Diabetes and Blood Sugar

Blood glucose.

It’s something I have to worry about, as does every diabetic. Too much glucose in the blood, and the circulatory system is affected. This in turn can lead to problems with eyes, kidneys, feet, and the entire nervous system, not to mention cardiovascular problems. Diabetes is one of the leading causes of blindness, kidney failure, foot and leg amputations, heart attacks, stroke—in short, high blood sugar can kill you. Not rapidly, but the long tem effects of uncontrolled high blood sugar (hyperglycemia) are all too often lethal.

If your body starts breaking down fats and proteins for energy, which can happen if insulin levels in your blood drop too low, death can come in a few days, from ketoacidosis.

Low blood sugar can be just as much of a problem, and can kill you much faster. Your brain runs on glucose, so low blood sugar (hypoglycemia) affects the brain. It can kill you much faster than high blood sugar. Generally you can feel it coming on, but this awareness tends to fade with time—a condition called hypoglycemia unawareness.

A lot of people with diabetes wind up in emergency rooms because they simply pass out from low blood sugar, without warning. Some never wake up.

If you don’t have diabetes, you don’t have to think about this. When your blood sugar rises, your pancreas pumps out a hormone called insulin, which helps the cells of your body to use glucose, either for energy or in storage as fat. When it falls, your liver releases stored glucose to the blood. As a result, your blood sugar fluctuates only slightly, and you don’t really have to think about it.

For those of us with type 1 diabetes, the pancreas no longer manufactures insulin. For some of us, the liver no longer dumps glucose into our system when needed, either. Since we have to inject insulin (or have a pump deliver it) too much insulin, too little food, too much exercise or some unknown effect can make our blood sugar plummet. The treatment is sugar. Straight glucose is fastest, but any carbohydrate will do.

In Homecoming, the R’il’nai and R’il’noids have a similar problem. Esper work means using the brain—hard—and the brain runs on glucose. The liver can only dump a limited amount of sugar into the blood, and then it runs out of stored glucose. Too much esper work without readily available carbohydrates can cause low blood sugar, which they call “esper shock.”

When Roi is leaning to use his esper talents, one of the first things he has to learn is that he must eat while he is using those abilities, whether or not he feels hungry. How he feels in esper shock is based very much on my own experience and that of others with diabetes.

When I was first diagnosed, I had a number of symptoms—sweating, shaking, lips tingling. Others may get very aggressive, fight someone who is trying to get them to eat, or just not act like themselves. Still others quietly pass out. Right now, my most reliable symptom is a kind of flare in my visual field that blurs my vision, along with a feeling of weakness. I’d still have some real problems without a blood glucose meter (which requires a blood sample) and a continuous glucose monitor. I still wonder at how I got through the first years, before meters, let alone continuous monitors, were available

Now if they’d just make the alarm on the CGM loud enough to wake me up at night ….

Momentum and Teleportation

Teleportation in Homecoming requires that energy, momentum, angular momentum and mass be conserved—all basic laws of physics. We’ll skip mass and angular momentum for right now, and just look at the situation where something is moving in a straight line.

Anything that is moving has both kinetic energy (energy of motion) and momentum, but the two are not the same. The difference is usually expressed mathematically: energy is half the mass times the square of the velocity and momentum is the mass times the vector velocity, but for many that just makes if more confusing. Let’s try this, instead. (If you don’t understand mass, think weight.)

Consider a car. Let it be a big, heavy car, say an SUV. Suppose it is coasting at a steady speed, say, 30 miles an hour to the west. Can a mosquito stop it by hitting the windshield? Not likely! The car’s resistance to having its steady motion changed is due to its momentum. This momentum has a direction—the direction the car is moving. Friction will slow it down, eventually, by transferring its momentum to the earth, but for the moment we’ll ignore that.

It also has kinetic energy. If the speed is doubled, the momentum will also double—but the kinetic energy will increase by a factor of four.

Remember momentum has a direction. Suppose we have another SUV moving 30 miles an hour to the east. Speed to the east and speed to the west cancel, so the momentum of the two-car system is zero. Their kinetic energy does not cancel, as can be seen if the two cars meet head-on—when the dust settles, they will be stationary at the point where they met. But the energy will have gone into crumpling metal (and whatever else makes up the cars) and ultimately into heat.

It is possible for two objects to bounce off of each other in such a way that energy, as well as momentum, is conserved. But if the momentum adds up to zero before the impact, it must also add up to zero after the impact. This is a common problem in billiards, though in this case the balls are most often moving at angles to each other so the vector sum of the momentum is not zero—but it will still be the same after the collision as it was before.

The conservation of momentum, in fact, nicely encapsulates Newton’s laws of motion.

Now consider Roi’s problem in teleporting to a very different location. He is moving with the planet under his feet. For illustration, let’s assume he is on the equator, at sea level, at sunrise, and wants to go to the opposite hemisphere, also on the equator at sea level, but at sunset.

Assuming he is on a planet like the Earth, he is moving toward the sun at around a thousand miles an hour, and the area he wants to teleport to is moving away from the sun at the same speed. No change in kinetic energy, but if he doesn’t do something about momentum, he’ll arrive moving about two thousand miles an hour relative to his surroundings—not a very survivable teleport!

My solution is strictly science fiction—I assume it is possible for a person (or a machine) to transfer or “swap” momentum from one mass to another. But they’d better remember to do it!

Follow-me (Homecoming Glossary)

FOLLOW-ME: #scifi A person teleporting himself normally brings along anything he is touching (such as clothing) unless deliberately leaving it behind. (A person could, for instance, teleport into or out of an isolation suit.) For massive objects, a “follow-me” circuit will link the object to a small receiver carried by the teleporter, as well as providing the extra energy needed for the teleport of the object.

Screamer (Homecoming Glossary)

SCREAMER: #scifi An electronic gadget that produces a burst of telepathic noise. They can be set for various intensities, and a good telepath can to a certain extent work through one, but not easily or without special training.

Tack-healing (Homecoming Glossary)

TACK-HEALING: #scifi In Healing broken bones, the growth of calcification tends to be much slower than aligning the bone fragments and forcing rapid growth of cartilage. The most common way of Healing such injuries is to use Healing to align bone fragments  and accelerate cartilage growth, known as tack-healing because the bone, while “mended,” has only a fraction of normal strength. The patient is then instructed to avoid putting excessive stress on the damaged bone while calcification is occurring.

Anchor (Homecoming Glossary)

ANCHOR: #scifi Long-distance teleportation requires a very precise set of coordinates and a great deal of work if one is going to a new location, and the range covered is limited. If a fellow telepath is located near the point aimed for, it is possible to arrange a “two-ended” teleport which greatly reduces the energy needed. The telepath at the destination is referred to as an anchor, and the process is called anchoring.

Teleportation (Homecoming Glossary)

TELEPORTATION, ESPER: #scifi Traveling or moving an object between two points without going through intermediate points using mind power alone or boosted by a mental link to an external source of power.

Esper Link (Homecoming Glossary)

ESPER LINK: A mind-link between two telepaths, generally used of an ongoing link.

Latent Telepath (Homecoming Glossary)

LATENT (ESPER): #scifi An individual who caries enough of the R’il’nian genes associated with esper abilities to have some ability at telepathic communication. Generally latents find it difficult to contact each other, but communicate relatively easily with a full telepath, and have above average shielding ability.

Xenotelepathy (Homecoming Glossary)

XENOTELEPATHY: Telepathic communication with a member of a non-human intelligent species.