Both of the printers of mine that use the 28BYJ-48 steppers use them as unipolar steppers. When you write the firmware for the MCU of choice control the the printer (interpret the G-Code, read an SD-card, com with computer, and drive the printer) it is easy to assign the needed pins to drive unipolar steppers with ULN2803's or ULN2003's, as the current drivers. As such it makes no sense to use bipolar drivers when using the 28BYJ-48 stepper, it is much better to use ULN2803/ULN2003 drivers with an MCU that has at least the 16-GPIO's left over to run the 4 sets of steppers (X, Y, Z, E), so at least 20 GPIO's without a heated bed, and at least 23 GPIO's with a heated bed.
There have been attempts to link squalene to Gulf War Syndrome mainly due to the idea that squalene might have been present in an anthrax vaccine given to some military personnel during the 1991 Persian Gulf War. Studies found that deployed Persian Gulf War Syndrome patients are significantly more likely to have antibodies to squalene (95 percent) than asymptomatic Gulf War veterans (0 percent; p<.001).   The first of these published results concludes with the following statement: "It is important to note that our laboratory-based investigations do not establish that squalene was added as adjuvant to any vaccine used in military or other personnel who served in the Persian Gulf War era." The second publication, however, links the incidence of anti-squalene antibodies and Gulf War Syndrome to five specific lots of vaccine. Furthermore, they cite results of 1999 testing by the . Food and Drug Administration which found these specific lots of vaccine to contain squalene.  In response to these results, a committee of the US Institute of Medicine stated that "The committee does not regard this study as providing evidence that the investigators have successfully measured antibodies to squalene", since the authors did not perform the normal scientific controls needed to show that their test was specific to anti-squalene antibodies.  It has also been determined that the anthrax vaccines given to those US military personnel did not use squalene as an adjuvant.    The vaccines were also tested for squalene, and none was detected with standard methods.  Another method found no squalene in 37 of the 38 lots tested. One lot contained traces of squalene, at less than ten parts per billion, which is about one-thirtieth the level found in human blood.  The FDA stated that this trace of squalene probably came from a fingerprint, since the oils on human skin contain enough squalene to send these extremely sensitive tests "off the chart".