scales do not divide the tones evenly in the frequency spectrum. They have to leave some out. Interestingly enough nor does the twelve note system, which does an even distribution in a logarithmic scale (base 12). At first hearing twelve tone music goes nowhere and slightly grates on you. After a while you start seeing (hearing) the purpose, but it is an acquired taste (no easy listening here). For an interesting read: The rest is noise, Alex Ross. That's minus the math

Comment Re:GPL? (Score 1) 128

From dmesg

[ 421.406145] netcat: module license 'unspecified' taints kernel.
[ 421.406149] Disabling lock debugging due to kernel taint
[ 421.416664] [netcat]: netcat - Cycles Per Instruction - Kernel Module Edition - 2014
[ 421.416668] [netcat]: netcat is Brandon Lucia, Andrew Olmstead, and David Balatero
[ 421.416670] [netcat]: On the web at
[ 421.416671] [netcat]: 'ogg123 -

So yes

Comment Re:This is about the stupidest thing for inventors (Score 1) 72

You are mistaken it is not disclosure. You just have proof that the document you produced, which only you can see, was certified to be generated on that day. It can be used if there is a dispute on prior knowledge. Let's say that you a Non disclosure agreement with someone and the topic is whatever you wanted to patent so they tell you what you wanted to patent. Then you have proof that you thought of this prior to the NDA. This could be important.

Comment Re:Hold up in court? (Score 1) 72

Not only that. It is also important for scientists and inventors.
It allows to time stamp ideas. I just did one with one of my articles in draft form. Yes it is not ready to release to the public but the idea is solid. So having a version of this notarized would be interesting to see how this affects patenting, without going through the terrible long process of submitting and waiting. Also junior scientists working in a lab can timestamp their contributions.

Comment Alternative path (Score 1) 413

RSX-11 (PDP11)->VAX/VMS -> UNIX-OS (VAX)-> OS400 (AS400) -> Xenix (PC) -> Linux (Slackware) -> Linux (Debian) -> Ubuntu

Yep, that old: 8 inch floppies and cupboard sized 10MByte Hard-disk. Interesting things came along, monitors, tree-based directory structures, GUI, a mouse, TCP/IP, the internet.

I have been known to use ms-dos, windows 3,95,98,2000,ME,XP, Vista, 7 but try to avoid it like the plague. Also played with Mac but thought it too clean, no idea what was happening behind the pretty pictures

Comment Re:Not so bad to have different systems. (Score 1) 2288

Actually the SI unit for dose is Gray (Gy) which is J/kg and expresses the amount of energy used to produce ionization and it was originally developed for Air which by strange coincindence is almost equivalent to mammal meat as far as the atomic content goes. The Sievert adds a factor to take into account the biological effect of different types of radiation. If in addition the sensitivity of the irradiated organ is taken into account it is still called Sievert and is a different number. I therefore do not consider Sievert to be an SI unit.

Hope this helps

Comment Re:The solution (Score 1) 171

No not a joke the only reason why you would get a "catastrophic" event is likely because the beam is focused and as such has a very high flux on a very small volume as dose = energy /mass then the mass of the irradiated part is very high. In order to get a lot of dose to the hand it is better to tune the energy down in such a way that the total energy gets deposited in the object you are interested in. Also note that also the density of the material is very important. Therefore a tungsten block would retain much more energy than a hand. I you can give me the number of particles/square cm I can calculate exactly what the dose is for the hand. This is what I do for a living. And yes I have treated patients with neutron beams, proton beams and photon beams, so I know what I am talking about. My point is that everyone seemed to be overawed by the sheer energy of the beam, while that is not the point it has to be the right energy.

As I explained in the first post the notion of high energy beams having low stopping power is counter intuitive as your reaction shows.

Hope this helps

Comment The solution (Score 1) 171

I was amazed at the ignorance displayed in this thread. In radiation therapy proton beams are used a lot to treat cancer so the problem is well known.
Of course you will need o know the fluence of the beam (e.g. number of particles/ square cm/ second) and the amount of time the hand has been in the beam.
Usually these beams are of relatively low flux, the particles in the beam do have a very high energy. The next thing you need to determine is
the amount of energy that will be transferred to the tissue. For this we use the notion of stopping power (i,e, energy deposited under the form of ionizing collisions per unit length). This quantity depends on the charge of the particle (squared) and the inverse of the speed of the particle (squared). This means, and most people find this counter intuitive, that the higher the energy, the lower the amount of energy being deposited. So in this case the deposited energy is very low, e.g. the beam passes almost right through the hand. I do not have any stopping power numbers for these type of energies handy but can only presume that they are very low. Some caveats, these line of thought only follows direct interactions and collisional interactions with electrons.
Most likely there is a larger component of nuclear interactions and ionizations coming from recoil events. Which will increase the dose.
In order to get the maximum effect with a proton beam one has to tune the beam in such a way that it comes to a complete halt inside the persons body
this is about 200MeV for a human, what is several orders of magnitude lower than the energies here at hand (pun unintended).

Anyway interesting question and at my next exam I will be sure to put it in. Now we will see if any of my students read slashdot ;-)


Comment Re:900mhz-1ghz Can Cause problems. (Score 1) 474

In follow up to my own submission.

Unfortunately all negative studies, that are well repeatable and do not show any increased permeability, Foiled again!
If there is a mechanism, this would not be it.

Record 1 of 5
de Gannes, FP; Billaudel, B; Taxile, M; Haro, E; Ruffie, G; Leveque, P; Veyret, B; Lagroye, I. 2009. Effects of Head-Only Exposure of Rats to GSM-900 on Blood-Brain Barrier Permeability and Neuronal Degeneration. RADIATION RESEARCH 172 (3): 359-367..
Author Full Name(s): de Gannes, Florence Poulletier; Billaudel, Bernard; Taxile, Murielle; Haro, Emmanuelle; Ruffie, Gilles; Leveque, Philippe; Veyret, Bernard; Lagroye, Isabelle
ISSN: 0033-7587
DOI: 10.1667/RR1578.1
Record 2 of 5
Finnie, JW; Blumbergs, PC; Cai, Z; Manavis, J. 2009. Expression of the water channel protein, aquaporin-4, in mouse brains exposed to mobile telephone radiofrequency fields. PATHOLOGY 41 (5): 473-475..
Author Full Name(s): Finnie, John W.; Blumbergs, Peter C.; Cai, Zhao; Manavis, Jim
ISSN: 0031-3025
DOI: 10.1080/00313020902885045
Record 3 of 5
Masuda, H; Ushiyama, A; Takahashi, M; Wang, JQ; Fujiwara, O; Hikage, T; Nojima, T; Fujita, K; Kudo, M; Ohkubo, C. 2009. Effects of 915 MHz Electromagnetic-Field Radiation in TEM Cell on the Blood-Brain Barrier and Neurons in the Rat Brain. RADIATION RESEARCH 172 (1): 66-73..
Author Full Name(s): Masuda, Hiroshi; Ushiyama, Akira; Takahashi, Miyuki; Wang, Jianqing; Fujiwara, Osamu; Hikage, Takashi; Nojima, Toshio; Fujita, Koji; Kudo, Motoshige; Ohkubo, Chiyoji
ISSN: 0033-7587
DOI: 10.1667/RR1542.1
Record 4 of 5
Masuda, H; Ushiyama, A; Hirota, S; Wake, K; Watanabe, S; Yamanaka, Y; Taki, M; Ohkubo, C. 2007. Effects of subchronic exposure to a 1439 MHz electromagnetic field on the microcirculatory parameters in rat brain. IN VIVO 21 (4): 563-570..
Author Full Name(s): Masuda, Hiroshi; Ushiyama, Akira; Hirota, Shogo; Wake, Kanako; Watanabe, Soichi; Yamanaka, Yukio; Taki, Masao; Ohkubo, Chiyoji
ISSN: 0258-851X
Record 5 of 5
Franke, H; Streckert, J; Bitz, A; Goeke, J; Hansen, V; Ringelstein, EB; Nattkamper, H; Galla, HJ; Stogbauer, F. 2005. Effects of universal mobile telecommunications system (UMTS) electromagnetic fields on the blood-brain barrier in vitro. RADIATION RESEARCH 164 (3): 258-269..
ISSN: 0033-7587

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In less than a century, computers will be making substantial progress on ... the overriding problem of war and peace. -- James Slagle