Monthly Archive: March 2014

Idea: make a microcentrifuge using RC motors

The motors made for RC planes and cars are high speed and high power.

For example, the Turnigy Trackstar 1/10 12.0T 3300KV Brushless Motor, $23 specs are:
Kv: 3300
Max Voltage: 15v
Max current: 35amps
Watts: 550
Resistance: 0.0221Ohms
Max RPM: 50000

The load on a microfuge will be greater–22 tubes x 1.5 ml can be roughly 44g, figure a 100g total load with the rotor. So slower than max, but still quite fast.

High power ESC modules are sold to run these motors. So they take DC power, and a servo like signal (PWM), +5, GRD.

So a 10k RPM microfuge can be made with one of these motors + ESC, a servo for locking the lid, and a microcontroller to run it, take speed / time settings, and monitor and show the RPMs on a display.

Power could be from a PC power supply or a dedicated supply.

Links for March 2014

1 pixel moon
Guide to Convincing Parents to Vaccinate their Children
Zero senators per state
Why the Fed hates inflation
Progressive Caucus’s Better Off Budget
Levels of analysis of religion, Atran, Boyer & Wilson
Whistleblower Reveals Favoritism Toward the Rich, Robo-Signing at the IRS
Top 5 Bioinformatics papers
Measles spreading in the US
The Sober Truth: Debunking the Bad Science Behind 12-Step Programs and the Rehab Industry by Lance Dodes (Author), Zachary Dodes
Autism risk

New public health measures

Could new measures substantially improve public health?

What would be the effect if, say, 90% of the country wore filter masks for one week, and concentrated on washing hands?

Infection is a chain, one individual infects one or more others, and an infection gets passed on. That is how disease persists–for most infectious agents, not in one person for months on end, but passed serially every few months as an individual gets infected, and over a few weeks mounts an immune response and fights it off.

An infectious agent requires a basic reproduction factor, an R0, of more than one. If R0 > 1, an infection is growing more common, if R0 < 1, an infection is disappearing. For more diseases, for infection to persist it must spread.

Currently there are constant but weak efforts to reduce the spread of infection–encouraging the sick to stay home and hand washing. Vaccines for influenza. But what if a serious effort was made? A big effort could not be sustained, at least not in the US culture.

But what would be the effect of a large, short effort? If infection transmission can be stomped down for a short period, but long enough to break the chain of infection, it might have a large effect on public health. I wonder if this has been modeled?