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The ionosphere extends from 30 miles to about 250 miles. As its name suggests, it contains ions -- charged particles. The ionosphere actually serves a practical purpose for those of us way down in the troposphere. Radio waves reflect off the ionosphere and bounce back to the surface, allowing us to hear radio transmissions from distances of hundreds and sometimes thousands of miles.


Figure 1-2: The aurora australis lights at the South Pole. These are the same type of lights found at the North Pole. (Photo courtesy of NOAA/Department of Commerce; http://www.photolib.noaa.gov; photo taken by Commander John Bortniak, NOAA Corps)


The northern lights, or aurora borealis, also occur in the ionosphere, usually between about 60 to 80 miles high. As solar radiation interacts with the upper atmosphere, nitrogen glows red and oxygen glows red or green. This is one of the few observable atmospheric phenomena to occur above the troposphere.

That completes our very quick tour of the atmosphere. In the next lesson we'll look at the recipe for weather, atmospheric pressure, and the Coriolis effect.


Assignment 1: What's Up? A Tour of the Atmosphere

The first assignment is easy. Next time you have a clear, starry night, go outside and look up at the stars. Remember that youre not just looking at the sky -- you're peering up from the very bottom of an ocean of air. The starlight youre seeing must pass through hundreds of miles of atmosphere before it reaches your eyes. Notice how the stars flicker and twinkle. What youre seeing is the atmosphere in action. Different portions of the atmosphere have different temperatures and densities and refract the incoming starlight.
Light bends as it passes through layers of air with different densities. You can see the same effect by putting a spoon in a glass of water; the spoon appears bent. Water has a different density from the air, and thats what creates the illusion. In the sky, the pinpoint light of the stars must pass through many such boundaries and changing air temperatures. That causes the light to refract or bend ever so slightly, causing a twinkle. (Planets are much closer and so appear larger than a zero-dimensional point. For that reason they dont flicker the way stars do.)
Okay, that was too easy, so Ill throw in some reading assignments too. Please read:

  • Tying Down the Wind, Chapter 6, Fresh Air.
  • Weather: How it Works and Why it Matters, pages 15 to 22.






Specialty: General medicine

Discipline: Pharmacology-1

Chair: Pharmacology, Pharmacognosy

Course II

Theme 6. Introduction to Autonomic Pharmacology. Cholinoceptor-Activating & Cholinesterase-Inhibiting Drugs.


Editor: assistant-professor, candidate of medical sciences ______ S.K.Seilkhanov



Semey 2008

Ratified at the meeting of the chair



the ___ of ______________________ 2009.


The Head of the chair_____________________M.N.Moussin


1. The theme: Introduction to Autonomic Pharmacology. Cholinoceptor-Activating & Cholinesterase-Inhibiting Drugs.

2. The aim: To know methods of pharmacologic interventions with autonomic drugs.

3. The objectives:

You should know:

1. General considerations of ANS

2. Neurotransmitters: synthesis, release and termination

3. Cholinoceptors: types and location

4. Adrenoceptors: types and location

5. Integration of Autonomic Function: local and system reflexes, complex organ control

6. Classification of cholinergic drugs

7. PK and PD of direct acting and indirect acting cholinomimetics

8. Comparison of some effects of choline esters

9. Comparison of some effects of cholinesterase inhibitors with different duration of action


You should be able to:

Describe the steps in the synthesis, storage, release, and termination of action of the major autonomic transmitters.

Name two cotransmitter substances.

Describe the organ system effects of stimulation of the parasympathetic and sympathetic systems.

Name examples of inhibitors of acetylcholine and norepinephrine synthesis, storage, and release. Predict the effects of these inhibitors on the function of the major organ systems.

List the determinants of blood pressure and describe the baroreceptor reflex response to blood loss and to administration of (1) a vasodilator, (2) a vasoconstrictor, (3) a cardiac stimulant, and (4) a cardiac depressant.

Name the major types of receptors found on autonomic effector tissues.

Describe the differences between the effects of surgical sympathetic ganglionectomy (interruption of ganglionic transmission by surgical removal of the sympathetic ganglia) and those of pharmacologic ganglion block.

Describe the actions of several toxins that affect nerve function: tetrodotoxin, saxitoxin, botulinum toxin, and latrotoxin.

List the locations and types of acetylcholine receptors in the major organ systems (CNS, autonomic ganglia, eye. heart, vessels, bronchi, gut, genitourinary tract, skeletal muscle, exocrine glands).

List the locations and types of acetylcholine receptors in the major organ systems (CNS, autonomic ganglia, eye. heart, vessels, bronchi, gut, genitourinary tract, skeletal muscle, exocrine glands).

Describe the effects of acetylcholine on the major organs. Relate the different pharmacokinetic properties of the various choline esters and cholinomimetic alkaloids to their chemical properties.

List the major clinical uses of cholinomimetic agonists. Describe the pharmacodynamic differences between direct- and indirect-acting cholinomimetic agents.

List the major signs and symptoms of (1) acute nicotine toxicity and (2) organophosphate insecticide poisoning.


Date: 2014-12-28; view: 781

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