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{455} is owned by tlh24 ehanson.
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ref: life-notes-2007 tags: electrode assay technology electrophysiology hack ad-hoc date: 01-03-2012 07:10 gmt revision:3 [2] [1] [0] [head]

properties of electrodes that are to penetrate the pia mater of a rhesus macaque:

  1. must easily go into a canned peach (in heavy or light sauce, it does not matter)
  2. does not go into pineapple cross-grain
  3. does go into the end-grain of pineapple
  4. penetrates the skin of a red grape (somewhat fresh) ~= pia
    1. The pia is a bit more tough than this, but is much less firm - if you are implanting electrodes that are any less than extremely sharp - e.g. etched - it will dimple the surface and not penetrate. Very sharp electrodes are key for getting through this tough membrane - which is even tougher in humans!
      • dimpling seems to silence cortical activity (observational evidence for this only)
      • however, once implanted lower-impedance electrodes work better. Low current microstimulation may be able to round the sharp tips of tungsten electrodes - we may want to test this.
    1. microdissection of the pia often damages the surface vasulature of the cortex, leading to localized infarctions, and hence should be avoided (unless you are really good)
    2. Bunching multiple elctrodes into one shaft - that is, making the shaft thicker and duller (albiet staggered) is not a good strategy for entering the brain (need to test the present monkeys).
  1. Cortical layer V (location of large pyramidal cells + betz cells in M1) in humans is 3-3.5mm below the surface, and ~1.6mm deep in rhesus. microwire/microwire arrays should have at least 2mm free wire length if intended for monkeys, and 4mm free wire if intended for humans.
    1. M1/S1 / central sulcus region is mostly inactive under isoflouro anesthesia, somewhat mangled/depressed with light ketamine, and silent with fentanyl. So, be careful with intraoperative recordings - the monkey/rat may be too deep, hence no cells to listen to!

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ref: bookmark-0 tags: language learning year french brain hack date: 09-03-2007 04:13 gmt revision:2 [1] [0] [head]

http://mirror.mricon.com/french/french.html -- "how i learned french in a year"

  • verbiste : verb conjugator for linux (Gnome)
  • When talking about software, it was FredBrooks in TheMythicalManMonth who said that people will always reinvent the wheel because it is intrinsically easier and more fun to write your own code than it is read someone else's code.

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ref: bookmark-0 tags: FPGA verilog VHDL hacking hardware prototype date: 04-09-2007 22:34 gmt revision:2 [1] [0] [head]

http://www.fpga4fun.com/

http://www.enterpoint.co.uk/

http://www.ixo.de/info/usb_jtag/ open source USB Jtag adapter, works with dragon (I think!)

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ref: notes-0 tags: matlab mysql hack date: 0-0-2006 0:0 revision:0 [head]

LD_PRELOAD=/lib/libgcc_s.so.1 matlab this allows you to command-line call mysql or other programs that use linux's standard libgcc.