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Steve Jobs passed away. Reuters broke the news 7:56 EST with a post entitled "Apple co-founder Steve Jobs dead at 56". Steve’s advice for us was to live every day as if it was our last. Time is our most precious commodity. He used it well. The United States lost one of her finest innovators and a great human being.
by Walter Isaacson to be published later this month will be interesting.
The networks of nerve cells in our brain are often described as self-organizing. That is, intrinsic features of the nerve cells and the fashion in which the cells relate determine the shape the network. However, the mechanisms underlying the capacity of the neural population to shape itself are poorly understood. Better insight may be gained from the examination of other natural phenomena with self-organizing properties that emerge from complex interactions between the phenomenon and its environment. In meteorology, hurricanes and tornadoes constitute examples of self-organization.
While I was a postdoctoral fellow at the National Institutes of Health 15 years ago, I was privileged to witness the presentation of a team of Russian researchers who developed a method to image changes in temperature within 0.1° C on the surface of the brain through the skull. Local increases in temperature were associated with increases in cortical blood flow. Local cerebral blood flow, in turn, is related to nerve cell activity. The Russians sought to present a novel method to indirectly map cortical activity. Data obtained with this method was eventually reviewed years later in the journal Progress of Neurobiology.
In their presentation, the Russians showed temporal sequences of neural activation racing across cortex in a rat. The rat's whiskers on the face were stimulated. About one fifth of the rat's cortex processes sensory input from the whiskers. The animation showed bands of activation racing across the expanse of cortex nose-ward similar in appearance to tropical storms before the clouds coil around the center. This similarity sparked my interest in the development of tropical cyclones.
The hurricane season is about to begin. Reuters reported a week ago that an active Atlantic season is forecast. The National Hurricane Center (NHC) provides access to geographic information system (GIS) data that can be used as a starting point to examine the conditions conducive to self-organization. I am using Apple Macintosh computers for much of my work and compiled two software applications that may be useful in this process. One is a custom build of GRASS version 6.3 for Tiger. Version 7.0 for Leopard will be working before June 1. A demonstration of this application can be viewed at slideshare. The other application is a build of version 1.9 of degrib for Tiger. Version 1.91 for Leopard will be ready at the completion of GRASS 7.0. Instructions for the use of degrib can be found on the NHC web site. The applications run only on the Intel architecture. They are going to be available for download on my Sourceforge.net project site known as "Software for Small Budget Science". Join the effort!
Addenda
I work a lot with pictures professionally and have been using Apple computers for most of my career, except my Master's Thesis which I wrote on a DEC PDP 11. I was only a user. However, it always struck me with trepidation that I did not understand a thing of what was going on under the hood. I was eventually roped into computing, when the Apple operating system turned to UNIX around the year 2000. With the introduction of OS X, Apple had opened itself to Open Source computing which opened a new universe to me. Seven years later, I spent way more time with compiling packages than I ought to, and way more often than I liked, I ended up in a real fix. Regardless, the euphoria of empowerment outweighed the disappointment by far.
Today I report on one example of the kinds of adventure one may encounter on this road. Several months ago, I happened on the website of cups printing. Cups is the printing routine used in OS X. I found a pre-compiled binary of a more recent version than I had ready for installation. Since I wanted to be at the cutting edge, I downloaded the offering and installed it without reading the fine print. The result was that I could not print anymore. The fine print said that one had to re-install the operating system, if the update did not work. Oh!
I was not prepared to do that. So I compiled the most recent 1.4.x version for developers from source myself and installed it. After that, I could not even get passed the login window. I had a series of sweaty moments since then. I did not believe the functions that depend on cups! Much of OS X appears to depend on the cups library in one way or another. How can this be in the age decentralization? I managed to fix the problem by re-installing n older version in the single user mode.
Months later, I re-visited the cups website. The pre-compiled packages were gone, and it was recommended to try one the versions 1.3.x. After a number of tries, one of them worked and I offer the result on my SourceForge.net project (Software for Small Budget Science). The package is compiled with Tiger on Intel. It has worked well for me. Let my adventure be a warning.
